1*e9778795SPeter Avalos /* $OpenBSD: serverloop.c,v 1.184 2016/03/07 19:02:43 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 40*e9778795SPeter Avalos #include <sys/param.h> /* MIN MAX */ 4118de8d7fSPeter Avalos #include <sys/types.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" 6436e94dc5SPeter Avalos #include "misc.h" 6518de8d7fSPeter Avalos #include "servconf.h" 6618de8d7fSPeter Avalos #include "canohost.h" 6718de8d7fSPeter Avalos #include "sshpty.h" 6818de8d7fSPeter Avalos #include "channels.h" 6918de8d7fSPeter Avalos #include "compat.h" 7018de8d7fSPeter Avalos #include "ssh1.h" 7118de8d7fSPeter Avalos #include "ssh2.h" 7218de8d7fSPeter Avalos #include "key.h" 7318de8d7fSPeter Avalos #include "cipher.h" 7418de8d7fSPeter Avalos #include "kex.h" 7518de8d7fSPeter Avalos #include "hostfile.h" 7618de8d7fSPeter Avalos #include "auth.h" 7718de8d7fSPeter Avalos #include "session.h" 7818de8d7fSPeter Avalos #include "dispatch.h" 7918de8d7fSPeter Avalos #include "auth-options.h" 8018de8d7fSPeter Avalos #include "serverloop.h" 81*e9778795SPeter Avalos #include "ssherr.h" 8218de8d7fSPeter Avalos 8318de8d7fSPeter Avalos extern ServerOptions options; 8418de8d7fSPeter Avalos 8518de8d7fSPeter Avalos /* XXX */ 8618de8d7fSPeter Avalos extern Authctxt *the_authctxt; 8718de8d7fSPeter Avalos extern int use_privsep; 8818de8d7fSPeter Avalos 8918de8d7fSPeter Avalos static Buffer stdin_buffer; /* Buffer for stdin data. */ 9018de8d7fSPeter Avalos static Buffer stdout_buffer; /* Buffer for stdout data. */ 9118de8d7fSPeter Avalos static Buffer stderr_buffer; /* Buffer for stderr data. */ 9218de8d7fSPeter Avalos static int fdin; /* Descriptor for stdin (for writing) */ 9318de8d7fSPeter Avalos static int fdout; /* Descriptor for stdout (for reading); 9418de8d7fSPeter Avalos May be same number as fdin. */ 9518de8d7fSPeter Avalos static int fderr; /* Descriptor for stderr. May be -1. */ 9618de8d7fSPeter Avalos static long stdin_bytes = 0; /* Number of bytes written to stdin. */ 9718de8d7fSPeter Avalos static long stdout_bytes = 0; /* Number of stdout bytes sent to client. */ 9818de8d7fSPeter Avalos static long stderr_bytes = 0; /* Number of stderr bytes sent to client. */ 9918de8d7fSPeter Avalos static long fdout_bytes = 0; /* Number of stdout bytes read from program. */ 10018de8d7fSPeter Avalos static int stdin_eof = 0; /* EOF message received from client. */ 10118de8d7fSPeter Avalos static int fdout_eof = 0; /* EOF encountered reading from fdout. */ 10218de8d7fSPeter Avalos static int fderr_eof = 0; /* EOF encountered readung from fderr. */ 10318de8d7fSPeter Avalos static int fdin_is_tty = 0; /* fdin points to a tty. */ 10418de8d7fSPeter Avalos static int connection_in; /* Connection to client (input). */ 10518de8d7fSPeter Avalos static int connection_out; /* Connection to client (output). */ 10618de8d7fSPeter Avalos static int connection_closed = 0; /* Connection to client closed. */ 10718de8d7fSPeter Avalos static u_int buffer_high; /* "Soft" max buffer size. */ 10818de8d7fSPeter Avalos static int no_more_sessions = 0; /* Disallow further sessions. */ 10918de8d7fSPeter Avalos 11018de8d7fSPeter Avalos /* 11118de8d7fSPeter Avalos * This SIGCHLD kludge is used to detect when the child exits. The server 11218de8d7fSPeter Avalos * will exit after that, as soon as forwarded connections have terminated. 11318de8d7fSPeter Avalos */ 11418de8d7fSPeter Avalos 11518de8d7fSPeter Avalos static volatile sig_atomic_t child_terminated = 0; /* The child has terminated. */ 11618de8d7fSPeter Avalos 11718de8d7fSPeter Avalos /* Cleanup on signals (!use_privsep case only) */ 11818de8d7fSPeter Avalos static volatile sig_atomic_t received_sigterm = 0; 11918de8d7fSPeter Avalos 12018de8d7fSPeter Avalos /* prototypes */ 12118de8d7fSPeter Avalos static void server_init_dispatch(void); 12218de8d7fSPeter Avalos 12318de8d7fSPeter Avalos /* 12418de8d7fSPeter Avalos * we write to this pipe if a SIGCHLD is caught in order to avoid 12518de8d7fSPeter Avalos * the race between select() and child_terminated 12618de8d7fSPeter Avalos */ 12718de8d7fSPeter Avalos static int notify_pipe[2]; 12818de8d7fSPeter Avalos static void 12918de8d7fSPeter Avalos notify_setup(void) 13018de8d7fSPeter Avalos { 13118de8d7fSPeter Avalos if (pipe(notify_pipe) < 0) { 13218de8d7fSPeter Avalos error("pipe(notify_pipe) failed %s", strerror(errno)); 1331c188a7fSPeter Avalos } else if ((fcntl(notify_pipe[0], F_SETFD, FD_CLOEXEC) == -1) || 1341c188a7fSPeter Avalos (fcntl(notify_pipe[1], F_SETFD, FD_CLOEXEC) == -1)) { 13518de8d7fSPeter Avalos error("fcntl(notify_pipe, F_SETFD) failed %s", strerror(errno)); 13618de8d7fSPeter Avalos close(notify_pipe[0]); 13718de8d7fSPeter Avalos close(notify_pipe[1]); 13818de8d7fSPeter Avalos } else { 13918de8d7fSPeter Avalos set_nonblock(notify_pipe[0]); 14018de8d7fSPeter Avalos set_nonblock(notify_pipe[1]); 14118de8d7fSPeter Avalos return; 14218de8d7fSPeter Avalos } 14318de8d7fSPeter Avalos notify_pipe[0] = -1; /* read end */ 14418de8d7fSPeter Avalos notify_pipe[1] = -1; /* write end */ 14518de8d7fSPeter Avalos } 14618de8d7fSPeter Avalos static void 14718de8d7fSPeter Avalos notify_parent(void) 14818de8d7fSPeter Avalos { 14918de8d7fSPeter Avalos if (notify_pipe[1] != -1) 15036e94dc5SPeter Avalos (void)write(notify_pipe[1], "", 1); 15118de8d7fSPeter Avalos } 15218de8d7fSPeter Avalos static void 15318de8d7fSPeter Avalos notify_prepare(fd_set *readset) 15418de8d7fSPeter Avalos { 15518de8d7fSPeter Avalos if (notify_pipe[0] != -1) 15618de8d7fSPeter Avalos FD_SET(notify_pipe[0], readset); 15718de8d7fSPeter Avalos } 15818de8d7fSPeter Avalos static void 15918de8d7fSPeter Avalos notify_done(fd_set *readset) 16018de8d7fSPeter Avalos { 16118de8d7fSPeter Avalos char c; 16218de8d7fSPeter Avalos 16318de8d7fSPeter Avalos if (notify_pipe[0] != -1 && FD_ISSET(notify_pipe[0], readset)) 16418de8d7fSPeter Avalos while (read(notify_pipe[0], &c, 1) != -1) 16518de8d7fSPeter Avalos debug2("notify_done: reading"); 16618de8d7fSPeter Avalos } 16718de8d7fSPeter Avalos 16818de8d7fSPeter Avalos /*ARGSUSED*/ 16918de8d7fSPeter Avalos static void 17018de8d7fSPeter Avalos sigchld_handler(int sig) 17118de8d7fSPeter Avalos { 17218de8d7fSPeter Avalos int save_errno = errno; 17318de8d7fSPeter Avalos child_terminated = 1; 17418de8d7fSPeter Avalos #ifndef _UNICOS 17518de8d7fSPeter Avalos mysignal(SIGCHLD, sigchld_handler); 17618de8d7fSPeter Avalos #endif 17718de8d7fSPeter Avalos notify_parent(); 17818de8d7fSPeter Avalos errno = save_errno; 17918de8d7fSPeter Avalos } 18018de8d7fSPeter Avalos 18118de8d7fSPeter Avalos /*ARGSUSED*/ 18218de8d7fSPeter Avalos static void 18318de8d7fSPeter Avalos sigterm_handler(int sig) 18418de8d7fSPeter Avalos { 18518de8d7fSPeter Avalos received_sigterm = sig; 18618de8d7fSPeter Avalos } 18718de8d7fSPeter Avalos 18818de8d7fSPeter Avalos /* 18918de8d7fSPeter Avalos * Make packets from buffered stderr data, and buffer it for sending 19018de8d7fSPeter Avalos * to the client. 19118de8d7fSPeter Avalos */ 19218de8d7fSPeter Avalos static void 19318de8d7fSPeter Avalos make_packets_from_stderr_data(void) 19418de8d7fSPeter Avalos { 19518de8d7fSPeter Avalos u_int len; 19618de8d7fSPeter Avalos 19718de8d7fSPeter Avalos /* Send buffered stderr data to the client. */ 19818de8d7fSPeter Avalos while (buffer_len(&stderr_buffer) > 0 && 19918de8d7fSPeter Avalos packet_not_very_much_data_to_write()) { 20018de8d7fSPeter Avalos len = buffer_len(&stderr_buffer); 20118de8d7fSPeter Avalos if (packet_is_interactive()) { 20218de8d7fSPeter Avalos if (len > 512) 20318de8d7fSPeter Avalos len = 512; 20418de8d7fSPeter Avalos } else { 20518de8d7fSPeter Avalos /* Keep the packets at reasonable size. */ 20618de8d7fSPeter Avalos if (len > packet_get_maxsize()) 20718de8d7fSPeter Avalos len = packet_get_maxsize(); 20818de8d7fSPeter Avalos } 20918de8d7fSPeter Avalos packet_start(SSH_SMSG_STDERR_DATA); 21018de8d7fSPeter Avalos packet_put_string(buffer_ptr(&stderr_buffer), len); 21118de8d7fSPeter Avalos packet_send(); 21218de8d7fSPeter Avalos buffer_consume(&stderr_buffer, len); 21318de8d7fSPeter Avalos stderr_bytes += len; 21418de8d7fSPeter Avalos } 21518de8d7fSPeter Avalos } 21618de8d7fSPeter Avalos 21718de8d7fSPeter Avalos /* 21818de8d7fSPeter Avalos * Make packets from buffered stdout data, and buffer it for sending to the 21918de8d7fSPeter Avalos * client. 