1*99e85e0dSPeter Avalos /* $OpenBSD: serverloop.c,v 1.162 2012/06/20 04:42:58 djm Exp $ */ 218de8d7fSPeter Avalos /* 318de8d7fSPeter Avalos * Author: Tatu Ylonen <ylo@cs.hut.fi> 418de8d7fSPeter Avalos * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland 518de8d7fSPeter Avalos * All rights reserved 618de8d7fSPeter Avalos * Server main loop for handling the interactive session. 718de8d7fSPeter Avalos * 818de8d7fSPeter Avalos * As far as I am concerned, the code I have written for this software 918de8d7fSPeter Avalos * can be used freely for any purpose. Any derived versions of this 1018de8d7fSPeter Avalos * software must be clearly marked as such, and if the derived work is 1118de8d7fSPeter Avalos * incompatible with the protocol description in the RFC file, it must be 1218de8d7fSPeter Avalos * called by a name other than "ssh" or "Secure Shell". 1318de8d7fSPeter Avalos * 1418de8d7fSPeter Avalos * SSH2 support by Markus Friedl. 1518de8d7fSPeter Avalos * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved. 1618de8d7fSPeter Avalos * 1718de8d7fSPeter Avalos * Redistribution and use in source and binary forms, with or without 1818de8d7fSPeter Avalos * modification, are permitted provided that the following conditions 1918de8d7fSPeter Avalos * are met: 2018de8d7fSPeter Avalos * 1. Redistributions of source code must retain the above copyright 2118de8d7fSPeter Avalos * notice, this list of conditions and the following disclaimer. 2218de8d7fSPeter Avalos * 2. Redistributions in binary form must reproduce the above copyright 2318de8d7fSPeter Avalos * notice, this list of conditions and the following disclaimer in the 2418de8d7fSPeter Avalos * documentation and/or other materials provided with the distribution. 2518de8d7fSPeter Avalos * 2618de8d7fSPeter Avalos * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 2718de8d7fSPeter Avalos * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 2818de8d7fSPeter Avalos * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 2918de8d7fSPeter Avalos * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 3018de8d7fSPeter Avalos * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 3118de8d7fSPeter Avalos * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 3218de8d7fSPeter Avalos * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 3318de8d7fSPeter Avalos * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 3418de8d7fSPeter Avalos * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 3518de8d7fSPeter Avalos * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 3618de8d7fSPeter Avalos */ 3718de8d7fSPeter Avalos 3818de8d7fSPeter Avalos #include "includes.h" 3918de8d7fSPeter Avalos 4018de8d7fSPeter Avalos #include <sys/types.h> 4118de8d7fSPeter Avalos #include <sys/param.h> 4218de8d7fSPeter Avalos #include <sys/wait.h> 4318de8d7fSPeter Avalos #include <sys/socket.h> 4418de8d7fSPeter Avalos #ifdef HAVE_SYS_TIME_H 4518de8d7fSPeter Avalos # include <sys/time.h> 4618de8d7fSPeter Avalos #endif 4718de8d7fSPeter Avalos 4818de8d7fSPeter Avalos #include <netinet/in.h> 4918de8d7fSPeter Avalos 5018de8d7fSPeter Avalos #include <errno.h> 5118de8d7fSPeter Avalos #include <fcntl.h> 5218de8d7fSPeter Avalos #include <pwd.h> 5318de8d7fSPeter Avalos #include <signal.h> 5418de8d7fSPeter Avalos #include <string.h> 5518de8d7fSPeter Avalos #include <termios.h> 5618de8d7fSPeter Avalos #include <unistd.h> 5718de8d7fSPeter Avalos #include <stdarg.h> 5818de8d7fSPeter Avalos 5918de8d7fSPeter Avalos #include "openbsd-compat/sys-queue.h" 6018de8d7fSPeter Avalos #include "xmalloc.h" 6118de8d7fSPeter Avalos #include "packet.h" 6218de8d7fSPeter Avalos #include "buffer.h" 6318de8d7fSPeter Avalos #include "log.h" 6418de8d7fSPeter Avalos #include "servconf.h" 6518de8d7fSPeter Avalos #include "canohost.h" 6618de8d7fSPeter Avalos #include "sshpty.h" 6718de8d7fSPeter Avalos #include "channels.h" 6818de8d7fSPeter Avalos #include "compat.h" 6918de8d7fSPeter Avalos #include "ssh1.h" 7018de8d7fSPeter Avalos #include "ssh2.h" 7118de8d7fSPeter Avalos #include "key.h" 7218de8d7fSPeter Avalos #include "cipher.h" 7318de8d7fSPeter Avalos #include "kex.h" 7418de8d7fSPeter Avalos #include "hostfile.h" 7518de8d7fSPeter Avalos #include "auth.h" 7618de8d7fSPeter Avalos #include "session.h" 7718de8d7fSPeter Avalos #include "dispatch.h" 7818de8d7fSPeter Avalos #include "auth-options.h" 7918de8d7fSPeter Avalos #include "serverloop.h" 8018de8d7fSPeter Avalos #include "misc.h" 8140c002afSPeter Avalos #include "roaming.h" 8218de8d7fSPeter Avalos 8318de8d7fSPeter Avalos extern ServerOptions options; 8418de8d7fSPeter Avalos 8518de8d7fSPeter Avalos /* XXX */ 8618de8d7fSPeter Avalos extern Kex *xxx_kex; 8718de8d7fSPeter Avalos extern Authctxt *the_authctxt; 8818de8d7fSPeter Avalos extern int use_privsep; 8918de8d7fSPeter Avalos 9018de8d7fSPeter Avalos static Buffer stdin_buffer; /* Buffer for stdin data. */ 9118de8d7fSPeter Avalos static Buffer stdout_buffer; /* Buffer for stdout data. */ 9218de8d7fSPeter Avalos static Buffer stderr_buffer; /* Buffer for stderr data. */ 9318de8d7fSPeter Avalos static int fdin; /* Descriptor for stdin (for writing) */ 9418de8d7fSPeter Avalos static int fdout; /* Descriptor for stdout (for reading); 9518de8d7fSPeter Avalos May be same number as fdin. */ 9618de8d7fSPeter Avalos static int fderr; /* Descriptor for stderr. May be -1. */ 9718de8d7fSPeter Avalos static long stdin_bytes = 0; /* Number of bytes written to stdin. */ 9818de8d7fSPeter Avalos static long stdout_bytes = 0; /* Number of stdout bytes sent to client. */ 9918de8d7fSPeter Avalos static long stderr_bytes = 0; /* Number of stderr bytes sent to client. */ 10018de8d7fSPeter Avalos static long fdout_bytes = 0; /* Number of stdout bytes read from program. */ 10118de8d7fSPeter Avalos static int stdin_eof = 0; /* EOF message received from client. */ 10218de8d7fSPeter Avalos static int fdout_eof = 0; /* EOF encountered reading from fdout. */ 10318de8d7fSPeter Avalos static int fderr_eof = 0; /* EOF encountered readung from fderr. */ 10418de8d7fSPeter Avalos static int fdin_is_tty = 0; /* fdin points to a tty. */ 10518de8d7fSPeter Avalos static int connection_in; /* Connection to client (input). */ 10618de8d7fSPeter Avalos static int connection_out; /* Connection to client (output). */ 10718de8d7fSPeter Avalos static int connection_closed = 0; /* Connection to client closed. */ 10818de8d7fSPeter Avalos static u_int buffer_high; /* "Soft" max buffer size. */ 10918de8d7fSPeter Avalos static int no_more_sessions = 0; /* Disallow further sessions. */ 11018de8d7fSPeter Avalos 11118de8d7fSPeter Avalos /* 11218de8d7fSPeter Avalos * This SIGCHLD kludge is used to detect when the child exits. The server 11318de8d7fSPeter Avalos * will exit after that, as soon as forwarded connections have terminated. 11418de8d7fSPeter Avalos */ 11518de8d7fSPeter Avalos 11618de8d7fSPeter Avalos static volatile sig_atomic_t child_terminated = 0; /* The child has terminated. */ 11718de8d7fSPeter Avalos 11818de8d7fSPeter Avalos /* Cleanup on signals (!use_privsep case only) */ 11918de8d7fSPeter Avalos static volatile sig_atomic_t received_sigterm = 0; 12018de8d7fSPeter Avalos 12118de8d7fSPeter Avalos /* prototypes */ 12218de8d7fSPeter Avalos static void server_init_dispatch(void); 12318de8d7fSPeter Avalos 12418de8d7fSPeter Avalos /* 12518de8d7fSPeter Avalos * we write to this pipe if a SIGCHLD is caught in order to avoid 12618de8d7fSPeter Avalos * the race between select() and child_terminated 12718de8d7fSPeter Avalos */ 12818de8d7fSPeter Avalos static int notify_pipe[2]; 12918de8d7fSPeter Avalos static void 13018de8d7fSPeter Avalos notify_setup(void) 13118de8d7fSPeter Avalos { 13218de8d7fSPeter Avalos if (pipe(notify_pipe) < 0) { 13318de8d7fSPeter Avalos error("pipe(notify_pipe) failed %s", strerror(errno)); 1341c188a7fSPeter Avalos } else if ((fcntl(notify_pipe[0], F_SETFD, FD_CLOEXEC) == -1) || 1351c188a7fSPeter Avalos (fcntl(notify_pipe[1], F_SETFD, FD_CLOEXEC) == -1)) { 13618de8d7fSPeter Avalos error("fcntl(notify_pipe, F_SETFD) failed %s", strerror(errno)); 13718de8d7fSPeter Avalos close(notify_pipe[0]); 13818de8d7fSPeter