diff options
Diffstat (limited to 'third_party/boringssl/src/crypto/cipher/e_rc4.c')
| -rw-r--r-- | third_party/boringssl/src/crypto/cipher/e_rc4.c | 397 |
1 files changed, 397 insertions, 0 deletions
diff --git a/third_party/boringssl/src/crypto/cipher/e_rc4.c b/third_party/boringssl/src/crypto/cipher/e_rc4.c new file mode 100644 index 0000000000..e05b9fda53 --- /dev/null +++ b/third_party/boringssl/src/crypto/cipher/e_rc4.c @@ -0,0 +1,397 @@ +/* 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 <string.h> + +#include <openssl/cipher.h> +#include <openssl/cpu.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, 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, 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, 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; +#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, CIPHER_R_TOO_LARGE); + return 0; + } + + if (nonce_len != 0) { + OPENSSL_PUT_ERROR(CIPHER, CIPHER_R_IV_TOO_LARGE); + return 0; + } + + if (max_out_len < in_len + rc4_ctx->tag_len) { + OPENSSL_PUT_ERROR(CIPHER, CIPHER_R_BUFFER_TOO_SMALL); + return 0; + } + + if (nonce_len != 0) { + OPENSSL_PUT_ERROR(CIPHER, 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); + + /* To allow for CBC mode which changes cipher length, |ad| doesn't include the + * length for legacy ciphers. */ + uint8_t ad_extra[2]; + ad_extra[0] = (uint8_t)(in_len >> 8); + ad_extra[1] = (uint8_t)(in_len & 0xff); + MD5_Update(&md, ad_extra, sizeof(ad_extra)); + +#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, CIPHER_R_BAD_DECRYPT); + return 0; + } + + plaintext_len = in_len - rc4_ctx->tag_len; + + if (nonce_len != 0) { + OPENSSL_PUT_ERROR(CIPHER, CIPHER_R_TOO_LARGE); + return 0; + } + + if (max_out_len < in_len) { + /* This requires that the caller provide space for the MAC, even though it + * will always be removed on return. */ + OPENSSL_PUT_ERROR(CIPHER, 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); + + /* To allow for CBC mode which changes cipher length, |ad| doesn't include the + * length for legacy ciphers. */ + uint8_t ad_extra[2]; + ad_extra[0] = (uint8_t)(plaintext_len >> 8); + ad_extra[1] = (uint8_t)(plaintext_len & 0xff); + MD5_Update(&md, ad_extra, sizeof(ad_extra)); + +#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, CIPHER_R_BAD_DECRYPT); + return 0; + } + + *out_len = plaintext_len; + return 1; +} + +static int aead_rc4_md5_tls_get_rc4_state(const EVP_AEAD_CTX *ctx, + const RC4_KEY **out_key) { + struct aead_rc4_md5_tls_ctx *rc4_ctx = ctx->aead_state; + *out_key = &rc4_ctx->rc4; + 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, + NULL, /* init_with_direction */ + aead_rc4_md5_tls_cleanup, + aead_rc4_md5_tls_seal, + aead_rc4_md5_tls_open, + aead_rc4_md5_tls_get_rc4_state, +}; + +const EVP_AEAD *EVP_aead_rc4_md5_tls(void) { return &aead_rc4_md5_tls; } |