Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 1 | /* |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 2 | * |
| 3 | * clientloop.c |
| 4 | * |
| 5 | * Author: Tatu Ylonen <ylo@cs.hut.fi> |
| 6 | * |
| 7 | * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland |
| 8 | * All rights reserved |
| 9 | * |
| 10 | * |
| 11 | * Created: Sat Sep 23 12:23:57 1995 ylo |
| 12 | * |
| 13 | * The main loop for the interactive session (client side). |
| 14 | * |
| 15 | */ |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 16 | |
| 17 | #include "includes.h" |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 18 | RCSID("$Id: clientloop.c,v 1.6 1999/11/25 00:54:58 damien Exp $"); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 19 | |
| 20 | #include "xmalloc.h" |
| 21 | #include "ssh.h" |
| 22 | #include "packet.h" |
| 23 | #include "buffer.h" |
| 24 | #include "authfd.h" |
Damien Miller | 5ce662a | 1999-11-11 17:57:39 +1100 | [diff] [blame] | 25 | #include "readconf.h" |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 26 | |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 27 | /* Flag indicating that stdin should be redirected from /dev/null. */ |
| 28 | extern int stdin_null_flag; |
| 29 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 30 | /* |
| 31 | * Name of the host we are connecting to. This is the name given on the |
| 32 | * command line, or the HostName specified for the user-supplied name in a |
| 33 | * configuration file. |
| 34 | */ |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 35 | extern char *host; |
| 36 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 37 | /* |
| 38 | * Flag to indicate that we have received a window change signal which has |
| 39 | * not yet been processed. This will cause a message indicating the new |
| 40 | * window size to be sent to the server a little later. This is volatile |
| 41 | * because this is updated in a signal handler. |
| 42 | */ |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 43 | static volatile int received_window_change_signal = 0; |
| 44 | |
| 45 | /* Terminal modes, as saved by enter_raw_mode. */ |
| 46 | static struct termios saved_tio; |
| 47 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 48 | /* |
| 49 | * Flag indicating whether we are in raw mode. This is used by |
| 50 | * enter_raw_mode and leave_raw_mode. |
| 51 | */ |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 52 | static int in_raw_mode = 0; |
| 53 | |
| 54 | /* Flag indicating whether the user\'s terminal is in non-blocking mode. */ |
| 55 | static int in_non_blocking_mode = 0; |
| 56 | |
| 57 | /* Common data for the client loop code. */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 58 | static int escape_pending; /* Last character was the escape character */ |
| 59 | static int last_was_cr; /* Last character was a newline. */ |
| 60 | static int exit_status; /* Used to store the exit status of the command. */ |
| 61 | static int stdin_eof; /* EOF has been encountered on standard error. */ |
| 62 | static Buffer stdin_buffer; /* Buffer for stdin data. */ |
| 63 | static Buffer stdout_buffer; /* Buffer for stdout data. */ |
| 64 | static Buffer stderr_buffer; /* Buffer for stderr data. */ |
| 65 | static unsigned int buffer_high;/* Soft max buffer size. */ |
| 66 | static int max_fd; /* Maximum file descriptor number in select(). */ |
| 67 | static int connection_in; /* Connection to server (input). */ |
| 68 | static int connection_out; /* Connection to server (output). */ |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 69 | static unsigned long stdin_bytes, stdout_bytes, stderr_bytes; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 70 | static int quit_pending; /* Set to non-zero to quit the client loop. */ |
| 71 | static int escape_char; /* Escape character. */ |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 72 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 73 | /* Returns the user\'s terminal to normal mode if it had been put in raw mode. */ |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 74 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 75 | void |
| 76 | leave_raw_mode() |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 77 | { |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 78 | if (!in_raw_mode) |
| 79 | return; |
| 80 | in_raw_mode = 0; |
| 81 | if (tcsetattr(fileno(stdin), TCSADRAIN, &saved_tio) < 0) |
| 82 | perror("tcsetattr"); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 83 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 84 | fatal_remove_cleanup((void (*) (void *)) leave_raw_mode, NULL); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 85 | } |
| 86 | |
| 87 | /* Puts the user\'s terminal in raw mode. */ |
| 88 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 89 | void |
| 90 | enter_raw_mode() |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 91 | { |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 92 | struct termios tio; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 93 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 94 | if (tcgetattr(fileno(stdin), &tio) < 0) |
| 95 | perror("tcgetattr"); |
| 96 | saved_tio = tio; |
| 97 | tio.c_iflag |= IGNPAR; |
| 98 | tio.c_iflag &= ~(ISTRIP | INLCR | IGNCR | ICRNL | IXON | IXANY | IXOFF); |
| 99 | tio.c_lflag &= ~(ISIG | ICANON | ECHO | ECHOE | ECHOK | ECHONL); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 100 | #ifdef IEXTEN |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 101 | tio.c_lflag &= ~IEXTEN; |
| 102 | #endif /* IEXTEN */ |
| 103 | tio.c_oflag &= ~OPOST; |
| 104 | tio.c_cc[VMIN] = 1; |
| 105 | tio.c_cc[VTIME] = 0; |
| 106 | if (tcsetattr(fileno(stdin), TCSADRAIN, &tio) < 0) |
| 107 | perror("tcsetattr"); |
| 108 | in_raw_mode = 1; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 109 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 110 | fatal_add_cleanup((void (*) (void *)) leave_raw_mode, NULL); |