Avalos close(notify_pipe[1]); 13918de8d7fSPeter Avalos } else { 14018de8d7fSPeter Avalos set_nonblock(notify_pipe[0]); 14118de8d7fSPeter Avalos set_nonblock(notify_pipe[1]); 14218de8d7fSPeter Avalos return; 14318de8d7fSPeter Avalos } 14418de8d7fSPeter Avalos notify_pipe[0] = -1; /* read end */ 14518de8d7fSPeter Avalos notify_pipe[1] = -1; /* write end */ 14618de8d7fSPeter Avalos } 14718de8d7fSPeter Avalos static void 14818de8d7fSPeter Avalos notify_parent(void) 14918de8d7fSPeter Avalos { 15018de8d7fSPeter Avalos if (notify_pipe[1] != -1) 15118de8d7fSPeter Avalos write(notify_pipe[1], "", 1); 15218de8d7fSPeter Avalos } 15318de8d7fSPeter Avalos static void 15418de8d7fSPeter Avalos notify_prepare(fd_set *readset) 15518de8d7fSPeter Avalos { 15618de8d7fSPeter Avalos if (notify_pipe[0] != -1) 15718de8d7fSPeter Avalos FD_SET(notify_pipe[0], readset); 15818de8d7fSPeter Avalos } 15918de8d7fSPeter Avalos static void 16018de8d7fSPeter Avalos notify_done(fd_set *readset) 16118de8d7fSPeter Avalos { 16218de8d7fSPeter Avalos char c; 16318de8d7fSPeter Avalos 16418de8d7fSPeter Avalos if (notify_pipe[0] != -1 && FD_ISSET(notify_pipe[0], readset)) 16518de8d7fSPeter Avalos while (read(notify_pipe[0], &c, 1) != -1) 16618de8d7fSPeter Avalos debug2("notify_done: reading"); 16718de8d7fSPeter Avalos } 16818de8d7fSPeter Avalos 16918de8d7fSPeter Avalos /*ARGSUSED*/ 17018de8d7fSPeter Avalos static void 17118de8d7fSPeter Avalos sigchld_handler(int sig) 17218de8d7fSPeter Avalos { 17318de8d7fSPeter Avalos int save_errno = errno; 17418de8d7fSPeter Avalos child_terminated = 1; 17518de8d7fSPeter Avalos #ifndef _UNICOS 17618de8d7fSPeter Avalos mysignal(SIGCHLD, sigchld_handler); 17718de8d7fSPeter Avalos #endif 17818de8d7fSPeter Avalos notify_parent(); 17918de8d7fSPeter Avalos errno = save_errno; 18018de8d7fSPeter Avalos } 18118de8d7fSPeter Avalos 18218de8d7fSPeter Avalos /*ARGSUSED*/ 18318de8d7fSPeter Avalos static void 18418de8d7fSPeter Avalos sigterm_handler(int sig) 18518de8d7fSPeter Avalos { 18618de8d7fSPeter Avalos received_sigterm = sig; 18718de8d7fSPeter Avalos } 18818de8d7fSPeter Avalos 18918de8d7fSPeter Avalos /* 19018de8d7fSPeter Avalos * Make packets from buffered stderr data, and buffer it for sending 19118de8d7fSPeter Avalos * to the client. 19218de8d7fSPeter Avalos */ 19318de8d7fSPeter Avalos static void 19418de8d7fSPeter Avalos make_packets_from_stderr_data(void) 19518de8d7fSPeter Avalos { 19618de8d7fSPeter Avalos u_int len; 19718de8d7fSPeter Avalos 19818de8d7fSPeter Avalos /* Send buffered stderr data to the client. */ 19918de8d7fSPeter Avalos while (buffer_len(&stderr_buffer) > 0 && 20018de8d7fSPeter Avalos packet_not_very_much_data_to_write()) { 20118de8d7fSPeter Avalos len = buffer_len(&stderr_buffer); 20218de8d7fSPeter Avalos if (packet_is_interactive()) { 20318de8d7fSPeter Avalos if (len > 512) 20418de8d7fSPeter Avalos len = 512; 20518de8d7fSPeter Avalos } else { 20618de8d7fSPeter Avalos /* Keep the packets at reasonable size. */ 20718de8d7fSPeter Avalos if (len > packet_get_maxsize()) 20818de8d7fSPeter Avalos len = packet_get_maxsize(); 20918de8d7fSPeter Avalos } 21018de8d7fSPeter Avalos packet_start(SSH_SMSG_STDERR_DATA); 21118de8d7fSPeter Avalos packet_put_string(buffer_ptr(&stderr_buffer), len); 21218de8d7fSPeter Avalos packet_send(); 21318de8d7fSPeter Avalos buffer_consume(&stderr_buffer, len); 21418de8d7fSPeter Avalos stderr_bytes += len; 21518de8d7fSPeter Avalos } 21618de8d7fSPeter Avalos } 21718de8d7fSPeter Avalos 21818de8d7fSPeter Avalos /* 21918de8d7fSPeter Avalos * Make packets from buffered stdout data, and buffer it for sending to the 22018de8d7fSPeter Avalos * client. 22118de8d7fSPeter Avalos */ 22218de8d7fSPeter Avalos static void 22318de8d7fSPeter Avalos make_packets_from_stdout_data(void) 22418de8d7fSPeter Avalos { 22518de8d7fSPeter Avalos u_int len; 22618de8d7fSPeter Avalos 22718de8d7fSPeter Avalos /* Send buffered stdout data to the client. */ 22818de8d7fSPeter Avalos while (buffer_len(&stdout_buffer) > 0 && 22918de8d7fSPeter Avalos packet_not_very_much_data_to_write()) { 23018de8d7fSPeter Avalos len = buffer_len(&stdout_buffer); 23118de8d7fSPeter Avalos if (packet_is_interactive()) { 23218de8d7fSPeter Avalos if (len > 512) 23318de8d7fSPeter Avalos len = 512; 23418de8d7fSPeter Avalos } else { 23518de8d7fSPeter Avalos /* Keep the packets at reasonable size. */ 23618de8d7fSPeter Avalos if (len > packet_get_maxsize()) 23718de8d7fSPeter Avalos len = packet_get_maxsize(); 23818de8d7fSPeter Avalos } 23918de8d7fSPeter Avalos packet_start(SSH_SMSG_STDOUT_DATA); 24018de8d7fSPeter Avalos packet_put_string(buffer_ptr(&stdout_buffer), len); 24118de8d7fSPeter Avalos packet_send(); 24218de8d7fSPeter Avalos buffer_consume(&stdout_buffer, len); 24318de8d7fSPeter Avalos stdout_bytes += len; 24418de8d7fSPeter Avalos } 24518de8d7fSPeter Avalos } 24618de8d7fSPeter Avalos 24718de8d7fSPeter Avalos static void 24818de8d7fSPeter Avalos client_alive_check(void) 24918de8d7fSPeter Avalos { 25018de8d7fSPeter Avalos int channel_id; 25118de8d7fSPeter Avalos 25218de8d7fSPeter Avalos /* timeout, check to see how many we have had */ 25340c002afSPeter Avalos if (packet_inc_alive_timeouts() > options.client_alive_count_max) { 25418de8d7fSPeter Avalos logit("Timeout, client not responding."); 25518de8d7fSPeter Avalos cleanup_exit(255); 25618de8d7fSPeter Avalos } 25718de8d7fSPeter Avalos 25818de8d7fSPeter Avalos /* 25918de8d7fSPeter Avalos * send a bogus global/channel request with "wantreply", 26018de8d7fSPeter Avalos * we should get back a failure 26118de8d7fSPeter Avalos */ 26218de8d7fSPeter Avalos if ((channel_id = channel_find_open()) == -1) { 26318de8d7fSPeter Avalos packet_start(SSH2_MSG_GLOBAL_REQUEST); 26418de8d7fSPeter Avalos packet_put_cstring("keepalive@openssh.com"); 26518de8d7fSPeter Avalos packet_put_char(1); /* boolean: want reply */ 26618de8d7fSPeter Avalos } else { 26718de8d7fSPeter Avalos channel_request_start(channel_id, "keepalive@openssh.com", 1); 26818de8d7fSPeter Avalos } 26918de8d7fSPeter Avalos packet_send(); 27018de8d7fSPeter Avalos } 27118de8d7fSPeter Avalos 27218de8d7fSPeter Avalos /* 27318de8d7fSPeter Avalos * Sleep in select() until we can do something. This will initialize the 27418de8d7fSPeter Avalos * select masks. Upon return, the masks will indicate which descriptors 27518de8d7fSPeter Avalos * have data or can accept data. Optionally, a maximum time can be specified 27618de8d7fSPeter Avalos * for the duration of the wait (0 = infinite). 27718de8d7fSPeter Avalos */ 27818de8d7fSPeter Avalos static void 27918de8d7fSPeter Avalos wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp, int *maxfdp, 28018de8d7fSPeter Avalos u_int *nallocp, u_int max_time_milliseconds) 28118de8d7fSPeter Avalos { 28218de8d7fSPeter Avalos struct timeval tv, *tvp; 28318de8d7fSPeter Avalos int ret; 284*99e85e0dSPeter Avalos time_t minwait_secs = 0; 28518de8d7fSPeter Avalos int client_alive_scheduled = 0; 28618de8d7fSPeter Avalos int program_alive_scheduled = 0; 28718de8d7fSPeter Avalos 288*99e85e0dSPeter Avalos /* Allocate and update select() masks for channel descriptors. */ 289*99e85e0dSPeter Avalos channel_prepare_select(readsetp, writesetp, maxfdp, nallocp, 290*99e85e0dSPeter Avalos &minwait_secs, 0); 291*99e85e0dSPeter Avalos 292*99e85e0dSPeter Avalos if (minwait_secs != 0) 293*99e85e0dSPeter Avalos max_time_milliseconds = MIN(max_time_milliseconds, 294*99e85e0dSPeter Avalos (u_int)minwait_secs * 1000); 295*99e85e0dSPeter Avalos 29618de8d7fSPeter Avalos /* 29718de8d7fSPeter Avalos * if using client_alive, set the max timeout accordingly, 29818de8d7fSPeter Avalos * and indicate that this particular timeout was for client 29918de8d7fSPeter Avalos * alive by setting the client_alive_scheduled flag. 30018de8d7fSPeter Avalos * 30118de8d7fSPeter Avalos * this could be randomized somewhat to make traffic 30218de8d7fSPeter Avalos * analysis more difficult, but we're not doing it yet. 30318de8d7fSPeter Avalos */ 30418de8d7fSPeter Avalos if (compat20 && 30518de8d7fSPeter Avalos max_time_milliseconds == 0 && options.client_alive_interval) { 30618de8d7fSPeter Avalos client_alive_scheduled = 1; 30718de8d7fSPeter Avalos max_time_milliseconds = options.client_alive_interval * 1000; 30818de8d7fSPeter Avalos } 30918de8d7fSPeter Avalos 31018de8d7fSPeter Avalos if (compat20) { 31118de8d7fSPeter Avalos #if 0 31218de8d7fSPeter Avalos /* wrong: bad condition XXX */ 31318de8d7fSPeter Avalos if (channel_not_very_much_buffered_data()) 31418de8d7fSPeter Avalos #endif 31518de8d7fSPeter Avalos FD_SET(connection_in, *readsetp); 31618de8d7fSPeter Avalos } else { 31718de8d7fSPeter Avalos /* 31818de8d7fSPeter Avalos * Read packets from the client unless we have too much 31918de8d7fSPeter Avalos * buffered stdin or channel data. 32018de8d7fSPeter Avalos */ 32118de8d7fSPeter Avalos if (buffer_len(&stdin_buffer) < buffer_high && 32218de8d7fSPeter Avalos channel_not_very_much_buffered_data()) 32318de8d7fSPeter Avalos FD_SET(connection_in, *readsetp); 32418de8d7fSPeter Avalos /* 32518de8d7fSPeter Avalos * If there is not too much data already buffered going to 32618de8d7fSPeter Avalos * the client, try to get some more data from the program. 