/*
* Copyright 2011-2021 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the Apache License 2.0 (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*/
/*
* MD5 and RC4 low level APIs are deprecated for public use, but still ok for
* internal use.
*/
#include "internal/deprecated.h"
#include "internal/cryptlib.h"
#include <openssl/opensslconf.h>
#include <stdio.h>
#include <string.h>
#if !defined(OPENSSL_NO_RC4) && !defined(OPENSSL_NO_MD5)
# include <openssl/crypto.h>
# include <openssl/evp.h>
# include <openssl/objects.h>
# include <openssl/rc4.h>
# include <openssl/md5.h>
# include "crypto/evp.h"
typedef struct {
RC4_KEY ks;
MD5_CTX head, tail, md;
size_t payload_length;
} EVP_RC4_HMAC_MD5;
# define NO_PAYLOAD_LENGTH ((size_t)-1)
void rc4_md5_enc(RC4_KEY *key, const void *in0, void *out,
MD5_CTX *ctx, const void *inp, size_t blocks);
# define data(ctx) ((EVP_RC4_HMAC_MD5 *)EVP_CIPHER_CTX_get_cipher_data(ctx))
static int rc4_hmac_md5_init_key(EVP_CIPHER_CTX *ctx,
const unsigned char *inkey,
const unsigned char *iv, int enc)
{
EVP_RC4_HMAC_MD5 *key = data(ctx);
const int keylen = EVP_CIPHER_CTX_get_key_length(ctx);
if (keylen <= 0)
return 0;
RC4_set_key(&key->ks, keylen, inkey);
MD5_Init(&key->head); /* handy when benchmarking */
key->tail = key->head;
key->md = key->head;
key->payload_length = NO_PAYLOAD_LENGTH;
return 1;
}
# if defined(RC4_ASM) && defined(MD5_ASM) && ( \
defined(__x86_64) || defined(__x86_64__) || \
defined(_M_AMD64) || defined(_M_X64) )
# define STITCHED_CALL
# endif
# if !defined(STITCHED_CALL)
# define rc4_off 0
# define md5_off 0
# endif
static int rc4_hmac_md5_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out,
const unsigned char *in, size_t len)
{
EVP_RC4_HMAC_MD5 *key = data(ctx);
# if defined(STITCHED_CALL)
size_t rc4_off = 32 - 1 - (key->ks.x & (32 - 1)), /* 32 is $MOD from
* rc4_md5-x86_64.pl */
md5_off = MD5_CBLOCK - key->md.num, blocks;
unsigned int l;
# endif
size_t plen = key->payload_length;
if (plen != NO_PAYLOAD_LENGTH && len != (plen + MD5_DIGEST_LENGTH))
return 0;
if (EVP_CIPHER_CTX_is_encrypting(ctx)) {
if (plen == NO_PAYLOAD_LENGTH)
plen = len;
# if defined(STITCHED_CALL)
/* cipher has to "fall behind" */
if (rc4_off > md5_off)
md5_off += MD5_CBLOCK;
if (plen > md5_off && (blocks = (plen - md5_off) / MD5_CBLOCK) &&
(OPENSSL_ia32cap_P[0] & (1 << 20)) == 0) {
MD5_Update(&key->md, in, md5_off);
RC4(&key->ks, rc4_off, in, out);
rc4_md5_enc(&key->ks, in + rc4_off, out + rc4_off,
&key->md, in + md5_off, blocks);
blocks *= MD5_CBLOCK;
rc4_off += blocks;
md5_off += blocks;
key->md.Nh += blocks >> 29;
key->md.Nl += blocks <<= 3;
if (key->md.Nl < (unsigned int)blocks)
key->md.Nh++;
} else {
rc4_off = 0;
md5_off = 0;
}
# endif
MD5_Update(&key->md, in + md5_off, plen - md5_off);
if (plen != len) { /* "TLS" mode of operation */
if (in != out)
memcpy(out + rc4_off, in + rc4_off, plen - rc4_off);
/* calculate HMAC and append it to payload */
