:: Formalization of the Advanced Encryption Standard -- Part {I} :: by Kenichi Arai and Hiroyuki Okazaki environ vocabularies AESCIP_1, DESCIP_1, TARSKI, XBOOLE_0, FINSEQ_1, RELAT_1, FUNCT_1, ARYTM_1, FUNCT_2, FINSEQ_2, NAT_1, MARGREL1, ZFMISC_1, SUBSET_1, NUMBERS, INT_1, CARD_1, JORDAN3, XXREAL_0, ARYTM_3, ORDINAL4, FINSEQ_5, XCMPLX_0; notations TARSKI, XBOOLE_0, ZFMISC_1, SUBSET_1, RELAT_1, FUNCT_1, ORDINAL1, RELSET_1, PARTFUN1, FUNCT_2, BINOP_1, CARD_1, NUMBERS, XCMPLX_0, XXREAL_0, NAT_1, INT_1, NAT_D, FINSEQ_1, FINSEQ_2, MARGREL1, FINSEQ_4, FINSEQ_6, DESCIP_1; constructors RELSET_1, FINSEQ_4, NAT_D, FINSEQ_6, DESCIP_1, BINOP_1; registrations FINSEQ_1, RELSET_1, FINSEQ_2, FUNCT_2, ORDINAL1, MARGREL1, INT_1, NAT_1, XXREAL_0, XBOOLE_0, FUNCT_1, XREAL_0, FINSEQ_4; requirements BOOLE, SUBSET, NUMERALS, ARITHM, REAL; equalities FINSEQ_1, FINSEQ_2; theorems TARSKI, FUNCT_1, FUNCT_2, XXREAL_0, XREAL_1, FINSEQ_6, XREAL_0, NAT_1, INT_1, FINSEQ_1, CARD_1, BINOP_1, NAT_D, FINSEQ_2, FINSEQ_4, RFINSEQ, FINSEQ_5, XBOOLE_0, ORDINAL1, DESCIP_1, MARGREL1, NAT_2, WSIERP_1, XCMPLX_1, FINSEQ_3; schemes FUNCT_2, FINSEQ_1, NAT_1, BINOP_1, RECDEF_1; begin :: Preliminaries theorem XLMOD02: for k,m be Nat st m <> 0 & (k+1) mod m <> 0 holds (k+1) mod m = (k mod m)+1 proof let k,m be Nat; assume C1: m <> 0 & (k+1) mod m <> 0; (k mod m)+1 <= m by NAT_D:1,C1,NAT_1:13; then P1: (k mod m)+1-1 <= m-1 by XREAL_1:9; P2: (k+1) mod m = ((k mod m)+1) mod m by NAT_D:22; k mod m < m-1 proof assume not k mod m < m-1; then (k+1) mod m = (m-1+1) mod m by XXREAL_0:1,P1,P2 .= 0 by INT_1:50; hence contradiction by C1; end; then (k mod m)+1 < m-1+1 by XREAL_1:8; hence (k+1) mod m = (k mod m)+1 by NAT_D:24,P2; end; theorem XLMOD01: for k,m be Nat st m <> 0 & (k+1) mod m <> 0 holds (k+1) div m = k div m proof let k,m be Nat; assume C1: m <> 0 & (k+1) mod m <> 0; k+1 = ((k+1) div m )*m+((k+1) mod m) by INT_1:59,C1 .= ((k+1) div m )*m+((k mod m)+1) by XLMOD02,C1; then P1: ((k+1) div m)*m+(k mod m)-(k mod m) = (k div m )*m+(k mod m)-(k mod m) by INT_1:59,C1; thus ((k+1) div m) = (k div m)*m / m by XCMPLX_1:89,C1,P1 .= (k div m) by XCMPLX_1:89,C1; end; theorem XLMOD02X: for k,m be Nat st m <> 0 & (k+1) mod m = 0 holds m-1 = (k mod m) proof let k,m be Nat; assume C1: m <> 0 & (k+1) mod m = 0; then (k mod m)+1 <= m by NAT_D:1,NAT_1:13; then P1: (k mod m)+1-1 <= m-1 by XREAL_1:9; P2: (k+1) mod m = ((k mod m)+1) mod m by NAT_D:22; assume not k mod m = m-1; then k mod m < m-1 by XXREAL_0:1,P1; then k mod m+1 < m-1+1 by XREAL_1:8; hence contradiction by P2,NAT_D:24,C1; end; theorem XLMOD01X: for k,m be Nat st m <> 0 & (k+1) mod m = 0 holds (k+1) div m = (k div m)+1 proof let k,m be Nat; assume C1: m <> 0 & (k+1) mod m = 0; then P3: k mod m = m-1 by XLMOD02X; P4: k+1 = ((k+1) div m)*m+((k+1) mod m) by INT_1:59,C1 .= ((k+1) div m)*m by C1; P5: k = (k div m )*m+(k mod m) by INT_1:59,C1 .= (k div m)*m+m-1 by P3; thus ((k+1) div m) = ((k div m)+1)*m / m by XCMPLX_1:89,C1,P4,P5 .= ((k div m)+1) by XCMPLX_1:89,C1; end; theorem XLMOD03: for k,m be Nat holds (k-m) mod m = k mod m proof let k,m be Nat; thus (k-m) mod m = (k+m*(-1)) mod m .= k mod m by NAT_D:61; end; theorem XLMOD04: for k,m be Nat st m <> 0 holds (k-m) div m = (k div m)-1 proof let k,m be Nat; assume AS: m <> 0; thus (k-m) div m = (k+m*(-1)) div m .= (k div m)+-1 by AS,NAT_D:61 .= (k div m)-1; end; definition let m,n be Nat, X,D be non empty set; let F be Function of X, m-tuples_on(n-tuples_on D); let x be Element of X; redefine func F.x -> Element of m-tuples_on(n-tuples_on D); coherence proof F.x in m-tuples_on(n-tuples_on D); hence thesis; end; end; definition let m be Nat, X,Y,D be non empty set; let F be Function of [:X,Y:], m-tuples_on D; let x be Element of X,y be Element of Y; redefine func F.(x,y) -> Element of m-tuples_on D; coherence proof F.(x,y) in m-tuples_on D; hence thesis; end; end; theorem LM01: for m,n be Nat, D be non empty set, F1,F2 be Element of m-tuples_on (n-tuples_on D) st for i,j be Nat st i in Seg m & j in Seg n holds (F1.i).j = (F2.i).j holds F1 = F2 proof let m,n be Nat, D be non empty set, F1,F2 be Element of m-tuples_on (n-tuples_on D); assume AS: for i,j be Nat st i in Seg m & j in Seg n holds (F1.i).j = (F2.i).j; F1 in m-tuples_on (n-tuples_on D); then P1: ex s be Element of (n-tuples_on D)* st F1 = s & len s = m; F2 in m-tuples_on (n-tuples_on D); then P2: ex s be Element of (n-tuples_on D)* st F2 = s & len s = m; now let i be Nat; assume 1 <= i & i <= len F1; then P4: i in Seg m by P1; then i in dom F1 by FINSEQ_1:def 3,P1; then F1.i in rng F1 by FUNCT_1:3; then F1.i in n-tuples_on D; then P6: ex s be Element of D* st F1.i = s & len s = n; then reconsider F1i = F1.i as Element of D*; i in dom F2 by FINSEQ_1:def 3,P2,P4; then F2.i in rng F2 by FUNCT_1:3; then F2.i in n-tuples_on D; then R6: ex s be Element of D* st F2.i = s & len s = n; then reconsider F2i = F2.i as Element of D*; now let j be Nat; assume 1 <= j & j <= len F1i; then j in Seg n by P6; hence F1i.j = F2i.j by AS,P4; end; hence F1.i = F2.i by P6,R6,FINSEQ_1:14; end; hence F1 = F2 by P1,P2,FINSEQ_1:14; end; theorem LMGSEQ4: for D be non empty set, x1,x2,x3,x4 be Element of D holds <* x1,x2,x3,x4 *> is Element of (4-tuples_on D) proof let D be non empty set, x1,x2,x3,x4 be Element of D; reconsider x1234 = <* x1,x2,x3,x4 *> as FinSequence of D; P1: len x1234 = 4 by FINSEQ_4:76; x1234 in D* by FINSEQ_1:def 11; then x1234 in 4-tuples_on D by P1; hence thesis; end; theorem LMGSEQ5: for D be non empty set,x1,x2,x3,x4,x5 be Element of D holds <* x1,x2,x3,x4,x5 *> is Element of (5-tuples_on D) proof let D be non empty set, x1,x2,x3,x4,x5 be Element of D; reconsider x12345 = <* x1,x2,x3,x4,x5 *> as FinSequence of D; P1: len x12345 = 5 by FINSEQ_4:78; x12345 in D* by FINSEQ_1:def 11; then x12345 in 5-tuples_on D by P1; hence thesis; end; theorem for D be non empty set, x1,x2,x3,x4,x5,x6,x7,x8 be Element of D holds <* x1,x2,x3,x4 *>^<* x5,x6,x7,x8 *> is Element of (8-tuples_on D) proof let D be non empty set,x1,x2,x3,x4,x5,x6,x7,x8 be Element of D; reconsider x1234 = <* x1,x2,x3,x4 *> as Element of 4-tuples_on D by LMGSEQ4; reconsider x5678 = <* x5,x6,x7,x8 *> as Element of 4-tuples_on D by LMGSEQ4; D c= D; hence thesis by FINSEQ_2:109; end; theorem LMGSEQ10: for D be non empty set, x1,x2,x3,x4,x5,x6,x7,x8,x9,x10 be Element of D holds <* x1,x2,x3,x4,x5 *>^<* x6,x7,x8,x9,x10 *> is Element of (10-tuples_on D) proof let D be non empty set, x1,x2,x3,x4,x5,x6,x7,x8,x9,x10 be Element of D; reconsider x12345 = <* x1,x2,x3,x4,x5 *> as Element of 5-tuples_on D by LMGSEQ5; reconsider x67890 = <* x6,x7,x8,x9,x10 *> as Element of 5-tuples_on D by LMGSEQ5; D c= D; hence thesis by FINSEQ_2:109; end; theorem LMGSEQ16: for D be non empty set, x1,x2,x3,x4,x5,x6,x7,x8 be Element of (4-tuples_on D) holds <* x1^x5,x2^x6,x3^x7,x4^x8 *> is Element of 4-tuples_on (8-tuples_on D) proof let D be non empty set, x1,x2,x3,x4,x5,x6,x7,x8 be Element of (4-tuples_on D); X1: D c= D; then P1: x1^x5 is Element of 8-tuples_on D by FINSEQ_2:109; P2: x2^x6 is Element of 8-tuples_on D by X1,FINSEQ_2:109; P3: x3^x7 is Element of 8-tuples_on D by X1,FINSEQ_2:109; x4^x8 is Element of 8-tuples_on D by X1,FINSEQ_2:109; hence thesis by P1,P2,P3,LMGSEQ4; end; theorem for D be non empty set, x be Element of 4-tuples_on(4-tuples_on D), k be Element of NAT st k in Seg 4 holds ex x1,x2,x3,x4 be Element of D st x1 = (x.k).1 & x2 = (x.k).2 & x3 = (x.k).3 & x4 = (x.k).4 proof let D be non empty set, x be Element of 4-tuples_on(4-tuples_on D), k be Element of NAT; assume AS: k in Seg 4; x in 4-tuples_on(4-tuples_on D); then ex s be Element of (4-tuples_on D)* st x = s & len s = 4; then k in dom x by AS,FINSEQ_1:def 3; then x.k in rng x by FUNCT_1:3; then x.k in 4-tuples_on (D); then Q13: ex s be Element of D* st x.k = s & len s = 4; then reconsider xk = x.k as Element of D*; 1 in Seg 4; then 1 in dom xk by Q13,FINSEQ_1:def 3; then xk.1 in rng xk by FUNCT_1:3; then reconsider x1 = xk.1 as Element of D; 2 in Seg 4; then 2 in dom xk by Q13,FINSEQ_1:def 3; then xk.2 in rng xk by FUNCT_1:3; then reconsider x2 = xk.2 as Element of D; 3 in Seg 4; then 3 in dom xk by Q13,FINSEQ_1:def 3; then xk.3 in rng xk by FUNCT_1:3; then reconsider x3 = xk.3 as Element of D; 4 in Seg 4; then 4 in dom xk by Q13,FINSEQ_1:def 3; then xk.4 in rng xk by FUNCT_1:3; then reconsider x4 = xk.4 as Element of D; take x1,x2,x3,x4; thus thesis; end; theorem INV00: for X,Y be non empty set, f be Function of X,Y, g be Function of Y,X st (for x be Element of X holds g.(f.x) = x) & (for y be Element of Y holds f.(g.y) = y) holds f is one-to-one & f is onto & g is one-to-one & g is onto & g = f" & f = g" proof let X,Y be non empty set, f be Function of X,Y, g be Function of Y,X; assume A1: for x be Element of X holds g.(f.x) = x; assume A2: for y be Element of Y holds f.(g.y) = y; now let x be Element of X; thus (g*f).x = g.(f.x) by FUNCT_2:15 .= x by A1; end; then P2: g*f = id X by FUNCT_2:124; now let y be Element of Y; thus (f*g).y = f.(g.y) by FUNCT_2:15 .= y by A2; end; then P4: f*g = id Y by FUNCT_2:124; thus P5: f is one-to-one & f is onto by P2,P4,FUNCT_2:23; thus P6: g is one-to-one & g is onto by P2,P4,FUNCT_2:23; rng f = Y by P5,FUNCT_2:def 3; hence g = f" by FUNCT_2:30,P2,FUNCT_2:23; rng g = X by P6,FUNCT_2:def 3; hence f = g" by FUNCT_2:30,P4,FUNCT_2:23; end; begin :: State array definition func AES-Statearray -> Function of 128-tuples_on BOOLEAN, 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) means :DefStatearray: for input be Element of 128-tuples_on BOOLEAN for i,j be Nat st i in Seg 4 & j in Seg 4 holds ((it.input).i).j = mid (input,1+(i-'1)*8+(j-'1)*32, 1+(i-'1)*8+(j-'1)*32+7); existence proof defpred P0[Element of 128-tuples_on BOOLEAN,set] means ex z be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st $2 = z & for i,j be Nat st i in Seg 4 & j in Seg 4 holds (z.i).j = mid ($1,1+(i-'1)*8+(j-'1)*32,1+(i-'1)*8+(j-'1)*32+7); A1: for x being Element of 128-tuples_on BOOLEAN ex z be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st P0[x,z] proof let x be Element of 128-tuples_on BOOLEAN; x in 128-tuples_on BOOLEAN; then A01: ex s be Element of (BOOLEAN)* st x = s & len s = 128; defpred P[Nat,set] means ex zi be Element of (4-tuples_on (8-tuples_on BOOLEAN)) st $2 = zi & for j be Nat st j in Seg 4 holds zi.j = mid (x,1+($1-'1)*8+(j-'1)*32,1+($1-'1)*8+(j-'1)*32+7); Q1: for k be Nat st k in Seg 4 ex x being Element of (4-tuples_on (8-tuples_on BOOLEAN)) st P[k,x] proof let k be Nat; assume k in Seg 4; then Q110: 1 <= k & k <= 4 by FINSEQ_1:1; then 1-1 <= k-1 by XREAL_1:9; then k-'1 = k-1 by XREAL_0:def 2; then k-'1 <= 4-1 by Q110,XREAL_1:9; then Q112: (k-'1)*8 <= 3*8 by XREAL_1:64; defpred Pi[Nat,set] means $2 = mid (x,1+(k-'1)*8+($1-'1)*32,1+(k-'1)*8+($1-'1)*32+7); Q12: for j be Nat st j in Seg 4 ex xi being Element of (8-tuples_on BOOLEAN) st Pi[j,xi] proof let j be Nat; assume j in Seg 4; then Q130: 1 <= j & j <= 4 by FINSEQ_1:1; then 1-1 <= j-1 by XREAL_1:9; then j-'1 = j-1 by XREAL_0:def 2; then j-'1 <= 4-1 by Q130,XREAL_1:9; then Q133: (j-'1)*32 <= 3*32 by XREAL_1:64; (k-'1)*8+(j-'1)*32 <= 24+96 by Q133,Q112,XREAL_1:7; then Q134: 1+((k-'1)*8+(j-'1)*32) <= 1+120 by XREAL_1:7; Q136: (1+(k-'1)*8+(j-'1)*32)+7 <= 121+7 by Q134,XREAL_1:7; 1+0 <= 1+((k-'1)*8+(j-'1)*32) by XREAL_1:7; then Q14: 1 <= 1+(k-'1)*8+(j-'1)*32 & 1+(k-'1)*8+(j-'1)*32 <= len x by Q134,XXREAL_0:2,A01; Q150: 1+0 <= 1+(k-'1)*8+(j-'1)*32+7 by XREAL_1:7; reconsider mmd = mid (x,1+(k-'1)*8+(j-'1)*32, 1+(k-'1)*8+(j-'1)*32+7) as Element of (BOOLEAN)* by FINSEQ_1:def 11; 1+(k-'1)*8+(j-'1)*32+0 <= 1+(k-'1)*8+(j-'1)*32+7 by XREAL_1:6; then len mid (x,1+(k-'1)*8+(j-'1)*32,1+(k-'1)*8+(j-'1)*32+7) = (1+(k-'1)*8+(j-'1)*32+7)-'(1+(k-'1)*8+(j-'1)*32)+1 by FINSEQ_6:118,Q14,Q136,A01,Q150 .= 7+1 by NAT_D:34 .= 8; then mmd in (8-tuples_on BOOLEAN); then reconsider xi = mid (x,1+(k-'1)*8+(j-'1)*32, 1+(k-'1)*8+(j-'1)*32+7) as Element of (8-tuples_on BOOLEAN); xi = mid (x,1+(k-'1)*8+(j-'1)*32,1+(k-'1)*8+(j-'1)*32+7); hence thesis; end; consider zi be FinSequence of (8-tuples_on BOOLEAN) such that Q13: dom zi = Seg 4 & for i be Nat st i in Seg 4 holds Pi[i,zi.i] from FINSEQ_1:sch 5(Q12); Q14: len zi = 4 by Q13,FINSEQ_1:def 3; reconsider zi as Element of (8-tuples_on BOOLEAN)* by FINSEQ_1:def 11; zi in 4-tuples_on (8-tuples_on BOOLEAN) by Q14; then reconsider zi as Element of 4-tuples_on (8-tuples_on BOOLEAN); for j be Nat st j in Seg 4 holds zi.j = mid (x,1+(k-'1)*8+(j-'1)*32,1+(k-'1)*8+(j-'1)*32+7) by Q13; hence thesis; end; consider z be FinSequence of 4-tuples_on (8-tuples_on BOOLEAN) such that Q2: dom z = Seg 4 & for i be Nat st i in Seg 4 holds P[i,z.i] from FINSEQ_1:sch 5(Q1); Q3: len z = 4 by Q2,FINSEQ_1:def 3; reconsider z as Element of (4-tuples_on (8-tuples_on BOOLEAN))* by FINSEQ_1:def 11; z in 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN))by Q3; then reconsider z as Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); for i,j be Nat st i in Seg 4 & j in Seg 4 holds (z.i).j = mid (x,1+(i-'1)*8+(j-'1)*32,1+(i-'1)*8+(j-'1)*32+7) proof let i,j be Nat; assume P11: i in Seg 4 & j in Seg 4; then consider zi be Element of (4-tuples_on (8-tuples_on BOOLEAN)) such that P12: z.i = zi & for j be Nat st j in Seg 4 holds zi.j = mid (x,1+(i-'1)*8+(j-'1)*32,1+(i-'1)*8+(j-'1)*32+7) by Q2; thus (z.i).j = mid (x,1+(i-'1)*8+(j-'1)*32,1+(i-'1)*8+(j-'1)*32+7) by P11,P12; end; hence ex z be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st P0[x,z]; end; consider I be Function of 128-tuples_on BOOLEAN, 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) such that A2: for x being Element of 128-tuples_on BOOLEAN holds P0[x,I.x] from FUNCT_2:sch 3(A1); now let input be Element of 128-tuples_on BOOLEAN; ex z be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st I.input = z & for i,j be Nat st i in Seg 4 & j in Seg 4 holds (z.i).j = mid (input,1+(i-'1)*8+(j-'1)*32,1+(i-'1)*8+(j-'1)*32+7) by A2; hence for i,j be Nat st i in Seg 4 & j in Seg 4 holds ((I.input).i).j = mid (input,1+(i-'1)*8+(j-'1)*32, 1+(i-'1)*8+(j-'1)*32+7); end; hence thesis; end; uniqueness proof let H1,H2 be Function of 128-tuples_on BOOLEAN, 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); assume A1: for input be Element of 128-tuples_on BOOLEAN for i,j be Nat st i in Seg 4 & j in Seg 4 holds ((H1.input).i).j = mid (input,1+(i-'1)*8+(j-'1)*32, 1+(i-'1)*8+(j-'1)*32+7); assume A2: for input be Element of 128-tuples_on BOOLEAN for i,j be Nat st i in Seg 4 & j in Seg 4 holds ((H2.input).i).j = mid (input,1+(i-'1)*8+(j-'1)*32, 1+(i-'1)*8+(j-'1)*32+7); now let input be Element of 128-tuples_on BOOLEAN; (H1.input) in 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); then P3: ex s be Element of (4-tuples_on (8-tuples_on BOOLEAN))* st (H1.input) = s & len s = 4; (H2.input) in 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); then P4: ex s be Element of (4-tuples_on (8-tuples_on BOOLEAN))* st (H2.input) = s & len s = 4; now let i be Nat; assume 1 <=i & i <= len (H1.input); then P6: i in Seg 4 by P3; then i in dom(H1.input) by FINSEQ_1:def 3,P3; then (H1.input).i in rng (H1.input) by FUNCT_1:3; then (H1.input).i in 4-tuples_on (8-tuples_on BOOLEAN); then P8: ex s be Element of (8-tuples_on BOOLEAN)* st (H1.input).i = s & len s = 4; reconsider H1i = (H1.input).i as Element of (8-tuples_on BOOLEAN)* by P8; i in dom(H2.input) by FINSEQ_1:def 3,P4,P6; then (H2.input).i in rng (H2.input) by FUNCT_1:3; then (H2.input).i in 4-tuples_on (8-tuples_on BOOLEAN); then P11: ex s be Element of (8-tuples_on BOOLEAN)* st (H2.input).i = s & len s = 4; reconsider H2i = (H2.input).i as Element of (8-tuples_on BOOLEAN)* by P11; now let j be Nat; assume 1 <=j & j <= len H1i; then P14: j in Seg 4 by P8; then ((H1.input).i).j = mid (input,1+(i-'1)*8+(j-'1)*32, 1+(i-'1)*8+(j-'1)*32+7) by A1,P6; hence H1i.j = H2i.j by A2,P6,P14; end; hence (H1.input).i = (H2.input).i by P8,P11,FINSEQ_1:def 17; end; hence H1.input = H2.input by P3,P4,FINSEQ_1:def 17; end; hence H1 = H2 by FUNCT_2:63; end; end; theorem LMStat0: for k be Nat st 1 <= k & k <= 128 ex i,j be Nat st i in Seg 4 & j in Seg 4 & 1+(i-'1)*8+(j-'1)*32 <= k & k <= 1+(i-'1)*8+(j-'1)*32+7 proof let k be Nat; assume A1: 1 <= k & k <= 128; A3: k = 32*(k div 32)+(k mod 32) by NAT_D:2; reconsider m = k div 32 as Nat; reconsider n = k mod 32 as Nat; k div 32 <= (32*4) div 32 by A1,NAT_2:24; then M1: m <= 4 by NAT_D:18; per cases; suppose A4: n = 0; A5: 1 <= m proof assume not 1 <= m; then m = 0 by NAT_1:14; hence contradiction by A1,A3,A4; end; set j = m; A8: j in Seg 4 by M1,A5; set i = 4; A10: i in Seg 4; A11: j-'1 = j-1 by XREAL_1:233,A5; A13: k = 32*(k div 32)+(k mod 32) by NAT_D:2 .= 32*(j-'1)+8*((i-1)+1) by A4,A11 .= 32*(j-'1)+8*((i-'1)+1) by XREAL_1:233 .= 1+(i-'1)*8+(j-'1)*32+7; 1+(i-'1)*8+(j-'1)*32+0 <= 1+(i-'1)*8+(j-'1)*32+7 by XREAL_1:7; hence ex i,j be Nat st i in Seg 4 & j in Seg 4 & 1+(i-'1)*8+(j-'1)*32 <= k & k <= 1+(i-'1)*8+(j-'1)*32+7 by A8,A10,A13; end; suppose A14: n <> 0; then XX0: 1 <= n by NAT_1:14; XX1: n <= 32 by NAT_D:1; m <> 4 proof assume U1: m = 4; U2: k = 32*4+n by NAT_D:2,U1 .= 128+n; 128+1 <= 128+n by XX0,XREAL_1:7; hence contradiction by U2,XXREAL_0:2,A1; end; then m < 4 by XXREAL_0:1,M1; then A15: m+1 <= 4 by NAT_1:13; A16: 1 <= m+1 by NAT_1:11; set j = m+1; A18: j in Seg 4 by A15,A16; A19: j-'1 = j-1 by XREAL_1:233,NAT_1:11 .=m; A20: k = 32*(j-'1)+n by NAT_D:2,A19; A22: n = 8*(n div 8)+(n mod 8) by NAT_D:2; reconsider s = n div 8 as Nat; reconsider t = n mod 8 as Nat; n div 8 <= (8*4) div 8 by XX1,NAT_2:24; then M2: n div 8 <= 4 by NAT_D:18; now per cases; suppose A23: t = 0; A24: 1 <= s proof assume not 1 <= s; then n = 8*0+0 by NAT_1:14,A22,A23; hence contradiction by A14; end; set i = s; A28: i in Seg 4 by M2,A24; A29: i-'1 = i-1 by XREAL_1:233,A24; A30: n = 8*s+0 by NAT_D:2,A23 .= 8*(i-'1)+8*1 by A29; 1+(i-'1)*8+(j-'1)*32+0 <= 1+(i-'1)*8+(j-'1)*32+7 by XREAL_1:7; hence ex i,j be Nat st i in Seg 4 & j in Seg 4 & 1+(i-'1)*8+(j-'1)*32 <= k & k <= 1+(i-'1)*8+(j-'1)*32+7 by A28,A18,A20,A30; end; suppose t <> 0; then XX0: 1 <= t by NAT_1:14; XXX1: t <= 8 by NAT_D:1; s <> 4 proof assume U1: s = 4; U2: n = 8*4+t by NAT_D:2,U1 .= 32+t; 32+1 <= 32+t by XX0,XREAL_1:7; hence contradiction by U2,XXREAL_0:2,XX1; end; then s < 4 by XXREAL_0:1,M2; then B15: s+1 <= 4 by NAT_1:13; B16: 1 <= s+1 by NAT_1:11; set i = s+1; B18: i in Seg 4 by B15,B16; B19: i-'1 = i-1 by XREAL_1:233,NAT_1:11 .