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pk7_doit.c
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pk7_doit.c
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/* $OpenBSD: pk7_doit.c,v 1.56 2024/02/18 15:45:42 tb Exp $ */
/* 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 <stdlib.h>
#include <string.h>
#include <openssl/err.h>
#include <openssl/objects.h>
#include <openssl/x509.h>
#include <openssl/x509v3.h>
#include "evp_local.h"
#include "x509_local.h"
static int
PKCS7_type_is_other(PKCS7* p7)
{
int isOther = 1;
int nid = OBJ_obj2nid(p7->type);
switch (nid ) {
case NID_pkcs7_data:
case NID_pkcs7_signed:
case NID_pkcs7_enveloped:
case NID_pkcs7_signedAndEnveloped:
case NID_pkcs7_digest:
case NID_pkcs7_encrypted:
isOther = 0;
break;
default:
isOther = 1;
}
return isOther;
}
ASN1_OCTET_STRING *
PKCS7_get_octet_string(PKCS7 *p7)
{
if (PKCS7_type_is_data(p7))
return p7->d.data;
if (PKCS7_type_is_other(p7) && p7->d.other &&
(p7->d.other->type == V_ASN1_OCTET_STRING))
return p7->d.other->value.octet_string;
return NULL;
}
static int
PKCS7_bio_add_digest(BIO **pbio, X509_ALGOR *alg)
{
BIO *btmp;
const EVP_MD *md;
if ((btmp = BIO_new(BIO_f_md())) == NULL) {
PKCS7error(ERR_R_BIO_LIB);
goto err;
}
md = EVP_get_digestbyobj(alg->algorithm);
if (md == NULL) {
PKCS7error(PKCS7_R_UNKNOWN_DIGEST_TYPE);
goto err;
}
if (BIO_set_md(btmp, md) <= 0) {
PKCS7error(ERR_R_BIO_LIB);
goto err;
}
if (*pbio == NULL)
*pbio = btmp;
else if (!BIO_push(*pbio, btmp)) {
PKCS7error(ERR_R_BIO_LIB);
goto err;
}
btmp = NULL;
return 1;
err:
BIO_free(btmp);
return 0;
}
static int
pkcs7_encode_rinfo(PKCS7_RECIP_INFO *ri, unsigned char *key, int keylen)
{
EVP_PKEY_CTX *pctx = NULL;
EVP_PKEY *pkey = NULL;
unsigned char *ek = NULL;
int ret = 0;
size_t eklen;
pkey = X509_get_pubkey(ri->cert);
if (!pkey)
return 0;
pctx = EVP_PKEY_CTX_new(pkey, NULL);
if (!pctx)
return 0;
if (EVP_PKEY_encrypt_init(pctx) <= 0)
goto err;
if (EVP_PKEY_CTX_ctrl(pctx, -1, EVP_PKEY_OP_ENCRYPT,
EVP_PKEY_CTRL_PKCS7_ENCRYPT, 0, ri) <= 0) {
PKCS7error(PKCS7_R_CTRL_ERROR);
goto err;
}
if (EVP_PKEY_encrypt(pctx, NULL, &eklen, key, keylen) <= 0)
goto err;
ek = malloc(eklen);
if (ek == NULL) {
PKCS7error(ERR_R_MALLOC_FAILURE);
goto err;
}
if (EVP_PKEY_encrypt(pctx, ek, &eklen, key, keylen) <= 0)
goto err;
ASN1_STRING_set0(ri->enc_key, ek, eklen);
ek = NULL;
ret = 1;
err:
EVP_PKEY_free(pkey);
EVP_PKEY_CTX_free(pctx);
free(ek);
return ret;
}
static int
pkcs7_decrypt_rinfo(unsigned char **pek, int *peklen, PKCS7_RECIP_INFO *ri,
EVP_PKEY *pkey, size_t fixlen)
{
EVP_PKEY_CTX *pctx = NULL;
unsigned char *ek = NULL;
size_t eklen;
int ret = -1;
pctx = EVP_PKEY_CTX_new(pkey, NULL);
if (!pctx)
return -1;
if (EVP_PKEY_decrypt_init(pctx) <= 0)
goto err;