| 111 | } |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 112 | |
| 113 | /* Restores stdin to blocking mode. */ |
| 114 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 115 | void |
| 116 | leave_non_blocking() |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 117 | { |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 118 | if (in_non_blocking_mode) { |
| 119 | (void) fcntl(fileno(stdin), F_SETFL, 0); |
| 120 | in_non_blocking_mode = 0; |
| 121 | fatal_remove_cleanup((void (*) (void *)) leave_non_blocking, NULL); |
| 122 | } |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 123 | } |
| 124 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 125 | /* Puts stdin terminal in non-blocking mode. */ |
| 126 | |
| 127 | void |
| 128 | enter_non_blocking() |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 129 | { |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 130 | in_non_blocking_mode = 1; |
| 131 | (void) fcntl(fileno(stdin), F_SETFL, O_NONBLOCK); |
| 132 | fatal_add_cleanup((void (*) (void *)) leave_non_blocking, NULL); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 133 | } |
| 134 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 135 | /* |
| 136 | * Signal handler for the window change signal (SIGWINCH). This just sets a |
| 137 | * flag indicating that the window has changed. |
| 138 | */ |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 139 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 140 | void |
| 141 | window_change_handler(int sig) |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 142 | { |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 143 | received_window_change_signal = 1; |
| 144 | signal(SIGWINCH, window_change_handler); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 145 | } |
| 146 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 147 | /* |
| 148 | * Signal handler for signals that cause the program to terminate. These |
| 149 | * signals must be trapped to restore terminal modes. |
| 150 | */ |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 151 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 152 | void |
| 153 | signal_handler(int sig) |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 154 | { |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 155 | if (in_raw_mode) |
| 156 | leave_raw_mode(); |
| 157 | if (in_non_blocking_mode) |
| 158 | leave_non_blocking(); |
| 159 | channel_stop_listening(); |
| 160 | packet_close(); |
| 161 | fatal("Killed by signal %d.", sig); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 162 | } |
| 163 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 164 | /* |
| 165 | * Returns current time in seconds from Jan 1, 1970 with the maximum |
| 166 | * available resolution. |
| 167 | */ |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 168 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 169 | double |
| 170 | get_current_time() |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 171 | { |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 172 | struct timeval tv; |
| 173 | gettimeofday(&tv, NULL); |
| 174 | return (double) tv.tv_sec + (double) tv.tv_usec / 1000000.0; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 175 | } |
| 176 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 177 | /* |
| 178 | * This is called when the interactive is entered. This checks if there is |
| 179 | * an EOF coming on stdin. We must check this explicitly, as select() does |
| 180 | * not appear to wake up when redirecting from /dev/null. |
| 181 | */ |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 182 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 183 | void |
| 184 | client_check_initial_eof_on_stdin() |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 185 | { |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 186 | int len; |
| 187 | char buf[1]; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 188 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 189 | /* |
| 190 | * If standard input is to be "redirected from /dev/null", we simply |
| 191 | * mark that we have seen an EOF and send an EOF message to the |
| 192 | * server. Otherwise, we try to read a single character; it appears |
| 193 | * that for some files, such /dev/null, select() never wakes up for |
| 194 | * read for this descriptor, which means that we never get EOF. This |
| 195 | * way we will get the EOF if stdin comes from /dev/null or similar. |
| 196 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 197 | if (stdin_null_flag) { |
| 198 | /* Fake EOF on stdin. */ |
| 199 | debug("Sending eof."); |
| 200 | stdin_eof = 1; |
| 201 | packet_start(SSH_CMSG_EOF); |
| 202 | packet_send(); |
| 203 | } else { |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 204 | enter_non_blocking(); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 205 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 206 | /* Check for immediate EOF on stdin. */ |
| 207 | len = read(fileno(stdin), buf, 1); |
| 208 | if (len == 0) { |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 209 | /* EOF. Record that we have seen it and send EOF to server. */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 210 | debug("Sending eof."); |
| 211 | stdin_eof = 1; |
| 212 | packet_start(SSH_CMSG_EOF); |
| 213 | packet_send(); |
| 214 | } else if (len > 0) { |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 215 | /* |
| 216 | * Got data. We must store the data in the buffer, |
| 217 | * and also process it as an escape character if |
| 218 | * appropriate. |
| 219 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 220 | if ((unsigned char) buf[0] == escape_char) |
| 221 | escape_pending = 1; |
| 222 | else { |
| 223 | buffer_append(&stdin_buffer, buf, 1); |
| 224 | stdin_bytes += 1; |
| 225 | } |
| 226 | } |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 227 | leave_non_blocking(); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 228 | } |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 229 | } |
