openssl/apps/cms.c

/*
 * Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
 * project.
 */
/* ====================================================================
 * Copyright (c) 2008 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.
 * ====================================================================
 */

/* CMS utility function */

#include <stdio.h>
#include <string.h>
#include "apps.h"

#ifndef OPENSSL_NO_CMS

# include <openssl/crypto.h>
# include <openssl/pem.h>
# include <openssl/err.h>
# include <openssl/x509_vfy.h>
# include <openssl/x509v3.h>
# include <openssl/cms.h>

static int save_certs(char *signerfile, STACK_OF(X509) *signers);
static int cms_cb(int ok, X509_STORE_CTX *ctx);
static void receipt_request_print(CMS_ContentInfo *cms);
static CMS_ReceiptRequest *make_receipt_request(STACK_OF(OPENSSL_STRING)
                                                *rr_to, int rr_allorfirst, STACK_OF(OPENSSL_STRING)
                                                *rr_from);
static int cms_set_pkey_param(EVP_PKEY_CTX *pctx,
                              STACK_OF(OPENSSL_STRING) *param);

# define SMIME_OP        0x10
# define SMIME_IP        0x20
# define SMIME_SIGNERS   0x40
# define SMIME_ENCRYPT           (1 | SMIME_OP)
# define SMIME_DECRYPT           (2 | SMIME_IP)
# define SMIME_SIGN              (3 | SMIME_OP | SMIME_SIGNERS)
# define SMIME_VERIFY            (4 | SMIME_IP)
# define SMIME_CMSOUT            (5 | SMIME_IP | SMIME_OP)
# define SMIME_RESIGN            (6 | SMIME_IP | SMIME_OP | SMIME_SIGNERS)
# define SMIME_DATAOUT           (7 | SMIME_IP)
# define SMIME_DATA_CREATE       (8 | SMIME_OP)
# define SMIME_DIGEST_VERIFY     (9 | SMIME_IP)
# define SMIME_DIGEST_CREATE     (10 | SMIME_OP)
# define SMIME_UNCOMPRESS        (11 | SMIME_IP)
# define SMIME_COMPRESS          (12 | SMIME_OP)
# define SMIME_ENCRYPTED_DECRYPT (13 | SMIME_IP)
# define SMIME_ENCRYPTED_ENCRYPT (14 | SMIME_OP)
# define SMIME_SIGN_RECEIPT      (15 | SMIME_IP | SMIME_OP)
# define SMIME_VERIFY_RECEIPT    (16 | SMIME_IP)

static int verify_err = 0;

typedef struct cms_key_param_st cms_key_param;

struct cms_key_param_st {
    int idx;
    STACK_OF(OPENSSL_STRING) *param;
    cms_key_param *next;
};

