2009-03-19 06:32:23 +00:00
|
|
|
/*
|
|
|
|
* Sean Middleditch
|
|
|
|
* sean@sourcemud.org
|
|
|
|
*
|
|
|
|
* The author or authors of this code dedicate any and all copyright interest
|
|
|
|
* in this code to the public domain. We make this dedication for the benefit
|
|
|
|
* of the public at large and to the detriment of our heirs and successors. We
|
|
|
|
* intend this dedication to be an overt act of relinquishment in perpetuity of
|
|
|
|
* all present and future rights to this code under copyright law.
|
|
|
|
*/
|
|
|
|
|
|
|
|
#include <sys/socket.h>
|
|
|
|
#include <netinet/in.h>
|
|
|
|
#include <arpa/inet.h>
|
|
|
|
#include <poll.h>
|
|
|
|
#include <errno.h>
|
|
|
|
#include <stdio.h>
|
|
|
|
#include <string.h>
|
|
|
|
#include <stdlib.h>
|
|
|
|
#include <ctype.h>
|
|
|
|
#include <unistd.h>
|
|
|
|
|
|
|
|
#ifdef HAVE_ZLIB
|
|
|
|
#include "zlib.h"
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#include "libtelnet.h"
|
|
|
|
|
|
|
|
#define MAX_USERS 64
|
|
|
|
#define LINEBUFFER_SIZE 256
|
|
|
|
|
|
|
|
struct user_t {
|
|
|
|
char *name;
|
|
|
|
int sock;
|
|
|
|
telnet_t telnet;
|
|
|
|
char linebuf[256];
|
|
|
|
int linepos;
|
|
|
|
};
|
|
|
|
|
|
|
|
static struct user_t users[MAX_USERS];
|
|
|
|
|
|
|
|
static void linebuffer_push(char *buffer, size_t size, int *linepos,
|
|
|
|
char ch, void (*cb)(const char *line, int overflow, void *ud),
|
|
|
|
void *ud) {
|
|
|
|
|
|
|
|
/* CRLF -- line terminator */
|
|
|
|
if (ch == '\n' && *linepos > 0 && buffer[*linepos - 1] == '\r') {
|
|
|
|
/* NUL terminate (replaces \r in buffer), notify app, clear */
|
|
|
|
buffer[*linepos - 1] = 0;
|
|
|
|
cb(buffer, 0, ud);
|
|
|
|
*linepos = 0;
|
|
|
|
|
|
|
|
/* CRNUL -- just a CR */
|
|
|
|
} else if (ch == 0 && *linepos > 0 && buffer[*linepos - 1] == '\r') {
|
|
|
|
/* do nothing, the CR is already in the buffer */
|
|
|
|
|
|
|
|
/* anything else (including technically invalid CR followed by
|
|
|
|
* anything besides LF or NUL -- just buffer if we have room
|
|
|
|
* \r
|
|
|
|
*/
|
|
|
|
} else if (*linepos != size) {
|
|
|
|
buffer[(*linepos)++] = ch;
|
|
|
|
|
|
|
|
/* buffer overflow */
|
|
|
|
} else {
|
|
|
|
/* terminate (NOTE: eats a byte), notify app, clear buffer */
|
|
|
|
buffer[size - 1] = 0;
|
|
|
|
cb(buffer, size - 1, ud);
|
|
|
|
*linepos = 0;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
static void _message(const char *from, const char *msg) {
|
|
|
|
int i;
|
|
|
|
for (i = 0; i != MAX_USERS; ++i) {
|
|
|
|
if (users[i].sock != -1) {
|
|
|
|
telnet_printf(&users[i].telnet, "%s: %s\n", from, msg);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
static void _send(int sock, const char *buffer, unsigned int size) {
|
|
|
|
int rs;
|
|
|
|
|
|
|
|
/* ignore on invalid socket */
|
|
|
|
if (sock == -1)
|
|
|
|
return;
|
|
|
|
|
|
|
|
/* send data */
|
|
|
|
while (size > 0) {
|
|
|
|
if ((rs = send(sock, buffer, size, 0)) == -1) {
|
|
|
|
if (errno != EINTR && errno != ECONNRESET) {
|
|
|
|
fprintf(stderr, "send() failed: %s\n", strerror(errno));
|
|
|
|
exit(1);
|
|
|
|
} else {
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
} else if (rs == 0) {
|
|
|
|
fprintf(stderr, "send() unexpectedly returned 0\n");
|
|
|
|
exit(1);
|
|
|
|
}
|
|
|
|
|
|
|
|
/* update pointer and size to see if we've got more to send */
|
|
|
|
buffer += rs;
|
|
|
|
size -= rs;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
/* process input line */
|
|
|
|
static void _online(const char *line, int overflow, void *ud) {
|
|
|
