Plan 9 from Bell Labs’s /usr/web/sources/contrib/fgb/root/sys/src/ape/lib/openssl/crypto/pkcs7/pk7_doit.c

Copyright © 2021 Plan 9 Foundation.
Distributed under the MIT License.
Download the Plan 9 distribution.


/* crypto/pkcs7/pk7_doit.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/rand.h>
#include <openssl/objects.h>
#include <openssl/x509.h>
#include <openssl/x509v3.h>
#include <openssl/err.h>

static int add_attribute(STACK_OF(X509_ATTRIBUTE) **sk, int nid, int atrtype,
			 void *value);
static ASN1_TYPE *get_attribute(STACK_OF(X509_ATTRIBUTE) *sk, int nid);

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;

	}

static 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)
		{
		PKCS7err(PKCS7_F_PKCS7_BIO_ADD_DIGEST,ERR_R_BIO_LIB);
		goto err;
		}

	md=EVP_get_digestbyobj(alg->algorithm);
	if (md == NULL)
		{
		PKCS7err(PKCS7_F_PKCS7_BIO_ADD_DIGEST,PKCS7_R_UNKNOWN_DIGEST_TYPE);
		goto err;
		}

	BIO_set_md(btmp,md);
	if (*pbio == NULL)
		*pbio=btmp;
	else if (!BIO_push(*pbio,btmp))
		{
		PKCS7err(PKCS7_F_PKCS7_BIO_ADD_DIGEST,ERR_R_BIO_LIB);
		goto err;
		}
	btmp=NULL;

	return 1;

	err:
	if (btmp)
		BIO_free(btmp);
	return 0;

	}

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;
	EVP_PKEY *pkey;
	ASN1_OCTET_STRING *os=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)
			{
			PKCS7err(PKCS7_F_PKCS7_DATAINIT,
						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)
			{
			PKCS7err(PKCS7_F_PKCS7_DATAINIT,
						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;
	default:
		PKCS7err(PKCS7_F_PKCS7_DATAINIT,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;
		int jj,max;
		unsigned char *tmp;
		EVP_CIPHER_CTX *ctx;

		if ((btmp=BIO_new(BIO_f_cipher())) == NULL)
			{
			PKCS7err(PKCS7_F_PKCS7_DATAINIT,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)
			if (RAND_pseudo_bytes(iv,ivlen) <= 0)
				goto err;
		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 :-) */
		max=0;
		for (i=0; i<sk_PKCS7_RECIP_INFO_num(rsk); i++)
			{
			ri=sk_PKCS7_RECIP_INFO_value(rsk,i);
			if (ri->cert == NULL)
				{
				PKCS7err(PKCS7_F_PKCS7_DATAINIT,PKCS7_R_MISSING_CERIPEND_INFO);
				goto err;
				}
			if ((pkey=X509_get_pubkey(ri->cert)) == NULL)
				goto err;
			jj=EVP_PKEY_size(pkey);
			EVP_PKEY_free(pkey);
			if (max < jj) max=jj;
			}
		if ((tmp=(unsigned char *)OPENSSL_malloc(max)) == NULL)
			{
			PKCS7err(PKCS7_F_PKCS7_DATAINIT,ERR_R_MALLOC_FAILURE);
			goto err;
			}
		for (i=0; i<sk_PKCS7_RECIP_INFO_num(rsk); i++)
			{
			ri=sk_PKCS7_RECIP_INFO_value(rsk,i);
			if ((pkey=X509_get_pubkey(ri->cert)) == NULL)
				goto err;
			jj=EVP_PKEY_encrypt(tmp,key,keylen,pkey);
			EVP_PKEY_free(pkey);
			if (jj <= 0)
				{
				PKCS7err(PKCS7_F_PKCS7_DATAINIT,ERR_R_EVP_LIB);
				OPENSSL_free(tmp);
				goto err;
				}
			if (!M_ASN1_OCTET_STRING_set(ri->enc_key,tmp,jj))
				{
				PKCS7err(PKCS7_F_PKCS7_DATAINIT,
					ERR_R_MALLOC_FAILURE);
				OPENSSL_free(tmp);
				goto err;
				}
			}
		OPENSSL_free(tmp);
		OPENSSL_cleanse(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);
			}
		}
	BIO_push(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);
	}

