Change .global to .globl in assembly files

* cipher/blowfish-arm.S: Change '.global' to '.globl'.
* cipher/camellia-aesni-avx-amd64.S: Ditto.
* cipher/camellia-aesni-avx2-amd64.S: Ditto.
* cipher/camellia-arm.S: Ditto.
* cipher/cast5-amd64.S: Ditto.
* cipher/rijndael-amd64.S: Ditto.
* cipher/rijndael-arm.S: Ditto.
* cipher/serpent-avx2-amd64.S: Ditto.
* cipher/serpent-sse2-amd64.S: Ditto.
* cipher/twofish-amd64.S: Ditto.
* cipher/twofish-arm.S: Ditto.
--

The .global keyword is used only in newer versions of GAS, so change these to
older .globl for better portability.

Signed-off-by: Jussi Kivilinna <jussi.kivilinna@iki.fi>
Add new benchmarking utility, bench-slope

* tests/Makefile.am (TESTS): Add 'bench-slope'.
* tests/bench-slope.c: New.
--

Bench-slope is new benchmarking tool for libgcrypt for obtaining overheadless
cycles/byte speed of cipher and hash algorithms. Tool measures the time each
operation (hash/encrypt/decrypt/authentication) takes for different buffer
sizes of from ~0kB to ~4kB and calculates the slope for these data points.
The default output is then given as nanosecs/byte and mebibytes/sec. If user
provides the speed of used CPU, tool also outputs cycles/byte result (CPU-Ghz *
ns/B = c/B).

Output without CPU speed (with ARM Cortex-A8):

$ tests/bench-slope hash

Hash:
                |  nanosecs/byte   mebibytes/sec   cycles/byte
 MD5            |      7.35 ns/B     129.7 MiB/s         - c/B
 SHA1           |     12.30 ns/B     77.53 MiB/s         - c/B
 RIPEMD160      |     15.96 ns/B     59.77 MiB/s         - c/B
 TIGER192       |     55.55 ns/B     17.17 MiB/s         - c/B
 SHA256         |     24.38 ns/B     39.12 MiB/s         - c/B
 SHA384         |     34.24 ns/B     27.86 MiB/s         - c/B
 SHA512         |     34.19 ns/B     27.90 MiB/s         - c/B
 SHA224         |     24.38 ns/B     39.12 MiB/s         - c/B
 MD4            |      5.68 ns/B     168.0 MiB/s         - c/B
 CRC32          |      9.26 ns/B     103.0 MiB/s         - c/B
 CRC32RFC1510   |      9.20 ns/B     103.6 MiB/s         - c/B
 CRC24RFC2440   |     87.31 ns/B     10.92 MiB/s         - c/B
 WHIRLPOOL      |     253.3 ns/B      3.77 MiB/s         - c/B
 TIGER          |     55.55 ns/B     17.17 MiB/s         - c/B
 TIGER2         |     55.55 ns/B     17.17 MiB/s         - c/B
 GOSTR3411_94   |     212.0 ns/B      4.50 MiB/s         - c/B
 STRIBOG256     |     630.1 ns/B      1.51 MiB/s         - c/B
 STRIBOG512     |     630.1 ns/B      1.51 MiB/s         - c/B
                =

With CPU speed (with Intel i5-4570, 3.2Ghz when turbo-boost disabled):

$ tests/bench-slope --cpu-mhz 3201 cipher arcfour blowfish aes
Cipher:
 ARCFOUR        |  nanosecs/byte   mebibytes/sec   cycles/byte
     STREAM enc |      2.43 ns/B     392.1 MiB/s      7.79 c/B
     STREAM dec |      2.44 ns/B     390.2 MiB/s      7.82 c/B
                =
 BLOWFISH       |  nanosecs/byte   mebibytes/sec   cycles/byte
        ECB enc |      7.62 ns/B     125.2 MiB/s     24.38 c/B
        ECB dec |      7.63 ns/B     125.0 MiB/s     24.43 c/B
        CBC enc |      9.18 ns/B     103.9 MiB/s     29.38 c/B
        CBC dec |      2.60 ns/B     366.2 MiB/s      8.34 c/B
        CFB enc |      9.17 ns/B     104.0 MiB/s     29.35 c/B
        CFB dec |      2.66 ns/B     358.1 MiB/s      8.53 c/B
        OFB enc |      8.97 ns/B     106.3 MiB/s     28.72 c/B
        OFB dec |      8.97 ns/B     106.3 MiB/s     28.71 c/B
        CTR enc |      2.60 ns/B     366.5 MiB/s      8.33 c/B
        CTR dec |      2.60 ns/B     367.1 MiB/s      8.32 c/B
                =
 AES            |  nanosecs/byte   mebibytes/sec   cycles/byte
        ECB enc |     0.439 ns/B    2173.0 MiB/s      1.40 c/B
        ECB dec |     0.489 ns/B    1949.5 MiB/s      1.57 c/B
        CBC enc |      1.64 ns/B     580.8 MiB/s      5.26 c/B
        CBC dec |     0.219 ns/B    4357.6 MiB/s     0.701 c/B
        CFB enc |      1.53 ns/B     623.6 MiB/s      4.90 c/B
        CFB dec |     0.219 ns/B    4350.5 MiB/s     0.702 c/B
        OFB enc |      1.51 ns/B     629.9 MiB/s      4.85 c/B
        OFB dec |      1.51 ns/B     629.9 MiB/s      4.85 c/B
        CTR enc |     0.288 ns/B    3308.5 MiB/s     0.923 c/B
        CTR dec |     0.288 ns/B    3316.9 MiB/s     0.920 c/B
        CCM enc |      1.93 ns/B     493.8 MiB/s      6.18 c/B
        CCM dec |      1.93 ns/B     494.0 MiB/s      6.18 c/B
       CCM auth |      1.64 ns/B     580.1 MiB/s      5.26 c/B
                =

