openssl/crypto/pkcs7/pk7_lib.c
Emilia Kasper 9104dc4255 PKCS#7: avoid NULL pointer dereferences with missing content
In PKCS#7, the ASN.1 content component is optional.
This typically applies to inner content (detached signatures),
however we must also handle unexpected missing outer content
correctly.

This patch only addresses functions reachable from parsing,
decryption and verification, and functions otherwise associated
with reading potentially untrusted data.

Correcting all low-level API calls requires further work.

CVE-2015-0289

Thanks to Michal Zalewski (Google) for reporting this issue.

Reviewed-by: Steve Henson <steve@openssl.org>
2015-03-19 13:00:11 +00:00

646 lines
18 KiB
C

/* crypto/pkcs7/pk7_lib.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/objects.h>
#include <openssl/x509.h>
#include "asn1_locl.h"
long PKCS7_ctrl(PKCS7 *p7, int cmd, long larg, char *parg)
{
int nid;
long ret;
nid = OBJ_obj2nid(p7->type);
switch (cmd) {
/* NOTE(emilia): does not support detached digested data. */
case PKCS7_OP_SET_DETACHED_SIGNATURE:
if (nid == NID_pkcs7_signed) {
ret = p7->detached = (int)larg;
if (ret && PKCS7_type_is_data(p7->d.sign->contents)) {
ASN1_OCTET_STRING *os;
os = p7->d.sign->contents->d.data;
ASN1_OCTET_STRING_free(os);
p7->d.sign->contents->d.data = NULL;
}
} else {
PKCS7err(PKCS7_F_PKCS7_CTRL,
PKCS7_R_OPERATION_NOT_SUPPORTED_ON_THIS_TYPE);
ret = 0;
}
break;
case PKCS7_OP_GET_DETACHED_SIGNATURE:
if (nid == NID_pkcs7_signed) {
if (!p7->d.sign || !p7->d.sign->contents->d.ptr)
ret = 1;
else
ret = 0;
p7->detached = ret;
} else {
PKCS7err(PKCS7_F_PKCS7_CTRL,
PKCS7_R_OPERATION_NOT_SUPPORTED_ON_THIS_TYPE);
ret = 0;
}
break;
default:
PKCS7err(PKCS7_F_PKCS7_CTRL, PKCS7_R_UNKNOWN_OPERATION);
ret = 0;
}
return (ret);
}
int PKCS7_content_new(PKCS7 *p7, int type)
{
PKCS7 *ret = NULL;
if ((ret = PKCS7_new()) == NULL)
goto err;
if (!PKCS7_set_type(ret, type))
goto err;
if (!PKCS7_set_content(p7, ret))
goto err;
return (1);
err:
if (ret != NULL)
PKCS7_free(ret);
return (0);
}
int PKCS7_set_content(PKCS7 *p7, PKCS7 *p7_data)
{
int i;
i = OBJ_obj2nid(p7->type);
switch (i) {
case NID_pkcs7_signed:
if (p7->d.sign->contents != NULL)
PKCS7_free(p7->d.sign->contents);
p7->d.sign->contents = p7_data;
break;
case NID_pkcs7_digest:
if (p7->d.digest->contents != NULL)
PKCS7_free(p7->d.digest->contents);
p7->d.digest->contents = p7_data;
break;
case NID_pkcs7_data:
case NID_pkcs7_enveloped:
case NID_pkcs7_signedAndEnveloped:
case NID_pkcs7_encrypted:
default:
PKCS7err(PKCS7_F_PKCS7_SET_CONTENT, PKCS7_R_UNSUPPORTED_CONTENT_TYPE);