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 M_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;
	unsigned char *tmp=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;
	X509_ALGOR *xalg=NULL;
	PKCS7_RECIP_INFO *ri=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)
			{
			PKCS7err(PKCS7_F_PKCS7_DATADECODE,PKCS7_R_UNSUPPORTED_CIPHER_TYPE);
			goto err;
			}
		xalg=p7->d.signed_and_enveloped->enc_data->algorithm;
		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)
			{
			PKCS7err(PKCS7_F_PKCS7_DATADECODE,PKCS7_R_UNSUPPORTED_CIPHER_TYPE);
			goto err;
			}
		xalg=p7->d.enveloped->enc_data->algorithm;
		break;
	default:
		PKCS7err(PKCS7_F_PKCS7_DATADECODE,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)
				{
				PKCS7err(PKCS7_F_PKCS7_DATADECODE,ERR_R_BIO_LIB);
				goto err;
				}

			j=OBJ_obj2nid(xa->algorithm);
			evp_md=EVP_get_digestbynid(j);
			if (evp_md == NULL)
				{
				PKCS7err(PKCS7_F_PKCS7_DATADECODE,PKCS7_R_UNKNOWN_DIGEST_TYPE);
				goto err;
				}

			BIO_set_md(btmp,evp_md);
			if (out == NULL)
				out=btmp;
			else
				BIO_push(out,btmp);
			btmp=NULL;
			}
		}

	if (evp_cipher != NULL)
		{
#if 0
		unsigned char key[EVP_MAX_KEY_LENGTH];
		unsigned char iv[EVP_MAX_IV_LENGTH];
		unsigned char *p;
		int keylen,ivlen;
		int max;
		X509_OBJECT ret;
#endif
		int jj;

		if ((etmp=BIO_new(BIO_f_cipher())) == NULL)
			{
			PKCS7err(PKCS7_F_PKCS7_DATADECODE,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) {
				PKCS7err(PKCS7_F_PKCS7_DATADECODE,
				      PKCS7_R_NO_RECIPIENT_MATCHES_CERTIFICATE);
				goto err;
			}
		}

		jj=EVP_PKEY_size(pkey);
		tmp=(unsigned char *)OPENSSL_malloc(jj+10);
		if (tmp == NULL)
			{
			PKCS7err(PKCS7_F_PKCS7_DATADECODE,ERR_R_MALLOC_FAILURE);
			goto err;
			}

		/* If we haven't got a certificate try each ri in turn */

		if (pcert == NULL)
			{
			for (i=0; i<sk_PKCS7_RECIP_INFO_num(rsk); i++)
				{
				ri=sk_PKCS7_RECIP_INFO_value(rsk,i);
				jj=EVP_PKEY_decrypt(tmp,
					M_ASN1_STRING_data(ri->enc_key),
					M_ASN1_STRING_length(ri->enc_key),
						pkey);
				if (jj > 0)
					break;
				ERR_clear_error();
				ri = NULL;
				}
			if (ri == NULL)
				{
				PKCS7err(PKCS7_F_PKCS7_DATADECODE,
				      PKCS7_R_NO_RECIPIENT_MATCHES_KEY);
				goto err;
				}
			}
		else
			{
			jj=EVP_PKEY_decrypt(tmp,
				M_ASN1_STRING_data(ri->enc_key),
				M_ASN1_STRING_length(ri->enc_key), pkey);
			if (jj <= 0)
				{
				PKCS7err(PKCS7_F_PKCS7_DATADECODE,
								ERR_R_EVP_LIB);
				goto err;
				}
			}

		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;

		if (jj != 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, jj))
				{
				PKCS7err(PKCS7_F_PKCS7_DATADECODE,
					PKCS7_R_DECRYPTED_KEY_IS_WRONG_LENGTH);
				goto err;
				}
		} 
		if (EVP_CipherInit_ex(evp_ctx,NULL,NULL,tmp,NULL,0) <= 0)
			goto err;