if (EVP_PKEY_CTX_ctrl(pctx, -1, EVP_PKEY_OP_DECRYPT,
EVP_PKEY_CTRL_PKCS7_DECRYPT, 0, ri) <= 0) {
PKCS7error(PKCS7_R_CTRL_ERROR);
goto err;
}
if (EVP_PKEY_decrypt(pctx, NULL, &eklen,
ri->enc_key->data, ri->enc_key->length) <= 0)
goto err;
ek = malloc(eklen);
if (ek == NULL) {
PKCS7error(ERR_R_MALLOC_FAILURE);
goto err;
}
if (EVP_PKEY_decrypt(pctx, ek, &eklen, ri->enc_key->data,
ri->enc_key->length) <= 0 || eklen == 0 ||
(fixlen != 0 && eklen != fixlen)) {
ret = 0;
PKCS7error(ERR_R_EVP_LIB);
goto err;
}
ret = 1;
freezero(*pek, *peklen);
*pek = ek;
*peklen = eklen;
err:
EVP_PKEY_CTX_free(pctx);
if (!ret && ek)
free(ek);
return ret;
}
BIO *
PKCS7_dataInit(PKCS7 *p7, BIO *bio)
{
int i;
BIO *out = NULL, *btmp = NULL;
X509_ALGOR *xa = NULL;
const EVP_CIPHER *evp_cipher = NULL;
STACK_OF(X509_ALGOR) *md_sk = NULL;
STACK_OF(PKCS7_RECIP_INFO) *rsk = NULL;
X509_ALGOR *xalg = NULL;
PKCS7_RECIP_INFO *ri = NULL;
ASN1_OCTET_STRING *os = NULL;
if (p7 == NULL) {
PKCS7error(PKCS7_R_INVALID_NULL_POINTER);
return NULL;
}
/*
* The content field in the PKCS7 ContentInfo is optional,
* but that really only applies to inner content (precisely,
* detached signatures).
*
* When reading content, missing outer content is therefore
* treated as an error.
*
* When creating content, PKCS7_content_new() must be called
* before calling this method, so a NULL p7->d is always
* an error.
*/
if (p7->d.ptr == NULL) {
PKCS7error(PKCS7_R_NO_CONTENT);
return NULL;
}
i = OBJ_obj2nid(p7->type);
p7->state = PKCS7_S_HEADER;
switch (i) {
case NID_pkcs7_signed:
md_sk = p7->d.sign->md_algs;
os = PKCS7_get_octet_string(p7->d.sign->contents);
break;
case NID_pkcs7_signedAndEnveloped:
rsk = p7->d.signed_and_enveloped->recipientinfo;
md_sk = p7->d.signed_and_enveloped->md_algs;
xalg = p7->d.signed_and_enveloped->enc_data->algorithm;
evp_cipher = p7->d.signed_and_enveloped->enc_data->cipher;
if (evp_cipher == NULL) {
PKCS7error(PKCS7_R_CIPHER_NOT_INITIALIZED);
goto err;
}
break;
case NID_pkcs7_enveloped:
rsk = p7->d.enveloped->recipientinfo;
xalg = p7->d.enveloped->enc_data->algorithm;
evp_cipher = p7->d.enveloped->enc_data->cipher;
if (evp_cipher == NULL) {
PKCS7error(PKCS7_R_CIPHER_NOT_INITIALIZED);
goto err;
}
break;
case NID_pkcs7_digest:
xa = p7->d.digest->md;
os = PKCS7_get_octet_string(p7->d.digest->contents);
break;
case NID_pkcs7_data:
break;
default:
PKCS7error(PKCS7_R_UNSUPPORTED_CONTENT_TYPE);
goto err;
}
for (i = 0; i < sk_X509_ALGOR_num(md_sk); i++)
if (!PKCS7_bio_add_digest(&out, sk_X509_ALGOR_value(md_sk, i)))
goto err;
if (xa && !PKCS7_bio_add_digest(&out, xa))
goto err;
if (evp_cipher != NULL) {
unsigned char key[EVP_MAX_KEY_LENGTH];
unsigned char iv[EVP_MAX_IV_LENGTH];
int keylen, ivlen;
EVP_CIPHER_CTX *ctx;
if ((btmp = BIO_new(BIO_f_cipher())) == NULL) {
