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Diffstat (limited to 'clientloop.c')
| -rw-r--r-- | clientloop.c | 924 |
1 files changed, 924 insertions, 0 deletions
diff --git a/clientloop.c b/clientloop.c new file mode 100644 index 00000000..43373b72 --- /dev/null +++ b/clientloop.c @@ -0,0 +1,924 @@ +/* + +clientloop.c + +Author: Tatu Ylonen <ylo@cs.hut.fi> + +Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland + All rights reserved + + +Created: Sat Sep 23 12:23:57 1995 ylo + +The main loop for the interactive session (client side). + +*/ + +#include "includes.h" +RCSID("$Id: clientloop.c,v 1.1 1999/10/27 03:42:44 damien Exp $"); + +#include "xmalloc.h" +#include "ssh.h" +#include "packet.h" +#include "buffer.h" +#include "authfd.h" + +/* Flag indicating whether quiet mode is on. */ +extern int quiet_flag; + +/* Flag indicating that stdin should be redirected from /dev/null. */ +extern int stdin_null_flag; + +/* Name of the host we are connecting to. This is the name given on the + command line, or the HostName specified for the user-supplied name + in a configuration file. */ +extern char *host; + +/* Flag to indicate that we have received a window change signal which has + not yet been processed. This will cause a message indicating the new + window size to be sent to the server a little later. This is volatile + because this is updated in a signal handler. */ +static volatile int received_window_change_signal = 0; + +/* Terminal modes, as saved by enter_raw_mode. */ +static struct termios saved_tio; + +/* Flag indicating whether we are in raw mode. This is used by enter_raw_mode + and leave_raw_mode. */ +static int in_raw_mode = 0; + +/* Flag indicating whether the user\'s terminal is in non-blocking mode. */ +static int in_non_blocking_mode = 0; + +/* Common data for the client loop code. */ +static int escape_pending; /* Last character was the escape character */ +static int last_was_cr; /* Last character was a newline. */ +static int exit_status; /* Used to store the exit status of the command. */ +static int stdin_eof; /* EOF has been encountered on standard error. */ +static Buffer stdin_buffer; /* Buffer for stdin data. */ +static Buffer stdout_buffer; /* Buffer for stdout data. */ +static Buffer stderr_buffer; /* Buffer for stderr data. */ +static unsigned int buffer_high; /* Soft max buffer size. */ +static int max_fd; /* Maximum file descriptor number in select(). */ +static int connection_in; /* Connection to server (input). */ +static int connection_out; /* Connection to server (output). */ +static unsigned long stdin_bytes, stdout_bytes, stderr_bytes; +static int quit_pending; /* Set to non-zero to quit the client loop. */ +static int escape_char; /* Escape character. */ + +/* Returns the user\'s terminal to normal mode if it had been put in raw + mode. */ + +void leave_raw_mode() +{ + if (!in_raw_mode) + return; + in_raw_mode = 0; + if (tcsetattr(fileno(stdin), TCSADRAIN, &saved_tio) < 0) + perror("tcsetattr"); + + fatal_remove_cleanup((void (*)(void *))leave_raw_mode, NULL); +} + +/* Puts the user\'s terminal in raw mode. */ + +void enter_raw_mode() +{ + struct termios tio; + + if (tcgetattr(fileno(stdin), &tio) < 0) + perror("tcgetattr"); + saved_tio = tio; + tio.c_iflag |= IGNPAR; + tio.c_iflag &= ~(ISTRIP|INLCR|IGNCR|ICRNL|IXON|IXANY|IXOFF); + tio.c_lflag &= ~(ISIG|ICANON|ECHO|ECHOE|ECHOK|ECHONL); +#ifdef IEXTEN + tio.c_lflag &= ~IEXTEN; +#endif /* IEXTEN */ + tio.c_oflag &= ~OPOST; + tio.c_cc[VMIN] = 1; + tio.c_cc[VTIME] = 0; + if (tcsetattr(fileno(stdin), TCSADRAIN, &tio) < 0) + perror("tcsetattr"); + in_raw_mode = 1; + + fatal_add_cleanup((void (*)(void *))leave_raw_mode, NULL); +} + +/* Puts stdin terminal in non-blocking mode. */ + +/* Restores stdin to blocking mode. */ + +void leave_non_blocking() +{ + if (in_non_blocking_mode) + { + (void)fcntl(fileno(stdin), F_SETFL, 0); + in_non_blocking_mode = 0; + fatal_remove_cleanup((void (*)(void *))leave_non_blocking, NULL); + } +} + +void enter_non_blocking() +{ + in_non_blocking_mode = 1; + (void)fcntl(fileno(stdin), F_SETFL, O_NONBLOCK); + fatal_add_cleanup((void (*)(void *))leave_non_blocking, NULL); +} + +/* Signal handler for the window change signal (SIGWINCH). This just + sets a flag indicating that the window has changed. */ + +void window_change_handler(int sig) +{ + received_window_change_signal = 1; + signal(SIGWINCH, window_change_handler); +} + +/* Signal handler for signals that cause the program to terminate. These + signals must be trapped to restore terminal modes. */ + +void signal_handler(int sig) +{ + if (in_raw_mode) + leave_raw_mode(); + if (in_non_blocking_mode) + leave_non_blocking(); + channel_stop_listening(); + packet_close(); + fatal("Killed by signal %d.", sig); +} + +/* Returns current time in seconds from Jan 1, 1970 with the maximum available + resolution. */ + +double get_current_time() +{ + struct timeval tv; + gettimeofday(&tv, NULL); + return (double)tv.tv_sec + (double)tv.tv_usec / 1000000.0; +} + +/* This is called when the interactive is entered. This checks if there + is an EOF coming on stdin. We must check this explicitly, as select() + does not appear to wake up when redirecting from /dev/null. */ + +void client_check_initial_eof_on_stdin() +{ + int len; + char buf[1]; + + /* If standard input is to be "redirected from /dev/null", we simply + mark that we have seen an EOF and send an EOF message to the server. + Otherwise, we try to read a single character; it appears that for some + files, such /dev/null, select() never wakes up for read for this + descriptor, which means that we never get EOF. This way we will get + the EOF if stdin comes from /dev/null or similar. */ + if (stdin_null_flag) + { + /* Fake EOF on stdin. */ + debug("Sending eof."); + stdin_eof = 1; + packet_start(SSH_CMSG_EOF); + packet_send(); + } + else + { + /* Enter non-blocking mode for stdin. */ + enter_non_blocking(); + + /* Check for immediate EOF on stdin. */ + len = read(fileno(stdin), buf, 1); + if (len == 0) + { + /* EOF. Record that we have seen it and send EOF to server. */ + debug("Sending eof."); + stdin_eof = 1; + packet_start(SSH_CMSG_EOF); + packet_send(); + } + else + if (len > 0) + { + /* Got data. We must store the data in the buffer, and also + process it as an escape character if appropriate. */ + if ((unsigned char)buf[0] == escape_char) + escape_pending = 1; + else + { + buffer_append(&stdin_buffer, buf, 1); + stdin_bytes += 1; + } + } + + /* Leave non-blocking mode. */ + leave_non_blocking(); + } +} + +/* Get packets from the connection input buffer, and process them as long + as there are packets available. */ + +void client_process_buffered_input_packets() +{ + int type; + char *data; + unsigned int data_len; + int payload_len; + + /* Process any buffered packets from the server. */ + while (!quit_pending && (type = packet_read_poll(&payload_len)) != SSH_MSG_NONE) + { + switch (type) + { + + case SSH_SMSG_STDOUT_DATA: + data = packet_get_string(&data_len); + packet_integrity_check(payload_len, 4 + data_len, type); + buffer_append(&stdout_buffer, data, data_len); + stdout_bytes += data_len; + memset(data, 0, data_len); + xfree(data); + break; + + case SSH_SMSG_STDERR_DATA: + data = packet_get_string(&data_len); + packet_integrity_check(payload_len, 4 + data_len, type); + buffer_append(&stderr_buffer, data, data_len); + stdout_bytes += data_len; + memset(data, 0, data_len); + xfree(data); + break; + + case SSH_SMSG_EXITSTATUS: + packet_integrity_check(payload_len, 4, type); + exit_status = packet_get_int(); + /* Acknowledge the exit. */ + packet_start(SSH_CMSG_EXIT_CONFIRMATION); + packet_send(); + /* Must wait for packet to be sent since we are exiting the + loop. */ + packet_write_wait(); + /* Flag that we want to exit. */ + quit_pending = 1; + break; + + case SSH_SMSG_X11_OPEN: + x11_input_open(payload_len); + break; + + case SSH_MSG_PORT_OPEN: + channel_input_port_open(payload_len); + break; + + case SSH_SMSG_AGENT_OPEN: + packet_integrity_check(payload_len, 4, type); + auth_input_open_request(); + break; + + case SSH_MSG_CHANNEL_OPEN_CONFIRMATION: + packet_integrity_check(payload_len, 4 + 4, type); + channel_input_open_confirmation(); + break; + + case SSH_MSG_CHANNEL_OPEN_FAILURE: + packet_integrity_check(payload_len, 4, type); + channel_input_open_failure(); + break; + + case SSH_MSG_CHANNEL_DATA: + channel_input_data(payload_len); + break; + + case SSH_MSG_CHANNEL_CLOSE: + packet_integrity_check(payload_len, 4, type); + channel_input_close(); + break; + + case SSH_MSG_CHANNEL_CLOSE_CONFIRMATION: + packet_integrity_check(payload_len, 4, type); + channel_input_close_confirmation(); + break; + + default: + /* Any unknown packets received during the actual session + cause the session to terminate. This is intended to make + debugging easier since no confirmations are sent. Any + compatible protocol extensions must be negotiated during + the preparatory phase. */ + packet_disconnect("Protocol error during session: type %d", + type); + } + } +} + +/* Make packets from buffered stdin data, and buffer them for sending to + the connection. */ + +void client_make_packets_from_stdin_data() +{ + unsigned int len; + + /* Send buffered stdin data to the server. */ + while (buffer_len(&stdin_buffer) > 0 && + packet_not_very_much_data_to_write()) + { + len = buffer_len(&stdin_buffer); + if (len > 32768) + len = 32768; /* Keep the packets at reasonable size. */ + packet_start(SSH_CMSG_STDIN_DATA); + packet_put_string(buffer_ptr(&stdin_buffer), len); + packet_send(); + buffer_consume(&stdin_buffer, len); + /* If we have a pending EOF, send it now. */ + if (stdin_eof && buffer_len(&stdin_buffer) == 0) + { + packet_start(SSH_CMSG_EOF); + packet_send(); + } + } +} + +/* Checks if the client window has changed, and sends a packet about it to + the server if so. The actual change is detected elsewhere (by a software + interrupt on Unix); this just checks the flag and sends a message if + appropriate. */ + +void client_check_window_change() +{ + /* Send possible window change message to the server. */ + if (received_window_change_signal) + { + struct winsize ws; + + /* Clear the window change indicator. */ + received_window_change_signal = 0; + + /* Read new window size. */ + if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) >= 0) + { + /* Successful, send the packet now. */ + packet_start(SSH_CMSG_WINDOW_SIZE); + packet_put_int(ws.ws_row); + packet_put_int(ws.ws_col); + packet_put_int(ws.ws_xpixel); + packet_put_int(ws.ws_ypixel); + packet_send(); + } + } +} + +/* Waits until the client can do something (some data becomes available on + one of the file descriptors). */ + +void client_wait_until_can_do_something(fd_set *readset, fd_set *writeset) +{ + /* Initialize select masks. */ + FD_ZERO(readset); + + /* Read from the connection, unless our buffers are full. */ + if (buffer_len(&stdout_buffer) < buffer_high && + buffer_len(&stderr_buffer) < buffer_high && + channel_not_very_much_buffered_data()) + FD_SET(connection_in, readset); + + /* Read from stdin, unless we have seen EOF or have very much buffered + data to send to the server. */ + if (!stdin_eof && packet_not_very_much_data_to_write()) + FD_SET(fileno(stdin), readset); + + FD_ZERO(writeset); + + /* Add any selections by the channel mechanism. */ + channel_prepare_select(readset, writeset); + + /* Select server connection if have data to write to the server. */ + if (packet_have_data_to_write()) + FD_SET(connection_out, writeset); + + /* Select stdout if have data in buffer. */ + if (buffer_len(&stdout_buffer) > 0) + FD_SET(fileno(stdout), writeset); + + /* Select stderr if have data in buffer. */ + if (buffer_len(&stderr_buffer) > 0) + FD_SET(fileno(stderr), writeset); + + /* Update maximum file descriptor number, if appropriate. */ + if (channel_max_fd() > max_fd) + max_fd = channel_max_fd(); + + /* Wait for something to happen. This will suspend the process until + some selected descriptor can be read, written, or has some other + event pending. Note: if you want to implement SSH_MSG_IGNORE + messages to fool traffic analysis, this might be the place to do + it: just have a random timeout for the select, and send a random + SSH_MSG_IGNORE packet when the timeout expires. */ + if (select(max_fd + 1, readset, writeset, NULL, NULL) < 0) + { + char buf[100]; + /* Some systems fail to clear these automatically. */ + FD_ZERO(readset); + FD_ZERO(writeset); + if (errno == EINTR) + return; + /* Note: we might still have data in the buffers. */ + snprintf(buf, sizeof buf, "select: %s\r\n", strerror(errno)); + buffer_append(&stderr_buffer, buf, strlen(buf)); + stderr_bytes += strlen(buf); + quit_pending = 1; + } +} + +void client_suspend_self() +{ + struct winsize oldws, newws; + + /* Flush stdout and stderr buffers. */ + if (buffer_len(&stdout_buffer) > 0) + write(fileno(stdout), + buffer_ptr(&stdout_buffer), + buffer_len(&stdout_buffer)); + if (buffer_len(&stderr_buffer) > 0) + write(fileno(stderr), + buffer_ptr(&stderr_buffer), + buffer_len(&stderr_buffer)); + + /* Leave raw mode. */ + leave_raw_mode(); + + /* Free (and clear) the buffer to reduce the + amount of data that gets written to swap. */ + buffer_free(&stdin_buffer); + buffer_free(&stdout_buffer); + buffer_free(&stderr_buffer); + + /* Save old window size. */ + ioctl(fileno(stdin), TIOCGWINSZ, &oldws); + + /* Send the suspend signal to the program + itself. */ + kill(getpid(), SIGTSTP); + + /* Check if the window size has changed. */ + if (ioctl(fileno(stdin), TIOCGWINSZ, &newws) >= 0 && + (oldws.ws_row != newws.ws_row || oldws.ws_col != newws.ws_col || + oldws.ws_xpixel != newws.ws_xpixel || + oldws.ws_ypixel != newws.ws_ypixel)) + received_window_change_signal = 1; + + /* OK, we have been continued by the user. + Reinitialize buffers. */ + buffer_init(&stdin_buffer); + buffer_init(&stdout_buffer); + buffer_init(&stderr_buffer); + + /* Re-enter raw mode. */ + enter_raw_mode(); +} + +void client_process_input(fd_set *readset) +{ + int len, pid; + char buf[8192], *s; + + /* Read input from the server, and add any such data to the buffer of the + packet subsystem. */ + if (FD_ISSET(connection_in, readset)) + { + /* Read as much as possible. */ + len = read(connection_in, buf, sizeof(buf)); + if (len == 0) + { + /* Received EOF. The remote host has closed the connection. */ + snprintf(buf, sizeof buf, "Connection to %.300s closed by remote host.