openssl/crypto/pkcs7/pk7_smime.c

550 lines
16 KiB
C

/*
* Copyright 1999-2020 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
*/
/* Simple PKCS#7 processing functions */
#include <stdio.h>
#include "internal/cryptlib.h"
#include <openssl/x509.h>
#include <openssl/x509v3.h>
#define BUFFERSIZE 4096
static int pkcs7_copy_existing_digest(PKCS7 *p7, PKCS7_SIGNER_INFO *si);
PKCS7 *PKCS7_sign(X509 *signcert, EVP_PKEY *pkey, STACK_OF(X509) *certs,
BIO *data, int flags)
{
PKCS7 *p7;
int i;
if ((p7 = PKCS7_new()) == NULL) {
PKCS7err(PKCS7_F_PKCS7_SIGN, ERR_R_MALLOC_FAILURE);
return NULL;
}
if (!PKCS7_set_type(p7, NID_pkcs7_signed))
goto err;
if (!PKCS7_content_new(p7, NID_pkcs7_data))
goto err;
if (pkey && !PKCS7_sign_add_signer(p7, signcert, pkey, NULL, flags)) {
PKCS7err(PKCS7_F_PKCS7_SIGN, PKCS7_R_PKCS7_ADD_SIGNER_ERROR);
goto err;
}
if (!(flags & PKCS7_NOCERTS)) {
for (i = 0; i < sk_X509_num(certs); i++) {
if (!PKCS7_add_certificate(p7, sk_X509_value(certs, i)))
goto err;
}
}
if (flags & PKCS7_DETACHED)
PKCS7_set_detached(p7, 1);
if (flags & (PKCS7_STREAM | PKCS7_PARTIAL))
return p7;
if (PKCS7_final(p7, data, flags))
return p7;
err:
PKCS7_free(p7);
return NULL;
}
int PKCS7_final(PKCS7 *p7, BIO *data, int flags)
{
BIO *p7bio;
int ret = 0;
if ((p7bio = PKCS7_dataInit(p7, NULL)) == NULL) {
PKCS7err(PKCS7_F_PKCS7_FINAL, ERR_R_MALLOC_FAILURE);
return 0;
}
SMIME_crlf_copy(data, p7bio, flags);
(void)BIO_flush(p7bio);
if (!PKCS7_dataFinal(p7, p7bio)) {
PKCS7err(PKCS7_F_PKCS7_FINAL, PKCS7_R_PKCS7_DATASIGN);
goto err;
}
ret = 1;
err:
BIO_free_all(p7bio);
return ret;
}
/* Check to see if a cipher exists and if so add S/MIME capabilities */
static int add_cipher_smcap(STACK_OF(X509_ALGOR) *sk, int nid, int arg)
{
if (EVP_get_cipherbynid(nid))
return PKCS7_simple_smimecap(sk, nid, arg);
return 1;
}
static int add_digest_smcap(STACK_OF(X509_ALGOR) *sk, int nid, int arg)
{
if (EVP_get_digestbynid(nid))
return PKCS7_simple_smimecap(sk, nid, arg);
return 1;
}
PKCS7_SIGNER_INFO *PKCS7_sign_add_signer(PKCS7 *p7, X509 *signcert,
EVP_PKEY *pkey, const EVP_MD *md,
int flags)
{
PKCS7_SIGNER_INFO *si = NULL;
STACK_OF(X509_ALGOR) *smcap = NULL;
if (!X509_check_private_key(signcert, pkey)) {
PKCS7err(PKCS7_F_PKCS7_SIGN_ADD_SIGNER,
PKCS7_R_PRIVATE_KEY_DOES_NOT_MATCH_CERTIFICATE);
return NULL;
}
if ((si = PKCS7_add_signature(p7, signcert, pkey, md)) == NULL) {
PKCS7err(PKCS7_F_PKCS7_SIGN_ADD_SIGNER,
PKCS7_R_PKCS7_ADD_SIGNATURE_ERROR);
return NULL;
}
if (!(flags & PKCS7_NOCERTS)) {
if (!PKCS7_add_certificate(p7, signcert))
goto err;
}
if (!(flags & PKCS7_NOATTR)) {
if (!PKCS7_add_attrib_content_type(si, NULL))
goto err;
/* Add SMIMECapabilities */
if (!(flags & PKCS7_NOSMIMECAP)) {
if ((smcap = sk_X509_ALGOR_new_null()) == NULL) {
PKCS7err(PKCS7_F_PKCS7_SIGN_ADD_SIGNER, ERR_R_MALLOC_FAILURE);
goto err;
}
