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.h"
  31 #include "error.h"
  32
  33 void rc4_send(unsigned long len, const unsigned char *indata,
  34                 unsigned char *outdata, void *private_data)
  35 {
  36         struct private_client_data *pcd = private_data;
  37         RC4(&pcd->rc4_send_key, len, indata, outdata);
  38 }
  39
  40 void rc4_recv(unsigned long len, const unsigned char *indata,
  41                 unsigned char *outdata, void *private_data)
  42 {
  43         struct private_client_data *pcd = private_data;
  44         RC4(&pcd->rc4_recv_key, len, indata, outdata);
  45 }
  46
  47
  48 void client_close(struct private_client_data *pcd)
  49 {
  50         if (pcd)
  51                 return;
  52         if (pcd->fd >= 0)
  53                 close(pcd->fd);
  54         free(pcd->user);
  55         free(pcd->config_file);
  56         free(pcd->key_file);
  57         free(pcd);
  58 }
  59
  60 int client_parse_config(int argc, char *argv[],
  61                 struct private_client_data **pcd_ptr)
  62 {
  63         char *home = para_homedir();
  64         struct stat statbuf;
  65         int ret;
  66         struct private_client_data *pcd =
  67                 para_calloc(sizeof(struct private_client_data));
  68
  69         pcd->fd = -1;
  70         cmdline_parser(argc, argv, &pcd->conf);
  71         ret = - E_CLIENT_SYNTAX;
  72         if (!pcd->conf.inputs_num)
  73                 goto out;
  74         pcd->user = pcd->conf.user_given?
  75                 para_strdup(pcd->conf.user_arg) : para_logname();
  76
  77         pcd->key_file = pcd->conf.key_file_given?
  78                 para_strdup(pcd->conf.key_file_arg) :
  79                 make_message("%s/.paraslash/key.%s", home, pcd->user);
  80
  81         pcd->config_file = pcd->conf.config_file_given?
  82                 para_strdup(pcd->conf.config_file_arg) :
  83                 make_message("%s/.paraslash/client.conf", home);
  84         ret = stat(pcd->config_file, &statbuf);
  85         if (ret && pcd->conf.config_file_given) {
  86                 ret = -E_NO_CONFIG;
  87                 goto out;
  88         }
  89         if (!ret)
  90                 cmdline_parser_configfile(pcd->config_file, &pcd->conf, 0, 0, 0);
  91         ret = 1;
  92         *pcd_ptr = pcd;
  93         PARA_INFO_LOG(
  94                 "current loglevel: %d\n"
  95                 "using config_file: %s\n"
  96                 "using key_file: %s\n"
  97                 "connecting to %s:%d\n" ,
  98                 pcd->conf.loglevel_arg,
  99                 pcd->config_file,
 100                 pcd->key_file,
 101                 pcd->conf.hostname_arg, pcd->conf.server_port_arg
 102         );
 103 out:
 104         free(home);
 105         if (ret < 0)
 106                 client_close(pcd);
 107         return ret;
 108 }
 109
 110 void client_pre_select(struct sched *s, struct task *t)
 111 {
 112         struct private_client_data *pcd = t->private_data;
 113
 114         PARA_INFO_LOG("status %d\n", pcd->status);
 115         t->ret = 1;
 116         pcd->check_r = 0;
 117         pcd->check_w = 0;
 118         if (pcd->fd < 0)
 119                 return;
 120         switch (pcd->status) {
 121         case CL_CONNECTED:
 122         case CL_SENT_AUTH:
 123         case CL_SENT_CH_RESPONSE:
 124         case CL_SENT_COMMAND:
 125                 para_fd_set(pcd->fd, &s->rfds, &s->max_fileno);
 126                 pcd->check_r = 1;
 127                 return;
 128
 129         case CL_RECEIVED_WELCOME:
 130         case CL_RECEIVED_CHALLENGE:
 131         case CL_RECEIVED_PROCEED:
 132                 para_fd_set(pcd->fd, &s->wfds, &s->max_fileno);
 133                 pcd->check_w = 1;
 134                 return;
 135
 136         case CL_RECEIVING_SERVER_OUTPUT:
 137                 if (pcd->loaded < CLIENT_BUFSIZE - 1) {
 138                         para_fd_set(pcd->fd, &s->rfds, &s->max_fileno);
 139                         pcd->check_r = 1;
 140                 }
 141                 return;
 142         case CL_SENDING_STDIN:
 143                 if (*pcd->in_loaded) {