\r\n", + host); + buffer_append(&stderr_buffer, buf, strlen(buf)); + stderr_bytes += strlen(buf); + quit_pending = 1; + return; + } + + /* There is a kernel bug on Solaris that causes select to sometimes + wake up even though there is no data available. */ + if (len < 0 && errno == EAGAIN) + len = 0; + + if (len < 0) + { + /* An error has encountered. Perhaps there is a network + problem. */ + snprintf(buf, sizeof buf, "Read from remote host %.300s: %.100s\r\n", + host, strerror(errno)); + buffer_append(&stderr_buffer, buf, strlen(buf)); + stderr_bytes += strlen(buf); + quit_pending = 1; + return; + } + packet_process_incoming(buf, len); + } + + /* Read input from stdin. */ + if (FD_ISSET(fileno(stdin), readset)) + { + /* Read as much as possible. */ + len = read(fileno(stdin), buf, sizeof(buf)); + if (len <= 0) + { + /* Received EOF or error. They are treated similarly, + except that an error message is printed if it was + an error condition. */ + if (len < 0) + { + snprintf(buf, sizeof buf, "read: %.100s\r\n", strerror(errno)); + buffer_append(&stderr_buffer, buf, strlen(buf)); + stderr_bytes += strlen(buf); + } + /* Mark that we have seen EOF. */ + stdin_eof = 1; + /* Send an EOF message to the server unless there is data + in the buffer. If there is data in the buffer, no message + will be sent now. Code elsewhere will send the EOF + when the buffer becomes empty if stdin_eof is set. */ + if (buffer_len(&stdin_buffer) == 0) + { + packet_start(SSH_CMSG_EOF); + packet_send(); + } + } + else + if (escape_char == -1) + { + /* Normal successful read, and no escape character. Just + append the data to buffer. */ + buffer_append(&stdin_buffer, buf, len); + stdin_bytes += len; + } + else + { + /* Normal, successful read. But we have an escape character + and have to process the characters one by one. */ + unsigned int i; + for (i = 0; i < len; i++) + { + unsigned char ch; + /* Get one character at a time. */ + ch = buf[i]; + + /* Check if we have a pending escape character. */ + if (escape_pending) + { + /* We have previously seen an escape character. */ + /* Clear the flag now. */ + escape_pending = 0; + /* Process the escaped character. */ + switch (ch) + { + case '.': + /* Terminate the connection. */ + snprintf(buf, sizeof buf, "%c.\r\n", escape_char); + buffer_append(&stderr_buffer, buf, strlen(buf)); + stderr_bytes += strlen(buf); + quit_pending = 1; + return; + + case 'Z' - 64: + /* Suspend the program. */ + /* Print a message to that effect to the user. */ + snprintf(buf, sizeof buf, "%c^Z\r\n", escape_char); + buffer_append(&stderr_buffer, buf, strlen(buf)); + stderr_bytes += strlen(buf); + + /* Restore terminal modes and suspend. */ + client_suspend_self(); + + /* We have been continued. */ + continue; + + case '&': + /* Detach the program (continue to serve connections, + but put in background and no more new + connections). */ + if (!stdin_eof) + { + /* Sending SSH_CMSG_EOF alone does not always + appear to be enough. So we try to send an + EOF character first. */ + packet_start(SSH_CMSG_STDIN_DATA); + packet_put_string("\004", 1); + packet_send(); + /* Close stdin. */ + stdin_eof = 1; + if (buffer_len(&stdin_buffer) == 0) + { + packet_start(SSH_CMSG_EOF); + packet_send(); + } + } + /* Restore tty modes. */ + leave_raw_mode(); + + /* Stop listening for new connections. */ + channel_stop_listening(); + + printf("%c& [backgrounded]\n", escape_char); + + /* Fork into background. */ + pid = fork(); + if (pid < 0) + { + error("fork: %.100s", strerror(errno)); + continue; + } + if (pid != 0) + { /* This is the parent. */ + /* The parent just exits. */ + exit(0); + } + + /* The child continues serving connections. */ + continue; + + case '?': + snprintf(buf, sizeof buf, "%c?