Commit message: e_aes_cbc_hmac_sha1.c: align calculated MAC at cache line.
CVE: CVE-2013-0169
CWE: CWE-310
Vulnerability description: The TLS protocol 1.1 and 1.2 and the DTLS protocol 1.0 and 1.2, as used in OpenSSL, OpenJDK, PolarSSL, and other products, do not properly consider timing side-channel attacks on a MAC check requirement during the processing of malformed CBC padding, which allows remote attackers to conduct distinguishing attacks and plaintext-recovery attacks via statistical analysis of timing data for crafted packets, aka the "Lucky Thirteen" issue.

Project: openssl

static int aesni_cbc_hmac_sha1_ctrl(EVP_CIPHER_CTX *ctx, int type, int arg, void *ptr)
	{
	EVP_AES_HMAC_SHA1 *key = data(ctx);

	switch (type)
		{
	case EVP_CTRL_AEAD_SET_MAC_KEY:
		{
		unsigned int  i;
		unsigned char hmac_key[64];

		memset (hmac_key,0,sizeof(hmac_key));

		if (arg > (int)sizeof(hmac_key)) {
			SHA1_Init(&key->head);
			SHA1_Update(&key->head,ptr,arg);
			SHA1_Final(hmac_key,&key->head);
		} else {
			memcpy(hmac_key,ptr,arg);
		}

		for (i=0;i<sizeof(hmac_key);i++)
			hmac_key[i] ^= 0x36;		/* ipad */
		SHA1_Init(&key->head);
		SHA1_Update(&key->head,hmac_key,sizeof(hmac_key));

		for (i=0;i<sizeof(hmac_key);i++)
			hmac_key[i] ^= 0x36^0x5c;	/* opad */
		SHA1_Init(&key->tail);
		SHA1_Update(&key->tail,hmac_key,sizeof(hmac_key));

		OPENSSL_cleanse(hmac_key,sizeof(hmac_key));

		return 1;
		}
	case EVP_CTRL_AEAD_TLS1_AAD:
		{
		unsigned char *p=ptr;
		unsigned int   len=p[arg-2]<<8|p[arg-1];

		if (ctx->encrypt)
			{
			key->payload_length = len;
			if ((key->aux.tls_ver=p[arg-4]<<8|p[arg-3]) >= TLS1_1_VERSION) {
				len -= AES_BLOCK_SIZE;
				p[arg-2] = len>>8;
				p[arg-1] = len;
			}
			key->md = key->head;
			SHA1_Update(&key->md,p,arg);

			return (int)(((len+SHA_DIGEST_LENGTH+AES_BLOCK_SIZE)&-AES_BLOCK_SIZE)
				- len);
			}
		else
			{
			if (arg>13) arg = 13;
			memcpy(key->aux.tls_aad,ptr,arg);
			key->payload_length = arg;

			return SHA_DIGEST_LENGTH;
			}
		}
	default:
		return -1;
		}
	}

Project: openssl

static int aesni_cbc_hmac_sha1_init_key(EVP_CIPHER_CTX *ctx,
			const unsigned char *inkey,
			const unsigned char *iv, int enc)
	{
	EVP_AES_HMAC_SHA1 *key = data(ctx);
	int ret;

	if (enc)
		ret=aesni_set_encrypt_key(inkey,ctx->key_len*8,&key->ks);
	else
		ret=aesni_set_decrypt_key(inkey,ctx->key_len*8,&key->ks);

	SHA1_Init(&key->head);	/* handy when benchmarking */
	key->tail = key->head;
	key->md   = key->head;

	key->payload_length = NO_PAYLOAD_LENGTH;

	return ret<0?0:1;
	}

Project: openssl

const EVP_CIPHER *EVP_aes_128_cbc_hmac_sha1(void)
	{
	return NULL;
	}

Project: openssl

static void sha1_update(SHA_CTX *c,const void *data,size_t len)
{	const unsigned char *ptr = data;
	size_t res;

	if ((res = c->num)) {
		res = SHA_CBLOCK-res;
		if (len<res) res=len;
		SHA1_Update (c,ptr,res);
		ptr += res;
		len -= res;
	}

