openssl/crypto/evp/p_sign.c
Gunnar Kudrjavets 4c9b0a0314 Initialize potentially uninitialized local variables
Compiling OpenSSL code with MSVC and /W4 results in a number of warnings.
One category of warnings is particularly interesting - C4701 (potentially
uninitialized local variable 'name' used). This warning pretty much means
that there's a code path which results in uninitialized variables being used
or returned. Depending on compiler, its options, OS, values in registers
and/or stack, the results can be nondeterministic. Cases like this are very
hard to debug so it's rational to fix these issues.

This patch contains a set of trivial fixes for all the C4701 warnings (just
initializing variables to 0 or NULL or appropriate error code) to make sure
that deterministic values will be returned from all the execution paths.

RT#3835

Signed-off-by: Matt Caswell <matt@openssl.org>

Matt's note: All of these appear to be bogus warnings, i.e. there isn't
actually a code path where an unitialised variable could be used - its just
that the compiler hasn't been able to figure that out from the logic. So
this commit is just about silencing spurious warnings.

Reviewed-by: Rich Salz <rsalz@openssl.org>
2015-05-06 13:06:46 +01:00

128 lines
5 KiB
C

/* crypto/evp/p_sign.c */
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
* 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.]
*/
#include <stdio.h>
#include "cryptlib.h"
#include <openssl/evp.h>
#include <openssl/objects.h>
#include <openssl/x509.h>
int EVP_SignFinal(EVP_MD_CTX *ctx, unsigned char *sigret,
unsigned int *siglen, EVP_PKEY *pkey)
{
unsigned char m[EVP_MAX_MD_SIZE];
unsigned int m_len = 0;
int i = 0, ok = 0, v = 0;
EVP_PKEY_CTX *pkctx = NULL;
*siglen = 0;
if (ctx->flags & EVP_MD_CTX_FLAG_FINALISE) {
if (!EVP_DigestFinal_ex(ctx, m, &m_len))
goto err;
} else {
int rv = 0;
EVP_MD_CTX tmp_ctx;
EVP_MD_CTX_init(&tmp_ctx);
rv = EVP_MD_CTX_copy_ex(&tmp_ctx, ctx);
if (rv)
rv = EVP_DigestFinal_ex(&tmp_ctx, m, &m_len);
EVP_MD_CTX_cleanup(&tmp_ctx);
if (!rv)
return 0;
}
if (ctx->digest->flags & EVP_MD_FLAG_PKEY_METHOD_SIGNATURE) {
size_t sltmp = (size_t)EVP_PKEY_size(pkey);
i = 0;
pkctx = EVP_PKEY_CTX_new(pkey, NULL);
if (!pkctx)
goto err;
if (EVP_PKEY_sign_init(pkctx) <= 0)
goto err;
if (EVP_PKEY_CTX_set_signature_md(pkctx, ctx->digest) <= 0)
goto err;
if (EVP_PKEY_sign(pkctx, sigret, &sltmp, m, m_len) <= 0)
goto err;
*siglen = sltmp;
i = 1;
err:
EVP_PKEY_CTX_free(pkctx);
return i;
}
for (i = 0; i < 4; i++) {
v = ctx->digest->required_pkey_type[i];
if (v == 0)
break;
if (pkey->type == v) {
ok = 1;
break;
}
}
if (!ok) {
EVPerr(EVP_F_EVP_SIGNFINAL, EVP_R_WRONG_PUBLIC_KEY_TYPE);
return (0);
}
if (ctx->digest->sign == NULL) {
EVPerr(EVP_F_EVP_SIGNFINAL, EVP_R_NO_SIGN_FUNCTION_CONFIGURED);
return (0);
}
return ctx->digest->sign(ctx->digest->type, m, m_len, sigret, siglen,
pkey->pkey.ptr);
}