\r\n\ +Supported escape sequences:\r\n\ +~. - terminate connection\r\n\ +~^Z - suspend ssh\r\n\ +~# - list forwarded connections\r\n\ +~& - background ssh (when waiting for connections to terminate)\r\n\ +~? - this message\r\n\ +~~ - send the escape character by typing it twice\r\n\ +(Note that escapes are only recognized immediately after newline.)\r\n", + escape_char); + buffer_append(&stderr_buffer, buf, strlen(buf)); + continue; + + case '#': + snprintf(buf, sizeof buf, "%c#\r\n", escape_char); + buffer_append(&stderr_buffer, buf, strlen(buf)); + s = channel_open_message(); + buffer_append(&stderr_buffer, s, strlen(s)); + xfree(s); + continue; + + default: + if (ch != escape_char) + { + /* Escape character followed by non-special + character. Append both to the input + buffer. */ + buf[0] = escape_char; + buf[1] = ch; + buffer_append(&stdin_buffer, buf, 2); + stdin_bytes += 2; + continue; + } + /* Note that escape character typed twice falls through + here; the latter gets processed as a normal + character below. */ + break; + } + } + else + { + /* The previous character was not an escape char. + Check if this is an escape. */ + if (last_was_cr && ch == escape_char) + { + /* It is. Set the flag and continue to next + character. */ + escape_pending = 1; + continue; + } + } + + /* Normal character. Record whether it was a newline, + and append it to the buffer. */ + last_was_cr = (ch == '\r' || ch == '\n'); + buf[0] = ch; + buffer_append(&stdin_buffer, buf, 1); + stdin_bytes += 1; + continue; + } + } + } +} + +void client_process_output(fd_set *writeset) +{ + int len; + char buf[100]; + + /* Write buffered output to stdout. */ + if (FD_ISSET(fileno(stdout), writeset)) + { + /* Write as much data as possible. */ + len = write(fileno(stdout), buffer_ptr(&stdout_buffer), + buffer_len(&stdout_buffer)); + if (len <= 0) + { + if (errno == EAGAIN) + len = 0; + else + { + /* An error or EOF was encountered. Put an error message + to stderr buffer. */ + snprintf(buf, sizeof buf, "write stdout: %.50s\r\n", strerror(errno)); + buffer_append(&stderr_buffer, buf, strlen(buf)); + stderr_bytes += strlen(buf); + quit_pending = 1; + return; + } + } + /* Consume printed data from the buffer. */ + buffer_consume(&stdout_buffer, len); + } + + /* Write buffered output to stderr. */ + if (FD_ISSET(fileno(stderr), writeset)) + { + /* Write as much data as possible. */ + len = write(fileno(stderr), buffer_ptr(&stderr_buffer), + buffer_len(&stderr_buffer)); + if (len <= 0) { + if (errno == EAGAIN) + len = 0; + else + { + /* EOF or error, but can't even print error message. */ + quit_pending = 1; + return; + } + } + /* Consume printed characters from the buffer. */ + buffer_consume(&stderr_buffer, len); + } +} + +/* Implements the interactive session with the server. This is called + after the user has been authenticated, and a command has been + started on the remote host. If escape_char != -1, it is the character + used as an escape character for terminating or suspending the + session. */ + +int client_loop(int have_pty, int escape_char_arg) +{ + double start_time, total_time; + int len; + char buf[100]; + + debug("Entering interactive session."); + + start_time = get_current_time(); + + /* Initialize variables. */ + escape_pending = 0; + last_was_cr = 1; + exit_status = -1; + stdin_eof = 0; + buffer_high = 64 * 1024; + connection_in = packet_get_connection_in(); + connection_out = packet_get_connection_out(); + max_fd = connection_in; + if (connection_out > max_fd) + max_fd = connection_out; + stdin_bytes = 0; + stdout_bytes = 0; + stderr_bytes = 0; + quit_pending = 0; + escape_char = escape_char_arg; + + /* Initialize buffers. */ + buffer_init(&stdin_buffer); + buffer_init(&stdout_buffer); + buffer_init(&stderr_buffer); + + /* Set