--- /dev/null
+/* crypto/cmac/cmac.c */
+/* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
+ * project.
+ */
+/* ====================================================================
+ * Copyright (c) 2010 The OpenSSL Project. All rights reserved.
+ *
+ * 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 above 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 acknowledgment:
+ * "This product includes software developed by the OpenSSL Project
+ * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
+ *
+ * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
+ * endorse or promote products derived from this software without
+ * prior written permission. For written permission, please contact
+ * licensing@OpenSSL.org.
+ *
+ * 5. Products derived from this software may not be called "OpenSSL"
+ * nor may "OpenSSL" appear in their names without prior written
+ * permission of the OpenSSL Project.
+ *
+ * 6. Redistributions of any form whatsoever must retain the following
+ * acknowledgment:
+ * "This product includes software developed by the OpenSSL Project
+ * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
+ * EXPRESSED 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 OpenSSL PROJECT OR
+ * ITS 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.
+ * ====================================================================
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "cryptlib.h"
+#include <openssl/cmac.h>
+
+#ifdef OPENSSL_FIPS
+#include <openssl/fips.h>
+#endif
+
+struct CMAC_CTX_st
+ {
+ /* Cipher context to use */
+ EVP_CIPHER_CTX cctx;
+ /* Keys k1 and k2 */
+ unsigned char k1[EVP_MAX_BLOCK_LENGTH];
+ unsigned char k2[EVP_MAX_BLOCK_LENGTH];
+ /* Temporary block */
+ unsigned char tbl[EVP_MAX_BLOCK_LENGTH];
+ /* Last (possibly partial) block */
+ unsigned char last_block[EVP_MAX_BLOCK_LENGTH];
+ /* Number of bytes in last block: -1 means context not initialised */
+ int nlast_block;
+ };
+
+
+/* Make temporary keys K1 and K2 */
+
+static void make_kn(unsigned char *k1, unsigned char *l, int bl)
+ {
+ int i;
+ /* Shift block to left, including carry */
+ for (i = 0; i < bl; i++)
+ {
+ k1[i] = l[i] << 1;
+ if (i < bl - 1 && l[i + 1] & 0x80)
+ k1[i] |= 1;
+ }
+ /* If MSB set fixup with R */
+ if (l[0] & 0x80)
+ k1[bl - 1] ^= bl == 16 ? 0x87 : 0x1b;
+ }
+
+CMAC_CTX *CMAC_CTX_new(void)
+ {
+ CMAC_CTX *ctx;
+ ctx = OPENSSL_malloc(sizeof(CMAC_CTX));
+ if (!ctx)
+ return NULL;
+ EVP_CIPHER_CTX_init(&ctx->cctx);
+ ctx->nlast_block = -1;
+ return ctx;
+ }
+
+void CMAC_CTX_cleanup(CMAC_CTX *ctx)
+ {
+#ifdef OPENSSL_FIPS
+ if (FIPS_mode() && !ctx->cctx.engine)
+ {
+ FIPS_cmac_ctx_cleanup(ctx);
+ return;
+ }
+#endif
+ EVP_CIPHER_CTX_cleanup(&ctx->cctx);
+ OPENSSL_cleanse(ctx->tbl, EVP_MAX_BLOCK_LENGTH);
+ OPENSSL_cleanse(ctx->k1, EVP_MAX_BLOCK_LENGTH);
+ OPENSSL_cleanse(ctx->k2, EVP_MAX_BLOCK_LENGTH);
+ OPENSSL_cleanse(ctx->last_block, EVP_MAX_BLOCK_LENGTH);
+ ctx->nlast_block = -1;
+ }
+
+EVP_CIPHER_CTX *CMAC_CTX_get0_cipher_ctx(CMAC_CTX *ctx)
+ {
+ return &ctx->cctx;
+ }
+
+void CMAC_CTX_free(CMAC_CTX *ctx)
+ {
+ CMAC_CTX_cleanup(ctx);
+ OPENSSL_free(ctx);
+ }
+
+int CMAC_CTX_copy(CMAC_CTX *out, const CMAC_CTX *in)
+ {
+ int bl;
+ if (in->nlast_block == -1)
+ return 0;
+ if (!EVP_CIPHER_CTX_copy(&out->cctx, &in->cctx))
+ return 0;
+ bl = EVP_CIPHER_CTX_block_size(&in->cctx);
+ memcpy(out->k1, in->k1, bl);
+ memcpy(out->k2, in->k2, bl);
+ memcpy(out->tbl, in->tbl, bl);
+ memcpy(out->last_block, in->last_block, bl);
+ out->nlast_block = in->nlast_block;
+ return 1;
+ }
+
+int CMAC_Init(CMAC_CTX *ctx, const void *key, size_t keylen,
+ const EVP_CIPHER *cipher, ENGINE *impl)
+ {
+ static unsigned char zero_iv[EVP_MAX_BLOCK_LENGTH];
+#ifdef OPENSSL_FIPS
+ if (FIPS_mode())
+ {
+ /* If we have an ENGINE need to allow non FIPS */
+ if ((impl || ctx->cctx.engine)
+ && !(ctx->cctx.flags & EVP_CIPH_FLAG_NON_FIPS_ALLOW))
+
+ {
+ EVPerr(EVP_F_CMAC_INIT, EVP_R_DISABLED_FOR_FIPS);
+ return 0;
+ }
+ /* Other algorithm blocking will be done in FIPS_cmac_init,
+ * via FIPS_cipherinit().
