/*

 * Copyright 2006-2018 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 "apps.h"

#include "progs.h"

#include <openssl/pem.h>

#include <openssl/err.h>

#include <openssl/evp.h>

#ifndef OPENSSL_NO_ENGINE

# include <openssl/engine.h>

#endif

static int init_keygen_file(EVP_PKEY_CTX **pctx, const char *file, ENGINE *e);

static int genpkey_cb(EVP_PKEY_CTX *ctx);

typedef enum OPTION_choice {

    OPT_ERR = -1, OPT_EOF = 0, OPT_HELP,

    OPT_ENGINE, OPT_OUTFORM, OPT_OUT, OPT_PASS, OPT_PARAMFILE,

    OPT_ALGORITHM, OPT_PKEYOPT, OPT_GENPARAM, OPT_TEXT, OPT_CIPHER

} OPTION_CHOICE;

const OPTIONS genpkey_options[] = {

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

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

    {"outform", OPT_OUTFORM, 'F', "output format (DER or PEM)"},

    {"pass", OPT_PASS, 's', "Output file pass phrase source"},

    {"paramfile", OPT_PARAMFILE, '<', "Parameters file"},

    {"algorithm", OPT_ALGORITHM, 's', "The public key algorithm"},

    {"pkeyopt", OPT_PKEYOPT, 's',

     "Set the public key algorithm option as opt:value"},

    {"genparam", OPT_GENPARAM, '-', "Generate parameters, not key"},

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

    {"", OPT_CIPHER, '-', "Cipher to use to encrypt the key"},

#ifndef OPENSSL_NO_ENGINE

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

#endif

    /* This is deliberately last. */

    {OPT_HELP_STR, 1, 1,

     "Order of options may be important!  See the documentation.\n"},

    {NULL}

};

int genpkey_main(int argc, char **argv)

{

    BIO *in = NULL, *out = NULL;

    ENGINE *e = NULL;

    EVP_PKEY *pkey = NULL;

    EVP_PKEY_CTX *ctx = NULL;

    char *outfile = NULL, *passarg = NULL, *pass = NULL, *prog;

    const EVP_CIPHER *cipher = NULL;

    OPTION_CHOICE o;

    int outformat = FORMAT_PEM, text = 0, ret = 1, rv, do_param = 0;

    int private = 0;

    prog = opt_init(argc, argv, genpkey_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:

            ret = 0;

            opt_help(genpkey_options);

            goto end;

        case OPT_OUTFORM:

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

                goto opthelp;

            break;

        case OPT_OUT:

            outfile = opt_arg();

            break;

        case OPT_PASS:

            passarg = opt_arg();

            break;

        case OPT_ENGINE:

            e = setup_engine(opt_arg(), 0);

            break;

        case OPT_PARAMFILE:

            if (do_param == 1)

                goto opthelp;

            if (!init_keygen_file(&ctx, opt_arg(), e))

                goto end;

            break;

        case OPT_ALGORITHM:

            if (!init_gen_str(&ctx, opt_arg(), e, do_param))

                goto end;

            break;

        case OPT_PKEYOPT:

            if (ctx == NULL) {

                BIO_printf(bio_err, "%s: No keytype specified.\n", prog);

                goto opthelp;

            }

            if (pkey_ctrl_string(ctx, opt_arg()) <= 0) {

                BIO_printf(bio_err,

                           "%s: Error setting %s parameter:\n",

                           prog, opt_arg());

                ERR_print_errors(bio_err);

                goto end;

            }

            break;

        case OPT_GENPARAM:

            if (ctx != NULL)

                goto opthelp;

            do_param = 1;

            break;

        case OPT_TEXT:

            text = 1;

            break;

        case OPT_CIPHER:

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

                || do_param == 1)

                goto opthelp;

            if (EVP_CIPHER_mode(cipher) == EVP_CIPH_GCM_MODE ||

                EVP_CIPHER_mode(cipher) == EVP_CIPH_CCM_MODE ||

                EVP_CIPHER_mode(cipher) == EVP_CIPH_XTS_MODE ||

                EVP_CIPHER_mode(cipher) == EVP_CIPH_OCB_MODE) {

                BIO_printf(bio_err, "%s: cipher mode not supported\n", prog);

                goto end;

            }

        }

    }

    argc = opt_num_rest();

    if (argc != 0)

        goto opthelp;

    private = do_param ? 0 : 1;

    if (ctx == NULL)

        goto opthelp;

    if (!app_passwd(passarg, NULL, &pass, NULL)) {

        BIO_puts(bio_err, "Error getting password\n");

        goto end;

    }

    out = bio_open_owner(outfile, outformat, private);

    if (out == NULL)

        goto end;

    EVP_PKEY_CTX_set_cb(ctx, genpkey_cb);

    EVP_PKEY_CTX_set_app_data(ctx, bio_err);

    if (do_param) {

        if (EVP_PKEY_paramgen(ctx, &pkey) <= 0) {

            BIO_puts(bio_err, "Error generating parameters\n");