| 230 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 231 | /* |
| 232 | * Get packets from the connection input buffer, and process them as long as |
| 233 | * there are packets available. |
| 234 | */ |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 235 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 236 | void |
| 237 | client_process_buffered_input_packets() |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 238 | { |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 239 | int type; |
| 240 | char *data; |
| 241 | unsigned int data_len; |
| 242 | int payload_len; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 243 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 244 | /* Process any buffered packets from the server. */ |
| 245 | while (!quit_pending && |
| 246 | (type = packet_read_poll(&payload_len)) != SSH_MSG_NONE) { |
| 247 | switch (type) { |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 248 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 249 | case SSH_SMSG_STDOUT_DATA: |
| 250 | data = packet_get_string(&data_len); |
| 251 | packet_integrity_check(payload_len, 4 + data_len, type); |
| 252 | buffer_append(&stdout_buffer, data, data_len); |
| 253 | stdout_bytes += data_len; |
| 254 | memset(data, 0, data_len); |
| 255 | xfree(data); |
| 256 | break; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 257 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 258 | case SSH_SMSG_STDERR_DATA: |
| 259 | data = packet_get_string(&data_len); |
| 260 | packet_integrity_check(payload_len, 4 + data_len, type); |
| 261 | buffer_append(&stderr_buffer, data, data_len); |
| 262 | stdout_bytes += data_len; |
| 263 | memset(data, 0, data_len); |
| 264 | xfree(data); |
| 265 | break; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 266 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 267 | case SSH_SMSG_EXITSTATUS: |
| 268 | packet_integrity_check(payload_len, 4, type); |
| 269 | exit_status = packet_get_int(); |
| 270 | /* Acknowledge the exit. */ |
| 271 | packet_start(SSH_CMSG_EXIT_CONFIRMATION); |
| 272 | packet_send(); |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 273 | /* |
| 274 | * Must wait for packet to be sent since we are |
| 275 | * exiting the loop. |
| 276 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 277 | packet_write_wait(); |
| 278 | /* Flag that we want to exit. */ |
| 279 | quit_pending = 1; |
| 280 | break; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 281 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 282 | case SSH_SMSG_X11_OPEN: |
| 283 | x11_input_open(payload_len); |
| 284 | break; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 285 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 286 | case SSH_MSG_PORT_OPEN: |
| 287 | channel_input_port_open(payload_len); |
| 288 | break; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 289 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 290 | case SSH_SMSG_AGENT_OPEN: |
| 291 | packet_integrity_check(payload_len, 4, type); |
| 292 | auth_input_open_request(); |
| 293 | break; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 294 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 295 | case SSH_MSG_CHANNEL_OPEN_CONFIRMATION: |
| 296 | packet_integrity_check(payload_len, 4 + 4, type); |
| 297 | channel_input_open_confirmation(); |
| 298 | break; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 299 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 300 | case SSH_MSG_CHANNEL_OPEN_FAILURE: |
| 301 | packet_integrity_check(payload_len, 4, type); |
| 302 | channel_input_open_failure(); |
| 303 | break; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 304 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 305 | case SSH_MSG_CHANNEL_DATA: |
| 306 | channel_input_data(payload_len); |
| 307 | break; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 308 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 309 | case SSH_MSG_CHANNEL_CLOSE: |
| 310 | packet_integrity_check(payload_len, 4, type); |
| 311 | channel_input_close(); |
| 312 | break; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 313 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 314 | case SSH_MSG_CHANNEL_CLOSE_CONFIRMATION: |
| 315 | packet_integrity_check(payload_len, 4, type); |
| 316 | channel_input_close_confirmation(); |
| 317 | break; |
| 318 | |
| 319 | default: |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 320 | /* |
| 321 | * Any unknown packets received during the actual |
| 322 | * session cause the session to terminate. This is |
| 323 | * intended to make debugging easier since no |
| 324 | * confirmations are sent. Any compatible protocol |
| 325 | * extensions must be negotiated during the |
| 326 | * preparatory phase. |
| 327 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 328 | packet_disconnect("Protocol error during session: type %d", |
| 329 | type); |
| 330 | } |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 331 | } |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 332 | } |
| 333 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 334 | /* |
| 335 | * Make packets from buffered stdin data, and buffer them for sending to the |
| 336 | * connection. |
| 337 | */ |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 338 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 339 | void |
| 340 | client_make_packets_from_stdin_data() |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 341 | { |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 342 | unsigned int len; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 343 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 344 | /* Send buffered stdin data to the server. */ |
| 345 | while (buffer_len(&stdin_buffer) > 0 && |
| 346 | packet_not_very_much_data_to_write()) { |
| 347 | len = buffer_len(&stdin_buffer); |
| 348 | /* Keep the packets at reasonable size. */ |