22018de8d7fSPeter Avalos */ 22118de8d7fSPeter Avalos static void 22218de8d7fSPeter Avalos make_packets_from_stdout_data(void) 22318de8d7fSPeter Avalos { 22418de8d7fSPeter Avalos u_int len; 22518de8d7fSPeter Avalos 22618de8d7fSPeter Avalos /* Send buffered stdout data to the client. */ 22718de8d7fSPeter Avalos while (buffer_len(&stdout_buffer) > 0 && 22818de8d7fSPeter Avalos packet_not_very_much_data_to_write()) { 22918de8d7fSPeter Avalos len = buffer_len(&stdout_buffer); 23018de8d7fSPeter Avalos if (packet_is_interactive()) { 23118de8d7fSPeter Avalos if (len > 512) 23218de8d7fSPeter Avalos len = 512; 23318de8d7fSPeter Avalos } else { 23418de8d7fSPeter Avalos /* Keep the packets at reasonable size. */ 23518de8d7fSPeter Avalos if (len > packet_get_maxsize()) 23618de8d7fSPeter Avalos len = packet_get_maxsize(); 23718de8d7fSPeter Avalos } 23818de8d7fSPeter Avalos packet_start(SSH_SMSG_STDOUT_DATA); 23918de8d7fSPeter Avalos packet_put_string(buffer_ptr(&stdout_buffer), len); 24018de8d7fSPeter Avalos packet_send(); 24118de8d7fSPeter Avalos buffer_consume(&stdout_buffer, len); 24218de8d7fSPeter Avalos stdout_bytes += len; 24318de8d7fSPeter Avalos } 24418de8d7fSPeter Avalos } 24518de8d7fSPeter Avalos 24618de8d7fSPeter Avalos static void 24718de8d7fSPeter Avalos client_alive_check(void) 24818de8d7fSPeter Avalos { 24918de8d7fSPeter Avalos int channel_id; 25018de8d7fSPeter Avalos 25118de8d7fSPeter Avalos /* timeout, check to see how many we have had */ 25240c002afSPeter Avalos if (packet_inc_alive_timeouts() > options.client_alive_count_max) { 25318de8d7fSPeter Avalos logit("Timeout, client not responding."); 25418de8d7fSPeter Avalos cleanup_exit(255); 25518de8d7fSPeter Avalos } 25618de8d7fSPeter Avalos 25718de8d7fSPeter Avalos /* 25818de8d7fSPeter Avalos * send a bogus global/channel request with "wantreply", 25918de8d7fSPeter Avalos * we should get back a failure 26018de8d7fSPeter Avalos */ 26118de8d7fSPeter Avalos if ((channel_id = channel_find_open()) == -1) { 26218de8d7fSPeter Avalos packet_start(SSH2_MSG_GLOBAL_REQUEST); 26318de8d7fSPeter Avalos packet_put_cstring("keepalive@openssh.com"); 26418de8d7fSPeter Avalos packet_put_char(1); /* boolean: want reply */ 26518de8d7fSPeter Avalos } else { 26618de8d7fSPeter Avalos channel_request_start(channel_id, "keepalive@openssh.com", 1); 26718de8d7fSPeter Avalos } 26818de8d7fSPeter Avalos packet_send(); 26918de8d7fSPeter Avalos } 27018de8d7fSPeter Avalos 27118de8d7fSPeter Avalos /* 27218de8d7fSPeter Avalos * Sleep in select() until we can do something. This will initialize the 27318de8d7fSPeter Avalos * select masks. Upon return, the masks will indicate which descriptors 27418de8d7fSPeter Avalos * have data or can accept data. Optionally, a maximum time can be specified 27518de8d7fSPeter Avalos * for the duration of the wait (0 = infinite). 27618de8d7fSPeter Avalos */ 27718de8d7fSPeter Avalos static void 27818de8d7fSPeter Avalos wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp, int *maxfdp, 279*e9778795SPeter Avalos u_int *nallocp, u_int64_t max_time_ms) 28018de8d7fSPeter Avalos { 28118de8d7fSPeter Avalos struct timeval tv, *tvp; 28218de8d7fSPeter Avalos int ret; 28399e85e0dSPeter Avalos time_t minwait_secs = 0; 28418de8d7fSPeter Avalos int client_alive_scheduled = 0; 28518de8d7fSPeter Avalos int program_alive_scheduled = 0; 28618de8d7fSPeter Avalos 28799e85e0dSPeter Avalos /* Allocate and update select() masks for channel descriptors. */ 28899e85e0dSPeter Avalos channel_prepare_select(readsetp, writesetp, maxfdp, nallocp, 28999e85e0dSPeter Avalos &minwait_secs, 0); 29099e85e0dSPeter Avalos 291*e9778795SPeter Avalos /* XXX need proper deadline system for rekey/client alive */ 29299e85e0dSPeter Avalos if (minwait_secs != 0) 293*e9778795SPeter Avalos max_time_ms = MIN(max_time_ms, (u_int)minwait_secs * 1000); 29499e85e0dSPeter Avalos 29518de8d7fSPeter Avalos /* 29618de8d7fSPeter Avalos * if using client_alive, set the max timeout accordingly, 29718de8d7fSPeter Avalos * and indicate that this particular timeout was for client 29818de8d7fSPeter Avalos * alive by setting the client_alive_scheduled flag. 29918de8d7fSPeter Avalos * 30018de8d7fSPeter Avalos * this could be randomized somewhat to make traffic 30118de8d7fSPeter Avalos * analysis more difficult, but we're not doing it yet. 30218de8d7fSPeter Avalos */ 303*e9778795SPeter Avalos if (compat20 && options.client_alive_interval) { 304*e9778795SPeter Avalos uint64_t keepalive_ms = 305*e9778795SPeter Avalos (uint64_t)options.client_alive_interval * 1000; 306*e9778795SPeter Avalos 30718de8d7fSPeter Avalos client_alive_scheduled = 1; 308*e9778795SPeter Avalos if (max_time_ms == 0 || max_time_ms > keepalive_ms) 309*e9778795SPeter Avalos max_time_ms = keepalive_ms; 31018de8d7fSPeter Avalos } 31118de8d7fSPeter Avalos 31218de8d7fSPeter Avalos if (compat20) { 31318de8d7fSPeter Avalos #if 0 31418de8d7fSPeter Avalos /* wrong: bad condition XXX */ 31518de8d7fSPeter Avalos if (channel_not_very_much_buffered_data()) 31618de8d7fSPeter Avalos #endif 31718de8d7fSPeter Avalos FD_SET(connection_in, *readsetp); 31818de8d7fSPeter Avalos } else { 31918de8d7fSPeter Avalos /* 32018de8d7fSPeter Avalos * Read packets from the client unless we have too much 32118de8d7fSPeter Avalos * buffered stdin or channel data. 32218de8d7fSPeter Avalos */ 32318de8d7fSPeter Avalos if (buffer_len(&stdin_buffer) < buffer_high && 32418de8d7fSPeter Avalos channel_not_very_much_buffered_data()) 32518de8d7fSPeter Avalos FD_SET(connection_in, *readsetp); 32618de8d7fSPeter Avalos /* 32718de8d7fSPeter Avalos * If there is not too much data already buffered going to 32818de8d7fSPeter Avalos * the client, try to get some more data from the program. 32918de8d7fSPeter Avalos */ 33018de8d7fSPeter Avalos if (packet_not_very_much_data_to_write()) { 33118de8d7fSPeter Avalos program_alive_scheduled = child_terminated; 33218de8d7fSPeter Avalos if (!fdout_eof) 33318de8d7fSPeter Avalos FD_SET(fdout, *readsetp); 33418de8d7fSPeter Avalos if (!fderr_eof) 33518de8d7fSPeter Avalos FD_SET(fderr, *readsetp); 33618de8d7fSPeter Avalos } 33718de8d7fSPeter Avalos /* 33818de8d7fSPeter Avalos * If we have buffered data, try to write some of that data 33918de8d7fSPeter Avalos * to the program. 34018de8d7fSPeter Avalos */ 34118de8d7fSPeter Avalos if (fdin != -1 && buffer_len(&stdin_buffer) > 0) 34218de8d7fSPeter Avalos FD_SET(fdin, *writesetp); 34318de8d7fSPeter Avalos } 34418de8d7fSPeter Avalos notify_prepare(*readsetp); 34518de8d7fSPeter Avalos 34618de8d7fSPeter Avalos /* 34718de8d7fSPeter Avalos * If we have buffered packet data going to the client, mark that 34818de8d7fSPeter Avalos * descriptor. 34918de8d7fSPeter Avalos */ 35018de8d7fSPeter Avalos if (packet_have_data_to_write()) 35118de8d7fSPeter Avalos FD_SET(connection_out, *writesetp); 35218de8d7fSPeter Avalos 35318de8d7fSPeter Avalos /* 35418de8d7fSPeter Avalos * If child has terminated and there is enough buffer space to read 35518de8d7fSPeter Avalos * from it, then read as much as is available and exit. 35618de8d7fSPeter Avalos */ 35718de8d7fSPeter Avalos if (child_terminated && packet_not_very_much_data_to_write()) 358*e9778795SPeter Avalos if (max_time_ms == 0 || client_alive_scheduled) 359*e9778795SPeter Avalos max_time_ms = 100; 36018de8d7fSPeter Avalos 361*e9778795SPeter Avalos if (max_time_ms == 0) 36218de8d7fSPeter Avalos tvp = NULL; 36318de8d7fSPeter Avalos else { 364*e9778795SPeter Avalos tv.tv_sec = max_time_ms / 1000; 365*e9778795SPeter Avalos tv.tv_usec = 1000 * (max_time_ms % 1000); 36618de8d7fSPeter Avalos tvp = &tv; 36718de8d7fSPeter Avalos } 36818de8d7fSPeter Avalos 36918de8d7fSPeter Avalos /* Wait for something to happen, or the timeout to expire. */ 37018de8d7fSPeter Avalos ret = select((*maxfdp)+1, *readsetp, *writesetp, NULL, tvp); 37118de8d7fSPeter Avalos 37218de8d7fSPeter Avalos if (ret == -1) { 37318de8d7fSPeter Avalos memset(*readsetp, 0, *nallocp); 37418de8d7fSPeter Avalos memset(*writesetp, 0, *nallocp); 37518de8d7fSPeter Avalos if (errno != EINTR) 37618de8d7fSPeter Avalos error("select: %.100s", strerror(errno)); 37718de8d7fSPeter Avalos } else { 37818de8d7fSPeter Avalos if (ret == 0 && client_alive_scheduled) 37918de8d7fSPeter Avalos client_alive_check(); 38018de8d7fSPeter Avalos if (!compat20 && program_alive_scheduled && fdin_is_tty) { 38118de8d7fSPeter Avalos if (!fdout_eof) 38218de8d7fSPeter Avalos FD_SET(fdout, *readsetp); 38318de8d7fSPeter Avalos if (!fderr_eof) 38418de8d7fSPeter Avalos FD_SET(fderr, *readsetp); 38518de8d7fSPeter Avalos } 38618de8d7fSPeter Avalos } 38718de8d7fSPeter Avalos 38818de8d7fSPeter Avalos notify_done(*readsetp); 38918de8d7fSPeter Avalos } 39018de8d7fSPeter Avalos 39118de8d7fSPeter Avalos /* 39218de8d7fSPeter Avalos * Processes input from the client and the program. Input data is stored 39318de8d7fSPeter Avalos * in buffers and processed later. 