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#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include "server.h"
#include "session.h"
#include "socktool.h"
#include "basic-list.h"
#include <errno.h>
#include <locale.h>
#include <time.h>
#include <signal.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/select.h>
#include <sys/socket.h>
#include <sys/wait.h>
#include <unistd.h>
static volatile sig_atomic_t quit_request = false;
static void quit_request_setter (int signo) {
quit_request = true;
}
static void cleanup_child (int signo) {
while (waitpid (-1, NULL, WUNTRACED | WNOHANG) > 0);
}
static void svrlist_fill_rset (List* svrlist, fd_set* rset, int* maxfd) {
ListNode* iter;
for (iter = list_node_front (svrlist); iter != NULL; iter = list_next (iter)) {
RasServer* server = RAS_SERVER (list_data (iter));
RasConn* conn = RAS_CONN (server);
if (conn->fd_is_set) {
FD_SET (conn->fd, rset);
*maxfd = xmax (*maxfd, conn->fd) + 1;
}
}
}
static RasServer* svrlist_find_server (List* svrlist, int fd) {
ListNode* iter;
for (iter = list_node_front (svrlist); iter != NULL; iter = list_next (iter)) {
RasServer* server = RAS_SERVER (list_data (iter));
RasConn* conn = RAS_CONN (server);
if (conn->fd_is_set && conn->fd == fd) {
return server;
}
}
return NULL;
}
int main (int argc, char* argv[]) {
setlocale (LC_ALL, "");
tzset ();
if (argc < 2) {
fprintf (stderr, "Usage: %s port\n", argv[0]);
return 1;
}
struct sigaction action = {
.sa_handler = SIG_IGN,
.sa_flags = 0
};
sigemptyset (&action.sa_mask);
sigaction (SIGPIPE, &action, NULL);
action.sa_handler = cleanup_child;
sigaction (SIGCHLD, &action, NULL);
action.sa_handler = quit_request_setter;
sigaction (SIGINT, &action, NULL);
sigaction (SIGQUIT, &action, NULL);
sigaction (SIGTERM, &action, NULL);
List* svrlist = list_create ();
int sid = 0, cid = 0;
RasServer svr;
ras_server_init (&svr, RAS_CONN_PERM_ADMIN, AF_LOCAL, NULL, sid), sid++;
if (ras_server_listen (&svr, "/tmp/ras-server.sock", 0600) < 0) {
return 1;
} else {
list_pushback (svrlist, &svr, sizeof (RasServer));
}
ras_server_init (&svr, RAS_CONN_PERM_RESTRICTED, AF_INET, NULL, sid), sid++;
if (ras_server_listen (&svr, NULL, atoi (argv[1])) < 0) {
return 1;
} else {
list_pushback (svrlist, &svr, sizeof (RasServer));
}
ras_server_init (&svr, RAS_CONN_PERM_RESTRICTED, AF_INET6, NULL, sid), sid++;
if (ras_server_listen (&svr, NULL, atoi (argv[1])) < 0) {
return 1;
} else {
list_pushback (svrlist, &svr, sizeof (RasServer));
}
int maxfd;
fd_set rset, wset;
while (!quit_request) {
int rval;
maxfd = 0;
FD_ZERO (&rset);
FD_ZERO (&wset);
svrlist_fill_rset (svrlist, &rset, &maxfd);
rval = select (maxfd, &rset, &wset, NULL, NULL);
if (rval < 0) {
continue;
}
for (int i = 0; i < maxfd; i++) {
if (FD_ISSET (i, &rset)) {
RasServer* server = svrlist_find_server (svrlist, i);
if (server == NULL) {
continue;
}
RasSession session;
int session_fd;
char* peername;
pid_t cpid;
session_fd = accept (i, NULL, NULL);
if (session_fd < 0) {
continue;
}
peername = ras_socktool_get_peername (session_fd);
ras_server_log (server,
"client %d from %s is accepted", cid, peername);
free (peername);
cpid = fork ();
if (cpid < 0) {
ras_server_log (server,
"client %d cannot continue: fork error: %s",
cid, strerror (errno));
close (session_fd);
ras_server_log (server,
"client %d connection closed", cid);
continue;
} else if (cpid > 0) {
/* parent process: just close the accepted fd */
ras_server_log (server,
"client %d is handled by process %u now", cid, cpid);
cid++;
close (session_fd);
} else {
/* child process: we need to reset signal handlers */
struct sigaction session_action = {
.sa_handler = SIG_DFL,
.sa_flags = 0
};
sigemptyset (&session_action.sa_mask);
sigaction (SIGINT, &action, NULL);
sigaction (SIGQUIT, &action, NULL);
sigaction (SIGTERM, &action, NULL);
if (ras_session_init (&session, server, session_fd, cid) < 0) {
ras_session_destroy (&session);
exit (1);
}
if (ras_session_read_header (&session) < 0) {
ras_session_destroy (&session);
exit (1);
}
if (ras_session_start_shell (&session) < 0) {
ras_session_destroy (&session);
exit (1);
}
ras_session_destroy (&session);
exit (0);
}
}
}
}
puts ("Shutting down all servers ...");
for (ListNode* iter = list_node_front (svrlist);
iter != NULL; iter = list_next (iter))
{
ras_server_destroy (RAS_SERVER (list_data (iter)));
}
list_free (svrlist);
puts ("Exited");
return 0;
}
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