goto err;
}
return (1);
err:
return (0);
}
int PKCS7_set_type(PKCS7 *p7, int type)
{
ASN1_OBJECT *obj;
/*
* PKCS7_content_free(p7);
*/
obj = OBJ_nid2obj(type); /* will not fail */
switch (type) {
case NID_pkcs7_signed:
p7->type = obj;
if ((p7->d.sign = PKCS7_SIGNED_new()) == NULL)
goto err;
if (!ASN1_INTEGER_set(p7->d.sign->version, 1)) {
PKCS7_SIGNED_free(p7->d.sign);
p7->d.sign = NULL;
goto err;
}
break;
case NID_pkcs7_data:
p7->type = obj;
if ((p7->d.data = M_ASN1_OCTET_STRING_new()) == NULL)
goto err;
break;
case NID_pkcs7_signedAndEnveloped:
p7->type = obj;
if ((p7->d.signed_and_enveloped = PKCS7_SIGN_ENVELOPE_new())
== NULL)
goto err;
ASN1_INTEGER_set(p7->d.signed_and_enveloped->version, 1);
if (!ASN1_INTEGER_set(p7->d.signed_and_enveloped->version, 1))
goto err;
p7->d.signed_and_enveloped->enc_data->content_type
= OBJ_nid2obj(NID_pkcs7_data);
break;
case NID_pkcs7_enveloped:
p7->type = obj;
if ((p7->d.enveloped = PKCS7_ENVELOPE_new())
== NULL)
goto err;
if (!ASN1_INTEGER_set(p7->d.enveloped->version, 0))
goto err;
p7->d.enveloped->enc_data->content_type = OBJ_nid2obj(NID_pkcs7_data);
break;
case NID_pkcs7_encrypted:
p7->type = obj;
if ((p7->d.encrypted = PKCS7_ENCRYPT_new())
== NULL)
goto err;
if (!ASN1_INTEGER_set(p7->d.encrypted->version, 0))
goto err;
p7->d.encrypted->enc_data->content_type = OBJ_nid2obj(NID_pkcs7_data);
break;
case NID_pkcs7_digest:
p7->type = obj;
if ((p7->d.digest = PKCS7_DIGEST_new())
== NULL)
goto err;
if (!ASN1_INTEGER_set(p7->d.digest->version, 0))
goto err;
break;
default:
PKCS7err(PKCS7_F_PKCS7_SET_TYPE, PKCS7_R_UNSUPPORTED_CONTENT_TYPE);
goto err;
}
return (1);
err:
return (0);
}
int PKCS7_set0_type_other(PKCS7 *p7, int type, ASN1_TYPE *other)
{
p7->type = OBJ_nid2obj(type);
p7->d.other = other;
return 1;
}
int PKCS7_add_signer(PKCS7 *p7, PKCS7_SIGNER_INFO *psi)
{
int i, j, nid;
X509_ALGOR *alg;
STACK_OF(PKCS7_SIGNER_INFO) *signer_sk;
STACK_OF(X509_ALGOR) *md_sk;
i = OBJ_obj2nid(p7->type);
switch (i) {
case NID_pkcs7_signed:
signer_sk = p7->d.sign->signer_info;
md_sk = p7->d.sign->md_algs;
break;
case NID_pkcs7_signedAndEnveloped:
signer_sk = p7->d.signed_and_enveloped->signer_info;
md_sk = p7->d.signed_and_enveloped->md_algs;
break;
default:
PKCS7err(PKCS7_F_PKCS7_ADD_SIGNER, PKCS7_R_WRONG_CONTENT_TYPE);
return (0);
}
nid = OBJ_obj2nid(psi->digest_alg->algorithm);
/* If the digest is not currently listed, add it */
j = 0;
for (i = 0; i < sk_X509_ALGOR_num(md_sk); i++) {
alg = sk_X509_ALGOR_value(md_sk, i);
if (OBJ_obj2nid(alg->algorithm) == nid) {
j = 1;
break;
}
}
if (!j) { /* we need to add another algorithm */
