Mercurial > dropbear
annotate svr-tcpfwd.c @ 67:86725004a0ea
fake-rfc stuff
| author | Matt Johnston <matt@ucc.asn.au> |
|---|---|
| date | Thu, 12 Aug 2004 14:39:17 +0000 |
| parents | efb5e0b335cf |
| children | b0316ce64e4b |
| rev | line source |
|---|---|
| 62 | 1 #include "includes.h" |
| 2 #include "ssh.h" | |
| 64 | 3 #include "tcpfwd.h" |
| 62 | 4 #include "dbutil.h" |
| 5 #include "session.h" | |
| 6 #include "buffer.h" | |
| 7 #include "packet.h" | |
| 8 #include "listener.h" | |
| 9 #include "runopts.h" | |
| 10 | |
| 11 #ifndef DISABLE_SVR_REMOTETCPFWD | |
| 12 | |
| 13 static void send_msg_request_success(); | |
| 14 static void send_msg_request_failure(); | |
| 15 static int svr_cancelremotetcp(); | |
| 16 static int svr_remotetcpreq(); | |
| 64 | 17 static int newtcpdirect(struct Channel * channel); |
| 62 | 18 |
| 19 | |
| 20 const struct ChanType svr_chan_tcpdirect = { | |
| 21 1, /* sepfds */ | |
| 22 "direct-tcpip", | |
| 23 newtcpdirect, /* init */ | |
| 24 NULL, /* checkclose */ | |
| 25 NULL, /* reqhandler */ | |
| 26 NULL /* closehandler */ | |
| 27 }; | |
| 28 | |
| 29 static const struct ChanType svr_chan_tcpremote = { | |
| 30 1, /* sepfds */ | |
| 31 "forwarded-tcpip", | |
| 32 NULL, | |
| 33 NULL, | |
| 34 NULL, | |
| 35 NULL | |
| 36 }; | |
| 37 | |
| 38 /* At the moment this is completely used for tcp code (with the name reflecting | |
| 39 * that). If new request types are added, this should be replaced with code | |
| 40 * similar to the request-switching in chansession.c */ | |
| 41 void recv_msg_global_request_remotetcp() { | |
| 42 | |
| 43 unsigned char* reqname = NULL; | |
| 44 unsigned int namelen; | |
| 45 unsigned int wantreply = 0; | |
| 46 int ret = DROPBEAR_FAILURE; | |
| 47 | |
| 48 TRACE(("enter recv_msg_global_request_remotetcp")); | |
| 49 | |
| 50 if (opts.noremotetcp) { | |
| 51 TRACE(("leave recv_msg_global_request_remotetcp: remote tcp forwarding disabled")); | |
| 52 goto out; | |
| 53 } | |
| 54 | |
| 55 reqname = buf_getstring(ses.payload, &namelen); | |
| 56 wantreply = buf_getbyte(ses.payload); | |
| 57 | |
| 58 if (namelen > MAXNAMLEN) { | |
| 59 TRACE(("name len is wrong: %d", namelen)); | |
| 60 goto out; | |
| 61 } | |
| 62 | |
| 63 if (strcmp("tcpip-forward", reqname) == 0) { | |
| 64 ret = svr_remotetcpreq(); | |
| 65 } else if (strcmp("cancel-tcpip-forward", reqname) == 0) { | |
| 66 ret = svr_cancelremotetcp(); | |
| 67 } else { | |
| 68 TRACE(("reqname isn't tcpip-forward: '%s'", reqname)); | |
| 69 } | |
| 70 | |
| 71 out: | |
| 72 if (wantreply) { | |
| 73 if (ret == DROPBEAR_SUCCESS) { | |
| 74 send_msg_request_success(); | |
| 75 } else { | |
| 76 send_msg_request_failure(); | |
| 77 } | |
| 78 } | |
| 79 | |
| 80 m_free(reqname); | |
| 81 | |
| 82 TRACE(("leave recv_msg_global_request")); | |
| 83 } | |
| 84 | |
| 85 | |
| 86 static void send_msg_request_success() { | |
| 87 | |
| 88 CHECKCLEARTOWRITE(); | |
| 89 buf_putbyte(ses.writepayload, SSH_MSG_REQUEST_SUCCESS); | |
| 90 encrypt_packet(); | |
| 91 | |
| 92 } | |
| 93 | |
| 94 static void send_msg_request_failure() { | |
| 95 | |
| 96 CHECKCLEARTOWRITE(); | |
| 97 buf_putbyte(ses.writepayload, SSH_MSG_REQUEST_FAILURE); | |
| 98 encrypt_packet(); | |
| 99 | |
| 100 } | |
| 101 | |
| 102 static int matchtcp(void* typedata1, void* typedata2) { | |
| 103 | |
| 104 const struct TCPListener *info1 = (struct TCPListener*)typedata1; | |
| 105 const struct TCPListener *info2 = (struct TCPListener*)typedata2; | |
| 106 | |
|
63
dcc43965928f
- A nice cleaner structure for tcp (acceptor) forwarding.