32718de8d7fSPeter Avalos */ 32818de8d7fSPeter Avalos if (packet_not_very_much_data_to_write()) { 32918de8d7fSPeter Avalos program_alive_scheduled = child_terminated; 33018de8d7fSPeter Avalos if (!fdout_eof) 33118de8d7fSPeter Avalos FD_SET(fdout, *readsetp); 33218de8d7fSPeter Avalos if (!fderr_eof) 33318de8d7fSPeter Avalos FD_SET(fderr, *readsetp); 33418de8d7fSPeter Avalos } 33518de8d7fSPeter Avalos /* 33618de8d7fSPeter Avalos * If we have buffered data, try to write some of that data 33718de8d7fSPeter Avalos * to the program. 33818de8d7fSPeter Avalos */ 33918de8d7fSPeter Avalos if (fdin != -1 && buffer_len(&stdin_buffer) > 0) 34018de8d7fSPeter Avalos FD_SET(fdin, *writesetp); 34118de8d7fSPeter Avalos } 34218de8d7fSPeter Avalos notify_prepare(*readsetp); 34318de8d7fSPeter Avalos 34418de8d7fSPeter Avalos /* 34518de8d7fSPeter Avalos * If we have buffered packet data going to the client, mark that 34618de8d7fSPeter Avalos * descriptor. 34718de8d7fSPeter Avalos */ 34818de8d7fSPeter Avalos if (packet_have_data_to_write()) 34918de8d7fSPeter Avalos FD_SET(connection_out, *writesetp); 35018de8d7fSPeter Avalos 35118de8d7fSPeter Avalos /* 35218de8d7fSPeter Avalos * If child has terminated and there is enough buffer space to read 35318de8d7fSPeter Avalos * from it, then read as much as is available and exit. 35418de8d7fSPeter Avalos */ 35518de8d7fSPeter Avalos if (child_terminated && packet_not_very_much_data_to_write()) 35618de8d7fSPeter Avalos if (max_time_milliseconds == 0 || client_alive_scheduled) 35718de8d7fSPeter Avalos max_time_milliseconds = 100; 35818de8d7fSPeter Avalos 35918de8d7fSPeter Avalos if (max_time_milliseconds == 0) 36018de8d7fSPeter Avalos tvp = NULL; 36118de8d7fSPeter Avalos else { 36218de8d7fSPeter Avalos tv.tv_sec = max_time_milliseconds / 1000; 36318de8d7fSPeter Avalos tv.tv_usec = 1000 * (max_time_milliseconds % 1000); 36418de8d7fSPeter Avalos tvp = &tv; 36518de8d7fSPeter Avalos } 36618de8d7fSPeter Avalos 36718de8d7fSPeter Avalos /* Wait for something to happen, or the timeout to expire. */ 36818de8d7fSPeter Avalos ret = select((*maxfdp)+1, *readsetp, *writesetp, NULL, tvp); 36918de8d7fSPeter Avalos 37018de8d7fSPeter Avalos if (ret == -1) { 37118de8d7fSPeter Avalos memset(*readsetp, 0, *nallocp); 37218de8d7fSPeter Avalos memset(*writesetp, 0, *nallocp); 37318de8d7fSPeter Avalos if (errno != EINTR) 37418de8d7fSPeter Avalos error("select: %.100s", strerror(errno)); 37518de8d7fSPeter Avalos } else { 37618de8d7fSPeter Avalos if (ret == 0 && client_alive_scheduled) 37718de8d7fSPeter Avalos client_alive_check(); 37818de8d7fSPeter Avalos if (!compat20 && program_alive_scheduled && fdin_is_tty) { 37918de8d7fSPeter Avalos if (!fdout_eof) 38018de8d7fSPeter Avalos FD_SET(fdout, *readsetp); 38118de8d7fSPeter Avalos if (!fderr_eof) 38218de8d7fSPeter Avalos FD_SET(fderr, *readsetp); 38318de8d7fSPeter Avalos } 38418de8d7fSPeter Avalos } 38518de8d7fSPeter Avalos 38618de8d7fSPeter Avalos notify_done(*readsetp); 38718de8d7fSPeter Avalos } 38818de8d7fSPeter Avalos 38918de8d7fSPeter Avalos /* 39018de8d7fSPeter Avalos * Processes input from the client and the program. Input data is stored 39118de8d7fSPeter Avalos * in buffers and processed later. 39218de8d7fSPeter Avalos */ 39318de8d7fSPeter Avalos static void 39418de8d7fSPeter Avalos process_input(fd_set *readset) 39518de8d7fSPeter Avalos { 39618de8d7fSPeter Avalos int len; 39718de8d7fSPeter Avalos char buf[16384]; 39818de8d7fSPeter Avalos 39918de8d7fSPeter Avalos /* Read and buffer any input data from the client. */ 40018de8d7fSPeter Avalos if (FD_ISSET(connection_in, readset)) { 40140c002afSPeter Avalos int cont = 0; 40240c002afSPeter Avalos len = roaming_read(connection_in, buf, sizeof(buf), &cont); 40318de8d7fSPeter Avalos if (len == 0) { 40440c002afSPeter Avalos if (cont) 40540c002afSPeter Avalos return; 40618de8d7fSPeter Avalos verbose("Connection closed by %.100s", 40718de8d7fSPeter Avalos get_remote_ipaddr()); 40818de8d7fSPeter Avalos connection_closed = 1; 40918de8d7fSPeter Avalos if (compat20) 41018de8d7fSPeter Avalos return; 41118de8d7fSPeter Avalos cleanup_exit(255); 41218de8d7fSPeter Avalos } else if (len < 0) { 41318de8d7fSPeter Avalos if (errno != EINTR && errno != EAGAIN && 41418de8d7fSPeter Avalos errno != EWOULDBLOCK) { 41518de8d7fSPeter Avalos verbose("Read error from remote host " 41618de8d7fSPeter Avalos "%.100s: %.100s", 41718de8d7fSPeter Avalos get_remote_ipaddr(), strerror(errno)); 41818de8d7fSPeter Avalos cleanup_exit(255); 41918de8d7fSPeter Avalos } 42018de8d7fSPeter Avalos } else { 42118de8d7fSPeter Avalos /* Buffer any received data. */ 42218de8d7fSPeter Avalos packet_process_incoming(buf, len); 42318de8d7fSPeter Avalos } 42418de8d7fSPeter Avalos } 42518de8d7fSPeter Avalos if (compat20) 42618de8d7fSPeter Avalos return; 42718de8d7fSPeter Avalos 42818de8d7fSPeter Avalos /* Read and buffer any available stdout data from the program. */ 42918de8d7fSPeter Avalos if (!fdout_eof && FD_ISSET(fdout, readset)) { 43018de8d7fSPeter Avalos errno = 0; 43118de8d7fSPeter Avalos len = read(fdout, buf, sizeof(buf)); 43218de8d7fSPeter Avalos if (len < 0 && (errno == EINTR || ((errno == EAGAIN || 43318de8d7fSPeter Avalos errno == EWOULDBLOCK) && !child_terminated))) { 43418de8d7fSPeter Avalos /* do nothing */ 43518de8d7fSPeter Avalos #ifndef PTY_ZEROREAD 43618de8d7fSPeter Avalos } else if (len <= 0) { 43718de8d7fSPeter Avalos #else 43818de8d7fSPeter Avalos } else if ((!isatty(fdout) && len <= 0) || 43918de8d7fSPeter Avalos (isatty(fdout) && (len < 0 || (len == 0 && errno != 0)))) { 44018de8d7fSPeter Avalos #endif 44118de8d7fSPeter Avalos fdout_eof = 1; 44218de8d7fSPeter Avalos } else { 44318de8d7fSPeter Avalos buffer_append(&stdout_buffer, buf, len); 44418de8d7fSPeter Avalos fdout_bytes += len; 44518de8d7fSPeter Avalos } 44618de8d7fSPeter Avalos } 44718de8d7fSPeter Avalos /* Read and buffer any available stderr data from the program. */ 44818de8d7fSPeter Avalos if (!fderr_eof && FD_ISSET(fderr, readset)) { 44918de8d7fSPeter Avalos errno = 0; 45018de8d7fSPeter Avalos len = read(fderr, buf, sizeof(buf)); 45118de8d7fSPeter Avalos if (len < 0 && (errno == EINTR || ((errno == EAGAIN || 45218de8d7fSPeter Avalos errno == EWOULDBLOCK) && !child_terminated))) { 45318de8d7fSPeter Avalos /* do nothing */ 45418de8d7fSPeter Avalos #ifndef PTY_ZEROREAD 45518de8d7fSPeter Avalos } else if (len <= 0) { 45618de8d7fSPeter Avalos #else 45718de8d7fSPeter Avalos } else if ((!isatty(fderr) && len <= 0) || 45818de8d7fSPeter Avalos (isatty(fderr) && (len < 0 || (len == 0 && errno != 0)))) { 45918de8d7fSPeter Avalos #endif 46018de8d7fSPeter Avalos fderr_eof = 1; 46118de8d7fSPeter Avalos } else { 46218de8d7fSPeter Avalos buffer_append(&stderr_buffer, buf, len); 46318de8d7fSPeter Avalos } 46418de8d7fSPeter Avalos } 46518de8d7fSPeter Avalos } 46618de8d7fSPeter Avalos 46718de8d7fSPeter Avalos /* 46818de8d7fSPeter Avalos * Sends data from internal buffers to client program stdin. 