| 349 | if (len > packet_get_maxsize()) |
| 350 | len = packet_get_maxsize(); |
| 351 | packet_start(SSH_CMSG_STDIN_DATA); |
| 352 | packet_put_string(buffer_ptr(&stdin_buffer), len); |
| 353 | packet_send(); |
| 354 | buffer_consume(&stdin_buffer, len); |
| 355 | /* If we have a pending EOF, send it now. */ |
| 356 | if (stdin_eof && buffer_len(&stdin_buffer) == 0) { |
| 357 | packet_start(SSH_CMSG_EOF); |
| 358 | packet_send(); |
| 359 | } |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 360 | } |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 361 | } |
| 362 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 363 | /* |
| 364 | * Checks if the client window has changed, and sends a packet about it to |
| 365 | * the server if so. The actual change is detected elsewhere (by a software |
| 366 | * interrupt on Unix); this just checks the flag and sends a message if |
| 367 | * appropriate. |
| 368 | */ |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 369 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 370 | void |
| 371 | client_check_window_change() |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 372 | { |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 373 | /* Send possible window change message to the server. */ |
| 374 | if (received_window_change_signal) { |
| 375 | struct winsize ws; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 376 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 377 | /* Clear the window change indicator. */ |
| 378 | received_window_change_signal = 0; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 379 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 380 | /* Read new window size. */ |
| 381 | if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) >= 0) { |
| 382 | /* Successful, send the packet now. */ |
| 383 | packet_start(SSH_CMSG_WINDOW_SIZE); |
| 384 | packet_put_int(ws.ws_row); |
| 385 | packet_put_int(ws.ws_col); |
| 386 | packet_put_int(ws.ws_xpixel); |
| 387 | packet_put_int(ws.ws_ypixel); |
| 388 | packet_send(); |
| 389 | } |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 390 | } |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 391 | } |
| 392 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 393 | /* |
| 394 | * Waits until the client can do something (some data becomes available on |
| 395 | * one of the file descriptors). |
| 396 | */ |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 397 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 398 | void |
| 399 | client_wait_until_can_do_something(fd_set * readset, fd_set * writeset) |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 400 | { |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 401 | /* Initialize select masks. */ |
| 402 | FD_ZERO(readset); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 403 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 404 | /* Read from the connection, unless our buffers are full. */ |
| 405 | if (buffer_len(&stdout_buffer) < buffer_high && |
| 406 | buffer_len(&stderr_buffer) < buffer_high && |
| 407 | channel_not_very_much_buffered_data()) |
| 408 | FD_SET(connection_in, readset); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 409 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 410 | /* |
| 411 | * Read from stdin, unless we have seen EOF or have very much |
| 412 | * buffered data to send to the server. |
| 413 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 414 | if (!stdin_eof && packet_not_very_much_data_to_write()) |
| 415 | FD_SET(fileno(stdin), readset); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 416 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 417 | FD_ZERO(writeset); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 418 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 419 | /* Add any selections by the channel mechanism. */ |
| 420 | channel_prepare_select(readset, writeset); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 421 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 422 | /* Select server connection if have data to write to the server. */ |
| 423 | if (packet_have_data_to_write()) |
| 424 | FD_SET(connection_out, writeset); |
| 425 | |
| 426 | /* Select stdout if have data in buffer. */ |
| 427 | if (buffer_len(&stdout_buffer) > 0) |
| 428 | FD_SET(fileno(stdout), writeset); |
| 429 | |
| 430 | /* Select stderr if have data in buffer. */ |
| 431 | if (buffer_len(&stderr_buffer) > 0) |
| 432 | FD_SET(fileno(stderr), writeset); |
| 433 | |
| 434 | /* Update maximum file descriptor number, if appropriate. */ |
| 435 | if (channel_max_fd() > max_fd) |
| 436 | max_fd = channel_max_fd(); |
| 437 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 438 | /* |
| 439 | * Wait for something to happen. This will suspend the process until |
| 440 | * some selected descriptor can be read, written, or has some other |
| 441 | * event pending. Note: if you want to implement SSH_MSG_IGNORE |
| 442 | * messages to fool traffic analysis, this might be the place to do |
| 443 | * it: just have a random timeout for the select, and send a random |
| 444 | * SSH_MSG_IGNORE packet when the timeout expires. |
| 445 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 446 | |
| 447 | if (select(max_fd + 1, readset, writeset, NULL, NULL) < 0) { |
| 448 | char buf[100]; |
| 449 | /* Some systems fail to clear these automatically. */ |
| 450 | FD_ZERO(readset); |
| 451 | FD_ZERO(writeset); |
| 452 | if (errno == EINTR) |
| 453 | return; |
| 454 | /* Note: we might still have data in the buffers. */ |
| 455 | snprintf(buf, sizeof buf, "select: %s\r\n", strerror(errno)); |
| 456 | buffer_append(&stderr_buffer, buf, strlen(buf)); |
| 457 | stderr_bytes += strlen(buf); |
| 458 | quit_pending = 1; |
| 459 | } |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 460 | } |
| 461 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 462 | void |
