-/* crypto/dsa/dsa_sign.c */
-/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
- * All rights reserved.
+/*
+ * Copyright 1995-2020 The OpenSSL Project Authors. All Rights Reserved.
*
- * This package is an SSL implementation written
- * by Eric Young (eay@cryptsoft.com).
- * The implementation was written so as to conform with Netscapes SSL.
- *
- * This library is free for commercial and non-commercial use as long as
- * the following conditions are aheared to. The following conditions
- * apply to all code found in this distribution, be it the RC4, RSA,
- * lhash, DES, etc., code; not just the SSL code. The SSL documentation
- * included with this distribution is covered by the same copyright terms
- * except that the holder is Tim Hudson (tjh@cryptsoft.com).
- *
- * Copyright remains Eric Young's, and as such any Copyright notices in
- * the code are not to be removed.
- * If this package is used in a product, Eric Young should be given attribution
- * as the author of the parts of the library used.
- * This can be in the form of a textual message at program startup or
- * in documentation (online or textual) provided with the package.
- *
- * 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 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 acknowledgement:
- * "This product includes cryptographic software written by
- * Eric Young (eay@cryptsoft.com)"
- * The word 'cryptographic' can be left out if the rouines from the library
- * being used are not cryptographic related :-).
- * 4. If you include any Windows specific code (or a derivative thereof) from
- * the apps directory (application code) you must include an acknowledgement:
- * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
- *
- * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``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 AUTHOR 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.
- *
- * The licence and distribution terms for any publically available version or
- * derivative of this code cannot be changed. i.e. this code cannot simply be
- * copied and put under another distribution licence
- * [including the GNU Public Licence.]
+ * Licensed under the Apache License 2.0 (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
*/
-/* Original version from Steven Schoch <schoch@sheba.arc.nasa.gov> */
+/*
+ * DSA low level APIs are deprecated for public use, but still ok for
+ * internal use.
+ */
+#include "internal/deprecated.h"
+
+#include <openssl/bn.h>
+#include "internal/cryptlib.h"
+#include "dsa_local.h"
+#include "crypto/asn1_dsa.h"
+#include "crypto/dsa.h"
+
+DSA_SIG *DSA_do_sign(const unsigned char *dgst, int dlen, DSA *dsa)
+{
+ return dsa->meth->dsa_do_sign(dgst, dlen, dsa);
+}
+
+#ifndef OPENSSL_NO_DEPRECATED_3_0
+int DSA_sign_setup(DSA *dsa, BN_CTX *ctx_in, BIGNUM **kinvp, BIGNUM **rp)
+{
+ return dsa->meth->dsa_sign_setup(dsa, ctx_in, kinvp, rp);
+}
+#endif
-#include <stdio.h>
-#include "cryptlib.h"
-#include "bn.h"
-#include "dsa.h"
-#include "rand.h"
-#include "asn1.h"
+DSA_SIG *DSA_SIG_new(void)
+{
+ DSA_SIG *sig = OPENSSL_zalloc(sizeof(*sig));
+ if (sig == NULL)
+ DSAerr(DSA_F_DSA_SIG_NEW, ERR_R_MALLOC_FAILURE);
+ return sig;
+}
+
+void DSA_SIG_free(DSA_SIG *sig)
+{
+ if (sig == NULL)
+ return;
+ BN_clear_free(sig->r);
+ BN_clear_free(sig->s);
+ OPENSSL_free(sig);
+}
+
+DSA_SIG *d2i_DSA_SIG(DSA_SIG **psig, const unsigned char **ppin, long len)
+{
+ DSA_SIG *sig;
+
+ if (len < 0)
+ return NULL;
+ if (psig != NULL && *psig != NULL) {
+ sig = *psig;
+ } else {
+ sig = DSA_SIG_new();
+ if (sig == NULL)
+ return NULL;
+ }
