client_common.c

   1 /*
   2  * Copyright (C) 1997-2007 Andre Noll <maan@systemlinux.org>
   3  *
   4  *     This program is free software; you can redistribute it and/or modify
   5  *     it under the terms of the GNU General Public License as published by
   6  *     the Free Software Foundation; either version 2 of the License, or
   7  *     (at your option) any later version.
   8  *
   9  *     This program is distributed in the hope that it will be useful,
  10  *     but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  *     GNU General Public License for more details.
  13  *
  14  *     You should have received a copy of the GNU General Public License
  15  *     along with this program; if not, write to the Free Software
  16  *     Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
  17  */
  18
  19 /** \file client_common.c common functions of para_client and para_audiod */
  20
  21 #include "para.h"
  22 #include "list.h"
  23 #include "sched.h"
  24 #include "client.cmdline.h"
  25 #include "crypt.h"
  26 #include "rc4.h"
  27 #include "net.h"
  28 #include "fd.h"
  29 #include "string.h"
  30 #include "client.cmdline.h"
  31 #include "client.h"
  32 #include "error.h"
  33
  34 void rc4_send(unsigned long len, const unsigned char *indata,
  35                 unsigned char *outdata, void *private_data)
  36 {
  37         struct private_client_data *pcd = private_data;
  38         RC4(&pcd->rc4_send_key, len, indata, outdata);
  39 }
  40
  41 void rc4_recv(unsigned long len, const unsigned char *indata,
  42                 unsigned char *outdata, void *private_data)
  43 {
  44         struct private_client_data *pcd = private_data;
  45         RC4(&pcd->rc4_recv_key, len, indata, outdata);
  46 }
  47
  48
  49 void client_close(struct private_client_data *pcd)
  50 {
  51         if (!pcd)
  52                 return;
  53         if (pcd->fd >= 0) {
  54                 disable_crypt(pcd->fd);
  55                 close(pcd->fd);
  56         }
  57         free(pcd->user);
  58         free(pcd->config_file);
  59         free(pcd->key_file);
  60         free(pcd);
  61 }
  62
  63 static int client_connect(struct private_client_data *pcd)
  64 {
  65         int ret;
  66         struct hostent *he;
  67         struct sockaddr_in their_addr;
  68
  69         pcd->fd = -1;
  70         ret = get_host_info(pcd->conf.hostname_arg, &he);
  71         if (ret < 0)
  72                 return ret;
  73         /* get new socket */
  74         ret = get_socket();
  75         if (ret < 0)
  76                 return ret;
  77         pcd->fd = ret;
  78         /* init their_addr */
  79         init_sockaddr(&their_addr, pcd->conf.server_port_arg, he);
  80         ret = para_connect(pcd->fd, &their_addr);
  81         if (ret < 0)
  82                 goto err_out;
  83         pcd->status = CL_CONNECTED;
  84         ret = mark_fd_nonblock(pcd->fd);
  85         if (ret < 0)
  86                 goto err_out;
  87         pcd->task.pre_select = client_pre_select;
  88         pcd->task.post_select = client_post_select;
  89         pcd->task.private_data = pcd;
  90         sprintf(pcd->task.status, "client");
  91         register_task(&pcd->task);
  92         return 1;
  93 err_out:
  94         close(pcd->fd);
  95         pcd->fd = -1;
  96         return ret;
  97 }
  98
  99 int client_open(int argc, char *argv[], struct private_client_data **pcd_ptr)
 100 {
 101         char *home = para_homedir();
 102         struct stat statbuf;
 103         int ret;
 104         struct private_client_data *pcd =
 105                 para_calloc(sizeof(struct private_client_data));
 106
 107         *pcd_ptr = pcd;
 108         pcd->fd = -1;
 109         ret = client_cmdline_parser(argc, argv, &pcd->conf);
 110         ret = -E_CLIENT_SYNTAX;
 111         if (!pcd->conf.inputs_num)
 112                 goto out;
 113         pcd->user = pcd->conf.user_given?
 114                 para_strdup(pcd->conf.user_arg) : para_logname();
 115
 116         pcd->key_file = pcd->conf.key_file_given?
 117                 para_strdup(pcd->conf.key_file_arg) :
 118                 make_message("%s/.paraslash/key.%s", home, pcd->user);
 119
 120         pcd->config_file = pcd->conf.config_file_given?
