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