39418de8d7fSPeter Avalos */ 39518de8d7fSPeter Avalos static void 39618de8d7fSPeter Avalos process_input(fd_set *readset) 39718de8d7fSPeter Avalos { 398*e9778795SPeter Avalos struct ssh *ssh = active_state; /* XXX */ 39918de8d7fSPeter Avalos int len; 40018de8d7fSPeter Avalos char buf[16384]; 40118de8d7fSPeter Avalos 40218de8d7fSPeter Avalos /* Read and buffer any input data from the client. */ 40318de8d7fSPeter Avalos if (FD_ISSET(connection_in, readset)) { 404*e9778795SPeter Avalos len = read(connection_in, buf, sizeof(buf)); 40518de8d7fSPeter Avalos if (len == 0) { 406*e9778795SPeter Avalos verbose("Connection closed by %.100s port %d", 407*e9778795SPeter Avalos ssh_remote_ipaddr(ssh), ssh_remote_port(ssh)); 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 " 416*e9778795SPeter Avalos "%.100s port %d: %.100s", 417*e9778795SPeter Avalos ssh_remote_ipaddr(ssh), 418*e9778795SPeter Avalos ssh_remote_port(ssh), strerror(errno)); 41918de8d7fSPeter Avalos cleanup_exit(255); 42018de8d7fSPeter Avalos } 42118de8d7fSPeter Avalos } else { 42218de8d7fSPeter Avalos /* Buffer any received data. */ 42318de8d7fSPeter Avalos packet_process_incoming(buf, len); 42418de8d7fSPeter Avalos } 42518de8d7fSPeter Avalos } 42618de8d7fSPeter Avalos if (compat20) 42718de8d7fSPeter Avalos return; 42818de8d7fSPeter Avalos 42918de8d7fSPeter Avalos /* Read and buffer any available stdout data from the program. */ 43018de8d7fSPeter Avalos if (!fdout_eof && FD_ISSET(fdout, readset)) { 43118de8d7fSPeter Avalos errno = 0; 43218de8d7fSPeter Avalos len = read(fdout, buf, sizeof(buf)); 43318de8d7fSPeter Avalos if (len < 0 && (errno == EINTR || ((errno == EAGAIN || 43418de8d7fSPeter Avalos errno == EWOULDBLOCK) && !child_terminated))) { 43518de8d7fSPeter Avalos /* do nothing */ 43618de8d7fSPeter Avalos #ifndef PTY_ZEROREAD 43718de8d7fSPeter Avalos } else if (len <= 0) { 43818de8d7fSPeter Avalos #else 43918de8d7fSPeter Avalos } else if ((!isatty(fdout) && len <= 0) || 44018de8d7fSPeter Avalos (isatty(fdout) && (len < 0 || (len == 0 && errno != 0)))) { 44118de8d7fSPeter Avalos #endif 44218de8d7fSPeter Avalos fdout_eof = 1; 44318de8d7fSPeter Avalos } else { 44418de8d7fSPeter Avalos buffer_append(&stdout_buffer, buf, len); 44518de8d7fSPeter Avalos fdout_bytes += len; 44618de8d7fSPeter Avalos } 44718de8d7fSPeter Avalos } 44818de8d7fSPeter Avalos /* Read and buffer any available stderr data from the program. */ 44918de8d7fSPeter Avalos if (!fderr_eof && FD_ISSET(fderr, readset)) { 45018de8d7fSPeter Avalos errno = 0; 45118de8d7fSPeter Avalos len = read(fderr, buf, sizeof(buf)); 45218de8d7fSPeter Avalos if (len < 0 && (errno == EINTR || ((errno == EAGAIN || 45318de8d7fSPeter Avalos errno == EWOULDBLOCK) && !child_terminated))) { 45418de8d7fSPeter Avalos /* do nothing */ 45518de8d7fSPeter Avalos #ifndef PTY_ZEROREAD 45618de8d7fSPeter Avalos } else if (len <= 0) { 45718de8d7fSPeter Avalos #else 45818de8d7fSPeter Avalos } else if ((!isatty(fderr) && len <= 0) || 45918de8d7fSPeter Avalos (isatty(fderr) && (len < 0 || (len == 0 && errno != 0)))) { 46018de8d7fSPeter Avalos #endif 46118de8d7fSPeter Avalos fderr_eof = 1; 46218de8d7fSPeter Avalos } else { 46318de8d7fSPeter Avalos buffer_append(&stderr_buffer, buf, len); 46418de8d7fSPeter Avalos } 46518de8d7fSPeter Avalos } 46618de8d7fSPeter Avalos } 46718de8d7fSPeter Avalos 46818de8d7fSPeter Avalos /* 46918de8d7fSPeter Avalos * Sends data from internal buffers to client program stdin. 47018de8d7fSPeter Avalos */ 47118de8d7fSPeter Avalos static void 47218de8d7fSPeter Avalos process_output(fd_set *writeset) 47318de8d7fSPeter Avalos { 47418de8d7fSPeter Avalos struct termios tio; 47518de8d7fSPeter Avalos u_char *data; 47618de8d7fSPeter Avalos u_int dlen; 47718de8d7fSPeter Avalos int len; 47818de8d7fSPeter Avalos 47918de8d7fSPeter Avalos /* Write buffered data to program stdin. */ 48018de8d7fSPeter Avalos if (!compat20 && fdin != -1 && FD_ISSET(fdin, writeset)) { 48118de8d7fSPeter Avalos data = buffer_ptr(&stdin_buffer); 48218de8d7fSPeter Avalos dlen = buffer_len(&stdin_buffer); 48318de8d7fSPeter Avalos len = write(fdin, data, dlen); 48418de8d7fSPeter Avalos if (len < 0 && 48518de8d7fSPeter Avalos (errno == EINTR || errno == EAGAIN || errno == EWOULDBLOCK)) { 48618de8d7fSPeter Avalos /* do nothing */ 48718de8d7fSPeter Avalos } else if (len <= 0) { 48818de8d7fSPeter Avalos if (fdin != fdout) 48918de8d7fSPeter Avalos close(fdin); 49018de8d7fSPeter Avalos else 49118de8d7fSPeter Avalos shutdown(fdin, SHUT_WR); /* We will no longer send. */ 49218de8d7fSPeter Avalos fdin = -1; 49318de8d7fSPeter Avalos } else { 49418de8d7fSPeter Avalos /* Successful write. */ 49518de8d7fSPeter Avalos if (fdin_is_tty && dlen >= 1 && data[0] != '\r' && 49618de8d7fSPeter Avalos tcgetattr(fdin, &tio) == 0 && 49718de8d7fSPeter Avalos !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) { 49818de8d7fSPeter Avalos /* 49918de8d7fSPeter Avalos * Simulate echo to reduce the impact of 50018de8d7fSPeter Avalos * traffic analysis 50118de8d7fSPeter Avalos */ 50218de8d7fSPeter Avalos packet_send_ignore(len); 50318de8d7fSPeter Avalos packet_send(); 50418de8d7fSPeter Avalos } 50518de8d7fSPeter Avalos /* Consume the data from the buffer. */ 50618de8d7fSPeter Avalos buffer_consume(&stdin_buffer, len); 50718de8d7fSPeter Avalos /* Update the count of bytes written to the program. */ 50818de8d7fSPeter Avalos stdin_bytes += len; 50918de8d7fSPeter Avalos } 51018de8d7fSPeter Avalos } 51118de8d7fSPeter Avalos /* Send any buffered packet data to the client. */ 51218de8d7fSPeter Avalos if (FD_ISSET(connection_out, writeset)) 51318de8d7fSPeter Avalos packet_write_poll(); 51418de8d7fSPeter Avalos } 51518de8d7fSPeter Avalos 51618de8d7fSPeter Avalos /* 51718de8d7fSPeter Avalos * Wait until all buffered output has been sent to the client. 51818de8d7fSPeter Avalos * This is used when the program terminates. 51918de8d7fSPeter Avalos */ 52018de8d7fSPeter Avalos static void 52118de8d7fSPeter Avalos drain_output(void) 52218de8d7fSPeter Avalos { 52318de8d7fSPeter Avalos /* Send any buffered stdout data to the client. */ 52418de8d7fSPeter Avalos if (buffer_len(&stdout_buffer) > 0) { 52518de8d7fSPeter Avalos packet_start(SSH_SMSG_STDOUT_DATA); 52618de8d7fSPeter Avalos packet_put_string(buffer_ptr(&stdout_buffer), 52718de8d7fSPeter Avalos buffer_len(&stdout_buffer)); 52818de8d7fSPeter Avalos packet_send(); 52918de8d7fSPeter Avalos /* Update the count of sent bytes. */ 53018de8d7fSPeter Avalos stdout_bytes += buffer_len(&stdout_buffer); 53118de8d7fSPeter Avalos } 53218de8d7fSPeter Avalos /* Send any buffered stderr data to the client. */ 53318de8d7fSPeter Avalos if (buffer_len(&stderr_buffer) > 0) { 53418de8d7fSPeter Avalos packet_start(SSH_SMSG_STDERR_DATA); 53518de8d7fSPeter Avalos packet_put_string(buffer_ptr(&stderr_buffer), 53618de8d7fSPeter Avalos buffer_len(&stderr_buffer)); 53718de8d7fSPeter Avalos packet_send(); 53818de8d7fSPeter Avalos /* Update the count of sent bytes. */ 53918de8d7fSPeter Avalos stderr_bytes += buffer_len(&stderr_buffer); 54018de8d7fSPeter Avalos } 54118de8d7fSPeter Avalos /* Wait until all buffered data has been written to the client. */ 54218de8d7fSPeter Avalos packet_write_wait(); 54318de8d7fSPeter Avalos } 54418de8d7fSPeter Avalos 54518de8d7fSPeter Avalos static void 54618de8d7fSPeter Avalos process_buffered_input_packets(void) 54718de8d7fSPeter Avalos { 548*e9778795SPeter Avalos dispatch_run(DISPATCH_NONBLOCK, NULL, active_state); 54918de8d7fSPeter Avalos } 55018de8d7fSPeter Avalos 55118de8d7fSPeter Avalos /* 55218de8d7fSPeter Avalos * Performs the interactive session. This handles data transmission between 55318de8d7fSPeter Avalos * the client and the program. Note that the notion of stdin, stdout, and 55418de8d7fSPeter Avalos * stderr in this function is sort of reversed: this function writes to 55518de8d7fSPeter Avalos * stdin (of the child program), and reads from stdout and stderr (of the 55618de8d7fSPeter Avalos * child program). 