freebsd-dev/crypto/openssl/apps/smime.c

592 lines
18 KiB
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/* smime.c */
/* Written by Dr Stephen N Henson (shenson@bigfoot.com) for the OpenSSL
* project 1999.
*/
/* ====================================================================
* Copyright (c) 1999 The OpenSSL Project. All rights reserved.
*
* 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 above 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 acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
*
* 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
* endorse or promote products derived from this software without
* prior written permission. For written permission, please contact
* licensing@OpenSSL.org.
*
* 5. Products derived from this software may not be called "OpenSSL"
* nor may "OpenSSL" appear in their names without prior written
* permission of the OpenSSL Project.
*
* 6. Redistributions of any form whatsoever must retain the following
* acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
*
* THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
* EXPRESSED 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 OpenSSL PROJECT OR
* ITS 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.
* ====================================================================
*
* This product includes cryptographic software written by Eric Young
* (eay@cryptsoft.com). This product includes software written by Tim
* Hudson (tjh@cryptsoft.com).
*
*/
/* S/MIME utility function */
#include <stdio.h>
#include <string.h>
#include "apps.h"
#include <openssl/crypto.h>
#include <openssl/pem.h>
#include <openssl/err.h>
#undef PROG
#define PROG smime_main
static int save_certs(char *signerfile, STACK_OF(X509) *signers);
#define SMIME_OP 0x10
#define SMIME_ENCRYPT (1 | SMIME_OP)
#define SMIME_DECRYPT 2
#define SMIME_SIGN (3 | SMIME_OP)
#define SMIME_VERIFY 4
#define SMIME_PK7OUT 5
int MAIN(int, char **);
int MAIN(int argc, char **argv)
{
ENGINE *e = NULL;
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int operation = 0;
int ret = 0;
char **args;
char *inmode = "r", *outmode = "w";
char *infile = NULL, *outfile = NULL;
char *signerfile = NULL, *recipfile = NULL;
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char *certfile = NULL, *keyfile = NULL, *contfile=NULL;
const EVP_CIPHER *cipher = NULL;
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PKCS7 *p7 = NULL;
X509_STORE *store = NULL;
X509 *cert = NULL, *recip = NULL, *signer = NULL;
EVP_PKEY *key = NULL;
STACK_OF(X509) *encerts = NULL, *other = NULL;
BIO *in = NULL, *out = NULL, *indata = NULL;
int badarg = 0;
int flags = PKCS7_DETACHED, store_flags = 0;
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char *to = NULL, *from = NULL, *subject = NULL;
char *CAfile = NULL, *CApath = NULL;
char *passargin = NULL, *passin = NULL;
char *inrand = NULL;
int need_rand = 0;
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int informat = FORMAT_SMIME, outformat = FORMAT_SMIME;
int keyform = FORMAT_PEM;
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#ifndef OPENSSL_NO_ENGINE
char *engine=NULL;
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#endif
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args = argv + 1;
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ret = 1;
apps_startup();
if (bio_err == NULL)
if ((bio_err = BIO_new(BIO_s_file())) != NULL)
BIO_set_fp(bio_err, stderr, BIO_NOCLOSE|BIO_FP_TEXT);
if (!load_config(bio_err, NULL))
goto end;
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while (!badarg && *args && *args[0] == '-') {
if (!strcmp (*args, "-encrypt")) operation = SMIME_ENCRYPT;
else if (!strcmp (*args, "-decrypt")) operation = SMIME_DECRYPT;
else if (!strcmp (*args, "-sign")) operation = SMIME_SIGN;
else if (!strcmp (*args, "-verify")) operation = SMIME_VERIFY;
else if (!strcmp (*args, "-pk7out")) operation = SMIME_PK7OUT;
#ifndef OPENSSL_NO_DES