=s; B20: n = 8*(i-'1)+t by NAT_D:2,B19; B220: 32*(j-'1)+8*(i-'1)+1 <= 32*(j-'1)+8*(i-'1)+t by XX0,XREAL_1:7; 32*(j-'1)+8*(i-'1)+t <= 32*(j-'1)+8*(i-'1)+8 by XXX1,XREAL_1:7; then k <= 1+8*(i-'1)+32*(j-'1)+7 by A20,B20; hence ex i,j be Nat st i in Seg 4 & j in Seg 4 & 1+(i-'1)*8+(j-'1)*32 <= k & k <= 1+(i-'1)*8+(j-'1)*32+7 by B220,A20,B20,B18,A18; end; end; hence ex i,j be Nat st i in Seg 4 & j in Seg 4 & 1+(i-'1)*8+(j-'1)*32 <= k & k <= 1+(i-'1)*8+(j-'1)*32+7; end; end; theorem LMStat2A: for i,j,i0,j0 be Nat st i in Seg 4 & j in Seg 4 & i0 in Seg 4 & j0 in Seg 4 & not (i = i0 & j = j0) holds {k where k is Nat : 1+(i-'1)*8+(j-'1)*32 <= k & k <= 8+(i-'1)*8+(j-'1)*32} /\ {k where k is Nat : 1+(i0-'1)*8+(j0-'1)*32 <= k & k <= 8+(i0-'1)*8+(j0-'1)*32} = {} proof let i,j,i0,j0 be Nat; assume AS: i in Seg 4 & j in Seg 4 & i0 in Seg 4 & j0 in Seg 4 & not (i = i0 & j = j0); set A = {k where k is Nat : 1+(i-'1)*8+(j-'1)*32 <= k & k <= 8+(i-'1)*8+(j-'1)*32}; set B = {k where k is Nat : 1+(i0-'1)*8+(j0-'1)*32 <= k & k <= 8+(i0-'1)*8+(j0-'1)*32}; A1: 1 <= j & j <= 4 by AS,FINSEQ_1:1; A2: 1 <= i & i <= 4 by AS,FINSEQ_1:1; B1: 1 <= j0 & j0 <= 4 by AS,FINSEQ_1:1; B2: 1 <= i0 & i0 <= 4 by AS,FINSEQ_1:1; P1: (j-'1) = j-1 by XREAL_1:233,A1; P2: (i-'1) = i-1 by XREAL_1:233,A2; P3: (j0-'1) = j0-1 by XREAL_1:233,B1; P4: (i0-'1) = i0-1 by XREAL_1:233,B2; i-1 <= 4-1 by A2,XREAL_1:9; then R2: i-'1 <= 3 by XREAL_1:233,A2; i0-1 <= 4-1 by B2,XREAL_1:9; then R4: i0-'1 <= 3 by XREAL_1:233,B2; per cases; suppose A2: j <> j0; now per cases by A2,XXREAL_0:1; suppose j < j0; then (j-'1) < (j0-'1) by XREAL_1:14,P1,P3; then (j-'1)+1 <= (j0-'1) by NAT_1:13; then A12: ((j-'1)+1)*32 <= (j0-'1)*32 by XREAL_1:64; (i-'1)*8 <= 3*8 by R2,XREAL_1:64; then 8+(i-'1)*8 <= 8+24 by XREAL_1:6; then 8+(i-'1)*8+(j-'1)*32 <= 32+(j-'1)*32 by XREAL_1:6; then A13: 8+(i-'1)*8+(j-'1)*32 <= (j0-'1)*32 by A12,XXREAL_0:2; 0+(j0-'1)*32 <= (i0-'1)*8+(j0-'1)*32 by XREAL_1:6; then (j0-'1)*32+0 < (i0-'1)*8+(j0-'1)*32+1 by XREAL_1:8; then A14: 8+(i-'1)*8+(j-'1)*32 < 1+(i0-'1)*8+(j0-'1)*32 by A13,XXREAL_0:2; thus A /\ B = {} proof assume A /\ B <> {}; then consider x be object such that A150: x in A /\ B by XBOOLE_0:def 1; A15: x in A & x in B by XBOOLE_0:def 4,A150; consider k1 be Nat such that A16: x = k1 & 1+(i-'1)*8+(j-'1)*32 <= k1 & k1 <= 8+(i-'1)*8+(j-'1)*32 by A15; consider k2 be Nat such that A17: x = k2 & 1+(i0-'1)*8+(j0-'1)*32 <= k2 & k2 <= 8+(i0-'1)*8+(j0-'1)*32 by A15; reconsider x as Nat by A16; thus contradiction by A17,A14,XXREAL_0:2,A16; end; end; suppose j0 < j; then (j0-'1) < (j-'1) by XREAL_1:14,P1,P3; then (j0-'1)+1 <= (j-'1) by NAT_1:13; then A12: ((j0-'1)+1)*32 <= (j-'1)*32 by XREAL_1:64; (i0-'1)*8 <= 3*8 by R4,XREAL_1:64; then 8+(i0-'1)*8 <= 8+24 by XREAL_1:6; then 8+(i0-'1)*8+(j0-'1)*32 <= 32+(j0-'1)*32 by XREAL_1:6; then A13: 8+(i0-'1)*8+(j0-'1)*32 <= (j-'1)*32 by A12,XXREAL_0:2; 0+(j-'1)*32 <= (i-'1)*8+(j-'1)*32 by XREAL_1:6; then (j-'1)*32+0 < (i-'1)*8+(j-'1)*32+1 by XREAL_1:8; then A14: 8+(i0-'1)*8+(j0-'1)*32 < 1+(i-'1)*8+(j-'1)*32 by A13,XXREAL_0:2; thus A /\ B = {} proof assume A /\ B <> {}; then consider x be object such that A150: x in A /\ B by XBOOLE_0:def 1; A15: x in A & x in B by XBOOLE_0:def 4,A150; consider k1 be Nat such that A16: x = k1 & 1+(i-'1)*8+(j-'1)*32 <= k1 & k1 <= 8+(i-'1)*8+(j-'1)*32 by A15; consider k2 be Nat such that A17: x = k2 & 1+(i0-'1)*8+(j0-'1)*32 <= k2 & k2 <= 8+(i0-'1)*8+(j0-'1)*32 by A15; reconsider x as Nat by A16; thus contradiction by A16,A14,XXREAL_0:2,A17; end; end; end; hence A /\ B = {}; end; suppose A2: j = j0; now per cases by A2,AS,XXREAL_0:1; suppose i < i0; then (i-'1) < (i0-'1) by XREAL_1:14,P2,P4; then (i-'1)+1 <= (i0-'1) by NAT_1:13; then ((i-'1)+1)*8 <= (i0-'1)*8 by XREAL_1:64; then A13: (i-'1)*8+8+(j-'1)*32 <= (i0-'1)*8+(j0-'1)*32 by A2,XREAL_1:6; (i0-'1)*8+(j0-'1)*32+0 < (i0-'1)*8+(j0-'1)*32+1 by XREAL_1:8; then A14: 8+(i-'1)*8+(j-'1)*32 < 1+(i0-'1)*8+(j0-'1)*32 by A13,XXREAL_0:2; thus A /\ B = {} proof assume A /\ B <> {}; then consider x be object such that A150: x in A /\ B by XBOOLE_0:def 1; A15: x in A & x in B by XBOOLE_0:def 4,A150; consider k1 be Nat such that A16: x = k1 & 1+(i-'1)*8+(j-'1)*32 <= k1 & k1 <= 8+(i-'1)*8+(j-'1)*32 by A15; consider k2 be Nat such that A17: x = k2 & 1+(i0-'1)*8+(j0-'1)*32 <= k2 & k2 <= 8+(i0-'1)*8+(j0-'1)*32 by A15; reconsider x as Nat by A16; thus contradiction by A16,A17,A14,XXREAL_0:2; end; end; suppose i0 < i; then (i0-'1) < (i-'1) by XREAL_1:14,P2,P4; then (i0-'1)+1 <= (i-'1) by NAT_1:13; then ((i0-'1)+1)*8 <= (i-'1)*8 by XREAL_1:64; then A13: (i0-'1)*8+8+(j0-'1)*32 <= (i-'1)*8+(j-'1)*32 by A2,XREAL_1:6; (i-'1)*8+(j-'1)*32+0 < (i-'1)*8+(j-'1)*32+1 by XREAL_1:8; then A14: 8+(i0-'1)*8+(j0-'1)*32 < 1+(i-'1)*8+(j-'1)*32 by A13,XXREAL_0:2; thus A /\ B = {} proof assume A /\ B <> {}; then consider x be object such that A150: x in A /\ B by XBOOLE_0:def 1; A15: x in A & x in B by XBOOLE_0:def 4,A150; consider k1 be Nat such that A16: x = k1 & 1+(i-'1)*8+(j-'1)*32 <= k1 & k1 <= 8+(i-'1)*8+(j-'1)*32 by A15; consider k2 be Nat such that A17: x = k2 & 1+(i0-'1)*8+(j0-'1)*32 <= k2 & k2 <= 8+(i0-'1)*8+(j0-'1)*32 by A15; reconsider x as Nat by A16; thus contradiction by A16,A14,XXREAL_0:2,A17; end; end; end; hence A /\ B = {}; end; end; theorem LMStat2: for k,i,j,i0,j0 be Nat st 1 <= k & k <= 128 & i in Seg 4 & j in Seg 4 & i0 in Seg 4 & j0 in Seg 4 & 1+(i-'1)*8+(j-'1)*32 <= k & k <= 1+(i-'1)*8+(j-'1)*32+7 & 1+(i0-'1)*8+(j0-'1)*32 <= k & k <= 1+(i0-'1)*8+(j0-'1)*32+7 holds i = i0 & j = j0 proof let k,i,j,i0,j0 be Nat; assume AS: 1 <= k & k <= 128 & i in Seg 4 & j in Seg 4 & i0 in Seg 4 & j0 in Seg 4 & 1+(i-'1)*8+(j-'1)*32 <= k & k <= 1+(i-'1)*8+(j-'1)*32+7 & 1+(i0-'1)*8+(j0-'1)*32 <= k & k <= 1+(i0-'1)*8+(j0-'1)*32+7; assume not (i = i0 & j = j0); then A2: {n where n is Nat : 1+(i-'1)*8+(j-'1)*32 <= n & n <= 8+(i-'1)*8+(j-'1)*32} /\ {n where n is Nat : 1+(i0-'1)*8+(j0-'1)*32 <= n & n <= 8+(i0-'1)*8+(j0-'1)*32} = {} by LMStat2A,AS; A3: k in {n where n is Nat : 1+(i-'1)*8+(j-'1)*32 <= n & n <= 8+(i-'1)*8+(j-'1)*32} by AS; k in {n where n is Nat : 1+(i0-'1)*8+(j0-'1)*32 <= n & n <= 8+(i0-'1)*8+(j0-'1)*32} by AS; hence contradiction by A3,XBOOLE_0:def 4,A2; end; theorem LMStat1: AES-Statearray is one-to-one proof for x1,x2 be object st x1 in 128-tuples_on BOOLEAN & x2 in 128-tuples_on BOOLEAN & (AES-Statearray).x1 = (AES-Statearray).x2 holds x1 = x2 proof let x1,x2 be object; assume A1: x1 in 128-tuples_on BOOLEAN & x2 in 128-tuples_on BOOLEAN & (AES-Statearray).x1 = (AES-Statearray).x2; then reconsider xx1 = x1,xx2 = x2 as Element of 128-tuples_on BOOLEAN; P1: ex s be Element of (BOOLEAN)* st xx1 = s & len s = 128 by A1; P2: ex s be Element of (BOOLEAN)* st xx2 = s & len s = 128 by A1; now let k be Nat; assume P5: 1 <= k & k <= len xx1; consider i,j be Nat such that A4: i in Seg 4 & j in Seg 4 & 1+(i-'1)*8+(j-'1)*32 <= k & k <= 1+(i-'1)*8+(j-'1)*32+7 by LMStat0,P5,P1; mid (xx1,1+(i-'1)*8+(j-'1)*32,1+(i-'1)*8+(j-'1)*32+7) is Element of (BOOLEAN)* by FINSEQ_1:def 11; then reconsider A1ij = (((AES-Statearray).xx1).i).j as FinSequence of (BOOLEAN) by DefStatearray,A4; mid (xx2,1+(i-'1)*8+(j-'1)*32,1+(i-'1)*8+(j-'1)*32+7) is Element of (BOOLEAN)* by FINSEQ_1:def 11; then reconsider A2ij = (((AES-Statearray).xx2).i).j as FinSequence of (BOOLEAN) by DefStatearray,A4; A50: 1+(i-'1)*8+(j-'1)*32-((i-'1)*8+(j-'1)*32) <= k-((i-'1)*8+(j-'1)*32) by A4,XREAL_1:9; then reconsider n = k-((i-'1)*8+(j-'1)*32) as Element of NAT by INT_1:3; F41: k-((i-'1)*8+(j-'1)*32) <= 1+(i-'1)*8+(j-'1)*32+7-((i-'1)*8+(j-'1)*32) by A4,XREAL_1:9; F1: 1 <= 1+((i-'1)*8+(j-'1)*32) by NAT_1:11; F2: 1+(i-'1)*8+(j-'1)*32 <= 1+(i-'1)*8+(j-'1)*32+7 by NAT_1:11; Q110: 1 <= i & i <= 4 by A4,FINSEQ_1:1; then 1-1 <= i-1 by XREAL_1:9; then i-'1 = i-1 by XREAL_0:def 2; then i-'1 <= 4-1 by Q110,XREAL_1:9; then Q112: (i-'1)*8 <= 3*8 by XREAL_1:64; Q130: 1 <= j & j <= 4 by A4,FINSEQ_1:1; then 1-1 <= j-1 by XREAL_1:9; then j-'1 = j-1 by XREAL_0:def 2; then j-'1 <= 4-1 by Q130,XREAL_1:9; then Q133: (j-'1)*32 <= 3*32 by XREAL_1:64; (i-'1)*8+(j-'1)*32 <= 24+96 by Q133,Q112,XREAL_1:7; then 1+((i-'1)*8+(j-'1)*32) <= 1+120 by XREAL_1:7; then Q135: 1+(i-'1)*8+(j-'1)*32+7 <= 121+7 by XREAL_1:6; F5: n <= (1+(i-'1)*8+(j-'1)*32+7)-(1+(i-'1)*8+(j-'1)*32)+1 by F41; A6: k = n-1+(1+(i-'1)*8+(j-'1)*32); thus xx1.k = (mid (xx1,1+(i-'1)*8+(j-'1)*32,1+(i-'1)*8+(j-'1)*32+7)).n by F1,F2,Q135,P1,A50,F5,A6,FINSEQ_6:122 .= A2ij.n by DefStatearray,A4,A1 .= (mid (xx2,1+(i-'1)*8+(j-'1)*32,1+(i-'1)*8+(j-'1)*32+7)).n by DefStatearray,A4 .= xx2.k by F1,F2,P2,Q135,A50,F5,A6,FINSEQ_6:122; end; hence thesis by P1,P2,FINSEQ_1:def 17; end; hence thesis by FUNCT_2:19; end; theorem LMStat3: AES-Statearray is onto proof for y be object st y in 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) ex x be object st x in 128-tuples_on BOOLEAN & y = AES-Statearray.x proof let y be object; assume y in 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); then B10:ex s be Element of (4-tuples_on (8-tuples_on BOOLEAN))* st y = s & len s = 4; then reconsider z = y as Element of (4-tuples_on (8-tuples_on BOOLEAN))*; defpred PK[Nat,set] means ex i,j,n be Nat, zij be Element of (8-tuples_on BOOLEAN) st i in Seg 4 & j in Seg 4 & n in Seg 8 & 1+(i-'1)*8+(j-'1)*32 <= $1 & $1 <= 1+(i-'1)*8+(j-'1)*32+7 & n = $1-((i-'1)*8+(j-'1)*32) & zij = (z.i).j & $2 = zij.n; Q12: for k be Nat st k in Seg 128 ex z being Element of BOOLEAN st PK[k,z] proof let k be Nat; assume k in Seg 128; then 1 <= k & k <= 128 by FINSEQ_1:1; then consider i,j be Nat such that A4: i in Seg 4 & j in Seg 4 & 1+(i-'1)*8+(j-'1)*32 <= k & k <= 1+(i-'1)*8+(j-'1)*32+7 by LMStat0; i in dom z by FINSEQ_1:def 3,A4,B10; then z.i in rng z by FUNCT_1:3; then z.i in 4-tuples_on (8-tuples_on BOOLEAN); then B10: ex s be Element of (8-tuples_on BOOLEAN)* st z.i = s & len s = 4; then reconsider zi = z.i as Element of (8-tuples_on BOOLEAN)*; j in dom zi by B10,FINSEQ_1:def 3,A4; then (zi).j in rng zi by FUNCT_1:3; then reconsider zij = (z.i).j as Element of 8-tuples_on BOOLEAN; A50: 1+(i-'1)*8+(j-'1)*32-((i-'1)*8+(j-'1)*32) <= k-((i-'1)*8+(j-'1)*32) by A4,XREAL_1:9; then reconsider n = k-((i-'1)*8+(j-'1)*32) as Element of NAT by INT_1:3; k-((i-'1)*8+(j-'1)*32) <= 1+(i-'1)*8+(j-'1)*32+7-((i-'1)*8+(j-'1)*32) by A4,XREAL_1:9; then G4: n in Seg 8 by A50; reconsider z = zij.n as Element of BOOLEAN; take z; thus thesis by A4,G4; end; consider x be FinSequence of BOOLEAN such that Q13: dom x = Seg 128 & for i be Nat st i in Seg 128 holds PK[i,x.i] from FINSEQ_1:sch 5(Q12); Q14: len x = 128 by Q13,FINSEQ_1:def 3; reconsider x as Element of (BOOLEAN)* by FINSEQ_1:def 11; x in 128-tuples_on BOOLEAN by Q14; then reconsider x as Element of 128-tuples_on BOOLEAN; P2: for i,j be Nat st i in Seg 4 & j in Seg 4 holds (z.i).j = mid (x,1+(i-'1)*8+(j-'1)*32,1+(i-'1)*8+(j-'1)*32+7) proof let i,j be Nat; assume P21: i in Seg 4 & j in Seg 4; then i in dom z by FINSEQ_1:def 3,B10; then z.i in rng z by FUNCT_1:3; then z.i in 4-tuples_on (8-tuples_on BOOLEAN); then P8: ex s be Element of (8-tuples_on BOOLEAN)* st z.i = s & len s = 4; reconsider zi = z.i as Element of (8-tuples_on BOOLEAN)* by P8; j in dom zi by P8,FINSEQ_1:def 3,P21; then zi.j in rng zi by FUNCT_1:3; then zi.j in (8-tuples_on BOOLEAN); then P11: ex s be Element of (BOOLEAN)* st zi.j = s & len s = 8; reconsider zij = zi.j as Element of (BOOLEAN)* by P11; Q110: 1 <= i & i <= 4 by P21,FINSEQ_1:1; then 1-1 <= i-1 by XREAL_1:9; then i-'1 = i-1 by XREAL_0:def 2; then i-'1 <= 4-1 by Q110,XREAL_1:9; then Q112: (i-'1)*8 <= 3*8 by XREAL_1:64; Q130: 1 <= j & j <= 4 by P21,FINSEQ_1:1; then 1-1 <= j-1 by XREAL_1:9; then j-'1 = j-1 by XREAL_0:def 2; then j-'1 <= 4-1 by Q130,XREAL_1:9; then Q133: (j-'1)*32 <= 3*32 by XREAL_1:64; (i-'1)*8+(j-'1)*32 <= 24+96 by Q133,Q112,XREAL_1:7; then Q134: 1+((i-'1)*8+(j-'1)*32) <= 1+120 by XREAL_1:7; then G1: 1+((i-'1)*8+(j-'1)*32) <= len x by XXREAL_0:2,Q14; G0: 1 <= 1+((i-'1)*8+(j-'1)*32) by NAT_1:11; G2: 1 <= 1+((i-'1)*8+(j-'1)*32+7) by NAT_1:11; G3: 1+((i-'1)*8+(j-'1)*32)+0 <= 1+(i-'1)*8+(j-'1)*32+7 by XREAL_1:7; Q135: 1+(i-'1)*8+(j-'1)*32+7 <= 121+7 by XREAL_1:6,Q134; then F3: 1+(i-'1)*8+(j-'1)*32+7 <= len x by Q13,FINSEQ_1:def 3; P13: len (mid (x,1+(i-'1)*8+(j-'1)*32,1+(i-'1)*8+(j-'1)*32+7)) = (1+(i-'1)*8+(j-'1)*32+7)-'(1+(i-'1)*8+(j-'1)*32)+1 by G1,G2,G3,G0,F3,FINSEQ_6:118 .= (1+(i-'1)*8+(j-'1)*32+7)-(1+(i-'1)*8+(j-'1)*32)+1 by G3,XREAL_1:233 .= 8; now let n be Nat; assume F40: 1 <= n & n <= len zij; F1: 1 <= 1+((i-'1)*8+(j-'1)*32) by NAT_1:11; F2: 1+(i-'1)*8+(j-'1)*32 <= 1+(i-'1)*8+(j-'1)*32+7 by NAT_1:11; F5: n <= (1+(i-'1)*8+(j-'1)*32+7)-(1+(i-'1)*8+(j-'1)*32)+1 by F40,P11; reconsider k = n+((i-'1)*8+(j-'1)*32) as Nat; A6: k = n-1+(1+(i-'1)*8+(j-'1)*32); n <= n+((i-'1)*8+(j-'1)*32) by NAT_1:11; then H1: 1 <= k by F40,XXREAL_0:2; reconsider k = n+((i-'1)*8+(j-'1)*32) as Nat; H3: k <= 8+((i-'1)*8+(j-'1)*32) by F40,P11,XREAL_1:7; then H2: k <= 128 by Q135,XXREAL_0:2; then k in Seg 128 by H1; then consider i0,j0,n0 be Nat, zi0j0 be Element of (8-tuples_on BOOLEAN) such that AA1: i0 in Seg 4 & j0 in Seg 4 & n0 in Seg 8 & 1+(i0-'1)*8+(j0-'1)*32 <= k & k <= 1+(i0-'1)*8+(j0-'1)*32+7 & n0 = k-((i0-'1)*8+(j0-'1)*32) & zi0j0 = (z.i0).j0 & x.k = zi0j0.n0 by Q13; 1+((i-'1)*8+(j-'1)*32) <= n+((i-'1)*8+(j-'1)*32) by F40,XREAL_1:7; then 1+(i-'1)*8+(j-'1)*32 <= k & k <= 1+(i-'1)*8+(j-'1)*32+7 by H3; then i = i0 & j = j0 by LMStat2,AA1,P21,H1,H2; hence zij.n = (mid (x,1+(i-'1)*8+(j-'1)*32,1+(i-'1)*8+(j-'1)*32+7)).n by AA1,F1,F2,F3,F40,F5,A6,FINSEQ_6:122; end; hence thesis by FINSEQ_1:def 17,P11,P13; end; (AES-Statearray.x) in 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); then P3: ex s be Element of (4-tuples_on (8-tuples_on BOOLEAN))* st (AES-Statearray.x) = s & len s = 4; now let i be Nat; assume 1 <= i & i <= len (AES-Statearray.x); then P6: i in Seg 4 by P3; then i in dom(AES-Statearray.x) by FINSEQ_1:def 3,P3; then (AES-Statearray.x).i in rng (AES-Statearray.x) by FUNCT_1:3; then (AES-Statearray.x).i in 4-tuples_on (8-tuples_on BOOLEAN); then P8: ex s be Element of (8-tuples_on BOOLEAN)* st (AES-Statearray.x).i = s & len s = 4; reconsider H1i = (AES-Statearray.x).i as Element of (8-tuples_on BOOLEAN)* by P8; i in dom z by FINSEQ_1:def 3,B10,P6; then z.i in rng z by FUNCT_1:3; then z.i in 4-tuples_on (8-tuples_on BOOLEAN); then P11: ex s be Element of (8-tuples_on BOOLEAN)* st z.i = s & len s = 4; reconsider H2i = z.i as Element of (8-tuples_on BOOLEAN)* by P11; now let j be Nat; assume 1 <= j & j <= len H1i; then P14: j in Seg 4 by P8; then ((AES-Statearray.x).i).j = mid (x,1+(i-'1)*8+(j-'1)*32, 1+(i-'1)*8+(j-'1)*32+7) by DefStatearray,P6; hence H1i.j = H2i.j by P2,P6,P14; end; hence (AES-Statearray.x).i = z.i by P8,P11,FINSEQ_1:def 17; end; hence thesis by P3,B10,FINSEQ_1:def 17; end; then 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) = rng AES-Statearray by FUNCT_2:10; hence thesis by FUNCT_2:def 3; end; registration cluster AES-Statearray -> bijective; correctness by LMStat1,LMStat3; end; theorem LMINV1: for cipher be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds AES-Statearray.((AES-Statearray)".(cipher)) = cipher proof let cipher be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); set f = AES-Statearray; L0: rng AES-Statearray = 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) by FUNCT_2:def 3; then reconsider g = f" as Function of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)),128-tuples_on BOOLEAN by FUNCT_2:25; L2: (f")*f = id (128-tuples_on BOOLEAN) & f*(f") = id (4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN))) by FUNCT_2:29,L0; then g is one-to-one & rng g = 128-tuples_on BOOLEAN by FUNCT_2:18; then f = g" by FUNCT_2:30,L2; hence thesis by FUNCT_2:26; end; begin :: SubBytes reserve SBT for Permutation of (8-tuples_on BOOLEAN); definition let SBT; func SubBytes(SBT) -> Function of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) means :DefSubBytes: for input be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds for i,j be Nat st i in Seg 4 & j in Seg 4 holds ex inputij be Element of 8-tuples_on BOOLEAN st inputij = (input.i).j & ((it.input).i).j = SBT.(inputij); existence proof defpred P0[Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN))] means for i,j be Nat st i in Seg 4 & j in Seg 4 holds ex inputij be Element of 8-tuples_on BOOLEAN st inputij = ($1.i).j & ($2.i).j = SBT.(inputij); A1: for text being Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) ex z be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st P0[text,z] proof let text be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); text in 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); then Q01: ex s be Element of (4-tuples_on (8-tuples_on BOOLEAN))* st text = s & len s = 4; defpred P[Nat,set] means ex zk be Element of (4-tuples_on (8-tuples_on BOOLEAN)) st $2 = zk & for j be Nat st j in Seg 4 holds ex textij be Element of 8-tuples_on BOOLEAN st textij = (text.$1).j & zk.j = SBT.(textij); Q1: for k be Nat st k in Seg 4 ex zk being Element of (4-tuples_on (8-tuples_on BOOLEAN)) st P[k,zk] proof let k be Nat; assume k in Seg 4; then k in dom text by Q01,FINSEQ_1:def 3; then text.k in rng text by FUNCT_1:3; then text.k in 4-tuples_on (8-tuples_on BOOLEAN); then Q13: ex s be Element of (8-tuples_on BOOLEAN)* st text.k = s & len s = 4; then reconsider textk = text.k as Element of (8-tuples_on BOOLEAN)*; defpred Pi[Nat,set] means ex textij be Element of 8-tuples_on BOOLEAN st textij = (textk).$1 & $2 = SBT.(textij); Q18: for j be Nat st j in Seg 4 ex xi being Element of (8-tuples_on BOOLEAN) st Pi[j,xi] proof let j be Nat; assume j in Seg 4; then j in dom(textk) by Q13,FINSEQ_1:def 3; then (textk).j in rng (textk) by FUNCT_1:3; then reconsider textkj = (textk).j as Element of 8-tuples_on BOOLEAN; SBT.(textkj) = SBT.(textkj); hence thesis; end; consider zk be FinSequence of (8-tuples_on BOOLEAN) such that Q22: dom zk = Seg 4 & for j be Nat st j in Seg 4 holds Pi[j,zk.j] from FINSEQ_1:sch 5(Q18); Q23: len zk = 4 by Q22,FINSEQ_1:def 3; reconsider zk as Element of (8-tuples_on BOOLEAN)* by FINSEQ_1:def 11; zk in 4-tuples_on (8-tuples_on BOOLEAN) by Q23; then reconsider zk as Element of 4-tuples_on (8-tuples_on BOOLEAN); for j be Nat st j in Seg 4 holds ex textij be Element of 8-tuples_on BOOLEAN st textij = (textk).j & zk.j = SBT.(textij) by Q22; hence thesis; end; consider z be FinSequence of 4-tuples_on (8-tuples_on BOOLEAN) such that Q2: dom z = Seg 4 & for i be Nat st i in Seg 4 holds P[i,z.i] from FINSEQ_1:sch 5(Q1); Q3: len z = 4 by Q2,FINSEQ_1:def 3; reconsider z as Element of (4-tuples_on (8-tuples_on BOOLEAN))* by FINSEQ_1:def 11; z in 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) by Q3; then reconsider z as Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); take z; for i,j be Nat st i in Seg 4 & j in Seg 4 holds ex textij be Element of 8-tuples_on BOOLEAN st textij = (text.i).j & (z.i).j = SBT.(textij) proof let i,j be Nat; assume Q4: i in Seg 4 & j in Seg 4; then ex zi be Element of (4-tuples_on (8-tuples_on BOOLEAN)) st z.i = zi & for j be Nat st j in Seg 4 holds ex textij be Element of 8-tuples_on BOOLEAN st textij = (text.i).j & zi.j = SBT.(textij) by Q2; hence ex textij be Element of 8-tuples_on BOOLEAN st textij = (text.i).j & (z.i).j = SBT.(textij) by Q4; end; hence thesis; end; consider I be Function of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) such that A2: for x being Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds P0[x,I.x] from FUNCT_2:sch 3(A1); take I; thus thesis by A2; end; uniqueness proof let F1,F2 be Function of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); assume A1: for text be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds for i,j be Nat st i in Seg 4 & j in Seg 4 holds ex textij be Element of 8-tuples_on BOOLEAN st textij = (text.i).j & ((F1.text).i).j = SBT.(textij); assume A2: for text be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds for i,j be Nat st i in Seg 4 & j in Seg 4 holds ex textij be Element of 8-tuples_on BOOLEAN st textij = (text.i).j & ((F2.text).i).j = SBT.(textij); now let text be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); now let i,j be Nat; assume A3: i in Seg 4 & j in Seg 4; then A4: ex textij be Element of 8-tuples_on BOOLEAN st textij = (text.i).j & ((F1.text).i).j = SBT.(textij) by A1; A5: ex textij be Element of 8-tuples_on BOOLEAN st textij = (text.i).j & ((F2.text).i).j = SBT.(textij) by A3,A2; thus ((F1.text).i).j = ((F2.text).i).j by A4,A5; end; hence F1.text = F2.text by LM01; end; hence F1 = F2 by FUNCT_2:63; end; end; definition let SBT; func InvSubBytes(SBT) -> Function of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) means :DefInvSubBytes: for input be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds for i,j be Nat st i in Seg 4 & j in Seg 4 holds ex inputij be Element of 8-tuples_on BOOLEAN st inputij = (input.i).j & ((it.input).i).j = (SBT").