Note: It's highly recommented to disable turbo-boost and dynamic CPU frequency
features when making these kind of measurements to reduce variance.

Note: The results are maximum performance for each operation; the actual speed
in application depends on various matters, such as: used buffer sizes, cache
usage, etc.

Signed-off-by: Jussi Kivilinna <jussi.kivilinna@iki.fi>
Add AMD64 assembly implementation of Salsa20

* cipher/Makefile.am: Add 'salsa20-amd64.S'.
* cipher/salsa20-amd64.S: New.
* cipher/salsa20.c (USE_AMD64): New macro.
[USE_AMD64] (_gcry_salsa20_amd64_keysetup, _gcry_salsa20_amd64_ivsetup)
(_gcry_salsa20_amd64_encrypt_blocks): New prototypes.
[USE_AMD64] (salsa20_keysetup, salsa20_ivsetup, salsa20_core): New.
[!USE_AMD64] (salsa20_core): Change 'src' to non-constant, update block
counter in 'salsa20_core' and return burn stack depth.
[!USE_AMD64] (salsa20_keysetup, salsa20_ivsetup): New.
(salsa20_do_setkey): Move generic key setup to 'salsa20_keysetup'.
(salsa20_setkey): Fix burn stack depth.
(salsa20_setiv): Move generic IV setup to 'salsa20_ivsetup'.
(salsa20_do_encrypt_stream) [USE_AMD64]: Process large buffers in AMD64
implementation.
(salsa20_do_encrypt_stream): Move stack burning to this function...
(salsa20_encrypt_stream, salsa20r12_encrypt_stream): ...from these
functions.
* configure.ac [x86-64]: Add 'salsa20-amd64.lo'.
--

Patch adds fast AMD64 assembly implementation for Salsa20. This implementation
is based on public domain code by D. J. Bernstein and it is available at
http://cr.yp.to/snuffle.html (amd64-xmm6). Implementation gains extra speed
by processing four blocks in parallel with help SSE2 instructions.

Benchmark results on Intel Core i5-4570 (3.2 Ghz):

Before:
SALSA20        |  nanosecs/byte   mebibytes/sec   cycles/byte
     STREAM enc |      3.88 ns/B     246.0 MiB/s     12.41 c/B
     STREAM dec |      3.88 ns/B     246.0 MiB/s     12.41 c/B
                =
 SALSA20R12     |  nanosecs/byte   mebibytes/sec   cycles/byte
     STREAM enc |      2.46 ns/B     387.9 MiB/s      7.87 c/B
     STREAM dec |      2.46 ns/B     387.7 MiB/s      7.87 c/B

After:
 SALSA20        |  nanosecs/byte   mebibytes/sec   cycles/byte
     STREAM enc |     0.985 ns/B     967.8 MiB/s      3.15 c/B
     STREAM dec |     0.987 ns/B     966.5 MiB/s      3.16 c/B
                =
 SALSA20R12     |  nanosecs/byte   mebibytes/sec   cycles/byte
     STREAM enc |     0.636 ns/B    1500.5 MiB/s      2.03 c/B
     STREAM dec |     0.636 ns/B    1499.2 MiB/s      2.04 c/B

Signed-off-by: Jussi Kivilinna <jussi.kivilinna@iki.fi>
Add ARM NEON assembly implementation of Salsa20