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else if (!strcmp (*args, "-des3"))
cipher = EVP_des_ede3_cbc();
else if (!strcmp (*args, "-des"))
cipher = EVP_des_cbc();
#endif
#ifndef OPENSSL_NO_RC2
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else if (!strcmp (*args, "-rc2-40"))
cipher = EVP_rc2_40_cbc();
else if (!strcmp (*args, "-rc2-128"))
cipher = EVP_rc2_cbc();
else if (!strcmp (*args, "-rc2-64"))
cipher = EVP_rc2_64_cbc();
#endif
#ifndef OPENSSL_NO_AES
else if (!strcmp(*args,"-aes128"))
cipher = EVP_aes_128_cbc();
else if (!strcmp(*args,"-aes192"))
cipher = EVP_aes_192_cbc();
else if (!strcmp(*args,"-aes256"))
cipher = EVP_aes_256_cbc();
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#endif
else if (!strcmp (*args, "-text"))
flags |= PKCS7_TEXT;
else if (!strcmp (*args, "-nointern"))
flags |= PKCS7_NOINTERN;
else if (!strcmp (*args, "-noverify"))
flags |= PKCS7_NOVERIFY;
else if (!strcmp (*args, "-nochain"))
flags |= PKCS7_NOCHAIN;
else if (!strcmp (*args, "-nocerts"))
flags |= PKCS7_NOCERTS;
else if (!strcmp (*args, "-noattr"))
flags |= PKCS7_NOATTR;
else if (!strcmp (*args, "-nodetach"))
flags &= ~PKCS7_DETACHED;
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else if (!strcmp (*args, "-nosmimecap"))
flags |= PKCS7_NOSMIMECAP;
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else if (!strcmp (*args, "-binary"))
flags |= PKCS7_BINARY;
else if (!strcmp (*args, "-nosigs"))
flags |= PKCS7_NOSIGS;
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else if (!strcmp (*args, "-nooldmime"))
flags |= PKCS7_NOOLDMIMETYPE;
else if (!strcmp (*args, "-crlfeol"))
flags |= PKCS7_CRLFEOL;
else if (!strcmp (*args, "-crl_check"))
store_flags |= X509_V_FLAG_CRL_CHECK;
else if (!strcmp (*args, "-crl_check_all"))
store_flags |= X509_V_FLAG_CRL_CHECK|X509_V_FLAG_CRL_CHECK_ALL;
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else if (!strcmp(*args,"-rand")) {
if (args[1]) {
args++;
inrand = *args;
} else badarg = 1;
need_rand = 1;
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#ifndef OPENSSL_NO_ENGINE
} else if (!strcmp(*args,"-engine")) {
if (args[1]) {
args++;
engine = *args;
} else badarg = 1;
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#endif
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} else if (!strcmp(*args,"-passin")) {
if (args[1]) {
args++;
passargin = *args;
} else badarg = 1;
} else if (!strcmp (*args, "-to")) {
if (args[1]) {
args++;
to = *args;
} else badarg = 1;
} else if (!strcmp (*args, "-from")) {
if (args[1]) {
args++;
from = *args;
} else badarg = 1;
} else if (!strcmp (*args, "-subject")) {
if (args[1]) {
args++;
subject = *args;
} else badarg = 1;
} else if (!strcmp (*args, "-signer")) {
if (args[1]) {
args++;
signerfile = *args;
} else badarg = 1;
} else if (!strcmp (*args, "-recip")) {
if (args[1]) {
args++;
recipfile = *args;
} else badarg = 1;
} else if (!strcmp (*args, "-inkey")) {
if (args[1]) {
args++;
keyfile = *args;
} else badarg = 1;
} else if (!strcmp (*args, "-keyform")) {
if (args[1]) {
args++;
keyform = str2fmt(*args);
} else badarg = 1;
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} else if (!strcmp (*args, "-certfile")) {
if (args[1]) {
args++;
certfile = *args;
} else badarg = 1;
} else if (!strcmp (*args, "-CAfile")) {
if (args[1]) {
args++;
CAfile = *args;
} else badarg = 1;
} else if (!strcmp (*args, "-CApath")) {
if (args[1]) {
args++;
CApath = *args;
} else badarg = 1;
} else if (!strcmp (*args, "-in")) {
if (args[1]) {
args++;
infile = *args;
} else badarg = 1;
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} else if (!strcmp (*args, "-inform")) {
if (args[1]) {
args++;
informat = str2fmt(*args);
} else badarg = 1;
} else if (!strcmp (*args, "-outform")) {
if (args[1]) {
args++;
outformat = str2fmt(*args);
} else badarg = 1;
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} else if (!strcmp (*args, "-out")) {
if (args[1]) {
args++;
outfile = *args;
} else badarg = 1;