	res = len % SHA_CBLOCK;
	len -= res;

	if (len) {
		sha1_block_data_order(c,ptr,len/SHA_CBLOCK);

		ptr += len;
		c->Nh += len>>29;
		c->Nl += len<<=3;
		if (c->Nl<(unsigned int)len) c->Nh++;
	}

	if (res)
		SHA1_Update(c,ptr,res);
}

Project: openssl

const EVP_CIPHER *EVP_aes_256_cbc_hmac_sha1(void)
	{
	return(OPENSSL_ia32cap_P[1]&AESNI_CAPABLE?
		&aesni_256_cbc_hmac_sha1_cipher:NULL);
	}

Project: openssl

const EVP_CIPHER *EVP_aes_256_cbc_hmac_sha1(void)
	{
	return NULL;
	}

Project: openssl

const EVP_CIPHER *EVP_aes_128_cbc_hmac_sha1(void)
	{
	return(OPENSSL_ia32cap_P[1]&AESNI_CAPABLE?
		&aesni_128_cbc_hmac_sha1_cipher:NULL);
	}

Project: openssl

static int aesni_cbc_hmac_sha1_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out,
		      const unsigned char *in, size_t len)
	{
	EVP_AES_HMAC_SHA1 *key = data(ctx);
	unsigned int l;
	size_t	plen = key->payload_length,
		iv = 0,		/* explicit IV in TLS 1.1 and later */
		sha_off = 0;
#if defined(STITCHED_CALL)
	size_t	aes_off = 0,
		blocks;

	sha_off = SHA_CBLOCK-key->md.num;
#endif

	key->payload_length = NO_PAYLOAD_LENGTH;

	if (len%AES_BLOCK_SIZE) return 0;

	if (ctx->encrypt) {
		if (plen==NO_PAYLOAD_LENGTH)
			plen = len;
		else if (len!=((plen+SHA_DIGEST_LENGTH+AES_BLOCK_SIZE)&-AES_BLOCK_SIZE))
			return 0;
		else if (key->aux.tls_ver >= TLS1_1_VERSION)
			iv = AES_BLOCK_SIZE;

#if defined(STITCHED_CALL)
		if (plen>(sha_off+iv) && (blocks=(plen-(sha_off+iv))/SHA_CBLOCK)) {
			SHA1_Update(&key->md,in+iv,sha_off);

			aesni_cbc_sha1_enc(in,out,blocks,&key->ks,
				ctx->iv,&key->md,in+iv+sha_off);
			blocks *= SHA_CBLOCK;
			aes_off += blocks;
			sha_off += blocks;
			key->md.Nh += blocks>>29;
			key->md.Nl += blocks<<=3;
			if (key->md.Nl<(unsigned int)blocks) key->md.Nh++;
		} else {
			sha_off = 0;
		}
#endif
		sha_off += iv;
		SHA1_Update(&key->md,in+sha_off,plen-sha_off);

		if (plen!=len)	{	/* "TLS" mode of operation */
			if (in!=out)
				memcpy(out+aes_off,in+aes_off,plen-aes_off);

			/* calculate HMAC and append it to payload */
			SHA1_Final(out+plen,&key->md);
			key->md = key->tail;
			SHA1_Update(&key->md,out+plen,SHA_DIGEST_LENGTH);
			SHA1_Final(out+plen,&key->md);

			/* pad the payload|hmac */
			plen += SHA_DIGEST_LENGTH;
			for (l=len-plen-1;plen<len;plen++) out[plen]=l;
			/* encrypt HMAC|padding at once */
			aesni_cbc_encrypt(out+aes_off,out+aes_off,len-aes_off,
					&key->ks,ctx->iv,1);
		} else {
			aesni_cbc_encrypt(in+aes_off,out+aes_off,len-aes_off,
					&key->ks,ctx->iv,1);
		}
	} else {
		union { unsigned int  u[SHA_DIGEST_LENGTH/sizeof(unsigned int)];
			unsigned char c[32+SHA_DIGEST_LENGTH]; } mac, *pmac;