46918de8d7fSPeter Avalos */ 47018de8d7fSPeter Avalos static void 47118de8d7fSPeter Avalos process_output(fd_set *writeset) 47218de8d7fSPeter Avalos { 47318de8d7fSPeter Avalos struct termios tio; 47418de8d7fSPeter Avalos u_char *data; 47518de8d7fSPeter Avalos u_int dlen; 47618de8d7fSPeter Avalos int len; 47718de8d7fSPeter Avalos 47818de8d7fSPeter Avalos /* Write buffered data to program stdin. */ 47918de8d7fSPeter Avalos if (!compat20 && fdin != -1 && FD_ISSET(fdin, writeset)) { 48018de8d7fSPeter Avalos data = buffer_ptr(&stdin_buffer); 48118de8d7fSPeter Avalos dlen = buffer_len(&stdin_buffer); 48218de8d7fSPeter Avalos len = write(fdin, data, dlen); 48318de8d7fSPeter Avalos if (len < 0 && 48418de8d7fSPeter Avalos (errno == EINTR || errno == EAGAIN || errno == EWOULDBLOCK)) { 48518de8d7fSPeter Avalos /* do nothing */ 48618de8d7fSPeter Avalos } else if (len <= 0) { 48718de8d7fSPeter Avalos if (fdin != fdout) 48818de8d7fSPeter Avalos close(fdin); 48918de8d7fSPeter Avalos else 49018de8d7fSPeter Avalos shutdown(fdin, SHUT_WR); /* We will no longer send. */ 49118de8d7fSPeter Avalos fdin = -1; 49218de8d7fSPeter Avalos } else { 49318de8d7fSPeter Avalos /* Successful write. */ 49418de8d7fSPeter Avalos if (fdin_is_tty && dlen >= 1 && data[0] != '\r' && 49518de8d7fSPeter Avalos tcgetattr(fdin, &tio) == 0 && 49618de8d7fSPeter Avalos !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) { 49718de8d7fSPeter Avalos /* 49818de8d7fSPeter Avalos * Simulate echo to reduce the impact of 49918de8d7fSPeter Avalos * traffic analysis 50018de8d7fSPeter Avalos */ 50118de8d7fSPeter Avalos packet_send_ignore(len); 50218de8d7fSPeter Avalos packet_send(); 50318de8d7fSPeter Avalos } 50418de8d7fSPeter Avalos /* Consume the data from the buffer. */ 50518de8d7fSPeter Avalos buffer_consume(&stdin_buffer, len); 50618de8d7fSPeter Avalos /* Update the count of bytes written to the program. */ 50718de8d7fSPeter Avalos stdin_bytes += len; 50818de8d7fSPeter Avalos } 50918de8d7fSPeter Avalos } 51018de8d7fSPeter Avalos /* Send any buffered packet data to the client. */ 51118de8d7fSPeter Avalos if (FD_ISSET(connection_out, writeset)) 51218de8d7fSPeter Avalos packet_write_poll(); 51318de8d7fSPeter Avalos } 51418de8d7fSPeter Avalos 51518de8d7fSPeter Avalos /* 51618de8d7fSPeter Avalos * Wait until all buffered output has been sent to the client. 51718de8d7fSPeter Avalos * This is used when the program terminates. 51818de8d7fSPeter Avalos */ 51918de8d7fSPeter Avalos static void 52018de8d7fSPeter Avalos drain_output(void) 52118de8d7fSPeter Avalos { 52218de8d7fSPeter Avalos /* Send any buffered stdout data to the client. */ 52318de8d7fSPeter Avalos if (buffer_len(&stdout_buffer) > 0) { 52418de8d7fSPeter Avalos packet_start(SSH_SMSG_STDOUT_DATA); 52518de8d7fSPeter Avalos packet_put_string(buffer_ptr(&stdout_buffer), 52618de8d7fSPeter Avalos buffer_len(&stdout_buffer)); 52718de8d7fSPeter Avalos packet_send(); 52818de8d7fSPeter Avalos /* Update the count of sent bytes. */ 52918de8d7fSPeter Avalos stdout_bytes += buffer_len(&stdout_buffer); 53018de8d7fSPeter Avalos } 53118de8d7fSPeter Avalos /* Send any buffered stderr data to the client. */ 53218de8d7fSPeter Avalos if (buffer_len(&stderr_buffer) > 0) { 53318de8d7fSPeter Avalos packet_start(SSH_SMSG_STDERR_DATA); 53418de8d7fSPeter Avalos packet_put_string(buffer_ptr(&stderr_buffer), 53518de8d7fSPeter Avalos buffer_len(&stderr_buffer)); 53618de8d7fSPeter Avalos packet_send(); 53718de8d7fSPeter Avalos /* Update the count of sent bytes. */ 53818de8d7fSPeter Avalos stderr_bytes += buffer_len(&stderr_buffer); 53918de8d7fSPeter Avalos } 54018de8d7fSPeter Avalos /* Wait until all buffered data has been written to the client. */ 54118de8d7fSPeter Avalos packet_write_wait(); 54218de8d7fSPeter Avalos } 54318de8d7fSPeter Avalos 54418de8d7fSPeter Avalos static void 54518de8d7fSPeter Avalos process_buffered_input_packets(void) 54618de8d7fSPeter Avalos { 54718de8d7fSPeter Avalos dispatch_run(DISPATCH_NONBLOCK, NULL, compat20 ? xxx_kex : NULL); 54818de8d7fSPeter Avalos } 54918de8d7fSPeter Avalos 55018de8d7fSPeter Avalos /* 55118de8d7fSPeter Avalos * Performs the interactive session. This handles data transmission between 55218de8d7fSPeter Avalos * the client and the program. Note that the notion of stdin, stdout, and 55318de8d7fSPeter Avalos * stderr in this function is sort of reversed: this function writes to 55418de8d7fSPeter Avalos * stdin (of the child program), and reads from stdout and stderr (of the 55518de8d7fSPeter Avalos * child program). 55618de8d7fSPeter Avalos */ 55718de8d7fSPeter Avalos void 55818de8d7fSPeter Avalos server_loop(pid_t pid, int fdin_arg, int fdout_arg, int fderr_arg) 55918de8d7fSPeter Avalos { 56018de8d7fSPeter Avalos fd_set *readset = NULL, *writeset = NULL; 56118de8d7fSPeter Avalos int max_fd = 0; 56218de8d7fSPeter Avalos u_int nalloc = 0; 56318de8d7fSPeter Avalos int wait_status; /* Status returned by wait(). */ 56418de8d7fSPeter Avalos pid_t wait_pid; /* pid returned by wait(). */ 56518de8d7fSPeter Avalos int waiting_termination = 0; /* Have displayed waiting close message. */ 56618de8d7fSPeter Avalos u_int max_time_milliseconds; 56718de8d7fSPeter Avalos u_int previous_stdout_buffer_bytes; 56818de8d7fSPeter Avalos u_int stdout_buffer_bytes; 56918de8d7fSPeter Avalos int type; 57018de8d7fSPeter Avalos 57118de8d7fSPeter Avalos debug("Entering interactive session."); 57218de8d7fSPeter Avalos 57318de8d7fSPeter Avalos /* Initialize the SIGCHLD kludge. */ 57418de8d7fSPeter Avalos child_terminated = 0; 57518de8d7fSPeter Avalos mysignal(SIGCHLD, sigchld_handler); 57618de8d7fSPeter Avalos 57718de8d7fSPeter Avalos if (!use_privsep) { 57818de8d7fSPeter Avalos signal(SIGTERM, sigterm_handler); 57918de8d7fSPeter Avalos signal(SIGINT, sigterm_handler); 58018de8d7fSPeter Avalos signal(SIGQUIT, sigterm_handler); 58118de8d7fSPeter Avalos } 58218de8d7fSPeter Avalos 58318de8d7fSPeter Avalos /* Initialize our global variables. */ 58418de8d7fSPeter Avalos fdin = fdin_arg; 58518de8d7fSPeter Avalos fdout = fdout_arg; 58618de8d7fSPeter Avalos fderr = fderr_arg; 58718de8d7fSPeter Avalos 58818de8d7fSPeter Avalos /* nonblocking IO */ 58918de8d7fSPeter Avalos set_nonblock(fdin); 59018de8d7fSPeter Avalos set_nonblock(fdout); 59118de8d7fSPeter Avalos /* we don't have stderr for interactive terminal sessions, see below */ 59218de8d7fSPeter Avalos if (fderr != -1) 59318de8d7fSPeter Avalos set_nonblock(fderr); 59418de8d7fSPeter Avalos 59518de8d7fSPeter Avalos if (!(datafellows & SSH_BUG_IGNOREMSG) && isatty(fdin)) 59618de8d7fSPeter Avalos fdin_is_tty = 1; 59718de8d7fSPeter Avalos 59818de8d7fSPeter Avalos connection_in = packet_get_connection_in(); 59918de8d7fSPeter Avalos connection_out = packet_get_connection_out(); 60018de8d7fSPeter Avalos 60118de8d7fSPeter Avalos notify_setup(); 60218de8d7fSPeter Avalos 60318de8d7fSPeter Avalos previous_stdout_buffer_bytes = 0; 60418de8d7fSPeter Avalos 60518de8d7fSPeter Avalos /* Set approximate I/O buffer size. */ 60618de8d7fSPeter Avalos if (packet_is_interactive()) 60718de8d7fSPeter Avalos buffer_high = 4096; 60818de8d7fSPeter Avalos else 60918de8d7fSPeter Avalos buffer_high = 64 * 1024; 61018de8d7fSPeter Avalos 61118de8d7fSPeter Avalos #if 0 61218de8d7fSPeter Avalos /* Initialize max_fd to the maximum of the known file descriptors. */ 61318de8d7fSPeter Avalos max_fd = MAX(connection_in, connection_out); 61418de8d7fSPeter Avalos max_fd = MAX(max_fd, fdin); 61518de8d7fSPeter Avalos max_fd = MAX(max_fd, fdout); 61618de8d7fSPeter Avalos if (fderr != -1) 61718de8d7fSPeter Avalos max_fd = MAX(max_fd, fderr); 61818de8d7fSPeter Avalos #endif 61918de8d7fSPeter Avalos 62018de8d7fSPeter Avalos /* Initialize Initialize buffers. */ 62118de8d7fSPeter Avalos buffer_init(&stdin_buffer); 62218de8d7fSPeter Avalos buffer_init(&stdout_buffer); 62318de8d7fSPeter Avalos buffer_init(&stderr_buffer); 62418de8d7fSPeter Avalos 62518de8d7fSPeter Avalos /* 62618de8d7fSPeter Avalos * If we have no separate fderr (which is the case when we have a pty 62718de8d7fSPeter Avalos * - there we cannot make difference between data sent to stdout and 62818de8d7fSPeter Avalos * stderr), indicate that we have seen an EOF from stderr. This way 62918de8d7fSPeter Avalos * we don't need to check the descriptor everywhere. 