/*
 * Copyright 1995-2016 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 <stdlib.h>
#include <string.h>
#include "apps.h"
#include <openssl/err.h>
#include <openssl/ssl.h>

typedef enum OPTION_choice {
    OPT_ERR = -1, OPT_EOF = 0, OPT_HELP,
    OPT_STDNAME,
    OPT_SSL3,
    OPT_TLS1,
    OPT_TLS1_1,
    OPT_TLS1_2,
    OPT_PSK,
    OPT_SRP,
    OPT_V, OPT_UPPER_V, OPT_S
} OPTION_CHOICE;

OPTIONS ciphers_options[] = {
    {"help", OPT_HELP, '-', "Display this summary"},
    {"v", OPT_V, '-', "Verbose listing of the SSL/TLS ciphers"},
    {"V", OPT_UPPER_V, '-', "Even more verbose"},
    {"s", OPT_S, '-', "Only supported ciphers"},
#ifndef OPENSSL_NO_SSL3
    {"ssl3", OPT_SSL3, '-', "SSL3 mode"},
#endif
#ifndef OPENSSL_NO_TLS1
    {"tls1", OPT_TLS1, '-', "TLS1 mode"},
#endif
#ifndef OPENSSL_NO_TLS1_1
    {"tls1_1", OPT_TLS1_1, '-', "TLS1.1 mode"},
#endif
#ifndef OPENSSL_NO_TLS1_2
    {"tls1_2", OPT_TLS1_2, '-', "TLS1.2 mode"},
#endif
#ifndef OPENSSL_NO_SSL_TRACE
    {"stdname", OPT_STDNAME, '-', "Show standard cipher names"},
#endif
#ifndef OPENSSL_NO_PSK
    {"psk", OPT_PSK, '-', "include ciphersuites requiring PSK"},
#endif
#ifndef OPENSSL_NO_SRP
    {"srp", OPT_SRP, '-', "include ciphersuites requiring SRP"},
#endif
    {NULL}
};

#ifndef OPENSSL_NO_PSK
static unsigned int dummy_psk(SSL *ssl, const char *hint, char *identity,
                              unsigned int max_identity_len,
                              unsigned char *psk,
                              unsigned int max_psk_len)
{
    return 0;
}
#endif
#ifndef OPENSSL_NO_SRP
static char *dummy_srp(SSL *ssl, void *arg)
{
    return "";
}
#endif

int ciphers_main(int argc, char **argv)
{
    SSL_CTX *ctx = NULL;
    SSL *ssl = NULL;
    STACK_OF(SSL_CIPHER) *sk = NULL;
    const SSL_METHOD *meth = TLS_server_method();
    int ret = 1, i, verbose = 0, Verbose = 0, use_supported = 0;
#ifndef OPENSSL_NO_SSL_TRACE
    int stdname = 0;
#endif
#ifndef OPENSSL_NO_PSK
    int psk = 0;
#endif
#ifndef OPENSSL_NO_SRP
    int srp = 0;
#endif
    const char *p;
    char *ciphers = NULL, *prog;
    char buf[512];
    OPTION_CHOICE o;
    int min_version = 0, max_version = 0;

    prog = opt_init(argc, argv, ciphers_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(ciphers_options);
            ret = 0;
            goto end;
        case OPT_V:
            verbose = 1;
            break;
        case OPT_UPPER_V:
            verbose = Verbose = 1;
            break;
        case OPT_S:
            use_supported = 1;
            break;
        case OPT_STDNAME:
#ifndef OPENSSL_NO_SSL_TRACE
            stdname = verbose = 1;
#endif
            break;
        case OPT_SSL3:
            min_version = SSL3_VERSION;
            max_version = SSL3_VERSION;
            break;
        case OPT_TLS1:
            min_version = TLS1_VERSION;
            max_version = TLS1_VERSION;
            break;
        case OPT_TLS1_1:
            min_version = TLS1_1_VERSION;
            max_version = TLS1_1_VERSION;
            break;
        case OPT_TLS1_2:
            min_version = TLS1_2_VERSION;
            max_version = TLS1_2_VERSION;
            break;
        case OPT_PSK:
#ifndef OPENSSL_NO_PSK
            psk = 1;
#endif
            break;
        case OPT_SRP:
#ifndef OPENSSL_NO_SRP
            srp = 1;
#endif
            break;
        }
    }
    argv = opt_rest();
    argc = opt_num_rest();

    if (argc == 1)
        ciphers = *argv;
    else if (argc != 0)
        goto opthelp;

    ctx = SSL_CTX_new(meth);
    if (ctx == NULL)
        goto err;
    if (SSL_CTX_set_min_proto_version(ctx, min_version) == 0)
        goto err;
    if (SSL_CTX_set_max_proto_version(ctx, max_version) == 0)
        goto err;

#ifndef OPENSSL_NO_PSK
    if (psk)
        SSL_CTX_set_psk_client_callback(ctx, dummy_psk);
#endif
#ifndef OPENSSL_NO_SRP
    if (srp)
        SSL_CTX_set_srp_client_pwd_callback(ctx, dummy_srp);
#endif
    if (ciphers != NULL) {
        if (!SSL_CTX_set_cipher_list(ctx, ciphers)) {
            BIO_printf(bio_err, "Error in cipher list\n");
            goto err;
        }
    }
    ssl = SSL_new(ctx);
    if (ssl == NULL)
        goto err;

    if (use_supported)
        sk = SSL_get1_supported_ciphers(ssl);
    else
        sk = SSL_get_ciphers(ssl);

    if (!verbose) {
        for (i = 0; i < sk_SSL_CIPHER_num(sk); i++) {
            const SSL_CIPHER *c = sk_SSL_CIPHER_value(sk, i);
            p = SSL_CIPHER_get_name(c);
            if (p == NULL)
                break;
            if (i != 0)
                BIO_printf(bio_out, ":");
            BIO_printf(bio_out, "%s", p);
        }
        BIO_printf(bio_out, "\n");
    } else {

        for (i = 0; i < sk_SSL_CIPHER_num(sk); i++) {
            const SSL_CIPHER *c;

            c = sk_SSL_CIPHER_value(sk, i);

            if (Verbose) {
                unsigned long id = SSL_CIPHER_get_id(c);
                int id0 = (int)(id >> 24);
                int id1 = (int)((id >> 16) & 0xffL);
                int id2 = (int)((id >> 8) & 0xffL);
                int id3 = (int)(id & 0xffL);

                if ((id & 0xff000000L) == 0x03000000L)
                    BIO_printf(bio_out, "          0x%02X,0x%02X - ", id2, id3); /* SSL3
                                                                                  * cipher */
                else
                    BIO_printf(bio_out, "0x%02X,0x%02X,0x%02X,0x%02X - ", id0, id1, id2, id3); /* whatever */
            }
#ifndef OPENSSL_NO_SSL_TRACE
            if (stdname) {
                const char *nm = SSL_CIPHER_standard_name(c);
                if (nm == NULL)
                    nm = "UNKNOWN";
                BIO_printf(bio_out, "%s - ", nm);
            }
#endif
            BIO_puts(bio_out, SSL_CIPHER_description(c, buf, sizeof buf));
        }
    }

    ret = 0;
    goto end;
 err:
    ERR_print_errors(bio_err);
 end:
    if (use_supported)
        sk_SSL_CIPHER_free(sk);
    SSL_CTX_free(ctx);
    SSL_free(ssl);
    return (ret);
}