| 463 | client_suspend_self() |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 464 | { |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 465 | struct winsize oldws, newws; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 466 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 467 | /* Flush stdout and stderr buffers. */ |
| 468 | if (buffer_len(&stdout_buffer) > 0) |
| 469 | write(fileno(stdout), |
| 470 | buffer_ptr(&stdout_buffer), |
| 471 | buffer_len(&stdout_buffer)); |
| 472 | if (buffer_len(&stderr_buffer) > 0) |
| 473 | write(fileno(stderr), |
| 474 | buffer_ptr(&stderr_buffer), |
| 475 | buffer_len(&stderr_buffer)); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 476 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 477 | leave_raw_mode(); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 478 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 479 | /* |
| 480 | * Free (and clear) the buffer to reduce the amount of data that gets |
| 481 | * written to swap. |
| 482 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 483 | buffer_free(&stdin_buffer); |
| 484 | buffer_free(&stdout_buffer); |
| 485 | buffer_free(&stderr_buffer); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 486 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 487 | /* Save old window size. */ |
| 488 | ioctl(fileno(stdin), TIOCGWINSZ, &oldws); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 489 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 490 | /* Send the suspend signal to the program itself. */ |
| 491 | kill(getpid(), SIGTSTP); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 492 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 493 | /* Check if the window size has changed. */ |
| 494 | if (ioctl(fileno(stdin), TIOCGWINSZ, &newws) >= 0 && |
| 495 | (oldws.ws_row != newws.ws_row || |
| 496 | oldws.ws_col != newws.ws_col || |
| 497 | oldws.ws_xpixel != newws.ws_xpixel || |
| 498 | oldws.ws_ypixel != newws.ws_ypixel)) |
| 499 | received_window_change_signal = 1; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 500 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 501 | /* OK, we have been continued by the user. Reinitialize buffers. */ |
| 502 | buffer_init(&stdin_buffer); |
| 503 | buffer_init(&stdout_buffer); |
| 504 | buffer_init(&stderr_buffer); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 505 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 506 | enter_raw_mode(); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 507 | } |
| 508 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 509 | void |
| 510 | client_process_input(fd_set * readset) |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 511 | { |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 512 | int len, pid; |
| 513 | char buf[8192], *s; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 514 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 515 | /* |
| 516 | * Read input from the server, and add any such data to the buffer of |
| 517 | * the packet subsystem. |
| 518 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 519 | if (FD_ISSET(connection_in, readset)) { |
| 520 | /* Read as much as possible. */ |
| 521 | len = read(connection_in, buf, sizeof(buf)); |
| 522 | if (len == 0) { |
| 523 | /* Received EOF. The remote host has closed the connection. */ |
| 524 | snprintf(buf, sizeof buf, "Connection to %.300s closed by remote host.\r\n", |
| 525 | host); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 526 | buffer_append(&stderr_buffer, buf, strlen(buf)); |
| 527 | stderr_bytes += strlen(buf); |
| 528 | quit_pending = 1; |
| 529 | return; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 530 | } |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 531 | /* |
| 532 | * There is a kernel bug on Solaris that causes select to |
| 533 | * sometimes wake up even though there is no data available. |
| 534 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 535 | if (len < 0 && errno == EAGAIN) |
| 536 | len = 0; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 537 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 538 | if (len < 0) { |
| 539 | /* An error has encountered. Perhaps there is a network problem. */ |
| 540 | snprintf(buf, sizeof buf, "Read from remote host %.300s: %.100s\r\n", |
| 541 | host, strerror(errno)); |
| 542 | buffer_append(&stderr_buffer, buf, strlen(buf)); |
| 543 | stderr_bytes += strlen(buf); |
| 544 | quit_pending = 1; |
| 545 | return; |
| 546 | } |
| 547 | packet_process_incoming(buf, len); |
| 548 | } |
| 549 | /* Read input from stdin. */ |
| 550 | if (FD_ISSET(fileno(stdin), readset)) { |
| 551 | /* Read as much as possible. */ |
| 552 | len = read(fileno(stdin), buf, sizeof(buf)); |
| 553 | if (len <= 0) { |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 554 | /* |
| 555 | * Received EOF or error. They are treated |
| 556 | * similarly, except that an error message is printed |
| 557 | * if it was an error condition. |
| 558 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 559 | if (len < 0) { |
| 560 | snprintf(buf, sizeof buf, "read: %.100s\r\n", strerror(errno)); |
| 561 | buffer_append(&stderr_buffer, buf, strlen(buf)); |
| 562 | stderr_bytes += strlen(buf); |
| 563 | } |
| 564 | /* Mark that we have seen EOF. */ |
| 565 | stdin_eof = 1; |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 566 | /* |
| 567 | * Send an EOF message to the server unless there is |
| 568 | * data in the buffer. If there is data in the |
| 569 | * buffer, no message will be sent now. Code |
| 570 | * elsewhere will send the EOF when the buffer |
| 571 | * becomes empty if stdin_eof is set. |
| 572 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 573 | if (buffer_len(&stdin_buffer) == 0) { |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 574 | packet_start(SSH_CMSG_EOF); |
| 575 | packet_send(); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 576 | } |
| 577 | } else if (escape_char == -1) { |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 578 | /* |
