blob: 6defe7e342e99efb2c9aff88e86fc93d8fc3cd88 [file] [log] [blame]
/*
* AF_CUST_UDP/AF_CUST_UDP6 UDP protocol layer
*
* Copyright 2019 HAProxy Technologies, Frédéric Lécaille <flecaille@haproxy.com>
*
* Partial merge by Emeric Brun <ebrun@haproxy.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
*/
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <sys/param.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <netinet/udp.h>
#include <netinet/in.h>
#include <haproxy/fd.h>
#include <haproxy/listener.h>
#include <haproxy/log.h>
#include <haproxy/namespace.h>
#include <haproxy/port_range.h>
#include <haproxy/protocol.h>
#include <haproxy/proto_udp.h>
#include <haproxy/proxy.h>
#include <haproxy/server.h>
#include <haproxy/task.h>
static int udp_bind_listeners(struct protocol *proto, char *errmsg, int errlen);
static int udp_bind_listener(struct listener *listener, char *errmsg, int errlen);
static void udp4_add_listener(struct listener *listener, int port);
static void udp6_add_listener(struct listener *listener, int port);
/* Note: must not be declared <const> as its list will be overwritten */
static struct protocol proto_udp4 = {
.name = "udp4",
.sock_domain = AF_CUST_UDP4,
.sock_type = SOCK_DGRAM,
.sock_prot = IPPROTO_UDP,
.sock_family = AF_INET,
.sock_addrlen = sizeof(struct sockaddr_in),
.l3_addrlen = 32/8,
.accept = NULL,
.connect = NULL,
.bind = udp_bind_listener,
.bind_all = udp_bind_listeners,
.unbind_all = unbind_all_listeners,
.enable_all = enable_all_listeners,
.get_src = udp_get_src,
.get_dst = udp_get_dst,
.pause = udp_pause_listener,
.add = udp4_add_listener,
.listeners = LIST_HEAD_INIT(proto_udp4.listeners),
.nb_listeners = 0,
};
INITCALL1(STG_REGISTER, protocol_register, &proto_udp4);
/* Note: must not be declared <const> as its list will be overwritten */
static struct protocol proto_udp6 = {
.name = "udp6",
.sock_domain = AF_CUST_UDP6,
.sock_type = SOCK_DGRAM,
.sock_prot = IPPROTO_UDP,
.sock_family = AF_INET6,
.sock_addrlen = sizeof(struct sockaddr_in6),
.l3_addrlen = 128/8,
.accept = NULL,
.connect = NULL,
.bind = udp_bind_listener,
.bind_all = udp_bind_listeners,
.unbind_all = unbind_all_listeners,
.enable_all = enable_all_listeners,
.get_src = udp_get_src,
.get_dst = udp_get_dst,
.pause = udp_pause_listener,
.add = udp6_add_listener,
.listeners = LIST_HEAD_INIT(proto_udp6.listeners),
.nb_listeners = 0,
};
INITCALL1(STG_REGISTER, protocol_register, &proto_udp6);
/*
* Retrieves the source address for the socket <fd>, with <dir> indicating
* if we're a listener (=0) or an initiator (!=0). It returns 0 in case of
* success, -1 in case of error. The socket's source address is stored in
* <sa> for <salen> bytes.
*/
int udp_get_src(int fd, struct sockaddr *sa, socklen_t salen, int dir)
{
int ret;
if (dir)
ret = getsockname(fd, sa, &salen);
else
ret = getpeername(fd, sa, &salen);
if (!ret) {
if (sa->sa_family == AF_INET)
sa->sa_family = AF_CUST_UDP4;
else if (sa->sa_family == AF_INET6)
sa->sa_family = AF_CUST_UDP6;
}
return ret;
}
/*
* Retrieves the original destination address for the socket <fd>, with <dir>
* indicating if we're a listener (=0) or an initiator (!=0). In the case of a
* listener, if the original destination address was translated, the original
* address is retrieved. It returns 0 in case of success, -1 in case of error.
* The socket's source address is stored in <sa> for <salen> bytes.
*/
int udp_get_dst(int fd, struct sockaddr *sa, socklen_t salen, int dir)
{
int ret;
if (dir)
ret = getpeername(fd, sa, &salen);
else {
ret = getsockname(fd, sa, &salen);
if (ret < 0)
return ret;
#if defined(USE_TPROXY) && defined(SO_ORIGINAL_DST)
/* For TPROXY and Netfilter's NAT, we can retrieve the original
* IPv4 address before DNAT/REDIRECT. We must not do that with
* other families because v6-mapped IPv4 addresses are still
* reported as v4.
