client_common.c

   1 /*
   2  * Copyright (C) 1997-2006 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                 close(pcd->fd);
  55         free(pcd->user);
  56         free(pcd->config_file);
  57         free(pcd->key_file);
  58         free(pcd);
  59 }
  60
  61 int client_parse_config(int argc, char *argv[],
  62                 struct private_client_data **pcd_ptr)
  63 {
  64         char *home = para_homedir();
  65         struct stat statbuf;
  66         int ret;
  67         struct private_client_data *pcd =
  68                 para_calloc(sizeof(struct private_client_data));
  69
  70         pcd->fd = -1;
  71         client_cmdline_parser(argc, argv, &pcd->conf);
  72         ret = - E_CLIENT_SYNTAX;
  73         if (!pcd->conf.inputs_num)
  74                 goto out;
  75         pcd->user = pcd->conf.user_given?
  76                 para_strdup(pcd->conf.user_arg) : para_logname();
  77
  78         pcd->key_file = pcd->conf.key_file_given?
  79                 para_strdup(pcd->conf.key_file_arg) :
  80                 make_message("%s/.paraslash/key.%s", home, pcd->user);
  81
  82         pcd->config_file = pcd->conf.config_file_given?
  83                 para_strdup(pcd->conf.config_file_arg) :
  84                 make_message("%s/.paraslash/client.conf", home);
  85         ret = stat(pcd->config_file, &statbuf);
  86         if (ret && pcd->conf.config_file_given) {
  87                 ret = -E_NO_CONFIG;
  88                 goto out;
  89         }
  90         if (!ret)
  91                 client_cmdline_parser_configfile(pcd->config_file,
  92                         &pcd->conf, 0, 0, 0);
  93         ret = 1;
  94         *pcd_ptr = pcd;
  95         PARA_INFO_LOG(
  96                 "current loglevel: %d\n"
  97                 "using config_file: %s\n"
  98                 "using key_file: %s\n"
  99                 "connecting to %s:%d\n" ,
 100                 pcd->conf.loglevel_arg,
 101                 pcd->config_file,
 102                 pcd->key_file,
 103                 pcd->conf.hostname_arg, pcd->conf.server_port_arg
 104         );
 105 out:
 106         free(home);
 107         if (ret < 0)
 108                 client_close(pcd);
 109         return ret;
 110 }
 111
 112 void client_pre_select(struct sched *s, struct task *t)
 113 {
 114         struct private_client_data *pcd = t->private_data;
 115
 116         t->ret = 1;
 117         pcd->check_r = 0;
 118         pcd->check_w = 0;
 119         if (pcd->fd < 0)
 120                 return;
 121         switch (pcd->status) {
 122         case CL_CONNECTED:
 123         case CL_SENT_AUTH:
 124         case CL_SENT_CH_RESPONSE:
 125         case CL_SENT_COMMAND:
 126                 para_fd_set(pcd->fd, &s->rfds, &s->max_fileno);
 127                 pcd->check_r = 1;
 128                 return;
 129
 130         case CL_RECEIVED_WELCOME:
 131         case CL_RECEIVED_CHALLENGE:
 132         case CL_RECEIVED_PROCEED:
 133                 para_fd_set(pcd->fd, &s->wfds, &s->max_fileno);
 134                 pcd->check_w = 1;
 135                 return;
 136
 137         case CL_RECEIVING_SERVER_OUTPUT:
 138                 if (pcd->loaded < CLIENT_BUFSIZE - 1) {
 139                         para_fd_set(pcd->fd, &s->rfds, &s->max_fileno);
 140                         pcd->check_r = 1;
 141                 }
 142                 return;
 143         case CL_SENDING_STDIN:
 144                 if (*pcd->in_loaded) {
 145                         PARA_INFO_LOG("loaded: %zd\n", *pcd->in_loaded);
 146                         para_fd_set(pcd->fd, &s->wfds, &s->max_fileno);
 147                         pcd->check_w = 1;
 148                 } else {
 149                         if (*pcd->in_eof) {
 150                                 t->ret = -E_INPUT_EOF;
 151                                 s->timeout.tv_sec = 0;
 152                                 s->timeout.tv_usec = 1;
 153                         }
 154                 }
 155                 return;
 156         }
 157 }
 158
 159 static ssize_t client_recv_buffer(struct private_client_data *pcd)
 160 {
 161         ssize_t ret = recv_buffer(pcd->fd, pcd->buf + pcd->loaded,
 162                 CLIENT_BUFSIZE - pcd->loaded);
 163         if (!ret)
 164                 return -E_SERVER_EOF;
 165         if (ret > 0)
 166                 pcd->loaded += ret;
 167         return ret;
 168
 169 }
 170