| 579 | * Normal successful read, and no escape character. |
| 580 | * Just append the data to buffer. |
| 581 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 582 | buffer_append(&stdin_buffer, buf, len); |
| 583 | stdin_bytes += len; |
| 584 | } else { |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 585 | /* |
| 586 | * Normal, successful read. But we have an escape character |
| 587 | * and have to process the characters one by one. |
| 588 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 589 | unsigned int i; |
| 590 | for (i = 0; i < len; i++) { |
| 591 | unsigned char ch; |
| 592 | /* Get one character at a time. */ |
| 593 | ch = buf[i]; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 594 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 595 | if (escape_pending) { |
| 596 | /* We have previously seen an escape character. */ |
| 597 | /* Clear the flag now. */ |
| 598 | escape_pending = 0; |
| 599 | /* Process the escaped character. */ |
| 600 | switch (ch) { |
| 601 | case '.': |
| 602 | /* Terminate the connection. */ |
| 603 | snprintf(buf, sizeof buf, "%c.\r\n", escape_char); |
| 604 | buffer_append(&stderr_buffer, buf, strlen(buf)); |
| 605 | stderr_bytes += strlen(buf); |
| 606 | quit_pending = 1; |
| 607 | return; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 608 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 609 | case 'Z' - 64: |
| 610 | /* Suspend the program. */ |
| 611 | /* Print a message to that effect to the user. */ |
| 612 | snprintf(buf, sizeof buf, "%c^Z\r\n", escape_char); |
| 613 | buffer_append(&stderr_buffer, buf, strlen(buf)); |
| 614 | stderr_bytes += strlen(buf); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 615 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 616 | /* Restore terminal modes and suspend. */ |
| 617 | client_suspend_self(); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 618 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 619 | /* We have been continued. */ |
| 620 | continue; |
| 621 | |
| 622 | case '&': |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 623 | /* |
| 624 | * Detach the program (continue to serve connections, |
| 625 | * but put in background and no more new connections). |
| 626 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 627 | if (!stdin_eof) { |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 628 | /* |
| 629 | * Sending SSH_CMSG_EOF alone does not always appear |
| 630 | * to be enough. So we try to send an EOF character |
| 631 | * first. |
| 632 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 633 | packet_start(SSH_CMSG_STDIN_DATA); |
| 634 | packet_put_string("\004", 1); |
| 635 | packet_send(); |
| 636 | /* Close stdin. */ |
| 637 | stdin_eof = 1; |
| 638 | if (buffer_len(&stdin_buffer) == 0) { |
| 639 | packet_start(SSH_CMSG_EOF); |
| 640 | packet_send(); |
| 641 | } |
| 642 | } |
| 643 | /* Restore tty modes. */ |
| 644 | leave_raw_mode(); |
| 645 | |
| 646 | /* Stop listening for new connections. */ |
| 647 | channel_stop_listening(); |
| 648 | |
| 649 | printf("%c& [backgrounded]\n", escape_char); |
| 650 | |
| 651 | /* Fork into background. */ |
| 652 | pid = fork(); |
| 653 | if (pid < 0) { |
| 654 | error("fork: %.100s", strerror(errno)); |
| 655 | continue; |
| 656 | } |
| 657 | if (pid != 0) { /* This is the parent. */ |
| 658 | /* The parent just exits. */ |
| 659 | exit(0); |
| 660 | } |
| 661 | /* The child continues serving connections. */ |
| 662 | continue; |
| 663 | |
| 664 | case '?': |
| 665 | snprintf(buf, sizeof buf, |
| 666 | "%c?\r\n\ |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 667 | Supported escape sequences:\r\n\ |
| 668 | ~. - terminate connection\r\n\ |
| 669 | ~^Z - suspend ssh\r\n\ |
| 670 | ~# - list forwarded connections\r\n\ |
| 671 | ~& - background ssh (when waiting for connections to terminate)\r\n\ |
| 672 | ~? - this message\r\n\ |
| 673 | ~~ - send the escape character by typing it twice\r\n\ |
| 674 | (Note that escapes are only recognized immediately after newline.)\r\n", |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 675 | escape_char); |
| 676 | buffer_append(&stderr_buffer, buf, strlen(buf)); |
| 677 | continue; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 678 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 679 | case '#': |
| 680 | snprintf(buf, sizeof buf, "%c#\r\n", escape_char); |
| 681 | buffer_append(&stderr_buffer, buf, strlen(buf)); |
| 682 | s = channel_open_message(); |
| 683 | buffer_append(&stderr_buffer, s, strlen(s)); |
| 684 | xfree(s); |
| 685 | continue; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 686 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 687 | default: |
| 688 | if (ch != escape_char) { |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 689 | /* |
| 690 | * Escape character followed by non-special character. |
| 691 | * Append both to the input buffer. |
| 692 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 693 | buf[0] = escape_char; |
| 694 | buf[1] = ch; |
| 695 | buffer_append(&stdin_buffer, buf, 2); |
| 696 | stdin_bytes += 2; |
| 697 | continue; |
| 698 | } |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 699 | /* |
| 700 | * Note that escape character typed twice |
| 701 | * falls through here; the latter gets processed |
| 702 | * as a normal character below. |
| 703 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 704 | break; |
| 705 | } |
| 706 | } else { |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 707 | /* |
| 708 | * The previous character was not an escape char. Check if this |
| 709 | * is an escape. |
| 710 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 711 | if (last_was_cr && ch == escape_char) { |
| 712 | /* It is. Set the flag and continue to next character. */ |
| 713 | escape_pending = 1; |
| 714 | continue; |
| 715 | } |
| 716 | } |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 717 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 718 | /* |