 144                         PARA_INFO_LOG("loaded: %zd\n", *pcd->in_loaded);
 145                         para_fd_set(pcd->fd, &s->wfds, &s->max_fileno);
 146                         pcd->check_w = 1;
 147                 } else {
 148                         if (*pcd->in_eof) {
 149                                 t->ret = -E_INPUT_EOF;
 150                                 s->timeout.tv_sec = 0;
 151                                 s->timeout.tv_usec = 1;
 152                         }
 153                 }
 154                 return;
 155         }
 156 }
 157
 158 static ssize_t client_recv_buffer(struct private_client_data *pcd)
 159 {
 160         ssize_t ret = recv_buffer(pcd->fd, pcd->buf + pcd->loaded,
 161                 CLIENT_BUFSIZE - pcd->loaded);
 162         if (!ret)
 163                 return -E_SERVER_EOF;
 164         if (ret > 0)
 165                 pcd->loaded += ret;
 166         return ret;
 167
 168 }
 169
 170 void client_post_select(struct sched *s, struct task *t)
 171 {
 172         struct private_client_data *pcd = t->private_data;
 173
 174         PARA_INFO_LOG("status %d\n", pcd->status);
 175         t->ret = 1;
 176         if (pcd->fd < 0)
 177                 return;
 178         if (!pcd->check_r && !pcd->check_w)
 179                 return;
 180         if (pcd->check_r && !FD_ISSET(pcd->fd, &s->rfds))
 181                 return;
 182         if (pcd->check_w && !FD_ISSET(pcd->fd, &s->wfds))
 183                 return;
 184         switch (pcd->status) {
 185         case CL_CONNECTED: /* receive welcome message */
 186                 t->ret = client_recv_buffer(pcd);
 187                 if (t->ret > 0)
 188                         pcd->status = CL_RECEIVED_WELCOME;
 189                 return;
 190         case CL_RECEIVED_WELCOME: /* send auth command */
 191                 sprintf(pcd->buf, "auth %s%s", pcd->conf.plain_given?
 192                         "" : "rc4 ", pcd->user);
 193                 PARA_INFO_LOG("--> %s\n", pcd->buf);
 194                 t->ret = send_buffer(pcd->fd, pcd->buf);
 195                 if (t->ret >= 0)
 196                         pcd->status = CL_SENT_AUTH;
 197                 return;
 198         case CL_SENT_AUTH: /* receive challenge number */
 199                 pcd->loaded = 0;
 200                 t->ret = client_recv_buffer(pcd);
 201                 if (t->ret < 0)
 202                         return;
 203                 if (t->ret != 64) {
 204                         t->ret = -E_INVALID_CHALLENGE;
 205                         PARA_ERROR_LOG("received the following: %s\n", pcd->buf);
 206                         return;
 207                 }
 208                 PARA_INFO_LOG("%s", "<-- [challenge]\n");
 209                 /* decrypt challenge number */
 210                 t->ret = para_decrypt_challenge(pcd->key_file, &pcd->challenge_nr,
 211                         (unsigned char *) pcd->buf, 64);
 212                 if (t->ret > 0)
 213                         pcd->status = CL_RECEIVED_CHALLENGE;
 214                 return;
 215         case CL_RECEIVED_CHALLENGE: /* send decrypted challenge */
 216                 PARA_INFO_LOG("--> %lu\n", pcd->challenge_nr);
 217                 t->ret = send_va_buffer(pcd->fd, "%s%lu", CHALLENGE_RESPONSE_MSG,
 218                         pcd->challenge_nr);
 219                 if (t->ret > 0)
 220                         pcd->status = CL_SENT_CH_RESPONSE;
 221                 return;
 222         case CL_SENT_CH_RESPONSE: /* read server response */
 223                 {
 224                 size_t bytes_received;
 225                 unsigned char rc4_buf[2 * RC4_KEY_LEN] = "";
 226                 pcd->loaded = 0;
 227                 t->ret = client_recv_buffer(pcd);
 228                 if (t->ret < 0)
 229                         return;
 230                 bytes_received = t->ret;
 231                 PARA_INFO_LOG("++++ server info ++++\n%s\n++++ end of server "
 232                         "info ++++\n", pcd->buf);
 233                 /* check if server has sent "Proceed" message */
 234                 t->ret = -E_CLIENT_AUTH;