63018de8d7fSPeter Avalos */ 63118de8d7fSPeter Avalos if (fderr == -1) 63218de8d7fSPeter Avalos fderr_eof = 1; 63318de8d7fSPeter Avalos 63418de8d7fSPeter Avalos server_init_dispatch(); 63518de8d7fSPeter Avalos 63618de8d7fSPeter Avalos /* Main loop of the server for the interactive session mode. */ 63718de8d7fSPeter Avalos for (;;) { 63818de8d7fSPeter Avalos 63918de8d7fSPeter Avalos /* Process buffered packets from the client. */ 64018de8d7fSPeter Avalos process_buffered_input_packets(); 64118de8d7fSPeter Avalos 64218de8d7fSPeter Avalos /* 64318de8d7fSPeter Avalos * If we have received eof, and there is no more pending 64418de8d7fSPeter Avalos * input data, cause a real eof by closing fdin. 64518de8d7fSPeter Avalos */ 64618de8d7fSPeter Avalos if (stdin_eof && fdin != -1 && buffer_len(&stdin_buffer) == 0) { 64718de8d7fSPeter Avalos if (fdin != fdout) 64818de8d7fSPeter Avalos close(fdin); 64918de8d7fSPeter Avalos else 65018de8d7fSPeter Avalos shutdown(fdin, SHUT_WR); /* We will no longer send. */ 65118de8d7fSPeter Avalos fdin = -1; 65218de8d7fSPeter Avalos } 65318de8d7fSPeter Avalos /* Make packets from buffered stderr data to send to the client. */ 65418de8d7fSPeter Avalos make_packets_from_stderr_data(); 65518de8d7fSPeter Avalos 65618de8d7fSPeter Avalos /* 65718de8d7fSPeter Avalos * Make packets from buffered stdout data to send to the 65818de8d7fSPeter Avalos * client. If there is very little to send, this arranges to 65918de8d7fSPeter Avalos * not send them now, but to wait a short while to see if we 66018de8d7fSPeter Avalos * are getting more data. This is necessary, as some systems 66118de8d7fSPeter Avalos * wake up readers from a pty after each separate character. 66218de8d7fSPeter Avalos */ 66318de8d7fSPeter Avalos max_time_milliseconds = 0; 66418de8d7fSPeter Avalos stdout_buffer_bytes = buffer_len(&stdout_buffer); 66518de8d7fSPeter Avalos if (stdout_buffer_bytes != 0 && stdout_buffer_bytes < 256 && 66618de8d7fSPeter Avalos stdout_buffer_bytes != previous_stdout_buffer_bytes) { 66718de8d7fSPeter Avalos /* try again after a while */ 66818de8d7fSPeter Avalos max_time_milliseconds = 10; 66918de8d7fSPeter Avalos } else { 67018de8d7fSPeter Avalos /* Send it now. */ 67118de8d7fSPeter Avalos make_packets_from_stdout_data(); 67218de8d7fSPeter Avalos } 67318de8d7fSPeter Avalos previous_stdout_buffer_bytes = buffer_len(&stdout_buffer); 67418de8d7fSPeter Avalos 67518de8d7fSPeter Avalos /* Send channel data to the client. */ 67618de8d7fSPeter Avalos if (packet_not_very_much_data_to_write()) 67718de8d7fSPeter Avalos channel_output_poll(); 67818de8d7fSPeter Avalos 67918de8d7fSPeter Avalos /* 68018de8d7fSPeter Avalos * Bail out of the loop if the program has closed its output 68118de8d7fSPeter Avalos * descriptors, and we have no more data to send to the 68218de8d7fSPeter Avalos * client, and there is no pending buffered data. 68318de8d7fSPeter Avalos */ 68418de8d7fSPeter Avalos if (fdout_eof && fderr_eof && !packet_have_data_to_write() && 68518de8d7fSPeter Avalos buffer_len(&stdout_buffer) == 0 && buffer_len(&stderr_buffer) == 0) { 68618de8d7fSPeter Avalos if (!channel_still_open()) 68718de8d7fSPeter Avalos break; 68818de8d7fSPeter Avalos if (!waiting_termination) { 68918de8d7fSPeter Avalos const char *s = "Waiting for forwarded connections to terminate...\r\n"; 69018de8d7fSPeter Avalos char *cp; 69118de8d7fSPeter Avalos waiting_termination = 1; 69218de8d7fSPeter Avalos buffer_append(&stderr_buffer, s, strlen(s)); 69318de8d7fSPeter Avalos 69418de8d7fSPeter Avalos /* Display list of open channels. */ 69518de8d7fSPeter Avalos cp = channel_open_message(); 69618de8d7fSPeter Avalos buffer_append(&stderr_buffer, cp, strlen(cp)); 69718de8d7fSPeter Avalos xfree(cp); 69818de8d7fSPeter Avalos } 69918de8d7fSPeter Avalos } 70018de8d7fSPeter Avalos max_fd = MAX(connection_in, connection_out); 70118de8d7fSPeter Avalos max_fd = MAX(max_fd, fdin); 70218de8d7fSPeter Avalos max_fd = MAX(max_fd, fdout); 70318de8d7fSPeter Avalos max_fd = MAX(max_fd, fderr); 70418de8d7fSPeter Avalos max_fd = MAX(max_fd, notify_pipe[0]); 70518de8d7fSPeter Avalos 70618de8d7fSPeter Avalos /* Sleep in select() until we can do something. */ 70718de8d7fSPeter Avalos wait_until_can_do_something(&readset, &writeset, &max_fd, 70818de8d7fSPeter Avalos &nalloc, max_time_milliseconds); 70918de8d7fSPeter Avalos 71018de8d7fSPeter Avalos if (received_sigterm) { 71118de8d7fSPeter Avalos logit("Exiting on signal %d", received_sigterm); 71218de8d7fSPeter Avalos /* Clean up sessions, utmp, etc. */ 71318de8d7fSPeter Avalos cleanup_exit(255); 71418de8d7fSPeter Avalos } 71518de8d7fSPeter Avalos 71618de8d7fSPeter Avalos /* Process any channel events. */ 71718de8d7fSPeter Avalos channel_after_select(readset, writeset); 71818de8d7fSPeter Avalos 71918de8d7fSPeter Avalos /* Process input from the client and from program stdout/stderr. */ 72018de8d7fSPeter Avalos process_input(readset); 72118de8d7fSPeter Avalos 72218de8d7fSPeter Avalos /* Process output to the client and to program stdin. */ 72318de8d7fSPeter Avalos process_output(writeset); 72418de8d7fSPeter Avalos } 72518de8d7fSPeter Avalos if (readset) 72618de8d7fSPeter Avalos xfree(readset); 72718de8d7fSPeter Avalos if (writeset) 72818de8d7fSPeter Avalos xfree(writeset); 72918de8d7fSPeter Avalos 73018de8d7fSPeter Avalos /* Cleanup and termination code. */ 73118de8d7fSPeter Avalos 73218de8d7fSPeter Avalos /* Wait until all output has been sent to the client. */ 73318de8d7fSPeter Avalos drain_output(); 73418de8d7fSPeter Avalos 73518de8d7fSPeter Avalos debug("End of interactive session; stdin %ld, stdout (read %ld, sent %ld), stderr %ld bytes.", 73618de8d7fSPeter Avalos stdin_bytes, fdout_bytes, stdout_bytes, stderr_bytes); 73718de8d7fSPeter Avalos 73818de8d7fSPeter Avalos /* Free and clear the buffers. */ 73918de8d7fSPeter Avalos buffer_free(&stdin_buffer); 74018de8d7fSPeter Avalos buffer_free(&stdout_buffer); 74118de8d7fSPeter Avalos buffer_free(&stderr_buffer); 74218de8d7fSPeter Avalos 74318de8d7fSPeter Avalos /* Close the file descriptors. */ 74418de8d7fSPeter Avalos if (fdout != -1) 74518de8d7fSPeter Avalos close(fdout); 74618de8d7fSPeter Avalos fdout = -1; 74718de8d7fSPeter Avalos fdout_eof = 1; 74818de8d7fSPeter Avalos if (fderr != -1) 74918de8d7fSPeter Avalos close(fderr); 75018de8d7fSPeter Avalos fderr = -1; 75118de8d7fSPeter Avalos fderr_eof = 1; 75218de8d7fSPeter Avalos if (fdin != -1) 75318de8d7fSPeter Avalos close(fdin); 75418de8d7fSPeter Avalos fdin = -1; 75518de8d7fSPeter Avalos 75618de8d7fSPeter Avalos channel_free_all(); 75718de8d7fSPeter Avalos 75818de8d7fSPeter Avalos /* We no longer want our SIGCHLD handler to be called. */ 75918de8d7fSPeter Avalos mysignal(SIGCHLD, SIG_DFL); 76018de8d7fSPeter Avalos 76118de8d7fSPeter Avalos while ((wait_pid = waitpid(-1, &wait_status, 0)) < 0) 76218de8d7fSPeter Avalos if (errno != EINTR) 76318de8d7fSPeter Avalos packet_disconnect("wait: %.100s", strerror(errno)); 76418de8d7fSPeter Avalos if (wait_pid != pid) 76518de8d7fSPeter Avalos error("Strange, wait returned pid %ld, expected %ld", 76618de8d7fSPeter Avalos (long)wait_pid, (long)pid); 76718de8d7fSPeter Avalos 76818de8d7fSPeter Avalos /* Check if it exited normally. */ 76918de8d7fSPeter Avalos if (WIFEXITED(wait_status)) { 77018de8d7fSPeter Avalos /* Yes, normal exit. Get exit status and send it to the client. */ 77118de8d7fSPeter Avalos debug("Command exited with status %d.", WEXITSTATUS(wait_status)); 77218de8d7fSPeter Avalos packet_start(SSH_SMSG_EXITSTATUS); 77318de8d7fSPeter Avalos packet_put_int(WEXITSTATUS(wait_status)); 77418de8d7fSPeter Avalos packet_send(); 77518de8d7fSPeter Avalos packet_write_wait(); 77618de8d7fSPeter Avalos 77718de8d7fSPeter Avalos /* 77818de8d7fSPeter Avalos * Wait for exit confirmation. Note that there might be 77918de8d7fSPeter Avalos * other packets coming before it; however, the program has 78018de8d7fSPeter Avalos * already died so we just ignore them. The client is 78118de8d7fSPeter Avalos * supposed to respond with the confirmation when it receives 78218de8d7fSPeter Avalos * the exit status. 