PKCS7error(ERR_R_BIO_LIB);
goto err;
}
BIO_get_cipher_ctx(btmp, &ctx);
keylen = EVP_CIPHER_key_length(evp_cipher);
ivlen = EVP_CIPHER_iv_length(evp_cipher);
xalg->algorithm = OBJ_nid2obj(EVP_CIPHER_type(evp_cipher));
if (ivlen > 0)
arc4random_buf(iv, ivlen);
if (EVP_CipherInit_ex(ctx, evp_cipher, NULL, NULL,
NULL, 1) <= 0)
goto err;
if (EVP_CIPHER_CTX_rand_key(ctx, key) <= 0)
goto err;
if (EVP_CipherInit_ex(ctx, NULL, NULL, key, iv, 1) <= 0)
goto err;
if (ivlen > 0) {
if (xalg->parameter == NULL) {
xalg->parameter = ASN1_TYPE_new();
if (xalg->parameter == NULL)
goto err;
}
if (EVP_CIPHER_param_to_asn1(ctx, xalg->parameter) < 0)
goto err;
}
/* Lets do the pub key stuff :-) */
for (i = 0; i < sk_PKCS7_RECIP_INFO_num(rsk); i++) {
ri = sk_PKCS7_RECIP_INFO_value(rsk, i);
if (pkcs7_encode_rinfo(ri, key, keylen) <= 0)
goto err;
}
explicit_bzero(key, keylen);
if (out == NULL)
out = btmp;
else
BIO_push(out, btmp);
btmp = NULL;
}
if (bio == NULL) {
if (PKCS7_is_detached(p7))
bio = BIO_new(BIO_s_null());
else if (os && os->length > 0)
bio = BIO_new_mem_buf(os->data, os->length);
if (bio == NULL) {
bio = BIO_new(BIO_s_mem());
if (bio == NULL)
goto err;
BIO_set_mem_eof_return(bio, 0);
}
}
if (out)
BIO_push(out, bio);
else
out = bio;
bio = NULL;
if (0) {
err:
if (out != NULL)
BIO_free_all(out);
if (btmp != NULL)
BIO_free_all(btmp);
out = NULL;
}
return out;
}
LCRYPTO_ALIAS(PKCS7_dataInit);
static int
pkcs7_cmp_ri(PKCS7_RECIP_INFO *ri, X509 *pcert)
{
int ret;
ret = X509_NAME_cmp(ri->issuer_and_serial->issuer,
pcert->cert_info->issuer);
if (ret)
return ret;
return ASN1_INTEGER_cmp(pcert->cert_info->serialNumber,
ri->issuer_and_serial->serial);
}
/* int */
BIO *
PKCS7_dataDecode(PKCS7 *p7, EVP_PKEY *pkey, BIO *in_bio, X509 *pcert)
{
int i, j;
BIO *out = NULL, *btmp = NULL, *etmp = NULL, *bio = NULL;
X509_ALGOR *xa;
ASN1_OCTET_STRING *data_body = NULL;
const EVP_MD *evp_md;
const EVP_CIPHER *evp_cipher = NULL;
EVP_CIPHER_CTX *evp_ctx = NULL;
X509_ALGOR *enc_alg = NULL;
STACK_OF(X509_ALGOR) *md_sk = NULL;
STACK_OF(PKCS7_RECIP_INFO) *rsk = NULL;
PKCS7_RECIP_INFO *ri = NULL;
unsigned char *ek = NULL, *tkey = NULL;
int eklen = 0, tkeylen = 0;
if (p7 == NULL) {
PKCS7error(PKCS7_R_INVALID_NULL_POINTER);
return NULL;
}
if (p7->d.ptr == NULL) {
PKCS7error(PKCS7_R_NO_CONTENT);
return NULL;
}
i = OBJ_obj2nid(p7->type);
p7->state = PKCS7_S_HEADER;
switch (i) {
case NID_pkcs7_signed:
data_body = PKCS7_get_octet_string(p7->d.sign->contents);
md_sk = p7->d.sign->md_algs;
break;
case NID_pkcs7_signedAndEnveloped:
rsk = p7->d.signed_and_enveloped->recipientinfo;
md_sk = p7->d.signed_and_enveloped->md_algs;
data_body = p7->d.signed_and_enveloped->enc_data->enc_data;
enc_alg = p7->d.signed_and_enveloped->enc_data->algorithm;