55718de8d7fSPeter Avalos */ 55818de8d7fSPeter Avalos void 55918de8d7fSPeter Avalos server_loop(pid_t pid, int fdin_arg, int fdout_arg, int fderr_arg) 56018de8d7fSPeter Avalos { 56118de8d7fSPeter Avalos fd_set *readset = NULL, *writeset = NULL; 56218de8d7fSPeter Avalos int max_fd = 0; 56318de8d7fSPeter Avalos u_int nalloc = 0; 56418de8d7fSPeter Avalos int wait_status; /* Status returned by wait(). */ 56518de8d7fSPeter Avalos pid_t wait_pid; /* pid returned by wait(). */ 56618de8d7fSPeter Avalos int waiting_termination = 0; /* Have displayed waiting close message. */ 56736e94dc5SPeter Avalos u_int64_t max_time_milliseconds; 56818de8d7fSPeter Avalos u_int previous_stdout_buffer_bytes; 56918de8d7fSPeter Avalos u_int stdout_buffer_bytes; 57018de8d7fSPeter Avalos int type; 57118de8d7fSPeter Avalos 57218de8d7fSPeter Avalos debug("Entering interactive session."); 57318de8d7fSPeter Avalos 57418de8d7fSPeter Avalos /* Initialize the SIGCHLD kludge. */ 57518de8d7fSPeter Avalos child_terminated = 0; 57618de8d7fSPeter Avalos mysignal(SIGCHLD, sigchld_handler); 57718de8d7fSPeter Avalos 57818de8d7fSPeter Avalos if (!use_privsep) { 57918de8d7fSPeter Avalos signal(SIGTERM, sigterm_handler); 58018de8d7fSPeter Avalos signal(SIGINT, sigterm_handler); 58118de8d7fSPeter Avalos signal(SIGQUIT, sigterm_handler); 58218de8d7fSPeter Avalos } 58318de8d7fSPeter Avalos 58418de8d7fSPeter Avalos /* Initialize our global variables. */ 58518de8d7fSPeter Avalos fdin = fdin_arg; 58618de8d7fSPeter Avalos fdout = fdout_arg; 58718de8d7fSPeter Avalos fderr = fderr_arg; 58818de8d7fSPeter Avalos 58918de8d7fSPeter Avalos /* nonblocking IO */ 59018de8d7fSPeter Avalos set_nonblock(fdin); 59118de8d7fSPeter Avalos set_nonblock(fdout); 59218de8d7fSPeter Avalos /* we don't have stderr for interactive terminal sessions, see below */ 59318de8d7fSPeter Avalos if (fderr != -1) 59418de8d7fSPeter Avalos set_nonblock(fderr); 59518de8d7fSPeter Avalos 59618de8d7fSPeter Avalos if (!(datafellows & SSH_BUG_IGNOREMSG) && isatty(fdin)) 59718de8d7fSPeter Avalos fdin_is_tty = 1; 59818de8d7fSPeter Avalos 59918de8d7fSPeter Avalos connection_in = packet_get_connection_in(); 60018de8d7fSPeter Avalos connection_out = packet_get_connection_out(); 60118de8d7fSPeter Avalos 60218de8d7fSPeter Avalos notify_setup(); 60318de8d7fSPeter Avalos 60418de8d7fSPeter Avalos previous_stdout_buffer_bytes = 0; 60518de8d7fSPeter Avalos 60618de8d7fSPeter Avalos /* Set approximate I/O buffer size. */ 60718de8d7fSPeter Avalos if (packet_is_interactive()) 60818de8d7fSPeter Avalos buffer_high = 4096; 60918de8d7fSPeter Avalos else 61018de8d7fSPeter Avalos buffer_high = 64 * 1024; 61118de8d7fSPeter Avalos 61218de8d7fSPeter Avalos #if 0 61318de8d7fSPeter Avalos /* Initialize max_fd to the maximum of the known file descriptors. */ 61418de8d7fSPeter Avalos max_fd = MAX(connection_in, connection_out); 61518de8d7fSPeter Avalos max_fd = MAX(max_fd, fdin); 61618de8d7fSPeter Avalos max_fd = MAX(max_fd, fdout); 61718de8d7fSPeter Avalos if (fderr != -1) 61818de8d7fSPeter Avalos max_fd = MAX(max_fd, fderr); 61918de8d7fSPeter Avalos #endif 62018de8d7fSPeter Avalos 62118de8d7fSPeter Avalos /* Initialize Initialize buffers. */ 62218de8d7fSPeter Avalos buffer_init(&stdin_buffer); 62318de8d7fSPeter Avalos buffer_init(&stdout_buffer); 62418de8d7fSPeter Avalos buffer_init(&stderr_buffer); 62518de8d7fSPeter Avalos 62618de8d7fSPeter Avalos /* 62718de8d7fSPeter Avalos * If we have no separate fderr (which is the case when we have a pty 62818de8d7fSPeter Avalos * - there we cannot make difference between data sent to stdout and 62918de8d7fSPeter Avalos * stderr), indicate that we have seen an EOF from stderr. This way 63018de8d7fSPeter Avalos * we don't need to check the descriptor everywhere. 63118de8d7fSPeter Avalos */ 63218de8d7fSPeter Avalos if (fderr == -1) 63318de8d7fSPeter Avalos fderr_eof = 1; 63418de8d7fSPeter Avalos 63518de8d7fSPeter Avalos server_init_dispatch(); 63618de8d7fSPeter Avalos 63718de8d7fSPeter Avalos /* Main loop of the server for the interactive session mode. */ 63818de8d7fSPeter Avalos for (;;) { 63918de8d7fSPeter Avalos 64018de8d7fSPeter Avalos /* Process buffered packets from the client. */ 64118de8d7fSPeter Avalos process_buffered_input_packets(); 64218de8d7fSPeter Avalos 64318de8d7fSPeter Avalos /* 64418de8d7fSPeter Avalos * If we have received eof, and there is no more pending 64518de8d7fSPeter Avalos * input data, cause a real eof by closing fdin. 64618de8d7fSPeter Avalos */ 64718de8d7fSPeter Avalos if (stdin_eof && fdin != -1 && buffer_len(&stdin_buffer) == 0) { 64818de8d7fSPeter Avalos if (fdin != fdout) 64918de8d7fSPeter Avalos close(fdin); 65018de8d7fSPeter Avalos else 65118de8d7fSPeter Avalos shutdown(fdin, SHUT_WR); /* We will no longer send. */ 65218de8d7fSPeter Avalos fdin = -1; 65318de8d7fSPeter Avalos } 65418de8d7fSPeter Avalos /* Make packets from buffered stderr data to send to the client. */ 65518de8d7fSPeter Avalos make_packets_from_stderr_data(); 65618de8d7fSPeter Avalos 65718de8d7fSPeter Avalos /* 65818de8d7fSPeter Avalos * Make packets from buffered stdout data to send to the 65918de8d7fSPeter Avalos * client. If there is very little to send, this arranges to 66018de8d7fSPeter Avalos * not send them now, but to wait a short while to see if we 66118de8d7fSPeter Avalos * are getting more data. This is necessary, as some systems 66218de8d7fSPeter Avalos * wake up readers from a pty after each separate character. 66318de8d7fSPeter Avalos */ 66418de8d7fSPeter Avalos max_time_milliseconds = 0; 66518de8d7fSPeter Avalos stdout_buffer_bytes = buffer_len(&stdout_buffer); 66618de8d7fSPeter Avalos if (stdout_buffer_bytes != 0 && stdout_buffer_bytes < 256 && 66718de8d7fSPeter Avalos stdout_buffer_bytes != previous_stdout_buffer_bytes) { 66818de8d7fSPeter Avalos /* try again after a while */ 66918de8d7fSPeter Avalos max_time_milliseconds = 10; 67018de8d7fSPeter Avalos } else { 67118de8d7fSPeter Avalos /* Send it now. */ 67218de8d7fSPeter Avalos make_packets_from_stdout_data(); 67318de8d7fSPeter Avalos } 67418de8d7fSPeter Avalos previous_stdout_buffer_bytes = buffer_len(&stdout_buffer); 67518de8d7fSPeter Avalos 67618de8d7fSPeter Avalos /* Send channel data to the client. */ 67718de8d7fSPeter Avalos if (packet_not_very_much_data_to_write()) 67818de8d7fSPeter Avalos channel_output_poll(); 67918de8d7fSPeter Avalos 68018de8d7fSPeter Avalos /* 68118de8d7fSPeter Avalos * Bail out of the loop if the program has closed its output 68218de8d7fSPeter Avalos * descriptors, and we have no more data to send to the 68318de8d7fSPeter Avalos * client, and there is no pending buffered data. 68418de8d7fSPeter Avalos */ 68518de8d7fSPeter Avalos if (fdout_eof && fderr_eof && !packet_have_data_to_write() && 68618de8d7fSPeter Avalos buffer_len(&stdout_buffer) == 0 && buffer_len(&stderr_buffer) == 0) { 68718de8d7fSPeter Avalos if (!channel_still_open()) 68818de8d7fSPeter Avalos break; 68918de8d7fSPeter Avalos if (!waiting_termination) { 69018de8d7fSPeter Avalos const char *s = "Waiting for forwarded connections to terminate...\r\n"; 69118de8d7fSPeter Avalos char *cp; 69218de8d7fSPeter Avalos waiting_termination = 1; 69318de8d7fSPeter Avalos buffer_append(&stderr_buffer, s, strlen(s)); 69418de8d7fSPeter Avalos 69518de8d7fSPeter Avalos /* Display list of open channels. */ 69618de8d7fSPeter Avalos cp = channel_open_message(); 69718de8d7fSPeter Avalos buffer_append(&stderr_buffer, cp, strlen(cp)); 69836e94dc5SPeter Avalos free(cp); 69918de8d7fSPeter Avalos } 70018de8d7fSPeter Avalos } 70118de8d7fSPeter Avalos max_fd = MAX(connection_in, connection_out); 70218de8d7fSPeter Avalos max_fd = MAX(max_fd, fdin); 70318de8d7fSPeter Avalos max_fd = MAX(max_fd, fdout); 70418de8d7fSPeter Avalos max_fd = MAX(max_fd, fderr); 70518de8d7fSPeter Avalos max_fd = MAX(max_fd, notify_pipe[0]); 70618de8d7fSPeter Avalos 70718de8d7fSPeter Avalos /* Sleep in select() until we can do something. */ 70818de8d7fSPeter Avalos wait_until_can_do_something(&readset, &writeset, &max_fd, 70918de8d7fSPeter Avalos &nalloc, max_time_milliseconds); 71018de8d7fSPeter Avalos 71118de8d7fSPeter Avalos if (received_sigterm) { 71236e94dc5SPeter Avalos logit("Exiting on signal %d", (int)received_sigterm); 71318de8d7fSPeter Avalos /* Clean up sessions, utmp, etc. */ 71418de8d7fSPeter Avalos cleanup_exit(255); 71518de8d7fSPeter Avalos } 71618de8d7fSPeter Avalos 71718de8d7fSPeter Avalos /* Process any channel events. */ 71818de8d7fSPeter Avalos channel_after_select(readset, writeset); 71918de8d7fSPeter Avalos 72018de8d7fSPeter Avalos /* Process input from the client and from program stdout/stderr. */ 72118de8d7fSPeter Avalos process_input(readset); 72218de8d7fSPeter Avalos 72318de8d7fSPeter Avalos /* Process output to the client and to program stdin. */ 72418de8d7fSPeter Avalos process_output(writeset); 72518de8d7fSPeter Avalos } 72636e94dc5SPeter Avalos free(readset); 72736e94dc5SPeter Avalos free(writeset); 72818de8d7fSPeter Avalos 72918de8d7fSPeter Avalos /* Cleanup and termination code. */ 73018de8d7fSPeter Avalos 73118de8d7fSPeter Avalos /* Wait until all output has been sent to the client. */ 73218de8d7fSPeter Avalos drain_output(); 73318de8d7fSPeter Avalos 73418de8d7fSPeter Avalos debug("End of interactive session; stdin %ld, stdout (read %ld, sent %ld), stderr %ld bytes.", 73518de8d7fSPeter Avalos stdin_bytes, fdout_bytes, stdout_bytes, stderr_bytes); 73618de8d7fSPeter Avalos 73718de8d7fSPeter