78318de8d7fSPeter Avalos */ 78418de8d7fSPeter Avalos do { 78518de8d7fSPeter Avalos type = packet_read(); 78618de8d7fSPeter Avalos } 78718de8d7fSPeter Avalos while (type != SSH_CMSG_EXIT_CONFIRMATION); 78818de8d7fSPeter Avalos 78918de8d7fSPeter Avalos debug("Received exit confirmation."); 79018de8d7fSPeter Avalos return; 79118de8d7fSPeter Avalos } 79218de8d7fSPeter Avalos /* Check if the program terminated due to a signal. */ 79318de8d7fSPeter Avalos if (WIFSIGNALED(wait_status)) 79418de8d7fSPeter Avalos packet_disconnect("Command terminated on signal %d.", 79518de8d7fSPeter Avalos WTERMSIG(wait_status)); 79618de8d7fSPeter Avalos 79718de8d7fSPeter Avalos /* Some weird exit cause. Just exit. */ 79818de8d7fSPeter Avalos packet_disconnect("wait returned status %04x.", wait_status); 79918de8d7fSPeter Avalos /* NOTREACHED */ 80018de8d7fSPeter Avalos } 80118de8d7fSPeter Avalos 80218de8d7fSPeter Avalos static void 80318de8d7fSPeter Avalos collect_children(void) 80418de8d7fSPeter Avalos { 80518de8d7fSPeter Avalos pid_t pid; 80618de8d7fSPeter Avalos sigset_t oset, nset; 80718de8d7fSPeter Avalos int status; 80818de8d7fSPeter Avalos 80918de8d7fSPeter Avalos /* block SIGCHLD while we check for dead children */ 81018de8d7fSPeter Avalos sigemptyset(&nset); 81118de8d7fSPeter Avalos sigaddset(&nset, SIGCHLD); 81218de8d7fSPeter Avalos sigprocmask(SIG_BLOCK, &nset, &oset); 81318de8d7fSPeter Avalos if (child_terminated) { 81418de8d7fSPeter Avalos debug("Received SIGCHLD."); 81518de8d7fSPeter Avalos while ((pid = waitpid(-1, &status, WNOHANG)) > 0 || 81618de8d7fSPeter Avalos (pid < 0 && errno == EINTR)) 81718de8d7fSPeter Avalos if (pid > 0) 81818de8d7fSPeter Avalos session_close_by_pid(pid, status); 81918de8d7fSPeter Avalos child_terminated = 0; 82018de8d7fSPeter Avalos } 82118de8d7fSPeter Avalos sigprocmask(SIG_SETMASK, &oset, NULL); 82218de8d7fSPeter Avalos } 82318de8d7fSPeter Avalos 82418de8d7fSPeter Avalos void 82518de8d7fSPeter Avalos server_loop2(Authctxt *authctxt) 82618de8d7fSPeter Avalos { 82718de8d7fSPeter Avalos fd_set *readset = NULL, *writeset = NULL; 82818de8d7fSPeter Avalos int rekeying = 0, max_fd, nalloc = 0; 82918de8d7fSPeter Avalos 83018de8d7fSPeter Avalos debug("Entering interactive session for SSH2."); 83118de8d7fSPeter Avalos 83218de8d7fSPeter Avalos mysignal(SIGCHLD, sigchld_handler); 83318de8d7fSPeter Avalos child_terminated = 0; 83418de8d7fSPeter Avalos connection_in = packet_get_connection_in(); 83518de8d7fSPeter Avalos connection_out = packet_get_connection_out(); 83618de8d7fSPeter Avalos 83718de8d7fSPeter Avalos if (!use_privsep) { 83818de8d7fSPeter Avalos signal(SIGTERM, sigterm_handler); 83918de8d7fSPeter Avalos signal(SIGINT, sigterm_handler); 84018de8d7fSPeter Avalos signal(SIGQUIT, sigterm_handler); 84118de8d7fSPeter Avalos } 84218de8d7fSPeter Avalos 84318de8d7fSPeter Avalos notify_setup(); 84418de8d7fSPeter Avalos 84518de8d7fSPeter Avalos max_fd = MAX(connection_in, connection_out); 84618de8d7fSPeter Avalos max_fd = MAX(max_fd, notify_pipe[0]); 84718de8d7fSPeter Avalos 84818de8d7fSPeter Avalos server_init_dispatch(); 84918de8d7fSPeter Avalos 85018de8d7fSPeter Avalos for (;;) { 85118de8d7fSPeter Avalos process_buffered_input_packets(); 85218de8d7fSPeter Avalos 85318de8d7fSPeter Avalos rekeying = (xxx_kex != NULL && !xxx_kex->done); 85418de8d7fSPeter Avalos 85518de8d7fSPeter Avalos if (!rekeying && packet_not_very_much_data_to_write()) 85618de8d7fSPeter Avalos channel_output_poll(); 85718de8d7fSPeter Avalos wait_until_can_do_something(&readset, &writeset, &max_fd, 85818de8d7fSPeter Avalos &nalloc, 0); 85918de8d7fSPeter Avalos 86018de8d7fSPeter Avalos if (received_sigterm) { 86118de8d7fSPeter Avalos logit("Exiting on signal %d", received_sigterm); 86218de8d7fSPeter Avalos /* Clean up sessions, utmp, etc. */ 86318de8d7fSPeter Avalos cleanup_exit(255); 86418de8d7fSPeter Avalos } 86518de8d7fSPeter Avalos 86618de8d7fSPeter Avalos collect_children(); 86718de8d7fSPeter Avalos if (!rekeying) { 86818de8d7fSPeter Avalos channel_after_select(readset, writeset); 86918de8d7fSPeter Avalos if (packet_need_rekeying()) { 87018de8d7fSPeter Avalos debug("need rekeying"); 87118de8d7fSPeter Avalos xxx_kex->done = 0; 87218de8d7fSPeter Avalos kex_send_kexinit(xxx_kex); 87318de8d7fSPeter Avalos } 87418de8d7fSPeter Avalos } 87518de8d7fSPeter Avalos process_input(readset); 87618de8d7fSPeter Avalos if (connection_closed) 87718de8d7fSPeter Avalos break; 87818de8d7fSPeter Avalos process_output(writeset); 87918de8d7fSPeter Avalos } 88018de8d7fSPeter Avalos collect_children(); 88118de8d7fSPeter Avalos 88218de8d7fSPeter Avalos if (readset) 88318de8d7fSPeter Avalos xfree(readset); 88418de8d7fSPeter Avalos if (writeset) 88518de8d7fSPeter Avalos xfree(writeset); 88618de8d7fSPeter Avalos 88718de8d7fSPeter Avalos /* free all channels, no more reads and writes */ 88818de8d7fSPeter Avalos channel_free_all(); 88918de8d7fSPeter Avalos 89018de8d7fSPeter Avalos /* free remaining sessions, e.g. remove wtmp entries */ 89118de8d7fSPeter Avalos session_destroy_all(NULL); 89218de8d7fSPeter Avalos } 89318de8d7fSPeter Avalos 89418de8d7fSPeter Avalos static void 89518de8d7fSPeter Avalos server_input_keep_alive(int type, u_int32_t seq, void *ctxt) 89618de8d7fSPeter Avalos { 89718de8d7fSPeter Avalos debug("Got %d/%u for keepalive", type, seq); 89818de8d7fSPeter Avalos /* 89918de8d7fSPeter Avalos * reset timeout, since we got a sane answer from the client. 90018de8d7fSPeter Avalos * even if this was generated by something other than 90118de8d7fSPeter Avalos * the bogus CHANNEL_REQUEST we send for keepalives. 90218de8d7fSPeter Avalos */ 90340c002afSPeter Avalos packet_set_alive_timeouts(0); 90418de8d7fSPeter Avalos } 90518de8d7fSPeter Avalos 90618de8d7fSPeter Avalos static void 90718de8d7fSPeter Avalos server_input_stdin_data(int type, u_int32_t seq, void *ctxt) 90818de8d7fSPeter Avalos { 90918de8d7fSPeter Avalos char *data; 91018de8d7fSPeter Avalos u_int data_len; 91118de8d7fSPeter Avalos 91218de8d7fSPeter Avalos /* Stdin data from the client. Append it to the buffer. */ 91318de8d7fSPeter Avalos /* Ignore any data if the client has closed stdin. */ 91418de8d7fSPeter Avalos if (fdin == -1) 91518de8d7fSPeter Avalos return; 91618de8d7fSPeter Avalos data = packet_get_string(&data_len); 91718de8d7fSPeter Avalos packet_check_eom(); 91818de8d7fSPeter Avalos buffer_append(&stdin_buffer, data, data_len); 91918de8d7fSPeter Avalos memset(data, 0, data_len); 92018de8d7fSPeter Avalos xfree(data); 92118de8d7fSPeter Avalos } 92218de8d7fSPeter Avalos 92318de8d7fSPeter Avalos static void 92418de8d7fSPeter Avalos server_input_eof(int type, u_int32_t seq, void *ctxt) 92518de8d7fSPeter Avalos { 92618de8d7fSPeter Avalos /* 92718de8d7fSPeter Avalos * Eof from the client. The stdin descriptor to the 92818de8d7fSPeter Avalos * program will be closed when all buffered data has 92918de8d7fSPeter Avalos * drained. 93018de8d7fSPeter Avalos */ 93118de8d7fSPeter Avalos debug("EOF received for stdin."); 93218de8d7fSPeter Avalos packet_check_eom(); 93318de8d7fSPeter Avalos stdin_eof = 1; 93418de8d7fSPeter Avalos } 93518de8d7fSPeter Avalos 93618de8d7fSPeter Avalos static void 93718de8d7fSPeter Avalos server_input_window_size(int type, u_int32_t seq, void *ctxt) 93818de8d7fSPeter Avalos { 93918de8d7fSPeter Avalos u_int row = packet_get_int(); 94018de8d7fSPeter Avalos u_int col = packet_get_int(); 94118de8d7fSPeter Avalos u_int xpixel = packet_get_int(); 94218de8d7fSPeter Avalos u_int ypixel = packet_get_int(); 94318de8d7fSPeter Avalos 94418de8d7fSPeter Avalos debug("Window change received."); 94518de8d7fSPeter Avalos packet_check_eom(); 94618de8d7fSPeter Avalos if (fdin != -1) 94718de8d7fSPeter Avalos pty_change_window_size(fdin, row, col, xpixel, ypixel); 94818de8d7fSPeter Avalos } 94918de8d7fSPeter Avalos 95018de8d7fSPeter Avalos static Channel * 95118de8d7fSPeter Avalos server_request_direct_tcpip(void) 95218de8d7fSPeter Avalos { 95318de8d7fSPeter Avalos Channel *c; 95418de8d7fSPeter Avalos char *target, *originator; 955cb5eb4f1SPeter Avalos u_short target_port, originator_port; 95618de8d7fSPeter Avalos 95718de8d7fSPeter Avalos target = packet_get_string(NULL); 95818de8d7fSPeter Avalos