evp_cipher = EVP_get_cipherbyobj(enc_alg->algorithm);
if (evp_cipher == NULL) {
PKCS7error(PKCS7_R_UNSUPPORTED_CIPHER_TYPE);
goto err;
}
break;
case NID_pkcs7_enveloped:
rsk = p7->d.enveloped->recipientinfo;
enc_alg = p7->d.enveloped->enc_data->algorithm;
data_body = p7->d.enveloped->enc_data->enc_data;
evp_cipher = EVP_get_cipherbyobj(enc_alg->algorithm);
if (evp_cipher == NULL) {
PKCS7error(PKCS7_R_UNSUPPORTED_CIPHER_TYPE);
goto err;
}
break;
default:
PKCS7error(PKCS7_R_UNSUPPORTED_CONTENT_TYPE);
goto err;
}
/* We will be checking the signature */
if (md_sk != NULL) {
for (i = 0; i < sk_X509_ALGOR_num(md_sk); i++) {
xa = sk_X509_ALGOR_value(md_sk, i);
if ((btmp = BIO_new(BIO_f_md())) == NULL) {
PKCS7error(ERR_R_BIO_LIB);
goto err;
}
j = OBJ_obj2nid(xa->algorithm);
evp_md = EVP_get_digestbynid(j);
if (evp_md == NULL) {
PKCS7error(PKCS7_R_UNKNOWN_DIGEST_TYPE);
goto err;
}
if (BIO_set_md(btmp, evp_md) <= 0) {
PKCS7error(ERR_R_BIO_LIB);
goto err;
}
if (out == NULL)
out = btmp;
else
BIO_push(out, btmp);
btmp = NULL;
}
}
if (evp_cipher != NULL) {
if ((etmp = BIO_new(BIO_f_cipher())) == NULL) {
PKCS7error(ERR_R_BIO_LIB);
goto err;
}
/* It was encrypted, we need to decrypt the secret key
* with the private key */
/* Find the recipientInfo which matches the passed certificate
* (if any)
*/
if (pcert) {
for (i = 0; i < sk_PKCS7_RECIP_INFO_num(rsk); i++) {
ri = sk_PKCS7_RECIP_INFO_value(rsk, i);
if (!pkcs7_cmp_ri(ri, pcert))
break;
ri = NULL;
}
if (ri == NULL) {
PKCS7error(PKCS7_R_NO_RECIPIENT_MATCHES_CERTIFICATE);
goto err;
}
}
/* If we haven't got a certificate try each ri in turn */
if (pcert == NULL) {
/* Always attempt to decrypt all rinfo even
* after success as a defence against MMA timing
* attacks.
*/
for (i = 0; i < sk_PKCS7_RECIP_INFO_num(rsk); i++) {
ri = sk_PKCS7_RECIP_INFO_value(rsk, i);
if (pkcs7_decrypt_rinfo(&ek, &eklen, ri, pkey,
EVP_CIPHER_key_length(evp_cipher)) < 0)
goto err;
ERR_clear_error();
}
} else {
/* Only exit on fatal errors, not decrypt failure */
if (pkcs7_decrypt_rinfo(&ek, &eklen, ri, pkey, 0) < 0)
goto err;
ERR_clear_error();
}
evp_ctx = NULL;
BIO_get_cipher_ctx(etmp, &evp_ctx);
if (EVP_CipherInit_ex(evp_ctx, evp_cipher, NULL, NULL,
NULL, 0) <= 0)
goto err;
if (EVP_CIPHER_asn1_to_param(evp_ctx, enc_alg->parameter) < 0)
goto err;
/* Generate random key as MMA defence */
tkeylen = EVP_CIPHER_CTX_key_length(evp_ctx);
tkey = malloc(tkeylen);
if (!tkey)
goto err;
if (EVP_CIPHER_CTX_rand_key(evp_ctx, tkey) <= 0)
goto err;
if (ek == NULL) {
ek = tkey;
eklen = tkeylen;
tkey = NULL;
}
if (eklen != EVP_CIPHER_CTX_key_length(evp_ctx)) {
/* Some S/MIME clients don't use the same key
* and effective key length. The key length is
* determined by the size of the decrypted RSA key.