(inputij); existence proof defpred P0[Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN))] means for i,j be Nat st i in Seg 4 & j in Seg 4 holds ex inputij be Element of 8-tuples_on BOOLEAN st inputij = ($1.i).j & ($2.i).j = (SBT").(inputij); A1: for text being Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) ex z be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st P0[text,z] proof let text be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); text in 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); then Q01: ex s be Element of (4-tuples_on (8-tuples_on BOOLEAN))* st text = s & len s = 4; defpred P[Nat,set] means ex zk be Element of (4-tuples_on (8-tuples_on BOOLEAN)) st $2 = zk & for j be Nat st j in Seg 4 holds ex textij be Element of 8-tuples_on BOOLEAN st textij = (text.$1).j & zk.j = (SBT").(textij); Q1: for k be Nat st k in Seg 4 ex zk being Element of (4-tuples_on (8-tuples_on BOOLEAN)) st P[k,zk] proof let k be Nat; assume k in Seg 4; then k in dom text by Q01,FINSEQ_1:def 3; then text.k in rng text by FUNCT_1:3; then text.k in 4-tuples_on (8-tuples_on BOOLEAN); then Q13: ex s be Element of (8-tuples_on BOOLEAN)* st text.k = s & len s = 4; then reconsider textk = text.k as Element of (8-tuples_on BOOLEAN)*; defpred Pi[Nat,set] means ex textij be Element of 8-tuples_on BOOLEAN st textij = (textk).$1 & $2 = (SBT").(textij); Q18: for j be Nat st j in Seg 4 ex xi being Element of (8-tuples_on BOOLEAN) st Pi[j,xi] proof let j be Nat; assume j in Seg 4; then j in dom(textk) by Q13,FINSEQ_1:def 3; then (textk).j in rng (textk) by FUNCT_1:3; then reconsider textkj = (textk).j as Element of 8-tuples_on BOOLEAN; (SBT").(textkj) = (SBT").(textkj); hence thesis; end; consider zk be FinSequence of (8-tuples_on BOOLEAN) such that Q22: dom zk = Seg 4 & for j be Nat st j in Seg 4 holds Pi[j,zk.j ] from FINSEQ_1:sch 5(Q18); Q23: len zk = 4 by Q22,FINSEQ_1:def 3; reconsider zk as Element of (8-tuples_on BOOLEAN)* by FINSEQ_1:def 11; zk in 4-tuples_on (8-tuples_on BOOLEAN) by Q23; then reconsider zk as Element of 4-tuples_on (8-tuples_on BOOLEAN); for j be Nat st j in Seg 4 holds ex textij be Element of 8-tuples_on BOOLEAN st textij = (textk).j & zk.j = (SBT").(textij) by Q22; hence thesis; end; consider z be FinSequence of 4-tuples_on (8-tuples_on BOOLEAN) such that Q2: dom z = Seg 4 & for i be Nat st i in Seg 4 holds P[i,z.i] from FINSEQ_1:sch 5(Q1); Q3: len z = 4 by Q2,FINSEQ_1:def 3; reconsider z as Element of (4-tuples_on (8-tuples_on BOOLEAN))* by FINSEQ_1:def 11; z in 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) by Q3; then reconsider z as Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); take z; for i,j be Nat st i in Seg 4 & j in Seg 4 holds ex textij be Element of 8-tuples_on BOOLEAN st textij = (text.i).j & (z.i).j = (SBT").(textij) proof let i,j be Nat; assume Q4: i in Seg 4 & j in Seg 4; then ex zi be Element of (4-tuples_on (8-tuples_on BOOLEAN)) st z.i = zi & for j be Nat st j in Seg 4 holds ex textij be Element of 8-tuples_on BOOLEAN st textij = (text.i).j & zi.j = (SBT").(textij) by Q2; hence ex textij be Element of 8-tuples_on BOOLEAN st textij = (text.i).j & (z.i).j = (SBT").(textij) by Q4; end; hence thesis; end; consider I be Function of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) such that A2: for x being Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds P0[x,I.x] from FUNCT_2:sch 3(A1); take I; thus thesis by A2; end; uniqueness proof let F1,F2 be Function of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); assume A1: for text be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds for i,j be Nat st i in Seg 4 & j in Seg 4 holds ex textij be Element of 8-tuples_on BOOLEAN st textij = (text.i).j & ((F1.text).i).j = (SBT").(textij); assume A2: for text be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds for i,j be Nat st i in Seg 4 & j in Seg 4 holds ex textij be Element of 8-tuples_on BOOLEAN st textij = (text.i).j & ((F2.text).i).j = (SBT").(textij); now let text be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); now let i,j be Nat; assume A3: i in Seg 4 & j in Seg 4; then A4: ex textij be Element of 8-tuples_on BOOLEAN st textij = (text.i).j & ((F1.text).i).j = (SBT").(textij) by A1; A5: ex textij be Element of 8-tuples_on BOOLEAN st textij = (text.i).j & ((F2.text).i).j = (SBT").(textij) by A3,A2; thus ((F1.text).i).j = ((F2.text).i).j by A4,A5; end; hence F1.text = F2.text by LM01; end; hence F1 = F2 by FUNCT_2:63; end; end; INV07A: for input be Element of 8-tuples_on BOOLEAN holds (SBT").(SBT.(input)) = input proof let input be Element of 8-tuples_on BOOLEAN; thus (SBT").(SBT.(input)) = ((SBT")*SBT).input by FUNCT_2:15 .= (id (8-tuples_on BOOLEAN)).input by FUNCT_2:61 .= input; end; INV08A: for input be Element of 8-tuples_on BOOLEAN holds SBT.((SBT").(input)) = input proof let input be Element of 8-tuples_on BOOLEAN; thus SBT.((SBT").(input)) = (SBT*(SBT")).input by FUNCT_2:15 .= (id (8-tuples_on BOOLEAN)).input by FUNCT_2:61 .= input; end; theorem INV07: for input be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds (InvSubBytes(SBT)).((SubBytes(SBT)).input) = input proof let input be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); now let i,j be Nat; assume A3: i in Seg 4 & j in Seg 4; then consider outputij be Element of 8-tuples_on BOOLEAN such that A4: outputij = (((SubBytes(SBT)).input).i).j & (((InvSubBytes(SBT)).((SubBytes(SBT)).input)).i).j = (SBT").(outputij) by DefInvSubBytes; consider inputij be Element of 8-tuples_on BOOLEAN such that A5: inputij = (input.i).j & (((SubBytes(SBT)).input).i).j = SBT.(inputij) by DefSubBytes,A3; thus (((InvSubBytes(SBT)).((SubBytes(SBT)).input)).i).j = (input.i).j by A4,A5,INV07A; end; hence (InvSubBytes(SBT)).((SubBytes(SBT)).input) = input by LM01; end; theorem INV08: for output be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds (SubBytes(SBT)).((InvSubBytes(SBT)).output) = output proof let input be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); now let i,j be Nat; assume A3: i in Seg 4 & j in Seg 4; then consider outputij be Element of 8-tuples_on BOOLEAN such that A4: outputij = (((InvSubBytes(SBT)).input).i).j & (((SubBytes(SBT)).((InvSubBytes(SBT)).input)).i).j = SBT.(outputij) by DefSubBytes; consider inputij be Element of 8-tuples_on BOOLEAN such that A5: inputij = (input.i).j & (((InvSubBytes(SBT)).input).i).j = (SBT").(inputij) by DefInvSubBytes,A3; thus (((SubBytes(SBT)).((InvSubBytes(SBT)).input)).i).j = (input.i).j by A4,A5,INV08A; end; hence (SubBytes(SBT)).((InvSubBytes(SBT)).input) = input by LM01; end; theorem SubBytes(SBT) is one-to-one & SubBytes(SBT) is onto & InvSubBytes(SBT) is one-to-one & InvSubBytes(SBT) is onto & InvSubBytes(SBT) = (SubBytes(SBT))" & SubBytes(SBT) = (InvSubBytes(SBT))" proof set f = SubBytes(SBT); set g = InvSubBytes(SBT); P1: for x be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds g.(f.x) = x by INV07; P2: for y be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds f.(g.y) = y by INV08; thus f is one-to-one & f is onto & g is one-to-one & g is onto & g = f" & f = g" by INV00,P1,P2; end; begin :: ShiftRows definition func ShiftRows -> Function of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) means :DefShiftRows: for input be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds (for i be Nat st i in Seg 4 holds ex xi be Element of 4-tuples_on (8-tuples_on BOOLEAN) st xi = input.i & (it.input).i = Op-Shift(xi,5-i)); existence proof defpred P0[Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN))] means for i be Nat st i in Seg 4 holds ex xi be Element of 4-tuples_on (8-tuples_on BOOLEAN) st xi = $1.i & $2.i = Op-Shift(xi,5-i); A1: for x being Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) ex z be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st P0[x,z] proof let x be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); x in 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); then Q01: ex s be Element of (4-tuples_on (8-tuples_on BOOLEAN))* st x = s & len s = 4; defpred P[Nat,set] means ex xk be Element of 4-tuples_on (8-tuples_on BOOLEAN) st xk = x.$1 & $2 = Op-Shift(xk,5-$1); Q1: for k be Nat st k in Seg 4 ex zk being Element of (4-tuples_on (8-tuples_on BOOLEAN)) st P[k,zk] proof let k be Nat; assume k in Seg 4; then k in dom x by Q01,FINSEQ_1:def 3; then Q11: x.k in rng x by FUNCT_1:3; then x.k in 4-tuples_on (8-tuples_on BOOLEAN); then Q13: ex s be Element of (8-tuples_on BOOLEAN)* st x.k = s & len s = 4; then reconsider xk = x.k as Element of (8-tuples_on BOOLEAN)*; reconsider xk1 = xk as Element of 4-tuples_on (8-tuples_on BOOLEAN) by Q11; reconsider zk = Op-Shift(xk,5-k) as FinSequence of (8-tuples_on BOOLEAN); Q15: len zk = 4 by Q13,DESCIP_1:def 3; reconsider zk as Element of (8-tuples_on BOOLEAN)* by FINSEQ_1:def 11; zk in 4-tuples_on (8-tuples_on BOOLEAN) by Q15; then reconsider zk as Element of 4-tuples_on (8-tuples_on BOOLEAN); ex xk be Element of 4-tuples_on (8-tuples_on BOOLEAN) st xk = x.k & zk = Op-Shift(xk1,5-k); hence thesis; end; consider z be FinSequence of 4-tuples_on (8-tuples_on BOOLEAN) such that Q2: dom z = Seg 4 & for i be Nat st i in Seg 4 holds P[i,z.i] from FINSEQ_1:sch 5(Q1); Q3: len z = 4 by Q2,FINSEQ_1:def 3; reconsider z as Element of (4-tuples_on (8-tuples_on BOOLEAN))* by FINSEQ_1:def 11; z in 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) by Q3; hence thesis by Q2; end; consider I be Function of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) such that A2: for x being Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds P0[x,I.x] from FUNCT_2:sch 3(A1); take I; thus thesis by A2; end; uniqueness proof let H1,H2 be Function of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); assume A1: for input be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds (for i be Nat st i in Seg 4 holds ex xi be Element of 4-tuples_on (8-tuples_on BOOLEAN) st xi = input.i & (H1.input).i = Op-Shift(xi,5-i)); assume A2: for input be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds (for i be Nat st i in Seg 4 holds ex xi be Element of 4-tuples_on (8-tuples_on BOOLEAN) st xi = input.i & (H2.input).i = Op-Shift(xi,5-i)); now let input be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); H1.input in 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); then P3: ex s be Element of (4-tuples_on(8-tuples_on BOOLEAN))* st H1.input = s & len s = 4; H2.input in 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); then P4: ex s be Element of (4-tuples_on(8-tuples_on BOOLEAN))* st H2.input = s & len s = 4; now let i be Nat; assume 1 <= i & i <= len (H1.input); then XX2: i in Seg 4 by P3; then XX3: ex xi be Element of 4-tuples_on (8-tuples_on BOOLEAN) st xi = input.i & (H1.input).i = Op-Shift(xi,5-i) by A1; XX4: ex xi be Element of 4-tuples_on (8-tuples_on BOOLEAN) st xi = input.i & (H2.input).i = Op-Shift(xi,5-i) by A2,XX2; thus (H1.input).i = (H2.input).i by XX3,XX4; end; hence H1.input = H2.input by P3,P4,FINSEQ_1:14; end; hence H1 = H2 by FUNCT_2:63; end; end; definition func InvShiftRows -> Function of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) means :DefInvShiftRows: for input be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds (for i be Nat st i in Seg 4 holds ex xi be Element of 4-tuples_on (8-tuples_on BOOLEAN) st xi = input.i & (it.input).i = Op-Shift(xi,i-1)); existence proof defpred P0[Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN))] means for i be Nat st i in Seg 4 holds ex xi be Element of 4-tuples_on (8-tuples_on BOOLEAN) st xi = $1.i & $2.i = Op-Shift(xi,i-1); A1: for x being Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) ex z be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st P0[x,z] proof let x be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); x in 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); then Q01: ex s be Element of (4-tuples_on (8-tuples_on BOOLEAN))* st x = s & len s = 4; defpred P[Nat,set] means ex xk be Element of 4-tuples_on (8-tuples_on BOOLEAN) st xk = x.$1 & $2 = Op-Shift(xk,$1-1); Q1: for k be Nat st k in Seg 4 ex zk being Element of (4-tuples_on (8-tuples_on BOOLEAN)) st P[k,zk] proof let k be Nat; assume k in Seg 4; then k in dom x by Q01,FINSEQ_1:def 3; then Q11: x.k in rng x by FUNCT_1:3; then x.k in 4-tuples_on (8-tuples_on BOOLEAN); then Q13: ex s be Element of (8-tuples_on BOOLEAN)* st x.k = s & len s = 4; then reconsider xk = x.k as Element of (8-tuples_on BOOLEAN)*; reconsider xk1 = xk as Element of 4-tuples_on (8-tuples_on BOOLEAN) by Q11; reconsider zk = Op-Shift(xk,k-1) as FinSequence of (8-tuples_on BOOLEAN); Q15: len zk = 4 by Q13,DESCIP_1:def 3; reconsider zk as Element of (8-tuples_on BOOLEAN)* by FINSEQ_1:def 11; zk in 4-tuples_on (8-tuples_on BOOLEAN) by Q15; then reconsider zk as Element of 4-tuples_on (8-tuples_on BOOLEAN); ex xk be Element of 4-tuples_on (8-tuples_on BOOLEAN) st xk = x.k & zk = Op-Shift(xk1,k-1); hence thesis; end; consider z be FinSequence of 4-tuples_on (8-tuples_on BOOLEAN) such that Q2: dom z = Seg 4 & for i be Nat st i in Seg 4 holds P[i,z.i] from FINSEQ_1:sch 5(Q1); Q3: len z = 4 by Q2,FINSEQ_1:def 3; reconsider z as Element of (4-tuples_on (8-tuples_on BOOLEAN))* by FINSEQ_1:def 11; z in 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) by Q3; hence thesis by Q2; end; consider I be Function of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) such that A2: for x being Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds P0[x,I.x] from FUNCT_2:sch 3(A1); take I; thus thesis by A2; end; uniqueness proof let H1,H2 be Function of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); assume A1: for input be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds (for i be Nat st i in Seg 4 holds ex xi be Element of 4-tuples_on (8-tuples_on BOOLEAN) st xi = input.i & (H1.input).i = Op-Shift(xi,i-1)); assume A2: for input be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds (for i be Nat st i in Seg 4 holds ex xi be Element of 4-tuples_on (8-tuples_on BOOLEAN) st xi = input.i & (H2.input).i = Op-Shift(xi,i-1)); now let input be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); H1.input in 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); then P3: ex s be Element of (4-tuples_on(8-tuples_on BOOLEAN))* st H1.input = s & len s = 4; H2.input in 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); then P4: ex s be Element of (4-tuples_on(8-tuples_on BOOLEAN))* st H2.input = s & len s = 4; now let i be Nat; assume 1 <= i & i <= len (H1.input); then XX2: i in Seg 4 by P3; then XX3: ex xi be Element of 4-tuples_on (8-tuples_on BOOLEAN) st xi = input.i & (H1.input).i = Op-Shift(xi,i-1) by A1; XX4: ex xi be Element of 4-tuples_on (8-tuples_on BOOLEAN) st xi = input.i & (H2.input).i = Op-Shift(xi,i-1) by A2,XX2; thus (H1.input).i = (H2.input).i by XX3,XX4; end; hence H1.input = H2.input by P3,P4,FINSEQ_1:14; end; hence H1 = H2 by FUNCT_2:63; end; end; theorem INV04: for input be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds InvShiftRows.(ShiftRows.input) = input proof let input be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); InvShiftRows.(ShiftRows.input) in 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); then P3: ex s be Element of (4-tuples_on(8-tuples_on BOOLEAN))* st InvShiftRows.(ShiftRows.input) = s & len s = 4; input in 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); then P4: ex s be Element of (4-tuples_on(8-tuples_on BOOLEAN))* st input = s & len s = 4; now let i be Nat; assume 1 <= i & i <= len (InvShiftRows.(ShiftRows.input)); then XX2: i in Seg 4 by P3; then consider xi be Element of 4-tuples_on (8-tuples_on BOOLEAN) such that XX3: xi = input.i & (ShiftRows.input).i = Op-Shift(xi,5-i) by DefShiftRows; xi in 4-tuples_on (8-tuples_on BOOLEAN); then YY1: ex s be Element of (8-tuples_on BOOLEAN)* st xi = s & len s = 4; consider yi be Element of 4-tuples_on (8-tuples_on BOOLEAN) such that XX4: yi = (ShiftRows.input).i & (InvShiftRows.(ShiftRows.input)).i = Op-Shift(yi,i-1) by DefInvShiftRows,XX2; thus (InvShiftRows.(ShiftRows.input)).i = Op-Shift(xi,5-i+(i-1)) by XX3,XX4,DESCIP_1:10,YY1 .= input.i by DESCIP_1:12,YY1,XX3; end; hence (InvShiftRows.(ShiftRows.input)) = input by P3,P4,FINSEQ_1:14; end; theorem INV05: for output be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds ShiftRows.(InvShiftRows.output) = output proof let output be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); ShiftRows.(InvShiftRows.output) in 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); then P3: ex s be Element of (4-tuples_on(8-tuples_on BOOLEAN))* st ShiftRows.(InvShiftRows.output) = s & len s = 4; output in 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); then P4: ex s be Element of (4-tuples_on(8-tuples_on BOOLEAN))* st output = s & len s = 4; now let i be Nat; assume 1 <= i & i <= len (ShiftRows.(InvShiftRows.output)); then XX2: i in Seg 4 by P3; then consider xi be Element of 4-tuples_on (8-tuples_on BOOLEAN) such that XX3: xi = output.i & (InvShiftRows.output).i = Op-Shift(xi,i-1) by DefInvShiftRows; xi in 4-tuples_on (8-tuples_on BOOLEAN); then YY1: ex s be Element of (8-tuples_on BOOLEAN)* st xi = s & len s = 4; consider yi be Element of 4-tuples_on (8-tuples_on BOOLEAN) such that XX4: yi = (InvShiftRows.output).i & (ShiftRows.(InvShiftRows.output)).i = Op-Shift(yi,5-i) by DefShiftRows,XX2; thus (ShiftRows.(InvShiftRows.output)).i = Op-Shift(xi,i-1+(5-i)) by XX3,XX4,DESCIP_1:10,YY1 .= output.i by DESCIP_1:12,YY1,XX3; end; hence (ShiftRows.(InvShiftRows.output)) = output by P3,P4,FINSEQ_1:14; end; theorem ShiftRows is one-to-one & ShiftRows is onto & InvShiftRows is one-to-one & InvShiftRows is onto & InvShiftRows = (ShiftRows)" & ShiftRows = (InvShiftRows)" by INV00,INV04,INV05; begin :: AddRoundKey definition func AddRoundKey -> Function of [:4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)):], 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) means :DefAddRoundKey: for text, key be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds for i,j be Nat st i in Seg 4 & j in Seg 4 holds ex textij,keyij be Element of 8-tuples_on BOOLEAN st textij = (text.i).j & keyij = (key.i).j & ((it.(text,key)).i).j = Op-XOR(textij,keyij); existence proof defpred P0[Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN))] means for i,j be Nat st i in Seg 4 & j in Seg 4 holds ex textij,keyij be Element of 8-tuples_on BOOLEAN st textij = ($1.i).j & keyij = ($2.i).j & ($3.i).j = Op-XOR(textij,keyij); A1: for text,key being Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) ex z be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st P0[text,key,z] proof let text, key be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); text in 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); then Q01: ex s be Element of (4-tuples_on (8-tuples_on BOOLEAN))* st text = s & len s = 4; key in 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); then Q02: ex s be Element of (4-tuples_on (8-tuples_on BOOLEAN))* st key = s & len s = 4; defpred P[Nat,set] means ex zk be Element of (4-tuples_on (8-tuples_on BOOLEAN)) st $2 = zk & for j be Nat st j in Seg 4 holds ex textij,keyij be Element of 8-tuples_on BOOLEAN st textij = (text.$1).j & keyij = (key.