 121                 para_strdup(pcd->conf.config_file_arg) :
 122                 make_message("%s/.paraslash/client.conf", home);
 123         ret = stat(pcd->config_file, &statbuf);
 124         if (ret && pcd->conf.config_file_given) {
 125                 ret = -E_NO_CONFIG;
 126                 goto out;
 127         }
 128         if (!ret)
 129                 client_cmdline_parser_configfile(pcd->config_file,
 130                         &pcd->conf, 0, 0, 0);
 131         ret = 1;
 132         PARA_INFO_LOG("loglevel: %d\n", pcd->conf.loglevel_arg);
 133         PARA_INFO_LOG("config_file: %s\n", pcd->config_file);
 134         PARA_INFO_LOG("key_file: %s\n", pcd->key_file);
 135         PARA_NOTICE_LOG("connecting %s:%d\n", pcd->conf.hostname_arg,
 136                 pcd->conf.server_port_arg);
 137         ret = client_connect(pcd);
 138 out:
 139         free(home);
 140         if (ret < 0) {
 141                 PARA_ERROR_LOG("%s\n", PARA_STRERROR(-ret));
 142                 client_close(pcd);
 143         }
 144         return ret;
 145 }
 146
 147 void client_pre_select(struct sched *s, struct task *t)
 148 {
 149         struct private_client_data *pcd = t->private_data;
 150
 151         t->ret = 1;
 152         pcd->check_r = 0;
 153         pcd->check_w = 0;
 154         if (pcd->fd < 0)
 155                 return;
 156         switch (pcd->status) {
 157         case CL_CONNECTED:
 158         case CL_SENT_AUTH:
 159         case CL_SENT_CH_RESPONSE:
 160         case CL_SENT_COMMAND:
 161                 para_fd_set(pcd->fd, &s->rfds, &s->max_fileno);
 162                 pcd->check_r = 1;
 163                 return;
 164
 165         case CL_RECEIVED_WELCOME:
 166         case CL_RECEIVED_CHALLENGE:
 167         case CL_RECEIVED_PROCEED:
 168                 para_fd_set(pcd->fd, &s->wfds, &s->max_fileno);
 169                 pcd->check_w = 1;
 170                 return;
 171
 172         case CL_RECEIVING:
 173                 if (pcd->loaded < CLIENT_BUFSIZE - 1) {
 174                         para_fd_set(pcd->fd, &s->rfds, &s->max_fileno);
 175                         pcd->check_r = 1;
 176                 }
 177                 return;
 178         case CL_SENDING:
 179                 if (*pcd->in_loaded) {
 180                         PARA_INFO_LOG("loaded: %zd\n", *pcd->in_loaded);
 181                         para_fd_set(pcd->fd, &s->wfds, &s->max_fileno);
 182                         pcd->check_w = 1;
 183                 } else {
 184                         if (*pcd->in_eof) {
 185                                 t->ret = -E_INPUT_EOF;
 186                                 s->timeout.tv_sec = 0;
 187                                 s->timeout.tv_usec = 1;
 188                         }
 189                 }
 190                 return;
 191         }
 192 }
 193
 194 static ssize_t client_recv_buffer(struct private_client_data *pcd)
 195 {
 196         ssize_t ret = recv_buffer(pcd->fd, pcd->buf + pcd->loaded,
 197                 CLIENT_BUFSIZE - pcd->loaded);
 198         if (!ret)
 199                 return -E_SERVER_EOF;
 200         if (ret > 0)
 201                 pcd->loaded += ret;
 202         return ret;
 203
 204 }
 205
 206 void client_post_select(struct sched *s, struct task *t)
 207 {
 208         struct private_client_data *pcd = t->private_data;
 209
 210 //      PARA_INFO_LOG("status %d\n", pcd->status);
 211         t->ret = 1;
 212         if (pcd->fd < 0)
 213                 return;
 214         if (!pcd->check_r && !pcd->check_w)
 215                 return;
 216         if (pcd->check_r && !FD_ISSET(pcd->fd, &s->rfds))
 217                 return;
 218         if (pcd->check_w && !FD_ISSET(pcd->fd, &s->wfds))
 219                 return;
 220         switch (pcd->status) {
 221         case CL_CONNECTED: /* receive welcome message */
 222                 t->ret = client_recv_buffer(pcd);
 223                 if (t->ret > 0)
 224                         pcd->status = CL_RECEIVED_WELCOME;
 225                 return;
 226         case CL_RECEIVED_WELCOME: /* send auth command */
 227                 sprintf(pcd->buf, "auth %s%s", pcd->conf.plain_given?
