openssl/crypto/dsa/dsa_pmeth.c
Richard Levitte 8a05c4d3b5 Fix DSA parameter generation control error
When setting the digest parameter for DSA parameter generation, the
signature MD was set instead of the parameter generation one.
Fortunately, that's also the one that was used for parameter
generation, but it ultimately meant the parameter generator MD and the
signature MD would always be the same.

Fixes github issue #2016

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2250)
2017-01-20 08:29:46 +01:00

273 lines
6.9 KiB
C

/*
* Copyright 2006-2016 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 <openssl/asn1t.h>
#include <openssl/x509.h>
#include <openssl/evp.h>
#include <openssl/bn.h>
#include "internal/evp_int.h"
#include "dsa_locl.h"
/* DSA pkey context structure */
typedef struct {
/* Parameter gen parameters */
int nbits; /* size of p in bits (default: 1024) */
int qbits; /* size of q in bits (default: 160) */
const EVP_MD *pmd; /* MD for parameter generation */
/* Keygen callback info */
int gentmp[2];
/* message digest */
const EVP_MD *md; /* MD for the signature */
} DSA_PKEY_CTX;
static int pkey_dsa_init(EVP_PKEY_CTX *ctx)
{
DSA_PKEY_CTX *dctx;
dctx = OPENSSL_malloc(sizeof(*dctx));
if (dctx == NULL)
return 0;
dctx->nbits = 1024;
dctx->qbits = 160;
dctx->pmd = NULL;
dctx->md = NULL;
ctx->data = dctx;
ctx->keygen_info = dctx->gentmp;
ctx->keygen_info_count = 2;
return 1;
}
static int pkey_dsa_copy(EVP_PKEY_CTX *dst, EVP_PKEY_CTX *src)
{
DSA_PKEY_CTX *dctx, *sctx;
if (!pkey_dsa_init(dst))
return 0;
sctx = src->data;
dctx = dst->data;
dctx->nbits = sctx->nbits;
dctx->qbits = sctx->qbits;
dctx->pmd = sctx->pmd;
dctx->md = sctx->md;
return 1;
}
static void pkey_dsa_cleanup(EVP_PKEY_CTX *ctx)
{
DSA_PKEY_CTX *dctx = ctx->data;
OPENSSL_free(dctx);
}
static int pkey_dsa_sign(EVP_PKEY_CTX *ctx, unsigned char *sig,
size_t *siglen, const unsigned char *tbs,
size_t tbslen)
{
int ret;
unsigned int sltmp;
DSA_PKEY_CTX *dctx = ctx->data;
DSA *dsa = ctx->pkey->pkey.dsa;
if (dctx->md) {
if (tbslen != (size_t)EVP_MD_size(dctx->md))
return 0;
} else {
if (tbslen != SHA_DIGEST_LENGTH)
return 0;
}
ret = DSA_sign(0, tbs, tbslen, sig, &sltmp, dsa);
if (ret <= 0)
return ret;
*siglen = sltmp;
return 1;
}
static int pkey_dsa_verify(EVP_PKEY_CTX *ctx,
const unsigned char *sig, size_t siglen,
const unsigned char *tbs, size_t tbslen)
{
int ret;
DSA_PKEY_CTX *dctx = ctx->data;
DSA *dsa = ctx->pkey->pkey.dsa;
if (dctx->md) {
if (tbslen != (size_t)EVP_MD_size(dctx->md))
return 0;
} else {
if (tbslen != SHA_DIGEST_LENGTH)
return 0;
}
ret = DSA_verify(0, tbs, tbslen, sig, siglen, dsa);
return ret;
}
static int pkey_dsa_ctrl(EVP_PKEY_CTX *ctx, int type, int p1, void *p2)
{
DSA_PKEY_CTX *dctx = ctx->data;
switch (type) {
case EVP_PKEY_CTRL_DSA_PARAMGEN_BITS:
if (p1 < 256)
return -2;
dctx->nbits = p1;
return 1;
case EVP_PKEY_CTRL_DSA_PARAMGEN_Q_BITS:
if (p1 != 160 && p1 != 224 && p1 && p1 != 256)