target_port = packet_get_int(); 95918de8d7fSPeter Avalos originator = packet_get_string(NULL); 96018de8d7fSPeter Avalos originator_port = packet_get_int(); 96118de8d7fSPeter Avalos packet_check_eom(); 96218de8d7fSPeter Avalos 96318de8d7fSPeter Avalos debug("server_request_direct_tcpip: originator %s port %d, target %s " 96418de8d7fSPeter Avalos "port %d", originator, originator_port, target, target_port); 96518de8d7fSPeter Avalos 96618de8d7fSPeter Avalos /* XXX check permission */ 96718de8d7fSPeter Avalos c = channel_connect_to(target, target_port, 96818de8d7fSPeter Avalos "direct-tcpip", "direct-tcpip"); 96918de8d7fSPeter Avalos 97018de8d7fSPeter Avalos xfree(originator); 97118de8d7fSPeter Avalos xfree(target); 97218de8d7fSPeter Avalos 97318de8d7fSPeter Avalos return c; 97418de8d7fSPeter Avalos } 97518de8d7fSPeter Avalos 97618de8d7fSPeter Avalos static Channel * 97718de8d7fSPeter Avalos server_request_tun(void) 97818de8d7fSPeter Avalos { 97918de8d7fSPeter Avalos Channel *c = NULL; 98018de8d7fSPeter Avalos int mode, tun; 98118de8d7fSPeter Avalos int sock; 98218de8d7fSPeter Avalos 98318de8d7fSPeter Avalos mode = packet_get_int(); 98418de8d7fSPeter Avalos switch (mode) { 98518de8d7fSPeter Avalos case SSH_TUNMODE_POINTOPOINT: 98618de8d7fSPeter Avalos case SSH_TUNMODE_ETHERNET: 98718de8d7fSPeter Avalos break; 98818de8d7fSPeter Avalos default: 98918de8d7fSPeter Avalos packet_send_debug("Unsupported tunnel device mode."); 99018de8d7fSPeter Avalos return NULL; 99118de8d7fSPeter Avalos } 99218de8d7fSPeter Avalos if ((options.permit_tun & mode) == 0) { 99318de8d7fSPeter Avalos packet_send_debug("Server has rejected tunnel device " 99418de8d7fSPeter Avalos "forwarding"); 99518de8d7fSPeter Avalos return NULL; 99618de8d7fSPeter Avalos } 99718de8d7fSPeter Avalos 99818de8d7fSPeter Avalos tun = packet_get_int(); 99918de8d7fSPeter Avalos if (forced_tun_device != -1) { 100018de8d7fSPeter Avalos if (tun != SSH_TUNID_ANY && forced_tun_device != tun) 100118de8d7fSPeter Avalos goto done; 100218de8d7fSPeter Avalos tun = forced_tun_device; 100318de8d7fSPeter Avalos } 100418de8d7fSPeter Avalos sock = tun_open(tun, mode); 100518de8d7fSPeter Avalos if (sock < 0) 100618de8d7fSPeter Avalos goto done; 100718de8d7fSPeter Avalos c = channel_new("tun", SSH_CHANNEL_OPEN, sock, sock, -1, 100818de8d7fSPeter Avalos CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, "tun", 1); 100918de8d7fSPeter Avalos c->datagram = 1; 101018de8d7fSPeter Avalos #if defined(SSH_TUN_FILTER) 101118de8d7fSPeter Avalos if (mode == SSH_TUNMODE_POINTOPOINT) 101218de8d7fSPeter Avalos channel_register_filter(c->self, sys_tun_infilter, 101318de8d7fSPeter Avalos sys_tun_outfilter, NULL, NULL); 101418de8d7fSPeter Avalos #endif 101518de8d7fSPeter Avalos 101618de8d7fSPeter Avalos done: 101718de8d7fSPeter Avalos if (c == NULL) 101818de8d7fSPeter Avalos packet_send_debug("Failed to open the tunnel device."); 101918de8d7fSPeter Avalos return c; 102018de8d7fSPeter Avalos } 102118de8d7fSPeter Avalos 102218de8d7fSPeter Avalos static Channel * 102318de8d7fSPeter Avalos server_request_session(void) 102418de8d7fSPeter Avalos { 102518de8d7fSPeter Avalos Channel *c; 102618de8d7fSPeter Avalos 102718de8d7fSPeter Avalos debug("input_session_request"); 102818de8d7fSPeter Avalos packet_check_eom(); 102918de8d7fSPeter Avalos 103018de8d7fSPeter Avalos if (no_more_sessions) { 103118de8d7fSPeter Avalos packet_disconnect("Possible attack: attempt to open a session " 103218de8d7fSPeter Avalos "after additional sessions disabled"); 103318de8d7fSPeter Avalos } 103418de8d7fSPeter Avalos 103518de8d7fSPeter Avalos /* 103618de8d7fSPeter Avalos * A server session has no fd to read or write until a 103718de8d7fSPeter Avalos * CHANNEL_REQUEST for a shell is made, so we set the type to 103818de8d7fSPeter Avalos * SSH_CHANNEL_LARVAL. Additionally, a callback for handling all 103918de8d7fSPeter Avalos * CHANNEL_REQUEST messages is registered. 104018de8d7fSPeter Avalos */ 104118de8d7fSPeter Avalos c = channel_new("session", SSH_CHANNEL_LARVAL, 104218de8d7fSPeter Avalos -1, -1, -1, /*window size*/0, CHAN_SES_PACKET_DEFAULT, 104318de8d7fSPeter Avalos 0, "server-session", 1); 104418de8d7fSPeter Avalos if (session_open(the_authctxt, c->self) != 1) { 104518de8d7fSPeter Avalos debug("session open failed, free channel %d", c->self); 104618de8d7fSPeter Avalos channel_free(c); 104718de8d7fSPeter Avalos return NULL; 104818de8d7fSPeter Avalos } 104918de8d7fSPeter Avalos channel_register_cleanup(c->self, session_close_by_channel, 0); 105018de8d7fSPeter Avalos return c; 105118de8d7fSPeter Avalos } 105218de8d7fSPeter Avalos 105318de8d7fSPeter Avalos static void 105418de8d7fSPeter Avalos server_input_channel_open(int type, u_int32_t seq, void *ctxt) 105518de8d7fSPeter Avalos { 105618de8d7fSPeter Avalos Channel *c = NULL; 105718de8d7fSPeter Avalos char *ctype; 105818de8d7fSPeter Avalos int rchan; 105918de8d7fSPeter Avalos u_int rmaxpack, rwindow, len; 106018de8d7fSPeter Avalos 106118de8d7fSPeter Avalos ctype = packet_get_string(&len); 106218de8d7fSPeter Avalos rchan = packet_get_int(); 106318de8d7fSPeter Avalos rwindow = packet_get_int(); 106418de8d7fSPeter Avalos rmaxpack = packet_get_int(); 106518de8d7fSPeter Avalos 106618de8d7fSPeter Avalos debug("server_input_channel_open: ctype %s rchan %d win %d max %d", 106718de8d7fSPeter Avalos ctype, rchan, rwindow, rmaxpack); 106818de8d7fSPeter Avalos 106918de8d7fSPeter Avalos if (strcmp(ctype, "session") == 0) { 107018de8d7fSPeter Avalos c = server_request_session(); 107118de8d7fSPeter Avalos } else if (strcmp(ctype, "direct-tcpip") == 0) { 107218de8d7fSPeter Avalos c = server_request_direct_tcpip(); 107318de8d7fSPeter Avalos } else if (strcmp(ctype, "tun@openssh.com") == 0) { 107418de8d7fSPeter Avalos c = server_request_tun(); 107518de8d7fSPeter Avalos } 107618de8d7fSPeter Avalos if (c != NULL) { 107718de8d7fSPeter Avalos debug("server_input_channel_open: confirm %s", ctype); 107818de8d7fSPeter Avalos c->remote_id = rchan; 107918de8d7fSPeter Avalos c->remote_window = rwindow; 108018de8d7fSPeter Avalos c->remote_maxpacket = rmaxpack; 108118de8d7fSPeter Avalos if (c->type != SSH_CHANNEL_CONNECTING) { 108218de8d7fSPeter Avalos packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION); 108318de8d7fSPeter Avalos packet_put_int(c->remote_id); 108418de8d7fSPeter Avalos packet_put_int(c->self); 108518de8d7fSPeter Avalos packet_put_int(c->local_window); 108618de8d7fSPeter Avalos packet_put_int(c->local_maxpacket); 108718de8d7fSPeter Avalos packet_send(); 108818de8d7fSPeter Avalos } 108918de8d7fSPeter Avalos } else { 109018de8d7fSPeter Avalos debug("server_input_channel_open: failure %s", ctype); 109118de8d7fSPeter Avalos packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE); 109218de8d7fSPeter Avalos packet_put_int(rchan); 109318de8d7fSPeter Avalos packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED); 109418de8d7fSPeter Avalos if (!(datafellows & SSH_BUG_OPENFAILURE)) { 109518de8d7fSPeter Avalos packet_put_cstring("open failed"); 109618de8d7fSPeter Avalos packet_put_cstring(""); 109718de8d7fSPeter Avalos } 109818de8d7fSPeter Avalos packet_send(); 109918de8d7fSPeter Avalos } 110018de8d7fSPeter Avalos xfree(ctype); 110118de8d7fSPeter Avalos } 110218de8d7fSPeter Avalos 110318de8d7fSPeter Avalos static void 110418de8d7fSPeter Avalos server_input_global_request(int type, u_int32_t seq, void *ctxt) 110518de8d7fSPeter Avalos { 110618de8d7fSPeter Avalos char *rtype; 110718de8d7fSPeter Avalos int want_reply; 1108cb5eb4f1SPeter Avalos int success = 0, allocated_listen_port = 0; 110918de8d7fSPeter Avalos 111018de8d7fSPeter Avalos rtype = packet_get_string(NULL); 111118de8d7fSPeter Avalos want_reply = packet_get_char(); 111218de8d7fSPeter Avalos debug("server_input_global_request: rtype %s want_reply %d", rtype, want_reply); 111318de8d7fSPeter Avalos 111418de8d7fSPeter Avalos /* -R style forwarding */ 111518de8d7fSPeter Avalos if (strcmp(rtype, "tcpip-forward") == 0) { 111618de8d7fSPeter Avalos struct passwd *pw; 111718de8d7fSPeter Avalos char *listen_address; 111818de8d7fSPeter Avalos u_short listen_port; 111918de8d7fSPeter Avalos 