|
struct user_t *user = (struct user_t*)ud;
|
|
|
|
int i;
|
|
|
|
|
|
|
|
/* if the user has no name, this is his "login" */
|
|
|
|
if (user->name == 0) {
|
|
|
|
/* must not be empty, must be at least 32 chars */
|
|
|
|
if (strlen(line) == 0 || strlen(line) > 32) {
|
|
|
|
telnet_printf(&user->telnet, "Invalid name.\nEnter name: ");
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* must not already be in use */
|
|
|
|
for (i = 0; i != MAX_USERS; ++i) {
|
|
|
|
if (users[i].name != 0 && strcmp(users[i].name, line) == 0) {
|
|
|
|
telnet_printf(&user->telnet, "Name in use.\nEnter name: ");
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
/* keep name */
|
|
|
|
user->name = strdup(line);
|
|
|
|
telnet_printf(&user->telnet, "Welcome, %s!\n", line);
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* if line is "quit" then, well, quit */
|
|
|
|
if (strcmp(line, "quit") == 0) {
|
|
|
|
close(user->sock);
|
|
|
|
user->sock = -1;
|
|
|
|
_message(user->name, "** HAS QUIT **");
|
|
|
|
free(user->name);
|
|
|
|
user->name = 0;
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* just a message -- send to all users */
|
|
|
|
_message(user->name, line);
|
|
|
|
}
|
|
|
|
|
|
|
|
static void _input(struct user_t *user, const char *buffer,
|
|
|
|
unsigned int size) {
|
|
|
|
unsigned int i;
|
|
|
|
for (i = 0; i != size; ++i)
|
|
|
|
linebuffer_push(user->linebuf, sizeof(user->linebuf), &user->linepos,
|
|
|
|
(char)buffer[i], _online, user);
|
|
|
|
}
|
|
|
|
|
|
|
|
static void _event_handler(telnet_t *telnet, telnet_event_t *ev,
|
|
|
|
void *user_data) {
|
|
|
|
struct user_t *user = (struct user_t*)user_data;
|
|
|
|
|
|
|
|
switch (ev->type) {
|
|
|
|
/* data received */
|
|
|
|
case TELNET_EV_DATA:
|
|
|
|
_input(user, ev->buffer, ev->size);
|
|
|
|
break;
|
|
|
|
/* data must be sent */
|
|
|
|
case TELNET_EV_SEND:
|
|
|
|
_send(user->sock, ev->buffer, ev->size);
|
|
|
|
break;
|
2009-03-19 19:16:32 +00:00
|
|
|
/* enable compress2 if accepted by client */
|
|
|
|
case TELNET_EV_DO:
|
|
|
|
if (ev->telopt == TELNET_TELOPT_COMPRESS2)
|
|
|
|
telnet_begin_compress2(telnet);
|
|
|
|
break;
|
2009-03-19 06:32:23 +00:00
|
|
|
/* error */
|
|
|
|
case TELNET_EV_ERROR:
|
|
|
|
close(user->sock);
|
|
|
|
user->sock = -1;
|
|
|
|
if (user->name != 0) {
|
|
|
|
_message(user->name, "** HAS HAD AN ERROR **");
|
|
|
|
free(user->name);
|
|
|
|
user->name = 0;
|
|
|
|
}
|
|
|
|
telnet_free(&user->telnet);
|
|
|
|
break;
|
|
|
|
default:
|
|
|
|
/* ignore */
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
int main(int argc, char **argv) {
|
|
|
|
char buffer[512];
|
|
|
|
short listen_port;
|
|
|
|
int listen_sock;
|
|
|
|
int rs;
|
|
|
|
int i;
|
|
|
|
struct sockaddr_in addr;
|
|
|
|
socklen_t addrlen;
|
|
|
|
struct pollfd pfd[MAX_USERS + 1];
|
|
|
|
|
|
|
|
/* check usage */
|
|
|
|
if (argc != 2) {
|
|
|
|
fprintf(stderr, "Usage:\n ./telnet-chatd <port>\n");
|
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* initialize data structures */
|
|
|
|
memset(&pfd, 0, sizeof(pfd));
|
|
|
|
memset(users, 0, sizeof(users));
|
|
|
|
for (i = 0; i != MAX_USERS; ++i)
|
|
|
|
users[i].sock = -1;
|
|
|
|
|
|
|
|
/* parse listening port */
|
|
|
|
listen_port = strtol(argv[1], 0, 10);
|
|
|
|
|
|
|
|
/* create listening socket */
|
|
|
|
if ((listen_sock = socket(AF_INET, SOCK_STREAM, 0)) == -1) {
|
|
|
|
fprintf(stderr, "socket() failed: %s\n", strerror(errno));
|
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* reuse address option */
|
|
|
|
