/* wait for the result of a non-blocking connect */
static int connect_wait(CLI *c, int fd, int timeout) {
int error;
socklen_t optlen;
s_log(LOG_DEBUG, "connect_wait: waiting %d seconds", timeout);
s_poll_zero(&c->fds);
s_poll_add(&c->fds, fd, 1, 1);
switch(s_poll_wait(&c->fds, timeout)) {
case -1:
sockerror("connect_wait: s_poll_wait");
return -1; /* error */
case 0:
s_log(LOG_INFO, "connect_wait: s_poll_wait timeout");
return -1; /* error */
default:
if(s_poll_canread(&c->fds, fd)) {
/* just connected socket should not be ready for read */
/* get the resulting error code, now */
optlen=sizeof(error);
if(!getsockopt(fd, SOL_SOCKET, SO_ERROR, (void *)&error, &optlen))
errno=error;
if(errno) { /* really an error? */
sockerror("connect_wait: getsockopt");
return -1; /* connection failed */
}
}
if(s_poll_canwrite(&c->fds, fd)) {
s_log(LOG_DEBUG, "connect_wait: connected");
return 0; /* success */
}
s_log(LOG_ERR, "connect_wait: unexpected s_poll_wait result");
return -1; /* unexpected result */
}
return -1; /* should not be possible */
}
void read_blocking(CLI *c, int fd, u8 *ptr, int len) {
/* simulate a blocking read */
s_poll_set fds;
int num;
while(len>0) {
s_poll_zero(&fds);
s_poll_add(&fds, fd, 1, 0); /* read */
switch(s_poll_wait(&fds, c->opt->timeout_busy)) {
case -1:
sockerror("read_blocking: s_poll_wait");
longjmp(c->err, 1); /* error */
case 0:
s_log(LOG_INFO, "read_blocking: s_poll_wait timeout");
longjmp(c->err, 1); /* timeout */
case 1:
break; /* OK */
default:
s_log(LOG_ERR, "read_blocking: s_poll_wait unknown result");
longjmp(c->err, 1); /* error */
}
num=readsocket(fd, ptr, len);
switch(num) {
case -1: /* error */
sockerror("readsocket (read_blocking)");
longjmp(c->err, 1);
case 0: /* EOF */
s_log(LOG_ERR, "Unexpected socket close (read_blocking)");
longjmp(c->err, 1);
}
ptr+=num;
len-=num;
}
}
void write_blocking(CLI *c, int fd, u8 *ptr, int len) {
/* simulate a blocking write */
s_poll_set fds;
int num;
while(len>0) {
s_poll_zero(&fds);
s_poll_add(&fds, fd, 0, 1); /* write */
switch(s_poll_wait(&fds, c->opt->timeout_busy)) {
case -1:
sockerror("write_blocking: s_poll_wait");
longjmp(c->err, 1); /* error */
case 0:
s_log(LOG_INFO, "write_blocking: s_poll_wait timeout");
longjmp(c->err, 1); /* timeout */
case 1:
break; /* OK */
default:
s_log(LOG_ERR, "write_blocking: s_poll_wait unknown result");
longjmp(c->err, 1); /* error */
}
num=writesocket(fd, ptr, len);
switch(num) {
case -1: /* error */
sockerror("writesocket (write_blocking)");
longjmp(c->err, 1);
}
ptr+=num;
len-=num;
}
}
static int RFC2487(CLI *c, int fd) {
s_poll_zero(&c->fds);
s_poll_add(&c->fds, fd, 1, 0);
switch(s_poll_wait(&c->fds, 0)) {
case 0: /* fd not ready to read */
s_log(LOG_DEBUG, "RFC 2487 detected");
return 1;
case 1: /* fd ready to read */
s_log(LOG_DEBUG, "RFC 2487 not detected");
return 0;
default: /* -1 */
sockerror("RFC2487 (s_poll_wait)");
return -1;
}
}
void fdgetline(CLI *c, int fd, char *line) {
char logline[STRLEN];
s_poll_set fds;
int ptr;
for(ptr=0;;) {
s_poll_zero(&fds);
s_poll_add(&fds, fd, 1, 0); /* read */
switch(s_poll_wait(&fds, c->opt->timeout_busy)) {
case -1:
sockerror("fdgetline: s_poll_wait");
longjmp(c->err, 1); /* error */
case 0:
s_log(LOG_INFO, "fdgetline: s_poll_wait timeout");
longjmp(c->err, 1); /* timeout */
case 1:
break; /* OK */
default:
s_log(LOG_ERR, "fdgetline: s_poll_wait unknown result");
