| /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) |
| * All rights reserved. |
| * |
| * This package is an SSL implementation written |
| * by Eric Young (eay@cryptsoft.com). |
| * The implementation was written so as to conform with Netscapes SSL. |
| * |
| * This library is free for commercial and non-commercial use as long as |
| * the following conditions are aheared to. The following conditions |
| * apply to all code found in this distribution, be it the RC4, RSA, |
| * lhash, DES, etc., code; not just the SSL code. The SSL documentation |
| * included with this distribution is covered by the same copyright terms |
| * except that the holder is Tim Hudson (tjh@cryptsoft.com). |
| * |
| * Copyright remains Eric Young's, and as such any Copyright notices in |
| * the code are not to be removed. |
| * If this package is used in a product, Eric Young should be given attribution |
| * as the author of the parts of the library used. |
| * This can be in the form of a textual message at program startup or |
| * in documentation (online or textual) provided with the package. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * 3. All advertising materials mentioning features or use of this software |
| * must display the following acknowledgement: |
| * "This product includes cryptographic software written by |
| * Eric Young (eay@cryptsoft.com)" |
| * The word 'cryptographic' can be left out if the rouines from the library |
| * being used are not cryptographic related :-). |
| * 4. If you include any Windows specific code (or a derivative thereof) from |
| * the apps directory (application code) you must include an acknowledgement: |
| * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" |
| * |
| * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND |
| * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE |
| * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| * SUCH DAMAGE. |
| * |
| * The licence and distribution terms for any publically available version or |
| * derivative of this code cannot be changed. i.e. this code cannot simply be |
| * copied and put under another distribution licence |
| * [including the GNU Public Licence.] */ |
| |
| #include <openssl/aead.h> |
| |
| #include <assert.h> |
| |
| #include <openssl/cipher.h> |
| #include <openssl/err.h> |
| #include <openssl/md5.h> |
| #include <openssl/mem.h> |
| #include <openssl/obj.h> |
| #include <openssl/rc4.h> |
| |
| #include "internal.h" |
| |
| |
| static int rc4_init_key(EVP_CIPHER_CTX *ctx, const uint8_t *key, |
| const uint8_t *iv, int enc) { |
| RC4_KEY *rc4key = (RC4_KEY *)ctx->cipher_data; |
| |
| RC4_set_key(rc4key, EVP_CIPHER_CTX_key_length(ctx), key); |
| return 1; |
| } |
| |
| static int rc4_cipher(EVP_CIPHER_CTX *ctx, uint8_t *out, const uint8_t *in, |
| size_t in_len) { |
| RC4_KEY *rc4key = (RC4_KEY *)ctx->cipher_data; |
| |
| RC4(rc4key, in_len, in, out); |
| return 1; |
| } |
| |