if (!add_cipher_smcap(smcap, NID_aes_256_cbc, -1)
|| !add_digest_smcap(smcap, NID_id_GostR3411_2012_256, -1)
|| !add_digest_smcap(smcap, NID_id_GostR3411_2012_512, -1)
|| !add_digest_smcap(smcap, NID_id_GostR3411_94, -1)
|| !add_cipher_smcap(smcap, NID_id_Gost28147_89, -1)
|| !add_cipher_smcap(smcap, NID_aes_192_cbc, -1)
|| !add_cipher_smcap(smcap, NID_aes_128_cbc, -1)
|| !add_cipher_smcap(smcap, NID_des_ede3_cbc, -1)
|| !add_cipher_smcap(smcap, NID_rc2_cbc, 128)
|| !add_cipher_smcap(smcap, NID_rc2_cbc, 64)
|| !add_cipher_smcap(smcap, NID_des_cbc, -1)
|| !add_cipher_smcap(smcap, NID_rc2_cbc, 40)
|| !PKCS7_add_attrib_smimecap(si, smcap))
goto err;
sk_X509_ALGOR_pop_free(smcap, X509_ALGOR_free);
smcap = NULL;
}
if (flags & PKCS7_REUSE_DIGEST) {
if (!pkcs7_copy_existing_digest(p7, si))
goto err;
if (!(flags & PKCS7_PARTIAL) && !PKCS7_SIGNER_INFO_sign(si))
goto err;
}
}
return si;
err:
sk_X509_ALGOR_pop_free(smcap, X509_ALGOR_free);
return NULL;
}
/*
* Search for a digest matching SignerInfo digest type and if found copy
* across.
*/
static int pkcs7_copy_existing_digest(PKCS7 *p7, PKCS7_SIGNER_INFO *si)
{
int i;
STACK_OF(PKCS7_SIGNER_INFO) *sinfos;
PKCS7_SIGNER_INFO *sitmp;
ASN1_OCTET_STRING *osdig = NULL;
sinfos = PKCS7_get_signer_info(p7);
for (i = 0; i < sk_PKCS7_SIGNER_INFO_num(sinfos); i++) {
sitmp = sk_PKCS7_SIGNER_INFO_value(sinfos, i);
if (si == sitmp)
break;
if (sk_X509_ATTRIBUTE_num(sitmp->auth_attr) <= 0)
continue;
if (!OBJ_cmp(si->digest_alg->algorithm, sitmp->digest_alg->algorithm)) {
osdig = PKCS7_digest_from_attributes(sitmp->auth_attr);
break;
}
}
if (osdig)
return PKCS7_add1_attrib_digest(si, osdig->data, osdig->length);
PKCS7err(PKCS7_F_PKCS7_COPY_EXISTING_DIGEST,
PKCS7_R_NO_MATCHING_DIGEST_TYPE_FOUND);
return 0;
}
int PKCS7_verify(PKCS7 *p7, STACK_OF(X509) *certs, X509_STORE *store,
BIO *indata, BIO *out, int flags)
{
STACK_OF(X509) *signers;
X509 *signer;
STACK_OF(PKCS7_SIGNER_INFO) *sinfos;
PKCS7_SIGNER_INFO *si;
X509_STORE_CTX *cert_ctx = NULL;
char *buf = NULL;
int i, j = 0, k, ret = 0;
BIO *p7bio = NULL;
BIO *tmpin = NULL, *tmpout = NULL;
if (!p7) {
PKCS7err(PKCS7_F_PKCS7_VERIFY, PKCS7_R_INVALID_NULL_POINTER);
return 0;
}
if (!PKCS7_type_is_signed(p7)) {
PKCS7err(PKCS7_F_PKCS7_VERIFY, PKCS7_R_WRONG_CONTENT_TYPE);
return 0;
}
/* Check for no data and no content: no data to verify signature */
if (PKCS7_get_detached(p7) && !indata) {
PKCS7err(PKCS7_F_PKCS7_VERIFY, PKCS7_R_NO_CONTENT);
return 0;
}
if (flags & PKCS7_NO_DUAL_CONTENT) {
/*
* This was originally "#if 0" because we thought that only old broken
* Netscape did this. It turns out that Authenticode uses this kind
* of "extended" PKCS7 format, and things like UEFI secure boot and
* tools like osslsigncode need it. In Authenticode the verification
* process is different, but the existing PKCs7 verification works.