typedef enum OPTION_choice {
    OPT_ERR = -1, OPT_EOF = 0, OPT_HELP,
    OPT_INFORM, OPT_OUTFORM, OPT_IN, OPT_OUT, OPT_ENCRYPT,
    OPT_DECRYPT, OPT_SIGN, OPT_SIGN_RECEIPT, OPT_RESIGN,
    OPT_VERIFY, OPT_VERIFY_RETCODE, OPT_VERIFY_RECEIPT,
    OPT_CMSOUT, OPT_DATA_OUT, OPT_DATA_CREATE, OPT_DIGEST_VERIFY,
    OPT_DIGEST_CREATE, OPT_COMPRESS, OPT_UNCOMPRESS,
    OPT_ED_DECRYPT, OPT_ED_ENCRYPT, OPT_DEBUG_DECRYPT, OPT_TEXT,
    OPT_ASCIICRLF, OPT_NOINTERN, OPT_NOVERIFY, OPT_NOCERTS,
    OPT_NOATTR, OPT_NODETACH, OPT_NOSMIMECAP, OPT_BINARY, OPT_KEYID,
    OPT_NOSIGS, OPT_NO_CONTENT_VERIFY, OPT_NO_ATTR_VERIFY, OPT_INDEF,
    OPT_NOINDEF, OPT_NOOLDMIME, OPT_CRLFEOL, OPT_NOOUT, OPT_RR_PRINT,
    OPT_RR_ALL, OPT_RR_FIRST, OPT_RCTFORM, OPT_CERTFILE, OPT_CAFILE,
    OPT_CAPATH, OPT_NOCAPATH, OPT_NOCAFILE,OPT_CONTENT, OPT_PRINT,
    OPT_SECRETKEY, OPT_SECRETKEYID, OPT_PWRI_PASSWORD, OPT_ECONTENT_TYPE,
    OPT_RAND, OPT_PASSIN, OPT_TO, OPT_FROM, OPT_SUBJECT, OPT_SIGNER, OPT_RECIP,
    OPT_CERTSOUT, OPT_MD, OPT_INKEY, OPT_KEYFORM, OPT_KEYOPT, OPT_RR_FROM,
    OPT_RR_TO, OPT_AES128_WRAP, OPT_AES192_WRAP, OPT_AES256_WRAP,
    OPT_3DES_WRAP, OPT_ENGINE,
    OPT_V_ENUM,
    OPT_CIPHER
} OPTION_CHOICE;