longjmp(c->err, 1); /* error */
}
switch(readsocket(fd, line+ptr, 1)) {
case -1: /* error */
sockerror("readsocket (fdgetline)");
longjmp(c->err, 1);
case 0: /* EOF */
s_log(LOG_ERR, "Unexpected socket close (fdgetline)");
longjmp(c->err, 1);
}
if(line[ptr]=='\r')
continue;
if(line[ptr]=='\n')
break;
if(!line[ptr])
break;
if(++ptr==STRLEN) {
s_log(LOG_ERR, "Input line too long");
longjmp(c->err, 1);
}
}
line[ptr]='\0';
safecopy(logline, line);
safestring(logline);
s_log(LOG_DEBUG, " <- %s", logline);
}
/****************************** transfer data */
static int transfer(CLI *c) {
int num, err;
int check_SSL_pending;
enum {CL_OPEN, CL_INIT, CL_RETRY, CL_CLOSED} ssl_closing=CL_OPEN;
int watchdog=0; /* a counter to detect an infinite loop */
c->sock_ptr=c->ssl_ptr=0;
sock_rd=sock_wr=ssl_rd=ssl_wr=1;
c->sock_bytes=c->ssl_bytes=0;
do { /* main loop */
/* set flag to try and read any buffered SSL data
* if we made room in the buffer by writing to the socket */
check_SSL_pending=0;
/****************************** setup c->fds structure */
s_poll_zero(&c->fds); /* Initialize the structure */
if(sock_rd && c->sock_ptr<BUFFSIZE) /* socket input buffer not full*/
s_poll_add(&c->fds, c->sock_rfd->fd, 1, 0);
if((ssl_rd && c->ssl_ptr<BUFFSIZE) || /* SSL input buffer not full */
((c->sock_ptr || ssl_closing==CL_RETRY) && want_rd))
/* want to SSL_write or SSL_shutdown but read from the
* underlying socket needed for the SSL protocol */
s_poll_add(&c->fds, c->ssl_rfd->fd, 1, 0);
if(c->ssl_ptr) /* SSL input buffer not empty */
s_poll_add(&c->fds, c->sock_wfd->fd, 0, 1);
if(c->sock_ptr || /* socket input buffer not empty */
ssl_closing==CL_INIT /* need to send close_notify */ ||
((c->ssl_ptr<BUFFSIZE || ssl_closing==CL_RETRY) && want_wr))
/* want to SSL_read or SSL_shutdown but write to the
* underlying socket needed for the SSL protocol */
s_poll_add(&c->fds, c->ssl_wfd->fd, 0, 1);
/****************************** wait for an event */
err=s_poll_wait(&c->fds, (sock_rd && ssl_rd) /* both peers open */ ||
c->ssl_ptr /* data buffered to write to socket */ ||
c->sock_ptr /* data buffered to write to SSL */ ?
c->opt->timeout_idle : c->opt->timeout_close);
switch(err) {
case -1:
sockerror("transfer: s_poll_wait");
return -1;
case 0: /* timeout */
if((sock_rd && ssl_rd) || c->ssl_ptr || c->sock_ptr) {
s_log(LOG_INFO, "s_poll_wait timeout: connection reset");
return -1;
} else { /* already closing connection */
s_log(LOG_INFO, "s_poll_wait timeout: connection close");
return 0; /* OK */
}
}
if(!(sock_can_rd || sock_can_wr || ssl_can_rd || ssl_can_wr)) {
s_log(LOG_ERR, "INTERNAL ERROR: "
"s_poll_wait returned %d, but no descriptor is ready", err);
return -1;
}
/****************************** send SSL close_notify message */
if(ssl_closing==CL_INIT || (ssl_closing==CL_RETRY &&
((want_rd && ssl_can_rd) || (want_wr && ssl_can_wr)))) {
switch(SSL_shutdown(c->ssl)) { /* Send close_notify */
case 1: /* the shutdown was successfully completed */
s_log(LOG_INFO, "SSL_shutdown successfully sent close_notify");
ssl_closing=CL_CLOSED; /* done! */
break;
case 0: /* the shutdown is not yet finished */
s_log(LOG_DEBUG, "SSL_shutdown retrying");
ssl_closing=CL_RETRY; /* retry next time */
break;
case -1: /* a fatal error occurred */
sslerror("SSL_shutdown");
return -1;
}
}
/****************************** write to socket */