$1).j & zk.j = Op-XOR(textij,keyij); Q1: for k be Nat st k in Seg 4 ex zk being Element of (4-tuples_on (8-tuples_on BOOLEAN)) st P[k,zk] proof let k be Nat; assume Q11: k in Seg 4; then k in dom text by Q01,FINSEQ_1:def 3; then text.k in rng text by FUNCT_1:3; then text.k in 4-tuples_on (8-tuples_on BOOLEAN); then Q13: ex s be Element of (8-tuples_on BOOLEAN)* st text.k = s & len s = 4; then reconsider textk = text.k as Element of (8-tuples_on BOOLEAN)*; k in dom(key) by Q02,FINSEQ_1:def 3,Q11; then key.k in rng key by FUNCT_1:3; then key.k in 4-tuples_on (8-tuples_on BOOLEAN); then Q16: ex s be Element of (8-tuples_on BOOLEAN)* st key.k = s & len s = 4; then reconsider keyk = key.k as Element of (8-tuples_on BOOLEAN)*; defpred Pi[Nat,set] means ex textij,keyij be Element of 8-tuples_on BOOLEAN st textij = (textk).$1 & keyij = (keyk).$1 & $2 = Op-XOR(textij,keyij); Q18: for j be Nat st j in Seg 4 ex xi being Element of (8-tuples_on BOOLEAN) st Pi[j,xi] proof let j be Nat; assume Q19: j in Seg 4; then j in dom(textk) by Q13,FINSEQ_1:def 3; then (textk).j in rng (textk) by FUNCT_1:3; then reconsider textkj = (textk).j as Element of 8-tuples_on BOOLEAN; j in dom(keyk) by Q16,FINSEQ_1:def 3,Q19; then (keyk).j in rng (keyk) by FUNCT_1:3; then reconsider keykj = (key.k).j as Element of 8-tuples_on BOOLEAN; Op-XOR(textkj,keykj) = Op-XOR(textkj,keykj); hence thesis; end; consider zk be FinSequence of (8-tuples_on BOOLEAN) such that Q22: dom zk = Seg 4 & for j be Nat st j in Seg 4 holds Pi[j,zk.j] from FINSEQ_1:sch 5(Q18); Q23: len zk = 4 by Q22,FINSEQ_1:def 3; reconsider zk as Element of (8-tuples_on BOOLEAN)* by FINSEQ_1:def 11; zk in 4-tuples_on (8-tuples_on BOOLEAN) by Q23; then reconsider zk as Element of 4-tuples_on (8-tuples_on BOOLEAN); for j be Nat st j in Seg 4 holds ex textij,keyij be Element of 8-tuples_on BOOLEAN st textij = (textk).j & keyij = (keyk).j & zk.j = Op-XOR(textij,keyij) by Q22; hence thesis; end; consider z be FinSequence of 4-tuples_on (8-tuples_on BOOLEAN) such that Q2: dom z = Seg 4 & for i be Nat st i in Seg 4 holds P[i,z.i] from FINSEQ_1:sch 5(Q1); Q3: len z = 4 by Q2,FINSEQ_1:def 3; reconsider z as Element of (4-tuples_on (8-tuples_on BOOLEAN))* by FINSEQ_1:def 11; z in 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) by Q3; then reconsider z as Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); take z; for i,j be Nat st i in Seg 4 & j in Seg 4 holds ex textij,keyij be Element of 8-tuples_on BOOLEAN st textij = (text.i).j & keyij = (key.i).j & (z.i).j = Op-XOR(textij,keyij) proof let i,j be Nat; assume Q4: i in Seg 4 & j in Seg 4; then ex zi be Element of (4-tuples_on (8-tuples_on BOOLEAN)) st z.i = zi & for j be Nat st j in Seg 4 holds ex textij,keyij be Element of 8-tuples_on BOOLEAN st textij = (text.i).j & keyij = (key.i).j & zi.j = Op-XOR(textij,keyij) by Q2; hence ex textij,keyij be Element of 8-tuples_on BOOLEAN st textij = (text.i).j & keyij = (key.i).j & (z.i).j = Op-XOR(textij,keyij) by Q4; end; hence thesis; end; consider I be Function of [:4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)):], 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) such that A2: for x,y being Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds P0[x,y,I.(x,y)] from BINOP_1:sch 3(A1); take I; thus thesis by A2; end; uniqueness proof let F1,F2 be Function of [:4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)):], 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); assume A1: for text,key be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds for i,j be Nat st i in Seg 4 & j in Seg 4 holds ex textij,keyij be Element of 8-tuples_on BOOLEAN st textij = (text.i).j & keyij = (key.i).j & ((F1.(text,key)).i).j = Op-XOR(textij,keyij); assume A2: for text,key be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds for i,j be Nat st i in Seg 4 & j in Seg 4 holds ex textij,keyij be Element of 8-tuples_on BOOLEAN st textij = (text.i).j & keyij = (key.i).j & ((F2.(text,key)).i).j = Op-XOR(textij,keyij); now let text,key be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); now let i,j be Nat; assume A3: i in Seg 4 & j in Seg 4; then A4: ex textij,keyij be Element of 8-tuples_on BOOLEAN st textij = (text.i).j & keyij = (key.i).j & ((F1.(text,key)).i).j = Op-XOR(textij,keyij) by A1; A5: ex textij,keyij be Element of 8-tuples_on BOOLEAN st textij = (text.i).j & keyij = (key.i).j & ((F2.(text,key)).i).j = Op-XOR(textij,keyij) by A3,A2; thus ((F1.(text,key)).i).j = ((F2.(text,key)).i).j by A4,A5; end; hence F1.(text,key) = F2.(text,key) by LM01; end; hence F1 = F2 by BINOP_1:2; end; end; begin :: Key Expansion definition let SBT; let x be Element of 4-tuples_on (8-tuples_on BOOLEAN); func SubWord(SBT,x) -> Element of 4-tuples_on (8-tuples_on BOOLEAN) means for i be Element of Seg 4 holds it.i = SBT.(x.i); existence proof defpred P[Nat,set] means ex xi be Element of 8-tuples_on BOOLEAN st xi = x.$1 & $2 = SBT.(xi); P1: for k be Nat st k in Seg 4 ex z being Element of 8-tuples_on BOOLEAN st P[k,z] proof let k be Nat; assume AS: k in Seg 4; x in 4-tuples_on (8-tuples_on BOOLEAN); then ex s be Element of (8-tuples_on BOOLEAN)* st x = s & len s = 4; then k in dom x by FINSEQ_1:def 3,AS; then x.k in rng x by FUNCT_1:3; then reconsider xk = x.k as Element of 8-tuples_on BOOLEAN; SBT.(xk) is Element of 8-tuples_on BOOLEAN; hence thesis; end; consider p being FinSequence of 8-tuples_on BOOLEAN such that P3: dom p = Seg 4 & for k be Nat st k in Seg 4 holds P[k,p.k] from FINSEQ_1:sch 5(P1); reconsider p as Element of (8-tuples_on BOOLEAN)* by FINSEQ_1:def 11; len p = 4 by P3,FINSEQ_1:def 3; then p in 4-tuples_on (8-tuples_on BOOLEAN); then reconsider p as Element of 4-tuples_on (8-tuples_on BOOLEAN); take p; now let i be Element of Seg 4; ex xi be Element of 8-tuples_on BOOLEAN st xi = x.i & p.i = SBT.(xi) by P3; hence p.i = SBT.(x.i); end; hence thesis; end; uniqueness proof let H1,H2 be Element of 4-tuples_on (8-tuples_on BOOLEAN); assume A1: for i be Element of Seg 4 holds H1.i = SBT.(x.i); assume A2: for i be Element of Seg 4 holds H2.i = SBT.(x.i); H1 in 4-tuples_on (8-tuples_on BOOLEAN); then P1: ex s be Element of (8-tuples_on BOOLEAN)* st H1 = s & len s = 4; H2 in 4-tuples_on (8-tuples_on BOOLEAN); then P2: ex s be Element of (8-tuples_on BOOLEAN)* st H2 = s & len s = 4; now let i be Nat; assume 1 <= i & i <= len H1; then i in Seg 4 by P1; then reconsider j = i as Element of Seg 4; thus H1.i = (SBT).(x.j) by A1 .= H2.i by A2; end; hence H1 = H2 by P1,P2,FINSEQ_1:14; end; end; definition let x be Element of 4-tuples_on (8-tuples_on BOOLEAN); func RotWord(x) -> Element of 4-tuples_on (8-tuples_on BOOLEAN) equals Op-LeftShift(x); correctness by DESCIP_1:6; end; definition let n,m be non zero Element of NAT; let s,t be Element of m-tuples_on (n-tuples_on BOOLEAN); func Op-WXOR(s,t) -> Element of m-tuples_on (n-tuples_on BOOLEAN) means for i be Element of Seg m holds it.i = Op-XOR(s.i,t.i); existence proof defpred P[Nat,set] means ex si,ti be Element of (n-tuples_on BOOLEAN) st si = s.$1 & ti = t.$1 & $2 = Op-XOR(si,ti); P1: for k be Nat st k in Seg m ex z being Element of n-tuples_on BOOLEAN st P[k,z] proof let k be Nat; assume AS: k in Seg m; s in m-tuples_on (n-tuples_on BOOLEAN); then ex v be Element of (n-tuples_on BOOLEAN)* st s = v & len v = m; then k in dom s by FINSEQ_1:def 3,AS; then s.k in rng s by FUNCT_1:3; then reconsider sk = s.k as Element of n-tuples_on BOOLEAN; t in m-tuples_on (n-tuples_on BOOLEAN); then ex v be Element of (n-tuples_on BOOLEAN)* st t = v & len v = m; then k in dom t by FINSEQ_1:def 3,AS; then t.k in rng t by FUNCT_1:3; then reconsider tk = t.k as Element of n-tuples_on BOOLEAN; Op-XOR(sk,tk) is Element of n-tuples_on BOOLEAN; hence thesis; end; consider p being FinSequence of n-tuples_on BOOLEAN such that P3: dom p = Seg m & for k be Nat st k in Seg m holds P[k,p.k] from FINSEQ_1:sch 5(P1); P4: len p = m by P3,FINSEQ_1:def 3; p in (n-tuples_on BOOLEAN)* by FINSEQ_1:def 11; then p in m-tuples_on (n-tuples_on BOOLEAN) by P4; then reconsider p as Element of m-tuples_on (n-tuples_on BOOLEAN); take p; now let i be Element of Seg m; ex si,ti be Element of n-tuples_on BOOLEAN st si = s.i & ti = t.i & p.i = Op-XOR(si,ti) by P3; hence p.i = Op-XOR(s.i,t.i); end; hence thesis; end; uniqueness proof let H1,H2 be Element of m-tuples_on (n-tuples_on BOOLEAN); assume A1: for i be Element of Seg m holds H1.i = Op-XOR(s.i,t.i); assume A2: for i be Element of Seg m holds H2.i = Op-XOR(s.i,t.i); H1 in m-tuples_on (n-tuples_on BOOLEAN); then P1: ex v be Element of (n-tuples_on BOOLEAN)* st H1 = v & len v = m; H2 in m-tuples_on (n-tuples_on BOOLEAN); then P2: ex v be Element of (n-tuples_on BOOLEAN)* st H2 = v & len v = m; now let i be Nat; assume 1 <= i & i <= len H1; then i in Seg m by P1; then reconsider j = i as Element of Seg m; thus H1.i = Op-XOR(s.j,t.j) by A1 .= H2.i by A2; end; hence H1 = H2 by P1,P2,FINSEQ_1:14; end; end; definition func Rcon -> Element of 10-tuples_on (4-tuples_on (8-tuples_on BOOLEAN)) means it.1 = <* <*0,0,0,0*>^<*0,0,0,1*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *> & it.2 = <* <*0,0,0,0*>^<*0,0,1,0*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *> & it.3 = <* <*0,0,0,0*>^<*0,1,0,0*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *> & it.4 = <* <*0,0,0,0*>^<*1,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *> & it.5 = <* <*0,0,0,1*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *> & it.6 = <* <*0,0,1,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *> & it.7 = <* <*0,1,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *> & it.8 = <* <*1,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *> & it.9 = <* <*0,0,0,1*>^<*1,0,1,1*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *> & it.10 = <* <*0,0,1,1*>^<*0,1,1,0*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *>; existence proof X0: 0 in BOOLEAN by TARSKI:def 2,MARGREL1:def 11; X1: 1 in BOOLEAN by TARSKI:def 2,MARGREL1:def 11; P1: <*0,0,0,0*> is Element of (4-tuples_on BOOLEAN) by LMGSEQ4,X0; P2: <*0,0,0,1*> is Element of (4-tuples_on BOOLEAN) by LMGSEQ4,X0,X1; P3: <*0,0,1,0*> is Element of (4-tuples_on BOOLEAN) by LMGSEQ4,X0,X1; P4: <*0,1,0,0*> is Element of (4-tuples_on BOOLEAN) by LMGSEQ4,X0,X1; P5: <*1,0,0,0*> is Element of (4-tuples_on BOOLEAN) by LMGSEQ4,X0,X1; R1: <*1,0,1,1*> is Element of (4-tuples_on BOOLEAN) by LMGSEQ4,X0,X1; R2: <*0,0,1,1*> is Element of (4-tuples_on BOOLEAN) by LMGSEQ4,X0,X1; R3: <*0,1,1,0*> is Element of (4-tuples_on BOOLEAN) by LMGSEQ4,X0,X1; reconsider PP6 = <* <*0,0,0,0*>^<*0,0,0,1*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *> as Element of 4-tuples_on (8-tuples_on BOOLEAN) by P1,P2,LMGSEQ16; reconsider PP7 = <* <*0,0,0,0*>^<*0,0,1,0*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *> as Element of 4-tuples_on (8-tuples_on BOOLEAN) by P1,P3,LMGSEQ16; reconsider PP8 = <* <*0,0,0,0*>^<*0,1,0,0*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *> as Element of 4-tuples_on (8-tuples_on BOOLEAN) by P1,P4,LMGSEQ16; reconsider PP9 = <* <*0,0,0,0*>^<*1,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *> as Element of 4-tuples_on (8-tuples_on BOOLEAN) by P1,P5,LMGSEQ16; reconsider PP10 = <* <*0,0,0,1*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *> as Element of 4-tuples_on (8-tuples_on BOOLEAN) by P1,P2,LMGSEQ16; reconsider PP11 = <* <*0,0,1,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *> as Element of 4-tuples_on (8-tuples_on BOOLEAN) by P1,P3,LMGSEQ16; reconsider PP12 = <* <*0,1,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *> as Element of 4-tuples_on (8-tuples_on BOOLEAN) by P1,P4,LMGSEQ16; reconsider PP13 = <* <*1,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *> as Element of 4-tuples_on (8-tuples_on BOOLEAN) by P1,P5,LMGSEQ16; reconsider PP14 = <* <*0,0,0,1*>^<*1,0,1,1*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *> as Element of 4-tuples_on (8-tuples_on BOOLEAN) by P1,P2,R1,LMGSEQ16; reconsider PP15 = <* <*0,0,1,1*>^<*0,1,1,0*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *> as Element of 4-tuples_on (8-tuples_on BOOLEAN) by P1,R2,R3,LMGSEQ16; reconsider Q0 = <*PP6,PP7,PP8,PP9,PP10*> as FinSequence; reconsider Q1 = <*PP11,PP12,PP13,PP14,PP15*> as FinSequence; reconsider IT = Q0^Q1 as Element of 10-tuples_on (4-tuples_on (8-tuples_on BOOLEAN)) by LMGSEQ10; A1: len Q0 = 5 & Q0.1 = PP6 & Q0.2 = PP7 & Q0.3 = PP8 & Q0.4 = PP9 & Q0.5 = PP10 by FINSEQ_4:78; A2: len Q1 = 5 & Q1.1 = PP11 & Q1.2 = PP12 & Q1.3 = PP13 & Q1.4 = PP14 & Q1.5 = PP15 by FINSEQ_4:78; 1 in Seg 5; then 1 in dom Q0 by FINSEQ_1:def 3,A1; then R1: IT.1 = PP6 by A1,FINSEQ_1:def 7; 2 in Seg 5; then 2 in dom Q0 by FINSEQ_1:def 3,A1; then R2: IT.2 = PP7 by A1,FINSEQ_1:def 7; 3 in Seg 5; then 3 in dom Q0 by FINSEQ_1:def 3,A1; then R3: IT.3 = PP8 by A1,FINSEQ_1:def 7; 4 in Seg 5; then 4 in dom Q0 by FINSEQ_1:def 3,A1; then R4: IT.4 = PP9 by A1,FINSEQ_1:def 7; 5 in Seg 5; then 5 in dom Q0 by FINSEQ_1:def 3,A1; then R5: IT.5 = PP10 by A1,FINSEQ_1:def 7; 1 in Seg 5; then 1 in dom Q1 by FINSEQ_1:def 3,A2; then R10: IT.(5+1) = Q1.1 by A1,FINSEQ_1:def 7 .= PP11 by FINSEQ_4:78; 2 in Seg 5; then 2 in dom Q1 by FINSEQ_1:def 3,A2; then R20: IT.(5+2) = Q1.2 by A1,FINSEQ_1:def 7 .= PP12 by FINSEQ_4:78; 3 in Seg 5; then 3 in dom Q1 by FINSEQ_1:def 3,A2; then R30: IT.(5+3) = Q1.3 by A1,FINSEQ_1:def 7 .= PP13 by FINSEQ_4:78; 4 in Seg 5; then 4 in dom Q1 by FINSEQ_1:def 3,A2; then R40: IT.(5+4) = Q1.4 by A1,FINSEQ_1:def 7 .= PP14 by FINSEQ_4:78; 5 in Seg 5; then 5 in dom Q1 by FINSEQ_1:def 3,A2; then R50: IT.(5+5) = Q1.5 by A1,FINSEQ_1:def 7 .= PP15 by FINSEQ_4:78; thus thesis by R1,R2,R3,R4,R5,R10,R20,R30,R40,R50; end; uniqueness proof let R1,R2 be Element of 10-tuples_on (4-tuples_on (8-tuples_on BOOLEAN)); assume A1: R1.1 = <* <*0,0,0,0*>^<*0,0,0,1*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *> & R1.2 = <* <*0,0,0,0*>^<*0,0,1,0*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *> & R1.3 = <* <*0,0,0,0*>^<*0,1,0,0*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *> & R1.4 = <* <*0,0,0,0*>^<*1,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *> & R1.5 = <* <*0,0,0,1*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *> & R1.6 = <* <*0,0,1,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *> & R1.7 = <* <*0,1,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *> & R1.8 = <* <*1,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *> & R1.9 = <* <*0,0,0,1*>^<*1,0,1,1*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *> & R1.10 = <* <*0,0,1,1*>^<*0,1,1,0*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *>; assume A2: R2.1 = <* <*0,0,0,0*>^<*0,0,0,1*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *> & R2.2 = <* <*0,0,0,0*>^<*0,0,1,0*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *> & R2.3 = <* <*0,0,0,0*>^<*0,1,0,0*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *> & R2.4 = <* <*0,0,0,0*>^<*1,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *> & R2.5 = <* <*0,0,0,1*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *> & R2.6 = <* <*0,0,1,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *> & R2.7 = <* <*0,1,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *> & R2.8 = <* <*1,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *> & R2.9 = <* <*0,0,0,1*>^<*1,0,1,1*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *> & R2.10 = <* <*0,0,1,1*>^<*0,1,1,0*>,<*0,0,0,0*>^<*0,0,0,0*>, <*0,0,0,0*>^<*0,0,0,0*>,<*0,0,0,0*>^<*0,0,0,0*> *>; R1 in 10-tuples_on (4-tuples_on (8-tuples_on BOOLEAN)); then XP1: ex v be Element of (4-tuples_on (8-tuples_on BOOLEAN))* st R1 = v & len v = 10; R2 in 10-tuples_on (4-tuples_on (8-tuples_on BOOLEAN)); then XP2: ex v be Element of (4-tuples_on (8-tuples_on BOOLEAN))* st R2 = v & len v = 10; for i be Nat st 1 <= i & i <= len R1 holds R1.i = R2.i proof let i be Nat; assume 1 <= i & i <= len R1; then i = 1 or ... or i = 10 by XP1; hence thesis by A1,A2; end; hence R1 = R2 by XP1,XP2,FINSEQ_1:14; end; end; definition let SBT; let m,i be Nat, w be Element of (4-tuples_on (8-tuples_on BOOLEAN)); assume AS: (m = 4 or m = 6 or m = 8) & i < 4*(7+m) & m <= i; func KeyExTemp(SBT,m,i,w) -> Element of (4-tuples_on (8-tuples_on BOOLEAN)) means (ex T3 be Element of (4-tuples_on (8-tuples_on BOOLEAN)) st T3 = Rcon.(i/m) & it = Op-WXOR(SubWord(SBT,RotWord(w)),T3)) if ((i mod m) = 0), (it = SubWord(SBT,w)) if (m = 8 & (i mod 8) = 4) otherwise it = w; existence proof thus (i mod m) = 0 implies ex A being Element of (4-tuples_on (8-tuples_on BOOLEAN)) st (ex T3 be Element of (4-tuples_on (8-tuples_on BOOLEAN)) st T3 = Rcon.(i/m) & A = Op-WXOR(SubWord(SBT,RotWord(w)),T3)) proof assume A1: (i mod m) = 0; m <> 0 & m divides i by A1,INT_1:62,AS; then LTT0: i/m is Integer by WSIERP_1:17; LTT1: (4*(7+m))/m = (28/m)+4 by AS; LTT2: m/m <= i/m by AS,XREAL_1:72; LTT4: i/m in NAT by INT_1:3,LTT0; LTT5: i/m < 28/m+4 by AS,XREAL_1:74,LTT1; i/m <= 10 proof now per cases by AS; case m = 4; then i/m <10+1 by AS,XREAL_1:74,LTT1; hence thesis by NAT_1:13,LTT4; end; case m = 6; hence thesis by LTT5,XXREAL_0:2; end; case m = 8; hence thesis by LTT5,XXREAL_0:2; end; end; hence thesis; end; then Q0: i/m in Seg 10 by AS,LTT2,LTT4; reconsider j = i/m as Nat by LTT4; Rcon in 10-tuples_on (4-tuples_on (8-tuples_on BOOLEAN)); then ex v be Element of (4-tuples_on (8-tuples_on BOOLEAN)) * st Rcon = v & len v = 10; then dom Rcon = Seg 10 by FINSEQ_1:def 3; then Rcon.j in rng Rcon by Q0,FUNCT_1:3; then reconsider T3 = Rcon.j as Element of (4-tuples_on (8-tuples_on BOOLEAN)); Op-WXOR(SubWord(SBT,RotWord(w)),T3) is Element of (4-tuples_on (8-tuples_on BOOLEAN)); hence thesis; end; thus m = 8 & (i mod 8) = 4 implies ex A being Element of (4-tuples_on (8-tuples_on BOOLEAN)) st (A = SubWord(SBT,w)); thus not ((i mod m) = 0) & not (m = 8 & (i mod 8) = 4) implies ex A being Element of (4-tuples_on (8-tuples_on BOOLEAN)) st A = w; end; uniqueness; consistency; end; definition let SBT; let m be Nat; assume AS: (m = 4 or m = 6 or m = 8); func KeyExpansionX(SBT,m) -> Function of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), (4*(7+m))-tuples_on (4-tuples_on (8-tuples_on BOOLEAN)) means for Key be Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds (for i be Element of NAT st i < m holds (it.Key).(i+1) = Key.(i+1)) & (for i be Element of NAT st m <= i & i < 4*(7+m) holds ex P be Element of (4-tuples_on (8-tuples_on BOOLEAN)), Q be Element of 4-tuples_on (8-tuples_on BOOLEAN) st P = (it.Key).((i-m)+1) & Q = (it.Key).i & (it.Key).(i+1) = Op-WXOR(P,KeyExTemp(SBT,m,i,Q))); existence proof defpred P0[Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), Element of (4*(7+m))-tuples_on (4-tuples_on (8-tuples_on BOOLEAN))] means (for i be Element of NAT st i < m holds $2.(i+1) = $1.(i+1))& (for i be Element of NAT st m <= i & i < 4*(7+m) holds ex P be Element of (4-tuples_on (8-tuples_on BOOLEAN)), Q be Element of 4-tuples_on (8-tuples_on BOOLEAN) st P = $2.((i-m)+1) & Q = ($2).i & $2.(i+1) = Op-WXOR(P,KeyExTemp(SBT,m,i,Q))); A1: for x being Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) ex z be Element of (4*(7+m))-tuples_on (4-tuples_on (8-tuples_on BOOLEAN)) st P0[x,z] proof let x be Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); defpred PP[Nat,set,set] means ex r,t be Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st r = $2 & t = $3 & (ex P0,Q0 be Element of 4-tuples_on (8-tuples_on BOOLEAN) st P0 = r.1 & Q0 = r.m & t.1 = Op-WXOR(P0,KeyExTemp(SBT,m,m*$1,Q0))) & for i be Nat st 1 <= i & i < m holds ex P be Element of 4-tuples_on (8-tuples_on BOOLEAN), Q be Element of 4-tuples_on (8-tuples_on BOOLEAN) st P = r.(i+1) & Q = t.i & t.