if (!(alg = X509_ALGOR_new())
|| !(alg->parameter = ASN1_TYPE_new())) {
X509_ALGOR_free(alg);
PKCS7err(PKCS7_F_PKCS7_ADD_SIGNER, ERR_R_MALLOC_FAILURE);
return (0);
}
alg->algorithm = OBJ_nid2obj(nid);
alg->parameter->type = V_ASN1_NULL;
if (!sk_X509_ALGOR_push(md_sk, alg)) {
X509_ALGOR_free(alg);
return 0;
}
}
if (!sk_PKCS7_SIGNER_INFO_push(signer_sk, psi))
return 0;
return (1);
}
int PKCS7_add_certificate(PKCS7 *p7, X509 *x509)
{
int i;
STACK_OF(X509) **sk;
i = OBJ_obj2nid(p7->type);
switch (i) {
case NID_pkcs7_signed:
sk = &(p7->d.sign->cert);
break;
case NID_pkcs7_signedAndEnveloped:
sk = &(p7->d.signed_and_enveloped->cert);
break;
default:
PKCS7err(PKCS7_F_PKCS7_ADD_CERTIFICATE, PKCS7_R_WRONG_CONTENT_TYPE);
return (0);
}
if (*sk == NULL)
*sk = sk_X509_new_null();
if (*sk == NULL) {
PKCS7err(PKCS7_F_PKCS7_ADD_CERTIFICATE, ERR_R_MALLOC_FAILURE);
return 0;
}
CRYPTO_add(&x509->references, 1, CRYPTO_LOCK_X509);
if (!sk_X509_push(*sk, x509)) {
X509_free(x509);
return 0;
}
return (1);
}
int PKCS7_add_crl(PKCS7 *p7, X509_CRL *crl)
{
int i;
STACK_OF(X509_CRL) **sk;
i = OBJ_obj2nid(p7->type);
switch (i) {
case NID_pkcs7_signed:
sk = &(p7->d.sign->crl);
break;
case NID_pkcs7_signedAndEnveloped:
sk = &(p7->d.signed_and_enveloped->crl);
break;
default:
PKCS7err(PKCS7_F_PKCS7_ADD_CRL, PKCS7_R_WRONG_CONTENT_TYPE);
return (0);
}
if (*sk == NULL)
*sk = sk_X509_CRL_new_null();
if (*sk == NULL) {
PKCS7err(PKCS7_F_PKCS7_ADD_CRL, ERR_R_MALLOC_FAILURE);
return 0;
}
CRYPTO_add(&crl->references, 1, CRYPTO_LOCK_X509_CRL);
if (!sk_X509_CRL_push(*sk, crl)) {
X509_CRL_free(crl);
return 0;
}
return (1);
}
int PKCS7_SIGNER_INFO_set(PKCS7_SIGNER_INFO *p7i, X509 *x509, EVP_PKEY *pkey,
const EVP_MD *dgst)
{
int ret;
/* We now need to add another PKCS7_SIGNER_INFO entry */
if (!ASN1_INTEGER_set(p7i->version, 1))
goto err;
if (!X509_NAME_set(&p7i->issuer_and_serial->issuer,
X509_get_issuer_name(x509)))
goto err;
/*
* because ASN1_INTEGER_set is used to set a 'long' we will do things the
* ugly way.
*/
M_ASN1_INTEGER_free(p7i->issuer_and_serial->serial);
if (!(p7i->issuer_and_serial->serial =
M_ASN1_INTEGER_dup(X509_get_serialNumber(x509))))
goto err;
/* lets keep the pkey around for a while */
CRYPTO_add(&pkey->references, 1, CRYPTO_LOCK_EVP_PKEY);
p7i->pkey = pkey;
/* Set the algorithms */
X509_ALGOR_set0(p7i->digest_alg, OBJ_nid2obj(EVP_MD_type(dgst)),
V_ASN1_NULL, NULL);
if (pkey->ameth && pkey->ameth->pkey_ctrl) {
ret = pkey->ameth->pkey_ctrl(pkey, ASN1_PKEY_CTRL_PKCS7_SIGN, 0, p7i);
if (ret > 0)
return 1;
if (ret != -2) {