if(sock_wr && sock_can_wr) {
/* for stunnel to tell web server the remote ip address */
add_remote_ip_to_header(c);
num=writesocket(c->sock_wfd->fd, c->ssl_buff, c->ssl_ptr);
switch(num) {
case -1: /* error */
if(parse_socket_error("writesocket"))
return -1;
break;
case 0:
s_log(LOG_DEBUG, "No data written to the socket: retrying");
break;
default:
memmove(c->ssl_buff, c->ssl_buff+num, c->ssl_ptr-num);
if(c->ssl_ptr==BUFFSIZE) /* buffer was previously full */
check_SSL_pending=1; /* check for data buffered by SSL */
c->ssl_ptr-=num;
c->sock_bytes+=num;
watchdog=0; /* reset watchdog */
}
}
/****************************** write to SSL */
if(ssl_wr && c->sock_ptr && ( /* output buffer not empty */
ssl_can_wr || (want_rd && ssl_can_rd)
/* SSL_write wants to read from the underlying descriptor */
)) {
num=SSL_write(c->ssl, c->sock_buff, c->sock_ptr);
switch(err=SSL_get_error(c->ssl, num)) {
case SSL_ERROR_NONE:
memmove(c->sock_buff, c->sock_buff+num, c->sock_ptr-num);
c->sock_ptr-=num;
c->ssl_bytes+=num;
watchdog=0; /* reset watchdog */
break;
case SSL_ERROR_WANT_WRITE:
s_log(LOG_DEBUG, "SSL_write returned WANT_WRITE: retrying");
break;
case SSL_ERROR_WANT_READ:
s_log(LOG_DEBUG, "SSL_write returned WANT_READ: retrying");
break;
case SSL_ERROR_WANT_X509_LOOKUP:
s_log(LOG_DEBUG,
"SSL_write returned WANT_X509_LOOKUP: retrying");
break;
case SSL_ERROR_SYSCALL: /* really an error */
if(num && parse_socket_error("SSL_write"))
return -1;
break;
case SSL_ERROR_ZERO_RETURN: /* close_notify received */
s_log(LOG_DEBUG, "SSL closed on SSL_write");
ssl_rd=0;
break;
case SSL_ERROR_SSL:
sslerror("SSL_write");
return -1;
default:
s_log(LOG_ERR, "SSL_write/SSL_get_error returned %d", err);
return -1;
}
}
/****************************** read from socket */
if(sock_rd && sock_can_rd) {
num=readsocket(c->sock_rfd->fd,
c->sock_buff+c->sock_ptr, BUFFSIZE-c->sock_ptr);
switch(num) {
case -1:
if(parse_socket_error("readsocket"))
return -1;
break;
case 0: /* close */
s_log(LOG_DEBUG, "Socket closed on read");
sock_rd=0;
break;
default:
c->sock_ptr+=num;
watchdog=0; /* reset watchdog */
}
}
/****************************** read from SSL */
if(ssl_rd && c->ssl_ptr<BUFFSIZE && ( /* input buffer not full */
ssl_can_rd || (want_wr && ssl_can_wr) ||
/* SSL_read wants to write to the underlying descriptor */
(check_SSL_pending && SSL_pending(c->ssl))
/* write made space from full buffer */
)) {
num=SSL_read(c->ssl, c->ssl_buff+c->ssl_ptr, BUFFSIZE-c->ssl_ptr);
switch(err=SSL_get_error(c->ssl, num)) {
case SSL_ERROR_NONE:
c->ssl_ptr+=num;
watchdog=0; /* reset watchdog */
break;
case SSL_ERROR_WANT_WRITE:
s_log(LOG_DEBUG, "SSL_read returned WANT_WRITE: retrying");
break;
case SSL_ERROR_WANT_READ:
s_log(LOG_DEBUG, "SSL_read returned WANT_READ: retrying");
break;
case SSL_ERROR_WANT_X509_LOOKUP:
s_log(LOG_DEBUG,
"SSL_read returned WANT_X509_LOOKUP: retrying");
break;
case SSL_ERROR_SYSCALL:
if(!num) { /* EOF */
if(c->sock_ptr) {
s_log(LOG_ERR,
"SSL socket closed with %d byte(s) in buffer",
c->sock_ptr);
return -1; /* reset the socket */
}
s_log(LOG_DEBUG, "SSL socket closed on SSL_read");
ssl_rd=ssl_wr=0; /* buggy or SSLv2 peer: no close_notify */
ssl_closing=CL_CLOSED; /* don't try to send it back */
} else if(parse_socket_error("SSL_read"))
return -1;
break;
case SSL_ERROR_ZERO_RETURN: /* close_notify received */
s_log(LOG_DEBUG, "SSL closed on SSL_read");
