/*

 * Copyright 1995-2020 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

 */

#include <openssl/opensslconf.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <time.h>

#include "apps.h"

#include "progs.h"

#include <openssl/bio.h>

#include <openssl/err.h>

#include <openssl/dsa.h>

#include <openssl/evp.h>

#include <openssl/x509.h>

#include <openssl/pem.h>

#include <openssl/bn.h>

typedef enum OPTION_choice {

    OPT_ERR = -1, OPT_EOF = 0, OPT_HELP,

    OPT_INFORM, OPT_OUTFORM, OPT_IN, OPT_OUT, OPT_ENGINE,

    /* Do not change the order here; see case statements below */

    OPT_PVK_NONE, OPT_PVK_WEAK, OPT_PVK_STRONG,

    OPT_NOOUT, OPT_TEXT, OPT_MODULUS, OPT_PUBIN,

    OPT_PUBOUT, OPT_CIPHER, OPT_PASSIN, OPT_PASSOUT

} OPTION_CHOICE;

const OPTIONS dsa_options[] = {

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

    {"inform", OPT_INFORM, 'f', "Input format, DER PEM PVK"},

    {"outform", OPT_OUTFORM, 'f', "Output format, DER PEM PVK"},

    {"in", OPT_IN, 's', "Input key"},

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

    {"noout", OPT_NOOUT, '-', "Don't print key out"},

    {"text", OPT_TEXT, '-', "Print the key in text"},

    {"modulus", OPT_MODULUS, '-', "Print the DSA public value"},

    {"pubin", OPT_PUBIN, '-', "Expect a public key in input file"},

    {"pubout", OPT_PUBOUT, '-', "Output public key, not private"},

    {"passin", OPT_PASSIN, 's', "Input file pass phrase source"},

    {"passout", OPT_PASSOUT, 's', "Output file pass phrase source"},

    {"", OPT_CIPHER, '-', "Any supported cipher"},

#ifndef OPENSSL_NO_RC4

    {"pvk-strong", OPT_PVK_STRONG, '-', "Enable 'Strong' PVK encoding level (default)"},

    {"pvk-weak", OPT_PVK_WEAK, '-', "Enable 'Weak' PVK encoding level"},

    {"pvk-none", OPT_PVK_NONE, '-', "Don't enforce PVK encoding"},

#endif

#ifndef OPENSSL_NO_ENGINE

    {"engine", OPT_ENGINE, 's', "Use engine e, possibly a hardware device"},

#endif

    {NULL}

};

int dsa_main(int argc, char **argv)

{

    BIO *out = NULL;

    DSA *dsa = NULL;

    ENGINE *e = NULL;

    const EVP_CIPHER *enc = NULL;

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

    char *passin = NULL, *passout = NULL, *passinarg = NULL, *passoutarg = NULL;

    OPTION_CHOICE o;

    int informat = FORMAT_PEM, outformat = FORMAT_PEM, text = 0, noout = 0;

    int i, modulus = 0, pubin = 0, pubout = 0, ret = 1;

#ifndef OPENSSL_NO_RC4

    int pvk_encr = 2;

#endif

    int private = 0;

    prog = opt_init(argc, argv, dsa_options);

    while ((o = opt_next()) != OPT_EOF) {

        switch (o) {

        case OPT_EOF:

        case OPT_ERR:

 opthelp:

            ret = 0;

            BIO_printf(bio_err, "%s: Use -help for summary.\n", prog);

            goto end;

        case OPT_HELP:

            opt_help(dsa_options);

            ret = 0;

            goto end;

        case OPT_INFORM:

            if (!opt_format(opt_arg(), OPT_FMT_ANY, &informat))

                goto opthelp;

            break;

        case OPT_IN:

            infile = opt_arg();

            break;

        case OPT_OUTFORM:

            if (!opt_format(opt_arg(), OPT_FMT_ANY, &outformat))

                goto opthelp;

            break;

        case OPT_OUT:

            outfile = opt_arg();

            break;

        case OPT_ENGINE:

            e = setup_engine(opt_arg(), 0);

            break;

        case OPT_PASSIN:

            passinarg = opt_arg();

            break;

        case OPT_PASSOUT:

            passoutarg = opt_arg();

            break;

        case OPT_PVK_STRONG:    /* pvk_encr:= 2 */

        case OPT_PVK_WEAK:      /* pvk_encr:= 1 */

        case OPT_PVK_NONE:      /* pvk_encr:= 0 */

#ifndef OPENSSL_NO_RC4

            pvk_encr = (o - OPT_PVK_NONE);