Avalos /* Free and clear the buffers. */ 73818de8d7fSPeter Avalos buffer_free(&stdin_buffer); 73918de8d7fSPeter Avalos buffer_free(&stdout_buffer); 74018de8d7fSPeter Avalos buffer_free(&stderr_buffer); 74118de8d7fSPeter Avalos 74218de8d7fSPeter Avalos /* Close the file descriptors. */ 74318de8d7fSPeter Avalos if (fdout != -1) 74418de8d7fSPeter Avalos close(fdout); 74518de8d7fSPeter Avalos fdout = -1; 74618de8d7fSPeter Avalos fdout_eof = 1; 74718de8d7fSPeter Avalos if (fderr != -1) 74818de8d7fSPeter Avalos close(fderr); 74918de8d7fSPeter Avalos fderr = -1; 75018de8d7fSPeter Avalos fderr_eof = 1; 75118de8d7fSPeter Avalos if (fdin != -1) 75218de8d7fSPeter Avalos close(fdin); 75318de8d7fSPeter Avalos fdin = -1; 75418de8d7fSPeter Avalos 75518de8d7fSPeter Avalos channel_free_all(); 75618de8d7fSPeter Avalos 75718de8d7fSPeter Avalos /* We no longer want our SIGCHLD handler to be called. */ 75818de8d7fSPeter Avalos mysignal(SIGCHLD, SIG_DFL); 75918de8d7fSPeter Avalos 76018de8d7fSPeter Avalos while ((wait_pid = waitpid(-1, &wait_status, 0)) < 0) 76118de8d7fSPeter Avalos if (errno != EINTR) 76218de8d7fSPeter Avalos packet_disconnect("wait: %.100s", strerror(errno)); 76318de8d7fSPeter Avalos if (wait_pid != pid) 76418de8d7fSPeter Avalos error("Strange, wait returned pid %ld, expected %ld", 76518de8d7fSPeter Avalos (long)wait_pid, (long)pid); 76618de8d7fSPeter Avalos 76718de8d7fSPeter Avalos /* Check if it exited normally. */ 76818de8d7fSPeter Avalos if (WIFEXITED(wait_status)) { 76918de8d7fSPeter Avalos /* Yes, normal exit. Get exit status and send it to the client. */ 77018de8d7fSPeter Avalos debug("Command exited with status %d.", WEXITSTATUS(wait_status)); 77118de8d7fSPeter Avalos packet_start(SSH_SMSG_EXITSTATUS); 77218de8d7fSPeter Avalos packet_put_int(WEXITSTATUS(wait_status)); 77318de8d7fSPeter Avalos packet_send(); 77418de8d7fSPeter Avalos packet_write_wait(); 77518de8d7fSPeter Avalos 77618de8d7fSPeter Avalos /* 77718de8d7fSPeter Avalos * Wait for exit confirmation. Note that there might be 77818de8d7fSPeter Avalos * other packets coming before it; however, the program has 77918de8d7fSPeter Avalos * already died so we just ignore them. The client is 78018de8d7fSPeter Avalos * supposed to respond with the confirmation when it receives 78118de8d7fSPeter Avalos * the exit status. 78218de8d7fSPeter Avalos */ 78318de8d7fSPeter Avalos do { 78418de8d7fSPeter Avalos type = packet_read(); 78518de8d7fSPeter Avalos } 78618de8d7fSPeter Avalos while (type != SSH_CMSG_EXIT_CONFIRMATION); 78718de8d7fSPeter Avalos 78818de8d7fSPeter Avalos debug("Received exit confirmation."); 78918de8d7fSPeter Avalos return; 79018de8d7fSPeter Avalos } 79118de8d7fSPeter Avalos /* Check if the program terminated due to a signal. */ 79218de8d7fSPeter Avalos if (WIFSIGNALED(wait_status)) 79318de8d7fSPeter Avalos packet_disconnect("Command terminated on signal %d.", 79418de8d7fSPeter Avalos WTERMSIG(wait_status)); 79518de8d7fSPeter Avalos 79618de8d7fSPeter Avalos /* Some weird exit cause. Just exit. */ 79718de8d7fSPeter Avalos packet_disconnect("wait returned status %04x.", wait_status); 79818de8d7fSPeter Avalos /* NOTREACHED */ 79918de8d7fSPeter Avalos } 80018de8d7fSPeter Avalos 80118de8d7fSPeter Avalos static void 80218de8d7fSPeter Avalos collect_children(void) 80318de8d7fSPeter Avalos { 80418de8d7fSPeter Avalos pid_t pid; 80518de8d7fSPeter Avalos sigset_t oset, nset; 80618de8d7fSPeter Avalos int status; 80718de8d7fSPeter Avalos 80818de8d7fSPeter Avalos /* block SIGCHLD while we check for dead children */ 80918de8d7fSPeter Avalos sigemptyset(&nset); 81018de8d7fSPeter Avalos sigaddset(&nset, SIGCHLD); 81118de8d7fSPeter Avalos sigprocmask(SIG_BLOCK, &nset, &oset); 81218de8d7fSPeter Avalos if (child_terminated) { 81318de8d7fSPeter Avalos debug("Received SIGCHLD."); 81418de8d7fSPeter Avalos while ((pid = waitpid(-1, &status, WNOHANG)) > 0 || 81518de8d7fSPeter Avalos (pid < 0 && errno == EINTR)) 81618de8d7fSPeter Avalos if (pid > 0) 81718de8d7fSPeter Avalos session_close_by_pid(pid, status); 81818de8d7fSPeter Avalos child_terminated = 0; 81918de8d7fSPeter Avalos } 82018de8d7fSPeter Avalos sigprocmask(SIG_SETMASK, &oset, NULL); 82118de8d7fSPeter Avalos } 82218de8d7fSPeter Avalos 82318de8d7fSPeter Avalos void 82418de8d7fSPeter Avalos server_loop2(Authctxt *authctxt) 82518de8d7fSPeter Avalos { 82618de8d7fSPeter Avalos fd_set *readset = NULL, *writeset = NULL; 827*e9778795SPeter Avalos int max_fd; 82836e94dc5SPeter Avalos u_int nalloc = 0; 82936e94dc5SPeter Avalos u_int64_t rekey_timeout_ms = 0; 83018de8d7fSPeter Avalos 83118de8d7fSPeter Avalos debug("Entering interactive session for SSH2."); 83218de8d7fSPeter Avalos 83318de8d7fSPeter Avalos mysignal(SIGCHLD, sigchld_handler); 83418de8d7fSPeter Avalos child_terminated = 0; 83518de8d7fSPeter Avalos connection_in = packet_get_connection_in(); 83618de8d7fSPeter Avalos connection_out = packet_get_connection_out(); 83718de8d7fSPeter Avalos 83818de8d7fSPeter Avalos if (!use_privsep) { 83918de8d7fSPeter Avalos signal(SIGTERM, sigterm_handler); 84018de8d7fSPeter Avalos signal(SIGINT, sigterm_handler); 84118de8d7fSPeter Avalos signal(SIGQUIT, sigterm_handler); 84218de8d7fSPeter Avalos } 84318de8d7fSPeter Avalos 84418de8d7fSPeter Avalos notify_setup(); 84518de8d7fSPeter Avalos 84618de8d7fSPeter Avalos max_fd = MAX(connection_in, connection_out); 84718de8d7fSPeter Avalos max_fd = MAX(max_fd, notify_pipe[0]); 84818de8d7fSPeter Avalos 84918de8d7fSPeter Avalos server_init_dispatch(); 85018de8d7fSPeter Avalos 85118de8d7fSPeter Avalos for (;;) { 85218de8d7fSPeter Avalos process_buffered_input_packets(); 85318de8d7fSPeter Avalos 854*e9778795SPeter Avalos if (!ssh_packet_is_rekeying(active_state) && 855*e9778795SPeter Avalos packet_not_very_much_data_to_write()) 85618de8d7fSPeter Avalos channel_output_poll(); 857*e9778795SPeter Avalos if (options.rekey_interval > 0 && compat20 && 858*e9778795SPeter Avalos !ssh_packet_is_rekeying(active_state)) 85936e94dc5SPeter Avalos rekey_timeout_ms = packet_get_rekey_timeout() * 1000; 86036e94dc5SPeter Avalos else 86136e94dc5SPeter Avalos rekey_timeout_ms = 0; 86236e94dc5SPeter Avalos 86318de8d7fSPeter Avalos wait_until_can_do_something(&readset, &writeset, &max_fd, 86436e94dc5SPeter Avalos &nalloc, rekey_timeout_ms); 86518de8d7fSPeter Avalos 86618de8d7fSPeter Avalos if (received_sigterm) { 86736e94dc5SPeter Avalos logit("Exiting on signal %d", (int)received_sigterm); 86818de8d7fSPeter Avalos /* Clean up sessions, utmp, etc. */ 86918de8d7fSPeter Avalos cleanup_exit(255); 87018de8d7fSPeter Avalos } 87118de8d7fSPeter Avalos 87218de8d7fSPeter Avalos collect_children(); 873*e9778795SPeter Avalos if (!ssh_packet_is_rekeying(active_state)) 87418de8d7fSPeter Avalos channel_after_select(readset, writeset); 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 88236e94dc5SPeter Avalos free(readset); 88336e94dc5SPeter Avalos free(writeset); 88418de8d7fSPeter Avalos 88518de8d7fSPeter Avalos /* free all channels, no more reads and writes */ 88618de8d7fSPeter Avalos channel_free_all(); 88718de8d7fSPeter Avalos 88818de8d7fSPeter Avalos /* free remaining sessions, e.g. remove wtmp entries */ 88918de8d7fSPeter Avalos session_destroy_all(NULL); 89018de8d7fSPeter Avalos } 89118de8d7fSPeter Avalos 892*e9778795SPeter Avalos static int 89318de8d7fSPeter Avalos server_input_keep_alive(int type, u_int32_t seq, void *ctxt) 89418de8d7fSPeter Avalos { 89518de8d7fSPeter Avalos debug("Got %d/%u for keepalive", type, seq); 89618de8d7fSPeter Avalos /* 89718de8d7fSPeter Avalos * reset timeout, since we got a sane answer from the client. 89818de8d7fSPeter Avalos * even if this was generated by something other than 89918de8d7fSPeter Avalos * the bogus CHANNEL_REQUEST we send for keepalives. 