ssl_rd=0;
break;
case SSL_ERROR_SSL:
sslerror("SSL_read");
return -1;
default:
s_log(LOG_ERR, "SSL_read/SSL_get_error returned %d", err);
return -1;
}
}
/****************************** check write shutdown conditions */
if(sock_wr && !ssl_rd && !c->ssl_ptr) {
s_log(LOG_DEBUG, "Socket write shutdown");
sock_wr=0; /* no further write allowed */
shutdown(c->sock_wfd->fd, SHUT_WR); /* send TCP FIN */
}
if(ssl_wr && (!sock_rd || SSL_get_shutdown(c->ssl)) && !c->sock_ptr) {
s_log(LOG_DEBUG, "SSL write shutdown");
ssl_wr=0; /* no further write allowed */
if(strcmp(SSL_get_version(c->ssl), "SSLv2")) { /* SSLv3, TLSv1 */
ssl_closing=CL_INIT; /* initiate close_notify */
} else { /* no alerts in SSLv2 including close_notify alert */
shutdown(c->sock_rfd->fd, SHUT_RD); /* notify the kernel */
shutdown(c->sock_wfd->fd, SHUT_WR); /* send TCP FIN */
SSL_set_shutdown(c->ssl, /* notify the OpenSSL library */
SSL_SENT_SHUTDOWN|SSL_RECEIVED_SHUTDOWN);
ssl_rd=0; /* no further read allowed */
ssl_closing=CL_CLOSED; /* closed */
}
}
if(ssl_closing==CL_RETRY) { /* SSL shutdown */
if(!want_rd && !want_wr) { /* close_notify alert was received */
s_log(LOG_DEBUG, "SSL doesn't need to read or write");
ssl_closing=CL_CLOSED;
}
if(watchdog>5) {
s_log(LOG_NOTICE, "Too many retries on SSL shutdown");
ssl_closing=CL_CLOSED;
}
}
/****************************** check watchdog */
if(++watchdog>100) { /* loop executes without transferring any data */
s_log(LOG_ERR,
"transfer() loop executes not transferring any data");
s_log(LOG_ERR,
"please report the problem to [email protected]");
s_log(LOG_ERR, "socket open: rd=%s wr=%s, ssl open: rd=%s wr=%s",
sock_rd ? "yes" : "no", sock_wr ? "yes" : "no",
ssl_rd ? "yes" : "no", ssl_wr ? "yes" : "no");
s_log(LOG_ERR, "socket ready: rd=%s wr=%s, ssl ready: rd=%s wr=%s",
sock_can_rd ? "yes" : "no", sock_can_wr ? "yes" : "no",
ssl_can_rd ? "yes" : "no", ssl_can_wr ? "yes" : "no");
s_log(LOG_ERR, "ssl want: rd=%s wr=%s",
want_rd ? "yes" : "no", want_wr ? "yes" : "no");
s_log(LOG_ERR, "socket input buffer: %d byte(s), "
"ssl input buffer: %d byte(s)", c->sock_ptr, c->ssl_ptr);
s_log(LOG_ERR, "check_SSL_pending=%d, ssl_closing=%d",
check_SSL_pending, ssl_closing);
return -1;
}
} while(sock_wr || ssl_closing!=CL_CLOSED);
return 0; /* OK */
}
static int init_ssl(CLI *c) {
int i, err;
SSL_SESSION *old_session;
if(!(c->ssl=SSL_new(ctx))) {
sslerror("SSL_new");
return -1;
}
#if SSLEAY_VERSION_NUMBER >= 0x0922
SSL_set_session_id_context(c->ssl, sid_ctx, strlen(sid_ctx));
#endif
if(options.option.client) {
if(c->opt->session) {
enter_critical_section(CRIT_SESSION);
SSL_set_session(c->ssl, c->opt->session);
leave_critical_section(CRIT_SESSION);
}
SSL_set_fd(c->ssl, c->remote_fd.fd);
SSL_set_connect_state(c->ssl);
} else {
if(c->local_rfd.fd==c->local_wfd.fd)
SSL_set_fd(c->ssl, c->local_rfd.fd);
else {
/* Does it make sence to have SSL on STDIN/STDOUT? */
SSL_set_rfd(c->ssl, c->local_rfd.fd);
SSL_set_wfd(c->ssl, c->local_wfd.fd);
}
SSL_set_accept_state(c->ssl);
}
/* Setup some values for transfer() function */
if(options.option.client) {
c->sock_rfd=&(c->local_rfd);
c->sock_wfd=&(c->local_wfd);
c->ssl_rfd=c->ssl_wfd=&(c->remote_fd);
} else {
c->sock_rfd=c->sock_wfd=&(c->remote_fd);
c->ssl_rfd=&(c->local_rfd);
c->ssl_wfd=&(c->local_wfd);
}
while(1) {
if(options.option.client)
i=SSL_connect(c->ssl);
else
i=SSL_accept(c->ssl);