		OPENSSL_cleanse(tmp,jj);

		if (out == NULL)
			out=etmp;
		else
			BIO_push(out,etmp);
		etmp=NULL;
		}

#if 1
	if (PKCS7_is_detached(p7) || (in_bio != NULL))
		{
		bio=in_bio;
		}
	else 
		{
#if 0
		bio=BIO_new(BIO_s_mem());
		/* We need to set this so that when we have read all
		 * the data, the encrypt BIO, if present, will read
		 * EOF and encode the last few bytes */
		BIO_set_mem_eof_return(bio,0);

		if (data_body->length > 0)
			BIO_write(bio,(char *)data_body->data,data_body->length);
#else
		if (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;
#endif
		}
	BIO_push(out,bio);
	bio=NULL;
#endif
	if (0)
		{
err:
		if (out != NULL) BIO_free_all(out);
		if (btmp != NULL) BIO_free_all(btmp);
		if (etmp != NULL) BIO_free_all(etmp);
		if (bio != NULL) BIO_free_all(bio);
		out=NULL;
		}
	if (tmp != NULL)
		OPENSSL_free(tmp);
	return(out);
	}

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)
			{
			PKCS7err(PKCS7_F_PKCS7_FIND_DIGEST,PKCS7_R_UNABLE_TO_FIND_MESSAGE_DIGEST);
			return NULL;	
			}
		BIO_get_md_ctx(bio,pmd);
		if (*pmd == NULL)
			{
			PKCS7err(PKCS7_F_PKCS7_FIND_DIGEST,ERR_R_INTERNAL_ERROR);
			return NULL;
			}	
		if (EVP_MD_CTX_type(*pmd) == nid)
			return bio;
		bio=BIO_next(bio);
		}
	return NULL;
	}

int PKCS7_dataFinal(PKCS7 *p7, BIO *bio)
	{
	int ret=0;
	int i,j;
	BIO *btmp;
	BUF_MEM *buf_mem=NULL;
	BUF_MEM *buf=NULL;
	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;

	EVP_MD_CTX_init(&ctx_tmp);
	i=OBJ_obj2nid(p7->type);
	p7->state=PKCS7_S_HEADER;

	switch (i)
		{
	case NID_pkcs7_signedAndEnveloped:
		/* XXXXXXXXXXXXXXXX */
		si_sk=p7->d.signed_and_enveloped->signer_info;
		if (!(os=M_ASN1_OCTET_STRING_new()))
			{
			PKCS7err(PKCS7_F_PKCS7_DATAFINAL,ERR_R_MALLOC_FAILURE);
			goto err;
			}
		p7->d.signed_and_enveloped->enc_data->enc_data=os;
		break;
	case NID_pkcs7_enveloped:
		/* XXXXXXXXXXXXXXXX */
		if (!(os=M_ASN1_OCTET_STRING_new()))
			{
			PKCS7err(PKCS7_F_PKCS7_DATAFINAL,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 detached data then the content is excluded */
		if(PKCS7_type_is_data(p7->d.sign->contents) && p7->detached) {
			M_ASN1_OCTET_STRING_free(os);
			p7->d.sign->contents->d.data = NULL;
		}
		break;

	case NID_pkcs7_digest:
		os=PKCS7_get_octet_string(p7->d.digest->contents);
		/* If detached data then the content is excluded */
		if(PKCS7_type_is_data(p7->d.digest->contents) && p7->detached)
			{
			M_ASN1_OCTET_STRING_free(os);
			p7->d.digest->contents->d.data = NULL;
			}
		break;

		}

	if (si_sk != NULL)
		{
		if ((buf=BUF_MEM_new()) == NULL)
			{
			PKCS7err(PKCS7_F_PKCS7_DATAFINAL,ERR_R_BIO_LIB);
			goto err;
			}
		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);

			btmp=bio;

			btmp = PKCS7_find_digest(&mdc, btmp, j);

			if (btmp == NULL)
				goto err;