*/
if (((struct sockaddr_storage *)sa)->ss_family == AF_INET
&& getsockopt(fd, SOL_IP, SO_ORIGINAL_DST, sa, &salen) == 0) {
sa->sa_family = AF_CUST_UDP4;
return 0;
}
#endif
}
if (!ret) {
if (sa->sa_family == AF_INET)
sa->sa_family = AF_CUST_UDP4;
else if (sa->sa_family == AF_INET6)
sa->sa_family = AF_CUST_UDP6;
}
return ret;
}
/* This function tries to bind a UDPv4/v6 listener. It may return a warning or
* an error message in <errmsg> if the message is at most <errlen> bytes long
* (including '\0'). Note that <errmsg> may be NULL if <errlen> is also zero.
* The return value is composed from ERR_ABORT, ERR_WARN,
* ERR_ALERT, ERR_RETRYABLE and ERR_FATAL. ERR_NONE indicates that everything
* was alright and that no message was returned. ERR_RETRYABLE means that an
* error occurred but that it may vanish after a retry (eg: port in use), and
* ERR_FATAL indicates a non-fixable error. ERR_WARN and ERR_ALERT do not alter
* the meaning of the error, but just indicate that a message is present which
* should be displayed with the respective level. Last, ERR_ABORT indicates
* that it's pointless to try to start other listeners. No error message is
* returned if errlen is NULL.
*/
int udp_bind_listener(struct listener *listener, char *errmsg, int errlen)
{
__label__ udp_return, udp_close_return;
int fd, err;
const char *msg = NULL;
/* copy listener addr because sometimes we need to switch family */
struct sockaddr_storage addr_inet = listener->addr;
/* force to classic sock family */
addr_inet.ss_family = listener->proto->sock_family;
/* ensure we never return garbage */
if (errlen)
*errmsg = 0;
if (listener->state != LI_ASSIGNED)
return ERR_NONE; /* already bound */
err = ERR_NONE;
/* TODO: Implement reuse fd. Take care that to identify fd to reuse
* listeners uses a special AF_CUST_ family and we MUST consider
* IPPROTO (sockaddr is not enought
*/
fd = my_socketat(listener->netns, listener->proto->sock_family, listener->proto->sock_type, listener->proto->sock_prot);
if (fd == -1) {
err |= ERR_RETRYABLE | ERR_ALERT;
msg = "cannot create listening socket";
goto udp_return;
}
if (fd >= global.maxsock) {
err |= ERR_FATAL | ERR_ABORT | ERR_ALERT;
msg = "not enough free sockets (raise '-n' parameter)";
goto udp_close_return;
}
if (fcntl(fd, F_SETFL, O_NONBLOCK) == -1) {
err |= ERR_FATAL | ERR_ALERT;
msg = "cannot make socket non-blocking";
goto udp_close_return;
}
if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one)) == -1) {
/* not fatal but should be reported */
msg = "cannot do so_reuseaddr";
err |= ERR_ALERT;
}
#ifdef SO_REUSEPORT
/* OpenBSD and Linux 3.9 support this. As it's present in old libc versions of
* Linux, it might return an error that we will silently ignore.