OPTIONS cms_options[] = {
    {OPT_HELP_STR, 1, '-', "Usage: %s [options] cert.pem...\n"},
    {OPT_HELP_STR, 1, '-',
        "  cert.pem... recipient certs for encryption\n"},
    {OPT_HELP_STR, 1, '-', "Valid options are:\n"},
    {"help", OPT_HELP, '-', "Display this summary"},
    {"inform", OPT_INFORM, 'F', "Input format SMIME (default), PEM or DER"},
    {"outform", OPT_OUTFORM, 'F',
     "Output format SMIME (default), PEM or DER"},
    {"in", OPT_IN, '<', "Input file"},
    {"out", OPT_OUT, '>', "Output file"},
    {"encrypt", OPT_ENCRYPT, '-', "Encrypt message"},
    {"decrypt", OPT_DECRYPT, '-', "Decrypt encrypted message"},
    {"sign", OPT_SIGN, '-', "Sign message"},
    {"sign_receipt", OPT_SIGN_RECEIPT, '-'},
    {"resign", OPT_RESIGN, '-'},
    {"verify", OPT_VERIFY, '-', "Verify signed message"},
    {"verify_retcode", OPT_VERIFY_RETCODE, '-'},
    {"verify_receipt", OPT_VERIFY_RECEIPT, '<'},
    {"cmsout", OPT_CMSOUT, '-', "Output CMS structure"},
    {"data_out", OPT_DATA_OUT, '-'},
    {"data_create", OPT_DATA_CREATE, '-'},
    {"digest_verify", OPT_DIGEST_VERIFY, '-'},
    {"digest_create", OPT_DIGEST_CREATE, '-'},
    {"compress", OPT_COMPRESS, '-'},
    {"uncompress", OPT_UNCOMPRESS, '-'},
    {"EncryptedData_decrypt", OPT_ED_DECRYPT, '-'},
    {"EncryptedData_encrypt", OPT_ED_ENCRYPT, '-'},
    {"debug_decrypt", OPT_DEBUG_DECRYPT, '-'},
    {"text", OPT_TEXT, '-', "Include or delete text MIME headers"},
    {"asciicrlf", OPT_ASCIICRLF, '-'},
    {"nointern", OPT_NOINTERN, '-',
     "Don't search certificates in message for signer"},
    {"noverify", OPT_NOVERIFY, '-', "Don't verify signers certificate"},
    {"nocerts", OPT_NOCERTS, '-',
     "Don't include signers certificate when signing"},
    {"noattr", OPT_NOATTR, '-', "Don't include any signed attributes"},
    {"nodetach", OPT_NODETACH, '-', "Use opaque signing"},
    {"nosmimecap", OPT_NOSMIMECAP, '-'},
    {"binary", OPT_BINARY, '-', "Don't translate message to text"},
    {"keyid", OPT_KEYID, '-', "Use subject key identifier"},
    {"nosigs", OPT_NOSIGS, '-', "Don't verify message signature"},
    {"no_content_verify", OPT_NO_CONTENT_VERIFY, '-'},
    {"no_attr_verify", OPT_NO_ATTR_VERIFY, '-'},
    {"stream", OPT_INDEF, '-'},
    {"indef", OPT_INDEF, '-'},
    {"noindef", OPT_NOINDEF, '-'},
    {"nooldmime", OPT_NOOLDMIME, '-'},
    {"crlfeol", OPT_CRLFEOL, '-'},
    {"noout", OPT_NOOUT, '-'},
    {"receipt_request_print", OPT_RR_PRINT, '-'},
    {"receipt_request_all", OPT_RR_ALL, '-'},
    {"receipt_request_first", OPT_RR_FIRST, '-'},
    {"rctform", OPT_RCTFORM, 'F'},
    {"certfile", OPT_CERTFILE, '<', "Other certificates file"},
    {"CAfile", OPT_CAFILE, '<', "Trusted certificates file"},
    {"CApath", OPT_CAPATH, '/', "trusted certificates directory"},
    {"no-CAfile", OPT_NOCAFILE, '-',
     "Do not load the default certificates file"},
    {"no-CApath", OPT_NOCAPATH, '-',
     "Do not load certificates from the default certificates directory"},
    {"content", OPT_CONTENT, '<',
     "Supply or override content for detached signature"},
    {"print", OPT_PRINT, '-'},
    {"secretkey", OPT_SECRETKEY, 's'},
    {"secretkeyid", OPT_SECRETKEYID, 's'},
    {"pwri_password", OPT_PWRI_PASSWORD, 's'},
    {"econtent_type", OPT_ECONTENT_TYPE, 's'},
    {"rand", OPT_RAND, 's',
     "Load the file(s) into the random number generator"},
    {"passin", OPT_PASSIN, 's', "Input file pass phrase source"},
    {"to", OPT_TO, 's', "To address"},
    {"from", OPT_FROM, 's', "From address"},
    {"subject", OPT_SUBJECT, 's', "Subject"},
    {"signer", OPT_SIGNER, 's', "Signer certificate file"},
    {"recip", OPT_RECIP, '<', "Recipient cert file for decryption"},
    {"certsout", OPT_CERTSOUT, '>', "Certificate output file"},
    {"md", OPT_MD, 's'},
    {"inkey", OPT_INKEY, 's',
     "Input private key (if not signer or recipient)"},
    {"keyform", OPT_KEYFORM, 'f', "Input private key format (PEM or ENGINE)"},
    {"keyopt", OPT_KEYOPT, 's', "Set public key parameters as n:v pairs"},
    {"receipt_request_from", OPT_RR_FROM, 's'},
    {"receipt_request_to", OPT_RR_TO, 's'},
    {"", OPT_CIPHER, '-', "Any supported cipher"},
    OPT_V_OPTIONS,
    {"aes128-wrap", OPT_AES128_WRAP, '-', "Use AES128 to wrap key"},
    {"aes192-wrap", OPT_AES192_WRAP, '-', "Use AES192 to wrap key"},
    {"aes256-wrap", OPT_AES256_WRAP, '-', "Use AES256 to wrap key"},
# ifndef OPENSSL_NO_DES
    {"des3-wrap", OPT_3DES_WRAP, '-', "Use 3DES-EDE to wrap key"},
# endif
# ifndef OPENSSL_NO_ENGINE
    {"engine", OPT_ENGINE, 's', "Use engine e, possibly a hardware device"},
# endif
    {NULL}
};