#endif

            break;

        case OPT_NOOUT:

            noout = 1;

            break;

        case OPT_TEXT:

            text = 1;

            break;

        case OPT_MODULUS:

            modulus = 1;

            break;

        case OPT_PUBIN:

            pubin = 1;

            break;

        case OPT_PUBOUT:

            pubout = 1;

            break;

        case OPT_CIPHER:

            if (!opt_cipher(opt_unknown(), &enc))

                goto end;

            break;

        }

    }

    argc = opt_num_rest();

    if (argc != 0)

        goto opthelp;

    private = pubin || pubout ? 0 : 1;

    if (text && !pubin)

        private = 1;

    if (!app_passwd(passinarg, passoutarg, &passin, &passout)) {

        BIO_printf(bio_err, "Error getting passwords\n");

        goto end;

    }

    BIO_printf(bio_err, "read DSA key\n");

    {

        EVP_PKEY *pkey;

        if (pubin)

            pkey = load_pubkey(infile, informat, 1, passin, e, "Public Key");

        else

            pkey = load_key(infile, informat, 1, passin, e, "Private Key");

        if (pkey != NULL) {

            dsa = EVP_PKEY_get1_DSA(pkey);

            EVP_PKEY_free(pkey);

        }

    }

    if (dsa == NULL) {

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

        ERR_print_errors(bio_err);

        goto end;

    }

    out = bio_open_owner(outfile, outformat, private);

    if (out == NULL)

        goto end;

    if (text) {

        assert(pubin || private);

        if (!DSA_print(out, dsa, 0)) {

            perror(outfile);

            ERR_print_errors(bio_err);

            goto end;

        }

    }

    if (modulus) {

        const BIGNUM *pub_key = NULL;

        DSA_get0_key(dsa, &pub_key, NULL);

        BIO_printf(out, "Public Key=");

        BN_print(out, pub_key);

        BIO_printf(out, "\n");

    }

    if (noout) {

        ret = 0;

        goto end;

    }

    BIO_printf(bio_err, "writing DSA key\n");

    if (outformat == FORMAT_ASN1) {

        if (pubin || pubout) {

            i = i2d_DSA_PUBKEY_bio(out, dsa);

        } else {

            assert(private);

            i = i2d_DSAPrivateKey_bio(out, dsa);

        }

    } else if (outformat == FORMAT_PEM) {

        if (pubin || pubout) {

            i = PEM_write_bio_DSA_PUBKEY(out, dsa);

        } else {

            assert(private);

            i = PEM_write_bio_DSAPrivateKey(out, dsa, enc,

                                            NULL, 0, NULL, passout);

        }

#ifndef OPENSSL_NO_RSA

    } else if (outformat == FORMAT_MSBLOB || outformat == FORMAT_PVK) {

        EVP_PKEY *pk;

        pk = EVP_PKEY_new();

        if (pk == NULL)

           goto end;

        EVP_PKEY_set1_DSA(pk, dsa);

        if (outformat == FORMAT_PVK) {

            if (pubin) {

                BIO_printf(bio_err, "PVK form impossible with public key input\n");

                EVP_PKEY_free(pk);

                goto end;

            }

            assert(private);

# ifdef OPENSSL_NO_RC4

            BIO_printf(bio_err, "PVK format not supported\n");

            EVP_PKEY_free(pk);

            goto end;

# else

            i = i2b_PVK_bio(out, pk, pvk_encr, 0, passout);

# endif

        } else if (pubin || pubout) {

            i = i2b_PublicKey_bio(out, pk);

        } else {

            assert(private);

            i = i2b_PrivateKey_bio(out, pk);

        }

        EVP_PKEY_free(pk);

#endif

    } else {

        BIO_printf(bio_err, "bad output format specified for outfile\n");

        goto end;

    }

    if (i <= 0) {

        BIO_printf(bio_err, "unable to write private key\n");

        ERR_print_errors(bio_err);

        goto end;

    }

    ret = 0;

 end:

    BIO_free_all(out);

    DSA_free(dsa);

    release_engine(e);

    OPENSSL_free(passin);

    OPENSSL_free(passout);

    return ret;

}