*/
if (!PKCS7_get_detached(p7) && indata) {
PKCS7err(PKCS7_F_PKCS7_VERIFY, PKCS7_R_CONTENT_AND_DATA_PRESENT);
return 0;
}
}
sinfos = PKCS7_get_signer_info(p7);
if (!sinfos || !sk_PKCS7_SIGNER_INFO_num(sinfos)) {
PKCS7err(PKCS7_F_PKCS7_VERIFY, PKCS7_R_NO_SIGNATURES_ON_DATA);
return 0;
}
signers = PKCS7_get0_signers(p7, certs, flags);
if (!signers)
return 0;
/* Now verify the certificates */
cert_ctx = X509_STORE_CTX_new();
if (cert_ctx == NULL)
goto err;
if (!(flags & PKCS7_NOVERIFY))
for (k = 0; k < sk_X509_num(signers); k++) {
signer = sk_X509_value(signers, k);
if (!(flags & PKCS7_NOCHAIN)) {
if (!X509_STORE_CTX_init(cert_ctx, store, signer,
p7->d.sign->cert)) {
PKCS7err(PKCS7_F_PKCS7_VERIFY, ERR_R_X509_LIB);
goto err;
}
X509_STORE_CTX_set_default(cert_ctx, "smime_sign");
} else if (!X509_STORE_CTX_init(cert_ctx, store, signer, NULL)) {
PKCS7err(PKCS7_F_PKCS7_VERIFY, ERR_R_X509_LIB);
goto err;
}
if (!(flags & PKCS7_NOCRL))
X509_STORE_CTX_set0_crls(cert_ctx, p7->d.sign->crl);
i = X509_verify_cert(cert_ctx);
if (i <= 0)
j = X509_STORE_CTX_get_error(cert_ctx);
X509_STORE_CTX_cleanup(cert_ctx);
if (i <= 0) {
PKCS7err(PKCS7_F_PKCS7_VERIFY,
PKCS7_R_CERTIFICATE_VERIFY_ERROR);
ERR_add_error_data(2, "Verify error:",
X509_verify_cert_error_string(j));
goto err;
}
/* Check for revocation status here */
}
/*
* Performance optimization: if the content is a memory BIO then store
* its contents in a temporary read only memory BIO. This avoids
* potentially large numbers of slow copies of data which will occur when
* reading from a read write memory BIO when signatures are calculated.