err=SSL_get_error(c->ssl, i);
if(err==SSL_ERROR_NONE)
break; /* ok -> done */
if(err==SSL_ERROR_WANT_READ || err==SSL_ERROR_WANT_WRITE) {
s_poll_zero(&c->fds);
s_poll_add(&c->fds, c->ssl_rfd->fd,
err==SSL_ERROR_WANT_READ,
err==SSL_ERROR_WANT_WRITE);
switch(s_poll_wait(&c->fds, c->opt->timeout_busy)) {
case -1:
sockerror("init_ssl: s_poll_wait");
return -1; /* error */
case 0:
s_log(LOG_INFO, "init_ssl: s_poll_wait timeout");
return -1; /* timeout */
case 1:
break; /* OK */
default:
s_log(LOG_ERR, "init_ssl: s_poll_wait unknown result");
return -1; /* error */
}
continue; /* ok -> retry */
}
if(err==SSL_ERROR_SYSCALL) {
switch(get_last_socket_error()) {
case EINTR:
case EAGAIN:
continue;
}
}
if(options.option.client)
sslerror("SSL_connect");
else
sslerror("SSL_accept");
return -1;
}
if(SSL_session_reused(c->ssl)) {
s_log(LOG_INFO, "SSL %s: previous session reused",
options.option.client ? "connected" : "accepted");
} else { /* a new session was negotiated */
if(options.option.client) {
s_log(LOG_INFO, "SSL connected: new session negotiated");
enter_critical_section(CRIT_SESSION);
old_session=c->opt->session;
c->opt->session=SSL_get1_session(c->ssl); /* store it */
if(old_session)
SSL_SESSION_free(old_session); /* release the old one */
leave_critical_section(CRIT_SESSION);
} else
s_log(LOG_INFO, "SSL accepted: new session negotiated");
print_cipher(c);
}
return 0; /* OK */
}
static void daemon_loop(void) {
SOCKADDR_UNION addr;
s_poll_set fds;
LOCAL_OPTIONS *opt;
get_limits();
s_poll_zero(&fds);
#ifndef USE_WIN32
s_poll_add(&fds, signal_pipe_init(), 1, 0);
#endif
if(!local_options.next) {
s_log(LOG_ERR, "No connections defined in config file");
exit(1);
}
num_clients=0;
/* bind local ports */
for(opt=local_options.next; opt; opt=opt->next) {
if(!opt->option.accept) /* no need to bind this service */
continue;
memcpy(&addr, &opt->local_addr.addr[0], sizeof(SOCKADDR_UNION));
if((opt->fd=socket(addr.sa.sa_family, SOCK_STREAM, 0))<0) {
sockerror("local socket");
exit(1);
}
if(alloc_fd(opt->fd))
exit(1);
if(set_socket_options(opt->fd, 0)<0)
exit(1);
s_ntop(opt->local_address, &addr);
if(bind(opt->fd, &addr.sa, addr_len(addr))) {
s_log(LOG_ERR, "Error binding %s to %s",
opt->servname, opt->local_address);
sockerror("bind");
exit(1);
}
s_log(LOG_DEBUG, "%s bound to %s", opt->servname, opt->local_address);
if(listen(opt->fd, 5)) {
sockerror("listen");
exit(1);
}
#ifdef FD_CLOEXEC
fcntl(opt->fd, F_SETFD, FD_CLOEXEC); /* close socket in child execvp */
#endif
s_poll_add(&fds, opt->fd, 1, 0);
}
#if !defined (USE_WIN32) && !defined (__vms)
if(!(options.option.foreground))
daemonize();
drop_privileges();
create_pid();
#endif /* !defined USE_WIN32 && !defined (__vms) */
/* create exec+connect services */
for(opt=local_options.next; opt; opt=opt->next) {
if(opt->option.accept) /* skip ordinary (accepting) services */
continue;
enter_critical_section(CRIT_CLIENTS); /* for multi-cpu machines */
num_clients++;
leave_critical_section(CRIT_CLIENTS);
create_client(-1, -1, alloc_client_session(opt, -1, -1), client);
}
while(1) {
if(s_poll_wait(&fds, -1)<0) /* non-critical error */
log_error(LOG_INFO, get_last_socket_error(),
"daemon_loop: s_poll_wait");
else
for(opt=local_options.next; opt; opt=opt->next)
if(s_poll_canread(&fds, opt->fd))
accept_connection(opt);
}
s_log(LOG_ERR, "INTERNAL ERROR: End of infinite loop 8-)");
}