| static const EVP_CIPHER rc4 = { |
| NID_rc4, 1 /* block_size */, 16 /* key_size */, |
| 0 /* iv_len */, sizeof(RC4_KEY), EVP_CIPH_VARIABLE_LENGTH, |
| NULL /* app_data */, rc4_init_key, rc4_cipher, |
| NULL /* cleanup */, NULL /* ctrl */, }; |
| |
| const EVP_CIPHER *EVP_rc4(void) { return &rc4; } |
| |
| |
| struct aead_rc4_md5_tls_ctx { |
| RC4_KEY rc4; |
| MD5_CTX head, tail, md; |
| size_t payload_length; |
| unsigned char tag_len; |
| }; |
| |
| |
| static int |
| aead_rc4_md5_tls_init(EVP_AEAD_CTX *ctx, const uint8_t *key, size_t key_len, |
| size_t tag_len) { |
| struct aead_rc4_md5_tls_ctx *rc4_ctx; |
| size_t i; |
| uint8_t hmac_key[MD5_CBLOCK]; |
| |
| if (tag_len == EVP_AEAD_DEFAULT_TAG_LENGTH) { |
| tag_len = MD5_DIGEST_LENGTH; |
| } |
| |
| if (tag_len > MD5_DIGEST_LENGTH) { |
| OPENSSL_PUT_ERROR(CIPHER, aead_rc4_md5_tls_init, CIPHER_R_TOO_LARGE); |
| return 0; |
| } |
| |
| /* The keys consists of |MD5_DIGEST_LENGTH| bytes of HMAC(MD5) key followed |
| * by some number of bytes of RC4 key. */ |
| if (key_len <= MD5_DIGEST_LENGTH) { |
| OPENSSL_PUT_ERROR(CIPHER, aead_rc4_md5_tls_init, CIPHER_R_BAD_KEY_LENGTH); |
| return 0; |
| } |
| |
| rc4_ctx = OPENSSL_malloc(sizeof(struct aead_rc4_md5_tls_ctx)); |
| if (rc4_ctx == NULL) { |
| OPENSSL_PUT_ERROR(CIPHER, aead_rc4_md5_tls_init, ERR_R_MALLOC_FAILURE); |
| return 0; |
| } |
| memset(rc4_ctx, 0, sizeof(struct aead_rc4_md5_tls_ctx)); |
| |
| RC4_set_key(&rc4_ctx->rc4, key_len - MD5_DIGEST_LENGTH, |
| key + MD5_DIGEST_LENGTH); |
| |
| memset(hmac_key, 0, sizeof(hmac_key)); |
| memcpy(hmac_key, key, MD5_DIGEST_LENGTH); |
| for (i = 0; i < sizeof(hmac_key); i++) { |
| hmac_key[i] ^= 0x36; |
| } |
| MD5_Init(&rc4_ctx->head); |
| MD5_Update(&rc4_ctx->head, hmac_key, sizeof(hmac_key)); |
| for (i = 0; i < sizeof(hmac_key); i++) { |
| hmac_key[i] ^= 0x36 ^ 0x5c; |
| } |
| MD5_Init(&rc4_ctx->tail); |
| MD5_Update(&rc4_ctx->tail, hmac_key, sizeof(hmac_key)); |
| |
| rc4_ctx->tag_len = tag_len; |
| ctx->aead_state = rc4_ctx; |
| |
| return 1; |
| } |
| |
| static void aead_rc4_md5_tls_cleanup(EVP_AEAD_CTX *ctx) { |
| struct aead_rc4_md5_tls_ctx *rc4_ctx = ctx->aead_state; |
| OPENSSL_cleanse(rc4_ctx, sizeof(struct aead_rc4_md5_tls_ctx)); |
| OPENSSL_free(rc4_ctx); |
| } |
| |
| #if !defined(OPENSSL_NO_ASM) && defined(OPENSSL_X86_64) |
| #define STITCHED_CALL |
| |
| /* rc4_md5_enc is defined in rc4_md5-x86_64.pl */ |
| void rc4_md5_enc(RC4_KEY *key, const void *in0, void *out, MD5_CTX *ctx, |
| const void *inp, size_t blocks); |
| #endif |
| |
| static int aead_rc4_md5_tls_seal(const EVP_AEAD_CTX *ctx, uint8_t *out, |
| size_t *out_len, size_t max_out_len, |
| const uint8_t *nonce, size_t nonce_len, |
| const uint8_t *in, size_t in_len, |
| const uint8_t *ad, size_t ad_len) { |
| struct aead_rc4_md5_tls_ctx *rc4_ctx = ctx->aead_state; |
| MD5_CTX md; |
| #if defined(STITCHED_CALL) |
| size_t rc4_off, md5_off, blocks; |
| extern unsigned int OPENSSL_ia32cap_P[]; |
| #else |