return -2;
dctx->qbits = p1;
return 1;
case EVP_PKEY_CTRL_DSA_PARAMGEN_MD:
if (EVP_MD_type((const EVP_MD *)p2) != NID_sha1 &&
EVP_MD_type((const EVP_MD *)p2) != NID_sha224 &&
EVP_MD_type((const EVP_MD *)p2) != NID_sha256) {
DSAerr(DSA_F_PKEY_DSA_CTRL, DSA_R_INVALID_DIGEST_TYPE);
return 0;
}
dctx->pmd = p2;
return 1;
case EVP_PKEY_CTRL_MD:
if (EVP_MD_type((const EVP_MD *)p2) != NID_sha1 &&
EVP_MD_type((const EVP_MD *)p2) != NID_dsa &&
EVP_MD_type((const EVP_MD *)p2) != NID_dsaWithSHA &&
EVP_MD_type((const EVP_MD *)p2) != NID_sha224 &&
EVP_MD_type((const EVP_MD *)p2) != NID_sha256 &&
EVP_MD_type((const EVP_MD *)p2) != NID_sha384 &&
EVP_MD_type((const EVP_MD *)p2) != NID_sha512) {
DSAerr(DSA_F_PKEY_DSA_CTRL, DSA_R_INVALID_DIGEST_TYPE);
return 0;
}
dctx->md = p2;
return 1;
case EVP_PKEY_CTRL_GET_MD:
*(const EVP_MD **)p2 = dctx->md;
return 1;
case EVP_PKEY_CTRL_DIGESTINIT:
case EVP_PKEY_CTRL_PKCS7_SIGN:
case EVP_PKEY_CTRL_CMS_SIGN:
return 1;
case EVP_PKEY_CTRL_PEER_KEY:
DSAerr(DSA_F_PKEY_DSA_CTRL,
EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
return -2;
default:
return -2;
}
}
static int pkey_dsa_ctrl_str(EVP_PKEY_CTX *ctx,
const char *type, const char *value)
{
if (strcmp(type, "dsa_paramgen_bits") == 0) {
int nbits;
nbits = atoi(value);
return EVP_PKEY_CTX_set_dsa_paramgen_bits(ctx, nbits);
}
if (strcmp(type, "dsa_paramgen_q_bits") == 0) {
int qbits = atoi(value);
return EVP_PKEY_CTX_ctrl(ctx, EVP_PKEY_DSA, EVP_PKEY_OP_PARAMGEN,
EVP_PKEY_CTRL_DSA_PARAMGEN_Q_BITS, qbits,
NULL);
}
if (strcmp(type, "dsa_paramgen_md") == 0) {
return EVP_PKEY_CTX_ctrl(ctx, EVP_PKEY_DSA, EVP_PKEY_OP_PARAMGEN,
EVP_PKEY_CTRL_DSA_PARAMGEN_MD, 0,
(void *)EVP_get_digestbyname(value));
}
return -2;
}
static int pkey_dsa_paramgen(EVP_PKEY_CTX *ctx, EVP_PKEY *pkey)
{
DSA *dsa = NULL;
DSA_PKEY_CTX *dctx = ctx->data;
BN_GENCB *pcb;
int ret;
if (ctx->pkey_gencb) {
pcb = BN_GENCB_new();
if (pcb == NULL)
return 0;
evp_pkey_set_cb_translate(pcb, ctx);
} else
pcb = NULL;
dsa = DSA_new();
if (dsa == NULL) {
BN_GENCB_free(pcb);
return 0;
}
ret = dsa_builtin_paramgen(dsa, dctx->nbits, dctx->qbits, dctx->pmd,
NULL, 0, NULL, NULL, NULL, pcb);
BN_GENCB_free(pcb);
if (ret)
EVP_PKEY_assign_DSA(pkey, dsa);
else
DSA_free(dsa);
return ret;
}
static int pkey_dsa_keygen(EVP_PKEY_CTX *ctx, EVP_PKEY *pkey)
{
DSA *dsa = NULL;
if (ctx->pkey == NULL) {
DSAerr(DSA_F_PKEY_DSA_KEYGEN, DSA_R_NO_PARAMETERS_SET);
return 0;
}
dsa = DSA_new();
if (dsa == NULL)
return 0;
EVP_PKEY_assign_DSA(pkey, dsa);
/* Note: if error return, pkey is freed by parent routine */
if (!EVP_PKEY_copy_parameters(pkey, ctx->pkey))
return 0;
return DSA_generate_key(pkey->pkey.dsa);
}
const EVP_PKEY_METHOD dsa_pkey_meth = {
EVP_PKEY_DSA,
EVP_PKEY_FLAG_AUTOARGLEN,
pkey_dsa_init,
pkey_dsa_copy,
pkey_dsa_cleanup,
0,
pkey_dsa_paramgen,
0,
pkey_dsa_keygen,
0,
pkey_dsa_sign,
0,
pkey_dsa_verify,
0, 0,
0, 0, 0, 0,
0, 0,
0, 0,
0, 0,
pkey_dsa_ctrl,
pkey_dsa_ctrl_str
};