*/
if (indata && (BIO_method_type(indata) == BIO_TYPE_MEM)) {
char *ptr;
long len;
len = BIO_get_mem_data(indata, &ptr);
tmpin = (len == 0) ? indata : BIO_new_mem_buf(ptr, len);
if (tmpin == NULL) {
PKCS7err(PKCS7_F_PKCS7_VERIFY, ERR_R_MALLOC_FAILURE);
goto err;
}
} else
tmpin = indata;
if ((p7bio = PKCS7_dataInit(p7, tmpin)) == NULL)
goto err;
if (flags & PKCS7_TEXT) {
if ((tmpout = BIO_new(BIO_s_mem())) == NULL) {
PKCS7err(PKCS7_F_PKCS7_VERIFY, ERR_R_MALLOC_FAILURE);
goto err;
}
BIO_set_mem_eof_return(tmpout, 0);
} else
tmpout = out;
/* We now have to 'read' from p7bio to calculate digests etc. */
if ((buf = OPENSSL_malloc(BUFFERSIZE)) == NULL) {
PKCS7err(PKCS7_F_PKCS7_VERIFY, ERR_R_MALLOC_FAILURE);
goto err;
}
for (;;) {
i = BIO_read(p7bio, buf, BUFFERSIZE);
if (i <= 0)
break;
if (tmpout)
BIO_write(tmpout, buf, i);
}
if (flags & PKCS7_TEXT) {
if (!SMIME_text(tmpout, out)) {
PKCS7err(PKCS7_F_PKCS7_VERIFY, PKCS7_R_SMIME_TEXT_ERROR);
BIO_free(tmpout);
goto err;
}
BIO_free(tmpout);
}
/* Now Verify All Signatures */
if (!(flags & PKCS7_NOSIGS))
for (i = 0; i < sk_PKCS7_SIGNER_INFO_num(sinfos); i++) {
si = sk_PKCS7_SIGNER_INFO_value(sinfos, i);
signer = sk_X509_value(signers, i);
j = PKCS7_signatureVerify(p7bio, p7, si, signer);
if (j <= 0) {
PKCS7err(PKCS7_F_PKCS7_VERIFY, PKCS7_R_SIGNATURE_FAILURE);
goto err;
}
}
ret = 1;
err:
X509_STORE_CTX_free(cert_ctx);
OPENSSL_free(buf);
if (tmpin == indata) {
if (indata)
BIO_pop(p7bio);
}
BIO_free_all(p7bio);
sk_X509_free(signers);
return ret;
}
STACK_OF(X509) *PKCS7_get0_signers(PKCS7 *p7, STACK_OF(X509) *certs,
int flags)
{
STACK_OF(X509) *signers;
STACK_OF(PKCS7_SIGNER_INFO) *sinfos;
PKCS7_SIGNER_INFO *si;
PKCS7_ISSUER_AND_SERIAL *ias;
X509 *signer;
int i;
if (!p7) {
PKCS7err(PKCS7_F_PKCS7_GET0_SIGNERS, PKCS7_R_INVALID_NULL_POINTER);
return NULL;
}
if (!PKCS7_type_is_signed(p7)) {
PKCS7err(PKCS7_F_PKCS7_GET0_SIGNERS, PKCS7_R_WRONG_CONTENT_TYPE);
return NULL;
}
/* Collect all the signers together */
sinfos = PKCS7_get_signer_info(p7);
if (sk_PKCS7_SIGNER_INFO_num(sinfos) <= 0) {
PKCS7err(PKCS7_F_PKCS7_GET0_SIGNERS, PKCS7_R_NO_SIGNERS);
return 0;
}
if ((signers = sk_X509_new_null()) == NULL) {
PKCS7err(PKCS7_F_PKCS7_GET0_SIGNERS, ERR_R_MALLOC_FAILURE);
return NULL;
}
for (i = 0; i < sk_PKCS7_SIGNER_INFO_num(sinfos); i++) {
si = sk_PKCS7_SIGNER_INFO_value(sinfos, i);
ias = si->issuer_and_serial;
signer = NULL;
/* If any certificates passed they take priority */
if (certs)
signer = X509_find_by_issuer_and_serial(certs,
ias->issuer, ias->serial);
if (!signer && !(flags & PKCS7_NOINTERN)
&& p7->d.sign->cert)
signer =
X509_find_by_issuer_and_serial(p7->d.sign->cert,