| const size_t rc4_off = 0; |
| const size_t md5_off = 0; |
| #endif |
| uint8_t digest[MD5_DIGEST_LENGTH]; |
| |
| if (in_len + rc4_ctx->tag_len < in_len) { |
| OPENSSL_PUT_ERROR(CIPHER, aead_rc4_md5_tls_seal, CIPHER_R_TOO_LARGE); |
| return 0; |
| } |
| |
| if (nonce_len != 0) { |
| OPENSSL_PUT_ERROR(CIPHER, aead_rc4_md5_tls_seal, CIPHER_R_IV_TOO_LARGE); |
| return 0; |
| } |
| |
| if (max_out_len < in_len + rc4_ctx->tag_len) { |
| OPENSSL_PUT_ERROR(CIPHER, aead_rc4_md5_tls_seal, CIPHER_R_BUFFER_TOO_SMALL); |
| return 0; |
| } |
| |
| if (nonce_len != 0) { |
| OPENSSL_PUT_ERROR(CIPHER, aead_rc4_md5_tls_seal, CIPHER_R_TOO_LARGE); |
| return 0; |
| } |
| |
| memcpy(&md, &rc4_ctx->head, sizeof(MD5_CTX)); |
| /* The MAC's payload begins with the additional data. See |
| * https://tools.ietf.org/html/rfc5246#section-6.2.3.1 */ |
| MD5_Update(&md, ad, ad_len); |
| |
| #if defined(STITCHED_CALL) |
| /* 32 is $MOD from rc4_md5-x86_64.pl. */ |
| rc4_off = 32 - 1 - (rc4_ctx->rc4.x & (32 - 1)); |
| md5_off = MD5_CBLOCK - md.num; |
| /* Ensure RC4 is behind MD5. */ |
| if (rc4_off > md5_off) { |
| md5_off += MD5_CBLOCK; |
| } |
| assert(md5_off >= rc4_off); |
| |
| if (in_len > md5_off && (blocks = (in_len - md5_off) / MD5_CBLOCK) && |
| (OPENSSL_ia32cap_P[0] & (1 << 20)) == 0) { |
| /* Process the initial portions of the plaintext normally. */ |
| MD5_Update(&md, in, md5_off); |
| RC4(&rc4_ctx->rc4, rc4_off, in, out); |
| |
| /* Process the next |blocks| blocks of plaintext with stitched routines. */ |
| rc4_md5_enc(&rc4_ctx->rc4, in + rc4_off, out + rc4_off, &md, in + md5_off, |
| blocks); |
| blocks *= MD5_CBLOCK; |
| rc4_off += blocks; |
| md5_off += blocks; |
| md.Nh += blocks >> 29; |
| md.Nl += blocks <<= 3; |
| if (md.Nl < (unsigned int)blocks) { |
| md.Nh++; |
| } |
| } else { |
| rc4_off = 0; |
| md5_off = 0; |
| } |
| #endif |
| /* Finish computing the MAC. */ |
| MD5_Update(&md, in + md5_off, in_len - md5_off); |
| MD5_Final(digest, &md); |
| |
| memcpy(&md, &rc4_ctx->tail, sizeof(MD5_CTX)); |
| MD5_Update(&md, digest, sizeof(digest)); |
| if (rc4_ctx->tag_len == MD5_DIGEST_LENGTH) { |
| MD5_Final(out + in_len, &md); |
| } else { |
| MD5_Final(digest, &md); |
| memcpy(out + in_len, digest, rc4_ctx->tag_len); |
| } |
| |
| /* Encrypt the remainder of the plaintext and the MAC. */ |
| RC4(&rc4_ctx->rc4, in_len - rc4_off, in + rc4_off, out + rc4_off); |
| RC4(&rc4_ctx->rc4, MD5_DIGEST_LENGTH, out + in_len, out + in_len); |
| |
| *out_len = in_len + rc4_ctx->tag_len; |
| return 1; |
| } |
| |
| static int aead_rc4_md5_tls_open(const EVP_AEAD_CTX *ctx, uint8_t *out, |
| size_t *out_len, size_t max_out_len, |
| const uint8_t *nonce, size_t nonce_len, |
| const uint8_t *in, size_t in_len, |
| const uint8_t *ad, size_t ad_len) { |
| struct aead_rc4_md5_tls_ctx *rc4_ctx = ctx->aead_state; |
| MD5_CTX md; |
| size_t plaintext_len; |
| #if defined(STITCHED_CALL) |
| unsigned int l; |
| size_t rc4_off, md5_off, blocks; |
