lshd.c 6.12 KB
Newer Older
Niels Möller's avatar
Niels Möller committed
1 2 3
/* lshd.c
 *
 * main server program.
4 5
 *
 * $Id$ */
Niels Möller's avatar
Niels Möller committed
6

7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
/* lsh, an implementation of the ssh protocol
 *
 * Copyright (C) 1998 Niels Mller
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */
Niels Möller's avatar
Niels Möller committed
25 26

#include <errno.h>
Niels Möller's avatar
Niels Möller committed
27
#include <locale.h>
Niels Möller's avatar
Niels Möller committed
28 29
#include <stdio.h>
#include <string.h>
Niels Möller's avatar
Niels Möller committed
30 31

#include "getopt.h"
Niels Möller's avatar
Niels Möller committed
32

33 34 35 36
#include "alist.h"
#include "atoms.h"
#include "crypto.h"
#include "format.h"
Niels Möller's avatar
Niels Möller committed
37
#include "io.h"
38
#include "randomness.h"
Niels Möller's avatar
Niels Möller committed
39
#include "server.h"
40 41 42 43 44 45 46 47
#include "server_keyexchange.h"
#include "werror.h"
#include "xalloc.h"

#if 0
#include "crypto.h"
#include "publickey_crypto.h"
#endif
Niels Möller's avatar
Niels Möller committed
48

Niels Möller's avatar
Niels Möller committed
49 50
#define BLOCK_SIZE 32768

Niels Möller's avatar
Niels Möller committed
51 52 53 54 55 56 57 58 59 60
/* Global variable */
struct io_backend backend;

void usage() NORETURN;

void usage()
{
  exit(1);
}

Niels Möller's avatar
Niels Möller committed
61 62 63 64
struct signer *secret_key;
struct lsh_string *public_key;

/* A key generated by gnupg */
65
static void init_host_key(struct randomness *r)
Niels Möller's avatar
Niels Möller committed
66 67 68
{
  mpz_t p, q, g, y, a;
  mpz_t tmp;
69
  struct lsh_string *s;
Niels Möller's avatar
Niels Möller committed
70 71 72 73 74 75 76
  
  mpz_init_set_str(p,
		   "BC7797D55CF2449CA4B02396246AF5C75CA38C52B6F2E543"
		   "6754198B137B25B0A81DFE269D5CDFD0AEA290A32BA5B918"
		   "B58D64762D40EAA8D70F282B3AC4A7771171B1B1D1AE89F4"
		   "1CD091FE95A6F42A2340081F9E97A4B5F953DE223F10F878"
		   "4C0619A9979643E5325DF71C9C088F3BC82FA0A6C47B5C64"
77
		   "BC07A31B9CDB2B07", 16);
Niels Möller's avatar
Niels Möller committed
78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118
  mpz_init_set_str(q,
		   "867F7E6563B3FAF19B65C83E9B843150C5CC2201", 16);
  mpz_init_set_str(g,
		   "7FA83EAEDFD8679A4A80C869AD7E353F3B517569C2079C79"
		   "97EA6655764581B073F71AA15C07A789AEB213B106741AAB"
		   "CA81B8300B1F8510D3CD1C3D9D7D11640C1608E8E2E71527"
		   "68B8FDCB5544E29A020D14CC5C12E264C59E57E9F6832DA7"
		   "10B805CD9866C1110D60069D31D5A72D1A1ED96F2B11CFEF"
		   "7AB347F0632CB0C7", 16);
  mpz_init_set_str(y,
		   "2DA5B458DF3616097FA22DB6BDDD31A29E532054D4C208F7"
		   "EBF63EB2476E8E98E0885CFBC5669B56EC834E42058E8BCF"
		   "C259CA1BE981D7721306709499DE27E7B13F62359D9520D1"
		   "3D73C62E8E5C5F6B8E2C70217EC3B557FBCB98535BE3C6EE"
		   "0C71DEC1FE9C6791D3780DD8D593D5030969D303A5818B01"
		   "C4B855C07E8C4F64", 16);
  mpz_set_str(a,
	      "295190AEDBBD6EBD2F817F7D8CCC8B0095DCD82E", 16);

  mpz_init_set(tmp, g);
  mpz_powm(tmp, tmp, a, p);
  if (mpz_cmp(tmp, y))
    fatal("Test key invalid\n");

  mpz_clear(tmp);

  public_key = ssh_format("%a%n%n%n%n", ATOM_SSH_DSS, p, q, g, y);
  s = ssh_format("%n", a);

  secret_key = MAKE_SIGNER(make_dss_algorithm(r),
			   public_key->length, public_key->data,
			   s->length, s->data);

  lsh_free(s);
  mpz_clear(p);
  mpz_clear(q);
  mpz_clear(g);
  mpz_clear(y);
  mpz_clear(a);
}