+ */
+ if (!impl && !ctx->cctx.engine)
+ return FIPS_cmac_init(ctx, key, keylen, cipher, NULL);
+ }
+#endif
+ /* All zeros means restart */
+ if (!key && !cipher && !impl && keylen == 0)
+ {
+ /* Not initialised */
+ if (ctx->nlast_block == -1)
+ return 0;
+ if (!EVP_EncryptInit_ex(&ctx->cctx, NULL, NULL, NULL, zero_iv))
+ return 0;
+ memset(ctx->tbl, 0, EVP_CIPHER_CTX_block_size(&ctx->cctx));
+ ctx->nlast_block = 0;
+ return 1;
+ }
+ /* Initialiase context */
+ if (cipher && !EVP_EncryptInit_ex(&ctx->cctx, cipher, impl, NULL, NULL))
+ return 0;
+ /* Non-NULL key means initialisation complete */
+ if (key)
+ {
+ int bl;
+ if (!EVP_CIPHER_CTX_cipher(&ctx->cctx))
+ return 0;
+ if (!EVP_CIPHER_CTX_set_key_length(&ctx->cctx, keylen))
+ return 0;
+ if (!EVP_EncryptInit_ex(&ctx->cctx, NULL, NULL, key, zero_iv))
+ return 0;
+ bl = EVP_CIPHER_CTX_block_size(&ctx->cctx);
+ if (!EVP_Cipher(&ctx->cctx, ctx->tbl, zero_iv, bl))
+ return 0;
+ make_kn(ctx->k1, ctx->tbl, bl);
+ make_kn(ctx->k2, ctx->k1, bl);
+ OPENSSL_cleanse(ctx->tbl, bl);
+ /* Reset context again ready for first data block */
+ if (!EVP_EncryptInit_ex(&ctx->cctx, NULL, NULL, NULL, zero_iv))
+ return 0;
+ /* Zero tbl so resume works */
+ memset(ctx->tbl, 0, bl);
+ ctx->nlast_block = 0;
+ }
+ return 1;
+ }
+
+int CMAC_Update(CMAC_CTX *ctx, const void *in, size_t dlen)
+ {
+ const unsigned char *data = in;
+ size_t bl;
+#ifdef OPENSSL_FIPS
+ if (FIPS_mode() && !ctx->cctx.engine)
+ return FIPS_cmac_update(ctx, in, dlen);
+#endif
+ if (ctx->nlast_block == -1)
+ return 0;
+ if (dlen == 0)
+ return 1;
+ bl = EVP_CIPHER_CTX_block_size(&ctx->cctx);
+ /* Copy into partial block if we need to */
+ if (ctx->nlast_block > 0)
+ {
+ size_t nleft;
+ nleft = bl - ctx->nlast_block;
+ if (dlen < nleft)
+ nleft = dlen;
+ memcpy(ctx->last_block + ctx->nlast_block, data, nleft);
+ dlen -= nleft;
+ ctx->nlast_block += nleft;
+ /* If no more to process return */
+ if (dlen == 0)
+ return 1;
+ data += nleft;
+ /* Else not final block so encrypt it */
+ if (!EVP_Cipher(&ctx->cctx, ctx->tbl, ctx->last_block,bl))
+ return 0;
+ }
+ /* Encrypt all but one of the complete blocks left */
+ while(dlen > bl)
+ {
+ if (!EVP_Cipher(&ctx->cctx, ctx->tbl, data, bl))
+ return 0;
+ dlen -= bl;
+ data += bl;
+ }
+ /* Copy any data left to last block buffer */
+ memcpy(ctx->last_block, data, dlen);
+ ctx->nlast_block = dlen;
+ return 1;
+
+ }
+
+int CMAC_Final(CMAC_CTX *ctx, unsigned char *out, size_t *poutlen)
+ {
+ int i, bl, lb;
+#ifdef OPENSSL_FIPS
+ if (FIPS_mode() && !ctx->cctx.engine)
+ return FIPS_cmac_final(ctx, out, poutlen);
+#endif
+ if (ctx->nlast_block == -1)
+ return 0;
+ bl = EVP_CIPHER_CTX_block_size(&ctx->cctx);
+ *poutlen = (size_t)bl;
+ if (!out)
+ return 1;
+ lb = ctx->nlast_block;
+ /* Is last block complete? */
+ if (lb == bl)
+ {
+ for (i = 0; i < bl; i++)
+ out[i] = ctx->last_block[i] ^ ctx->k1[i];
+ }
+ else
+ {
+ ctx->last_block[lb] = 0x80;
+ if (bl - lb > 1)
+ memset(ctx->last_block + lb + 1, 0, bl - lb - 1);
+ for (i = 0; i < bl; i++)
+ out[i] = ctx->last_block[i] ^ ctx->k2[i];
+ }
+ if (!EVP_Cipher(&ctx->cctx, out, out, bl))
+ {
+ OPENSSL_cleanse(out, bl);
+ return 0;
+ }
+ return 1;
+ }
+
+int CMAC_resume(CMAC_CTX *ctx)
+ {
+ if (ctx->nlast_block == -1)
+ return 0;
+ /* The buffer "tbl" containes the last fully encrypted block
+ * which is the last IV (or all zeroes if no last encrypted block).
+ * The last block has not been modified since CMAC_final().
+ * So reinitliasing using the last decrypted block will allow
+ * CMAC to continue after calling CMAC_Final().
+ */
+ return EVP_EncryptInit_ex(&ctx->cctx, NULL, NULL, NULL, ctx->tbl);
+ }
projects / cassiopeia.git / blobdiff