*/
if (!EVP_CIPHER_CTX_set_key_length(evp_ctx, eklen)) {
/* Use random key as MMA defence */
freezero(ek, eklen);
ek = tkey;
eklen = tkeylen;
tkey = NULL;
}
}
/* Clear errors so we don't leak information useful in MMA */
ERR_clear_error();
if (EVP_CipherInit_ex(evp_ctx, NULL, NULL, ek, NULL, 0) <= 0)
goto err;
freezero(ek, eklen);
ek = NULL;
freezero(tkey, tkeylen);
tkey = NULL;
if (out == NULL)
out = etmp;
else
BIO_push(out, etmp);
etmp = NULL;
}
if (PKCS7_is_detached(p7) || (in_bio != NULL)) {
bio = in_bio;
} else {
if (data_body != NULL && data_body->length > 0)
bio = BIO_new_mem_buf(data_body->data, data_body->length);
else {
bio = BIO_new(BIO_s_mem());
BIO_set_mem_eof_return(bio, 0);
}
if (bio == NULL)
goto err;
}
BIO_push(out, bio);
if (0) {
err:
freezero(ek, eklen);
freezero(tkey, tkeylen);
if (out != NULL)
BIO_free_all(out);
if (btmp != NULL)
BIO_free_all(btmp);
if (etmp != NULL)
BIO_free_all(etmp);
out = NULL;
}
return out;
}
LCRYPTO_ALIAS(PKCS7_dataDecode);
static BIO *
PKCS7_find_digest(EVP_MD_CTX **pmd, BIO *bio, int nid)
{
for (;;) {
bio = BIO_find_type(bio, BIO_TYPE_MD);
if (bio == NULL) {
PKCS7error(PKCS7_R_UNABLE_TO_FIND_MESSAGE_DIGEST);
return NULL;
}
BIO_get_md_ctx(bio, pmd);
if (*pmd == NULL) {
PKCS7error(ERR_R_INTERNAL_ERROR);
return NULL;
}
if (EVP_MD_CTX_type(*pmd) == nid)
return bio;
bio = BIO_next(bio);
}
return NULL;
}
static int
do_pkcs7_signed_attrib(PKCS7_SIGNER_INFO *si, EVP_MD_CTX *mctx)
{
unsigned char md_data[EVP_MAX_MD_SIZE];
unsigned int md_len;
/* Add signing time if not already present */
if (!PKCS7_get_signed_attribute(si, NID_pkcs9_signingTime)) {
if (!PKCS7_add0_attrib_signing_time(si, NULL)) {
PKCS7error(ERR_R_MALLOC_FAILURE);
return 0;
}
}
/* Add digest */
if (!EVP_DigestFinal_ex(mctx, md_data, &md_len)) {
PKCS7error(ERR_R_EVP_LIB);
return 0;
}
if (!PKCS7_add1_attrib_digest(si, md_data, md_len)) {
PKCS7error(ERR_R_MALLOC_FAILURE);
return 0;
}
/* Now sign the attributes */
if (!PKCS7_SIGNER_INFO_sign(si))
return 0;
return 1;
}
int
PKCS7_dataFinal(PKCS7 *p7, BIO *bio)
{
int ret = 0;
int i, j;
BIO *btmp;
PKCS7_SIGNER_INFO *si;
EVP_MD_CTX *mdc, ctx_tmp;
STACK_OF(X509_ATTRIBUTE) *sk;
STACK_OF(PKCS7_SIGNER_INFO) *si_sk = NULL;
ASN1_OCTET_STRING *os = NULL;
if (p7 == NULL) {
PKCS7error(PKCS7_R_INVALID_NULL_POINTER);
return 0;
}
if (p7->d.ptr == NULL) {
PKCS7error(PKCS7_R_NO_CONTENT);
return 0;
}
EVP_MD_CTX_legacy_clear(&ctx_tmp);
i = OBJ_obj2nid(p7->type);
p7->state = PKCS7_S_HEADER;
switch (i) {
case NID_pkcs7_data:
os = p7->d.data;
break;
case NID_pkcs7_signedAndEnveloped:
/* XXX */
si_sk = p7->d.signed_and_enveloped->signer_info;
os = p7->d.signed_and_enveloped->enc_data->enc_data;
if (!os) {
os = ASN1_OCTET_STRING_new();
if (!os) {
PKCS7error(ERR_R_MALLOC_FAILURE);
goto err;