(i+1) = Op-WXOR(P,KeyExTemp(SBT,m,m*$1+i,Q)); 0+m <= 7+m by XREAL_1:6; then LMMLT47M: 1*m <= 4*(7+m) by XREAL_1:66; reconsider N2 = (4*(7+m) div m )+1 as Nat; YY1: for k being Nat st 1 <= k & k < N2 for s being Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) ex y being Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st PP[k,s,y] proof let k be Nat; assume 1 <= k & k < N2; let s be Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); defpred PX[Nat,set,set] means ex P,Q be Element of 4-tuples_on (8-tuples_on BOOLEAN) st P = s.($1+1) & Q = $2 & $3 = Op-WXOR(P,KeyExTemp(SBT,m,m*k+$1,Q)); s in m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); then ex v be Element of (4-tuples_on (8-tuples_on BOOLEAN))* st s = v & len v = m; then QQ3: dom s = Seg m by FINSEQ_1:def 3; XX1: for i being Nat st 1 <= i & i < m for z being Element of (4-tuples_on (8-tuples_on BOOLEAN)) ex w being Element of (4-tuples_on (8-tuples_on BOOLEAN)) st PX[i,z,w] proof let i be Nat; assume AA1: 1 <= i & i < m; let z be Element of (4-tuples_on (8-tuples_on BOOLEAN)); 1 <= i+1 & i+1 <= m by NAT_1:13,AA1; then i+1 in Seg m; then s.(i+1) in rng s by QQ3,FUNCT_1:3; then reconsider P = s.(i+1) as Element of 4-tuples_on (8-tuples_on BOOLEAN); reconsider Q = z as Element of 4-tuples_on (8-tuples_on BOOLEAN); Op-WXOR(P,KeyExTemp(SBT,m,m*k+i,Q)) is Element of (4-tuples_on (8-tuples_on BOOLEAN)); hence thesis; end; 1 in dom s by AS,QQ3; then s.1 in rng s by FUNCT_1:3; then reconsider P0 = s.1 as Element of 4-tuples_on (8-tuples_on BOOLEAN); m in dom s by AS,QQ3; then s.m in rng s by FUNCT_1:3; then reconsider Q0 = s.m as Element of 4-tuples_on (8-tuples_on BOOLEAN); reconsider A0 = Op-WXOR(P0,KeyExTemp(SBT,m,m*k,Q0)) as Element of 4-tuples_on (8-tuples_on BOOLEAN); consider y being FinSequence of (4-tuples_on (8-tuples_on BOOLEAN)) such that A2: len y = m & (y.1 = A0 or m = 0) & for i be Nat st 1 <= i & i < m holds PX[i,y.i,y.(i+1)] from RECDEF_1:sch 4 (XX1); y in (4-tuples_on (8-tuples_on BOOLEAN))* by FINSEQ_1:def 11; then y in m-tuples_on (4-tuples_on (8-tuples_on BOOLEAN)) by A2; hence thesis by AS,A2; end; consider z being FinSequence of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) such that A2: len z = N2 & (z.1 = x or N2 = 0) & for k be Nat st 1 <= k & k < N2 holds PP[k,z.k,z.(k+1)] from RECDEF_1:sch 4 (YY1); defpred Q0[Nat,set] means ex i,j be Element of NAT, zi be Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st (($1 mod m) <> 0 implies i = ($1 div m)+1 & j = $1 mod m) & (($1 mod m) = 0 implies i = ($1 div m) & j = m) & zi = z.i & $2 = zi.j; YY2: for k be Nat st k in Seg (4*(7+m)) ex w being Element of (4-tuples_on (8-tuples_on BOOLEAN)) st Q0[k,w] proof let k be Nat; assume A1: k in Seg (4*(7+m)); QQ1: 1 <= k & k <= 4*(7+m) by A1,FINSEQ_1:1; then QQ2: k div m <= (4*(7+m)) div m by NAT_2:24; per cases; suppose C1: (k mod m) <> 0; reconsider j = (k mod m) as Element of NAT; reconsider i = (k div m)+1 as Element of NAT; 1 <= i & i <= N2 by QQ2,XREAL_1:6,NAT_1:11; then i in Seg N2; then i in dom z by A2,FINSEQ_1:def 3; then z.i in rng z by FUNCT_1:3; then reconsider zi = z.i as Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); zi in m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); then ex v be Element of (4-tuples_on (8-tuples_on BOOLEAN))* st zi = v & len v = m; then Q0: dom zi = Seg m by FINSEQ_1:def 3; 1 <= j & j <= m by C1,INT_1:58,AS,NAT_1:14; then j in dom zi by Q0; then zi.j in rng zi by FUNCT_1:3; then reconsider w = zi.j as Element of (4-tuples_on (8-tuples_on BOOLEAN)); ((k mod m) <> 0 implies i = (k div m)+1 & j = k mod m) & ((k mod m) = 0 implies i = (k div m) & j = m) & zi = z.i & w = zi.j by C1; hence thesis; end; suppose C2: (k mod m) = 0; reconsider j = m as Element of NAT by ORDINAL1:def 12; reconsider i = (k div m) as Element of NAT; QQ3: 1 <= i by NAT_D:24,QQ1,C2,NAT_2:13,AS; (k div m)+0 <= ((4*(7+m)) div m)+1 by QQ2,XREAL_1:7; then i in Seg N2 by QQ3; then i in dom z by A2,FINSEQ_1:def 3; then z.i in rng z by FUNCT_1:3; then reconsider zi = z.i as Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); zi in m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); then ex v be Element of (4-tuples_on (8-tuples_on BOOLEAN))* st zi = v & len v = m; then Q0: dom zi = Seg m by FINSEQ_1:def 3; j in Seg m by AS; then zi.j in rng zi by Q0,FUNCT_1:3; then reconsider w = zi.j as Element of (4-tuples_on (8-tuples_on BOOLEAN)); ((k mod m) <> 0 implies i = (k div m)+1 & j = k mod m) & ((k mod m) = 0 implies i = (k div m) & j = m) & zi = z.i & w = zi.j by C2; hence thesis; end; end; consider u being FinSequence of (4-tuples_on (8-tuples_on BOOLEAN)) such that YY3: dom u = Seg (4*(7+m)) & for k be Nat st k in Seg (4*(7+m)) holds Q0[k,u.k] from FINSEQ_1:sch 5(YY2); 4*(7+m) is Element of NAT by ORDINAL1:def 12; then YY4: len u = 4*(7+m) by YY3,FINSEQ_1:def 3; u in ((4-tuples_on (8-tuples_on BOOLEAN)))* by FINSEQ_1:def 11; then u in (4*(7+m))-tuples_on (4-tuples_on (8-tuples_on BOOLEAN)) by YY4; then reconsider u as Element of (4*(7+m))-tuples_on (4-tuples_on (8-tuples_on BOOLEAN)); take u; LX3: for i be Element of NAT st i < m holds u.(i+1) = x.(i+1) proof let k be Element of NAT; assume k < m; then LX31: 1 <= k+1 & k+1 <= m by NAT_1:11,NAT_1:13; then 1 <= k+1 & k+1 <= 4*(7+m) by LMMLT47M,XXREAL_0:2; then k+1 in Seg (4*(7+m)); then consider i,j be Element of NAT, zi be Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) such that LX34: (((k+1) mod m) <> 0 implies i = ((k+1) div m)+1 & j = (k+1) mod m) & (((k+1) mod m) = 0 implies i = ((k+1) div m) & j = m) & zi = z.i & u.(k+1) = zi.j by YY3; per cases; suppose C1: ((k+1) mod m) <> 0; C11: (k+1) < m proof assume not (k+1) < m; then (k+1) = m by XXREAL_0:1,LX31; hence contradiction by NAT_D:25,C1; end; then (k+1) div m = 0 by NAT_D:27; hence u.(k+1) = x.(k+1) by C11,NAT_D:24,LX34,A2; end; suppose C2: ((k+1) mod m) = 0; (k+1) = m proof assume not (k+1) = m; then k+1 < m by LX31,XXREAL_0:1; hence contradiction by NAT_D:24,C2; end; hence u.(k+1) = x.(k+1) by LX34,C2,INT_1:49,A2; end; end; for k be Element of NAT st m <= k & k < 4*(7+m) holds ex P be Element of (4-tuples_on (8-tuples_on BOOLEAN)), Q be Element of 4-tuples_on (8-tuples_on BOOLEAN) st P = u.((k-m)+1) & Q = u.k & u.(k+1) = Op-WXOR(P,KeyExTemp(SBT,m,k,Q)) proof let k be Element of NAT; assume AS1: m <= k & k < 4*(7+m); then 1 <= k & k <= 4*(7+m) by XXREAL_0:2,AS; then k in Seg (4*(7+m)); then consider i,j be Element of NAT, zi be Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) such that LX34: ((k mod m) <> 0 implies i = (k div m)+1 & j = k mod m) & ((k mod m) = 0 implies i = (k div m) & j = m) & zi = z.i & u.k = zi.j by YY3; NLX32: 1 <= k+1 & k+1 <= 4*(7+m) by AS1,NAT_1:11,NAT_1:13; then k+1 in Seg (4*(7+m)); then consider i1,j1 be Element of NAT, zi1 be Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) such that NLX34: (((k+1) mod m) <> 0 implies i1 = ((k+1) div m)+1 & j1 = (k+1) mod m) & (((k+1) mod m) = 0 implies i1 = ((k+1) div m) & j1 = m) & zi1 = z.i1 & u.(k+1) = zi1.j1 by YY3; reconsider km0 = k-m as Element of NAT by AS1,XREAL_1:48,INT_1:3; reconsider km1 = km0+1 as Element of NAT; k+1-m <= 4*(7+m)-0 by NLX32,XREAL_1:13; then 1 <= km1 & km1 <= 4*(7+m) by NAT_1:11; then km1 in Seg (4*(7+m)); then consider i2,j2 be Element of NAT, zi2 be Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) such that LLX34: ((km1 mod m) <> 0 implies i2 = (km1 div m)+1 & j2 = km1 mod m) & ((km1 mod m) = 0 implies i2 = (km1 div m) & j2 = m) & zi2 = z.i2 & u.km1 = zi2.j2 by YY3; per cases; suppose C1: (k mod m) <> 0; reconsider i0 = k div m as Element of NAT; DD1: ((4*(7+m)) div m)+0 < ((4*(7+m)) div m)+1 by XREAL_1:8; k div m <= (4*(7+m)) div m by AS1,NAT_2:24; then 1 <= i0 & i0 < N2 by DD1,XXREAL_0:2,AS,NAT_2:13,AS1; then consider r,t be Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) such that C16: r = z.i0 & t = z.(i0+1) & (ex P0,Q0 be Element of 4-tuples_on (8-tuples_on BOOLEAN) st P0 = r.1 & Q0 = r.m & t.1 = Op-WXOR(P0,KeyExTemp(SBT,m,m*i0,Q0))) & for n be Nat st 1 <= n & n < m holds ex P be Element of 4-tuples_on (8-tuples_on BOOLEAN), Q be Element of 4-tuples_on (8-tuples_on BOOLEAN) st P = r.(n+1) & Q = t.n & t.(n+1) = Op-WXOR(P,KeyExTemp(SBT,m,i0*m+n,Q)) by A2; 1 <= j & j < m by AS,INT_1:58,LX34,C1,NAT_1:14; then consider P be Element of 4-tuples_on (8-tuples_on BOOLEAN), Q be Element of 4-tuples_on (8-tuples_on BOOLEAN) such that C18: P = r.(j+1) & Q = t.j & t.(j+1) = Op-WXOR(P,KeyExTemp(SBT,m,i0*m+j,Q)) by C16; per cases; suppose NC1: ((k+1) mod m) <> 0; NC16: zi1 = zi by NLX34,NC1,AS,XLMOD01,LX34,C1; C21: u.(k+1) = t.(j+1) by NLX34,NC16,NC1,AS,XLMOD02,LX34,C1,C16; C22X: km1 = (k+1)-m; LC12: i2 = ((k+1) div m)-1+1 by NC1,XLMOD03,C22X,LLX34,AS,XLMOD04 .= i0 by AS,XLMOD01,NC1; LC13: j2 = j1 by LLX34,C22X,XLMOD03,NLX34; C19: u.(k-m+1) = r.(j+1) by LLX34,LC13,LC12,C16,NLX34,NC1,AS,XLMOD02,LX34,C1; C22: k = i0*m+j by AS,INT_1:59,LX34,C1; thus ex P be Element of (4-tuples_on (8-tuples_on BOOLEAN)), Q be Element of 4-tuples_on (8-tuples_on BOOLEAN) st P = u.((k-m)+1) & Q = u.k & u.(k+1) = Op-WXOR(P,KeyExTemp(SBT,m,k,Q)) by C18,C19,C16,LX34,C1,C21,C22; end; suppose MC1: ((k+1) mod m) = 0; NC13: j1 = m-1+1 by NLX34,MC1 .= j+1 by AS,XLMOD02X,MC1,LX34; C21: u.(k+1) = t.(j+1) by NLX34,MC1,XLMOD01X,NC13,C16; C22X: km1 = (k+1)-m; LC12: i2 = ((k+1) div m)-1 by C22X,MC1,XLMOD03,LLX34,AS,XLMOD04 .= (k div m)+1-1 by AS,XLMOD01X,MC1 .= i0; C19: u.(k-m+1) = r.(j+1) by LLX34,C22X,XLMOD03,NLX34,LC12,C16,NC13; C22: k = i0*m+j by AS,INT_1:59,LX34,C1; thus ex P be Element of (4-tuples_on (8-tuples_on BOOLEAN)), Q be Element of 4-tuples_on (8-tuples_on BOOLEAN) st P = u.((k-m)+1) & Q = u.k & u.(k+1) = Op-WXOR(P,KeyExTemp(SBT,m,k,Q)) by C18,C19,LX34,C16,C1,C21,C22; end; end; suppose C2: (k mod m) = 0; DD1: ((4*(7+m)) div m)+0 < ((4*(7+m)) div m)+1 by XREAL_1:8; k div m <= (4*(7+m)) div m by AS1,NAT_2:24; then 1 <= i & i < N2 by DD1,XXREAL_0:2,C2,LX34,AS,NAT_2:13,AS1; then consider r,t be Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) such that C16: r = z.i & t = z.(i+1) & (ex P0,Q0 be Element of 4-tuples_on (8-tuples_on BOOLEAN) st P0 = r.1 & Q0 = r.m & t.1 = Op-WXOR(P0,KeyExTemp(SBT,m,m*i,Q0))) & for n be Nat st 1 <= n & n < m holds ex P be Element of 4-tuples_on (8-tuples_on BOOLEAN), Q be Element of 4-tuples_on (8-tuples_on BOOLEAN) st P = r.(n+1) & Q = t.n & t.(n+1) = Op-WXOR(P,KeyExTemp(SBT,m,i*m+n,Q)) by A2; NC1X: ((k+1) mod m) = ((0 qua Nat)+1) mod m by C2,NAT_D:23 .= 1 by NAT_D:14,AS; C21: u.(k+1) = t.1 by NLX34,NC1X,AS,XLMOD01,C2,LX34,C16; C22X: km1 = (k+1)-m; LC12: i2 = ((k+1) div m)-1+1 by NC1X,XLMOD03,C22X,LLX34,AS,XLMOD04 .= i by AS,XLMOD01,NC1X,C2,LX34; C19: u.(k-m+1) = r.1 by LLX34,XLMOD03,C22X,LC12,C16,NC1X; C22: k = (k div m)*m+(k mod m) by AS,INT_1:59 .= i*m by C2,LX34; thus ex P be Element of (4-tuples_on (8-tuples_on BOOLEAN)), Q be Element of 4-tuples_on (8-tuples_on BOOLEAN) st P = u.((k-m)+1) & Q = u.k & u.(k+1) = Op-WXOR(P,KeyExTemp(SBT,m,k,Q)) by C19,LX34,C16,C2,C21,C22; end; end; hence P0[x,u] by LX3; end; consider I be Function of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), (4*(7+m))-tuples_on (4-tuples_on (8-tuples_on BOOLEAN)) such that A2: for x being Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds P0[x,I.x] from FUNCT_2:sch 3(A1); take I; thus thesis by A2; end; uniqueness proof let H1,H2 be Function of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), (4*(7+m))-tuples_on (4-tuples_on (8-tuples_on BOOLEAN)); assume AA1: for Key be Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds (for i be Element of NAT st i < m holds (H1.Key).(i+1) = Key.(i+1)) & (for i be Element of NAT st m <= i & i < 4*(7+m) holds ex P be Element of (4-tuples_on (8-tuples_on BOOLEAN)), Q be Element of 4-tuples_on (8-tuples_on BOOLEAN) st P = (H1.Key).((i-m)+1) & Q = (H1.Key).i & (H1.Key).(i+1) = Op-WXOR(P,KeyExTemp(SBT,m,i,Q))); assume AA2: for Key be Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds (for i be Element of NAT st i < m holds (H2.Key).(i+1) = Key.(i+1)) & (for i be Element of NAT st m <= i & i < 4*(7+m) holds ex P be Element of (4-tuples_on (8-tuples_on BOOLEAN)), Q be Element of 4-tuples_on (8-tuples_on BOOLEAN) st P = (H2.Key).((i-m)+1) & Q = (H2.Key).i & (H2.Key).(i+1) = Op-WXOR(P,KeyExTemp(SBT,m,i,Q))); now let input be Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); (H1.input) in (4*(7+m))-tuples_on (4-tuples_on (8-tuples_on BOOLEAN)); then XX1: ex s be Element of (4-tuples_on (8-tuples_on BOOLEAN))* st (H1.input) = s & len s = (4*(7+m)); reconsider H1i = (H1.input) as Element of (4-tuples_on (8-tuples_on BOOLEAN))* by XX1; (H2.input) in (4*(7+m))-tuples_on (4-tuples_on (8-tuples_on BOOLEAN)); then XX2: ex s be Element of (4-tuples_on (8-tuples_on BOOLEAN))* st (H2.input) = s & len s = (4*(7+m)); reconsider H2i = (H2.input) as Element of (4-tuples_on (8-tuples_on BOOLEAN))* by XX2; defpred PN[Nat] means (m <= $1 & $1 <= 4*(7+m)) implies for k be Element of NAT st 1 <= k & k <= $1 holds (H1.input).k = (H2.input).k; PN0: PN[0]; PN1: for i be Nat st PN[i] holds PN[i+1] proof let i be Nat; assume A1: PN[i]; assume A2: m <= i+1 & i+1 <= 4*(7+m); per cases; suppose C10: m = i+1; thus for k be Element of NAT st 1 <= k & k <= i+1 holds (H1.input).k = (H2.input).k proof let k be Element of NAT; assume B1: 1 <= k & k <= i+1; k-1 < k by XREAL_1:44; then B2: k-1 < m by C10,B1,XXREAL_0:2; reconsider k1 = k-1 as Element of NAT by XREAL_1:48,B1,INT_1:3; thus (H1.input).k = input.(k1+1) by B2,AA1 .= (H2.input).k by B2,AA2; end; end; suppose m <> i+1; then C10X: m < i+1 by A2,XXREAL_0:1; i < i+1 by XREAL_1:29; then C11Z: i < 4*(7+m) by A2,XXREAL_0:2; thus for k be Element of NAT st 1 <= k & k <= i+1 holds (H1.input).k = (H2.input).k proof let k be Element of NAT; assume C13: 1 <= k & k <= i+1; then reconsider k1 = k-1 as Element of NAT by XREAL_1:48,INT_1:3; per cases; suppose C14: k1 < m; thus (H1.input).k = input.(k1+1) by C14,AA1 .= (H2.input).k by C14,AA2; end; suppose C15: m <= k1; k-1 <= i+1-1 by C13,XREAL_1:9; then C16: m <= k1 & k1 < 4*(7+m) by C11Z,XXREAL_0:2,C15; then consider PP1 be Element of (4-tuples_on (8-tuples_on BOOLEAN)), QQ1 be Element of 4-tuples_on (8-tuples_on BOOLEAN) such that C17: PP1 = (H1.input).((k1-m)+1) & QQ1 = (H1.input).k1 & (H1.input).(k1+1) = Op-WXOR(PP1,KeyExTemp(SBT,m,k1,QQ1)) by AA1; consider PP2 be Element of (4-tuples_on (8-tuples_on BOOLEAN)), QQ2 be Element of 4-tuples_on (8-tuples_on BOOLEAN) such that C18: PP2 = (H2.input).((k1-m)+1) & QQ2 = (H2.input).k1 & (H2.input).(k1+1) = Op-WXOR(PP2,KeyExTemp(SBT,m,k1,QQ2)) by AA2,C16; C190: k-1 <= i+1-1 by XREAL_1:9,C13; then C191: 1 <= k1 & k1 <= i by C15,AS,XXREAL_0:2; C24X: 0 <= k1-m by C15,XREAL_1:48; then C25X: 1+0 <= k1-m+1 by XREAL_1:6; k1-(m-1) <= k1 by AS,XREAL_1:43; then C25: 1 <= (k1-m)+1 & (k1-m)+1 <= i by C190,XXREAL_0:2,C25X; reconsider k1m1 = (k1-m)+1 as Element of NAT by C24X,INT_1:3; C21: (H1.input).k1m1 = (H2.input).k1m1 by A2,C10X,NAT_1:13,A1,C25; thus (H1.input).k = (H2.input).k by C21,C17,C18,C191,A2,C10X,NAT_1:13,A1; end; end; end; end; L10: for i be Nat holds PN[i] from NAT_1:sch 2(PN0,PN1); L1: now let i be Element of NAT; assume A1: m <=i & i <= 4*(7+m); 1 <= i & i <= i by AS,A1,XXREAL_0:2; hence (H1.input).i = (H2.input).i by L10,A1; end; now let i0 be Nat; assume P13: 1 <= i0 & i0 <= len H1i; then reconsider i = i0-1 as Element of NAT by XREAL_1:48,INT_1:3; now per cases; suppose C1: i0 <= m; i < i0 by XREAL_1:44; then C11: i < m by C1,XXREAL_0:2; thus H1i.i0 = input.(i+1) by C11,AA1 .= H2i.i0 by C11,AA2; end; suppose C3: m < i0; i+1 in Seg len H1i by P13; hence H1i.i0 = H2i.i0 by L1,C3,XX1,P13; end; end; hence H1i.i0 = H2i.i0; end; hence H1.input = H2.input by XX1,XX2,FINSEQ_1:def 17; end; hence H1 = H2 by FUNCT_2:63; end; end; definition let SBT; let m be Nat; func KeyExpansion(SBT,m) -> Function of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), (7+m)-tuples_on(4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN))) means for Key be Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds ex w be Element of (4*(7+m))-tuples_on (4-tuples_on (8-tuples_on BOOLEAN)) st w = (KeyExpansionX(SBT,m)).Key & for i be Nat st i < 7+m holds (it.Key).(i+1) = <*w.(4*i+1),w.(4*i+2),w.(4*i+3),w.(4*i+4)*>; existence proof defpred P0[Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), Element of (7+m)-tuples_on(4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)))] means ex w be Element of (4*(7+m))-tuples_on (4-tuples_on (8-tuples_on BOOLEAN)) st w = (KeyExpansionX(SBT,m)).$1 & for i be Nat st i < 7+m holds $2.(i+1) = <*w.(4*i+1),w.(4*i+2),w.(4*i+3),w.(4*i+4)*>; A1: for x being Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) ex z be Element of (7+m)-tuples_on(4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN))) st P0[x,z] proof let x be Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); reconsider w = (KeyExpansionX(SBT,m)).x as Element of (4*(7+m))-tuples_on (4-tuples_on (8-tuples_on BOOLEAN)); w in (4*(7+m))-tuples_on (4-tuples_on (8-tuples_on BOOLEAN)); then XX1: ex s be Element of (4-tuples_on (8-tuples_on BOOLEAN))* st w = s & len s = (4*(7+m)); reconsider w0 = w as Element of (4-tuples_on (8-tuples_on BOOLEAN))* by XX1; reconsider m7 = 7+m as Element of NAT by ORDINAL1:def 12; reconsider m47 = (4*(7+m)) as Element of NAT by ORDINAL1:def 12; defpred P[Nat,set] means ex n be Element of NAT st n = $1-1 & $2 = <*w.(4*n+1),w.(4*n+2),w.(4*n+3),w.(4*n+4)*>; P1: for k be Nat st k in Seg m7 ex z being Element of 4-tuples_on (4-tuples_on (8-tuples_on BOOLEAN)) st P[k,z] proof let k be Nat; assume k in Seg m7; then ZZ1: 1 <= k & k <= m7 by FINSEQ_1:1; then reconsider n = k-1 as Element of NAT by XREAL_1:48,INT_1:3; ZZ3: 4*(n+1) <= 4*m7 by ZZ1,XREAL_1:64; ZZ4: 0+1 <= 4*n+1 by XREAL_1:7; ZZ7: 4*n+1 <= 4*n+4 by XREAL_1:7; ZZ8: 4*n+2 <= 4*n+4 by XREAL_1:7; ZZ9: 4*n+3 <= 4*n+4 by XREAL_1:7; 4*n+1 <= 4*m7 by ZZ7,ZZ3,XXREAL_0:2; then X1: (4*n+1) in Seg m47 by ZZ4; ZZ10: 1 <= 4*n+2 by ZZ4,XREAL_1:7; 4*n+2 <= 4*m7 by ZZ8,ZZ3,XXREAL_0:2; then X2: (4*n+2) in Seg m47 by ZZ10; ZZ11: 1 <= 4*n+3 by ZZ4,XREAL_1:7; 4*n+3 <= 4*m7 by ZZ9,ZZ3,XXREAL_0:2; then X3: (4*n+3) in Seg m47 by ZZ11; ZZ12: 1 <= 4*n+4 by ZZ4,XREAL_1:7; X4: (4*n+4) in Seg m47 by ZZ3,ZZ12; X5: dom w = Seg m47 by FINSEQ_1:def 3,XX1; w.(4*n+1) in rng w by X5,X1,FUNCT_1:3; then reconsider w1 = w.(4*n+1) as Element of (4-tuples_on (8-tuples_on BOOLEAN)); w.(4*n+2) in rng w by X5,X2,FUNCT_1:3; then reconsider w2 = w.(4*n+2) as Element of (4-tuples_on (8-tuples_on BOOLEAN)); w.(4*n+3) in rng w by X5,X3,FUNCT_1:3; then reconsider w3 = w.(4*n+3) as Element of (4-tuples_on (8-tuples_on BOOLEAN)); w.(4*n+4) in rng w by X5,X4,FUNCT_1:3; then reconsider w4 = w.(4*n+4) as Element of (4-tuples_on (8-tuples_on BOOLEAN)); reconsider z = <*w1,w2,w3,w4*> as Element of 4-tuples_on (4-tuples_on (8-tuples_on BOOLEAN)) by LMGSEQ4; z = <*w.(4*n+1),w.(4*n+2),w.(4*n+3),w.(4*n+4)*>; hence thesis; end; consider p being FinSequence of 4-tuples_on (4-tuples_on (8-tuples_on BOOLEAN)) such that P3: dom p = Seg m7 & for k be Nat st k in Seg m7 holds P[k,p.k] from FINSEQ_1:sch 5(P1); P4: len p = m7 by P3,FINSEQ_1:def 3; p in (4-tuples_on (4-tuples_on (8-tuples_on BOOLEAN)))* by FINSEQ_1:def 11; then p in m7-tuples_on (4-tuples_on (4-tuples_on (8-tuples_on BOOLEAN))) by P4; then reconsider p as Element of (7+m)-tuples_on(4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN))); take p; now let i be Nat; assume i < 7+m; then AA2: i+1 <= 7+m by NAT_1:13; 1 <= i+1 by NAT_1:11; then i+1 in Seg m7 by AA2; then ex n be Element of NAT st n = (i+1)-1 & p.(i+1) = <*w.(4*n+1),w.(4*n+2),w.(4*n+3),w.(4*n+4)*> by P3; hence p.(i+1) = <*w.(4*i+1),w.(4*i+2),w.(4*i+3),w.