MD5_Final(out + plen, &key->md);
key->md = key->tail;
MD5_Update(&key->md, out + plen, MD5_DIGEST_LENGTH);
MD5_Final(out + plen, &key->md);
/* encrypt HMAC at once */
RC4(&key->ks, len - rc4_off, out + rc4_off, out + rc4_off);
} else {
RC4(&key->ks, len - rc4_off, in + rc4_off, out + rc4_off);
}
} else {
unsigned char mac[MD5_DIGEST_LENGTH];
# if defined(STITCHED_CALL)
/* digest has to "fall behind" */
if (md5_off > rc4_off)
rc4_off += 2 * MD5_CBLOCK;
else
rc4_off += MD5_CBLOCK;
if (len > rc4_off && (blocks = (len - rc4_off) / MD5_CBLOCK) &&
(OPENSSL_ia32cap_P[0] & (1 << 20)) == 0) {
RC4(&key->ks, rc4_off, in, out);
MD5_Update(&key->md, out, md5_off);
rc4_md5_enc(&key->ks, in + rc4_off, out + rc4_off,
&key->md, out + md5_off, blocks);
blocks *= MD5_CBLOCK;
rc4_off += blocks;
md5_off += blocks;
l = (key->md.Nl + (blocks << 3)) & 0xffffffffU;
if (l < key->md.Nl)
key->md.Nh++;
key->md.Nl = l;
key->md.Nh += blocks >> 29;
} else {
md5_off = 0;
rc4_off = 0;
}
# endif
/* decrypt HMAC at once */
RC4(&key->ks, len - rc4_off, in + rc4_off, out + rc4_off);
if (plen != NO_PAYLOAD_LENGTH) { /* "TLS" mode of operation */
MD5_Update(&key->md, out + md5_off, plen - md5_off);
/* calculate HMAC and verify it */
MD5_Final(mac, &key->md);
key->md = key->tail;
MD5_Update(&key->md, mac, MD5_DIGEST_LENGTH);
MD5_Final(mac, &key->md);
if (CRYPTO_memcmp(out + plen, mac, MD5_DIGEST_LENGTH))
return 0;
} else {
MD5_Update(&key->md, out + md5_off, len - md5_off);
}
}
key->payload_length = NO_PAYLOAD_LENGTH;
return 1;
}
static int rc4_hmac_md5_ctrl(EVP_CIPHER_CTX *ctx, int type, int arg,
void *ptr)
{
EVP_RC4_HMAC_MD5 *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)) {
MD5_Init(&key->head);
MD5_Update(&key->head, ptr, arg);
MD5_Final(hmac_key, &key->head);
} else {
memcpy(hmac_key, ptr, arg);
}
for (i = 0; i < sizeof(hmac_key); i++)
hmac_key[i] ^= 0x36; /* ipad */
MD5_Init(&key->head);
MD5_Update(&key->head, hmac_key, sizeof(hmac_key));
for (i = 0; i < sizeof(hmac_key); i++)
hmac_key[i] ^= 0x36 ^ 0x5c; /* opad */
MD5_Init(&key->tail);
MD5_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;
if (arg != EVP_AEAD_TLS1_AAD_LEN)
return -1;
len = p[arg - 2] << 8 | p[arg - 1];
if (!EVP_CIPHER_CTX_is_encrypting(ctx)) {
if (len < MD5_DIGEST_LENGTH)
return -1;
len -= MD5_DIGEST_LENGTH;
p[arg - 2] = len >> 8;
p[arg - 1] = len;
}
key->payload_length = len;
key->md = key->head;
MD5_Update(&key->md, p, arg);
return MD5_DIGEST_LENGTH;
}
default:
return -1;
}
}
static EVP_CIPHER r4_hmac_md5_cipher = {
# ifdef NID_rc4_hmac_md5
NID_rc4_hmac_md5,
# else
NID_undef,
# endif
1, EVP_RC4_KEY_SIZE, 0,
EVP_CIPH_STREAM_CIPHER | EVP_CIPH_VARIABLE_LENGTH |
EVP_CIPH_FLAG_AEAD_CIPHER,
EVP_ORIG_GLOBAL,
rc4_hmac_md5_init_key,
rc4_hmac_md5_cipher,
NULL,
sizeof(EVP_RC4_HMAC_MD5),
NULL,
NULL,
rc4_hmac_md5_ctrl,
NULL
};
const EVP_CIPHER *EVP_rc4_hmac_md5(void)
{
return &r4_hmac_md5_cipher;
}
#endif