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 "runopts.h"
  34
  35 #ifdef DROPBEAR_TCP_ACCEPT
  36
  37 static void cleanup_tcp(struct Listener *listener) {
  38
  39         struct TCPListener *tcpinfo = (struct TCPListener*)(listener->typedata);
  40
  41         m_free(tcpinfo->sendaddr);
  42         m_free(tcpinfo->listenaddr);
  43         m_free(tcpinfo);
  44 }
  45
  46 static void tcp_acceptor(struct Listener *listener, int sock) {
  47
  48         int fd;
  49         struct sockaddr_storage addr;
  50         socklen_t len;
  51         char ipstring[NI_MAXHOST], portstring[NI_MAXSERV];
  52         struct TCPListener *tcpinfo = (struct TCPListener*)(listener->typedata);
  53
  54         len = sizeof(addr);
  55
  56         fd = accept(sock, (struct sockaddr*)&addr, &len);
  57         if (fd < 0) {
  58                 return;
  59         }
  60
  61         if (getnameinfo((struct sockaddr*)&addr, len, ipstring, sizeof(ipstring),
  62                                 portstring, sizeof(portstring),
  63                                 NI_NUMERICHOST | NI_NUMERICSERV) != 0) {
  64                 m_close(fd);
  65                 return;
  66         }
  67
  68         if (send_msg_channel_open_init(fd, tcpinfo->chantype) == DROPBEAR_SUCCESS) {
  69                 unsigned char* addr = NULL;
  70                 unsigned int port = 0;
  71
  72                 if (tcpinfo->tcp_type == direct) {
  73                         /* "direct-tcpip" */
  74                         /* host to connect, port to connect */
  75                         addr = tcpinfo->sendaddr;
  76                         port = tcpinfo->sendport;
  77                 } else {
  78                         dropbear_assert(tcpinfo->tcp_type == forwarded);
  79                         /* "forwarded-tcpip" */
  80                         /* address that was connected, port that was connected */
  81                         addr = tcpinfo->listenaddr;
  82                         port = tcpinfo->listenport;
  83                 }
  84
  85                 if (addr == NULL) {
  86                         addr = "localhost";
  87                 }
  88                 buf_putstring(ses.writepayload, addr, strlen(addr));
  89                 buf_putint(ses.writepayload, port);
  90
  91                 /* originator ip */
  92                 buf_putstring(ses.writepayload, ipstring, strlen(ipstring));
  93                 /* originator port */
  94                 buf_putint(ses.writepayload, atol(portstring));
  95
  96                 encrypt_packet();
  97
  98         } else {
  99                 /* XXX debug? */
 100                 close(fd);
 101         }
 102 }
 103
 104 int listen_tcpfwd(struct TCPListener* tcpinfo) {
 105
 106         char portstring[NI_MAXSERV];
 107         int socks[DROPBEAR_MAX_SOCKS];
 108         struct Listener *listener = NULL;
 109         int nsocks;
 110         char* errstring = NULL;
 111
 112         TRACE(("enter listen_tcpfwd"))
 113
 114         /* first we try to bind, so don't need to do so much cleanup on failure */
 115         snprintf(portstring, sizeof(portstring), "%d", tcpinfo->listenport);
 116
 117         nsocks = dropbear_listen(tcpinfo->listenaddr, portstring, socks,
 118                         DROPBEAR_MAX_SOCKS, &errstring, &ses.maxfd);
 119         if (nsocks < 0) {
 120                 dropbear_log(LOG_INFO, "TCP forward failed: %s", errstring);
 121                 m_free(errstring);
 122                 TRACE(("leave listen_tcpfwd: dropbear_listen failed"))
 123                 return DROPBEAR_FAILURE;
 124         }
 125         m_free(errstring);
 126
 127         /* new_listener will close the socks if it fails */
 128         listener = new_listener(socks, nsocks, CHANNEL_ID_TCPFORWARDED, tcpinfo,
 129                         tcp_acceptor, cleanup_tcp);
 130
 131         if (listener == NULL) {
 132                 TRACE(("leave listen_tcpfwd: listener failed"))
 133                 return DROPBEAR_FAILURE;
 134         }
 135
 136         TRACE(("leave listen_tcpfwd: success"))
 137         return DROPBEAR_SUCCESS;
 138 }
 139
 140 #endif /* DROPBEAR_TCP_ACCEPT */