1109998Smarkm/* dsa_asn1.c */ 2280297Sjkim/* 3280297Sjkim * Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL project 4280297Sjkim * 2000. 5109998Smarkm */ 6109998Smarkm/* ==================================================================== 7238405Sjkim * Copyright (c) 2000-2005 The OpenSSL Project. All rights reserved. 8109998Smarkm * 9109998Smarkm * Redistribution and use in source and binary forms, with or without 10109998Smarkm * modification, are permitted provided that the following conditions 11109998Smarkm * are met: 12109998Smarkm * 13109998Smarkm * 1. Redistributions of source code must retain the above copyright 14280297Sjkim * notice, this list of conditions and the following disclaimer. 15109998Smarkm * 16109998Smarkm * 2. Redistributions in binary form must reproduce the above copyright 17109998Smarkm * notice, this list of conditions and the following disclaimer in 18109998Smarkm * the documentation and/or other materials provided with the 19109998Smarkm * distribution. 20109998Smarkm * 21109998Smarkm * 3. All advertising materials mentioning features or use of this 22109998Smarkm * software must display the following acknowledgment: 23109998Smarkm * "This product includes software developed by the OpenSSL Project 24109998Smarkm * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)" 25109998Smarkm * 26109998Smarkm * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to 27109998Smarkm * endorse or promote products derived from this software without 28109998Smarkm * prior written permission. For written permission, please contact 29109998Smarkm * licensing@OpenSSL.org. 30109998Smarkm * 31109998Smarkm * 5. Products derived from this software may not be called "OpenSSL" 32109998Smarkm * nor may "OpenSSL" appear in their names without prior written 33109998Smarkm * permission of the OpenSSL Project. 34109998Smarkm * 35109998Smarkm * 6. Redistributions of any form whatsoever must retain the following 36109998Smarkm * acknowledgment: 37109998Smarkm * "This product includes software developed by the OpenSSL Project 38109998Smarkm * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)" 39109998Smarkm * 40109998Smarkm * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY 41109998Smarkm * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 42109998Smarkm * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 43109998Smarkm * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR 44109998Smarkm * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 45109998Smarkm * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 46109998Smarkm * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 47109998Smarkm * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 48109998Smarkm * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 49109998Smarkm * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 50109998Smarkm * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 51109998Smarkm * OF THE POSSIBILITY OF SUCH DAMAGE. 52109998Smarkm * ==================================================================== 53109998Smarkm * 54109998Smarkm * This product includes cryptographic software written by Eric Young 55109998Smarkm * (eay@cryptsoft.com). This product includes software written by Tim 56109998Smarkm * Hudson (tjh@cryptsoft.com). 57109998Smarkm * 58109998Smarkm */ 5955714Skris 6055714Skris#include <stdio.h> 6155714Skris#include "cryptlib.h" 6255714Skris#include <openssl/dsa.h> 6355714Skris#include <openssl/asn1.h> 64109998Smarkm#include <openssl/asn1t.h> 65205128Ssimon#include <openssl/rand.h> 6655714Skris 67109998Smarkm/* Override the default new methods */ 68238405Sjkimstatic int sig_cb(int operation, ASN1_VALUE **pval, const ASN1_ITEM *it, 69280297Sjkim void *exarg) 7055714Skris{ 71280297Sjkim if (operation == ASN1_OP_NEW_PRE) { 72280297Sjkim DSA_SIG *sig; 73280297Sjkim sig = OPENSSL_malloc(sizeof(DSA_SIG)); 74280297Sjkim if (!sig) { 75280297Sjkim DSAerr(DSA_F_SIG_CB, ERR_R_MALLOC_FAILURE); 76280297Sjkim return 0; 77280297Sjkim } 78280297Sjkim sig->r = NULL; 79280297Sjkim sig->s = NULL; 80280297Sjkim *pval = (ASN1_VALUE *)sig; 81280297Sjkim return 2; 82280297Sjkim } 83280297Sjkim return 1; 8455714Skris} 8555714Skris 86109998SmarkmASN1_SEQUENCE_cb(DSA_SIG, sig_cb) = { 87280297Sjkim ASN1_SIMPLE(DSA_SIG, r, CBIGNUM), 88280297Sjkim ASN1_SIMPLE(DSA_SIG, s, CBIGNUM) 89109998Smarkm} ASN1_SEQUENCE_END_cb(DSA_SIG, DSA_SIG) 90109998Smarkm 