 171 void client_post_select(struct sched *s, struct task *t)
 172 {
 173         struct private_client_data *pcd = t->private_data;
 174
 175 //      PARA_INFO_LOG("status %d\n", pcd->status);
 176         t->ret = 1;
 177         if (pcd->fd < 0)
 178                 return;
 179         if (!pcd->check_r && !pcd->check_w)
 180                 return;
 181         if (pcd->check_r && !FD_ISSET(pcd->fd, &s->rfds))
 182                 return;
 183         if (pcd->check_w && !FD_ISSET(pcd->fd, &s->wfds))
 184                 return;
 185         switch (pcd->status) {
 186         case CL_CONNECTED: /* receive welcome message */
 187                 t->ret = client_recv_buffer(pcd);
 188                 if (t->ret > 0)
 189                         pcd->status = CL_RECEIVED_WELCOME;
 190                 return;
 191         case CL_RECEIVED_WELCOME: /* send auth command */
 192                 sprintf(pcd->buf, "auth %s%s", pcd->conf.plain_given?
 193                         "" : "rc4 ", pcd->user);
 194                 PARA_INFO_LOG("--> %s\n", pcd->buf);
 195                 t->ret = send_buffer(pcd->fd, pcd->buf);
 196                 if (t->ret >= 0)
 197                         pcd->status = CL_SENT_AUTH;
 198                 return;
 199         case CL_SENT_AUTH: /* receive challenge number */
 200                 pcd->loaded = 0;
 201                 t->ret = client_recv_buffer(pcd);
 202                 if (t->ret < 0)
 203                         return;
 204                 if (t->ret != 64) {
 205                         t->ret = -E_INVALID_CHALLENGE;
 206                         PARA_ERROR_LOG("received the following: %s\n", pcd->buf);
 207                         return;
 208                 }
 209                 PARA_INFO_LOG("%s", "<-- [challenge]\n");
 210                 /* decrypt challenge number */
 211                 t->ret = para_decrypt_challenge(pcd->key_file, &pcd->challenge_nr,
 212                         (unsigned char *) pcd->buf, 64);
 213                 if (t->ret > 0)
 214                         pcd->status = CL_RECEIVED_CHALLENGE;
 215                 return;
 216         case CL_RECEIVED_CHALLENGE: /* send decrypted challenge */
 217                 PARA_INFO_LOG("--> %lu\n", pcd->challenge_nr);
 218                 t->ret = send_va_buffer(pcd->fd, "%s%lu", CHALLENGE_RESPONSE_MSG,
 219                         pcd->challenge_nr);
 220                 if (t->ret > 0)
 221                         pcd->status = CL_SENT_CH_RESPONSE;
 222                 return;
 223         case CL_SENT_CH_RESPONSE: /* read server response */
 224                 {
 225                 size_t bytes_received;
 226                 unsigned char rc4_buf[2 * RC4_KEY_LEN] = "";
 227                 pcd->loaded = 0;
 228                 t->ret = client_recv_buffer(pcd);
 229                 if (t->ret < 0)
 230                         return;
 231                 bytes_received = t->ret;
 232                 PARA_DEBUG_LOG("++++ server info ++++\n%s\n++++ end of server "
 233                         "info ++++\n", pcd->buf);
 234                 /* check if server has sent "Proceed" message */
 235                 t->ret = -E_CLIENT_AUTH;
 236                 if (!strstr(pcd->buf, PROCEED_MSG))
 237                         return;
 238                 t->ret = 1;
 239                 pcd->status = CL_RECEIVED_PROCEED;
 240                 if (bytes_received < PROCEED_MSG_LEN + 32)
 241                         return;
 242                 PARA_INFO_LOG("%s", "decrypting session key\n");
 243                 t->ret = para_decrypt_buffer(pcd->key_file, rc4_buf,
 244                         (unsigned char *)pcd->buf + PROCEED_MSG_LEN + 1,
 245                         bytes_received - PROCEED_MSG_LEN - 1);
 246                 if (t->ret < 0)
 247                         return;
 248                 RC4_set_key(&pcd->rc4_send_key, RC4_KEY_LEN, rc4_buf);
 249                 RC4_set_key(&pcd->rc4_recv_key, RC4_KEY_LEN, rc4_buf + RC4_KEY_LEN);
 250                 enable_crypt(pcd->fd, rc4_recv, rc4_send, pcd);
 251                 }
 252         case CL_RECEIVED_PROCEED: /* concat args and send command */
 253                 {
 254                 int i;
 255                 char *command = NULL;
 256                 for (i = 0; i < pcd->conf.inputs_num; i++) {
 257                         char *tmp = command;
 258                         command = make_message("%s\n%s", command?