			/* We now have the EVP_MD_CTX, lets do the
			 * signing. */
			EVP_MD_CTX_copy_ex(&ctx_tmp,mdc);
			if (!BUF_MEM_grow_clean(buf,EVP_PKEY_size(si->pkey)))
				{
				PKCS7err(PKCS7_F_PKCS7_DATAFINAL,ERR_R_BIO_LIB);
				goto err;
				}

			sk=si->auth_attr;

			/* If there are attributes, we add the digest
			 * attribute and only sign the attributes */
			if ((sk != NULL) && (sk_X509_ATTRIBUTE_num(sk) != 0))
				{
				unsigned char md_data[EVP_MAX_MD_SIZE], *abuf=NULL;
				unsigned int md_len, alen;
				ASN1_OCTET_STRING *digest;
				ASN1_UTCTIME *sign_time;
				const EVP_MD *md_tmp;

				/* Add signing time if not already present */
				if (!PKCS7_get_signed_attribute(si,
							NID_pkcs9_signingTime))
					{
					if (!(sign_time=X509_gmtime_adj(NULL,0)))
						{
						PKCS7err(PKCS7_F_PKCS7_DATAFINAL,
							ERR_R_MALLOC_FAILURE);
						goto err;
						}
					if (!PKCS7_add_signed_attribute(si,
						NID_pkcs9_signingTime,
						V_ASN1_UTCTIME,sign_time))
						{
						M_ASN1_UTCTIME_free(sign_time);
						goto err;
						}
					}

				/* Add digest */
				md_tmp=EVP_MD_CTX_md(&ctx_tmp);
				EVP_DigestFinal_ex(&ctx_tmp,md_data,&md_len);
				if (!(digest=M_ASN1_OCTET_STRING_new()))
					{
					PKCS7err(PKCS7_F_PKCS7_DATAFINAL,
						ERR_R_MALLOC_FAILURE);
					goto err;
					}
				if (!M_ASN1_OCTET_STRING_set(digest,md_data,
								md_len))
					{
					PKCS7err(PKCS7_F_PKCS7_DATAFINAL,
						ERR_R_MALLOC_FAILURE);
					M_ASN1_OCTET_STRING_free(digest);
					goto err;
					}
				if (!PKCS7_add_signed_attribute(si,
					NID_pkcs9_messageDigest,
					V_ASN1_OCTET_STRING,digest))
					{
					M_ASN1_OCTET_STRING_free(digest);
					goto err;
					}

				/* Now sign the attributes */
				EVP_SignInit_ex(&ctx_tmp,md_tmp,NULL);
				alen = ASN1_item_i2d((ASN1_VALUE *)sk,&abuf,
							ASN1_ITEM_rptr(PKCS7_ATTR_SIGN));
				if(!abuf) goto err;
				EVP_SignUpdate(&ctx_tmp,abuf,alen);
				OPENSSL_free(abuf);
				}

#ifndef OPENSSL_NO_DSA
			if (si->pkey->type == EVP_PKEY_DSA)
				ctx_tmp.digest=EVP_dss1();
#endif
#ifndef OPENSSL_NO_ECDSA
 			if (si->pkey->type == EVP_PKEY_EC)
 				ctx_tmp.digest=EVP_ecdsa();
#endif

			if (!EVP_SignFinal(&ctx_tmp,(unsigned char *)buf->data,
				(unsigned int *)&buf->length,si->pkey))
				{
				PKCS7err(PKCS7_F_PKCS7_DATAFINAL,ERR_R_EVP_LIB);
				goto err;
				}
			if (!ASN1_STRING_set(si->enc_digest,
				(unsigned char *)buf->data,buf->length))
				{
				PKCS7err(PKCS7_F_PKCS7_DATAFINAL,ERR_R_ASN1_LIB);
				goto err;
				}
			}
		}
	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;
		EVP_DigestFinal_ex(mdc,md_data,&md_len);
		M_ASN1_OCTET_STRING_set(p7->d.digest->digest, md_data, md_len);
		}