90018de8d7fSPeter Avalos */ 90140c002afSPeter Avalos packet_set_alive_timeouts(0); 902*e9778795SPeter Avalos return 0; 90318de8d7fSPeter Avalos } 90418de8d7fSPeter Avalos 905*e9778795SPeter Avalos static int 90618de8d7fSPeter Avalos server_input_stdin_data(int type, u_int32_t seq, void *ctxt) 90718de8d7fSPeter Avalos { 90818de8d7fSPeter Avalos char *data; 90918de8d7fSPeter Avalos u_int data_len; 91018de8d7fSPeter Avalos 91118de8d7fSPeter Avalos /* Stdin data from the client. Append it to the buffer. */ 91218de8d7fSPeter Avalos /* Ignore any data if the client has closed stdin. */ 91318de8d7fSPeter Avalos if (fdin == -1) 914*e9778795SPeter Avalos return 0; 91518de8d7fSPeter Avalos data = packet_get_string(&data_len); 91618de8d7fSPeter Avalos packet_check_eom(); 91718de8d7fSPeter Avalos buffer_append(&stdin_buffer, data, data_len); 91836e94dc5SPeter Avalos explicit_bzero(data, data_len); 91936e94dc5SPeter Avalos free(data); 920*e9778795SPeter Avalos return 0; 92118de8d7fSPeter Avalos } 92218de8d7fSPeter Avalos 923*e9778795SPeter Avalos static int 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; 934*e9778795SPeter Avalos return 0; 93518de8d7fSPeter Avalos } 93618de8d7fSPeter Avalos 937*e9778795SPeter Avalos static int 93818de8d7fSPeter Avalos server_input_window_size(int type, u_int32_t seq, void *ctxt) 93918de8d7fSPeter Avalos { 94018de8d7fSPeter Avalos u_int row = packet_get_int(); 94118de8d7fSPeter Avalos u_int col = packet_get_int(); 94218de8d7fSPeter Avalos u_int xpixel = packet_get_int(); 94318de8d7fSPeter Avalos u_int ypixel = packet_get_int(); 94418de8d7fSPeter Avalos 94518de8d7fSPeter Avalos debug("Window change received."); 94618de8d7fSPeter Avalos packet_check_eom(); 94718de8d7fSPeter Avalos if (fdin != -1) 94818de8d7fSPeter Avalos pty_change_window_size(fdin, row, col, xpixel, ypixel); 949*e9778795SPeter Avalos return 0; 95018de8d7fSPeter Avalos } 95118de8d7fSPeter Avalos 95218de8d7fSPeter Avalos static Channel * 95318de8d7fSPeter Avalos server_request_direct_tcpip(void) 95418de8d7fSPeter Avalos { 95536e94dc5SPeter Avalos Channel *c = NULL; 95618de8d7fSPeter Avalos char *target, *originator; 957cb5eb4f1SPeter Avalos u_short target_port, originator_port; 95818de8d7fSPeter Avalos 95918de8d7fSPeter Avalos target = packet_get_string(NULL); 96018de8d7fSPeter Avalos target_port = packet_get_int(); 96118de8d7fSPeter Avalos originator = packet_get_string(NULL); 96218de8d7fSPeter Avalos originator_port = packet_get_int(); 96318de8d7fSPeter Avalos packet_check_eom(); 96418de8d7fSPeter Avalos 96518de8d7fSPeter Avalos debug("server_request_direct_tcpip: originator %s port %d, target %s " 96618de8d7fSPeter Avalos "port %d", originator, originator_port, target, target_port); 96718de8d7fSPeter Avalos 96836e94dc5SPeter Avalos /* XXX fine grained permissions */ 96936e94dc5SPeter Avalos if ((options.allow_tcp_forwarding & FORWARD_LOCAL) != 0 && 97036e94dc5SPeter Avalos !no_port_forwarding_flag) { 97136e94dc5SPeter Avalos c = channel_connect_to_port(target, target_port, 97218de8d7fSPeter Avalos "direct-tcpip", "direct-tcpip"); 97336e94dc5SPeter Avalos } else { 97436e94dc5SPeter Avalos logit("refused local port forward: " 97536e94dc5SPeter Avalos "originator %s port %d, target %s port %d", 97636e94dc5SPeter Avalos originator, originator_port, target, target_port); 97736e94dc5SPeter Avalos } 97818de8d7fSPeter Avalos 97936e94dc5SPeter Avalos free(originator); 98036e94dc5SPeter Avalos free(target); 98136e94dc5SPeter Avalos 98236e94dc5SPeter Avalos return c; 98336e94dc5SPeter Avalos } 98436e94dc5SPeter Avalos 98536e94dc5SPeter Avalos static Channel * 98636e94dc5SPeter Avalos server_request_direct_streamlocal(void) 98736e94dc5SPeter Avalos { 98836e94dc5SPeter Avalos Channel *c = NULL; 98936e94dc5SPeter Avalos char *target, *originator; 99036e94dc5SPeter Avalos u_short originator_port; 99136e94dc5SPeter Avalos 99236e94dc5SPeter Avalos target = packet_get_string(NULL); 99336e94dc5SPeter Avalos originator = packet_get_string(NULL); 99436e94dc5SPeter Avalos originator_port = packet_get_int(); 99536e94dc5SPeter Avalos packet_check_eom(); 99636e94dc5SPeter Avalos 99736e94dc5SPeter Avalos debug("server_request_direct_streamlocal: originator %s port %d, target %s", 99836e94dc5SPeter Avalos originator, originator_port, target); 99936e94dc5SPeter Avalos 100036e94dc5SPeter Avalos /* XXX fine grained permissions */ 100136e94dc5SPeter Avalos if ((options.allow_streamlocal_forwarding & FORWARD_LOCAL) != 0 && 100236e94dc5SPeter Avalos !no_port_forwarding_flag) { 100336e94dc5SPeter Avalos c = channel_connect_to_path(target, 100436e94dc5SPeter Avalos "direct-streamlocal@openssh.com", "direct-streamlocal"); 100536e94dc5SPeter Avalos } else { 100636e94dc5SPeter Avalos logit("refused streamlocal port forward: " 100736e94dc5SPeter Avalos "originator %s port %d, target %s", 100836e94dc5SPeter Avalos originator, originator_port, target); 100936e94dc5SPeter Avalos } 101036e94dc5SPeter Avalos 101136e94dc5SPeter Avalos free(originator); 101236e94dc5SPeter Avalos free(target); 101318de8d7fSPeter Avalos 101418de8d7fSPeter Avalos return c; 101518de8d7fSPeter Avalos } 101618de8d7fSPeter Avalos 101718de8d7fSPeter Avalos static Channel * 101818de8d7fSPeter Avalos server_request_tun(void) 101918de8d7fSPeter Avalos { 102018de8d7fSPeter Avalos Channel *c = NULL; 102118de8d7fSPeter Avalos int mode, tun; 102218de8d7fSPeter Avalos int sock; 102318de8d7fSPeter Avalos 102418de8d7fSPeter Avalos mode = packet_get_int(); 102518de8d7fSPeter Avalos switch (mode) { 102618de8d7fSPeter Avalos case SSH_TUNMODE_POINTOPOINT: 102718de8d7fSPeter Avalos case SSH_TUNMODE_ETHERNET: 102818de8d7fSPeter Avalos break; 102918de8d7fSPeter Avalos default: 103018de8d7fSPeter Avalos packet_send_debug("Unsupported tunnel device mode."); 103118de8d7fSPeter Avalos return NULL; 103218de8d7fSPeter Avalos } 103318de8d7fSPeter Avalos if ((options.permit_tun & mode) == 0) { 103418de8d7fSPeter Avalos packet_send_debug("Server has rejected tunnel device " 103518de8d7fSPeter Avalos "forwarding"); 103618de8d7fSPeter Avalos return NULL; 103718de8d7fSPeter Avalos } 103818de8d7fSPeter Avalos 103918de8d7fSPeter Avalos tun = packet_get_int(); 104018de8d7fSPeter Avalos if (forced_tun_device != -1) { 104118de8d7fSPeter Avalos if (tun != SSH_TUNID_ANY && forced_tun_device != tun) 104218de8d7fSPeter Avalos goto done; 104318de8d7fSPeter Avalos tun = forced_tun_device; 104418de8d7fSPeter Avalos } 104518de8d7fSPeter Avalos sock = tun_open(tun, mode); 104618de8d7fSPeter Avalos if (sock < 0) 104718de8d7fSPeter Avalos goto done; 104818de8d7fSPeter Avalos c = channel_new("tun", SSH_CHANNEL_OPEN, sock, sock, -1, 104918de8d7fSPeter Avalos CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, "tun", 1); 105018de8d7fSPeter Avalos c->datagram = 1; 105118de8d7fSPeter Avalos #if defined(SSH_TUN_FILTER) 105218de8d7fSPeter Avalos if (mode == SSH_TUNMODE_POINTOPOINT) 105318de8d7fSPeter Avalos channel_register_filter(c->self, sys_tun_infilter, 105418de8d7fSPeter Avalos sys_tun_outfilter, NULL, NULL); 105518de8d7fSPeter Avalos #endif 105618de8d7fSPeter Avalos 105718de8d7fSPeter Avalos done: 105818de8d7fSPeter Avalos if (c == NULL) 105918de8d7fSPeter Avalos packet_send_debug("Failed to open the tunnel device."); 106018de8d7fSPeter Avalos return c; 106118de8d7fSPeter Avalos } 106218de8d7fSPeter Avalos 106318de8d7fSPeter Avalos static Channel * 106418de8d7fSPeter Avalos server_request_session(void) 106518de8d7fSPeter Avalos { 106618de8d7fSPeter Avalos Channel *c; 106718de8d7fSPeter Avalos 106818de8d7fSPeter Avalos debug("input_session_request"); 106918de8d7fSPeter Avalos packet_check_eom(); 107018de8d7fSPeter Avalos 107118de8d7fSPeter Avalos if (no_more_sessions) { 107218de8d7fSPeter Avalos packet_disconnect("Possible attack: attempt to open a session " 107318de8d7fSPeter Avalos "after additional sessions disabled"); 107418de8d7fSPeter Avalos } 107518de8d7fSPeter Avalos 107618de8d7fSPeter Avalos /* 107718de8d7fSPeter Avalos * A server session has no fd to read or write until a 107818de8d7fSPeter Avalos * CHANNEL_REQUEST for a shell is made, so we set the type to 107918de8d7fSPeter Avalos * SSH_CHANNEL_LARVAL. Additionally, a callback for handling all 108018de8d7fSPeter Avalos * CHANNEL_REQUEST messages is registered. 