119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159
struct simple_kexinit
{
  struct make_kexinit super;
  struct randomness *r;
};

static struct kexinit *do_make_kexinit(struct make_kexinit *c)
{
  struct simple_kexinit *closure = (struct simple_kexinit *) c;
  struct kexinit *res = xalloc(sizeof(struct kexinit));

  static int kex_algorithms[] = { ATOM_DIFFIE_HELLMAN_GROUP1_SHA1, 0 };
  static int server_hostkey_algorithms[] = { ATOM_SSH_DSS, 0 };
  static int crypto_algorithms[] = { ATOM_ARCFOUR, ATOM_NONE, 0 };
  static int mac_algorithms[] = { ATOM_HMAC_SHA1, 0 };
  static int compression_algorithms[] = { ATOM_NONE, 0 };
  
  RANDOM(closure->r, 16, res->cookie);
  res->kex_algorithms = kex_algorithms;
  res->server_hostkey_algorithms = server_hostkey_algorithms;
  res->parameters[KEX_ENCRYPTION_CLIENT_TO_SERVER] = crypto_algorithms;
  res->parameters[KEX_ENCRYPTION_SERVER_TO_CLIENT] = crypto_algorithms;
  res->parameters[KEX_MAC_CLIENT_TO_SERVER] = mac_algorithms;
  res->parameters[KEX_MAC_SERVER_TO_CLIENT] = mac_algorithms;
  res->parameters[KEX_COMPRESSION_CLIENT_TO_SERVER] = compression_algorithms;
  res->parameters[KEX_COMPRESSION_SERVER_TO_CLIENT] = compression_algorithms;
  res->first_kex_packet_follows = 0;

  return res;
}

struct make_kexinit *make_simple_kexinit(struct randomness *r)
{
  struct simple_kexinit *res = xalloc(sizeof(struct simple_kexinit));

  res->super.make = do_make_kexinit;
  res->r = r;

  return &res->super;
}

Niels Möller's avatar
Niels Möller committed
160 161
int main(int argc, char **argv)
{
162
  char *host = NULL;  /* Interface to bind */
Niels Möller's avatar
Niels Möller committed
163 164 165
  char *port = "ssh";
  int option;

166
  struct sockaddr_in local;
167 168 169 170 171 172 173

  struct randomness *r;
  struct diffie_hellman_method *dh;
  struct keyexchange_algorithm *kex;
  struct alist *algorithms;
  struct packet_handler *kexinit_handler;
  
Niels Möller's avatar
Niels Möller committed
174 175 176 177
  /* For filtering messages. Could perhaps also be used when converting
   * strings to and from UTF8. */
  setlocale(LC_CTYPE, "");
  
Niels Möller's avatar
Niels Möller committed
178
  while((option = getopt(argc, argv, "dp:qi:v")) != -1)
Niels Möller's avatar
Niels Möller committed
179 180 181 182 183 184 185 186 187 188 189
    switch(option)
      {
      case 'p':
	port = optarg;
	break;
      case 'q':
	quiet_flag = 1;
	break;
      case 'd':
	debug_flag = 1;
	break;
190 191 192
      case 'i':
	host = optarg;
	break;
Niels Möller's avatar
Niels Möller committed
193 194 195
      case 'v':
	verbose_flag = 1;
	break;
Niels Möller's avatar
Niels Möller committed
196 197 198 199 200 201 202
      default:
	usage();
      }

  if ( (argc - optind) != 0)
    usage();

203 204 205 206 207 208 209 210 211 212 213
  r = make_poor_random(&sha_algorithm, ssh_format("%z", "gazonk"));
  dh = make_dh1(r);
  init_host_key(r); /* Initializes public_key and secret_key */
  kex = make_dh_server(dh, public_key, secret_key);
  algorithms = make_alist(4,
			  ATOM_ARCFOUR, crypto_rc4_algorithm,
			  ATOM_HMAC_SHA1, make_hmac_algorithm(&sha_algorithm),
			  ATOM_DIFFIE_HELLMAN_GROUP1_SHA1, kex,
			  ATOM_SSH_DSS, make_dss_algorithm(r), -1);
  kexinit_handler = make_kexinit_handler(make_simple_kexinit(r), algorithms);
    
214
  if (!get_inaddr(&local, host, port, "tcp"))
Niels Möller's avatar
Niels Möller committed
215 216 217 218 219
    {
      fprintf(stderr, "No such host or service");
      exit(1);
    }

Niels Möller's avatar
Niels Möller committed
220
  if (!io_listen(&backend, &local, 
Niels Möller's avatar
Niels Möller committed
221
	    make_server_callback(&backend,
222 223 224
				 "lsh - a free ssh",
				 BLOCK_SIZE,
				 kexinit_handler)))
Niels Möller's avatar
Niels Möller committed
225 226 227 228
    {
      werror("lsh: Connection failed: %s\n", strerror(errno));
      return 1;
    }
Niels Möller's avatar
Niels Möller committed
229
  
Niels Möller's avatar
Niels Möller committed
230
  io_run(&backend);
Niels Möller's avatar
Niels Möller committed
231 232 233

  return 0;
}