* cipher/Makefile.am: Add 'salsa20-armv7-neon.S'.
* cipher/salsa20-armv7-neon.S: New.
* cipher/salsa20.c [USE_ARM_NEON_ASM]: New macro.
(struct SALSA20_context_s, salsa20_core_t, salsa20_keysetup_t)
(salsa20_ivsetup_t): New.
(SALSA20_context_t) [USE_ARM_NEON_ASM]: Add 'use_neon'.
(SALSA20_context_t): Add 'keysetup', 'ivsetup' and 'core'.
(salsa20_core): Change 'src' argument to 'ctx'.
[USE_ARM_NEON_ASM] (_gcry_arm_neon_salsa20_encrypt): New prototype.
[USE_ARM_NEON_ASM] (salsa20_core_neon, salsa20_keysetup_neon)
(salsa20_ivsetup_neon): New.
(salsa20_do_setkey): Setup keysetup, ivsetup and core with default
functions.
(salsa20_do_setkey) [USE_ARM_NEON_ASM]: When NEON support detect,
set keysetup, ivsetup and core with ARM NEON functions.
(salsa20_do_setkey): Call 'ctx->keysetup'.
(salsa20_setiv): Call 'ctx->ivsetup'.
(salsa20_do_encrypt_stream) [USE_ARM_NEON_ASM]: Process large buffers
in ARM NEON implementation.
(salsa20_do_encrypt_stream): Call 'ctx->core' instead of directly
calling 'salsa20_core'.
(selftest): Add test to check large buffer processing and block counter
updating.
* configure.ac [neonsupport]: 'Add salsa20-armv7-neon.lo'.
--

Patch adds fast ARM NEON assembly implementation for Salsa20. Implementation
gains extra speed by processing three blocks in parallel with help of ARM
NEON vector processing unit.

This implementation is based on public domain code by Peter Schwabe and D. J.
Bernstein and it is available in SUPERCOP benchmarking framework. For more
details on this work, check paper "NEON crypto" by Daniel J. Bernstein and
Peter Schwabe:
    http://cryptojedi.org/papers/#neoncrypto

Benchmark results on Cortex-A8 (1008 Mhz):

Before:
 SALSA20        |  nanosecs/byte   mebibytes/sec   cycles/byte
     STREAM enc |     18.88 ns/B     50.51 MiB/s     19.03 c/B
     STREAM dec |     18.89 ns/B     50.49 MiB/s     19.04 c/B
                =
 SALSA20R12     |  nanosecs/byte   mebibytes/sec   cycles/byte
     STREAM enc |     13.60 ns/B     70.14 MiB/s     13.71 c/B
     STREAM dec |     13.60 ns/B     70.13 MiB/s     13.71 c/B

After:
 SALSA20        |  nanosecs/byte   mebibytes/sec   cycles/byte
     STREAM enc |      5.48 ns/B     174.1 MiB/s      5.52 c/B
     STREAM dec |      5.47 ns/B     174.2 MiB/s      5.52 c/B
                =
 SALSA20R12     |  nanosecs/byte   mebibytes/sec   cycles/byte
     STREAM enc |      3.65 ns/B     260.9 MiB/s      3.68 c/B
     STREAM dec |      3.65 ns/B     261.6 MiB/s      3.67 c/B

Signed-off-by: Jussi Kivilinna <jussi.kivilinna@iki.fi>
Add ARM NEON assembly implementation of Serpent

* cipher/Makefile.am: Add 'serpent-armv7-neon.S'.
* cipher/serpent-armv7-neon.S: New.
* cipher/serpent.c (USE_NEON): New macro.
(serpent_context_t) [USE_NEON]: Add 'use_neon'.
[USE_NEON] (_gcry_serpent_neon_ctr_enc, _gcry_serpent_neon_cfb_dec)
(_gcry_serpent_neon_cbc_dec): New prototypes.
(serpent_setkey_internal) [USE_NEON]: Detect NEON support.
(_gcry_serpent_neon_ctr_enc, _gcry_serpent_neon_cfb_dec)
(_gcry_serpent_neon_cbc_dec) [USE_NEON]: Use NEON implementations
to process eight blocks in parallel.
* configure.ac [neonsupport]: Add 'serpent-armv7-neon.lo'.
--

Patch adds ARM NEON optimized implementation of Serpent cipher
to speed up parallelizable bulk operations.

Benchmarks on ARM Cortex-A8 (armhf, 1008 Mhz):

Old:
 SERPENT128     |  nanosecs/byte   mebibytes/sec   cycles/byte
        CBC dec |     43.53 ns/B     21.91 MiB/s     43.88 c/B
        CFB dec |     44.77 ns/B     21.30 MiB/s     45.13 c/B
        CTR enc |     45.21 ns/B     21.10 MiB/s     45.57 c/B
        CTR dec |     45.21 ns/B     21.09 MiB/s     45.57 c/B
New:
 SERPENT128     |  nanosecs/byte   mebibytes/sec   cycles/byte
        CBC dec |     26.26 ns/B     36.32 MiB/s     26.47 c/B
        CFB dec |     26.21 ns/B     36.38 MiB/s     26.42 c/B
        CTR enc |     26.20 ns/B     36.40 MiB/s     26.41 c/B
        CTR dec |     26.20 ns/B     36.40 MiB/s     26.41 c/B

Signed-off-by: Jussi Kivilinna <jussi.kivilinna@iki.fi>
Fix typos in documentation

* doc/gcrypt.texi: Fix some typos.
--

Signed-off-by: Jussi Kivilinna <jussi.kivilinna@iki.fi>