108118de8d7fSPeter Avalos */ 108218de8d7fSPeter Avalos c = channel_new("session", SSH_CHANNEL_LARVAL, 108318de8d7fSPeter Avalos -1, -1, -1, /*window size*/0, CHAN_SES_PACKET_DEFAULT, 108418de8d7fSPeter Avalos 0, "server-session", 1); 108518de8d7fSPeter Avalos if (session_open(the_authctxt, c->self) != 1) { 108618de8d7fSPeter Avalos debug("session open failed, free channel %d", c->self); 108718de8d7fSPeter Avalos channel_free(c); 108818de8d7fSPeter Avalos return NULL; 108918de8d7fSPeter Avalos } 109018de8d7fSPeter Avalos channel_register_cleanup(c->self, session_close_by_channel, 0); 109118de8d7fSPeter Avalos return c; 109218de8d7fSPeter Avalos } 109318de8d7fSPeter Avalos 1094*e9778795SPeter Avalos static int 109518de8d7fSPeter Avalos server_input_channel_open(int type, u_int32_t seq, void *ctxt) 109618de8d7fSPeter Avalos { 109718de8d7fSPeter Avalos Channel *c = NULL; 109818de8d7fSPeter Avalos char *ctype; 109918de8d7fSPeter Avalos int rchan; 110018de8d7fSPeter Avalos u_int rmaxpack, rwindow, len; 110118de8d7fSPeter Avalos 110218de8d7fSPeter Avalos ctype = packet_get_string(&len); 110318de8d7fSPeter Avalos rchan = packet_get_int(); 110418de8d7fSPeter Avalos rwindow = packet_get_int(); 110518de8d7fSPeter Avalos rmaxpack = packet_get_int(); 110618de8d7fSPeter Avalos 110718de8d7fSPeter Avalos debug("server_input_channel_open: ctype %s rchan %d win %d max %d", 110818de8d7fSPeter Avalos ctype, rchan, rwindow, rmaxpack); 110918de8d7fSPeter Avalos 111018de8d7fSPeter Avalos if (strcmp(ctype, "session") == 0) { 111118de8d7fSPeter Avalos c = server_request_session(); 111218de8d7fSPeter Avalos } else if (strcmp(ctype, "direct-tcpip") == 0) { 111318de8d7fSPeter Avalos c = server_request_direct_tcpip(); 111436e94dc5SPeter Avalos } else if (strcmp(ctype, "direct-streamlocal@openssh.com") == 0) { 111536e94dc5SPeter Avalos c = server_request_direct_streamlocal(); 111618de8d7fSPeter Avalos } else if (strcmp(ctype, "tun@openssh.com") == 0) { 111718de8d7fSPeter Avalos c = server_request_tun(); 111818de8d7fSPeter Avalos } 111918de8d7fSPeter Avalos if (c != NULL) { 112018de8d7fSPeter Avalos debug("server_input_channel_open: confirm %s", ctype); 112118de8d7fSPeter Avalos c->remote_id = rchan; 112218de8d7fSPeter Avalos c->remote_window = rwindow; 112318de8d7fSPeter Avalos c->remote_maxpacket = rmaxpack; 112418de8d7fSPeter Avalos if (c->type != SSH_CHANNEL_CONNECTING) { 112518de8d7fSPeter Avalos packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION); 112618de8d7fSPeter Avalos packet_put_int(c->remote_id); 112718de8d7fSPeter Avalos packet_put_int(c->self); 112818de8d7fSPeter Avalos packet_put_int(c->local_window); 112918de8d7fSPeter Avalos packet_put_int(c->local_maxpacket); 113018de8d7fSPeter Avalos packet_send(); 113118de8d7fSPeter Avalos } 113218de8d7fSPeter Avalos } else { 113318de8d7fSPeter Avalos debug("server_input_channel_open: failure %s", ctype); 113418de8d7fSPeter Avalos packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE); 113518de8d7fSPeter Avalos packet_put_int(rchan); 113618de8d7fSPeter Avalos packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED); 113718de8d7fSPeter Avalos if (!(datafellows & SSH_BUG_OPENFAILURE)) { 113818de8d7fSPeter Avalos packet_put_cstring("open failed"); 113918de8d7fSPeter Avalos packet_put_cstring(""); 114018de8d7fSPeter Avalos } 114118de8d7fSPeter Avalos packet_send(); 114218de8d7fSPeter Avalos } 114336e94dc5SPeter Avalos free(ctype); 1144*e9778795SPeter Avalos return 0; 114518de8d7fSPeter Avalos } 114618de8d7fSPeter Avalos 1147*e9778795SPeter Avalos static int 1148*e9778795SPeter Avalos server_input_hostkeys_prove(struct sshbuf **respp) 1149*e9778795SPeter Avalos { 1150*e9778795SPeter Avalos struct ssh *ssh = active_state; /* XXX */ 1151*e9778795SPeter Avalos struct sshbuf *resp = NULL; 1152*e9778795SPeter Avalos struct sshbuf *sigbuf = NULL; 1153*e9778795SPeter Avalos struct sshkey *key = NULL, *key_pub = NULL, *key_prv = NULL; 1154*e9778795SPeter Avalos int r, ndx, success = 0; 1155*e9778795SPeter Avalos const u_char *blob; 1156*e9778795SPeter Avalos u_char *sig = 0; 1157*e9778795SPeter Avalos size_t blen, slen; 1158*e9778795SPeter Avalos 1159*e9778795SPeter Avalos if ((resp = sshbuf_new()) == NULL || (sigbuf = sshbuf_new()) == NULL) 1160*e9778795SPeter Avalos fatal("%s: sshbuf_new", __func__); 1161*e9778795SPeter Avalos 1162*e9778795SPeter Avalos while (ssh_packet_remaining(ssh) > 0) { 1163*e9778795SPeter Avalos sshkey_free(key); 1164*e9778795SPeter Avalos key = NULL; 1165*e9778795SPeter Avalos if ((r = sshpkt_get_string_direct(ssh, &blob, &blen)) != 0 || 1166*e9778795SPeter Avalos (r = sshkey_from_blob(blob, blen, &key)) != 0) { 1167*e9778795SPeter Avalos error("%s: couldn't parse key: %s", 1168*e9778795SPeter Avalos __func__, ssh_err(r)); 1169*e9778795SPeter Avalos goto out; 1170*e9778795SPeter Avalos } 1171*e9778795SPeter Avalos /* 1172*e9778795SPeter Avalos * Better check that this is actually one of our hostkeys 1173*e9778795SPeter Avalos * before attempting to sign anything with it. 1174*e9778795SPeter Avalos */ 1175*e9778795SPeter Avalos if ((ndx = ssh->kex->host_key_index(key, 1, ssh)) == -1) { 1176*e9778795SPeter Avalos error("%s: unknown host %s key", 1177*e9778795SPeter Avalos __func__, sshkey_type(key)); 1178*e9778795SPeter Avalos goto out; 1179*e9778795SPeter Avalos } 1180*e9778795SPeter Avalos /* 1181*e9778795SPeter Avalos * XXX refactor: make kex->sign just use an index rather 1182*e9778795SPeter Avalos * than passing in public and private keys 1183*e9778795SPeter Avalos */ 1184*e9778795SPeter Avalos if ((key_prv = get_hostkey_by_index(ndx)) == NULL && 1185*e9778795SPeter Avalos (key_pub = get_hostkey_public_by_index(ndx, ssh)) == NULL) { 1186*e9778795SPeter Avalos error("%s: can't retrieve hostkey %d", __func__, ndx); 1187*e9778795SPeter Avalos goto out; 1188*e9778795SPeter Avalos } 1189*e9778795SPeter Avalos sshbuf_reset(sigbuf); 1190*e9778795SPeter Avalos free(sig); 1191*e9778795SPeter Avalos sig = NULL; 1192*e9778795SPeter Avalos if ((r = sshbuf_put_cstring(sigbuf, 1193*e9778795SPeter Avalos "hostkeys-prove-00@openssh.com")) != 0 || 1194*e9778795SPeter Avalos (r = sshbuf_put_string(sigbuf, 1195*e9778795SPeter Avalos ssh->kex->session_id, ssh->kex->session_id_len)) != 0 || 1196*e9778795SPeter Avalos (r = sshkey_puts(key, sigbuf)) != 0 || 1197*e9778795SPeter Avalos (r = ssh->kex->sign(key_prv, key_pub, &sig, &slen, 1198*e9778795SPeter Avalos sshbuf_ptr(sigbuf), sshbuf_len(sigbuf), NULL, 0)) != 0 || 1199*e9778795SPeter Avalos (r = sshbuf_put_string(resp, sig, slen)) != 0) { 1200*e9778795SPeter Avalos error("%s: couldn't prepare signature: %s", 1201*e9778795SPeter Avalos __func__, ssh_err(r)); 1202*e9778795SPeter Avalos goto out; 1203*e9778795SPeter Avalos } 1204*e9778795SPeter Avalos } 1205*e9778795SPeter Avalos /* Success */ 1206*e9778795SPeter Avalos *respp = resp; 1207*e9778795SPeter Avalos resp = NULL; /* don't free it */ 1208*e9778795SPeter Avalos success = 1; 1209*e9778795SPeter Avalos out: 1210*e9778795SPeter Avalos free(sig); 1211*e9778795SPeter Avalos sshbuf_free(resp); 1212*e9778795SPeter Avalos sshbuf_free(sigbuf); 1213*e9778795SPeter Avalos sshkey_free(key); 1214*e9778795SPeter Avalos return success; 1215*e9778795SPeter Avalos } 1216*e9778795SPeter Avalos 1217*e9778795SPeter Avalos static int 121818de8d7fSPeter Avalos server_input_global_request(int type, u_int32_t seq, void *ctxt) 121918de8d7fSPeter Avalos { 122018de8d7fSPeter Avalos char *rtype; 122118de8d7fSPeter Avalos int want_reply; 1222*e9778795SPeter Avalos int r, success = 0, allocated_listen_port = 0; 1223*e9778795SPeter Avalos struct sshbuf *resp = NULL; 122418de8d7fSPeter Avalos 122518de8d7fSPeter Avalos rtype = packet_get_string(NULL); 122618de8d7fSPeter Avalos want_reply = packet_get_char(); 122718de8d7fSPeter Avalos debug("server_input_global_request: rtype %s want_reply %d", rtype, want_reply); 122818de8d7fSPeter Avalos 122918de8d7fSPeter Avalos /* -R style forwarding */ 123018de8d7fSPeter Avalos if (strcmp(rtype, "tcpip-forward") == 0) { 123118de8d7fSPeter Avalos struct passwd *pw; 123236e94dc5SPeter Avalos struct Forward fwd; 123318de8d7fSPeter Avalos 123418de8d7fSPeter Avalos pw = the_authctxt->pw; 123518de8d7fSPeter Avalos if (pw == NULL || !the_authctxt->valid) 123618de8d7fSPeter Avalos fatal("server_input_global_request: no/invalid user"); 123736e94dc5SPeter Avalos memset(&fwd, 0, sizeof(fwd)); 123836e94dc5SPeter Avalos fwd.listen_host = packet_get_string(NULL); 123936e94dc5SPeter Avalos fwd.listen_port = (u_short)packet_get_int(); 124018de8d7fSPeter Avalos debug("server_input_global_request: tcpip-forward listen %s port %d", 124136e94dc5SPeter Avalos fwd.listen_host, fwd.listen_port); 124218de8d7fSPeter Avalos 124318de8d7fSPeter Avalos /* check permissions */ 124436e94dc5SPeter Avalos if ((options.allow_tcp_forwarding & FORWARD_REMOTE) == 0 || 1245cb5eb4f1SPeter Avalos no_port_forwarding_flag || 1246*e9778795SPeter Avalos (!want_reply && fwd.listen_port == 0) || 1247*e9778795SPeter Avalos (fwd.listen_port != 0 && fwd.listen_port < IPPORT_RESERVED && 1248*e9778795SPeter Avalos pw->pw_uid != 0)) { 124918de8d7fSPeter Avalos success = 0; 125018de8d7fSPeter Avalos packet_send_debug("Server has disabled port forwarding."); 125118de8d7fSPeter Avalos } else { 125218de8d7fSPeter Avalos /* Start listening on the port */ 125336e94dc5SPeter Avalos success = channel_setup_remote_fwd_listener(&fwd, 125436e94dc5SPeter Avalos &allocated_listen_port, &options.fwd_opts); 125518de8d7fSPeter Avalos } 125636e94dc5SPeter Avalos free(fwd.listen_host); 1257*e9778795SPeter Avalos if ((resp = sshbuf_new()) == NULL) 1258*e9778795SPeter Avalos fatal("%s: sshbuf_new", __func__); 1259*e9778795SPeter Avalos if (allocated_listen_port != 0 && 1260*e9778795SPeter Avalos (r = sshbuf_put_u32(resp, allocated_listen_port)) != 0) 1261*e9778795SPeter Avalos fatal("%s: sshbuf_put_u32: %s", __func__, ssh_err(r)); 