release/src/router/dropbear/tcp-accept.c

   1 /*
   2  * Dropbear SSH
   3  *
   4  * Copyright (c) 2002,2003 Matt Johnston
   5  * All rights reserved.
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a copy
   8  * of this software and associated documentation files (the "Software"), to deal
   9  * in the Software without restriction, including without limitation the rights
  10  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  11  * copies of the Software, and to permit persons to whom the Software is
  12  * furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included in
  15  * all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  20  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  23  * SOFTWARE. */
  24
  25 #include "includes.h"
  26 #include "ssh.h"
  27 #include "tcpfwd.h"
  28 #include "dbutil.h"
  29 #include "session.h"
  30 #include "buffer.h"
  31 #include "packet.h"
  32 #include "listener.h"
  33 #include "listener.h"
  34 #include "runopts.h"
  35
  36 #ifdef DROPBEAR_TCP_ACCEPT
  37
  38 static void cleanup_tcp(struct Listener *listener) {
  39
  40         struct TCPListener *tcpinfo = (struct TCPListener*)(listener->typedata);
  41
  42         m_free(tcpinfo->sendaddr);
  43         m_free(tcpinfo->listenaddr);
  44         m_free(tcpinfo->request_listenaddr);
  45         m_free(tcpinfo);
  46 }
  47
  48 int tcp_prio_inithandler(struct Channel* channel)
  49 {
  50         TRACE(("tcp_prio_inithandler channel %d", channel->index))
  51         channel->prio = DROPBEAR_CHANNEL_PRIO_UNKNOWABLE;
  52         return 0;
  53 }
  54
  55 static void tcp_acceptor(struct Listener *listener, int sock) {
  56
  57         int fd;
  58         struct sockaddr_storage addr;
  59         socklen_t len;
  60         char ipstring[NI_MAXHOST], portstring[NI_MAXSERV];
  61         struct TCPListener *tcpinfo = (struct TCPListener*)(listener->typedata);
  62
  63         len = sizeof(addr);
  64
  65         fd = accept(sock, (struct sockaddr*)&addr, &len);
  66         if (fd < 0) {
  67                 return;
  68         }
  69
  70         if (getnameinfo((struct sockaddr*)&addr, len, ipstring, sizeof(ipstring),
  71                                 portstring, sizeof(portstring),
  72                                 NI_NUMERICHOST | NI_NUMERICSERV) != 0) {
  73                 m_close(fd);
  74                 return;
  75         }
  76
  77         if (send_msg_channel_open_init(fd, tcpinfo->chantype) == DROPBEAR_SUCCESS) {
  78                 char* addr = NULL;
  79                 unsigned int port = 0;
  80
  81                 if (tcpinfo->tcp_type == direct) {
  82                         /* "direct-tcpip" */
  83                         /* host to connect, port to connect */
  84                         addr = tcpinfo->sendaddr;
  85                         port = tcpinfo->sendport;
  86                 } else {
  87                         dropbear_assert(tcpinfo->tcp_type == forwarded);
  88                         /* "forwarded-tcpip" */
  89                         /* address that was connected, port that was connected */
  90                         addr = tcpinfo->request_listenaddr;
  91                         port = tcpinfo->listenport;
  92                 }
  93
  94                 if (addr == NULL) {
  95                         addr = "localhost";
  96                 }
  97                 buf_putstring(ses.writepayload, addr, strlen(addr));
  98                 buf_putint(ses.writepayload, port);
  99
 100                 /* originator ip */
 101                 buf_putstring(ses.writepayload, ipstring, strlen(ipstring));
 102                 /* originator port */
 103                 buf_putint(ses.writepayload, atol(portstring));
 104
 105                 encrypt_packet();
 106
 107         } else {
 108                 /* XXX debug? */
 109                 close(fd);
 110         }
 111 }
 112
 113 int listen_tcpfwd(struct TCPListener* tcpinfo) {
 114
 115         char portstring[NI_MAXSERV];
 116         int socks[DROPBEAR_MAX_SOCKS];
 117         struct Listener *listener = NULL;
 118         int nsocks;
 119         char* errstring = NULL;
 120
 121         TRACE(("enter listen_tcpfwd"))
 122
 123         /* first we try to bind, so don't need to do so much cleanup on failure */
 124         snprintf(portstring, sizeof(portstring), "%d", tcpinfo->listenport);
 125
 126         nsocks = dropbear_listen(tcpinfo->listenaddr, portstring, socks,
 127                         DROPBEAR_MAX_SOCKS, &errstring, &ses.maxfd);
 128         if (nsocks < 0) {
 129                 dropbear_log(LOG_INFO, "TCP forward failed: %s", errstring);
 130                 m_free(errstring);
 131                 TRACE(("leave listen_tcpfwd: dropbear_listen failed"))
 132                 return DROPBEAR_FAILURE;
 133         }
 134         m_free(errstring);
 135
 136         /* new_listener will close the socks if it fails */
 137         listener = new_listener(socks, nsocks, CHANNEL_ID_TCPFORWARDED, tcpinfo,
 138                         tcp_acceptor, cleanup_tcp);
 139
 140         if (listener == NULL) {
 141                 TRACE(("leave listen_tcpfwd: listener failed"))
 142                 return DROPBEAR_FAILURE;
 143         }
 144
 145         TRACE(("leave listen_tcpfwd: success"))
 146         return DROPBEAR_SUCCESS;
 147 }
 148
 149 #endif /* DROPBEAR_TCP_ACCEPT */