PKCS7err(PKCS7_F_PKCS7_SIGNER_INFO_SET,
PKCS7_R_SIGNING_CTRL_FAILURE);
return 0;
}
}
PKCS7err(PKCS7_F_PKCS7_SIGNER_INFO_SET,
PKCS7_R_SIGNING_NOT_SUPPORTED_FOR_THIS_KEY_TYPE);
err:
return 0;
}
PKCS7_SIGNER_INFO *PKCS7_add_signature(PKCS7 *p7, X509 *x509, EVP_PKEY *pkey,
const EVP_MD *dgst)
{
PKCS7_SIGNER_INFO *si = NULL;
if (dgst == NULL) {
int def_nid;
if (EVP_PKEY_get_default_digest_nid(pkey, &def_nid) <= 0)
goto err;
dgst = EVP_get_digestbynid(def_nid);
if (dgst == NULL) {
PKCS7err(PKCS7_F_PKCS7_ADD_SIGNATURE, PKCS7_R_NO_DEFAULT_DIGEST);
goto err;
}
}
if ((si = PKCS7_SIGNER_INFO_new()) == NULL)
goto err;
if (!PKCS7_SIGNER_INFO_set(si, x509, pkey, dgst))
goto err;
if (!PKCS7_add_signer(p7, si))
goto err;
return (si);
err:
if (si)
PKCS7_SIGNER_INFO_free(si);
return (NULL);
}
int PKCS7_set_digest(PKCS7 *p7, const EVP_MD *md)
{
if (PKCS7_type_is_digest(p7)) {
if (!(p7->d.digest->md->parameter = ASN1_TYPE_new())) {
PKCS7err(PKCS7_F_PKCS7_SET_DIGEST, ERR_R_MALLOC_FAILURE);
return 0;
}
p7->d.digest->md->parameter->type = V_ASN1_NULL;
p7->d.digest->md->algorithm = OBJ_nid2obj(EVP_MD_nid(md));
return 1;
}
PKCS7err(PKCS7_F_PKCS7_SET_DIGEST, PKCS7_R_WRONG_CONTENT_TYPE);
return 1;
}
STACK_OF(PKCS7_SIGNER_INFO) *PKCS7_get_signer_info(PKCS7 *p7)
{
if (p7 == NULL || p7->d.ptr == NULL)
return NULL;
if (PKCS7_type_is_signed(p7)) {
return (p7->d.sign->signer_info);
} else if (PKCS7_type_is_signedAndEnveloped(p7)) {
return (p7->d.signed_and_enveloped->signer_info);
} else
return (NULL);
}
void PKCS7_SIGNER_INFO_get0_algs(PKCS7_SIGNER_INFO *si, EVP_PKEY **pk,
X509_ALGOR **pdig, X509_ALGOR **psig)
{
if (pk)
*pk = si->pkey;
if (pdig)
*pdig = si->digest_alg;
if (psig)
*psig = si->digest_enc_alg;
}
void PKCS7_RECIP_INFO_get0_alg(PKCS7_RECIP_INFO *ri, X509_ALGOR **penc)
{
if (penc)
*penc = ri->key_enc_algor;
}
PKCS7_RECIP_INFO *PKCS7_add_recipient(PKCS7 *p7, X509 *x509)
{
PKCS7_RECIP_INFO *ri;
if ((ri = PKCS7_RECIP_INFO_new()) == NULL)
goto err;
if (!PKCS7_RECIP_INFO_set(ri, x509))
goto err;
if (!PKCS7_add_recipient_info(p7, ri))
goto err;
return ri;
err:
if (ri)
PKCS7_RECIP_INFO_free(ri);
return NULL;
}
int PKCS7_add_recipient_info(PKCS7 *p7, PKCS7_RECIP_INFO *ri)
{
int i;
STACK_OF(PKCS7_RECIP_INFO) *sk;
i = OBJ_obj2nid(p7->type);
switch (i) {
case NID_pkcs7_signedAndEnveloped:
sk = p7->d.signed_and_enveloped->recipientinfo;
break;
case NID_pkcs7_enveloped:
sk = p7->d.enveloped->recipientinfo;
break;
default:
PKCS7err(PKCS7_F_PKCS7_ADD_RECIPIENT_INFO,
PKCS7_R_WRONG_CONTENT_TYPE);
return (0);
}
if (!sk_PKCS7_RECIP_INFO_push(sk, ri))
return 0;
return (1);
}