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} else if (!strcmp (*args, "-content")) {
if (args[1]) {
args++;
contfile = *args;
} else badarg = 1;
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} else badarg = 1;
args++;
}
if(operation == SMIME_SIGN) {
if(!signerfile) {
BIO_printf(bio_err, "No signer certificate specified\n");
badarg = 1;
}
need_rand = 1;
} else if(operation == SMIME_DECRYPT) {
if(!recipfile) {
BIO_printf(bio_err, "No recipient certificate and key specified\n");
badarg = 1;
}
} else if(operation == SMIME_ENCRYPT) {
if(!*args) {
BIO_printf(bio_err, "No recipient(s) certificate(s) specified\n");
badarg = 1;
}
need_rand = 1;
} else if(!operation) badarg = 1;
if (badarg) {
BIO_printf (bio_err, "Usage smime [options] cert.pem ...\n");
BIO_printf (bio_err, "where options are\n");
BIO_printf (bio_err, "-encrypt encrypt message\n");
BIO_printf (bio_err, "-decrypt decrypt encrypted message\n");
BIO_printf (bio_err, "-sign sign message\n");
BIO_printf (bio_err, "-verify verify signed message\n");
BIO_printf (bio_err, "-pk7out output PKCS#7 structure\n");
#ifndef OPENSSL_NO_DES
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BIO_printf (bio_err, "-des3 encrypt with triple DES\n");
BIO_printf (bio_err, "-des encrypt with DES\n");
#endif
#ifndef OPENSSL_NO_RC2
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BIO_printf (bio_err, "-rc2-40 encrypt with RC2-40 (default)\n");
BIO_printf (bio_err, "-rc2-64 encrypt with RC2-64\n");
BIO_printf (bio_err, "-rc2-128 encrypt with RC2-128\n");
#endif
#ifndef OPENSSL_NO_AES
BIO_printf (bio_err, "-aes128, -aes192, -aes256\n");
BIO_printf (bio_err, " encrypt PEM output with cbc aes\n");
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#endif
BIO_printf (bio_err, "-nointern don't search certificates in message for signer\n");
BIO_printf (bio_err, "-nosigs don't verify message signature\n");
BIO_printf (bio_err, "-noverify don't verify signers certificate\n");
BIO_printf (bio_err, "-nocerts don't include signers certificate when signing\n");
BIO_printf (bio_err, "-nodetach use opaque signing\n");
BIO_printf (bio_err, "-noattr don't include any signed attributes\n");
BIO_printf (bio_err, "-binary don't translate message to text\n");
BIO_printf (bio_err, "-certfile file other certificates file\n");
BIO_printf (bio_err, "-signer file signer certificate file\n");
BIO_printf (bio_err, "-recip file recipient certificate file for decryption\n");
BIO_printf (bio_err, "-in file input file\n");
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BIO_printf (bio_err, "-inform arg input format SMIME (default), PEM or DER\n");
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BIO_printf (bio_err, "-inkey file input private key (if not signer or recipient)\n");
BIO_printf (bio_err, "-keyform arg input private key format (PEM or ENGINE)\n");
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BIO_printf (bio_err, "-out file output file\n");
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BIO_printf (bio_err, "-outform arg output format SMIME (default), PEM or DER\n");
BIO_printf (bio_err, "-content file supply or override content for detached signature\n");
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BIO_printf (bio_err, "-to addr to address\n");
BIO_printf (bio_err, "-from ad from address\n");
BIO_printf (bio_err, "-subject s subject\n");
BIO_printf (bio_err, "-text include or delete text MIME headers\n");
BIO_printf (bio_err, "-CApath dir trusted certificates directory\n");
BIO_printf (bio_err, "-CAfile file trusted certificates file\n");
BIO_printf (bio_err, "-crl_check check revocation status of signer's certificate using CRLs\n");
BIO_printf (bio_err, "-crl_check_all check revocation status of signer's certificate chain using CRLs\n");
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#ifndef OPENSSL_NO_ENGINE
BIO_printf (bio_err, "-engine e use engine e, possibly a hardware device.\n");
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#endif