(4*i+4)*>; end; hence thesis; end; consider I be Function of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), (7+m)-tuples_on(4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN))) such that A2: for x being Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds P0[x,I.x] from FUNCT_2:sch 3(A1); take I; thus thesis by A2; end; uniqueness proof let H1,H2 be Function of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), (7+m)-tuples_on(4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN))); assume A1: for Key be Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds ex w be Element of (4*(7+m))-tuples_on (4-tuples_on (8-tuples_on BOOLEAN)) st w = (KeyExpansionX(SBT,m)).Key & for i be Nat st i < 7+m holds (H1.Key).(i+1) = <*w.(4*i+1),w.(4*i+2),w.(4*i+3),w.(4*i+4)*>; assume A2: for Key be Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds ex w be Element of (4*(7+m))-tuples_on (4-tuples_on (8-tuples_on BOOLEAN)) st w = (KeyExpansionX(SBT,m)).Key & for i be Nat st i <7+m holds (H2.Key).(i+1) = <*w.(4*i+1),w.(4*i+2),w.(4*i+3),w.(4*i+4)*>; now let input be Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); consider w1 be Element of (4*(7+m))-tuples_on (4-tuples_on (8-tuples_on BOOLEAN)) such that P1: w1 = (KeyExpansionX(SBT,m)).input & for i be Nat st i < 7+m holds (H1.input).(i+1) = <*w1.(4*i+1),w1.(4*i+2),w1.(4*i+3),w1.(4*i+4)*> by A1; consider w2 be Element of (4*(7+m))-tuples_on (4-tuples_on (8-tuples_on BOOLEAN)) such that P2: w2 = (KeyExpansionX(SBT,m)).input & for i be Nat st i < 7+m holds (H2.input).(i+1) = <*w2.(4*i+1),w2.(4*i+2),w2.(4*i+3),w2.(4*i+4)*> by A2; (H1.input) in (7+m)-tuples_on(4-tuples_on (4-tuples_on (8-tuples_on BOOLEAN))); then P3: ex s be Element of (4-tuples_on (4-tuples_on (8-tuples_on BOOLEAN)))* st (H1.input) = s & len s = (7+m); (H2.input) in (7+m)-tuples_on (4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN))); then P4: ex s be Element of (4-tuples_on (4-tuples_on (8-tuples_on BOOLEAN)))* st (H2.input) = s & len s = (7+m); now let i be Nat; assume P5: 1 <= i & i <= len (H1.input); then i-1 in NAT by XREAL_1:48,INT_1:3; then reconsider i0 = i-1 as Nat; i < (7+m)+1 by P3,P5,NAT_1:13; then P6: i-1 < (7+m)+1-1 by XREAL_1:14; thus (H1.input).i = (H1.input).(i0+1) .= <*w2.(4*i0+1),w2.(4*i0+2),w2.(4*i0+3),w2.(4*i0+4)*> by P6,P1,P2 .= (H2.input).(i0+1) by P6,P2 .= (H2.input).i; end; hence (H1.input) = (H2.input) by P3,P4,FINSEQ_1:def 17; end; hence H1 = H2 by FUNCT_2:63; end; end; begin :: Encryption and Decryption reserve MCFunc for Permutation of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); reserve MixColumns for Permutation of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); definition let SBT; let MCFunc; let m be Nat; let text be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); let Key be Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); func AES-ENC(SBT,MCFunc,text,Key) -> Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) means :defENC: ex seq be FinSequence of (4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN))) st len seq = 7+m-1 & (ex Keyi1 be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st Keyi1 = ((KeyExpansion(SBT,m)).(Key)).1 & seq.1 = AddRoundKey.(text,Keyi1)) & (for i be Nat st 1 <= i & i < 7+m-1 holds ex Keyi be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st Keyi = ((KeyExpansion(SBT,m)).(Key)).(i+1) & seq.(i+1) = AddRoundKey.((MCFunc*ShiftRows*SubBytes(SBT)).(seq.i),Keyi)) & ex KeyNr be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st KeyNr = ((KeyExpansion(SBT,m)).(Key)).(7+m) & it = AddRoundKey.((ShiftRows*SubBytes(SBT)).(seq.(7+m-1)),KeyNr); existence proof 1+0 < 7+m by XREAL_1:8; then N1: 0 < 7+m-1 by XREAL_1:50; then 7+m-1 in NAT by INT_1:3; then reconsider Nr = 7+m-1 as Nat; ZZ1: (KeyExpansion(SBT,m)).(Key) in (Nr+1)-tuples_on(4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN))); reconsider kky = (KeyExpansion(SBT,m)).(Key) as Element of (Nr+1)-tuples_on(4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN))); XX12: ex s be Element of (4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)))* st kky = s & len s = (Nr+1) by ZZ1; defpred P[Nat,set,set] means ex Keyi be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st Keyi = ((KeyExpansion(SBT,m)).(Key)).($1+1) & $3 = AddRoundKey.((MCFunc*ShiftRows*SubBytes(SBT)).$2,Keyi); 1+0 <= 7+m by XREAL_1:7; then 1 in Seg (Nr+1); then 1 in dom (kky) by FINSEQ_1:def 3,XX12; then ((KeyExpansion(SBT,m)).(Key)).1 in rng kky by FUNCT_1:3; then reconsider Keyi1 = ((KeyExpansion(SBT,m)).(Key)).1 as Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); reconsider I0 = AddRoundKey.(text,Keyi1) as Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); X1: for n being Nat st 1 <= n & n < Nr for z being Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds ex y being Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st P[n,z,y] proof let n be Nat; assume X11: 1 <= n & n < Nr; let z be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); X111: n+1 <= Nr+1 by XREAL_1:7,X11; 0+1 <= n+1 by XREAL_1:7; then n+1 in Seg (Nr+1) by X111; then n+1 in dom (kky) by FINSEQ_1:def 3,XX12; then ((KeyExpansion(SBT,m)).(Key)).(n+1) in rng kky by FUNCT_1:3; then reconsider Keyi = ((KeyExpansion(SBT,m)).(Key)).(n+1) as Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); reconsider y = AddRoundKey.((MCFunc*ShiftRows*SubBytes(SBT)).z,Keyi) as Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); take y; thus P[n,z,y]; end; consider seq be FinSequence of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) such that X2: len seq = Nr & (seq.1 = I0 or Nr = 0) & for i be Nat st 1 <= i & i < Nr holds P[i,seq.i,seq.(i+1)] from RECDEF_1:sch 4(X1); Nr in Seg Nr by FINSEQ_1:3,N1; then Nr in dom seq by FINSEQ_1:def 3,X2; then seq.Nr in rng seq by FUNCT_1:3; then reconsider seq10 = seq.Nr as Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); Nr+1 in Seg (Nr+1) by FINSEQ_1:3; then Nr+1 in dom (kky) by FINSEQ_1:def 3,XX12; then ((KeyExpansion(SBT,m)).(Key)).(Nr+1) in rng kky by FUNCT_1:3; then reconsider KeyNr = ((KeyExpansion(SBT,m)).(Key)).(Nr+1) as Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); reconsider w = AddRoundKey.((ShiftRows*SubBytes(SBT)).(seq10),KeyNr) as Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); w = AddRoundKey.((ShiftRows*SubBytes(SBT)).(seq.Nr),KeyNr); hence thesis by XREAL_1:8,X2; end; uniqueness proof let s1,s2 be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); 1+0 < 7+m by XREAL_1:8; then 0 < 7+m-1 by XREAL_1:50; then 7+m-1 in NAT by INT_1:3; then reconsider Nr = 7+m-1 as Nat; assume A1: ex seq be FinSequence of (4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN))) st len seq = 7+m-1 & (ex Keyi1 be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st Keyi1 = ((KeyExpansion(SBT,m)).(Key)).1 & seq.1 = AddRoundKey.(text,Keyi1)) & (for i be Nat st 1 <= i & i < 7+m-1 holds ex Keyi be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st Keyi = ((KeyExpansion(SBT,m)).(Key)).(i+1) & seq.(i+1) = AddRoundKey.((MCFunc*ShiftRows*SubBytes(SBT)).(seq.i),Keyi)) & ex KeyNr be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st KeyNr = ((KeyExpansion(SBT,m)).(Key)).(7+m) & s1 = AddRoundKey.((ShiftRows*SubBytes(SBT)).(seq.(7+m-1)),KeyNr); assume A2: ex seq be FinSequence of (4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN))) st len seq = 7+m-1 & (ex Keyi1 be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st Keyi1 = ((KeyExpansion(SBT,m)).(Key)).1 & seq.1 = AddRoundKey.(text,Keyi1)) & (for i be Nat st 1 <= i & i < 7+m-1 holds ex Keyi be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st Keyi = ((KeyExpansion(SBT,m)).(Key)).(i+1) & seq.(i+1) = AddRoundKey.((MCFunc*ShiftRows*SubBytes(SBT)).(seq.i),Keyi)) & ex KeyNr be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st KeyNr = ((KeyExpansion(SBT,m)).(Key)).(7+m) & s2 = AddRoundKey.((ShiftRows*SubBytes(SBT)).(seq.(7+m-1)),KeyNr); consider seq1 be FinSequence of (4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN))) such that P1: len seq1 = Nr & (ex Keyi1 be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st Keyi1 = ((KeyExpansion(SBT,m)).(Key)).1 & seq1.1 = AddRoundKey.(text,Keyi1)) & (for i be Nat st 1 <= i & i < Nr holds ex Keyi be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st Keyi = ((KeyExpansion(SBT,m)).(Key)).(i+1) & seq1.(i+1) = AddRoundKey.((MCFunc*ShiftRows*SubBytes(SBT)).(seq1.i),Keyi)) & ex KeyNr be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st KeyNr = ((KeyExpansion(SBT,m)).(Key)).(Nr+1) & s1 = AddRoundKey.((ShiftRows*SubBytes(SBT)).(seq1.(Nr)),KeyNr) by A1; consider seq2 be FinSequence of (4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN))) such that P2: len seq2 = Nr & (ex Keyi1 be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st Keyi1 = ((KeyExpansion(SBT,m)).(Key)).1 & seq2.1 = AddRoundKey.(text,Keyi1)) & (for i be Nat st 1 <= i & i < Nr holds ex Keyi be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st Keyi = ((KeyExpansion(SBT,m)).(Key)).(i+1) & seq2.(i+1) = AddRoundKey.((MCFunc*ShiftRows*SubBytes(SBT)).(seq2.i),Keyi)) & ex KeyNr be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st KeyNr = ((KeyExpansion(SBT,m)).(Key)).(Nr+1) & s2 = AddRoundKey.((ShiftRows*SubBytes(SBT)).(seq2.(Nr)),KeyNr) by A2; defpred EQ[Nat] means 1 <= $1 & $1 <= len seq1 implies seq1.$1 = seq2.$1; Q50: EQ[0]; Q51: for i be Nat st EQ[i] holds EQ[i+1] proof let i be Nat; assume Q52: EQ[i]; assume 1 <= i+1 & i+1 <= len seq1; then Q54: 1-1 <= i+1-1 & i+1-1 <= len seq1-1 by XREAL_1:9; Q550: (len seq1)-1 <= (len seq1)-0 by XREAL_1:13; per cases; suppose C1: i = 0; thus seq1.(i+1) = seq2.(i+1) by C1,P1,P2; end; suppose Q560: i <> 0; Nr-1 < Nr-0 by XREAL_1:15; then XX1: 1 <= i & i < Nr by Q560,NAT_1:14,P1,Q54,XXREAL_0:2; then Q60: ex Keyi be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st Keyi = ((KeyExpansion(SBT,m)).(Key)).(i+1) & seq1.(i+1) = AddRoundKey.((MCFunc*ShiftRows*SubBytes(SBT)).(seq1.i),Keyi) by P1; ex Keyi be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st Keyi = ((KeyExpansion(SBT,m)).(Key)).(i+1) & seq2.(i+1) = AddRoundKey.((MCFunc*ShiftRows*SubBytes(SBT)).(seq2.i),Keyi) by P2,XX1; hence seq1.(i+1) = seq2.(i+1) by Q560,NAT_1:14,Q550,Q54,XXREAL_0:2,Q52,Q60; end; end; for i be Nat holds EQ[i] from NAT_1:sch 2(Q50,Q51); hence s1 = s2 by P1,P2,FINSEQ_1:14; end; end; definition let SBT; let MCFunc; let m be Nat; let text be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); let Key be Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); func AES-DEC(SBT,MCFunc,text,Key) -> Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) means :defDEC: ex seq be FinSequence of (4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN))) st len seq = 7+m-1 & (ex Keyi1 be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st Keyi1 = (Rev((KeyExpansion(SBT,m)).(Key))).1 & seq.1 = (InvSubBytes(SBT)*InvShiftRows).(AddRoundKey.(text,Keyi1))) & (for i be Nat st 1 <= i & i < 7+m-1 holds ex Keyi be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st Keyi = (Rev((KeyExpansion(SBT,m)).(Key))).(i+1) & seq.(i+1) = (InvSubBytes(SBT)*InvShiftRows*(MCFunc")).(AddRoundKey.(seq.i,Keyi))) & ex KeyNr be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st KeyNr = (Rev((KeyExpansion(SBT,m)).(Key))).(7+m) & it = AddRoundKey.(seq.(7+m-1),KeyNr); existence proof 1+0 < 7+m by XREAL_1:8; then N1: 0 < 7+m-1 by XREAL_1:50; then 7+m-1 in NAT by INT_1:3; then reconsider Nr = 7+m-1 as Nat; ZZ1: Rev((KeyExpansion(SBT,m)).(Key)) in (Nr+1)-tuples_on(4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN))); reconsider kky = Rev((KeyExpansion(SBT,m)).(Key)) as Element of (Nr+1)-tuples_on(4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN))); XX12: ex s be Element of (4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)))* st kky = s & len s = Nr+1 by ZZ1; defpred P[Nat,set,set] means ex Keyi be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st Keyi = (Rev((KeyExpansion(SBT,m)).(Key))).($1+1) & $3 = (InvSubBytes(SBT)*InvShiftRows*(MCFunc")).(AddRoundKey.($2,Keyi)); 1+0 <= 7+m by XREAL_1:7; then 1 in Seg (Nr+1); then 1 in dom (kky) by FINSEQ_1:def 3,XX12; then (Rev((KeyExpansion(SBT,m)).(Key))).1 in rng kky by FUNCT_1:3; then reconsider Keyi1 = (Rev((KeyExpansion(SBT,m)).(Key))).1 as Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); reconsider I0 = (InvSubBytes(SBT)*InvShiftRows).(AddRoundKey.(text,Keyi1)) as Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); X1: for n being Nat st 1 <= n & n < Nr for z being Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds ex y being Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st P[n,z,y] proof let n be Nat; assume X11: 1 <= n & n < Nr; let z be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); X111: n+1 <= Nr+1 by XREAL_1:7,X11; 0+1 <= n+1 by XREAL_1:7; then n+1 in Seg (Nr+1) by X111; then n+1 in dom (kky) by FINSEQ_1:def 3,XX12; then (Rev((KeyExpansion(SBT,m)).(Key))).(n+1) in rng kky by FUNCT_1:3; then reconsider Keyi = (Rev((KeyExpansion(SBT,m)).(Key))).(n+1) as Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); reconsider y = (InvSubBytes(SBT)*InvShiftRows*(MCFunc")).(AddRoundKey.(z,Keyi)) as Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); take y; thus P[n,z,y]; end; consider seq be FinSequence of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) such that X2: len seq = Nr & (seq.1 = I0 or Nr = 0) & for i be Nat st 1 <= i & i < Nr holds P[i,seq.i,seq.(i+1)] from RECDEF_1:sch 4(X1); Nr in Seg Nr by FINSEQ_1:3,N1; then Nr in dom seq by FINSEQ_1:def 3,X2; then seq.Nr in rng seq by FUNCT_1:3; then reconsider seq10 = seq.Nr as Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); Nr+1 in Seg (Nr+1) by FINSEQ_1:3; then Nr+1 in dom (kky) by FINSEQ_1:def 3,XX12; then (Rev((KeyExpansion(SBT,m)).(Key))).(Nr+1) in rng kky by FUNCT_1:3; then reconsider KeyNr = (Rev((KeyExpansion(SBT,m)).(Key))).(Nr+1) as Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); reconsider w = AddRoundKey.((seq10),KeyNr) as Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); w = AddRoundKey.(seq.Nr,KeyNr); hence thesis by X2,XREAL_1:8; end; uniqueness proof let s1,s2 be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); 1+0 < 7+m by XREAL_1:8; then 0 < 7+m-1 by XREAL_1:50; then 7+m-1 in NAT by INT_1:3; then reconsider Nr = 7+m-1 as Nat; assume A1: ex seq be FinSequence of (4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN))) st len seq = 7+m-1 & (ex Keyi1 be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st Keyi1 = (Rev((KeyExpansion(SBT,m)).(Key))).1 & seq.1 = (InvSubBytes(SBT)*InvShiftRows).(AddRoundKey.(text,Keyi1))) & (for i be Nat st 1 <= i & i < 7+m-1 holds ex Keyi be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st Keyi = (Rev((KeyExpansion(SBT,m)).(Key))).(i+1) & seq.(i+1) = (InvSubBytes(SBT)*InvShiftRows*(MCFunc")).(AddRoundKey.(seq.i,Keyi))) & ex KeyNr be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st KeyNr = (Rev((KeyExpansion(SBT,m)).(Key))).(7+m) & s1 = AddRoundKey.(seq.(7+m-1),KeyNr); assume A2: ex seq be FinSequence of (4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN))) st len seq = 7+m-1 & (ex Keyi1 be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st Keyi1 = (Rev((KeyExpansion(SBT,m)).(Key))).1 & seq.1 = (InvSubBytes(SBT)*InvShiftRows).(AddRoundKey.(text,Keyi1))) & (for i be Nat st 1 <= i & i < 7+m-1 holds ex Keyi be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st Keyi = (Rev((KeyExpansion(SBT,m)).(Key))).(i+1) & seq.(i+1) = (InvSubBytes(SBT)*InvShiftRows*(MCFunc")).(AddRoundKey.(seq.i,Keyi))) & ex KeyNr be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st KeyNr = (Rev((KeyExpansion(SBT,m)).(Key))).(7+m) & s2 = AddRoundKey.(seq.(7+m-1),KeyNr); consider seq1 be FinSequence of (4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN))) such that P1: len seq1 = Nr & (ex Keyi1 be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st Keyi1 = (Rev((KeyExpansion(SBT,m)).(Key))).1 & seq1.1 = (InvSubBytes(SBT)*InvShiftRows).(AddRoundKey.(text,Keyi1))) & (for i be Nat st 1 <= i & i < Nr holds ex Keyi be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st Keyi = (Rev((KeyExpansion(SBT,m)).(Key))).(i+1) & seq1.(i+1) = (InvSubBytes(SBT)*InvShiftRows*(MCFunc")).(AddRoundKey.(seq1.i,Keyi))) & ex KeyNr be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st KeyNr = (Rev((KeyExpansion(SBT,m)).(Key))).(7+m) & s1 = AddRoundKey.(seq1.(7+m-1),KeyNr) by A1; consider seq2 be FinSequence of (4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN))) such that P2: len seq2 = Nr & (ex Keyi1 be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st Keyi1 = (Rev((KeyExpansion(SBT,m)).(Key))).1 & seq2.1 = (InvSubBytes(SBT)*InvShiftRows).(AddRoundKey.(text,Keyi1))) & (for i be Nat st 1 <= i & i < Nr holds ex Keyi be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st Keyi = (Rev((KeyExpansion(SBT,m)).(Key))).(i+1) & seq2.(i+1) = (InvSubBytes(SBT)*InvShiftRows*(MCFunc")).(AddRoundKey.(seq2.i,Keyi))) & ex KeyNr be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st KeyNr = (Rev((KeyExpansion(SBT,m)).(Key))).(7+m) & s2 = AddRoundKey.(seq2.(7+m-1),KeyNr) by A2; defpred EQ[Nat] means 1 <= $1 & $1 <= len seq1 implies seq1.$1 = seq2.$1; Q50: EQ[0]; Q51: for i be Nat st EQ[i] holds EQ[i+1] proof let i be Nat; assume Q52: EQ[i]; assume 1 <= i+1 & i+1 <= len seq1; then Q54: 1-1 <= i+1-1 & i+1-1 <= (len seq1)-1 by XREAL_1:9; Q550: (len seq1)-1 <= (len seq1)-0 by XREAL_1:13; per cases; suppose C1: i = 0; thus seq1.(i+1) = seq2.(i+1) by C1,P1,P2; end; suppose Q560: i <> 0; Nr-1 < Nr-0 by XREAL_1:15; then XX1: 1 <= i & i < Nr by Q560,NAT_1:14,P1,Q54,XXREAL_0:2; then Q60: ex Keyi be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st Keyi = (Rev((KeyExpansion(SBT,m)).(Key))).(i+1) & seq1.(i+1) = (InvSubBytes(SBT)*InvShiftRows*(MCFunc")).(AddRoundKey.(seq1.i,Keyi)) by P1; ex Keyi be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st Keyi = (Rev((KeyExpansion(SBT,m)).(Key))).(i+1) & seq2.(i+1) = (InvSubBytes(SBT)*InvShiftRows*(MCFunc")).(AddRoundKey.(seq2.i,Keyi)) by P2,XX1; hence seq1.(i+1) = seq2.(i+1) by Q560,NAT_1:14,Q550,Q54,XXREAL_0:2,Q52,Q60; end; end; for i be Nat holds EQ[i] from NAT_1:sch 2(Q50,Q51); hence s1 = s2 by FINSEQ_1:14,P1,P2; end; end; theorem INV01: for input be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds (MCFunc").(MCFunc.input) = input proof let input be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); thus (MCFunc").(MCFunc.(input)) = ((MCFunc")*MCFunc).input by FUNCT_2:15 .= (id (4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)))).input by FUNCT_2:61 .= input; end; theorem for output be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds MCFunc.((MCFunc").output) = output proof let output be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); thus (MCFunc).((MCFunc").(output)) = (MCFunc*(MCFunc")).output by FUNCT_2:15 .= (id (4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)))).output by FUNCT_2:61 .= output; end; theorem LAST01: for m be Nat, text be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds (InvSubBytes(SBT)*InvShiftRows).((ShiftRows*SubBytes(SBT)).text) = text proof let m be Nat, text be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); thus (InvSubBytes(SBT)*InvShiftRows).((ShiftRows*SubBytes(SBT)).text) = (InvSubBytes(SBT)*InvShiftRows).(ShiftRows.((SubBytes(SBT)).text)) by FUNCT_2:15 .= (InvSubBytes(SBT)).(InvShiftRows.(ShiftRows.((SubBytes(SBT)).text))) by FUNCT_2:15 .= (InvSubBytes(SBT)). ((SubBytes(SBT)).text) by INV04 .= text by INV07; end; theorem LAST02: for m be Nat, text be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) holds (InvSubBytes(SBT)*InvShiftRows*(MCFunc")). ((MCFunc*ShiftRows*SubBytes(SBT)).text) = text proof let m be Nat, text be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); thus (InvSubBytes(SBT)*InvShiftRows*(MCFunc")). ((MCFunc*ShiftRows*SubBytes(SBT)).text) = (InvSubBytes(SBT)*InvShiftRows*(MCFunc")). ((MCFunc*ShiftRows).