 259                                 command : "", pcd->conf.inputs[i]);
 260                         free(tmp);
 261                 }
 262                 command = para_strcat(command, EOC_MSG "\n");
 263                 PARA_DEBUG_LOG("--> %s\n", command);
 264                 t->ret = send_buffer(pcd->fd, command);
 265                 free(command);
 266                 if (t->ret > 0)
 267                         pcd->status = CL_SENT_COMMAND;
 268                 return;
 269                 }
 270         case CL_SENT_COMMAND:
 271                 pcd->loaded = 0;
 272                 t->ret = client_recv_buffer(pcd);
 273                 if (t->ret < 0)
 274                         return;
 275                 t->ret = -E_HANDSHAKE_COMPLETE;
 276                 if (strstr(pcd->buf, AWAITING_DATA_MSG))
 277                         pcd->status = CL_SENDING_STDIN;
 278                 else
 279                         pcd->status = CL_RECEIVING_SERVER_OUTPUT;
 280                 return;
 281         case CL_SENDING_STDIN: /* FIXME: might block */
 282                 PARA_INFO_LOG("loaded: %zd\n", *pcd->in_loaded);
 283                 t->ret = send_bin_buffer(pcd->fd, pcd->inbuf, *pcd->in_loaded);
 284                 if (t->ret <= 0) {
 285                         if (!t->ret)
 286                                 t->ret = 1;
 287                         return;
 288                 }
 289                 *pcd->in_loaded = 0; /* FIXME: short writes */
 290                 return;
 291         case CL_RECEIVING_SERVER_OUTPUT:
 292                 t->ret = client_recv_buffer(pcd);
 293                 return;
 294         }
 295
 296 }
 297
 298 int client_open(struct private_client_data *pcd)
 299 {
 300         int ret;
 301         struct hostent *he;
 302         struct sockaddr_in their_addr;
 303
 304         /* get the host info */
 305         PARA_NOTICE_LOG("getting host info of %s\n",
 306                 pcd->conf.hostname_arg);
 307         ret = get_host_info(pcd->conf.hostname_arg, &he);
 308         if (ret < 0)
 309                 goto out;
 310         /* get new socket */
 311         ret = get_socket();
 312         if (ret < 0)
 313                 goto out;
 314         pcd->fd = ret;
 315         /* init their_addr */
 316         init_sockaddr(&their_addr, pcd->conf.server_port_arg, he);
 317         /* connect */
 318         PARA_NOTICE_LOG("connecting to %s\n", pcd->conf.hostname_arg);
 319         ret = para_connect(pcd->fd, &their_addr);
 320         if (ret < 0)
 321                 goto out;
 322         pcd->status = CL_CONNECTED;
 323         pcd->task.pre_select = client_pre_select;
 324         pcd->task.post_select = client_post_select;
 325         pcd->task.private_data = pcd;
 326         sprintf(pcd->task.status, "client");
 327         register_task(&pcd->task);
 328         ret = 1;
 329 out:
 330         return ret;
 331 }