            ERR_print_errors(bio_err);

            goto end;

        }

    } else {

        if (EVP_PKEY_keygen(ctx, &pkey) <= 0) {

            BIO_puts(bio_err, "Error generating key\n");

            ERR_print_errors(bio_err);

            goto end;

        }

    }

    if (do_param) {

        rv = PEM_write_bio_Parameters(out, pkey);

    } else if (outformat == FORMAT_PEM) {

        assert(private);

        rv = PEM_write_bio_PrivateKey(out, pkey, cipher, NULL, 0, NULL, pass);

    } else if (outformat == FORMAT_ASN1) {

        assert(private);

        rv = i2d_PrivateKey_bio(out, pkey);

    } else {

        BIO_printf(bio_err, "Bad format specified for key\n");

        goto end;

    }

    if (rv <= 0) {

        BIO_puts(bio_err, "Error writing key\n");

        ERR_print_errors(bio_err);

    }

    if (text) {

        if (do_param)

            rv = EVP_PKEY_print_params(out, pkey, 0, NULL);

        else

            rv = EVP_PKEY_print_private(out, pkey, 0, NULL);

        if (rv <= 0) {

            BIO_puts(bio_err, "Error printing key\n");

            ERR_print_errors(bio_err);

        }

    }

    ret = 0;

 end:

    EVP_PKEY_free(pkey);

    EVP_PKEY_CTX_free(ctx);

    BIO_free_all(out);

    BIO_free(in);

    release_engine(e);

    OPENSSL_free(pass);

    return ret;

}

static int init_keygen_file(EVP_PKEY_CTX **pctx, const char *file, ENGINE *e)

{

    BIO *pbio;

    EVP_PKEY *pkey = NULL;

    EVP_PKEY_CTX *ctx = NULL;

    if (*pctx) {

        BIO_puts(bio_err, "Parameters already set!\n");

        return 0;

    }

    pbio = BIO_new_file(file, "r");

    if (!pbio) {

        BIO_printf(bio_err, "Can't open parameter file %s\n", file);

        return 0;

    }

    pkey = PEM_read_bio_Parameters(pbio, NULL);

    BIO_free(pbio);

    if (!pkey) {

        BIO_printf(bio_err, "Error reading parameter file %s\n", file);

        return 0;

    }

    ctx = EVP_PKEY_CTX_new(pkey, e);

    if (ctx == NULL)

        goto err;

    if (EVP_PKEY_keygen_init(ctx) <= 0)

        goto err;

    EVP_PKEY_free(pkey);

    *pctx = ctx;

    return 1;

 err:

    BIO_puts(bio_err, "Error initializing context\n");

    ERR_print_errors(bio_err);

    EVP_PKEY_CTX_free(ctx);

    EVP_PKEY_free(pkey);

    return 0;

}

int init_gen_str(EVP_PKEY_CTX **pctx,

                 const char *algname, ENGINE *e, int do_param)

{

    EVP_PKEY_CTX *ctx = NULL;

    const EVP_PKEY_ASN1_METHOD *ameth;

    ENGINE *tmpeng = NULL;

    int pkey_id;

    if (*pctx) {

        BIO_puts(bio_err, "Algorithm already set!\n");

        return 0;

    }

    ameth = EVP_PKEY_asn1_find_str(&tmpeng, algname, -1);

#ifndef OPENSSL_NO_ENGINE

    if (!ameth && e)

        ameth = ENGINE_get_pkey_asn1_meth_str(e, algname, -1);

#endif

    if (!ameth) {

        BIO_printf(bio_err, "Algorithm %s not found\n", algname);

        return 0;

    }

    ERR_clear_error();

    EVP_PKEY_asn1_get0_info(&pkey_id, NULL, NULL, NULL, NULL, ameth);

#ifndef OPENSSL_NO_ENGINE

    ENGINE_finish(tmpeng);

#endif

    ctx = EVP_PKEY_CTX_new_id(pkey_id, e);

    if (!ctx)

        goto err;

    if (do_param) {

        if (EVP_PKEY_paramgen_init(ctx) <= 0)

            goto err;

    } else {

        if (EVP_PKEY_keygen_init(ctx) <= 0)

            goto err;

    }

    *pctx = ctx;

    return 1;

 err:

    BIO_printf(bio_err, "Error initializing %s context\n", algname);

    ERR_print_errors(bio_err);

    EVP_PKEY_CTX_free(ctx);

    return 0;

}

static int genpkey_cb(EVP_PKEY_CTX *ctx)

{

    char c = '*';

    BIO *b = EVP_PKEY_CTX_get_app_data(ctx);

    int p;

    p = EVP_PKEY_CTX_get_keygen_info(ctx, 0);

    if (p == 0)

        c = '.';

    if (p == 1)

        c = '+';

    if (p == 2)

        c = '*';

    if (p == 3)

        c = '\n';

    BIO_write(b, &c, 1);

    (void)BIO_flush(b);

    return 1;

}