ias->issuer, ias->serial);
if (!signer) {
PKCS7err(PKCS7_F_PKCS7_GET0_SIGNERS,
PKCS7_R_SIGNER_CERTIFICATE_NOT_FOUND);
sk_X509_free(signers);
return 0;
}
if (!sk_X509_push(signers, signer)) {
sk_X509_free(signers);
return NULL;
}
}
return signers;
}
/* Build a complete PKCS#7 enveloped data */
PKCS7 *PKCS7_encrypt(STACK_OF(X509) *certs, BIO *in, const EVP_CIPHER *cipher,
int flags)
{
PKCS7 *p7;
BIO *p7bio = NULL;
int i;
X509 *x509;
if ((p7 = PKCS7_new()) == NULL) {
PKCS7err(PKCS7_F_PKCS7_ENCRYPT, ERR_R_MALLOC_FAILURE);
return NULL;
}
if (!PKCS7_set_type(p7, NID_pkcs7_enveloped))
goto err;
if (!PKCS7_set_cipher(p7, cipher)) {
PKCS7err(PKCS7_F_PKCS7_ENCRYPT, PKCS7_R_ERROR_SETTING_CIPHER);
goto err;
}
for (i = 0; i < sk_X509_num(certs); i++) {
x509 = sk_X509_value(certs, i);
if (!PKCS7_add_recipient(p7, x509)) {
PKCS7err(PKCS7_F_PKCS7_ENCRYPT, PKCS7_R_ERROR_ADDING_RECIPIENT);
goto err;
}
}
if (flags & PKCS7_STREAM)
return p7;
if (PKCS7_final(p7, in, flags))
return p7;
err:
BIO_free_all(p7bio);
PKCS7_free(p7);
return NULL;
}
int PKCS7_decrypt(PKCS7 *p7, EVP_PKEY *pkey, X509 *cert, BIO *data, int flags)
{
BIO *tmpmem;
int ret = 0, i;
char *buf = NULL;
if (!p7) {
PKCS7err(PKCS7_F_PKCS7_DECRYPT, PKCS7_R_INVALID_NULL_POINTER);
return 0;
}
if (!PKCS7_type_is_enveloped(p7)) {
PKCS7err(PKCS7_F_PKCS7_DECRYPT, PKCS7_R_WRONG_CONTENT_TYPE);
return 0;
}
if (cert && !X509_check_private_key(cert, pkey)) {
PKCS7err(PKCS7_F_PKCS7_DECRYPT,
PKCS7_R_PRIVATE_KEY_DOES_NOT_MATCH_CERTIFICATE);
return 0;
}
if ((tmpmem = PKCS7_dataDecode(p7, pkey, NULL, cert)) == NULL) {
PKCS7err(PKCS7_F_PKCS7_DECRYPT, PKCS7_R_DECRYPT_ERROR);
return 0;
}
if (flags & PKCS7_TEXT) {
BIO *tmpbuf, *bread;
/* Encrypt BIOs can't do BIO_gets() so add a buffer BIO */
if ((tmpbuf = BIO_new(BIO_f_buffer())) == NULL) {
PKCS7err(PKCS7_F_PKCS7_DECRYPT, ERR_R_MALLOC_FAILURE);
BIO_free_all(tmpmem);
return 0;
}
if ((bread = BIO_push(tmpbuf, tmpmem)) == NULL) {
PKCS7err(PKCS7_F_PKCS7_DECRYPT, ERR_R_MALLOC_FAILURE);
BIO_free_all(tmpbuf);
BIO_free_all(tmpmem);
return 0;
}
ret = SMIME_text(bread, data);
if (ret > 0 && BIO_method_type(tmpmem) == BIO_TYPE_CIPHER) {
if (!BIO_get_cipher_status(tmpmem))
ret = 0;
}
BIO_free_all(bread);
return ret;
}
if ((buf = OPENSSL_malloc(BUFFERSIZE)) == NULL) {
PKCS7err(PKCS7_F_PKCS7_DECRYPT, ERR_R_MALLOC_FAILURE);
goto err;
}
for (;;) {
i = BIO_read(tmpmem, buf, BUFFERSIZE);
if (i <= 0) {
ret = 1;
if (BIO_method_type(tmpmem) == BIO_TYPE_CIPHER) {
if (!BIO_get_cipher_status(tmpmem))
ret = 0;
}
break;
}
if (BIO_write(data, buf, i) != i) {
break;
}
}
err:
OPENSSL_free(buf);
BIO_free_all(tmpmem);
return ret;
}