openssl/crypto/dsa/dsa_asn1.c
TJ Saunders bbaa9dd850 Ensure that NULL r and s parameters cannot be set on DSA_SIG/ECDSA_SIGs.
Reviewed-by: Richard Levitte <levitte@openssl.org>
Reviewed-by: Emilia Käsper <emilia@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/1193)
2016-06-13 15:44:49 -04:00

141 lines
3.7 KiB
C

/*
* Copyright 1999-2016 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the OpenSSL license (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*/
#include <stdio.h>
#include "internal/cryptlib.h"
#include "dsa_locl.h"
#include <openssl/asn1.h>
#include <openssl/asn1t.h>
#include <openssl/rand.h>
struct DSA_SIG_st {
BIGNUM *r;
BIGNUM *s;
};
ASN1_SEQUENCE(DSA_SIG) = {
ASN1_SIMPLE(DSA_SIG, r, CBIGNUM),
ASN1_SIMPLE(DSA_SIG, s, CBIGNUM)
} static_ASN1_SEQUENCE_END(DSA_SIG)
IMPLEMENT_ASN1_FUNCTIONS_const(DSA_SIG)
void DSA_SIG_get0(BIGNUM **pr, BIGNUM **ps, const DSA_SIG *sig)
{
*pr = sig->r;
*ps = sig->s;
}
int DSA_SIG_set0(DSA_SIG *sig, BIGNUM *r, BIGNUM *s)
{
if (r == NULL || s == NULL)
return 0;
BN_clear_free(sig->r);
BN_clear_free(sig->s);
sig->r = r;
sig->s = s;
return 1;
}
/* Override the default free and new methods */
static int dsa_cb(int operation, ASN1_VALUE **pval, const ASN1_ITEM *it,
void *exarg)
{
if (operation == ASN1_OP_NEW_PRE) {
*pval = (ASN1_VALUE *)DSA_new();
if (*pval != NULL)
return 2;
return 0;
} else if (operation == ASN1_OP_FREE_PRE) {
DSA_free((DSA *)*pval);
*pval = NULL;
return 2;
}
return 1;
}
ASN1_SEQUENCE_cb(DSAPrivateKey, dsa_cb) = {
ASN1_SIMPLE(DSA, version, LONG),
ASN1_SIMPLE(DSA, p, BIGNUM),
ASN1_SIMPLE(DSA, q, BIGNUM),
ASN1_SIMPLE(DSA, g, BIGNUM),
ASN1_SIMPLE(DSA, pub_key, BIGNUM),
ASN1_SIMPLE(DSA, priv_key, CBIGNUM)
} static_ASN1_SEQUENCE_END_cb(DSA, DSAPrivateKey)
IMPLEMENT_ASN1_ENCODE_FUNCTIONS_const_fname(DSA, DSAPrivateKey, DSAPrivateKey)
ASN1_SEQUENCE_cb(DSAparams, dsa_cb) = {
ASN1_SIMPLE(DSA, p, BIGNUM),
ASN1_SIMPLE(DSA, q, BIGNUM),
ASN1_SIMPLE(DSA, g, BIGNUM),
} static_ASN1_SEQUENCE_END_cb(DSA, DSAparams)
IMPLEMENT_ASN1_ENCODE_FUNCTIONS_const_fname(DSA, DSAparams, DSAparams)
ASN1_SEQUENCE_cb(DSAPublicKey, dsa_cb) = {
ASN1_SIMPLE(DSA, pub_key, BIGNUM),
ASN1_SIMPLE(DSA, p, BIGNUM),
ASN1_SIMPLE(DSA, q, BIGNUM),
ASN1_SIMPLE(DSA, g, BIGNUM)
} static_ASN1_SEQUENCE_END_cb(DSA, DSAPublicKey)
IMPLEMENT_ASN1_ENCODE_FUNCTIONS_const_fname(DSA, DSAPublicKey, DSAPublicKey)
DSA *DSAparams_dup(DSA *dsa)
{
return ASN1_item_dup(ASN1_ITEM_rptr(DSAparams), dsa);
}
int DSA_sign(int type, const unsigned char *dgst, int dlen,
unsigned char *sig, unsigned int *siglen, DSA *dsa)
{
DSA_SIG *s;
RAND_seed(dgst, dlen);
s = DSA_do_sign(dgst, dlen, dsa);
if (s == NULL) {
*siglen = 0;
return (0);
}
*siglen = i2d_DSA_SIG(s, &sig);
DSA_SIG_free(s);
return (1);
}
/* data has already been hashed (probably with SHA or SHA-1). */
/*-
* returns
* 1: correct signature
* 0: incorrect signature
* -1: error
*/
int DSA_verify(int type, const unsigned char *dgst, int dgst_len,
const unsigned char *sigbuf, int siglen, DSA *dsa)
{
DSA_SIG *s;
const unsigned char *p = sigbuf;
unsigned char *der = NULL;
int derlen = -1;
int ret = -1;
s = DSA_SIG_new();
if (s == NULL)
return (ret);
if (d2i_DSA_SIG(&s, &p, siglen) == NULL)
goto err;
/* Ensure signature uses DER and doesn't have trailing garbage */
derlen = i2d_DSA_SIG(s, &der);
if (derlen != siglen || memcmp(sigbuf, der, derlen))
goto err;
ret = DSA_do_verify(dgst, dgst_len, s, dsa);
err:
OPENSSL_clear_free(der, derlen);
DSA_SIG_free(s);
return (ret);
}