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#include "includes.h"
#include "packet.h"
#include "buffer.h"
#include "session.h"
#include "dbutil.h"
#include "channel.h"
#include "ssh.h"
#include "runopts.h"
#include "termcodes.h"
static void cli_closechansess(struct Channel *channel);
static int cli_initchansess(struct Channel *channel);
static void start_channel_request(struct Channel *channel, unsigned char *type);
static void send_chansess_pty_req(struct Channel *channel);
static void send_chansess_shell_req(struct Channel *channel);
static void cli_tty_setup();
void cli_tty_cleanup();
static const struct ChanType clichansess = {
0, /* sepfds */
"session", /* name */
cli_initchansess, /* inithandler */
NULL, /* checkclosehandler */
NULL, /* reqhandler */
cli_closechansess, /* closehandler */
};
/* If the main session goes, we close it up */
static void cli_closechansess(struct Channel *channel) {
/* This channel hasn't gone yet, so we have > 1 */
if (ses.chancount > 1) {
dropbear_log(LOG_INFO, "Waiting for other channels to close...");
}
cli_tty_cleanup(); /* Restore tty modes etc */
}
static void start_channel_request(struct Channel *channel,
unsigned char *type) {
CHECKCLEARTOWRITE();
buf_putbyte(ses.writepayload, SSH_MSG_CHANNEL_REQUEST);
buf_putint(ses.writepayload, channel->remotechan);
buf_putstring(ses.writepayload, type, strlen(type));
}
/* Taken from OpenSSH's sshtty.c:
* RCSID("OpenBSD: sshtty.c,v 1.5 2003/09/19 17:43:35 markus Exp "); */
static void cli_tty_setup() {
struct termios tio;
TRACE(("enter cli_pty_setup"));
if (cli_ses.tty_raw_mode == 1) {
TRACE(("leave cli_tty_setup: already in raw mode!"));
return;
}
if (tcgetattr(STDIN_FILENO, &tio) == -1) {
dropbear_exit("Failed to set raw TTY mode");
}
/* make a copy */
cli_ses.saved_tio = tio;
tio.c_iflag |= IGNPAR;
tio.c_iflag &= ~(ISTRIP | INLCR | IGNCR | ICRNL | IXON | IXANY | IXOFF);
#ifdef IUCLC
tio.c_iflag &= ~IUCLC;
#endif
tio.c_lflag &= ~(ISIG | ICANON | ECHO | ECHOE | ECHOK | ECHONL);
#ifdef IEXTEN
tio.c_lflag &= ~IEXTEN;
#endif
tio.c_oflag &= ~OPOST;
tio.c_cc[VMIN] = 1;
tio.c_cc[VTIME] = 0;
if (tcsetattr(STDIN_FILENO, TCSADRAIN, &tio) == -1) {
dropbear_exit("Failed to set raw TTY mode");
}
cli_ses.tty_raw_mode = 1;
TRACE(("leave cli_tty_setup"));
}
void cli_tty_cleanup() {
TRACE(("enter cli_tty_cleanup"));
if (cli_ses.tty_raw_mode == 0) {
TRACE(("leave cli_tty_cleanup: not in raw mode"));
return;
}
if (tcsetattr(STDIN_FILENO, TCSADRAIN, &cli_ses.saved_tio) == -1) {
dropbear_log(LOG_WARNING, "Failed restoring TTY");
} else {
cli_ses.tty_raw_mode = 0;
}
TRACE(("leave cli_tty_cleanup"));
}
static void put_termcodes() {
TRACE(("enter put_termcodes"));
struct termios tio;
unsigned int sshcode;
const struct TermCode *termcode;
unsigned int value;
unsigned int mapcode;
unsigned int bufpos1, bufpos2;
if (tcgetattr(STDIN_FILENO, &tio) == -1) {
dropbear_log(LOG_WARNING, "Failed reading termmodes");
buf_putint(ses.writepayload, 1); /* Just the terminator */
buf_putbyte(ses.writepayload, 0); /* TTY_OP_END */
return;
}
bufpos1 = ses.writepayload->pos;
buf_putint(ses.writepayload, 0); /* A placeholder for the final length */
/* As with Dropbear server, we ignore baud rates for now */
for (sshcode = 1; sshcode < MAX_TERMCODE; sshcode++) {
termcode = &termcodes[sshcode];
mapcode = termcode->mapcode;
switch (termcode->type) {
case TERMCODE_NONE:
continue;
case TERMCODE_CONTROLCHAR:
value = tio.c_cc[mapcode];
break;
case TERMCODE_INPUT:
value = tio.c_iflag & mapcode;
break;