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BIO_printf (bio_err, "-passin arg input file pass phrase source\n");
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BIO_printf(bio_err, "-rand file%cfile%c...\n", LIST_SEPARATOR_CHAR, LIST_SEPARATOR_CHAR);
BIO_printf(bio_err, " load the file (or the files in the directory) into\n");
BIO_printf(bio_err, " the random number generator\n");
BIO_printf (bio_err, "cert.pem recipient certificate(s) for encryption\n");
goto end;
}
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#ifndef OPENSSL_NO_ENGINE
e = setup_engine(bio_err, engine, 0);
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#endif
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if(!app_passwd(bio_err, passargin, NULL, &passin, NULL)) {
BIO_printf(bio_err, "Error getting password\n");
goto end;
}
if (need_rand) {
app_RAND_load_file(NULL, bio_err, (inrand != NULL));
if (inrand != NULL)
BIO_printf(bio_err,"%ld semi-random bytes loaded\n",
app_RAND_load_files(inrand));
}
ret = 2;
if(operation != SMIME_SIGN) flags &= ~PKCS7_DETACHED;
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if(operation & SMIME_OP) {
if(flags & PKCS7_BINARY) inmode = "rb";
if(outformat == FORMAT_ASN1) outmode = "wb";
} else {
if(flags & PKCS7_BINARY) outmode = "wb";
if(informat == FORMAT_ASN1) inmode = "rb";
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}
if(operation == SMIME_ENCRYPT) {
if (!cipher) {
#ifndef OPENSSL_NO_RC2
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cipher = EVP_rc2_40_cbc();
#else
BIO_printf(bio_err, "No cipher selected\n");
goto end;
#endif
}
encerts = sk_X509_new_null();
while (*args) {
if(!(cert = load_cert(bio_err,*args,FORMAT_PEM,
NULL, e, "recipient certificate file"))) {
#if 0 /* An appropriate message is already printed */
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BIO_printf(bio_err, "Can't read recipient certificate file %s\n", *args);
#endif
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goto end;
}
sk_X509_push(encerts, cert);
cert = NULL;
args++;
}
}
if(signerfile && (operation == SMIME_SIGN)) {
if(!(signer = load_cert(bio_err,signerfile,FORMAT_PEM, NULL,
e, "signer certificate"))) {
#if 0 /* An appropri message has already been printed */
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BIO_printf(bio_err, "Can't read signer certificate file %s\n", signerfile);
#endif
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goto end;
}
}
if(certfile) {
if(!(other = load_certs(bio_err,certfile,FORMAT_PEM, NULL,
e, "certificate file"))) {
#if 0 /* An appropriate message has already been printed */
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BIO_printf(bio_err, "Can't read certificate file %s\n", certfile);
#endif
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ERR_print_errors(bio_err);
goto end;
}
}
if(recipfile && (operation == SMIME_DECRYPT)) {
if(!(recip = load_cert(bio_err,recipfile,FORMAT_PEM,NULL,
e, "recipient certificate file"))) {
#if 0 /* An appropriate message has alrady been printed */
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BIO_printf(bio_err, "Can't read recipient certificate file %s\n", recipfile);
#endif
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ERR_print_errors(bio_err);
goto end;
}
}
if(operation == SMIME_DECRYPT) {
if(!keyfile) keyfile = recipfile;
} else if(operation == SMIME_SIGN) {
if(!keyfile) keyfile = signerfile;
} else keyfile = NULL;
if(keyfile) {
key = load_key(bio_err, keyfile, keyform, 0, passin, e,
"signing key file");
if (!key) {
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goto end;
}
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}
if (infile) {
if (!(in = BIO_new_file(infile, inmode))) {
BIO_printf (bio_err,
"Can't open input file %s\n", infile);
goto end;
}
} else in = BIO_new_fp(stdin, BIO_NOCLOSE);
if (outfile) {
if (!(out = BIO_new_file(outfile, outmode))) {
BIO_printf (bio_err,
"Can't open output file %s\n", outfile);
goto end;
}