rs = 1;
|
|
|
|
setsockopt(listen_sock, SOL_SOCKET, SO_REUSEADDR, &rs, sizeof(rs));
|
|
|
|
|
|
|
|
/* bind to listening addr/port */
|
|
|
|
memset(&addr, 0, sizeof(addr));
|
|
|
|
addr.sin_family = AF_INET;
|
|
|
|
addr.sin_addr.s_addr = INADDR_ANY;
|
|
|
|
addr.sin_port = htons(listen_port);
|
|
|
|
if (bind(listen_sock, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
|
|
|
|
fprintf(stderr, "bind() failed: %s\n", strerror(errno));
|
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* listen for clients */
|
|
|
|
if (listen(listen_sock, 5) == -1) {
|
|
|
|
fprintf(stderr, "listen() failed: %s\n", strerror(errno));
|
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
|
|
|
|
printf("LISTENING ON PORT %d\n", listen_port);
|
|
|
|
|
|
|
|
/* initialize listening descriptors */
|
|
|
|
pfd[MAX_USERS].fd = listen_sock;
|
|
|
|
pfd[MAX_USERS].events = POLLIN;
|
|
|
|
|
|
|
|
/* loop for ever */
|
|
|
|
for (;;) {
|
|
|
|
/* prepare for poll */
|
|
|
|
for (i = 0; i != MAX_USERS; ++i) {
|
|
|
|
if (users[i].sock != -1) {
|
|
|
|
pfd[i].fd = users[i].sock;
|
|
|
|
pfd[i].events = POLLIN;
|
|
|
|
} else {
|
|
|
|
pfd[i].fd = -1;
|
|
|
|
pfd[i].events = 0;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
/* poll */
|
|
|
|
rs = poll(pfd, MAX_USERS + 1, -1);
|
|
|
|
if (rs == -1 && errno != EINTR) {
|
|
|
|
fprintf(stderr, "poll() failed: %s\n", strerror(errno));
|
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* new connection */
|
|
|
|
if (pfd[MAX_USERS].revents & POLLIN) {
|
|
|
|
/* acept the sock */
|
|
|
|
addrlen = sizeof(addr);
|
|
|
|
if ((rs = accept(listen_sock, (struct sockaddr *)&addr,
|
|
|
|
&addrlen)) == -1) {
|
|
|
|
fprintf(stderr, "accept() failed: %s\n", strerror(errno));
|
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
|
|
|
|
printf("Connection received.\n");
|
|
|
|
|
|
|
|
/* find a free user */
|
|
|
|
for (i = 0; i != MAX_USERS; ++i)
|
|
|
|
if (users[i].sock == -1)
|
|
|
|
break;
|
|
|
|
if (i == MAX_USERS) {
|
|
|
|
printf(" rejected (too many users)\n");
|
|
|
|
_send(rs, "Too many users.\r\n", 14);
|
|
|
|
close(rs);
|
|
|
|
}
|
|
|
|
|
|
|
|
/* init, welcome */
|
|
|
|
users[i].sock = rs;
|
|
|
|
telnet_init(&users[i].telnet, _event_handler, 0, &users[i]);
|
2009-03-21 03:08:55 +00:00
|
|
|
telnet_negotiate(&users[i].telnet, TELNET_WILL,
|
2009-03-19 19:16:32 +00:00
|
|
|
TELNET_TELOPT_COMPRESS2);
|
2009-03-19 06:32:23 +00:00
|
|
|
telnet_printf(&users[i].telnet, "Enter name: ");
|
|
|
|
}
|
|
|
|
|
|
|
|
/* read from client */
|
|
|
|
for (i = 0; i != MAX_USERS; ++i) {
|
|
|
|
/* skip users that aren't actually connected */
|
|
|
|
if (users[i].sock == -1)
|
|
|
|
continue;
|
|
|
|
|
|
|
|
if (pfd[i].revents & POLLIN) {
|
|
|
|
if ((rs = recv(users[i].sock, buffer, sizeof(buffer), 0)) > 0) {
|
2009-03-21 03:08:55 +00:00
|
|
|
telnet_recv(&users[i].telnet, buffer, rs);
|
2009-03-19 06:32:23 +00:00
|
|
|
} else if (rs == 0) {
|
|
|
|
printf("Connection closed.\n");
|
|
|
|
close(users[i].sock);
|
|
|
|
if (users[i].name != 0) {
|
|
|
|
_message(users[i].name, "** HAS DISCONNECTED **");
|
|
|
|
free(users[i].name);
|
|
|
|
users[i].name = 0;
|
|
|
|
}
|
|
|
|
telnet_free(&users[i].telnet);
|
|
|
|
users[i].sock = -1;
|
|
|
|
break;
|
|
|
|
} else if (errno != EINTR) {
|
|
|
|
fprintf(stderr, "recv(client) failed: %s\n",
|
|
|
|
strerror(errno));
|
|
|
|
exit(1);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
/* not that we can reach this, but GCC will cry if it's not here */
|
|
|
|
return 0;
|
|
|
|
}
|