case TERMCODE_OUTPUT:
value = tio.c_oflag & mapcode;
break;
case TERMCODE_LOCAL:
value = tio.c_lflag & mapcode;
break;
case TERMCODE_CONTROL:
value = tio.c_cflag & mapcode;
break;
default:
continue;
}
/* If we reach here, we have something to say */
buf_putbyte(ses.writepayload, sshcode);
buf_putint(ses.writepayload, value);
}
buf_putbyte(ses.writepayload, 0); /* THE END, aka TTY_OP_END */
/* Put the string length at the start of the buffer */
bufpos2 = ses.writepayload->pos;
buf_setpos(ses.writepayload, bufpos1); /* Jump back */
buf_putint(ses.writepayload, bufpos2 - bufpos1 - 4); /* len(termcodes) */
buf_setpos(ses.writepayload, bufpos2); /* Back where we were */
TRACE(("leave put_termcodes"));
}
static void put_winsize() {
struct winsize ws;
if (ioctl(STDIN_FILENO, TIOCGWINSZ, &ws) < 0) {
/* Some sane defaults */
ws.ws_row = 25;
ws.ws_col = 80;
ws.ws_xpixel = 0;
ws.ws_ypixel = 0;
}
buf_putint(ses.writepayload, ws.ws_col); /* Cols */
buf_putint(ses.writepayload, ws.ws_row); /* Rows */
buf_putint(ses.writepayload, ws.ws_xpixel); /* Width */
buf_putint(ses.writepayload, ws.ws_ypixel); /* Height */
}
static void sigwinch_handler(int dummy) {
cli_ses.winchange = 1;
}
void cli_chansess_winchange() {
unsigned int i;
struct Channel *channel = NULL;
for (i = 0; i < ses.chansize; i++) {
channel = ses.channels[i];
if (channel != NULL && channel->type == &clichansess) {
CHECKCLEARTOWRITE();
buf_putbyte(ses.writepayload, SSH_MSG_CHANNEL_REQUEST);
buf_putint(ses.writepayload, channel->remotechan);
buf_putstring(ses.writepayload, "window-change", 13);
buf_putbyte(ses.writepayload, 0); /* FALSE says the spec */
put_winsize();
encrypt_packet();
}
}
cli_ses.winchange = 0;
}
static void send_chansess_pty_req(struct Channel *channel) {
unsigned char* term = NULL;
TRACE(("enter send_chansess_pty_req"));
start_channel_request(channel, "pty-req");
/* Don't want replies */
buf_putbyte(ses.writepayload, 0);
/* Get the terminal */
term = getenv("TERM");
if (term == NULL) {
term = "vt100"; /* Seems a safe default */
}
buf_putstring(ses.writepayload, term, strlen(term));
/* Window size */
put_winsize();
/* Terminal mode encoding */
put_termcodes();
encrypt_packet();
/* Set up a window-change handler */
if (signal(SIGWINCH, sigwinch_handler) == SIG_ERR) {
dropbear_exit("signal error");
}
TRACE(("leave send_chansess_pty_req"));
}
static void send_chansess_shell_req(struct Channel *channel) {
unsigned char* reqtype = NULL;
TRACE(("enter send_chansess_shell_req"));
if (cli_opts.cmd) {
reqtype = "exec";
} else {
reqtype = "shell";
}
start_channel_request(channel, reqtype);
/* XXX TODO */
buf_putbyte(ses.writepayload, 0); /* Don't want replies */
if (cli_opts.cmd) {
buf_putstring(ses.writepayload, cli_opts.cmd, strlen(cli_opts.cmd));
}
encrypt_packet();
TRACE(("leave send_chansess_shell_req"));
}
static int cli_initchansess(struct Channel *channel) {
channel->infd = STDOUT_FILENO;
//channel->outfd = STDIN_FILENO;
//channel->errfd = STDERR_FILENO;
if (cli_opts.wantpty) {
send_chansess_pty_req(channel);
}
send_chansess_shell_req(channel);
if (cli_opts.wantpty) {
cli_tty_setup();
}
return 0; /* Success */
}
void cli_send_chansess_request() {
TRACE(("enter cli_send_chansess_request"));
if (send_msg_channel_open_init(STDIN_FILENO, &clichansess)
== DROPBEAR_FAILURE) {
dropbear_exit("Couldn't open initial channel");
}
/* No special channel request data */
encrypt_packet();
TRACE(("leave cli_send_chansess_request"));
}
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