}
p7->d.signed_and_enveloped->enc_data->enc_data = os;
}
break;
case NID_pkcs7_enveloped:
/* XXX */
os = p7->d.enveloped->enc_data->enc_data;
if (!os) {
os = ASN1_OCTET_STRING_new();
if (!os) {
PKCS7error(ERR_R_MALLOC_FAILURE);
goto err;
}
p7->d.enveloped->enc_data->enc_data = os;
}
break;
case NID_pkcs7_signed:
si_sk = p7->d.sign->signer_info;
os = PKCS7_get_octet_string(p7->d.sign->contents);
if (!PKCS7_is_detached(p7) && os == NULL) {
PKCS7error(PKCS7_R_DECODE_ERROR);
goto err;
}
/* If detached data then the content is excluded */
if (PKCS7_type_is_data(p7->d.sign->contents) && p7->detached) {
ASN1_OCTET_STRING_free(os);
os = NULL;
p7->d.sign->contents->d.data = NULL;
}
break;
case NID_pkcs7_digest:
os = PKCS7_get_octet_string(p7->d.digest->contents);
if (os == NULL) {
PKCS7error(PKCS7_R_DECODE_ERROR);
goto err;
}
/* If detached data then the content is excluded */
if (PKCS7_type_is_data(p7->d.digest->contents) &&
p7->detached) {
ASN1_OCTET_STRING_free(os);
os = NULL;
p7->d.digest->contents->d.data = NULL;
}
break;
default:
PKCS7error(PKCS7_R_UNSUPPORTED_CONTENT_TYPE);
goto err;
}
if (si_sk != NULL) {
for (i = 0; i < sk_PKCS7_SIGNER_INFO_num(si_sk); i++) {
si = sk_PKCS7_SIGNER_INFO_value(si_sk, i);
if (si->pkey == NULL)
continue;
j = OBJ_obj2nid(si->digest_alg->algorithm);
if ((btmp = PKCS7_find_digest(&mdc, bio, j)) == NULL)
goto err;
/* We now have the EVP_MD_CTX, lets do the
* signing. */
if (!EVP_MD_CTX_copy_ex(&ctx_tmp, mdc))
goto err;
sk = si->auth_attr;
/* If there are attributes, we add the digest
* attribute and only sign the attributes */
if (sk_X509_ATTRIBUTE_num(sk) > 0) {
if (!do_pkcs7_signed_attrib(si, &ctx_tmp))
goto err;
} else {
unsigned char *abuf = NULL;
unsigned int abuflen;
abuflen = EVP_PKEY_size(si->pkey);
abuf = malloc(abuflen);
if (!abuf)
goto err;
if (!EVP_SignFinal(&ctx_tmp, abuf, &abuflen,
si->pkey)) {
PKCS7error(ERR_R_EVP_LIB);
goto err;
}
ASN1_STRING_set0(si->enc_digest, abuf, abuflen);
}
}
} else if (i == NID_pkcs7_digest) {
unsigned char md_data[EVP_MAX_MD_SIZE];
unsigned int md_len;
if (!PKCS7_find_digest(&mdc, bio,
OBJ_obj2nid(p7->d.digest->md->algorithm)))
goto err;
if (!EVP_DigestFinal_ex(mdc, md_data, &md_len))
goto err;
if (ASN1_STRING_set(p7->d.digest->digest, md_data,
md_len) == 0)
goto err;
}
if (!PKCS7_is_detached(p7)) {
/*
* NOTE: only reach os == NULL here because detached
* digested data support is broken?
*/
if (os == NULL)
goto err;
if (!(os->flags & ASN1_STRING_FLAG_NDEF)) {
char *cont;
long contlen;
btmp = BIO_find_type(bio, BIO_TYPE_MEM);
if (btmp == NULL) {
PKCS7error(PKCS7_R_UNABLE_TO_FIND_MEM_BIO);
goto err;
}
contlen = BIO_get_mem_data(btmp, &cont);
/*
* Mark the BIO read only then we can use its copy
* of the data instead of making an extra copy.