126218de8d7fSPeter Avalos } else if (strcmp(rtype, "cancel-tcpip-forward") == 0) { 126336e94dc5SPeter Avalos struct Forward fwd; 126418de8d7fSPeter Avalos 126536e94dc5SPeter Avalos memset(&fwd, 0, sizeof(fwd)); 126636e94dc5SPeter Avalos fwd.listen_host = packet_get_string(NULL); 126736e94dc5SPeter Avalos fwd.listen_port = (u_short)packet_get_int(); 126818de8d7fSPeter Avalos debug("%s: cancel-tcpip-forward addr %s port %d", __func__, 126936e94dc5SPeter Avalos fwd.listen_host, fwd.listen_port); 127018de8d7fSPeter Avalos 127136e94dc5SPeter Avalos success = channel_cancel_rport_listener(&fwd); 127236e94dc5SPeter Avalos free(fwd.listen_host); 127336e94dc5SPeter Avalos } else if (strcmp(rtype, "streamlocal-forward@openssh.com") == 0) { 127436e94dc5SPeter Avalos struct Forward fwd; 127536e94dc5SPeter Avalos 127636e94dc5SPeter Avalos memset(&fwd, 0, sizeof(fwd)); 127736e94dc5SPeter Avalos fwd.listen_path = packet_get_string(NULL); 127836e94dc5SPeter Avalos debug("server_input_global_request: streamlocal-forward listen path %s", 127936e94dc5SPeter Avalos fwd.listen_path); 128036e94dc5SPeter Avalos 128136e94dc5SPeter Avalos /* check permissions */ 128236e94dc5SPeter Avalos if ((options.allow_streamlocal_forwarding & FORWARD_REMOTE) == 0 128336e94dc5SPeter Avalos || no_port_forwarding_flag) { 128436e94dc5SPeter Avalos success = 0; 128536e94dc5SPeter Avalos packet_send_debug("Server has disabled port forwarding."); 128636e94dc5SPeter Avalos } else { 128736e94dc5SPeter Avalos /* Start listening on the socket */ 128836e94dc5SPeter Avalos success = channel_setup_remote_fwd_listener( 128936e94dc5SPeter Avalos &fwd, NULL, &options.fwd_opts); 129036e94dc5SPeter Avalos } 129136e94dc5SPeter Avalos free(fwd.listen_path); 129236e94dc5SPeter Avalos } else if (strcmp(rtype, "cancel-streamlocal-forward@openssh.com") == 0) { 129336e94dc5SPeter Avalos struct Forward fwd; 129436e94dc5SPeter Avalos 129536e94dc5SPeter Avalos memset(&fwd, 0, sizeof(fwd)); 129636e94dc5SPeter Avalos fwd.listen_path = packet_get_string(NULL); 129736e94dc5SPeter Avalos debug("%s: cancel-streamlocal-forward path %s", __func__, 129836e94dc5SPeter Avalos fwd.listen_path); 129936e94dc5SPeter Avalos 130036e94dc5SPeter Avalos success = channel_cancel_rport_listener(&fwd); 130136e94dc5SPeter Avalos free(fwd.listen_path); 130218de8d7fSPeter Avalos } else if (strcmp(rtype, "no-more-sessions@openssh.com") == 0) { 130318de8d7fSPeter Avalos no_more_sessions = 1; 130418de8d7fSPeter Avalos success = 1; 1305*e9778795SPeter Avalos } else if (strcmp(rtype, "hostkeys-prove-00@openssh.com") == 0) { 1306*e9778795SPeter Avalos success = server_input_hostkeys_prove(&resp); 130718de8d7fSPeter Avalos } 130818de8d7fSPeter Avalos if (want_reply) { 130918de8d7fSPeter Avalos packet_start(success ? 131018de8d7fSPeter Avalos SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE); 1311*e9778795SPeter Avalos if (success && resp != NULL) 1312*e9778795SPeter Avalos ssh_packet_put_raw(active_state, sshbuf_ptr(resp), 1313*e9778795SPeter Avalos sshbuf_len(resp)); 131418de8d7fSPeter Avalos packet_send(); 131518de8d7fSPeter Avalos packet_write_wait(); 131618de8d7fSPeter Avalos } 131736e94dc5SPeter Avalos free(rtype); 1318*e9778795SPeter Avalos sshbuf_free(resp); 1319*e9778795SPeter Avalos return 0; 132018de8d7fSPeter Avalos } 132118de8d7fSPeter Avalos 1322*e9778795SPeter Avalos static int 132318de8d7fSPeter Avalos server_input_channel_req(int type, u_int32_t seq, void *ctxt) 132418de8d7fSPeter Avalos { 132518de8d7fSPeter Avalos Channel *c; 132618de8d7fSPeter Avalos int id, reply, success = 0; 132718de8d7fSPeter Avalos char *rtype; 132818de8d7fSPeter Avalos 132918de8d7fSPeter Avalos id = packet_get_int(); 133018de8d7fSPeter Avalos rtype = packet_get_string(NULL); 133118de8d7fSPeter Avalos reply = packet_get_char(); 133218de8d7fSPeter Avalos 133318de8d7fSPeter Avalos debug("server_input_channel_req: channel %d request %s reply %d", 133418de8d7fSPeter Avalos id, rtype, reply); 133518de8d7fSPeter Avalos 133618de8d7fSPeter Avalos if ((c = channel_lookup(id)) == NULL) 133718de8d7fSPeter Avalos packet_disconnect("server_input_channel_req: " 133818de8d7fSPeter Avalos "unknown channel %d", id); 133918de8d7fSPeter Avalos if (!strcmp(rtype, "eow@openssh.com")) { 134018de8d7fSPeter Avalos packet_check_eom(); 134118de8d7fSPeter Avalos chan_rcvd_eow(c); 134218de8d7fSPeter Avalos } else if ((c->type == SSH_CHANNEL_LARVAL || 134318de8d7fSPeter Avalos c->type == SSH_CHANNEL_OPEN) && strcmp(c->ctype, "session") == 0) 134418de8d7fSPeter Avalos success = session_input_channel_req(c, rtype); 134536e94dc5SPeter Avalos if (reply && !(c->flags & CHAN_CLOSE_SENT)) { 134618de8d7fSPeter Avalos packet_start(success ? 134718de8d7fSPeter Avalos SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE); 134818de8d7fSPeter Avalos packet_put_int(c->remote_id); 134918de8d7fSPeter Avalos packet_send(); 135018de8d7fSPeter Avalos } 135136e94dc5SPeter Avalos free(rtype); 1352*e9778795SPeter Avalos return 0; 135318de8d7fSPeter Avalos } 135418de8d7fSPeter Avalos 135518de8d7fSPeter Avalos static void 135618de8d7fSPeter Avalos server_init_dispatch_20(void) 135718de8d7fSPeter Avalos { 135818de8d7fSPeter Avalos debug("server_init_dispatch_20"); 135918de8d7fSPeter Avalos dispatch_init(&dispatch_protocol_error); 136018de8d7fSPeter Avalos dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose); 136118de8d7fSPeter Avalos dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data); 136218de8d7fSPeter Avalos dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof); 136318de8d7fSPeter Avalos dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data); 136418de8d7fSPeter Avalos dispatch_set(SSH2_MSG_CHANNEL_OPEN, &server_input_channel_open); 136518de8d7fSPeter Avalos dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation); 136618de8d7fSPeter Avalos dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure); 136718de8d7fSPeter Avalos dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &server_input_channel_req); 136818de8d7fSPeter Avalos dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust); 136918de8d7fSPeter Avalos dispatch_set(SSH2_MSG_GLOBAL_REQUEST, &server_input_global_request); 137018de8d7fSPeter Avalos /* client_alive */ 1371cb5eb4f1SPeter Avalos dispatch_set(SSH2_MSG_CHANNEL_SUCCESS, &server_input_keep_alive); 1372cb5eb4f1SPeter Avalos dispatch_set(SSH2_MSG_CHANNEL_FAILURE, &server_input_keep_alive); 137318de8d7fSPeter Avalos dispatch_set(SSH2_MSG_REQUEST_SUCCESS, &server_input_keep_alive); 137418de8d7fSPeter Avalos dispatch_set(SSH2_MSG_REQUEST_FAILURE, &server_input_keep_alive); 137518de8d7fSPeter Avalos /* rekeying */ 137618de8d7fSPeter Avalos dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit); 137718de8d7fSPeter Avalos } 137818de8d7fSPeter Avalos static void 137918de8d7fSPeter Avalos server_init_dispatch_13(void) 138018de8d7fSPeter Avalos { 138118de8d7fSPeter Avalos debug("server_init_dispatch_13"); 138218de8d7fSPeter Avalos dispatch_init(NULL); 138318de8d7fSPeter Avalos dispatch_set(SSH_CMSG_EOF, &server_input_eof); 138418de8d7fSPeter Avalos dispatch_set(SSH_CMSG_STDIN_DATA, &server_input_stdin_data); 138518de8d7fSPeter Avalos dispatch_set(SSH_CMSG_WINDOW_SIZE, &server_input_window_size); 138618de8d7fSPeter Avalos dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close); 138718de8d7fSPeter Avalos dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation); 138818de8d7fSPeter Avalos dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data); 138918de8d7fSPeter Avalos dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation); 139018de8d7fSPeter Avalos dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure); 139118de8d7fSPeter Avalos dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open); 139218de8d7fSPeter Avalos } 139318de8d7fSPeter Avalos static void 139418de8d7fSPeter Avalos server_init_dispatch_15(void) 139518de8d7fSPeter Avalos { 139618de8d7fSPeter Avalos server_init_dispatch_13(); 139718de8d7fSPeter Avalos debug("server_init_dispatch_15"); 139818de8d7fSPeter Avalos dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof); 139918de8d7fSPeter Avalos dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_oclose); 140018de8d7fSPeter Avalos } 140118de8d7fSPeter Avalos static void 140218de8d7fSPeter Avalos server_init_dispatch(void) 140318de8d7fSPeter Avalos { 140418de8d7fSPeter Avalos if (compat20) 140518de8d7fSPeter Avalos server_init_dispatch_20(); 140618de8d7fSPeter Avalos else if (compat13) 140718de8d7fSPeter Avalos server_init_dispatch_13(); 140818de8d7fSPeter Avalos else 140918de8d7fSPeter Avalos server_init_dispatch_15(); 141018de8d7fSPeter Avalos } 1411