int cms_main(int argc, char **argv)
{
    ASN1_OBJECT *econtent_type = NULL;
    BIO *in = NULL, *out = NULL, *indata = NULL, *rctin = NULL;
    CMS_ContentInfo *cms = NULL, *rcms = NULL;
    CMS_ReceiptRequest *rr = NULL;
    ENGINE *e = NULL;
    EVP_PKEY *key = NULL;
    const EVP_CIPHER *cipher = NULL, *wrap_cipher = NULL;
    const EVP_MD *sign_md = NULL;
    STACK_OF(OPENSSL_STRING) *rr_to = NULL, *rr_from = NULL;
    STACK_OF(OPENSSL_STRING) *sksigners = NULL, *skkeys = NULL;
    STACK_OF(X509) *encerts = NULL, *other = NULL;
    X509 *cert = NULL, *recip = NULL, *signer = NULL;
    X509_STORE *store = NULL;
    X509_VERIFY_PARAM *vpm = NULL;
    char *certfile = NULL, *keyfile = NULL, *contfile = NULL;
    char *CAfile = NULL, *CApath = NULL, *certsoutfile = NULL;
    int noCAfile = 0, noCApath = 0;
    char *infile = NULL, *outfile = NULL, *rctfile = NULL, *inrand = NULL;
    char *passinarg = NULL, *passin = NULL, *signerfile = NULL, *recipfile =
        NULL;
    char *to = NULL, *from = NULL, *subject = NULL, *prog;
    cms_key_param *key_first = NULL, *key_param = NULL;
    int flags = CMS_DETACHED, noout = 0, print = 0, keyidx = -1, vpmtouched =
        0;
    int informat = FORMAT_SMIME, outformat = FORMAT_SMIME;
    int need_rand = 0, operation = 0, ret = 1, rr_print = 0, rr_allorfirst =
        -1;
    int verify_retcode = 0, rctformat = FORMAT_SMIME, keyform = FORMAT_PEM;
    size_t secret_keylen = 0, secret_keyidlen = 0;
    unsigned char *pwri_pass = NULL, *pwri_tmp = NULL;
    unsigned char *secret_key = NULL, *secret_keyid = NULL;
    long ltmp;
    OPTION_CHOICE o;

    if ((vpm = X509_VERIFY_PARAM_new()) == NULL)
        return 1;

