diff options
Diffstat (limited to 'core/lib/libtomcrypt/src/pk/pkcs1/pkcs_1_mgf1.c')
| -rw-r--r-- | core/lib/libtomcrypt/src/pk/pkcs1/pkcs_1_mgf1.c | 135 |
1 files changed, 135 insertions, 0 deletions
diff --git a/core/lib/libtomcrypt/src/pk/pkcs1/pkcs_1_mgf1.c b/core/lib/libtomcrypt/src/pk/pkcs1/pkcs_1_mgf1.c new file mode 100644 index 0000000..393e146 --- /dev/null +++ b/core/lib/libtomcrypt/src/pk/pkcs1/pkcs_1_mgf1.c @@ -0,0 +1,135 @@ +/* + * Copyright (c) 2001-2007, Tom St Denis + * 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. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "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 COPYRIGHT HOLDER 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. + */ + +/* LibTomCrypt, modular cryptographic library -- Tom St Denis + * + * LibTomCrypt is a library that provides various cryptographic + * algorithms in a highly modular and flexible manner. + * + * The library is free for all purposes without any express + * guarantee it works. + * + * Tom St Denis, tomstdenis@gmail.com, http://libtom.org + */ +#include "tomcrypt.h" + +/** + @file pkcs_1_mgf1.c + The Mask Generation Function (MGF1) for PKCS #1, Tom St Denis +*/ + +#ifdef LTC_PKCS_1 + +/** + Perform PKCS #1 MGF1 (internal) + @param seed The seed for MGF1 + @param seedlen The length of the seed + @param hash_idx The index of the hash desired + @param mask [out] The destination + @param masklen The length of the mask desired + @return CRYPT_OK if successful +*/ +int pkcs_1_mgf1(int hash_idx, + const unsigned char *seed, unsigned long seedlen, + unsigned char *mask, unsigned long masklen) +{ + unsigned long hLen, x; + ulong32 counter; + int err; + hash_state *md; + unsigned char *buf; + + LTC_ARGCHK(seed != NULL); + LTC_ARGCHK(mask != NULL); + + /* ensure valid hash */ + if ((err = hash_is_valid(hash_idx)) != CRYPT_OK) { + return err; + } + + /* get hash output size */ + hLen = hash_descriptor[hash_idx]->hashsize; + + /* allocate memory */ + md = XMALLOC(sizeof(hash_state)); + buf = XMALLOC(hLen); + if (md == NULL || buf == NULL) { + if (md != NULL) { + XFREE(md); + } + if (buf != NULL) { + XFREE(buf); + } + return CRYPT_MEM; + } + + /* start counter */ + counter = 0; + + while (masklen > 0) { + /* handle counter */ + STORE32H(counter, buf); + ++counter; + + /* get hash of seed || counter */ + if ((err = hash_descriptor[hash_idx]->init(md)) != CRYPT_OK) { + goto LBL_ERR; + } + if ((err = hash_descriptor[hash_idx]->process(md, seed, seedlen)) != CRYPT_OK) { + goto LBL_ERR; + } + if ((err = hash_descriptor[hash_idx]->process(md, buf, 4)) != CRYPT_OK) { + goto LBL_ERR; + } + if ((err = hash_descriptor[hash_idx]->done(md, buf)) != CRYPT_OK) { + goto LBL_ERR; + } + + /* store it */ + for (x = 0; x < hLen && masklen > 0; x++, masklen--) { + *mask++ = buf[x]; + } + } + + err = CRYPT_OK; +LBL_ERR: +#ifdef LTC_CLEAN_STACK + zeromem(buf, hLen); + zeromem(md, sizeof(hash_state)); +#endif + + XFREE(buf); + XFREE(md); + + return err; +} + +#endif /* LTC_PKCS_1 */ + +/* $Source: /cvs/libtom/libtomcrypt/src/pk/pkcs1/pkcs_1_mgf1.c,v $ */ +/* $Revision: 1.8 $ */ +/* $Date: 2007/05/12 14:32:35 $ */ |