	if (!PKCS7_is_detached(p7))
		{
		btmp=BIO_find_type(bio,BIO_TYPE_MEM);
		if (btmp == NULL)
			{
			PKCS7err(PKCS7_F_PKCS7_DATAFINAL,PKCS7_R_UNABLE_TO_FIND_MEM_BIO);
			goto err;
			}
		BIO_get_mem_ptr(btmp,&buf_mem);
		/* 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);
		os->data = (unsigned char *)buf_mem->data;
		os->length = buf_mem->length;
#if 0
		M_ASN1_OCTET_STRING_set(os,
			(unsigned char *)buf_mem->data,buf_mem->length);
#endif
		}
	ret=1;
err:
	EVP_MD_CTX_cleanup(&ctx_tmp);
	if (buf != NULL) BUF_MEM_free(buf);
	return(ret);
	}

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 (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
		{
		PKCS7err(PKCS7_F_PKCS7_DATAVERIFY,PKCS7_R_WRONG_PKCS7_TYPE);
		goto err;
		}
	/* XXXXXXXXXXXXXXXXXXXXXXX */
	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)
		{
		PKCS7err(PKCS7_F_PKCS7_DATAVERIFY,PKCS7_R_UNABLE_TO_FIND_CERTIFICATE);
		goto err;
		}

	/* Lets verify */
	if(!X509_STORE_CTX_init(ctx,cert_store,x509,cert))
		{
		PKCS7err(PKCS7_F_PKCS7_DATAVERIFY,ERR_R_X509_LIB);
		goto err;
		}
	X509_STORE_CTX_set_purpose(ctx, X509_PURPOSE_SMIME_SIGN);
	i=X509_verify_cert(ctx);
	if (i <= 0) 
		{
		PKCS7err(PKCS7_F_PKCS7_DATAVERIFY,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;
	}

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_init(&mdc_tmp);

	if (!PKCS7_type_is_signed(p7) && 
				!PKCS7_type_is_signedAndEnveloped(p7)) {
		PKCS7err(PKCS7_F_PKCS7_SIGNATUREVERIFY,
						PKCS7_R_WRONG_PKCS7_TYPE);
		goto err;
	}

	md_type=OBJ_obj2nid(si->digest_alg->algorithm);

	btmp=bio;
	for (;;)
		{
		if ((btmp == NULL) ||
			((btmp=BIO_find_type(btmp,BIO_TYPE_MD)) == NULL))
			{
			PKCS7err(PKCS7_F_PKCS7_SIGNATUREVERIFY,
					PKCS7_R_UNABLE_TO_FIND_MESSAGE_DIGEST);
			goto err;
			}
		BIO_get_md_ctx(btmp,&mdc);
		if (mdc == NULL)
			{
			PKCS7err(PKCS7_F_PKCS7_SIGNATUREVERIFY,
							ERR_R_INTERNAL_ERROR);
			goto err;
			}
		if (EVP_MD_CTX_type(mdc) == md_type)
			break;
		/* Workaround for some broken clients that put the signature
		 * OID instead of the digest OID in digest_alg->algorithm
		 */
		if (EVP_MD_pkey_type(EVP_MD_CTX_md(mdc)) == md_type)
			break;
		btmp=BIO_next(btmp);
		}

	/* mdc is the digest ctx that we want, unless there are attributes,
	 * in which case the digest is the signed attributes */
	EVP_MD_CTX_copy_ex(&mdc_tmp,mdc);

	sk=si->auth_attr;
	if ((sk != NULL) && (sk_X509_ATTRIBUTE_num(sk) != 0))
		{
		unsigned char md_dat[EVP_MAX_MD_SIZE], *abuf = NULL;
                unsigned int md_len, alen;
		ASN1_OCTET_STRING *message_digest;