91238405SjkimIMPLEMENT_ASN1_ENCODE_FUNCTIONS_const_fname(DSA_SIG, DSA_SIG, DSA_SIG) 92109998Smarkm 93109998Smarkm/* Override the default free and new methods */ 94238405Sjkimstatic int dsa_cb(int operation, ASN1_VALUE **pval, const ASN1_ITEM *it, 95280297Sjkim void *exarg) 9655714Skris{ 97280297Sjkim if (operation == ASN1_OP_NEW_PRE) { 98280297Sjkim *pval = (ASN1_VALUE *)DSA_new(); 99280297Sjkim if (*pval) 100280297Sjkim return 2; 101280297Sjkim return 0; 102280297Sjkim } else if (operation == ASN1_OP_FREE_PRE) { 103280297Sjkim DSA_free((DSA *)*pval); 104280297Sjkim *pval = NULL; 105280297Sjkim return 2; 106280297Sjkim } 107280297Sjkim return 1; 10855714Skris} 10955714Skris 110109998SmarkmASN1_SEQUENCE_cb(DSAPrivateKey, dsa_cb) = { 111280297Sjkim ASN1_SIMPLE(DSA, version, LONG), 112280297Sjkim ASN1_SIMPLE(DSA, p, BIGNUM), 113280297Sjkim ASN1_SIMPLE(DSA, q, BIGNUM), 114280297Sjkim ASN1_SIMPLE(DSA, g, BIGNUM), 115280297Sjkim ASN1_SIMPLE(DSA, pub_key, BIGNUM), 116280297Sjkim ASN1_SIMPLE(DSA, priv_key, BIGNUM) 117109998Smarkm} ASN1_SEQUENCE_END_cb(DSA, DSAPrivateKey) 11855714Skris 119109998SmarkmIMPLEMENT_ASN1_ENCODE_FUNCTIONS_const_fname(DSA, DSAPrivateKey, DSAPrivateKey) 12055714Skris 121109998SmarkmASN1_SEQUENCE_cb(DSAparams, dsa_cb) = { 122280297Sjkim ASN1_SIMPLE(DSA, p, BIGNUM), 123280297Sjkim ASN1_SIMPLE(DSA, q, BIGNUM), 124280297Sjkim ASN1_SIMPLE(DSA, g, BIGNUM), 125109998Smarkm} ASN1_SEQUENCE_END_cb(DSA, DSAparams) 12655714Skris 127109998SmarkmIMPLEMENT_ASN1_ENCODE_FUNCTIONS_const_fname(DSA, DSAparams, DSAparams) 12855714Skris 129280297Sjkim/* 130280297Sjkim * DSA public key is a bit trickier... its effectively a CHOICE type decided 131280297Sjkim * by a field called write_params which can either write out just the public 132280297Sjkim * key as an INTEGER or the parameters and public key in a SEQUENCE 133109998Smarkm */ 13455714Skris 135109998SmarkmASN1_SEQUENCE(dsa_pub_internal) = { 136280297Sjkim ASN1_SIMPLE(DSA, pub_key, BIGNUM), 137280297Sjkim ASN1_SIMPLE(DSA, p, BIGNUM), 138280297Sjkim ASN1_SIMPLE(DSA, q, BIGNUM), 139280297Sjkim ASN1_SIMPLE(DSA, g, BIGNUM) 140109998Smarkm} ASN1_SEQUENCE_END_name(DSA, dsa_pub_internal) 14155714Skris 142109998SmarkmASN1_CHOICE_cb(DSAPublicKey, dsa_cb) = { 143280297Sjkim ASN1_SIMPLE(DSA, pub_key, BIGNUM), 144280297Sjkim ASN1_EX_COMBINE(0, 0, dsa_pub_internal) 145109998Smarkm} ASN1_CHOICE_END_cb(DSA, DSAPublicKey, write_params) 146109998Smarkm 147109998SmarkmIMPLEMENT_ASN1_ENCODE_FUNCTIONS_const_fname(DSA, DSAPublicKey, DSAPublicKey) 148194206Ssimon 149238405SjkimDSA *DSAparams_dup(DSA *dsa) 150280297Sjkim{ 151280297Sjkim return ASN1_item_dup(ASN1_ITEM_rptr(DSAparams), dsa); 152280297Sjkim} 153238405Sjkim 154280297Sjkimint DSA_sign(int type, const unsigned char *dgst, int dlen, 155280297Sjkim unsigned char *sig, unsigned int *siglen, DSA *dsa) 156280297Sjkim{ 157280297Sjkim DSA_SIG *s; 158280297Sjkim RAND_seed(dgst, dlen); 159280297Sjkim s = DSA_do_sign(dgst, dlen, dsa); 160280297Sjkim if (s == NULL) { 161280297Sjkim *siglen = 0; 162280297Sjkim return (0); 163280297Sjkim } 164280297Sjkim *siglen = i2d_DSA_SIG(s, &sig); 165280297Sjkim DSA_SIG_free(s); 166280297Sjkim return (1); 167280297Sjkim} 168194206Ssimon 169194206Ssimon/* data has already been hashed (probably with SHA or SHA-1). */ 170280297Sjkim/*- 171280297Sjkim * returns 172194206Ssimon * 1: correct signature 173194206Ssimon * 0: incorrect signature 174194206Ssimon * -1: error 175194206Ssimon */ 176194206Ssimonint DSA_verify(int type, const unsigned char *dgst, int dgst_len, 177280297Sjkim const unsigned char *sigbuf, int siglen, DSA *dsa) 178280297Sjkim{ 179280297Sjkim DSA_SIG *s; 180280297Sjkim const unsigned char *p = sigbuf; 181280297Sjkim unsigned char *der = NULL; 182280297Sjkim int derlen = -1; 183280297Sjkim int ret = -1; 184194206Ssimon 185280297Sjkim s = DSA_SIG_new(); 186280297Sjkim if (s == NULL) 187280297Sjkim return (ret); 188280297Sjkim if (d2i_DSA_SIG(&s, &p, siglen) == NULL) 189280297Sjkim goto err; 190280297Sjkim /* Ensure signature uses DER and doesn't have trailing garbage */ 191280297Sjkim derlen = i2d_DSA_SIG(s, &der); 192280297Sjkim if (derlen != siglen || memcmp(sigbuf, der, derlen)) 193280297Sjkim goto err; 194280297Sjkim ret = DSA_do_verify(dgst, dgst_len, s, dsa); 195280297Sjkim err: 196280297Sjkim if (derlen > 0) { 197280297Sjkim OPENSSL_cleanse(der, derlen); 198280297Sjkim OPENSSL_free(der); 199280297Sjkim } 200280297Sjkim DSA_SIG_free(s); 201280297Sjkim return (ret); 202280297Sjkim} 203