*/
BIO_set_flags(btmp, BIO_FLAGS_MEM_RDONLY);
BIO_set_mem_eof_return(btmp, 0);
ASN1_STRING_set0(os, (unsigned char *)cont, contlen);
}
}
ret = 1;
err:
EVP_MD_CTX_cleanup(&ctx_tmp);
return ret;
}
LCRYPTO_ALIAS(PKCS7_dataFinal);
int
PKCS7_SIGNER_INFO_sign(PKCS7_SIGNER_INFO *si)
{
EVP_MD_CTX mctx;
EVP_PKEY_CTX *pctx;
unsigned char *abuf = NULL;
int alen;
size_t siglen;
const EVP_MD *md = NULL;
md = EVP_get_digestbyobj(si->digest_alg->algorithm);
if (md == NULL)
return 0;
EVP_MD_CTX_legacy_clear(&mctx);
if (EVP_DigestSignInit(&mctx, &pctx, md, NULL, si->pkey) <= 0)
goto err;
if (EVP_PKEY_CTX_ctrl(pctx, -1, EVP_PKEY_OP_SIGN,
EVP_PKEY_CTRL_PKCS7_SIGN, 0, si) <= 0) {
PKCS7error(PKCS7_R_CTRL_ERROR);
goto err;
}
alen = ASN1_item_i2d((ASN1_VALUE *)si->auth_attr, &abuf,
&PKCS7_ATTR_SIGN_it);
if (!abuf)
goto err;
if (EVP_DigestSignUpdate(&mctx, abuf, alen) <= 0)
goto err;
free(abuf);
abuf = NULL;
if (EVP_DigestSignFinal(&mctx, NULL, &siglen) <= 0)
goto err;
abuf = malloc(siglen);
if (!abuf)
goto err;
if (EVP_DigestSignFinal(&mctx, abuf, &siglen) <= 0)
goto err;
if (EVP_PKEY_CTX_ctrl(pctx, -1, EVP_PKEY_OP_SIGN,
EVP_PKEY_CTRL_PKCS7_SIGN, 1, si) <= 0) {
PKCS7error(PKCS7_R_CTRL_ERROR);
goto err;
}
EVP_MD_CTX_cleanup(&mctx);
ASN1_STRING_set0(si->enc_digest, abuf, siglen);
return 1;
err:
free(abuf);
EVP_MD_CTX_cleanup(&mctx);
return 0;
}
LCRYPTO_ALIAS(PKCS7_SIGNER_INFO_sign);
int
PKCS7_dataVerify(X509_STORE *cert_store, X509_STORE_CTX *ctx, BIO *bio,
PKCS7 *p7, PKCS7_SIGNER_INFO *si)
{
PKCS7_ISSUER_AND_SERIAL *ias;
int ret = 0, i;
STACK_OF(X509) *cert;
X509 *x509;
if (p7 == NULL) {
PKCS7error(PKCS7_R_INVALID_NULL_POINTER);
return 0;
}
if (p7->d.ptr == NULL) {
PKCS7error(PKCS7_R_NO_CONTENT);
return 0;
}
if (PKCS7_type_is_signed(p7)) {
cert = p7->d.sign->cert;
} else if (PKCS7_type_is_signedAndEnveloped(p7)) {
cert = p7->d.signed_and_enveloped->cert;
} else {
PKCS7error(PKCS7_R_WRONG_PKCS7_TYPE);
goto err;
}
/* XXXX */
ias = si->issuer_and_serial;
x509 = X509_find_by_issuer_and_serial(cert, ias->issuer, ias->serial);
/* were we able to find the cert in passed to us */
if (x509 == NULL) {
PKCS7error(PKCS7_R_UNABLE_TO_FIND_CERTIFICATE);
goto err;
}
/* Lets verify */
if (!X509_STORE_CTX_init(ctx, cert_store, x509, cert)) {
PKCS7error(ERR_R_X509_LIB);
goto err;
}
if (X509_STORE_CTX_set_purpose(ctx, X509_PURPOSE_SMIME_SIGN) == 0) {
X509_STORE_CTX_cleanup(ctx);
goto err;
}
i = X509_verify_cert(ctx);
if (i <= 0) {
PKCS7error(ERR_R_X509_LIB);
X509_STORE_CTX_cleanup(ctx);
goto err;
}
X509_STORE_CTX_cleanup(ctx);
return PKCS7_signatureVerify(bio, p7, si, x509);
err:
return ret;
}
LCRYPTO_ALIAS(PKCS7_dataVerify);
int
PKCS7_signatureVerify(BIO *bio, PKCS7 *p7, PKCS7_SIGNER_INFO *si, X509 *x509)
{
ASN1_OCTET_STRING *os;
EVP_MD_CTX mdc_tmp, *mdc;
int ret = 0, i;
int md_type;
STACK_OF(X509_ATTRIBUTE) *sk;
BIO *btmp;
EVP_PKEY *pkey;
EVP_MD_CTX_legacy_clear(&mdc_tmp);