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} else {
out = BIO_new_fp(stdout, BIO_NOCLOSE);
#ifdef OPENSSL_SYS_VMS
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{
BIO *tmpbio = BIO_new(BIO_f_linebuffer());
out = BIO_push(tmpbio, out);
}
#endif
}
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if(operation == SMIME_VERIFY) {
if(!(store = setup_verify(bio_err, CAfile, CApath))) goto end;
X509_STORE_set_flags(store, store_flags);
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}
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ret = 3;
if(operation == SMIME_ENCRYPT) {
p7 = PKCS7_encrypt(encerts, in, cipher, flags);
} else if(operation == SMIME_SIGN) {
p7 = PKCS7_sign(signer, key, other, in, flags);
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if (BIO_reset(in) != 0 && (flags & PKCS7_DETACHED)) {
BIO_printf(bio_err, "Can't rewind input file\n");
goto end;
}
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} else {
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if(informat == FORMAT_SMIME)
p7 = SMIME_read_PKCS7(in, &indata);
else if(informat == FORMAT_PEM)
p7 = PEM_read_bio_PKCS7(in, NULL, NULL, NULL);
else if(informat == FORMAT_ASN1)
p7 = d2i_PKCS7_bio(in, NULL);
else {
BIO_printf(bio_err, "Bad input format for PKCS#7 file\n");
goto end;
}
if(!p7) {
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BIO_printf(bio_err, "Error reading S/MIME message\n");
goto end;
}
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if(contfile) {
BIO_free(indata);
if(!(indata = BIO_new_file(contfile, "rb"))) {
BIO_printf(bio_err, "Can't read content file %s\n", contfile);
goto end;
}
}
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}
if(!p7) {
BIO_printf(bio_err, "Error creating PKCS#7 structure\n");
goto end;
}
ret = 4;
if(operation == SMIME_DECRYPT) {
if(!PKCS7_decrypt(p7, key, recip, out, flags)) {
BIO_printf(bio_err, "Error decrypting PKCS#7 structure\n");
goto end;
}
} else if(operation == SMIME_VERIFY) {
STACK_OF(X509) *signers;
if(PKCS7_verify(p7, other, store, indata, out, flags)) {
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BIO_printf(bio_err, "Verification successful\n");
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} else {
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BIO_printf(bio_err, "Verification failure\n");
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goto end;
}
signers = PKCS7_get0_signers(p7, other, flags);
if(!save_certs(signerfile, signers)) {
BIO_printf(bio_err, "Error writing signers to %s\n",
signerfile);
ret = 5;
goto end;
}
sk_X509_free(signers);
} else if(operation == SMIME_PK7OUT) {
PEM_write_bio_PKCS7(out, p7);
} else {
if(to) BIO_printf(out, "To: %s\n", to);
if(from) BIO_printf(out, "From: %s\n", from);
if(subject) BIO_printf(out, "Subject: %s\n", subject);
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if(outformat == FORMAT_SMIME)
SMIME_write_PKCS7(out, p7, in, flags);
else if(outformat == FORMAT_PEM)
PEM_write_bio_PKCS7(out,p7);
else if(outformat == FORMAT_ASN1)
i2d_PKCS7_bio(out,p7);
else {
BIO_printf(bio_err, "Bad output format for PKCS#7 file\n");
goto end;
}
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}
ret = 0;
end:
if (need_rand)
app_RAND_write_file(NULL, bio_err);
if(ret) ERR_print_errors(bio_err);
sk_X509_pop_free(encerts, X509_free);
sk_X509_pop_free(other, X509_free);
X509_STORE_free(store);
X509_free(cert);
X509_free(recip);
X509_free(signer);
EVP_PKEY_free(key);
PKCS7_free(p7);
BIO_free(in);
BIO_free(indata);
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BIO_free_all(out);
if(passin) OPENSSL_free(passin);
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return (ret);
}
static int save_certs(char *signerfile, STACK_OF(X509) *signers)
{
int i;
BIO *tmp;
if(!signerfile) return 1;
tmp = BIO_new_file(signerfile, "w");
if(!tmp) return 0;
for(i = 0; i < sk_X509_num(signers); i++)
PEM_write_bio_X509(tmp, sk_X509_value(signers, i));
BIO_free(tmp);
return 1;
}