+ if (sig->r == NULL)
+ sig->r = BN_new();
+ if (sig->s == NULL)
+ sig->s = BN_new();
+ if (ossl_decode_der_dsa_sig(sig->r, sig->s, ppin, (size_t)len) == 0) {
+ if (psig == NULL || *psig == NULL)
+ DSA_SIG_free(sig);
+ return NULL;
+ }
+ if (psig != NULL && *psig == NULL)
+ *psig = sig;
+ return sig;
+}
+
+int i2d_DSA_SIG(const DSA_SIG *sig, unsigned char **ppout)
+{
+ BUF_MEM *buf = NULL;
+ size_t encoded_len;
+ WPACKET pkt;
+
+ if (ppout == NULL) {
+ if (!WPACKET_init_null(&pkt, 0))
+ return -1;
+ } else if (*ppout == NULL) {
+ if ((buf = BUF_MEM_new()) == NULL
+ || !WPACKET_init_len(&pkt, buf, 0)) {
+ BUF_MEM_free(buf);
+ return -1;
+ }
+ } else {
+ if (!WPACKET_init_static_len(&pkt, *ppout, SIZE_MAX, 0))
+ return -1;
+ }
+
+ if (!encode_der_dsa_sig(&pkt, sig->r, sig->s)
+ || !WPACKET_get_total_written(&pkt, &encoded_len)
+ || !WPACKET_finish(&pkt)) {
+ BUF_MEM_free(buf);
+ WPACKET_cleanup(&pkt);
+ return -1;
+ }
+
+ if (ppout != NULL) {
+ if (*ppout == NULL) {
+ *ppout = (unsigned char *)buf->data;
+ buf->data = NULL;
+ BUF_MEM_free(buf);
+ } else {
+ *ppout += encoded_len;
+ }
+ }
+
+ return (int)encoded_len;
+}
+
+int DSA_size(const DSA *dsa)
+{
+ int ret;
+ DSA_SIG sig;
+
+ sig.r = sig.s = dsa->params.q;
+ ret = i2d_DSA_SIG(&sig, NULL);
+
+ if (ret < 0)
+ ret = 0;
+ return ret;
+}
+
+void DSA_SIG_get0(const DSA_SIG *sig, const BIGNUM **pr, const BIGNUM **ps)
+{
+ if (pr != NULL)
+ *pr = sig->r;
+ if (ps != NULL)
+ *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;
+}
+
+int dsa_sign_int(int type, const unsigned char *dgst,
+ int dlen, unsigned char *sig, unsigned int *siglen, DSA *dsa)
+{
+ DSA_SIG *s;
+
+ /* legacy case uses the method table */
+ if (dsa->libctx == NULL || dsa->meth != DSA_get_default_method())
+ s = DSA_do_sign(dgst, dlen, dsa);
+ else
+ s = dsa_do_sign_int(dgst, dlen, dsa);
+ if (s == NULL) {
+ *siglen = 0;
+ return 0;
+ }
+ *siglen = i2d_DSA_SIG(s, &sig);
+ DSA_SIG_free(s);
+ return 1;
+}
+
+int DSA_sign(int type, const unsigned char *dgst, int dlen,
+ unsigned char *sig, unsigned int *siglen, DSA *dsa)
+{
+ return dsa_sign_int(type, dgst, dlen, sig, siglen, dsa);
+}
/* data has already been hashed (probably with SHA or SHA-1). */
-/* DSAerr(DSA_F_DSA_SIGN,DSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE); */
-
-int DSA_sign(type,dgst,dlen,sig,siglen,dsa)
-int type;
-unsigned char *dgst;
-int dlen;
-unsigned char *sig; /* out */
-unsigned int *siglen; /* out */
-DSA *dsa;
- {
- BIGNUM *kinv=NULL,*r=NULL;
- BIGNUM m;
- BIGNUM xr,s;
- BN_CTX *ctx=NULL;
- unsigned char *p;
- int i,len=0,ret=0,reason=ERR_R_BN_LIB;
- ASN1_INTEGER rbs,sbs;
- MS_STATIC unsigned char rbuf[50]; /* assuming r is 20 bytes +extra */
- MS_STATIC unsigned char sbuf[50]; /* assuming s is 20 bytes +extra */
-
- BN_init(&m);
- BN_init(&xr);
- BN_init(&s);
-
- i=BN_num_bytes(dsa->q); /* should be 20 */
- if ((dlen > i) || (dlen > 50))
- {
- reason=DSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE;
- goto err;
- }
-
- ctx=BN_CTX_new();
- if (ctx == NULL) goto err;
-
- if ((dsa->kinv == NULL) || (dsa->r == NULL))
- {
- if (!DSA_sign_setup(dsa,ctx,&kinv,&r)) goto err;
- }
- else
- {
- kinv=dsa->kinv;
- dsa->kinv=NULL;
- r=dsa->r;
- dsa->r=NULL;
- }
-
- if (BN_bin2bn(dgst,dlen,&m) == NULL) goto err;
-
- /* Compute s = inv(k) (m + xr) mod q */
- if (!BN_mod_mul(&xr,dsa->priv_key,r,dsa->q,ctx)) goto err;/* s = xr */
- if (!BN_add(&s, &xr, &m)) goto err; /* s = m + xr */
- if (BN_cmp(&s,dsa->q) > 0)
- BN_sub(&s,&s,dsa->q);
- if (!BN_mod_mul(&s,&s,kinv,dsa->q,ctx)) goto err;
-
- /*
- * Now create a ASN.1 sequence of the integers R and S.