 235                 if (!strstr(pcd->buf, PROCEED_MSG))
 236                         return;
 237                 t->ret = 1;
 238                 pcd->status = CL_RECEIVED_PROCEED;
 239                 if (bytes_received < PROCEED_MSG_LEN + 32)
 240                         return;
 241                 PARA_INFO_LOG("%s", "decrypting session key\n");
 242                 t->ret = para_decrypt_buffer(pcd->key_file, rc4_buf,
 243                         (unsigned char *)pcd->buf + PROCEED_MSG_LEN + 1,
 244                         bytes_received - PROCEED_MSG_LEN - 1);
 245                 if (t->ret < 0)
 246                         return;
 247                 RC4_set_key(&pcd->rc4_send_key, RC4_KEY_LEN, rc4_buf);
 248                 RC4_set_key(&pcd->rc4_recv_key, RC4_KEY_LEN, rc4_buf + RC4_KEY_LEN);
 249                 enable_crypt(pcd->fd, rc4_recv, rc4_send, pcd);
 250                 }
 251         case CL_RECEIVED_PROCEED: /* concat args and send command */
 252                 {
 253                 int i;
 254                 char *command = NULL;
 255                 for (i = 0; i < pcd->conf.inputs_num; i++) {
 256                         char *tmp = command;
 257                         command = make_message("%s\n%s", command?
 258                                 command : "", pcd->conf.inputs[i]);
 259                         free(tmp);
 260                 }
 261                 command = para_strcat(command, EOC_MSG "\n");
 262                 PARA_INFO_LOG("--> %s\n", command);
 263                 t->ret = send_buffer(pcd->fd, command);
 264                 free(command);
 265                 if (t->ret > 0)
 266                         pcd->status = CL_SENT_COMMAND;
 267                 return;
 268                 }
 269         case CL_SENT_COMMAND:
 270                 pcd->loaded = 0;
 271                 t->ret = client_recv_buffer(pcd);
 272                 if (t->ret < 0)
 273                         return;
 274                 t->ret = -E_HANDSHAKE_COMPLETE;
 275                 if (strstr(pcd->buf, AWAITING_DATA_MSG))
 276                         pcd->status = CL_SENDING_STDIN;
 277                 else
 278                         pcd->status = CL_RECEIVING_SERVER_OUTPUT;
 279                 return;
 280         case CL_SENDING_STDIN: /* FIXME: might block */
 281                 PARA_INFO_LOG("loaded: %zd\n", *pcd->in_loaded);
 282                 t->ret = send_bin_buffer(pcd->fd, pcd->inbuf, *pcd->in_loaded);
 283                 if (t->ret <= 0) {
 284                         if (!t->ret)
 285                                 t->ret = 1;
 286                         return;
 287                 }
 288                 *pcd->in_loaded = 0; /* FIXME: short writes */
 289                 return;
 290         case CL_RECEIVING_SERVER_OUTPUT:
 291                 t->ret = client_recv_buffer(pcd);
 292                 return;
 293         }
 294
 295 }
 296
 297 int client_open(struct private_client_data *pcd)
 298 {
 299         int ret;
 300         struct hostent *he;
 301         struct sockaddr_in their_addr;
 302
 303         /* get the host info */
 304         PARA_NOTICE_LOG("getting host info of %s\n",
 305                 pcd->conf.hostname_arg);
 306         ret = get_host_info(pcd->conf.hostname_arg, &he);
 307         if (ret < 0)
 308                 goto out;
 309         /* get new socket */
 310         ret = get_socket();
 311         if (ret < 0)
 312                 goto out;
 313         pcd->fd = ret;
 314         /* init their_addr */
 315         init_sockaddr(&their_addr, pcd->conf.server_port_arg, he);
 316         /* connect */
 317         PARA_NOTICE_LOG("connecting to %s\n", pcd->conf.hostname_arg);
 318         ret = para_connect(pcd->fd, &their_addr);
 319         if (ret < 0)
 320                 goto out;
 321         pcd->status = CL_CONNECTED;
 322         pcd->task.pre_select = client_pre_select;
 323         pcd->task.post_select = client_post_select;
 324         pcd->task.private_data = pcd;
 325         sprintf(pcd->task.status, "client");
 326         register_task(&pcd->task);
 327         ret = 1;
 328 out:
 329         return ret;
 330 }