signal handlers to restore non-blocking mode. */ + signal(SIGINT, signal_handler); + signal(SIGQUIT, signal_handler); + signal(SIGTERM, signal_handler); + signal(SIGPIPE, SIG_IGN); + if (have_pty) + signal(SIGWINCH, window_change_handler); + + /* Enter raw mode if have a pseudo terminal. */ + if (have_pty) + enter_raw_mode(); + + /* Check if we should immediately send of on stdin. */ + client_check_initial_eof_on_stdin(); + + /* Main loop of the client for the interactive session mode. */ + while (!quit_pending) + { + fd_set readset, writeset; + + /* Precess buffered packets sent by the server. */ + client_process_buffered_input_packets(); + + /* Make packets of buffered stdin data, and buffer them for sending + to the server. */ + client_make_packets_from_stdin_data(); + + /* Make packets from buffered channel data, and buffer them for sending + to the server. */ + if (packet_not_very_much_data_to_write()) + channel_output_poll(); + + /* Check if the window size has changed, and buffer a message about + it to the server if so. */ + client_check_window_change(); + + if (quit_pending) + break; + + /* Wait until we have something to do (something becomes available + on one of the descriptors). */ + client_wait_until_can_do_something(&readset, &writeset); + + if (quit_pending) + break; + + /* Do channel operations. */ + channel_after_select(&readset, &writeset); + + /* Process input from the connection and from stdin. Buffer any data + that is available. */ + client_process_input(&readset); + + /* Process output to stdout and stderr. Output to the connection + is processed elsewhere (above). */ + client_process_output(&writeset); + + /* Send as much buffered packet data as possible to the sender. */ + if (FD_ISSET(connection_out, &writeset)) + packet_write_poll(); + } + + /* Terminate the session. */ + + /* Stop watching for window change. */ + if (have_pty) + signal(SIGWINCH, SIG_DFL); + + /* Stop listening for connections. */ + channel_stop_listening(); + + /* In interactive mode (with pseudo tty) display a message indicating that + the connection has been closed. */ + if (have_pty && !quiet_flag) + { + snprintf(buf, sizeof buf, "Connection to %.64s closed.\r\n", host); + buffer_append(&stderr_buffer, buf, strlen(buf)); + stderr_bytes += strlen(buf); + } + + /* Output any buffered data for stdout. */ + while (buffer_len(&stdout_buffer) > 0) + { + len = write(fileno(stdout), buffer_ptr(&stdout_buffer), + buffer_len(&stdout_buffer)); + if (len <= 0) + { + error("Write failed flushing stdout buffer."); + break; + } + buffer_consume(&stdout_buffer, len); + } + + /* Output any buffered data for stderr. */ + while (buffer_len(&stderr_buffer) > 0) + { + len = write(fileno(stderr), buffer_ptr(&stderr_buffer), + buffer_len(&stderr_buffer)); + if (len <= 0) + { + error("Write failed flushing stderr buffer."); + break; + } + buffer_consume(&stderr_buffer, len); + } + + /* Leave raw mode. */ + if (have_pty) + leave_raw_mode(); + + /* Clear and free any buffers. */ + memset(buf, 0, sizeof(buf)); + buffer_free(&stdin_buffer); + buffer_free(&stdout_buffer); + buffer_free(&stderr_buffer); + + /* Report bytes transferred, and transfer rates. */ + total_time = get_current_time() - start_time; + debug("Transferred: stdin %lu, stdout %lu, stderr %lu bytes in %.1f seconds", + stdin_bytes, stdout_bytes, stderr_bytes, total_time); + if (total_time > 0) + debug("Bytes per second: stdin %.1f, stdout %.1f, stderr %.1f", + stdin_bytes / total_time, stdout_bytes / total_time, + stderr_bytes / total_time); + + /* Return the exit status of the program. */ + debug("Exit status %d", exit_status); + return exit_status; +} |