 228                         "" : "rc4 ", pcd->user);
 229                 PARA_INFO_LOG("--> %s\n", pcd->buf);
 230                 t->ret = send_buffer(pcd->fd, pcd->buf);
 231                 if (t->ret >= 0)
 232                         pcd->status = CL_SENT_AUTH;
 233                 return;
 234         case CL_SENT_AUTH: /* receive challenge number */
 235                 pcd->loaded = 0;
 236                 t->ret = client_recv_buffer(pcd);
 237                 if (t->ret < 0)
 238                         return;
 239                 if (t->ret != 64) {
 240                         t->ret = -E_INVALID_CHALLENGE;
 241                         PARA_ERROR_LOG("received the following: %s\n", pcd->buf);
 242                         return;
 243                 }
 244                 PARA_INFO_LOG("%s", "<-- [challenge]\n");
 245                 /* decrypt challenge number */
 246                 t->ret = para_decrypt_challenge(pcd->key_file, &pcd->challenge_nr,
 247                         (unsigned char *) pcd->buf, 64);
 248                 if (t->ret > 0)
 249                         pcd->status = CL_RECEIVED_CHALLENGE;
 250                 return;
 251         case CL_RECEIVED_CHALLENGE: /* send decrypted challenge */
 252                 PARA_INFO_LOG("--> %lu\n", pcd->challenge_nr);
 253                 t->ret = send_va_buffer(pcd->fd, "%s%lu", CHALLENGE_RESPONSE_MSG,
 254                         pcd->challenge_nr);
 255                 if (t->ret > 0)
 256                         pcd->status = CL_SENT_CH_RESPONSE;
 257                 return;
 258         case CL_SENT_CH_RESPONSE: /* read server response */
 259                 {
 260                 size_t bytes_received;
 261                 unsigned char rc4_buf[2 * RC4_KEY_LEN] = "";
 262                 pcd->loaded = 0;
 263                 t->ret = client_recv_buffer(pcd);
 264                 if (t->ret < 0)
 265                         return;
 266                 bytes_received = t->ret;
 267                 PARA_DEBUG_LOG("++++ server info ++++\n%s\n++++ end of server "
 268                         "info ++++\n", pcd->buf);
 269                 /* check if server has sent "Proceed" message */
 270                 t->ret = -E_CLIENT_AUTH;
 271                 if (!strstr(pcd->buf, PROCEED_MSG))
 272                         return;
 273                 t->ret = 1;
 274                 pcd->status = CL_RECEIVED_PROCEED;
 275                 if (bytes_received < PROCEED_MSG_LEN + 32)
 276                         return;
 277                 PARA_INFO_LOG("%s", "decrypting session key\n");
 278                 t->ret = para_decrypt_buffer(pcd->key_file, rc4_buf,
 279                         (unsigned char *)pcd->buf + PROCEED_MSG_LEN + 1,
 280                         bytes_received - PROCEED_MSG_LEN - 1);
 281                 if (t->ret < 0)
 282                         return;
 283                 RC4_set_key(&pcd->rc4_send_key, RC4_KEY_LEN, rc4_buf);
 284                 RC4_set_key(&pcd->rc4_recv_key, RC4_KEY_LEN, rc4_buf + RC4_KEY_LEN);
 285                 enable_crypt(pcd->fd, rc4_recv, rc4_send, pcd);
 286                 }
 287         case CL_RECEIVED_PROCEED: /* concat args and send command */
 288                 {
 289                 int i;
 290                 char *command = NULL;
 291                 for (i = 0; i < pcd->conf.inputs_num; i++) {
 292                         char *tmp = command;
 293                         command = make_message("%s\n%s", command?
 294                                 command : "", pcd->conf.inputs[i]);
 295                         free(tmp);
 296                 }
 297                 command = para_strcat(command, EOC_MSG "\n");
 298                 PARA_DEBUG_LOG("--> %s\n", command);
 299                 t->ret = send_buffer(pcd->fd, command);
 300                 free(command);
 301                 if (t->ret > 0)
 302                         pcd->status = CL_SENT_COMMAND;
 303                 return;
 304                 }
 305         case CL_SENT_COMMAND:
 306                 pcd->loaded = 0;
 307                 t->ret = client_recv_buffer(pcd);
 308                 if (t->ret < 0)
 309                         return;
 310                 t->ret = -E_HANDSHAKE_COMPLETE;
 311                 if (strstr(pcd->buf, AWAITING_DATA_MSG))
 312                         pcd->status = CL_SENDING;
 313                 else
 314                         pcd->status = CL_RECEIVING;
 315                 return;
 316         case CL_SENDING: /* FIXME: might block */
 317                 PARA_INFO_LOG("loaded: %zd\n", *pcd->in_loaded);
 318                 t->ret = send_bin_buffer(pcd->fd, pcd->inbuf, *pcd->in_loaded);
 319                 if (t->ret < 0)
 320                         return;
 321                 *pcd->in_loaded = 0; /* FIXME: short writes */
 322                 return;
 323         case CL_RECEIVING:
 324                 t->ret = client_recv_buffer(pcd);
 325                 return;
 326         }
 327
 328 }