		/* arrange cache line alignment */
		pmac = (void *)(((size_t)mac.c+32)&((size_t)0-32));

		/* decrypt HMAC|padding at once */
		aesni_cbc_encrypt(in,out,len,
				&key->ks,ctx->iv,0);

		if (plen) {	/* "TLS" mode of operation */
			size_t inp_len, mask, j, i;
			unsigned int res, maxpad, pad, bitlen;
			int ret = 1;
			union {	unsigned int  u[SHA_LBLOCK];
				unsigned char c[SHA_CBLOCK]; }
				*data = (void *)key->md.data;

			if ((key->aux.tls_aad[plen-4]<<8|key->aux.tls_aad[plen-3])
			    >= TLS1_1_VERSION)
				iv = AES_BLOCK_SIZE;

			if (len<(iv+SHA_DIGEST_LENGTH+1))
				return 0;

			/* omit explicit iv */
			out += iv;
			len -= iv;

			/* figure out payload length */
			pad = out[len-1];
			maxpad = len-(SHA_DIGEST_LENGTH+1);
			maxpad |= (255-maxpad)>>(sizeof(maxpad)*8-8);
			maxpad &= 255;

			inp_len = len - (SHA_DIGEST_LENGTH+pad+1);
			mask = (0-((inp_len-len)>>(sizeof(inp_len)*8-1)));
			inp_len &= mask;
			ret &= (int)mask;

			key->aux.tls_aad[plen-2] = inp_len>>8;
			key->aux.tls_aad[plen-1] = inp_len;

			/* calculate HMAC */
			key->md = key->head;
			SHA1_Update(&key->md,key->aux.tls_aad,plen);

#if 1
			len -= SHA_DIGEST_LENGTH;		/* amend mac */
			if (len>=(256+SHA_CBLOCK)) {
				j = (len-(256+SHA_CBLOCK))&(0-SHA_CBLOCK);
				j += SHA_CBLOCK-key->md.num;
				SHA1_Update(&key->md,out,j);
				out += j;
				len -= j;
				inp_len -= j;
			}

			/* but pretend as if we hashed padded payload */
			bitlen = key->md.Nl+(inp_len<<3);	/* at most 18 bits */
#ifdef BSWAP
			bitlen = BSWAP(bitlen);
#else
			mac.c[0] = 0;
			mac.c[1] = (unsigned char)(bitlen>>16);
			mac.c[2] = (unsigned char)(bitlen>>8);
			mac.c[3] = (unsigned char)bitlen;
			bitlen = mac.u[0];
#endif

			pmac->u[0]=0;
			pmac->u[1]=0;
			pmac->u[2]=0;
			pmac->u[3]=0;
			pmac->u[4]=0;

			for (res=key->md.num, j=0;j<len;j++) {
				size_t c = out[j];
				mask = (j-inp_len)>>(sizeof(j)*8-8);
				c &= mask;
				c |= 0x80&~mask&~((inp_len-j)>>(sizeof(j)*8-8));
				data->c[res++]=(unsigned char)c;

				if (res!=SHA_CBLOCK) continue;

				mask = 0-((inp_len+8-j)>>(sizeof(j)*8-1));
				data->u[SHA_LBLOCK-1] |= bitlen&mask;
				sha1_block_data_order(&key->md,data,1);
				mask &= 0-((j-inp_len-73)>>(sizeof(j)*8-1));
				pmac->u[0] |= key->md.h0 & mask;
				pmac->u[1] |= key->md.h1 & mask;
				pmac->u[2] |= key->md.h2 & mask;
				pmac->u[3] |= key->md.h3 & mask;
				pmac->u[4] |= key->md.h4 & mask;
				res=0;
			}

			for(i=res;i<SHA_CBLOCK;i++,j++) data->c[i]=0;

			if (res>SHA_CBLOCK-8) {
				mask = 0-((inp_len+8-j)>>(sizeof(j)*8-1));
				data->u[SHA_LBLOCK-1] |= bitlen&mask;
				sha1_block_data_order(&key->md,data,1);
				mask &= 0-((j-inp_len-73)>>(sizeof(j)*8-1));
				pmac->u[0] |= key->md.h0 & mask;
				pmac->u[1] |= key->md.h1 & mask;
				pmac->u[2] |= key->md.h2 & mask;
				pmac->u[3] |= key->md.h3 & mask;
				pmac->u[4] |= key->md.h4 & mask;