((SubBytes(SBT)).text)) by FUNCT_2:15 .= (InvSubBytes(SBT)*InvShiftRows*(MCFunc")). (MCFunc.(ShiftRows.((SubBytes(SBT)).text))) by FUNCT_2:15 .= (InvSubBytes(SBT)*InvShiftRows).((MCFunc"). (MCFunc.(ShiftRows.((SubBytes(SBT)).text)))) by FUNCT_2:15 .= (InvSubBytes(SBT)*InvShiftRows).(ShiftRows.((SubBytes(SBT)).text)) by INV01 .= (InvSubBytes(SBT)).(InvShiftRows.(ShiftRows.((SubBytes(SBT)).text))) by FUNCT_2:15 .= (InvSubBytes(SBT)).((SubBytes(SBT)).text) by INV04 .= text by INV07; end; theorem LAST03: for m be Nat, text be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), Key be Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), dkeyi,ekeyi be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st (m = 4 or m = 6 or m = 8) & dkeyi = (Rev((KeyExpansion(SBT,m)).(Key))).1 & ekeyi = ((KeyExpansion(SBT,m)).(Key)).(7+m) holds AddRoundKey.(AddRoundKey.(text,ekeyi),dkeyi) = text proof let m be Nat, text be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), key be Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), dkeyi,ekeyi be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); assume AS: (m = 4 or m = 6 or m = 8) & dkeyi = (Rev((KeyExpansion(SBT,m)).(key))).1 & ekeyi = ((KeyExpansion(SBT,m)).(key)).(7+m); set p = (KeyExpansion(SBT,m)).(key); (KeyExpansion(SBT,m)).(key) in (7+m)-tuples_on(4-tuples_on (4-tuples_on (8-tuples_on BOOLEAN))); then B0: ex s be Element of (4-tuples_on (4-tuples_on (8-tuples_on BOOLEAN)))* st (KeyExpansion(SBT,m)).(key) = s & len s = (7+m); 1+0 < 7+m by XREAL_1:8; then 1 in Seg (7+m); then B1: 1 in dom p by FINSEQ_1:def 3,B0; A0: dkeyi = p.((len p)-1+1) by AS,FINSEQ_5:58,B1 .= ekeyi by B0,AS; now let i,j be Nat; assume A3: i in Seg 4 & j in Seg 4; then consider etextij,ekeyij be Element of 8-tuples_on BOOLEAN such that A4: etextij = (text.i).j & ekeyij = (ekeyi.i).j & ((AddRoundKey.(text,ekeyi)).i).j = Op-XOR(etextij,ekeyij) by DefAddRoundKey; consider dtextij,dkeyij be Element of 8-tuples_on BOOLEAN such that A5: dtextij = ((AddRoundKey.(text,ekeyi)).i).j & dkeyij = (dkeyi.i).j & ((AddRoundKey.(AddRoundKey.(text,ekeyi),dkeyi)).i).j = Op-XOR(dtextij,dkeyij) by DefAddRoundKey,A3; thus ((AddRoundKey.(AddRoundKey.(text,ekeyi),dkeyi)).i).j = (text.i).j by A4,A5,A0,DESCIP_1:17; end; hence AddRoundKey.(AddRoundKey.(text,ekeyi),dkeyi) = text by LM01; end; LAST04: for m be Nat, text,otext be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), Key be Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), Keyi1,KeyNr be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st (m = 4 or m = 6 or m = 8) & Keyi1 = (Rev((KeyExpansion(SBT,m)).(Key))).1 & KeyNr = ((KeyExpansion(SBT,m)).(Key)).(7+m) & otext = AddRoundKey.((ShiftRows*SubBytes(SBT)).text,KeyNr) holds (InvSubBytes(SBT)*InvShiftRows).(AddRoundKey.(otext,Keyi1)) = text proof let m be Nat, text,otext be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), Key be Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), Keyi1,KeyNr be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); assume AS: (m = 4 or m = 6 or m = 8) & Keyi1 = (Rev((KeyExpansion(SBT,m)).(Key))).1 & KeyNr = ((KeyExpansion(SBT,m)).(Key)).(7+m) & otext = AddRoundKey.((ShiftRows*SubBytes(SBT)).text,KeyNr); (AddRoundKey.(otext,Keyi1)) = (ShiftRows*SubBytes(SBT)).text by AS,LAST03; hence (InvSubBytes(SBT)*InvShiftRows).(AddRoundKey. (otext,Keyi1)) = text by LAST01; end; theorem LAST05: for m be Nat, text be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), key be Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), dkeyi,ekeyi be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st (m = 4 or m = 6 or m = 8) & dkeyi = ((KeyExpansion(SBT,m)).(key)).1 & ekeyi = (Rev((KeyExpansion(SBT,m)).(key))).(7+m) holds AddRoundKey.(AddRoundKey.(text,ekeyi),dkeyi) = text proof let m be Nat, text be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), key be Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), dkeyi,ekeyi be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); assume AS: (m = 4 or m = 6 or m = 8) & dkeyi = ((KeyExpansion(SBT,m)).(key)).1 & ekeyi = (Rev((KeyExpansion(SBT,m)).(key))).(7+m); set p = (KeyExpansion(SBT,m)).(key); (KeyExpansion(SBT,m)).(key) in (7+m)-tuples_on(4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN))); then B0: ex s be Element of (4-tuples_on (4-tuples_on (8-tuples_on BOOLEAN)))* st (KeyExpansion(SBT,m)).(key) = s & len s = (7+m); 1+0 < 7+m by XREAL_1:8; then 7+m in Seg (7+m); then B1: 7+m in dom p by FINSEQ_1:def 3,B0; A0: ekeyi = p.((len p)-(7+m)+1) by AS,FINSEQ_5:58,B1 .= dkeyi by B0,AS; now let i,j be Nat; assume A3: i in Seg 4 & j in Seg 4; then consider etextij,ekeyij be Element of 8-tuples_on BOOLEAN such that A4: etextij = (text.i).j & ekeyij = (ekeyi.i).j & ((AddRoundKey.(text,ekeyi)).i).j = Op-XOR(etextij,ekeyij) by DefAddRoundKey; consider dtextij,dkeyij be Element of 8-tuples_on BOOLEAN such that A5: dtextij = ((AddRoundKey.(text,ekeyi)).i).j & dkeyij = (dkeyi.i).j & ((AddRoundKey.(AddRoundKey.(text,ekeyi),dkeyi)).i).j = Op-XOR(dtextij,dkeyij) by DefAddRoundKey,A3; thus ((AddRoundKey.(AddRoundKey.(text,ekeyi),dkeyi)).i).j = (text.i).j by A4,A5,A0,DESCIP_1:17; end; hence AddRoundKey.(AddRoundKey.(text,ekeyi),dkeyi) = text by LM01; end; theorem for m be Nat, text,otext be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), Key be Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), Keyi1,KeyNr be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st (m = 4 or m = 6 or m = 8) & Keyi1 = ((KeyExpansion(SBT,m)).(Key)).1 & KeyNr = (Rev((KeyExpansion(SBT,m)).(Key))).(7+m) & otext = AddRoundKey.((ShiftRows*SubBytes(SBT)).text,KeyNr) holds (InvSubBytes(SBT)*InvShiftRows).(AddRoundKey.(otext,Keyi1)) = text proof let m be Nat, text,otext be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), Key be Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), Keyi1,KeyNr be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); assume AS: (m = 4 or m = 6 or m = 8) & Keyi1 = ((KeyExpansion(SBT,m)).(Key)).1 & KeyNr = (Rev((KeyExpansion(SBT,m)).(Key))).(7+m) & otext = AddRoundKey.((ShiftRows*SubBytes(SBT)).text,KeyNr); (AddRoundKey.(otext,Keyi1)) = (ShiftRows*SubBytes(SBT)).text by AS,LAST05; hence (InvSubBytes(SBT)*InvShiftRows).(AddRoundKey.(otext,Keyi1)) = text by LAST01; end; theorem LAST08: for m,i be Nat, text be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), Key be Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), eKeyi,dKeyi be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st (m = 4 or m = 6 or m = 8) & i <= 7+m-1 & eKeyi = ((KeyExpansion(SBT,m)).(Key)).(7+m-i) & dKeyi = (Rev((KeyExpansion(SBT,m)).(Key))).(i+1) holds AddRoundKey.(AddRoundKey.(text,eKeyi),dKeyi) = text proof let m,i be Nat, text be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), key be Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), ekeyi,dkeyi be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); assume AS: (m = 4 or m = 6 or m = 8) & i <= 7+m-1 & ekeyi = ((KeyExpansion(SBT,m)).(key)).(7+m-i) & dkeyi = (Rev((KeyExpansion(SBT,m)).(key))).(i+1); set p = (KeyExpansion(SBT,m)).(key); (KeyExpansion(SBT,m)).(key) in (7+m)-tuples_on(4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN))); then B0: ex s be Element of (4-tuples_on (4-tuples_on (8-tuples_on BOOLEAN)))* st (KeyExpansion(SBT,m)).(key) = s & len s = (7+m); i+1 <= 7+m-1+1 by AS,XREAL_1:7; then 1 <= i+1 & i+1 <= 7+m by NAT_1:11; then i+1 in Seg (7+m); then B1: i+1 in dom p by FINSEQ_1:def 3,B0; A0: dkeyi = p.((len p)-(i+1)+1) by AS,FINSEQ_5:58,B1 .= ekeyi by B0,AS; now let i,j be Nat; assume A3: i in Seg 4 & j in Seg 4; then consider etextij,ekeyij be Element of 8-tuples_on BOOLEAN such that A4: etextij = (text.i).j & ekeyij = (ekeyi.i).j & ((AddRoundKey.(text,ekeyi)).i).j = Op-XOR(etextij,ekeyij) by DefAddRoundKey; consider dtextij,dkeyij be Element of 8-tuples_on BOOLEAN such that A5: dtextij = ((AddRoundKey.(text,ekeyi)).i).j & dkeyij = (dkeyi.i).j & ((AddRoundKey.(AddRoundKey.(text,ekeyi),dkeyi)).i).j = Op-XOR(dtextij,dkeyij) by DefAddRoundKey,A3; thus ((AddRoundKey.(AddRoundKey.(text,ekeyi),dkeyi)).i).j = (text.i).j by A4,A5,A0,DESCIP_1:17; end; hence AddRoundKey.(AddRoundKey.(text,ekeyi),dkeyi) = text by LM01; end; LAST07: for m be Nat, text be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), Key be Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), eKeyi,dKeyi be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st (m = 4 or m = 6 or m = 8) & eKeyi = ((KeyExpansion(SBT,m)).(Key)).1 & dKeyi = (Rev((KeyExpansion(SBT,m)).(Key))).(7+m) holds AddRoundKey.(AddRoundKey.(text,eKeyi),dKeyi) = text proof let m be Nat, text be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), Key be Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), eKeyi,dKeyi be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); assume AS: (m = 4 or m = 6 or m = 8) & eKeyi = ((KeyExpansion(SBT,m)).(Key)).1 & dKeyi = (Rev((KeyExpansion(SBT,m)).(Key))).(7+m); 1+0 < 7+m by XREAL_1:8; then 0 < 7+m-1 by XREAL_1:50; then 7+m-1 in NAT by INT_1:3; then reconsider i = 7+m-1 as Nat; P2: eKeyi = ((KeyExpansion(SBT,m)).(Key)).(7+m-i) by AS; dKeyi = (Rev((KeyExpansion(SBT,m)).(Key))).(i+1) by AS; hence thesis by AS,P2,LAST08; end; theorem LASTXX: for m be Nat, text be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), Key be Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st (m = 4 or m = 6 or m = 8) holds AES-DEC(SBT,MCFunc,AES-ENC(SBT,MCFunc,text,Key),Key) = text proof let m be Nat; let text be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); let Key be Element of m-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); 1+0 < 7+m by XREAL_1:8; then N1: 0 < 7+m-1 by XREAL_1:50; then 7+m-1 in NAT by INT_1:3; then reconsider Nr = 7+m-1 as Nat; A0: 1 <= Nr by NAT_1:14,N1; assume AS: (m = 4 or m = 6 or m = 8); consider eseq be FinSequence of (4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN))) such that P1: len eseq = Nr & (ex Keyi1 be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st Keyi1 = ((KeyExpansion(SBT,m)).(Key)).1 & eseq.1 = AddRoundKey.(text,Keyi1)) & (for i be Nat st 1 <= i & i < Nr holds ex Keyi be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st Keyi = ((KeyExpansion(SBT,m)).(Key)).(i+1) & eseq.(i+1) = AddRoundKey.((MCFunc*ShiftRows*SubBytes(SBT)).(eseq.i),Keyi)) & ex KeyNr be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st KeyNr = ((KeyExpansion(SBT,m)).(Key)).(7+m) & AES-ENC(SBT,MCFunc,text,Key) = AddRoundKey.((ShiftRows*SubBytes(SBT)).(eseq.Nr),KeyNr) by defENC; consider dseq be FinSequence of (4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN))) such that P2: len dseq = Nr & (ex Keyi1 be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st Keyi1 = (Rev((KeyExpansion(SBT,m)).(Key))).1 & dseq.1 = (InvSubBytes(SBT)*InvShiftRows). (AddRoundKey.(AES-ENC(SBT,MCFunc,text,Key),Keyi1))) & (for i be Nat st 1 <= i & i < Nr holds ex Keyi be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st Keyi = (Rev((KeyExpansion(SBT,m)).(Key))).(i+1) & dseq.(i+1) = (InvSubBytes(SBT)*InvShiftRows*(MCFunc")).(AddRoundKey.(dseq.i,Keyi))) & ex KeyNr be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) st KeyNr = (Rev((KeyExpansion(SBT,m)).(Key))).(7+m) & AES-DEC(SBT,MCFunc,AES-ENC(SBT,MCFunc,text,Key),Key) = AddRoundKey.(dseq.Nr,KeyNr) by defDEC; consider eKeyi1 be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) such that P11: eKeyi1 = ((KeyExpansion(SBT,m)).(Key)).1 & eseq.1 = AddRoundKey.(text,eKeyi1) by P1; consider eKeyNr be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) such that P12: eKeyNr = ((KeyExpansion(SBT,m)).(Key)).(7+m) & AES-ENC(SBT,MCFunc,text,Key) = AddRoundKey.((ShiftRows*SubBytes(SBT)).(eseq.Nr),eKeyNr) by P1; consider dKeyi1 be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) such that P21: dKeyi1 = (Rev((KeyExpansion(SBT,m)).(Key))).1 & dseq.1 = (InvSubBytes(SBT)*InvShiftRows). (AddRoundKey.(AES-ENC(SBT,MCFunc,text,Key),dKeyi1)) by P2; consider dKeyNr be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) such that P22: dKeyNr = (Rev((KeyExpansion(SBT,m)).(Key))).(7+m) & AES-DEC(SBT,MCFunc,AES-ENC(SBT,MCFunc,text,Key),Key) = AddRoundKey.(dseq.Nr,dKeyNr) by P2; defpred PQ[Nat] means $1 < Nr implies dseq.($1+1) = eseq.(Nr-$1); Nr in Seg Nr by A0; then Nr in dom eseq by P1,FINSEQ_1:def 3; then eseq.Nr in rng eseq by FUNCT_1:3; then reconsider esqm = eseq.Nr as Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); dseq.(1+0) = esqm by P12,P21,AS,LAST04 .= eseq.(Nr-0); then PN1: PQ[0]; PN2: for i be Nat st PQ[i] holds PQ[i+1] proof let i be Nat; assume A1: PQ[i]; assume A2: i+1 < Nr; A4: i <= i+1 by NAT_1:11; consider dKeyi be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) such that A6: dKeyi = (Rev((KeyExpansion(SBT,m)).(Key))).((i+1)+1) & dseq.((i+1)+1) = (InvSubBytes(SBT)*InvShiftRows*(MCFunc")).(AddRoundKey.(dseq.(i+1),dKeyi)) by P2,A2,NAT_1:11; X11: 0 < Nr-(i+1) by A2,XREAL_1:50; then Nr-(i+1) in NAT by INT_1:3; then reconsider m7i1 = Nr-(i+1) as Nat; 1 <= m7i1 by NAT_1:14,X11; then A9: 1 <= Nr-(i+1) & Nr-(i+1) < Nr by XREAL_1:44; consider eKeyi be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) such that A10: eKeyi = ((KeyExpansion(SBT,m)).(Key)).(m7i1+1) & eseq.(m7i1+1) = AddRoundKey.((MCFunc*ShiftRows*SubBytes(SBT)).(eseq.(m7i1)),eKeyi) by P1,A9; m7i1 in Seg Nr by A9; then m7i1 in dom eseq by P1,FINSEQ_1:def 3; then eseq.m7i1 in rng eseq by FUNCT_1:3; then reconsider esq7mi1 = eseq.m7i1 as Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); reconsider MSSesq7mi1 = (MCFunc*ShiftRows*SubBytes(SBT)).esq7mi1 as Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); XXX: eKeyi = ((KeyExpansion(SBT,m)).(Key)).(7+m-(i+1)) by A10; A12: AddRoundKey.(eseq.(Nr-i),dKeyi) = MSSesq7mi1 by A10,A2,AS,A6,XXX,LAST08; thus dseq.((i+1)+1) = eseq.(Nr-(i+1)) by A6,A4,A2,XXREAL_0:2,A1,A12,LAST02; end; P30: for k be Nat holds PQ[k] from NAT_1:sch 2(PN1,PN2); 5+m < 6+m by XREAL_1:8; then P31: dseq.(5+m+1) = eseq.(Nr-(5+m)) by P30; 1 <= 1 & 1 <= 1+(5+m) by NAT_1:11; then 1 in Seg Nr; then 1 in dom eseq by P1,FINSEQ_1:def 3; then eseq.1 in rng eseq by FUNCT_1:3; then reconsider esq1 = eseq.1 as Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); thus AES-DEC(SBT,MCFunc,AES-ENC(SBT,MCFunc,text,Key),Key) = text by P22,P31,P11,AS,LAST07; end; theorem LR8D1: for D be non empty set, n,m be non zero Element of NAT, r be Element of n-tuples_on D st m <= n & 8 <= n-m holds Op-Left(Op-Right(r,m),8) is Element of 8-tuples_on D proof let D be non empty set, n,m be non zero Element of NAT, r be Element of n-tuples_on D; assume A1: m <= n & 8 <= n-m; r in { s where s is Element of D*: len s = n}; then consider s be Element of D* such that A2: r = s & len s = n; len Op-Right(r,m) = n - m by A1,A2,RFINSEQ:def 1; then len(Op-Left(Op-Right(r,m),8)) = 8 by A1,FINSEQ_1:59; hence thesis by FINSEQ_2:92; end; Lm1: for D be non empty set, n be non zero Element of NAT, r be Element of n-tuples_on D st 8 <= n & 8 <= n-8 & 16 <= n & 8 <= n-16 & 24 <= n & 8 <= n-24 holds <* Op-Left(r,8),Op-Left(Op-Right(r,8),8),Op-Left(Op-Right(r,16),8), Op-Left(Op-Right(r,24),8) *> is Element of 4-tuples_on (8-tuples_on D) proof let D be non empty set, n be non zero Element of NAT, r be Element of n-tuples_on D; assume 8 <= n & 8 <= n-8 & 16 <= n & 8 <= n-16 & 24 <= n & 8 <= n-24; then Op-Left(r,8) is Element of 8-tuples_on D & Op-Left(Op-Right(r,8),8) is Element of 8-tuples_on D & Op-Left(Op-Right(r,16),8) is Element of 8-tuples_on D & Op-Left(Op-Right(r,24),8) is Element of 8-tuples_on D by DESCIP_1:1,LR8D1; hence thesis by LMGSEQ4; end; Lm2: for D be non empty set, n,m,l,p,q be non zero Element of NAT, r be Element of n-tuples_on D st m <= n & 8 <= n-m & l = m+8 & l <= n & 8 <= n-l & p = m+16 & p <= n & 8 <= n-p & q = m+24 & q <= n & 8 <= n-q holds <* Op-Left(Op-Right(r,m),8),Op-Left(Op-Right(r,l),8), Op-Left(Op-Right(r,p),8),Op-Left(Op-Right(r,q),8) *> is Element of 4-tuples_on (8-tuples_on D) proof let D be non empty set, n,m,l,p,q be non zero Element of NAT, r be Element of n-tuples_on D; assume m <= n & 8 <= n-m & l = m+8 & l <= n & 8 <= n-l & p = m+16 & p <= n & 8 <= n-p & q = m+24 & q <= n & 8 <= n-q; then Op-Left(Op-Right(r,m),8) is Element of 8-tuples_on D & Op-Left(Op-Right(r,l),8) is Element of 8-tuples_on D & Op-Left(Op-Right(r,p),8) is Element of 8-tuples_on D & Op-Left(Op-Right(r,q),8) is Element of 8-tuples_on D by LR8D1; hence thesis by LMGSEQ4; end; Lm3: for D be non empty set, n,m,l,p,q be non zero Element of NAT, r be Element of n-tuples_on D st m <= n & 8 <= n-m & l = m+8 & l <= n & 8 <= n-l & p = m+16 & p <= n & 8 <= n-p & q = m+24 & q <= n & 8 = n-q holds <* Op-Left(Op-Right(r,m),8),Op-Left(Op-Right(r,l),8), Op-Left(Op-Right(r,p),8),Op-Right(r,q) *> is Element of 4-tuples_on (8-tuples_on D) proof let D be non empty set, n,m,l,p,q be non zero Element of NAT, r be Element of n-tuples_on D; assume m <= n & 8 <= n-m & l = m+8 & l <= n & 8 <= n-l & p = m+16 & p <= n & 8 <= n-p & q = m+24 & q <= n & 8 = n-q; then Op-Left(Op-Right(r,m),8) is Element of 8-tuples_on D & Op-Left(Op-Right(r,l),8) is Element of 8-tuples_on D & Op-Left(Op-Right(r,p),8) is Element of 8-tuples_on D & Op-Right(r,q) is Element of 8-tuples_on D by DESCIP_1:2,LR8D1; hence thesis by LMGSEQ4; end; definition let r be Element of 128-tuples_on BOOLEAN; func AES-KeyInitState128(r) -> Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) means it.1 = <* Op-Left(r,8),Op-Left(Op-Right(r,8),8), Op-Left(Op-Right(r,16),8),Op-Left(Op-Right(r,24),8) *> & it.2 = <* Op-Left(Op-Right(r,32),8),Op-Left(Op-Right(r,40),8), Op-Left(Op-Right(r,48),8),Op-Left(Op-Right(r,56),8) *> & it.3 = <* Op-Left(Op-Right(r,64),8),Op-Left(Op-Right(r,72),8), Op-Left(Op-Right(r,80),8),Op-Left(Op-Right(r,88),8) *> & it.4 = <* Op-Left(Op-Right(r,96),8),Op-Left(Op-Right(r,104),8), Op-Left(Op-Right(r,112),8),Op-Right(r,120) *>; existence proof set R1 = <* Op-Left(r,8),Op-Left(Op-Right(r,8),8), Op-Left(Op-Right(r,16),8),Op-Left(Op-Right(r,24),8) *>; set R2 = <* Op-Left(Op-Right(r,32),8),Op-Left(Op-Right(r,40),8), Op-Left(Op-Right(r,48),8),Op-Left(Op-Right(r,56),8) *>; set R3 = <* Op-Left(Op-Right(r,64),8),Op-Left(Op-Right(r,72),8), Op-Left(Op-Right(r,80),8),Op-Left(Op-Right(r,88),8) *>; set R4 = <* Op-Left(Op-Right(r,96),8),Op-Left(Op-Right(r,104),8), Op-Left(Op-Right(r,112),8),Op-Right(r,120) *>; 8 <= 128-8 & 8 <= 128-16 & 8 <= 128-24; then reconsider R1 as Element of 4-tuples_on (8-tuples_on BOOLEAN) by Lm1; 8 <= 128-32 & 8 <= 128-40 & 8 <= 128-48 & 8 <= 128-56 & 40 = 32+8 & 48 = 32+16 & 56 = 32+24; then reconsider R2 as Element of 4-tuples_on (8-tuples_on BOOLEAN) by Lm2; 8 <= 128-64 & 8 <= 128-72 & 8 <= 128-80 & 8 <= 128-88 & 72 = 64+8 & 80 = 64+16 & 88 = 64+24; then reconsider R3 as Element of 4-tuples_on (8-tuples_on BOOLEAN) by Lm2; 8 <= 128-96 & 8 <= 128-104 & 8 <= 128-112 & 8 = 128-120 & 104 = 96+8 & 112 = 96+16 & 120 = 96+24 & 8 = 128-120; then reconsider R4 as Element of 4-tuples_on (8-tuples_on BOOLEAN) by Lm3; set T1 = <*R1,R2*>; set T2 = <*R3,R4*>; set T = T1^T2; A4: T.1 = T1.1 & ... & T.2 = T1.2 by FINSEQ_3:154; A5: T.(2+1) = T2.1 & ... & T.