| extern unsigned int OPENSSL_ia32cap_P[]; |
| #else |
| const size_t rc4_off = 0; |
| const size_t md5_off = 0; |
| #endif |
| uint8_t digest[MD5_DIGEST_LENGTH]; |
| |
| if (in_len < rc4_ctx->tag_len) { |
| OPENSSL_PUT_ERROR(CIPHER, aead_rc4_md5_tls_open, CIPHER_R_BAD_DECRYPT); |
| return 0; |
| } |
| |
| plaintext_len = in_len - rc4_ctx->tag_len; |
| |
| if (nonce_len != 0) { |
| OPENSSL_PUT_ERROR(CIPHER, aead_rc4_md5_tls_seal, CIPHER_R_TOO_LARGE); |
| return 0; |
| } |
| |
| if (max_out_len < plaintext_len) { |
| OPENSSL_PUT_ERROR(CIPHER, aead_rc4_md5_tls_open, CIPHER_R_BUFFER_TOO_SMALL); |
| return 0; |
| } |
| |
| memcpy(&md, &rc4_ctx->head, sizeof(MD5_CTX)); |
| /* The MAC's payload begins with the additional data. See |
| * https://tools.ietf.org/html/rfc5246#section-6.2.3.1 */ |
| MD5_Update(&md, ad, ad_len); |
| |
| #if defined(STITCHED_CALL) |
| rc4_off = 32 - 1 - (rc4_ctx->rc4.x & (32 - 1)); |
| md5_off = MD5_CBLOCK - md.num; |
| /* Ensure MD5 is a full block behind RC4 so it has plaintext to operate on in |
| * both normal and stitched routines. */ |
| if (md5_off > rc4_off) { |
| rc4_off += 2 * MD5_CBLOCK; |
| } else { |
| rc4_off += MD5_CBLOCK; |
| } |
| |
| if (in_len > rc4_off && (blocks = (in_len - rc4_off) / MD5_CBLOCK) && |
| (OPENSSL_ia32cap_P[0] & (1 << 20)) == 0) { |
| /* Decrypt the initial portion of the ciphertext and digest the plaintext |
| * normally. */ |
| RC4(&rc4_ctx->rc4, rc4_off, in, out); |
| MD5_Update(&md, out, md5_off); |
| |
| /* Decrypt and digest the next |blocks| blocks of ciphertext with the |
| * stitched routines. */ |
| rc4_md5_enc(&rc4_ctx->rc4, in + rc4_off, out + rc4_off, &md, out + md5_off, |
| blocks); |
| blocks *= MD5_CBLOCK; |
| rc4_off += blocks; |
| md5_off += blocks; |
| l = (md.Nl + (blocks << 3)) & 0xffffffffU; |
| if (l < md.Nl) { |
| md.Nh++; |
| } |
| md.Nl = l; |
| md.Nh += blocks >> 29; |
| } else { |
| md5_off = 0; |
| rc4_off = 0; |
| } |
| #endif |
| |
| /* Process the remainder of the input. */ |
| RC4(&rc4_ctx->rc4, in_len - rc4_off, in + rc4_off, out + rc4_off); |
| MD5_Update(&md, out + md5_off, plaintext_len - md5_off); |
| MD5_Final(digest, &md); |
| |
| /* Calculate HMAC and verify it */ |
| memcpy(&md, &rc4_ctx->tail, sizeof(MD5_CTX)); |
| MD5_Update(&md, digest, MD5_DIGEST_LENGTH); |
| MD5_Final(digest, &md); |
| |
| if (CRYPTO_memcmp(out + plaintext_len, digest, rc4_ctx->tag_len)) { |
| OPENSSL_PUT_ERROR(CIPHER, aead_rc4_md5_tls_open, CIPHER_R_BAD_DECRYPT); |
| return 0; |
| } |
| |
| *out_len = plaintext_len; |
| return 1; |
| } |
| |
| static const EVP_AEAD aead_rc4_md5_tls = { |
| 16 + MD5_DIGEST_LENGTH, /* key len (RC4 + MD5) */ |
| 0, /* nonce len */ |
| MD5_DIGEST_LENGTH, /* overhead */ |
| MD5_DIGEST_LENGTH, /* max tag length */ |
| aead_rc4_md5_tls_init, aead_rc4_md5_tls_cleanup, |
| aead_rc4_md5_tls_seal, aead_rc4_md5_tls_open, |
| }; |
| |
| const EVP_AEAD *EVP_aead_rc4_md5_tls() { return &aead_rc4_md5_tls; } |