		EVP_DigestFinal_ex(&mdc_tmp,md_dat,&md_len);
		message_digest=PKCS7_digest_from_attributes(sk);
		if (!message_digest)
			{
			PKCS7err(PKCS7_F_PKCS7_SIGNATUREVERIFY,
					PKCS7_R_UNABLE_TO_FIND_MESSAGE_DIGEST);
			goto err;
			}
		if ((message_digest->length != (int)md_len) ||
			(memcmp(message_digest->data,md_dat,md_len)))
			{
#if 0
{
int ii;
for (ii=0; ii<message_digest->length; ii++)
	printf("%02X",message_digest->data[ii]); printf(" sent\n");
for (ii=0; ii<md_len; ii++) printf("%02X",md_dat[ii]); printf(" calc\n");
}
#endif
			PKCS7err(PKCS7_F_PKCS7_SIGNATUREVERIFY,
							PKCS7_R_DIGEST_FAILURE);
			ret= -1;
			goto err;
			}

		EVP_VerifyInit_ex(&mdc_tmp,EVP_get_digestbynid(md_type), NULL);

		alen = ASN1_item_i2d((ASN1_VALUE *)sk, &abuf,
						ASN1_ITEM_rptr(PKCS7_ATTR_VERIFY));
		EVP_VerifyUpdate(&mdc_tmp, abuf, alen);

		OPENSSL_free(abuf);
		}

	os=si->enc_digest;
	pkey = X509_get_pubkey(x509);
	if (!pkey)
		{
		ret = -1;
		goto err;
		}
#ifndef OPENSSL_NO_DSA
	if(pkey->type == EVP_PKEY_DSA) mdc_tmp.digest=EVP_dss1();
#endif
#ifndef OPENSSL_NO_ECDSA
	if (pkey->type == EVP_PKEY_EC) mdc_tmp.digest=EVP_ecdsa();
#endif

	i=EVP_VerifyFinal(&mdc_tmp,os->data,os->length, pkey);
	EVP_PKEY_free(pkey);
	if (i <= 0)
		{
		PKCS7err(PKCS7_F_PKCS7_SIGNATUREVERIFY,
						PKCS7_R_SIGNATURE_FAILURE);
		ret= -1;
		goto err;
		}
	else
		ret=1;
err:
	EVP_MD_CTX_cleanup(&mdc_tmp);
	return(ret);
	}

PKCS7_ISSUER_AND_SERIAL *PKCS7_get_issuer_and_serial(PKCS7 *p7, int idx)
	{
	STACK_OF(PKCS7_RECIP_INFO) *rsk;
	PKCS7_RECIP_INFO *ri;
	int i;

	i=OBJ_obj2nid(p7->type);
	if (i != NID_pkcs7_signedAndEnveloped)
		return NULL;
	if (p7->d.signed_and_enveloped == NULL)
		return NULL;
	rsk=p7->d.signed_and_enveloped->recipientinfo;
	if (rsk == NULL)
		return NULL;
	ri=sk_PKCS7_RECIP_INFO_value(rsk,0);
	if (sk_PKCS7_RECIP_INFO_num(rsk) <= idx) return(NULL);
	ri=sk_PKCS7_RECIP_INFO_value(rsk,idx);
	return(ri->issuer_and_serial);
	}

ASN1_TYPE *PKCS7_get_signed_attribute(PKCS7_SIGNER_INFO *si, int nid)
	{
	return(get_attribute(si->auth_attr,nid));
	}

ASN1_TYPE *PKCS7_get_attribute(PKCS7_SIGNER_INFO *si, int nid)
	{
	return(get_attribute(si->unauth_attr,nid));
	}

static ASN1_TYPE *get_attribute(STACK_OF(X509_ATTRIBUTE) *sk, int nid)
	{
	int i;
	X509_ATTRIBUTE *xa;
	ASN1_OBJECT *o;

	o=OBJ_nid2obj(nid);
	if (!o || !sk) return(NULL);
	for (i=0; i<sk_X509_ATTRIBUTE_num(sk); i++)
		{
		xa=sk_X509_ATTRIBUTE_value(sk,i);
		if (OBJ_cmp(xa->object,o) == 0)
			{
			if (!xa->single && sk_ASN1_TYPE_num(xa->value.set))
				return(sk_ASN1_TYPE_value(xa->value.set,0));
			else
				return(NULL);
			}
		}
	return(NULL);
	}