| 719 | * Normal character. Record whether it was a newline, |
| 720 | * and append it to the buffer. |
| 721 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 722 | last_was_cr = (ch == '\r' || ch == '\n'); |
| 723 | buf[0] = ch; |
| 724 | buffer_append(&stdin_buffer, buf, 1); |
| 725 | stdin_bytes += 1; |
| 726 | continue; |
| 727 | } |
| 728 | } |
| 729 | } |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 730 | } |
| 731 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 732 | void |
| 733 | client_process_output(fd_set * writeset) |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 734 | { |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 735 | int len; |
| 736 | char buf[100]; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 737 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 738 | /* Write buffered output to stdout. */ |
| 739 | if (FD_ISSET(fileno(stdout), writeset)) { |
| 740 | /* Write as much data as possible. */ |
| 741 | len = write(fileno(stdout), buffer_ptr(&stdout_buffer), |
| 742 | buffer_len(&stdout_buffer)); |
| 743 | if (len <= 0) { |
| 744 | if (errno == EAGAIN) |
| 745 | len = 0; |
| 746 | else { |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 747 | /* |
| 748 | * An error or EOF was encountered. Put an |
| 749 | * error message to stderr buffer. |
| 750 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 751 | snprintf(buf, sizeof buf, "write stdout: %.50s\r\n", strerror(errno)); |
| 752 | buffer_append(&stderr_buffer, buf, strlen(buf)); |
| 753 | stderr_bytes += strlen(buf); |
| 754 | quit_pending = 1; |
| 755 | return; |
| 756 | } |
| 757 | } |
| 758 | /* Consume printed data from the buffer. */ |
| 759 | buffer_consume(&stdout_buffer, len); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 760 | } |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 761 | /* Write buffered output to stderr. */ |
| 762 | if (FD_ISSET(fileno(stderr), writeset)) { |
| 763 | /* Write as much data as possible. */ |
| 764 | len = write(fileno(stderr), buffer_ptr(&stderr_buffer), |
| 765 | buffer_len(&stderr_buffer)); |
| 766 | if (len <= 0) { |
| 767 | if (errno == EAGAIN) |
| 768 | len = 0; |
| 769 | else { |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 770 | /* EOF or error, but can't even print error message. */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 771 | quit_pending = 1; |
| 772 | return; |
| 773 | } |
| 774 | } |
| 775 | /* Consume printed characters from the buffer. */ |
| 776 | buffer_consume(&stderr_buffer, len); |
| 777 | } |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 778 | } |
| 779 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 780 | /* |
| 781 | * Implements the interactive session with the server. This is called after |
| 782 | * the user has been authenticated, and a command has been started on the |
| 783 | * remote host. If escape_char != -1, it is the character used as an escape |
| 784 | * character for terminating or suspending the session. |
| 785 | */ |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 786 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 787 | int |
| 788 | client_loop(int have_pty, int escape_char_arg) |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 789 | { |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 790 | extern Options options; |
| 791 | double start_time, total_time; |
| 792 | int len; |
| 793 | char buf[100]; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 794 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 795 | debug("Entering interactive session."); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 796 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 797 | start_time = get_current_time(); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 798 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 799 | /* Initialize variables. */ |
| 800 | escape_pending = 0; |
| 801 | last_was_cr = 1; |
| 802 | exit_status = -1; |
| 803 | stdin_eof = 0; |
| 804 | buffer_high = 64 * 1024; |
| 805 | connection_in = packet_get_connection_in(); |
| 806 | connection_out = packet_get_connection_out(); |
| 807 | max_fd = connection_in; |
| 808 | if (connection_out > max_fd) |
| 809 | max_fd = connection_out; |
| 810 | stdin_bytes = 0; |
| 811 | stdout_bytes = 0; |
| 812 | stderr_bytes = 0; |
| 813 | quit_pending = 0; |
| 814 | escape_char = escape_char_arg; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 815 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 816 | /* Initialize buffers. */ |
| 817 | buffer_init(&stdin_buffer); |
| 818 | buffer_init(&stdout_buffer); |
| 819 | buffer_init(&stderr_buffer); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 820 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 821 | /* Set signal handlers to restore non-blocking mode. */ |
| 822 | signal(SIGINT, signal_handler); |
| 823 | signal(SIGQUIT, signal_handler); |
| 824 | signal(SIGTERM, signal_handler); |
| 825 | signal(SIGPIPE, SIG_IGN); |
| 826 | if (have_pty) |
| 827 | signal(SIGWINCH, window_change_handler); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 828 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 829 | if (have_pty) |
| 830 | enter_raw_mode(); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 831 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 832 | /* Check if we should immediately send of on stdin. */ |
| 833 | client_check_initial_eof_on_stdin(); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 834 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 835 | /* Main loop of the client for the interactive session mode. */ |
| 836 | while (!quit_pending) { |
| 837 | fd_set readset, writeset; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 838 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 839 | /* Process buffered packets sent by the server. */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 840 | client_process_buffered_input_packets(); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 841 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 842 | /* |