Matt Johnston <matt@ucc.asn.au>
parents:
62
diff
changeset
|
107 return (info1->sendport == info2->sendport) |
| 62 | 108 && (info1->chantype == info2->chantype) |
|
63
dcc43965928f
- A nice cleaner structure for tcp (acceptor) forwarding.
Matt Johnston <matt@ucc.asn.au>
parents:
62
diff
changeset
|
109 && (strcmp(info1->sendaddr, info2->sendaddr) == 0); |
| 62 | 110 } |
| 111 | |
| 112 static int svr_cancelremotetcp() { | |
| 113 | |
| 114 int ret = DROPBEAR_FAILURE; | |
| 115 unsigned char * bindaddr = NULL; | |
| 116 unsigned int addrlen; | |
| 117 unsigned int port; | |
| 118 struct Listener * listener = NULL; | |
| 119 struct TCPListener tcpinfo; | |
| 120 | |
| 121 TRACE(("enter cancelremotetcp")); | |
| 122 | |
| 123 bindaddr = buf_getstring(ses.payload, &addrlen); | |
| 124 if (addrlen > MAX_IP_LEN) { | |
| 125 TRACE(("addr len too long: %d", addrlen)); | |
| 126 goto out; | |
| 127 } | |
| 128 | |
| 129 port = buf_getint(ses.payload); | |
| 130 | |
|
63
dcc43965928f
- A nice cleaner structure for tcp (acceptor) forwarding.
Matt Johnston <matt@ucc.asn.au>
parents:
62
diff
changeset
|
131 tcpinfo.sendaddr = bindaddr; |
|
dcc43965928f
- A nice cleaner structure for tcp (acceptor) forwarding.
Matt Johnston <matt@ucc.asn.au>
parents:
62
diff
changeset
|
132 tcpinfo.sendport = port; |
| 62 | 133 listener = get_listener(CHANNEL_ID_TCPFORWARDED, &tcpinfo, matchtcp); |
| 134 if (listener) { | |
| 135 remove_listener( listener ); | |
| 136 ret = DROPBEAR_SUCCESS; | |
| 137 } | |
| 138 | |
| 139 out: | |
| 140 m_free(bindaddr); | |
| 141 TRACE(("leave cancelremotetcp")); | |
| 142 return ret; | |
| 143 } | |
| 144 | |
| 145 static int svr_remotetcpreq() { | |
| 146 | |
| 147 int ret = DROPBEAR_FAILURE; | |
| 148 unsigned char * bindaddr = NULL; | |
| 149 unsigned int addrlen; | |
| 150 struct TCPListener *tcpinfo = NULL; | |
| 151 unsigned int port; | |
| 152 | |
| 153 TRACE(("enter remotetcpreq")); | |
| 154 | |
|
63
dcc43965928f
- A nice cleaner structure for tcp (acceptor) forwarding.
Matt Johnston <matt@ucc.asn.au>
parents:
62
diff
changeset
|
155 /* NOTE: at this stage, we ignore bindaddr. see below and listen_tcpfwd */ |
| 62 | 156 bindaddr = buf_getstring(ses.payload, &addrlen); |
| 157 if (addrlen > MAX_IP_LEN) { | |
| 158 TRACE(("addr len too long: %d", addrlen)); | |
| 159 goto out; | |
| 160 } | |
| 161 | |
| 162 port = buf_getint(ses.payload); | |
| 163 | |
| 164 if (port == 0) { | |
| 165 dropbear_log(LOG_INFO, "Server chosen tcpfwd ports are unsupported"); | |
| 166 goto out; | |
| 167 } | |
| 168 | |
| 169 if (port < 1 || port > 65535) { | |
| 170 TRACE(("invalid port: %d", port)); | |
| 171 goto out; | |
| 172 } | |
| 173 | |
| 174 if (!ses.allowprivport && port < IPPORT_RESERVED) { | |
| 175 TRACE(("can't assign port < 1024 for non-root")); | |
| 176 goto out; | |
| 177 } | |
| 178 | |
| 179 tcpinfo = (struct TCPListener*)m_malloc(sizeof(struct TCPListener)); | |
|
63
dcc43965928f
- A nice cleaner structure for tcp (acceptor) forwarding.
