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