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/* Glue to tie telnet.c from ttywatch to the loader */
#include <arpa/inet.h>
#include <errno.h>
#include <netinet/in.h>
#include <pty.h>
#include <string.h>
#include <sys/poll.h>
#include <sys/signal.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <termios.h>
#include <unistd.h>
#include "log.h"
#include "telnet.h"
/* Forks, keeping the loader as our child (so we know when it dies). */
int beTelnet(void) {
int sock;
int conn;
int addrLength;
pid_t child;
int i;
int masterFd;
struct sockaddr_in address;
char buf[4096];
struct pollfd fds[3];
telnet_state ts = TS_DATA;
struct termios orig, new;
if ((sock = socket(PF_INET, SOCK_STREAM, 0)) < 0) {
logMessage("socket: %s", strerror(errno));
return -1;
}
address.sin_family = AF_INET;
address.sin_port = htons(IPPORT_TELNET);
memset(&address.sin_addr, 0, sizeof(address.sin_addr));
addrLength = sizeof(address);
/* Let the kernel reuse the socket address. This lets us run
twice in a row, without waiting for the (ip, port) tuple
to time out. Makes testing much easier*/
conn = 1;
setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &conn, sizeof(conn));
bind(sock, (struct sockaddr *) &address, sizeof(address));
listen(sock, 5);
printf("Waiting for telnet connection on port 23...");
if ((conn = accept(sock, (struct sockaddr *) &address,
&addrLength)) < 0) {
logMessage("accept: %s", strerror(errno));
exit(0);
return -1;
}
printf(" got a connection.\n");
close(sock);
telnet_negotiate(conn);
child = forkpty(&masterFd, NULL, NULL, NULL);
if (child < 0) {
logMessage("forkpty: %s", strerror(errno));
close(conn);
return -1;
} else if (child) {
fds[0].events = POLLIN;
fds[0].fd = masterFd;
fds[1].events = POLLIN;
fds[1].fd = conn;
fds[2].events = POLLIN;
fds[2].fd = STDIN_FILENO;
tcgetattr(STDIN_FILENO, &orig);
tcgetattr(STDIN_FILENO, &new);
new.c_lflag &= ~(ICANON | ECHO | ECHOCTL | ECHONL);
new.c_oflag &= ~ONLCR;
new.c_iflag &= ~ICRNL;
new.c_cc[VSUSP] = 0;
tcsetattr(STDIN_FILENO, 0, &new);
while ((i = poll(fds, 3, -1)) > 0) {
if (fds[0].revents) {
i = read(masterFd, buf, sizeof(buf));
/* child died */
if (i < 0)
break;
telnet_send_output(conn, buf, i);
write(STDOUT_FILENO, buf, i);
}
if (fds[1].revents) {
i = read(conn, buf, sizeof(buf));
/* connection went away */
if (!i)
break;
i = telnet_process_input(&ts, buf, i);
write(masterFd, buf, i);
}
if (fds[2].revents) {
i = read(STDIN_FILENO, buf, sizeof(buf));
write(masterFd, buf, i);
}
}
printf("out of poll %d\n", i);
if (i < 0) {
logMessage("poll: %s", strerror(errno));
}
kill(child, SIGTERM);
close(conn);
tcsetattr(STDIN_FILENO, 0, &orig);
exit(0);
}
return 0;
}
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