    prog = opt_init(argc, argv, cms_options);
    while ((o = opt_next()) != OPT_EOF) {
        switch (o) {
        case OPT_EOF:
        case OPT_ERR:
 opthelp:
            BIO_printf(bio_err, "%s: Use -help for summary.\n", prog);
            goto end;
        case OPT_HELP:
            opt_help(cms_options);
            ret = 0;
            goto end;
        case OPT_INFORM:
            if (!opt_format(opt_arg(), OPT_FMT_PEMDER, &informat))
                goto opthelp;
            break;
        case OPT_OUTFORM:
            if (!opt_format(opt_arg(), OPT_FMT_PEMDER, &outformat))
                goto opthelp;
            break;
        case OPT_OUT:
            outfile = opt_arg();
            break;
        case OPT_ENCRYPT:
            operation = SMIME_ENCRYPT;
            break;
        case OPT_DECRYPT:
            operation = SMIME_DECRYPT;
            break;
        case OPT_SIGN:
            operation = SMIME_SIGN;
            break;
        case OPT_SIGN_RECEIPT:
            operation = SMIME_SIGN_RECEIPT;
            break;
        case OPT_RESIGN:
            operation = SMIME_RESIGN;
            break;
        case OPT_VERIFY:
            operation = SMIME_VERIFY;
            break;
        case OPT_VERIFY_RETCODE:
            verify_retcode = 1;
            break;
        case OPT_VERIFY_RECEIPT:
            operation = SMIME_VERIFY_RECEIPT;
            rctfile = opt_arg();
            break;
        case OPT_CMSOUT:
            operation = SMIME_CMSOUT;
            break;
        case OPT_DATA_OUT:
            operation = SMIME_DATAOUT;
            break;
        case OPT_DATA_CREATE:
            operation = SMIME_DATA_CREATE;
            break;
        case OPT_DIGEST_VERIFY:
            operation = SMIME_DIGEST_VERIFY;
            break;
        case OPT_DIGEST_CREATE:
            operation = SMIME_DIGEST_CREATE;
            break;
        case OPT_COMPRESS:
            operation = SMIME_COMPRESS;
            break;
        case OPT_UNCOMPRESS:
            operation = SMIME_UNCOMPRESS;
            break;
        case OPT_ED_DECRYPT:
            operation = SMIME_ENCRYPTED_DECRYPT;
            break;
        case OPT_ED_ENCRYPT:
            operation = SMIME_ENCRYPTED_ENCRYPT;
            break;
        case OPT_DEBUG_DECRYPT:
            flags |= CMS_DEBUG_DECRYPT;
            break;
        case OPT_TEXT:
            flags |= CMS_TEXT;
            break;
        case OPT_ASCIICRLF:
            flags |= CMS_ASCIICRLF;
            break;
        case OPT_NOINTERN:
            flags |= CMS_NOINTERN;
            break;
        case OPT_NOVERIFY:
            flags |= CMS_NO_SIGNER_CERT_VERIFY;
            break;
        case OPT_NOCERTS:
            flags |= CMS_NOCERTS;
            break;
        case OPT_NOATTR:
            flags |= CMS_NOATTR;
            break;
        case OPT_NODETACH:
            flags &= ~CMS_DETACHED;
            break;
        case OPT_NOSMIMECAP:
            flags |= CMS_NOSMIMECAP;
            break;
        case OPT_BINARY:
            flags |= CMS_BINARY;
            break;
        case OPT_KEYID:
            flags |= CMS_USE_KEYID;
            break;
        case OPT_NOSIGS:
            flags |= CMS_NOSIGS;
            break;
        case OPT_NO_CONTENT_VERIFY:
            flags |= CMS_NO_CONTENT_VERIFY;
            break;
        case OPT_NO_ATTR_VERIFY:
            flags |= CMS_NO_ATTR_VERIFY;
            break;
        case OPT_INDEF:
            flags |= CMS_STREAM;
            break;
        case OPT_NOINDEF:
            flags &= ~CMS_STREAM;
            break;
        case OPT_NOOLDMIME:
            flags |= CMS_NOOLDMIMETYPE;
            break;
        case OPT_CRLFEOL:
            flags |= CMS_CRLFEOL;
            break;
        case OPT_NOOUT:
            noout = 1;
            break;
        case OPT_RR_PRINT:
            rr_print = 1;
            break;
        case OPT_RR_ALL:
            rr_allorfirst = 0;
            break;
        case OPT_RR_FIRST:
            rr_allorfirst = 1;
            break;
        case OPT_RCTFORM:
            if (rctformat == FORMAT_SMIME)
                rcms = SMIME_read_CMS(rctin, NULL);
            else if (rctformat == FORMAT_PEM)
                rcms = PEM_read_bio_CMS(rctin, NULL, NULL, NULL);
            else if (rctformat == FORMAT_ASN1)
                if (!opt_format(opt_arg(),
                                OPT_FMT_PEMDER | OPT_FMT_SMIME, &rctformat))
                    goto opthelp;
            break;
        case OPT_CERTFILE:
            certfile = opt_arg();
            break;
        case OPT_CAFILE:
            CAfile = opt_arg();
            break;
        case OPT_CAPATH:
            CApath = opt_arg();
            break;
        case OPT_NOCAFILE:
            noCAfile = 1;
            break;
        case OPT_NOCAPATH:
            noCApath = 1;
            break;
        case OPT_IN:
            infile = opt_arg();
            break;
        case OPT_CONTENT:
            contfile = opt_arg();
            break;
        case OPT_RR_FROM:
            if (rr_from == NULL
                && (rr_from = sk_OPENSSL_STRING_new_null()) == NULL)
                goto end;
            sk_OPENSSL_STRING_push(rr_from, opt_arg());
            break;
        case OPT_RR_TO:
            if (rr_to == NULL
                && (rr_to = sk_OPENSSL_STRING_new_null()) == NULL)
                goto end;
            sk_OPENSSL_STRING_push(rr_to, opt_arg());
            break;
        case OPT_PRINT:
            noout = print = 1;
            break;
        case OPT_SECRETKEY:
            secret_key = OPENSSL_hexstr2buf(opt_arg(), &ltmp);
            if (secret_key == NULL) {
                BIO_printf(bio_err, "Invalid key %s\n", opt_arg());
                goto end;
            }
            secret_keylen = (size_t)ltmp;
            break;
        case OPT_SECRETKEYID:
            secret_keyid = OPENSSL_hexstr2buf(opt_arg(), &ltmp);
            if (secret_keyid == NULL) {
                BIO_printf(bio_err, "Invalid id %s\n", opt_arg());
                goto opthelp;
            }
            secret_keyidlen = (size_t)ltmp;
            break;
        case OPT_PWRI_PASSWORD:
            pwri_pass = (unsigned char *)opt_arg();
            break;
        case OPT_ECONTENT_TYPE:
            econtent_type = OBJ_txt2obj(opt_arg(), 0);
            if (econtent_type == NULL) {
                BIO_printf(bio_err, "Invalid OID %s\n", opt_arg());
                goto opthelp;
            }
            break;
        case OPT_RAND:
            inrand = opt_arg();
            need_rand = 1;
            break;
        case OPT_ENGINE:
            e = setup_engine(opt_arg(), 0);
            break;
        case OPT_PASSIN:
            passinarg = opt_arg();
            break;
        case OPT_TO:
            to = opt_arg();
            break;
        case OPT_FROM:
            from = opt_arg();
            break;
        case OPT_SUBJECT:
            subject = opt_arg();
            break;
        case OPT_CERTSOUT:
            certsoutfile = opt_arg();
            break;
        case OPT_MD:
            if (!opt_md(opt_arg(), &sign_md))
                goto end;
            break;
        case OPT_SIGNER:
            /* If previous -signer argument add signer to list */
            if (signerfile) {
                if (sksigners == NULL
                    && (sksigners = sk_OPENSSL_STRING_new_null()) == NULL)
                    goto end;
                sk_OPENSSL_STRING_push(sksigners, signerfile);
                if (keyfile == NULL)
                    keyfile = signerfile;
                if (skkeys == NULL
                    && (skkeys = sk_OPENSSL_STRING_new_null()) == NULL)
                    goto end;
                sk_OPENSSL_STRING_push(skkeys, keyfile);
                keyfile = NULL;
            }
            signerfile = opt_arg();
            break;
        case OPT_INKEY:
            /* If previous -inkey arument add signer to list */
            if (keyfile) {
                if (signerfile == NULL) {
                    BIO_puts(bio_err, "Illegal -inkey without -signer\n");
                    goto end;
                }
                if (sksigners == NULL
                    && (sksigners = sk_OPENSSL_STRING_new_null()) == NULL)
                    goto end;
                sk_OPENSSL_STRING_push(sksigners, signerfile);
                signerfile = NULL;
                if (skkeys == NULL
                    && (skkeys = sk_OPENSSL_STRING_new_null()) == NULL)
                    goto end;
                sk_OPENSSL_STRING_push(skkeys, keyfile);
            }
            keyfile = opt_arg();
            break;
        case OPT_KEYFORM:
            if (!opt_format(opt_arg(), OPT_FMT_ANY, &keyform))
                goto opthelp;
            break;
        case OPT_RECIP:
            if (operation == SMIME_ENCRYPT) {
                if (encerts == NULL && (encerts = sk_X509_new_null()) == NULL)
                    goto end;
                cert = load_cert(opt_arg(), FORMAT_PEM,