ASN1_OCTET_STRING *PKCS7_digest_from_attributes(STACK_OF(X509_ATTRIBUTE) *sk)
{
	ASN1_TYPE *astype;
	if(!(astype = get_attribute(sk, NID_pkcs9_messageDigest))) return NULL;
	return astype->value.octet_string;
}

int PKCS7_set_signed_attributes(PKCS7_SIGNER_INFO *p7si,
				STACK_OF(X509_ATTRIBUTE) *sk)
	{
	int i;

	if (p7si->auth_attr != NULL)
		sk_X509_ATTRIBUTE_pop_free(p7si->auth_attr,X509_ATTRIBUTE_free);
	p7si->auth_attr=sk_X509_ATTRIBUTE_dup(sk);
	if (p7si->auth_attr == NULL)
		return 0;
	for (i=0; i<sk_X509_ATTRIBUTE_num(sk); i++)
		{
		if ((sk_X509_ATTRIBUTE_set(p7si->auth_attr,i,
			X509_ATTRIBUTE_dup(sk_X509_ATTRIBUTE_value(sk,i))))
		    == NULL)
			return(0);
		}
	return(1);
	}

int PKCS7_set_attributes(PKCS7_SIGNER_INFO *p7si, STACK_OF(X509_ATTRIBUTE) *sk)
	{
	int i;

	if (p7si->unauth_attr != NULL)
		sk_X509_ATTRIBUTE_pop_free(p7si->unauth_attr,
					   X509_ATTRIBUTE_free);
	p7si->unauth_attr=sk_X509_ATTRIBUTE_dup(sk);
	if (p7si->unauth_attr == NULL)
		return 0;
	for (i=0; i<sk_X509_ATTRIBUTE_num(sk); i++)
		{
		if ((sk_X509_ATTRIBUTE_set(p7si->unauth_attr,i,
                        X509_ATTRIBUTE_dup(sk_X509_ATTRIBUTE_value(sk,i))))
		    == NULL)
			return(0);
		}
	return(1);
	}

int PKCS7_add_signed_attribute(PKCS7_SIGNER_INFO *p7si, int nid, int atrtype,
	     void *value)
	{
	return(add_attribute(&(p7si->auth_attr),nid,atrtype,value));
	}

int PKCS7_add_attribute(PKCS7_SIGNER_INFO *p7si, int nid, int atrtype,
	     void *value)
	{
	return(add_attribute(&(p7si->unauth_attr),nid,atrtype,value));
	}

static int add_attribute(STACK_OF(X509_ATTRIBUTE) **sk, int nid, int atrtype,
			 void *value)
	{
	X509_ATTRIBUTE *attr=NULL;

	if (*sk == NULL)
		{
		if (!(*sk = sk_X509_ATTRIBUTE_new_null()))
			return 0;
new_attrib:
		if (!(attr=X509_ATTRIBUTE_create(nid,atrtype,value)))
			return 0;
		if (!sk_X509_ATTRIBUTE_push(*sk,attr))
			{
			X509_ATTRIBUTE_free(attr);
			return 0;
			}
		}
	else
		{
		int i;

		for (i=0; i<sk_X509_ATTRIBUTE_num(*sk); i++)
			{
			attr=sk_X509_ATTRIBUTE_value(*sk,i);
			if (OBJ_obj2nid(attr->object) == nid)
				{
				X509_ATTRIBUTE_free(attr);
				attr=X509_ATTRIBUTE_create(nid,atrtype,value);
				if (attr == NULL)
					return 0;
				if (!sk_X509_ATTRIBUTE_set(*sk,i,attr))
					{
					X509_ATTRIBUTE_free(attr);
					return 0;
					}
				goto end;
				}
			}
		goto new_attrib;
		}
end:
	return(1);
	}


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