- */
- rbs.data=rbuf;
- sbs.data=sbuf;
- rbs.type = V_ASN1_INTEGER;
- sbs.type = V_ASN1_INTEGER;
- rbs.length=BN_bn2bin(r,rbs.data);
- sbs.length=BN_bn2bin(&s,sbs.data);
-
- len =i2d_ASN1_INTEGER(&rbs,NULL);
- len+=i2d_ASN1_INTEGER(&sbs,NULL);
-
- p=sig;
- ASN1_put_object(&p,1,len,V_ASN1_SEQUENCE,V_ASN1_UNIVERSAL);
- i2d_ASN1_INTEGER(&rbs,&p);
- i2d_ASN1_INTEGER(&sbs,&p);
- *siglen=(p-sig);
- ret=1;
-err:
- if (!ret) DSAerr(DSA_F_DSA_SIGN,reason);
-
-#if 1 /* do the right thing :-) */
- if (kinv != NULL) BN_clear_free(kinv);
- if (r != NULL) BN_clear_free(r);
-#endif
- if (ctx != NULL) BN_CTX_free(ctx);
- BN_clear_free(&m);
- BN_clear_free(&xr);
- BN_clear_free(&s);
- return(ret);
- }
-
-int DSA_sign_setup(dsa,ctx_in,kinvp,rp)
-DSA *dsa;
-BN_CTX *ctx_in;
-BIGNUM **kinvp;
-BIGNUM **rp;
- {
- BN_CTX *ctx;
- BIGNUM k,*kinv=NULL,*r=NULL;
- int ret=0;
-
- if (ctx_in == NULL)
- {
- if ((ctx=BN_CTX_new()) == NULL) goto err;
- }
- else
- ctx=ctx_in;
-
- BN_init(&k);
- if ((r=BN_new()) == NULL) goto err;
- kinv=NULL;
-
- /* Get random k */
- for (;;)
- {
- if (!BN_rand(&k, BN_num_bits(dsa->q), 1, 0)) goto err;
- if (BN_cmp(&k,dsa->q) >= 0)
- BN_sub(&k,&k,dsa->q);
- if (!BN_is_zero(&k)) break;
- }
-
- if ((dsa->method_mont_p == NULL) && (dsa->flags & DSA_FLAG_CACHE_MONT_P))
- {
- if ((dsa->method_mont_p=(char *)BN_MONT_CTX_new()) != NULL)
- if (!BN_MONT_CTX_set((BN_MONT_CTX *)dsa->method_mont_p,
- dsa->p,ctx)) goto err;
- }
-
- /* Compute r = (g^k mod p) mod q */
- if (!BN_mod_exp_mont(r,dsa->g,&k,dsa->p,ctx,
- (BN_MONT_CTX *)dsa->method_mont_p)) goto err;
- if (!BN_mod(r,r,dsa->q,ctx)) goto err;
-
- /* Compute part of 's = inv(k) (m + xr) mod q' */
- if ((kinv=BN_mod_inverse(NULL,&k,dsa->q,ctx)) == NULL) goto err;
-
- if (*kinvp != NULL) BN_clear_free(*kinvp);
- *kinvp=kinv;
- kinv=NULL;
- if (*rp != NULL) BN_clear_free(*rp);
- *rp=r;
- ret=1;
-err:
- if (!ret)
- {
- DSAerr(DSA_F_DSA_SIGN_SETUP,ERR_R_BN_LIB);
- if (kinv != NULL) BN_clear_free(kinv);
- if (r != NULL) BN_clear_free(r);
- }
- if (ctx_in == NULL) BN_CTX_free(ctx);
- if (kinv != NULL) BN_clear_free(kinv);
- BN_clear_free(&k);
- return(ret);
- }
+/*-
+ * 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;
+}
projects / thirdparty / openssl.git / blobdiff