/*

 * Copyright 1995-2018 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

 */

#include <stdio.h>

#include <string.h>

#include <sys/types.h>

#include "apps.h"

#include "progs.h"

#include <openssl/err.h>

#include <openssl/evp.h>

#include <openssl/x509.h>

#include <openssl/pkcs7.h>

#include <openssl/pem.h>

#include <openssl/objects.h>

static int add_certs_from_file(STACK_OF(X509) *stack, char *certfile);

typedef enum OPTION_choice {

    OPT_ERR = -1, OPT_EOF = 0, OPT_HELP,

    OPT_INFORM, OPT_OUTFORM, OPT_IN, OPT_OUT, OPT_NOCRL, OPT_CERTFILE

} OPTION_CHOICE;

const OPTIONS crl2pkcs7_options[] = {

    {"help", OPT_HELP, '-', "Display this summary"},

    {"inform", OPT_INFORM, 'F', "Input format - DER or PEM"},

    {"outform", OPT_OUTFORM, 'F', "Output format - DER or PEM"},

    {"in", OPT_IN, '<', "Input file"},

    {"out", OPT_OUT, '>', "Output file"},

    {"nocrl", OPT_NOCRL, '-', "No crl to load, just certs from '-certfile'"},

    {"certfile", OPT_CERTFILE, '<',

     "File of chain of certs to a trusted CA; can be repeated"},

    {NULL}

};

int crl2pkcs7_main(int argc, char **argv)

{

    BIO *in = NULL, *out = NULL;

    PKCS7 *p7 = NULL;

    PKCS7_SIGNED *p7s = NULL;

    STACK_OF(OPENSSL_STRING) *certflst = NULL;

    STACK_OF(X509) *cert_stack = NULL;

    STACK_OF(X509_CRL) *crl_stack = NULL;

    X509_CRL *crl = NULL;

    char *infile = NULL, *outfile = NULL, *prog, *certfile;

    int i = 0, informat = FORMAT_PEM, outformat = FORMAT_PEM, ret = 1, nocrl =

        0;

    OPTION_CHOICE o;

    prog = opt_init(argc, argv, crl2pkcs7_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(crl2pkcs7_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_IN:

            infile = opt_arg();

            break;

        case OPT_OUT:

            outfile = opt_arg();

            break;

        case OPT_NOCRL:

            nocrl = 1;

            break;

        case OPT_CERTFILE:

            if ((certflst == NULL)

                && (certflst = sk_OPENSSL_STRING_new_null()) == NULL)

                goto end;

            if (!sk_OPENSSL_STRING_push(certflst, opt_arg()))

                goto end;

            break;

        }

    }

    argc = opt_num_rest();

    if (argc != 0)

        goto opthelp;

    if (!nocrl) {

        in = bio_open_default(infile, 'r', informat);

        if (in == NULL)

            goto end;

        if (informat == FORMAT_ASN1)

            crl = d2i_X509_CRL_bio(in, NULL);

        else if (informat == FORMAT_PEM)

            crl = PEM_read_bio_X509_CRL(in, NULL, NULL, NULL);

        if (crl == NULL) {

            BIO_printf(bio_err, "unable to load CRL\n");

            ERR_print_errors(bio_err);

            goto end;

        }

    }

    if ((p7 = PKCS7_new()) == NULL)

        goto end;

    if ((p7s = PKCS7_SIGNED_new()) == NULL)

        goto end;

    p7->type = OBJ_nid2obj(NID_pkcs7_signed);

    p7->d.sign = p7s;

    p7s->contents->type = OBJ_nid2obj(NID_pkcs7_data);

    if (!ASN1_INTEGER_set(p7s->version, 1))

        goto end;

    if ((crl_stack = sk_X509_CRL_new_null()) == NULL)

        goto end;

    p7s->crl = crl_stack;

    if (crl != NULL) {

        sk_X509_CRL_push(crl_stack, crl);

        crl = NULL;             /* now part of p7 for OPENSSL_freeing */

    }

    if ((cert_stack = sk_X509_new_null()) == NULL)

        goto end;

    p7s->cert = cert_stack;

    if (certflst != NULL)

        for (i = 0; i < sk_OPENSSL_STRING_num(certflst); i++) {

            certfile = sk_OPENSSL_STRING_value(certflst, i);

            if (add_certs_from_file(cert_stack, certfile) < 0) {

                BIO_printf(bio_err, "error loading certificates\n");

                ERR_print_errors(bio_err);

                goto end;

            }

        }

    out = bio_open_default(outfile, 'w', outformat);

    if (out == NULL)

        goto end;

    if (outformat == FORMAT_ASN1)

        i = i2d_PKCS7_bio(out, p7);

    else if (outformat == FORMAT_PEM)

        i = PEM_write_bio_PKCS7(out, p7);

    if (!i) {

        BIO_printf(bio_err, "unable to write pkcs7 object\n");

        ERR_print_errors(bio_err);

        goto end;

    }

    ret = 0;

 end:

    sk_OPENSSL_STRING_free(certflst);

    BIO_free(in);

    BIO_free_all(out);

    PKCS7_free(p7);

    X509_CRL_free(crl);

    return ret;

}

/*-

 *----------------------------------------------------------------------

 * int add_certs_from_file

 *

 *      Read a list of certificates to be checked from a file.

 *

 * Results:

 *      number of certs added if successful, -1 if not.

 *----------------------------------------------------------------------

 */

static int add_certs_from_file(STACK_OF(X509) *stack, char *certfile)

{

    BIO *in = NULL;

    int count = 0;

    int ret = -1;

    STACK_OF(X509_INFO) *sk = NULL;

    X509_INFO *xi;

    in = BIO_new_file(certfile, "r");

    if (in == NULL) {

        BIO_printf(bio_err, "error opening the file, %s\n", certfile);

        goto end;

    }

    /* This loads from a file, a stack of x509/crl/pkey sets */

    sk = PEM_X509_INFO_read_bio(in, NULL, NULL, NULL);

    if (sk == NULL) {

        BIO_printf(bio_err, "error reading the file, %s\n", certfile);

        goto end;

    }

    /* scan over it and pull out the CRL's */

    while (sk_X509_INFO_num(sk)) {

        xi = sk_X509_INFO_shift(sk);

        if (xi->x509 != NULL) {

            sk_X509_push(stack, xi->x509);

            xi->x509 = NULL;

            count++;

        }

        X509_INFO_free(xi);

    }

    ret = count;

 end:

    /* never need to OPENSSL_free x */

    BIO_free(in);

    sk_X509_INFO_free(sk);

    return ret;

}