Matt Johnston <matt@ucc.asn.au>
parents:
62
diff
changeset
|
180 tcpinfo->sendaddr = bindaddr; |
|
dcc43965928f
- A nice cleaner structure for tcp (acceptor) forwarding.
Matt Johnston <matt@ucc.asn.au>
parents:
62
diff
changeset
|
181 tcpinfo->sendport = port; |
| 64 | 182 tcpinfo->listenport = port; |
| 62 | 183 tcpinfo->chantype = &svr_chan_tcpremote; |
| 184 | |
|
63
dcc43965928f
- A nice cleaner structure for tcp (acceptor) forwarding.
Matt Johnston <matt@ucc.asn.au>
parents:
62
diff
changeset
|
185 /* Note: bindaddr is actually ignored by listen_tcpfwd, since |
|
dcc43965928f
- A nice cleaner structure for tcp (acceptor) forwarding.
Matt Johnston <matt@ucc.asn.au>
parents:
62
diff
changeset
|
186 * we only want to bind to localhost */ |
| 62 | 187 ret = listen_tcpfwd(tcpinfo); |
| 188 | |
| 189 out: | |
| 190 if (ret == DROPBEAR_FAILURE) { | |
| 191 /* we only free it if a listener wasn't created, since the listener | |
| 192 * has to remember it if it's to be cancelled */ | |
|
63
dcc43965928f
- A nice cleaner structure for tcp (acceptor) forwarding.
Matt Johnston <matt@ucc.asn.au>
parents:
62
diff
changeset
|
193 m_free(tcpinfo->sendaddr); |
| 62 | 194 m_free(tcpinfo); |
| 195 } | |
| 196 TRACE(("leave remotetcpreq")); | |
| 197 return ret; | |
| 198 } | |
| 64 | 199 |
| 200 /* Called upon creating a new direct tcp channel (ie we connect out to an | |
| 201 * address */ | |
| 202 static int newtcpdirect(struct Channel * channel) { | |
| 203 | |
| 204 unsigned char* desthost = NULL; | |
| 205 unsigned int destport; | |
| 206 unsigned char* orighost = NULL; | |
| 207 unsigned int origport; | |
| 208 char portstring[NI_MAXSERV]; | |
| 209 int sock; | |
| 210 int len; | |
| 211 int ret = DROPBEAR_FAILURE; | |
| 212 | |
| 213 if (opts.nolocaltcp) { | |
| 214 TRACE(("leave newtcpdirect: local tcp forwarding disabled")); | |
| 215 goto out; | |
| 216 } | |
| 217 | |
| 218 desthost = buf_getstring(ses.payload, &len); | |
| 219 if (len > MAX_HOST_LEN) { | |
| 220 TRACE(("leave newtcpdirect: desthost too long")); | |
| 221 goto out; | |
| 222 } | |
| 223 | |
| 224 destport = buf_getint(ses.payload); | |
| 225 | |
| 226 orighost = buf_getstring(ses.payload, &len); | |
| 227 if (len > MAX_HOST_LEN) { | |
| 228 TRACE(("leave newtcpdirect: orighost too long")); | |
| 229 goto out; | |
| 230 } | |
| 231 | |
| 232 origport = buf_getint(ses.payload); | |
| 233 | |
| 234 /* best be sure */ | |
| 235 if (origport > 65535 || destport > 65535) { | |
| 236 TRACE(("leave newtcpdirect: port > 65535")); | |
| 237 goto out; | |
| 238 } | |
| 239 | |
| 240 snprintf(portstring, sizeof(portstring), "%d", destport); | |
| 241 sock = connect_remote(desthost, portstring, 1, NULL); | |
| 242 if (sock < 0) { | |
| 243 TRACE(("leave newtcpdirect: sock failed")); | |
| 244 goto out; | |
| 245 } | |
| 246 | |
| 247 ses.maxfd = MAX(ses.maxfd, sock); | |
| 248 | |
| 249 /* Note that infd is actually the "outgoing" direction on the | |
| 250 * tcp connection, vice versa for outfd. | |
| 251 * We don't set outfd, that will get set after the connection's | |
| 252 * progress succeeds */ | |
| 253 channel->infd = sock; | |
| 254 channel->initconn = 1; | |
| 255 | |
| 256 ret = DROPBEAR_SUCCESS; | |
| 257 | |
| 258 out: | |
| 259 m_free(desthost); | |
| 260 m_free(orighost); | |
| 261 TRACE(("leave newtcpdirect: ret %d", ret)); | |
| 262 return ret; | |
| 263 } | |
| 264 | |
| 62 | 265 #endif |