(2+2) = T2.2 by FINSEQ_3:155; len T = 4 & T is FinSequence of 4-tuples_on (8-tuples_on BOOLEAN) by CARD_1:def 7; then reconsider T as Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) by FINSEQ_2:92; take T; thus thesis by A4,A5,FINSEQ_1:44; end; uniqueness proof let p,q be Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); assume A6: p.1 = <* Op-Left(r,8),Op-Left(Op-Right(r,8),8), Op-Left(Op-Right(r,16),8),Op-Left(Op-Right(r,24),8) *> & p.2 = <* Op-Left(Op-Right(r,32),8),Op-Left(Op-Right(r,40),8), Op-Left(Op-Right(r,48),8),Op-Left(Op-Right(r,56),8) *> & p.3 = <* Op-Left(Op-Right(r,64),8),Op-Left(Op-Right(r,72),8), Op-Left(Op-Right(r,80),8),Op-Left(Op-Right(r,88),8) *> & p.4 = <* Op-Left(Op-Right(r,96),8),Op-Left(Op-Right(r,104),8), Op-Left(Op-Right(r,112),8),Op-Right(r,120) *>; assume A7: q.1 = <* Op-Left(r,8),Op-Left(Op-Right(r,8),8), Op-Left(Op-Right(r,16),8),Op-Left(Op-Right(r,24),8) *> & q.2 = <* Op-Left(Op-Right(r,32),8),Op-Left(Op-Right(r,40),8), Op-Left(Op-Right(r,48),8),Op-Left(Op-Right(r,56),8) *> & q.3 = <* Op-Left(Op-Right(r,64),8),Op-Left(Op-Right(r,72),8), Op-Left(Op-Right(r,80),8),Op-Left(Op-Right(r,88),8) *> & q.4 = <* Op-Left(Op-Right(r,96),8),Op-Left(Op-Right(r,104),8), Op-Left(Op-Right(r,112),8),Op-Right(r,120) *>; p in 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); then A8: ex v be Element of (4-tuples_on (8-tuples_on BOOLEAN))* st p = v & len v = 4; q in 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); then A9: ex v be Element of (4-tuples_on (8-tuples_on BOOLEAN))* st q = v & len v = 4; for i be Nat st 1 <= i & i <= len p holds p.i = q.i proof let i be Nat; assume 1 <= i & i <= len p; then i = 1 or ... or i = 4 by A8; hence thesis by A6,A7; end; hence p = q by A8,A9,FINSEQ_1:14; end; end; definition let r be Element of 192-tuples_on BOOLEAN; func AES-KeyInitState192(r) -> Element of 6-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) means it.1 = <* Op-Left(r,8),Op-Left(Op-Right(r,8),8), Op-Left(Op-Right(r,16),8),Op-Left(Op-Right(r,24),8) *> & it.2 = <* Op-Left(Op-Right(r,32),8),Op-Left(Op-Right(r,40),8), Op-Left(Op-Right(r,48),8),Op-Left(Op-Right(r,56),8) *> & it.3 = <* Op-Left(Op-Right(r,64),8),Op-Left(Op-Right(r,72),8), Op-Left(Op-Right(r,80),8),Op-Left(Op-Right(r,88),8) *> & it.4 = <* Op-Left(Op-Right(r,96),8),Op-Left(Op-Right(r,104),8), Op-Left(Op-Right(r,112),8),Op-Left(Op-Right(r,120),8) *> & it.5 = <* Op-Left(Op-Right(r,128),8),Op-Left(Op-Right(r,136),8), Op-Left(Op-Right(r,144),8),Op-Left(Op-Right(r,152),8) *> & it.6 = <* Op-Left(Op-Right(r,160),8),Op-Left(Op-Right(r,168),8), Op-Left(Op-Right(r,176),8),Op-Right(r,184) *>; existence proof set R1 = <* Op-Left(r,8),Op-Left(Op-Right(r,8),8), Op-Left(Op-Right(r,16),8),Op-Left(Op-Right(r,24),8) *>; set R2 = <* Op-Left(Op-Right(r,32),8),Op-Left(Op-Right(r,40),8), Op-Left(Op-Right(r,48),8),Op-Left(Op-Right(r,56),8) *>; set R3 = <* Op-Left(Op-Right(r,64),8),Op-Left(Op-Right(r,72),8), Op-Left(Op-Right(r,80),8),Op-Left(Op-Right(r,88),8) *>; set R4 = <* Op-Left(Op-Right(r,96),8),Op-Left(Op-Right(r,104),8), Op-Left(Op-Right(r,112),8),Op-Left(Op-Right(r,120),8) *>; set R5 = <* Op-Left(Op-Right(r,128),8),Op-Left(Op-Right(r,136),8), Op-Left(Op-Right(r,144),8),Op-Left(Op-Right(r,152),8) *>; set R6 = <* Op-Left(Op-Right(r,160),8),Op-Left(Op-Right(r,168),8), Op-Left(Op-Right(r,176),8),Op-Right(r,184) *>; 8 <= 192-8 & 8 <= 192-16 & 8 <= 192-24; then reconsider R1 as Element of 4-tuples_on (8-tuples_on BOOLEAN) by Lm1; 8 <= 192-32 & 8 <= 192-40 & 8 <= 192-48 & 8 <= 192-56 & 40 = 32+8 & 48 = 32+16 & 56 = 32+24; then reconsider R2 as Element of 4-tuples_on (8-tuples_on BOOLEAN) by Lm2; 8 <= 192-64 & 8 <= 192-72 & 8 <= 192-80 & 8 <= 192-88 & 72 = 64+8 & 80 = 64+16 & 88 = 64+24; then reconsider R3 as Element of 4-tuples_on (8-tuples_on BOOLEAN) by Lm2; 8 <= 192-96 & 8 <= 192-104 & 8 <= 192-112 & 8 <= 192-120 & 104 = 96+8 & 112 = 96+16 & 120 = 96+24; then reconsider R4 as Element of 4-tuples_on (8-tuples_on BOOLEAN) by Lm2; 8 <= 192-128 & 8 <= 192-136 & 8 <= 192-144 & 8 <= 192-152 & 136 = 128+8 & 144 = 128+16 & 152 = 128+24; then reconsider R5 as Element of 4-tuples_on (8-tuples_on BOOLEAN) by Lm2; 8 <= 192-160 & 8 <= 192-168 & 8 <= 192-176 & 8 = 192-184 & 168 = 160+8 & 176 = 160+16 & 184 = 160+24 & 8 = 192-184; then reconsider R6 as Element of 4-tuples_on (8-tuples_on BOOLEAN) by Lm3; set T1 = <*R1,R2,R3*>; set T2 = <*R4,R5,R6*>; set T = T1^T2; A4: T.1 = T1.1 & ... & T.3 = T1.3 by FINSEQ_3:154; A5: T.(3+1) = T2.1 & ... & T.(3+3) = T2.3 by FINSEQ_3:155; len T = 6 & T is FinSequence of 4-tuples_on (8-tuples_on BOOLEAN) by CARD_1:def 7; then reconsider T as Element of 6-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) by FINSEQ_2:92; take T; thus thesis by A4,A5,FINSEQ_1:45; end; uniqueness proof let p,q be Element of 6-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); assume A6: p.1 = <* Op-Left(r,8),Op-Left(Op-Right(r,8),8), Op-Left(Op-Right(r,16),8),Op-Left(Op-Right(r,24),8) *> & p.2 = <* Op-Left(Op-Right(r,32),8),Op-Left(Op-Right(r,40),8), Op-Left(Op-Right(r,48),8),Op-Left(Op-Right(r,56),8) *> & p.3 = <* Op-Left(Op-Right(r,64),8),Op-Left(Op-Right(r,72),8), Op-Left(Op-Right(r,80),8),Op-Left(Op-Right(r,88),8) *> & p.4 = <* Op-Left(Op-Right(r,96),8),Op-Left(Op-Right(r,104),8), Op-Left(Op-Right(r,112),8),Op-Left(Op-Right(r,120),8) *> & p.5 = <* Op-Left(Op-Right(r,128),8),Op-Left(Op-Right(r,136),8), Op-Left(Op-Right(r,144),8),Op-Left(Op-Right(r,152),8) *> & p.6 = <* Op-Left(Op-Right(r,160),8),Op-Left(Op-Right(r,168),8), Op-Left(Op-Right(r,176),8),Op-Right(r,184) *>; assume A7: q.1 = <* Op-Left(r,8),Op-Left(Op-Right(r,8),8), Op-Left(Op-Right(r,16),8),Op-Left(Op-Right(r,24),8) *> & q.2 = <* Op-Left(Op-Right(r,32),8),Op-Left(Op-Right(r,40),8), Op-Left(Op-Right(r,48),8),Op-Left(Op-Right(r,56),8) *> & q.3 = <* Op-Left(Op-Right(r,64),8),Op-Left(Op-Right(r,72),8), Op-Left(Op-Right(r,80),8),Op-Left(Op-Right(r,88),8) *> & q.4 = <* Op-Left(Op-Right(r,96),8),Op-Left(Op-Right(r,104),8), Op-Left(Op-Right(r,112),8),Op-Left(Op-Right(r,120),8) *> & q.5 = <* Op-Left(Op-Right(r,128),8),Op-Left(Op-Right(r,136),8), Op-Left(Op-Right(r,144),8),Op-Left(Op-Right(r,152),8) *> & q.6 = <* Op-Left(Op-Right(r,160),8),Op-Left(Op-Right(r,168),8), Op-Left(Op-Right(r,176),8),Op-Right(r,184) *>; p in 6-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); then A8: ex v be Element of (4-tuples_on (8-tuples_on BOOLEAN))* st p = v & len v = 6; q in 6-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); then A9: ex v be Element of (4-tuples_on (8-tuples_on BOOLEAN))* st q = v & len v = 6; for i be Nat st 1 <= i & i <= len p holds p.i = q.i proof let i be Nat; assume 1 <= i & i <= len p; then i = 1 or ... or i = 6 by A8; hence thesis by A6,A7; end; hence p = q by A8,A9,FINSEQ_1:14; end; end; definition let r be Element of 256-tuples_on BOOLEAN; func AES-KeyInitState256(r) -> Element of 8-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) means it.1 = <* Op-Left(r,8),Op-Left(Op-Right(r,8),8), Op-Left(Op-Right(r,16),8),Op-Left(Op-Right(r,24),8) *> & it.2 = <* Op-Left(Op-Right(r,32),8),Op-Left(Op-Right(r,40),8), Op-Left(Op-Right(r,48),8),Op-Left(Op-Right(r,56),8) *> & it.3 = <* Op-Left(Op-Right(r,64),8),Op-Left(Op-Right(r,72),8), Op-Left(Op-Right(r,80),8),Op-Left(Op-Right(r,88),8) *> & it.4 = <* Op-Left(Op-Right(r,96),8),Op-Left(Op-Right(r,104),8), Op-Left(Op-Right(r,112),8),Op-Left(Op-Right(r,120),8) *> & it.5 = <* Op-Left(Op-Right(r,128),8),Op-Left(Op-Right(r,136),8), Op-Left(Op-Right(r,144),8),Op-Left(Op-Right(r,152),8) *> & it.6 = <* Op-Left(Op-Right(r,160),8),Op-Left(Op-Right(r,168),8), Op-Left(Op-Right(r,176),8),Op-Left(Op-Right(r,184),8) *> & it.7 = <* Op-Left(Op-Right(r,192),8),Op-Left(Op-Right(r,200),8), Op-Left(Op-Right(r,208),8),Op-Left(Op-Right(r,216),8) *> & it.8 = <* Op-Left(Op-Right(r,224),8),Op-Left(Op-Right(r,232),8), Op-Left(Op-Right(r,240),8),Op-Right(r,248) *>; existence proof set R1 = <* Op-Left(r,8),Op-Left(Op-Right(r,8),8), Op-Left(Op-Right(r,16),8),Op-Left(Op-Right(r,24),8) *>; set R2 = <* Op-Left(Op-Right(r,32),8),Op-Left(Op-Right(r,40),8), Op-Left(Op-Right(r,48),8),Op-Left(Op-Right(r,56),8) *>; set R3 = <* Op-Left(Op-Right(r,64),8),Op-Left(Op-Right(r,72),8), Op-Left(Op-Right(r,80),8),Op-Left(Op-Right(r,88),8) *>; set R4 = <* Op-Left(Op-Right(r,96),8),Op-Left(Op-Right(r,104),8), Op-Left(Op-Right(r,112),8),Op-Left(Op-Right(r,120),8) *>; set R5 = <* Op-Left(Op-Right(r,128),8),Op-Left(Op-Right(r,136),8), Op-Left(Op-Right(r,144),8),Op-Left(Op-Right(r,152),8) *>; set R6 = <* Op-Left(Op-Right(r,160),8),Op-Left(Op-Right(r,168),8), Op-Left(Op-Right(r,176),8),Op-Left(Op-Right(r,184),8) *>; set R7 = <* Op-Left(Op-Right(r,192),8),Op-Left(Op-Right(r,200),8), Op-Left(Op-Right(r,208),8),Op-Left(Op-Right(r,216),8) *>; set R8 = <* Op-Left(Op-Right(r,224),8),Op-Left(Op-Right(r,232),8), Op-Left(Op-Right(r,240),8),Op-Right(r,248) *>; 8 <= 256-8 & 8 <= 256-16 & 8 <= 256-24; then reconsider R1 as Element of 4-tuples_on (8-tuples_on BOOLEAN) by Lm1; 8 <= 256-32 & 8 <= 256-40 & 8 <= 256-48 & 8 <= 256-56 & 40 = 32+8 & 48 = 32+16 & 56 = 32+24; then reconsider R2 as Element of 4-tuples_on (8-tuples_on BOOLEAN) by Lm2; 8 <= 256-64 & 8 <= 256-72 & 8 <= 256-80 & 8 <= 256-88 & 72 = 64+8 & 80 = 64+16 & 88 = 64+24; then reconsider R3 as Element of 4-tuples_on (8-tuples_on BOOLEAN) by Lm2; 8 <= 256-96 & 8 <= 256-104 & 8 <= 256-112 & 8 <= 256-120 & 104 = 96+8 & 112 = 96+16 & 120 = 96+24; then reconsider R4 as Element of 4-tuples_on (8-tuples_on BOOLEAN) by Lm2; 8 <= 256-128 & 8 <= 256-136 & 8 <= 256-144 & 8 <= 256-152 & 136 = 128+8 & 144 = 128+16 & 152 = 128+24; then reconsider R5 as Element of 4-tuples_on (8-tuples_on BOOLEAN) by Lm2; 8 <= 256-160 & 8 <= 256-168 & 8 <= 256-176 & 8 <= 256-184 & 168 = 160+8 & 176 = 160+16 & 184 = 160+24; then reconsider R6 as Element of 4-tuples_on (8-tuples_on BOOLEAN) by Lm2; 8 <= 256-192 & 8 <= 256-200 & 8 <= 256-208 & 8 <= 256-216 & 200 = 192+8 & 208 = 192+16 & 216 = 192+24; then reconsider R7 as Element of 4-tuples_on (8-tuples_on BOOLEAN) by Lm2; 8 <= 256-224 & 8 <= 256-232 & 8 <= 256-240 & 8 = 256-248 & 232 = 224+8 & 240 = 224+16 & 248 = 224+24 & 8 = 256-248; then reconsider R8 as Element of 4-tuples_on (8-tuples_on BOOLEAN) by Lm3; set T1 = <*R1,R2,R3,R4*>; set T2 = <*R5,R6,R7,R8*>; set T = T1^T2; A4: T.1 = T1.1 & ... & T.4 = T1.4 by FINSEQ_3:154; A5: T.(4+1) = T2.1 & ... & T.(4+4) = T2.4 by FINSEQ_3:155; len T = 8 & T is FinSequence of 4-tuples_on (8-tuples_on BOOLEAN) by CARD_1:def 7; then reconsider T as Element of 8-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) by FINSEQ_2:92; take T; thus thesis by A4,A5,FINSEQ_4:76; end; uniqueness proof let p,q be Element of 8-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); assume A6: p.1 = <* Op-Left(r,8),Op-Left(Op-Right(r,8),8), Op-Left(Op-Right(r,16),8),Op-Left(Op-Right(r,24),8) *> & p.2 = <* Op-Left(Op-Right(r,32),8),Op-Left(Op-Right(r,40),8), Op-Left(Op-Right(r,48),8),Op-Left(Op-Right(r,56),8) *> & p.3 = <* Op-Left(Op-Right(r,64),8),Op-Left(Op-Right(r,72),8), Op-Left(Op-Right(r,80),8),Op-Left(Op-Right(r,88),8) *> & p.4 = <* Op-Left(Op-Right(r,96),8),Op-Left(Op-Right(r,104),8), Op-Left(Op-Right(r,112),8),Op-Left(Op-Right(r,120),8) *> & p.5 = <* Op-Left(Op-Right(r,128),8),Op-Left(Op-Right(r,136),8), Op-Left(Op-Right(r,144),8),Op-Left(Op-Right(r,152),8) *> & p.6 = <* Op-Left(Op-Right(r,160),8),Op-Left(Op-Right(r,168),8), Op-Left(Op-Right(r,176),8),Op-Left(Op-Right(r,184),8) *> & p.7 = <* Op-Left(Op-Right(r,192),8),Op-Left(Op-Right(r,200),8), Op-Left(Op-Right(r,208),8),Op-Left(Op-Right(r,216),8) *> & p.8 = <* Op-Left(Op-Right(r,224),8),Op-Left(Op-Right(r,232),8), Op-Left(Op-Right(r,240),8),Op-Right(r,248) *>; assume A7: q.1 = <* Op-Left(r,8),Op-Left(Op-Right(r,8),8), Op-Left(Op-Right(r,16),8),Op-Left(Op-Right(r,24),8) *> & q.2 = <* Op-Left(Op-Right(r,32),8),Op-Left(Op-Right(r,40),8), Op-Left(Op-Right(r,48),8),Op-Left(Op-Right(r,56),8) *> & q.3 = <* Op-Left(Op-Right(r,64),8),Op-Left(Op-Right(r,72),8), Op-Left(Op-Right(r,80),8),Op-Left(Op-Right(r,88),8) *> & q.4 = <* Op-Left(Op-Right(r,96),8),Op-Left(Op-Right(r,104),8), Op-Left(Op-Right(r,112),8),Op-Left(Op-Right(r,120),8) *> & q.5 = <* Op-Left(Op-Right(r,128),8),Op-Left(Op-Right(r,136),8), Op-Left(Op-Right(r,144),8),Op-Left(Op-Right(r,152),8) *> & q.6 = <* Op-Left(Op-Right(r,160),8),Op-Left(Op-Right(r,168),8), Op-Left(Op-Right(r,176),8),Op-Left(Op-Right(r,184),8) *> & q.7 = <* Op-Left(Op-Right(r,192),8),Op-Left(Op-Right(r,200),8), Op-Left(Op-Right(r,208),8),Op-Left(Op-Right(r,216),8) *> & q.8 = <* Op-Left(Op-Right(r,224),8),Op-Left(Op-Right(r,232),8), Op-Left(Op-Right(r,240),8),Op-Right(r,248) *>; p in 8-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); then A8: ex v be Element of (4-tuples_on (8-tuples_on BOOLEAN))* st p = v & len v = 8; q in 8-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); then A9: ex v be Element of (4-tuples_on (8-tuples_on BOOLEAN))* st q = v & len v = 8; for i be Nat st 1 <= i & i <= len p holds p.i = q.i proof let i be Nat; assume 1 <= i & i <= len p; then i = 1 or ... or i = 8 by A8; hence thesis by A6,A7; end; hence p = q by A8,A9,FINSEQ_1:14; end; end; definition let SBT,MixColumns; let message be Element of 128-tuples_on BOOLEAN; let Key be Element of 128-tuples_on BOOLEAN; func AES128-ENC(SBT,MixColumns,message,Key) -> Element of 128-tuples_on BOOLEAN equals (AES-Statearray)".(AES-ENC(SBT,MixColumns,AES-Statearray.message, AES-KeyInitState128(Key))); correctness proof rng AES-Statearray = 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) by FUNCT_2:def 3; then (AES-Statearray)" is Function of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)),128-tuples_on BOOLEAN by FUNCT_2:25; hence thesis by FUNCT_2:5; end; end; definition let SBT,MixColumns; let cipher be Element of 128-tuples_on BOOLEAN; let Key be Element of 128-tuples_on BOOLEAN; func AES128-DEC(SBT,MixColumns,cipher,Key) -> Element of 128-tuples_on BOOLEAN equals (AES-Statearray)".(AES-DEC(SBT,MixColumns,AES-Statearray.cipher, AES-KeyInitState128(Key))); correctness proof rng AES-Statearray = 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) by FUNCT_2:def 3; then (AES-Statearray)" is Function of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), 128-tuples_on BOOLEAN by FUNCT_2:25; hence thesis by FUNCT_2:5; end; end; theorem for SBT be Permutation of (8-tuples_on BOOLEAN), MixColumns be Permutation of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), message,Key be Element of 128-tuples_on BOOLEAN holds AES128-DEC(SBT,MixColumns,AES128-ENC(SBT,MixColumns,message,Key),Key) = message proof let SBT be Permutation of (8-tuples_on BOOLEAN), MixColumns be Permutation of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), message,Key be Element of 128-tuples_on BOOLEAN; reconsider text = AES-Statearray.message as Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); reconsider sKey = AES-KeyInitState128(Key) as Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); reconsider cipher = AES-ENC(SBT,MixColumns,text,sKey) as Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); reconsider CBLOCK = AES128-ENC(SBT,MixColumns,message,Key) as Element of 128-tuples_on BOOLEAN; AES128-DEC(SBT,MixColumns,CBLOCK,Key) = (AES-Statearray)".(AES-DEC(SBT,MixColumns,cipher,sKey)) by LMINV1 .=(AES-Statearray)".text by LASTXX; hence thesis by FUNCT_2:26; end; definition let SBT,MixColumns; let message be Element of 128-tuples_on BOOLEAN; let Key be Element of 192-tuples_on BOOLEAN; func AES192-ENC(SBT,MixColumns,message,Key) -> Element of 128-tuples_on BOOLEAN equals (AES-Statearray)".(AES-ENC(SBT,MixColumns,AES-Statearray.message, AES-KeyInitState192(Key))); correctness proof rng AES-Statearray = 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) by FUNCT_2:def 3; then (AES-Statearray)" is Function of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)),128-tuples_on BOOLEAN by FUNCT_2:25; hence thesis by FUNCT_2:5; end; end; definition let SBT,MixColumns; let cipher be Element of 128-tuples_on BOOLEAN; let Key be Element of 192-tuples_on BOOLEAN; func AES192-DEC(SBT,MixColumns,cipher,Key) -> Element of 128-tuples_on BOOLEAN equals (AES-Statearray)".(AES-DEC(SBT,MixColumns,AES-Statearray.cipher, AES-KeyInitState192(Key))); correctness proof rng AES-Statearray = 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) by FUNCT_2:def 3; then (AES-Statearray)" is Function of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), 128-tuples_on BOOLEAN by FUNCT_2:25; hence thesis by FUNCT_2:5; end; end; theorem for SBT be Permutation of (8-tuples_on BOOLEAN), MixColumns be Permutation of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), message be Element of 128-tuples_on BOOLEAN, Key be Element of 192-tuples_on BOOLEAN holds AES192-DEC(SBT,MixColumns,AES192-ENC(SBT,MixColumns,message,Key),Key) = message proof let SBT be Permutation of (8-tuples_on BOOLEAN), MixColumns be Permutation of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), message be Element of 128-tuples_on BOOLEAN, Key be Element of 192-tuples_on BOOLEAN; reconsider text = AES-Statearray.message as Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); reconsider sKey = AES-KeyInitState192(Key) as Element of 6-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); reconsider cipher = AES-ENC(SBT,MixColumns,text,sKey) as Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); reconsider CBLOCK = AES192-ENC(SBT,MixColumns,message,Key) as Element of 128-tuples_on BOOLEAN; AES192-DEC(SBT,MixColumns,CBLOCK,Key) = (AES-Statearray)".(AES-DEC(SBT,MixColumns,cipher,sKey)) by LMINV1 .=(AES-Statearray)".text by LASTXX; hence thesis by FUNCT_2:26; end; definition let SBT,MixColumns; let message be Element of 128-tuples_on BOOLEAN; let Key be Element of 256-tuples_on BOOLEAN; func AES256-ENC(SBT,MixColumns,message,Key) -> Element of 128-tuples_on BOOLEAN equals (AES-Statearray)".(AES-ENC(SBT,MixColumns,AES-Statearray.message, AES-KeyInitState256(Key))); correctness proof rng AES-Statearray = 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) by FUNCT_2:def 3; then (AES-Statearray)" is Function of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)),128-tuples_on BOOLEAN by FUNCT_2:25; hence thesis by FUNCT_2:5; end; end; definition let SBT,MixColumns; let cipher be Element of 128-tuples_on BOOLEAN; let Key be Element of 256-tuples_on BOOLEAN; func AES256-DEC(SBT,MixColumns,cipher,Key) -> Element of 128-tuples_on BOOLEAN equals (AES-Statearray)".(AES-DEC(SBT,MixColumns,AES-Statearray.cipher, AES-KeyInitState256(Key))); correctness proof rng AES-Statearray = 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)) by FUNCT_2:def 3; then (AES-Statearray)" is Function of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), 128-tuples_on BOOLEAN by FUNCT_2:25; hence thesis by FUNCT_2:5; end; end; theorem for SBT be Permutation of (8-tuples_on BOOLEAN), MixColumns be Permutation of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), message be Element of 128-tuples_on BOOLEAN, Key be Element of 256-tuples_on BOOLEAN holds AES256-DEC(SBT,MixColumns,AES256-ENC(SBT,MixColumns,message,Key),Key) = message proof let SBT be Permutation of (8-tuples_on BOOLEAN), MixColumns be Permutation of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)), message be Element of 128-tuples_on BOOLEAN, Key be Element of 256-tuples_on BOOLEAN; reconsider text = AES-Statearray.message as Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); reconsider sKey = AES-KeyInitState256(Key) as Element of 8-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); reconsider cipher = AES-ENC(SBT,MixColumns,text,sKey) as Element of 4-tuples_on(4-tuples_on (8-tuples_on BOOLEAN)); reconsider CBLOCK = AES256-ENC(SBT,MixColumns,message,Key) as Element of 128-tuples_on BOOLEAN; AES256-DEC(SBT,MixColumns,CBLOCK,Key) = (AES-Statearray)".(AES-DEC(SBT,MixColumns,cipher,sKey)) by LMINV1 .=(AES-Statearray)".text by LASTXX; hence thesis by FUNCT_2:26; end;