| 843 | * Make packets of buffered stdin data, and buffer them for |
| 844 | * sending to the server. |
| 845 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 846 | client_make_packets_from_stdin_data(); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 847 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 848 | /* |
| 849 | * Make packets from buffered channel data, and buffer them |
| 850 | * for sending to the server. |
| 851 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 852 | if (packet_not_very_much_data_to_write()) |
| 853 | channel_output_poll(); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 854 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 855 | /* |
| 856 | * Check if the window size has changed, and buffer a message |
| 857 | * about it to the server if so. |
| 858 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 859 | client_check_window_change(); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 860 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 861 | if (quit_pending) |
| 862 | break; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 863 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 864 | /* |
| 865 | * Wait until we have something to do (something becomes |
| 866 | * available on one of the descriptors). |
| 867 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 868 | client_wait_until_can_do_something(&readset, &writeset); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 869 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 870 | if (quit_pending) |
| 871 | break; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 872 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 873 | /* Do channel operations. */ |
| 874 | channel_after_select(&readset, &writeset); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 875 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 876 | /* |
| 877 | * Process input from the connection and from stdin. Buffer |
| 878 | * any data that is available. |
| 879 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 880 | client_process_input(&readset); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 881 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 882 | /* |
| 883 | * Process output to stdout and stderr. Output to the |
| 884 | * connection is processed elsewhere (above). |
| 885 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 886 | client_process_output(&writeset); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 887 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 888 | /* Send as much buffered packet data as possible to the sender. */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 889 | if (FD_ISSET(connection_out, &writeset)) |
| 890 | packet_write_poll(); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 891 | } |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 892 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 893 | /* Terminate the session. */ |
| 894 | |
| 895 | /* Stop watching for window change. */ |
| 896 | if (have_pty) |
| 897 | signal(SIGWINCH, SIG_DFL); |
| 898 | |
| 899 | /* Stop listening for connections. */ |
| 900 | channel_stop_listening(); |
| 901 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 902 | /* |
| 903 | * In interactive mode (with pseudo tty) display a message indicating |
| 904 | * that the connection has been closed. |
| 905 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 906 | if (have_pty && options.log_level != SYSLOG_LEVEL_QUIET) { |
| 907 | snprintf(buf, sizeof buf, "Connection to %.64s closed.\r\n", host); |
| 908 | buffer_append(&stderr_buffer, buf, strlen(buf)); |
| 909 | stderr_bytes += strlen(buf); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 910 | } |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 911 | /* Output any buffered data for stdout. */ |
| 912 | while (buffer_len(&stdout_buffer) > 0) { |
| 913 | len = write(fileno(stdout), buffer_ptr(&stdout_buffer), |
| 914 | buffer_len(&stdout_buffer)); |
| 915 | if (len <= 0) { |
| 916 | error("Write failed flushing stdout buffer."); |
| 917 | break; |
| 918 | } |
| 919 | buffer_consume(&stdout_buffer, len); |
| 920 | } |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 921 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 922 | /* Output any buffered data for stderr. */ |
| 923 | while (buffer_len(&stderr_buffer) > 0) { |
| 924 | len = write(fileno(stderr), buffer_ptr(&stderr_buffer), |
| 925 | buffer_len(&stderr_buffer)); |
| 926 | if (len <= 0) { |
| 927 | error("Write failed flushing stderr buffer."); |
| 928 | break; |
| 929 | } |
| 930 | buffer_consume(&stderr_buffer, len); |
| 931 | } |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 932 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 933 | if (have_pty) |
| 934 | leave_raw_mode(); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 935 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 936 | /* Clear and free any buffers. */ |
| 937 | memset(buf, 0, sizeof(buf)); |
| 938 | buffer_free(&stdin_buffer); |
| 939 | buffer_free(&stdout_buffer); |
| 940 | buffer_free(&stderr_buffer); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 941 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 942 | /* Report bytes transferred, and transfer rates. */ |
| 943 | total_time = get_current_time() - start_time; |
| 944 | debug("Transferred: stdin %lu, stdout %lu, stderr %lu bytes in %.1f seconds", |
| 945 | stdin_bytes, stdout_bytes, stderr_bytes, total_time); |
| 946 | if (total_time > 0) |
| 947 | debug("Bytes per second: stdin %.1f, stdout %.1f, stderr %.1f", |
| 948 | stdin_bytes / total_time, stdout_bytes / total_time, |
| 949 | stderr_bytes / total_time); |
| 950 | |
| 951 | /* Return the exit status of the program. */ |
| 952 | debug("Exit status %d", exit_status); |
| 953 | return exit_status; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 954 | } |