				memset(data,0,SHA_CBLOCK);
				j+=64;
			}
			data->u[SHA_LBLOCK-1] = bitlen;
			sha1_block_data_order(&key->md,data,1);
			mask = 0-((j-inp_len-73)>>(sizeof(j)*8-1));
			pmac->u[0] |= key->md.h0 & mask;
			pmac->u[1] |= key->md.h1 & mask;
			pmac->u[2] |= key->md.h2 & mask;
			pmac->u[3] |= key->md.h3 & mask;
			pmac->u[4] |= key->md.h4 & mask;

#ifdef BSWAP
			pmac->u[0] = BSWAP(pmac->u[0]);
			pmac->u[1] = BSWAP(pmac->u[1]);
			pmac->u[2] = BSWAP(pmac->u[2]);
			pmac->u[3] = BSWAP(pmac->u[3]);
			pmac->u[4] = BSWAP(pmac->u[4]);
#else
			for (i=0;i<5;i++) {
				res = pmac->u[i];
				pmac->c[4*i+0]=(unsigned char)(res>>24);
				pmac->c[4*i+1]=(unsigned char)(res>>16);
				pmac->c[4*i+2]=(unsigned char)(res>>8);
				pmac->c[4*i+3]=(unsigned char)res;
			}
#endif
			len += SHA_DIGEST_LENGTH;
#else
			SHA1_Update(&key->md,out,inp_len);
			res = key->md.num;
			SHA1_Final(pmac->c,&key->md);

			{
			unsigned int inp_blocks, pad_blocks;

			/* but pretend as if we hashed padded payload */
			inp_blocks = 1+((SHA_CBLOCK-9-res)>>(sizeof(res)*8-1));
			res += (unsigned int)(len-inp_len);
			pad_blocks = res / SHA_CBLOCK;
			res %= SHA_CBLOCK;
			pad_blocks += 1+((SHA_CBLOCK-9-res)>>(sizeof(res)*8-1));
			for (;inp_blocks<pad_blocks;inp_blocks++)
				sha1_block_data_order(&key->md,data,1);
			}
#endif
			key->md = key->tail;
			SHA1_Update(&key->md,pmac->c,SHA_DIGEST_LENGTH);
			SHA1_Final(pmac->c,&key->md);

			/* verify HMAC */
			out += inp_len;
			len -= inp_len;
#if 1
			{
			unsigned char *p = out+len-1-maxpad-SHA_DIGEST_LENGTH;
			size_t off = out-p;
			unsigned int c, cmask;

			maxpad += SHA_DIGEST_LENGTH;
			for (res=0,i=0,j=0;j<maxpad;j++) {
				c = p[j];
				cmask = ((int)(j-off-SHA_DIGEST_LENGTH))>>(sizeof(int)*8-1);
				res |= (c^pad)&~cmask;	/* ... and padding */
				cmask &= ((int)(off-1-j))>>(sizeof(int)*8-1);
				res |= (c^pmac->c[i])&cmask;
				i += 1&cmask;
			}
			maxpad -= SHA_DIGEST_LENGTH;

			res = 0-((0-res)>>(sizeof(res)*8-1));
			ret &= (int)~res;
			}
#else
			for (res=0,i=0;i<SHA_DIGEST_LENGTH;i++)
				res |= out[i]^pmac->c[i];
			res = 0-((0-res)>>(sizeof(res)*8-1));
			ret &= (int)~res;

			/* verify padding */
			pad = (pad&~res) | (maxpad&res);
			out = out+len-1-pad;
			for (res=0,i=0;i<pad;i++)
				res |= out[i]^pad;

			res = (0-res)>>(sizeof(res)*8-1);
			ret &= (int)~res;
#endif
			return ret;
		} else {
			SHA1_Update(&key->md,out,len);
		}
	}

	return 1;
	}