/* p5_crpt2.c */ /* Written by Dr Stephen N Henson (shenson@bigfoot.com) for the OpenSSL * project 1999. */ /* ==================================================================== * Copyright (c) 1999 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. * ==================================================================== * * This product includes cryptographic software written by Eric Young * (eay@cryptsoft.com). This product includes software written by Tim * Hudson (tjh@cryptsoft.com). * */ #include #include #include #include #include #include "cryptlib.h" /* set this to print out info about the keygen algorithm */ /* #define DEBUG_PKCS5V2 */ #ifdef DEBUG_PKCS5V2 static void h__dump (const unsigned char *p, int len); #endif /* This is an implementation of PKCS#5 v2.0 password based encryption key * derivation function PBKDF2 using the only currently defined function HMAC * with SHA1. Verified against test vectors posted by Peter Gutmann * to the PKCS-TNG mailing list. */ int PKCS5_PBKDF2_HMAC_SHA1(const char *pass, int passlen, unsigned char *salt, int saltlen, int iter, int keylen, unsigned char *out) { unsigned char digtmp[SHA_DIGEST_LENGTH], *p, itmp[4]; int cplen, j, k, tkeylen; unsigned long i = 1; HMAC_CTX hctx; p = out; tkeylen = keylen; if(passlen == -1) passlen = strlen(pass); while(tkeylen) { if(tkeylen > SHA_DIGEST_LENGTH) cplen = SHA_DIGEST_LENGTH; else cplen = tkeylen; /* We are unlikely to ever use more than 256 blocks (5120 bits!) * but just in case... */ itmp[0] = (unsigned char)((i >> 24) & 0xff); itmp[1] = (unsigned char)((i >> 16) & 0xff); itmp[2] = (unsigned char)((i >> 8) & 0xff); itmp[3] = (unsigned char)(i & 0xff); HMAC_Init(&hctx, pass, passlen, EVP_sha1()); HMAC_Update(&hctx, salt, saltlen); HMAC_Update(&hctx, itmp, 4); HMAC_Final(&hctx, digtmp, NULL); memcpy(p, digtmp, cplen); for(j = 1; j < iter; j++) { HMAC(EVP_sha1(), pass, passlen, digtmp, SHA_DIGEST_LENGTH, digtmp, NULL); for(k = 0; k < cplen; k++) p[k] ^= digtmp[k]; } tkeylen-= cplen; i++; p+= cplen; } HMAC_cleanup(&hctx); #ifdef DEBUG_PKCS5V2 fprintf(stderr, "Password:\n"); h__dump (pass, passlen); fprintf(stderr, "Salt:\n"); h__dump (salt, saltlen); fprintf(stderr, "Iteration count %d\n", iter); fprintf(stderr, "Key:\n"); h__dump (out, keylen); #endif return 1; } #ifdef DO_TEST main() { unsigned char out[4]; unsigned char salt[] = {0x12, 0x34, 0x56, 0x78}; PKCS5_PBKDF2_HMAC_SHA1("password", -1, salt, 4, 5, 4, out); fprintf(stderr, "Out %02X %02X %02X %02X\n", out[0], out[1], out[2], out[3]); } #endif /* Now the key derivation function itself. This is a bit evil because * it has to check the ASN1 parameters are valid: and there are quite a * few of them... */ int PKCS5_v2_PBE_keyivgen(EVP_CIPHER_CTX *ctx, const char *pass, int passlen, ASN1_TYPE *param, EVP_CIPHER *c, EVP_MD *md, int en_de) { unsigned char *pbuf, *salt, key[EVP_MAX_KEY_LENGTH]; int saltlen, keylen, iter, plen; PBE2PARAM *pbe2 = NULL; const EVP_CIPHER *cipher; PBKDF2PARAM *kdf = NULL; pbuf = param->value.sequence->data; plen = param->value.sequence->length; if(!param || (param->type != V_ASN1_SEQUENCE) || !(pbe2 = d2i_PBE2PARAM(NULL, &pbuf, plen))) { EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN,EVP_R_DECODE_ERROR); return 0; } /* See if we recognise the key derivation function */ if(OBJ_obj2nid(pbe2->keyfunc->algorithm) != NID_id_pbkdf2) { EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN, EVP_R_UNSUPPORTED_KEY_DERIVATION_FUNCTION); goto err; } /* lets see if we recognise the encryption algorithm. */ cipher = EVP_get_cipherbyname( OBJ_nid2sn(OBJ_obj2nid(pbe2->encryption->algorithm))); if(!cipher) { EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN, EVP_R_UNSUPPORTED_CIPHER); goto err; } /* Fixup cipher based on AlgorithmIdentifier */ EVP_CipherInit(ctx, cipher, NULL, NULL, en_de); if(EVP_CIPHER_asn1_to_param(ctx, pbe2->encryption->parameter) < 0) { EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN, EVP_R_CIPHER_PARAMETER_ERROR); goto err; } keylen = EVP_CIPHER_CTX_key_length(ctx); /* Now decode key derivation function */ pbuf = pbe2->keyfunc->parameter->value.sequence->data; plen = pbe2->keyfunc->parameter->value.sequence->length; if(!pbe2->keyfunc->parameter || (pbe2->keyfunc->parameter->type != V_ASN1_SEQUENCE) || !(kdf = d2i_PBKDF2PARAM(NULL, &pbuf, plen)) ) { EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN,EVP_R_DECODE_ERROR); goto err; } PBE2PARAM_free(pbe2); pbe2 = NULL; /* Now check the parameters of the kdf */ if(kdf->keylength && (ASN1_INTEGER_get(kdf->keylength) != keylen)){ EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN, EVP_R_UNSUPPORTED_KEYLENGTH); goto err; } if(kdf->prf && (OBJ_obj2nid(kdf->prf->algorithm) != NID_hmacWithSHA1)) { EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN, EVP_R_UNSUPPORTED_PRF); goto err; } if(kdf->salt->type != V_ASN1_OCTET_STRING) { EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN, EVP_R_UNSUPPORTED_SALT_TYPE); goto err; } /* it seems that its all OK */ salt = kdf->salt->value.octet_string->data; saltlen = kdf->salt->value.octet_string->length; iter = ASN1_INTEGER_get(kdf->iter); PKCS5_PBKDF2_HMAC_SHA1(pass, passlen, salt, saltlen, iter, keylen, key); EVP_CipherInit(ctx, NULL, key, NULL, en_de); memset(key, 0, keylen); PBKDF2PARAM_free(kdf); return 1; err: PBE2PARAM_free(pbe2); PBKDF2PARAM_free(kdf); return 0; } #ifdef DEBUG_PKCS5V2 static void h__dump (const unsigned char *p, int len) { for (; len --; p++) fprintf(stderr, "%02X ", *p); fprintf(stderr, "\n"); } #endif