int PKCS7_RECIP_INFO_set(PKCS7_RECIP_INFO *p7i, X509 *x509)
{
int ret;
EVP_PKEY *pkey = NULL;
if (!ASN1_INTEGER_set(p7i->version, 0))
return 0;
if (!X509_NAME_set(&p7i->issuer_and_serial->issuer,
X509_get_issuer_name(x509)))
return 0;
M_ASN1_INTEGER_free(p7i->issuer_and_serial->serial);
if (!(p7i->issuer_and_serial->serial =
M_ASN1_INTEGER_dup(X509_get_serialNumber(x509))))
return 0;
pkey = X509_get_pubkey(x509);
if (!pkey || !pkey->ameth || !pkey->ameth->pkey_ctrl) {
PKCS7err(PKCS7_F_PKCS7_RECIP_INFO_SET,
PKCS7_R_ENCRYPTION_NOT_SUPPORTED_FOR_THIS_KEY_TYPE);
goto err;
}
ret = pkey->ameth->pkey_ctrl(pkey, ASN1_PKEY_CTRL_PKCS7_ENCRYPT, 0, p7i);
if (ret == -2) {
PKCS7err(PKCS7_F_PKCS7_RECIP_INFO_SET,
PKCS7_R_ENCRYPTION_NOT_SUPPORTED_FOR_THIS_KEY_TYPE);
goto err;
}
if (ret <= 0) {
PKCS7err(PKCS7_F_PKCS7_RECIP_INFO_SET,
PKCS7_R_ENCRYPTION_CTRL_FAILURE);
goto err;
}
EVP_PKEY_free(pkey);
CRYPTO_add(&x509->references, 1, CRYPTO_LOCK_X509);
p7i->cert = x509;
return 1;
err:
if (pkey)
EVP_PKEY_free(pkey);
return 0;
}
X509 *PKCS7_cert_from_signer_info(PKCS7 *p7, PKCS7_SIGNER_INFO *si)
{
if (PKCS7_type_is_signed(p7))
return (X509_find_by_issuer_and_serial(p7->d.sign->cert,
si->issuer_and_serial->issuer,
si->
issuer_and_serial->serial));
else
return (NULL);
}
int PKCS7_set_cipher(PKCS7 *p7, const EVP_CIPHER *cipher)
{
int i;
PKCS7_ENC_CONTENT *ec;
i = OBJ_obj2nid(p7->type);
switch (i) {
case NID_pkcs7_signedAndEnveloped:
ec = p7->d.signed_and_enveloped->enc_data;
break;
case NID_pkcs7_enveloped:
ec = p7->d.enveloped->enc_data;
break;
default:
PKCS7err(PKCS7_F_PKCS7_SET_CIPHER, PKCS7_R_WRONG_CONTENT_TYPE);
return (0);
}
/* Check cipher OID exists and has data in it */
i = EVP_CIPHER_type(cipher);
if (i == NID_undef) {
PKCS7err(PKCS7_F_PKCS7_SET_CIPHER,
PKCS7_R_CIPHER_HAS_NO_OBJECT_IDENTIFIER);
return (0);
}
ec->cipher = cipher;
return 1;
}
int PKCS7_stream(unsigned char ***boundary, PKCS7 *p7)
{
ASN1_OCTET_STRING *os = NULL;
switch (OBJ_obj2nid(p7->type)) {
case NID_pkcs7_data:
os = p7->d.data;
break;
case NID_pkcs7_signedAndEnveloped:
os = p7->d.signed_and_enveloped->enc_data->enc_data;
if (os == NULL) {
os = M_ASN1_OCTET_STRING_new();
p7->d.signed_and_enveloped->enc_data->enc_data = os;
}
break;
case NID_pkcs7_enveloped:
os = p7->d.enveloped->enc_data->enc_data;
if (os == NULL) {
os = M_ASN1_OCTET_STRING_new();
p7->d.enveloped->enc_data->enc_data = os;
}
break;
case NID_pkcs7_signed:
os = p7->d.sign->contents->d.data;
break;
default:
os = NULL;
break;
}
if (os == NULL)
return 0;
os->flags |= ASN1_STRING_FLAG_NDEF;
*boundary = &os->data;
return 1;
}