/* 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 <stdio.h> #include <stdlib.h> #include <string.h> #include "internal/cryptlib.h" #include <openssl/hmac.h> #include <openssl/opensslconf.h> #include "hmac_lcl.h" int HMAC_Init_ex(HMAC_CTX *ctx, const void *key, int len, const EVP_MD *md, ENGINE *impl) { int i, j, reset = 0; unsigned char pad[HMAC_MAX_MD_CBLOCK]; /* If we are changing MD then we must have a key */ if (md != NULL && md != ctx->md && (key == NULL || len < 0)) return 0; if (md != NULL) { reset = 1; ctx->md = md; } else if (ctx->md) { md = ctx->md; } else { return 0; } if (key != NULL) { reset = 1; j = EVP_MD_block_size(md); OPENSSL_assert(j <= (int)sizeof(ctx->key)); if (j < len) { if (!EVP_DigestInit_ex(ctx->md_ctx, md, impl)) goto err; if (!EVP_DigestUpdate(ctx->md_ctx, key, len)) goto err; if (!EVP_DigestFinal_ex(ctx->md_ctx, ctx->key, &ctx->key_length)) goto err; } else { if (len < 0 || len > (int)sizeof(ctx->key)) return 0; memcpy(ctx->key, key, len); ctx->key_length = len; } if (ctx->key_length != HMAC_MAX_MD_CBLOCK) memset(&ctx->key[ctx->key_length], 0, HMAC_MAX_MD_CBLOCK - ctx->key_length); } if (reset) { for (i = 0; i < HMAC_MAX_MD_CBLOCK; i++) pad[i] = 0x36 ^ ctx->key[i]; if (!EVP_DigestInit_ex(ctx->i_ctx, md, impl)) goto err; if (!EVP_DigestUpdate(ctx->i_ctx, pad, EVP_MD_block_size(md))) goto err; for (i = 0; i < HMAC_MAX_MD_CBLOCK; i++) pad[i] = 0x5c ^ ctx->key[i]; if (!EVP_DigestInit_ex(ctx->o_ctx, md, impl)) goto err; if (!EVP_DigestUpdate(ctx->o_ctx, pad, EVP_MD_block_size(md))) goto err; } if (!EVP_MD_CTX_copy_ex(ctx->md_ctx, ctx->i_ctx)) goto err; return 1; err: return 0; } #if OPENSSL_API_COMPAT < 0x10100000L int HMAC_Init(HMAC_CTX *ctx, const void *key, int len, const EVP_MD *md) { if (key && md) HMAC_CTX_reset(ctx); return HMAC_Init_ex(ctx, key, len, md, NULL); } #endif int HMAC_Update(HMAC_CTX *ctx, const unsigned char *data, size_t len) { if (!ctx->md) return 0; return EVP_DigestUpdate(ctx->md_ctx, data, len); } int HMAC_Final(HMAC_CTX *ctx, unsigned char *md, unsigned int *len) { unsigned int i; unsigned char buf[EVP_MAX_MD_SIZE]; if (!ctx->md) goto err; if (!EVP_DigestFinal_ex(ctx->md_ctx, buf, &i)) goto err; if (!EVP_MD_CTX_copy_ex(ctx->md_ctx, ctx->o_ctx)) goto err; if (!EVP_DigestUpdate(ctx->md_ctx, buf, i)) goto err; if (!EVP_DigestFinal_ex(ctx->md_ctx, md, len)) goto err; return 1; err: return 0; } size_t HMAC_size(HMAC_CTX *ctx) { return EVP_MD_size((ctx)->md); } HMAC_CTX *HMAC_CTX_new(void) { HMAC_CTX *ctx = OPENSSL_zalloc(sizeof(HMAC_CTX)); if (ctx != NULL) { if (!HMAC_CTX_reset(ctx)) { HMAC_CTX_free(ctx); return NULL; } } return ctx; } static void hmac_ctx_cleanup(HMAC_CTX *ctx) { EVP_MD_CTX_reset(ctx->i_ctx); EVP_MD_CTX_reset(ctx->o_ctx); EVP_MD_CTX_reset(ctx->md_ctx); ctx->md = NULL; ctx->key_length = 0; memset(ctx->key, 0, sizeof(HMAC_MAX_MD_CBLOCK)); } void HMAC_CTX_free(HMAC_CTX *ctx) { if (ctx != NULL) { hmac_ctx_cleanup(ctx); EVP_MD_CTX_free(ctx->i_ctx); EVP_MD_CTX_free(ctx->o_ctx); EVP_MD_CTX_free(ctx->md_ctx); OPENSSL_free(ctx); } } int HMAC_CTX_reset(HMAC_CTX *ctx) { hmac_ctx_cleanup(ctx); if (ctx->i_ctx == NULL) ctx->i_ctx = EVP_MD_CTX_new(); if (ctx->i_ctx == NULL) goto err; if (ctx->o_ctx == NULL) ctx->o_ctx = EVP_MD_CTX_new(); if (ctx->o_ctx == NULL) goto err; if (ctx->md_ctx == NULL) ctx->md_ctx = EVP_MD_CTX_new(); if (ctx->md_ctx == NULL) goto err; ctx->md = NULL; return 1; err: hmac_ctx_cleanup(ctx); return 0; } int HMAC_CTX_copy(HMAC_CTX *dctx, HMAC_CTX *sctx) { if (!HMAC_CTX_reset(dctx)) goto err; if (!EVP_MD_CTX_copy_ex(dctx->i_ctx, sctx->i_ctx)) goto err; if (!EVP_MD_CTX_copy_ex(dctx->o_ctx, sctx->o_ctx)) goto err; if (!EVP_MD_CTX_copy_ex(dctx->md_ctx, sctx->md_ctx)) goto err; memcpy(dctx->key, sctx->key, HMAC_MAX_MD_CBLOCK); dctx->key_length = sctx->key_length; dctx->md = sctx->md; return 1; err: hmac_ctx_cleanup(dctx); return 0; } unsigned char *HMAC(const EVP_MD *evp_md, const void *key, int key_len, const unsigned char *d, size_t n, unsigned char *md, unsigned int *md_len) { HMAC_CTX *c = NULL; static unsigned char m[EVP_MAX_MD_SIZE]; static const unsigned char dummy_key[1] = {'\0'}; if (md == NULL) md = m; if ((c = HMAC_CTX_new()) == NULL) goto err; /* For HMAC_Init_ex, NULL key signals reuse. */ if (key == NULL && key_len == 0) { key = dummy_key; } if (!HMAC_Init_ex(c, key, key_len, evp_md, NULL)) goto err; if (!HMAC_Update(c, d, n)) goto err; if (!HMAC_Final(c, md, md_len)) goto err; HMAC_CTX_free(c); return md; err: HMAC_CTX_free(c); return NULL; } void HMAC_CTX_set_flags(HMAC_CTX *ctx, unsigned long flags) { EVP_MD_CTX_set_flags(ctx->i_ctx, flags); EVP_MD_CTX_set_flags(ctx->o_ctx, flags); EVP_MD_CTX_set_flags(ctx->md_ctx, flags); }