112018de8d7fSPeter Avalos pw = the_authctxt->pw; 112118de8d7fSPeter Avalos if (pw == NULL || !the_authctxt->valid) 112218de8d7fSPeter Avalos fatal("server_input_global_request: no/invalid user"); 112318de8d7fSPeter Avalos listen_address = packet_get_string(NULL); 112418de8d7fSPeter Avalos listen_port = (u_short)packet_get_int(); 112518de8d7fSPeter Avalos debug("server_input_global_request: tcpip-forward listen %s port %d", 112618de8d7fSPeter Avalos listen_address, listen_port); 112718de8d7fSPeter Avalos 112818de8d7fSPeter Avalos /* check permissions */ 112918de8d7fSPeter Avalos if (!options.allow_tcp_forwarding || 1130cb5eb4f1SPeter Avalos no_port_forwarding_flag || 1131cb5eb4f1SPeter Avalos (!want_reply && listen_port == 0) 113218de8d7fSPeter Avalos #ifndef NO_IPPORT_RESERVED_CONCEPT 113340c002afSPeter Avalos || (listen_port != 0 && listen_port < IPPORT_RESERVED && 113440c002afSPeter Avalos pw->pw_uid != 0) 113518de8d7fSPeter Avalos #endif 113618de8d7fSPeter Avalos ) { 113718de8d7fSPeter Avalos success = 0; 113818de8d7fSPeter Avalos packet_send_debug("Server has disabled port forwarding."); 113918de8d7fSPeter Avalos } else { 114018de8d7fSPeter Avalos /* Start listening on the port */ 114118de8d7fSPeter Avalos success = channel_setup_remote_fwd_listener( 1142cb5eb4f1SPeter Avalos listen_address, listen_port, 1143cb5eb4f1SPeter Avalos &allocated_listen_port, options.gateway_ports); 114418de8d7fSPeter Avalos } 114518de8d7fSPeter Avalos xfree(listen_address); 114618de8d7fSPeter Avalos } else if (strcmp(rtype, "cancel-tcpip-forward") == 0) { 114718de8d7fSPeter Avalos char *cancel_address; 114818de8d7fSPeter Avalos u_short cancel_port; 114918de8d7fSPeter Avalos 115018de8d7fSPeter Avalos cancel_address = packet_get_string(NULL); 115118de8d7fSPeter Avalos cancel_port = (u_short)packet_get_int(); 115218de8d7fSPeter Avalos debug("%s: cancel-tcpip-forward addr %s port %d", __func__, 115318de8d7fSPeter Avalos cancel_address, cancel_port); 115418de8d7fSPeter Avalos 115518de8d7fSPeter Avalos success = channel_cancel_rport_listener(cancel_address, 115618de8d7fSPeter Avalos cancel_port); 115718de8d7fSPeter Avalos xfree(cancel_address); 115818de8d7fSPeter Avalos } else if (strcmp(rtype, "no-more-sessions@openssh.com") == 0) { 115918de8d7fSPeter Avalos no_more_sessions = 1; 116018de8d7fSPeter Avalos success = 1; 116118de8d7fSPeter Avalos } 116218de8d7fSPeter Avalos if (want_reply) { 116318de8d7fSPeter Avalos packet_start(success ? 116418de8d7fSPeter Avalos SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE); 1165cb5eb4f1SPeter Avalos if (success && allocated_listen_port > 0) 1166cb5eb4f1SPeter Avalos packet_put_int(allocated_listen_port); 116718de8d7fSPeter Avalos packet_send(); 116818de8d7fSPeter Avalos packet_write_wait(); 116918de8d7fSPeter Avalos } 117018de8d7fSPeter Avalos xfree(rtype); 117118de8d7fSPeter Avalos } 117218de8d7fSPeter Avalos 117318de8d7fSPeter Avalos static void 117418de8d7fSPeter Avalos server_input_channel_req(int type, u_int32_t seq, void *ctxt) 117518de8d7fSPeter Avalos { 117618de8d7fSPeter Avalos Channel *c; 117718de8d7fSPeter Avalos int id, reply, success = 0; 117818de8d7fSPeter Avalos char *rtype; 117918de8d7fSPeter Avalos 118018de8d7fSPeter Avalos id = packet_get_int(); 118118de8d7fSPeter Avalos rtype = packet_get_string(NULL); 118218de8d7fSPeter Avalos reply = packet_get_char(); 118318de8d7fSPeter Avalos 118418de8d7fSPeter Avalos debug("server_input_channel_req: channel %d request %s reply %d", 118518de8d7fSPeter Avalos id, rtype, reply); 118618de8d7fSPeter Avalos 118718de8d7fSPeter Avalos if ((c = channel_lookup(id)) == NULL) 118818de8d7fSPeter Avalos packet_disconnect("server_input_channel_req: " 118918de8d7fSPeter Avalos "unknown channel %d", id); 119018de8d7fSPeter Avalos if (!strcmp(rtype, "eow@openssh.com")) { 119118de8d7fSPeter Avalos packet_check_eom(); 119218de8d7fSPeter Avalos chan_rcvd_eow(c); 119318de8d7fSPeter Avalos } else if ((c->type == SSH_CHANNEL_LARVAL || 119418de8d7fSPeter Avalos c->type == SSH_CHANNEL_OPEN) && strcmp(c->ctype, "session") == 0) 119518de8d7fSPeter Avalos success = session_input_channel_req(c, rtype); 119618de8d7fSPeter Avalos if (reply) { 119718de8d7fSPeter Avalos packet_start(success ? 119818de8d7fSPeter Avalos SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE); 119918de8d7fSPeter Avalos packet_put_int(c->remote_id); 120018de8d7fSPeter Avalos packet_send(); 120118de8d7fSPeter Avalos } 120218de8d7fSPeter Avalos xfree(rtype); 120318de8d7fSPeter Avalos } 120418de8d7fSPeter Avalos 120518de8d7fSPeter Avalos static void 120618de8d7fSPeter Avalos server_init_dispatch_20(void) 120718de8d7fSPeter Avalos { 120818de8d7fSPeter Avalos debug("server_init_dispatch_20"); 120918de8d7fSPeter Avalos dispatch_init(&dispatch_protocol_error); 121018de8d7fSPeter Avalos dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose); 121118de8d7fSPeter Avalos dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data); 121218de8d7fSPeter Avalos dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof); 121318de8d7fSPeter Avalos dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data); 121418de8d7fSPeter Avalos dispatch_set(SSH2_MSG_CHANNEL_OPEN, &server_input_channel_open); 121518de8d7fSPeter Avalos dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation); 121618de8d7fSPeter Avalos dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure); 121718de8d7fSPeter Avalos dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &server_input_channel_req); 121818de8d7fSPeter Avalos dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust); 121918de8d7fSPeter Avalos dispatch_set(SSH2_MSG_GLOBAL_REQUEST, &server_input_global_request); 122018de8d7fSPeter Avalos /* client_alive */ 1221cb5eb4f1SPeter Avalos dispatch_set(SSH2_MSG_CHANNEL_SUCCESS, &server_input_keep_alive); 1222cb5eb4f1SPeter Avalos dispatch_set(SSH2_MSG_CHANNEL_FAILURE, &server_input_keep_alive); 122318de8d7fSPeter Avalos dispatch_set(SSH2_MSG_REQUEST_SUCCESS, &server_input_keep_alive); 122418de8d7fSPeter Avalos dispatch_set(SSH2_MSG_REQUEST_FAILURE, &server_input_keep_alive); 122518de8d7fSPeter Avalos /* rekeying */ 122618de8d7fSPeter Avalos dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit); 122718de8d7fSPeter Avalos } 122818de8d7fSPeter Avalos static void 122918de8d7fSPeter Avalos server_init_dispatch_13(void) 123018de8d7fSPeter Avalos { 123118de8d7fSPeter Avalos debug("server_init_dispatch_13"); 123218de8d7fSPeter Avalos dispatch_init(NULL); 123318de8d7fSPeter Avalos dispatch_set(SSH_CMSG_EOF, &server_input_eof); 123418de8d7fSPeter Avalos dispatch_set(SSH_CMSG_STDIN_DATA, &server_input_stdin_data); 123518de8d7fSPeter Avalos dispatch_set(SSH_CMSG_WINDOW_SIZE, &server_input_window_size); 123618de8d7fSPeter Avalos dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close); 123718de8d7fSPeter Avalos dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation); 123818de8d7fSPeter Avalos dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data); 123918de8d7fSPeter Avalos dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation); 124018de8d7fSPeter Avalos dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure); 124118de8d7fSPeter Avalos dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open); 124218de8d7fSPeter Avalos } 124318de8d7fSPeter Avalos static void 124418de8d7fSPeter Avalos server_init_dispatch_15(void) 124518de8d7fSPeter Avalos { 124618de8d7fSPeter Avalos server_init_dispatch_13(); 124718de8d7fSPeter Avalos debug("server_init_dispatch_15"); 124818de8d7fSPeter Avalos dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof); 124918de8d7fSPeter Avalos dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_oclose); 125018de8d7fSPeter Avalos } 125118de8d7fSPeter Avalos static void 125218de8d7fSPeter Avalos server_init_dispatch(void) 125318de8d7fSPeter Avalos { 125418de8d7fSPeter Avalos if (compat20) 125518de8d7fSPeter Avalos server_init_dispatch_20(); 125618de8d7fSPeter Avalos else if (compat13) 125718de8d7fSPeter Avalos server_init_dispatch_13(); 125818de8d7fSPeter Avalos else 125918de8d7fSPeter Avalos server_init_dispatch_15(); 126018de8d7fSPeter Avalos } 1261