*/
if (global.tune.options & GTUNE_USE_REUSEPORT)
setsockopt(fd, SOL_SOCKET, SO_REUSEPORT, &one, sizeof(one));
#endif
if (listener->options & LI_O_FOREIGN) {
switch (addr_inet.ss_family) {
case AF_INET:
if (1
#if defined(IP_TRANSPARENT)
&& (setsockopt(fd, SOL_IP, IP_TRANSPARENT, &one, sizeof(one)) == -1)
#endif
#if defined(IP_FREEBIND)
&& (setsockopt(fd, SOL_IP, IP_FREEBIND, &one, sizeof(one)) == -1)
#endif
#if defined(IP_BINDANY)
&& (setsockopt(fd, IPPROTO_IP, IP_BINDANY, &one, sizeof(one)) == -1)
#endif
#if defined(SO_BINDANY)
&& (setsockopt(fd, SOL_SOCKET, SO_BINDANY, &one, sizeof(one)) == -1)
#endif
) {
msg = "cannot make listening socket transparent";
err |= ERR_ALERT;
}
break;
case AF_INET6:
if (1
#if defined(IPV6_TRANSPARENT) && defined(SOL_IPV6)
&& (setsockopt(fd, SOL_IPV6, IPV6_TRANSPARENT, &one, sizeof(one)) == -1)
#endif
#if defined(IP_FREEBIND)
&& (setsockopt(fd, SOL_IP, IP_FREEBIND, &one, sizeof(one)) == -1)
#endif
#if defined(IPV6_BINDANY)
&& (setsockopt(fd, IPPROTO_IPV6, IPV6_BINDANY, &one, sizeof(one)) == -1)
#endif
#if defined(SO_BINDANY)
&& (setsockopt(fd, SOL_SOCKET, SO_BINDANY, &one, sizeof(one)) == -1)
#endif
) {
msg = "cannot make listening socket transparent";
err |= ERR_ALERT;
}
break;
}
}
#ifdef SO_BINDTODEVICE
/* Note: this might fail if not CAP_NET_RAW */
if (listener->interface) {
if (setsockopt(fd, SOL_SOCKET, SO_BINDTODEVICE,
listener->interface, strlen(listener->interface) + 1) == -1) {
msg = "cannot bind listener to device";
err |= ERR_WARN;
}
}
#endif
#if defined(IPV6_V6ONLY)
if (listener->options & LI_O_V6ONLY)
setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, &one, sizeof(one));
else if (listener->options & LI_O_V4V6)
setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, &zero, sizeof(zero));
#endif
if (bind(fd, (struct sockaddr *)&addr_inet, listener->proto->sock_addrlen) < 0) {
err |= ERR_RETRYABLE | ERR_ALERT;
msg = "cannot bind socket";
goto udp_close_return;
}
/* the socket is ready */
listener->fd = fd;
listener->state = LI_LISTEN;
if (listener->bind_conf->frontend->mode == PR_MODE_SYSLOG)
fd_insert(fd, listener, syslog_fd_handler,
thread_mask(listener->bind_conf->bind_thread) & all_threads_mask);
else {
err |= ERR_FATAL | ERR_ALERT;
msg = "UDP is not yet supported on this proxy mode";
goto udp_close_return;
}
udp_return:
if (msg && errlen) {
char pn[INET6_ADDRSTRLEN];
addr_to_str(&addr_inet, pn, sizeof(pn));
snprintf(errmsg, errlen, "%s [%s:%d]", msg, pn, get_host_port(&addr_inet));
}
return err;
udp_close_return:
close(fd);
goto udp_return;
}
/* This function creates all UDP sockets bound to the protocol entry <proto>.
* It is intended to be used as the protocol's bind_all() function.
* The sockets will be registered but not added to any fd_set, in order not to
* loose them across the fork(). A call to enable_all_listeners() is needed
* to complete initialization. The return value is composed from ERR_*.
*/
static int udp_bind_listeners(struct protocol *proto, char *errmsg, int errlen)
{
struct listener *listener;
int err = ERR_NONE;
list_for_each_entry(listener, &proto->listeners, proto_list) {
err |= udp_bind_listener(listener, errmsg, errlen);
if (err & ERR_ABORT)
break;
}
return err;
}
/* Add <listener> to the list of udp4 listeners, on port <port>. The
* listener's state is automatically updated from LI_INIT to LI_ASSIGNED.
* The number of listeners for the protocol is updated.
*/
static void udp4_add_listener(struct listener *listener, int port)
{
if (listener->state != LI_INIT)
return;
listener->state = LI_ASSIGNED;
listener->proto = &proto_udp4;
((struct sockaddr_in *)(&listener->addr))->sin_port = htons(port);
LIST_ADDQ(&proto_udp4.listeners, &listener->proto_list);
proto_udp4.nb_listeners++;
}
/* Add <listener> to the list of udp6 listeners, on port <port>. The
* listener's state is automatically updated from LI_INIT to LI_ASSIGNED.
* The number of listeners for the protocol is updated.
*/
static void udp6_add_listener(struct listener *listener, int port)
{
if (listener->state != LI_INIT)
return;
listener->state = LI_ASSIGNED;
listener->proto = &proto_udp6;
((struct sockaddr_in *)(&listener->addr))->sin_port = htons(port);
LIST_ADDQ(&proto_udp6.listeners, &listener->proto_list);
proto_udp6.nb_listeners++;
}
/* Pause a listener. Returns < 0 in case of failure, 0 if the listener
* was totally stopped, or > 0 if correctly paused.
*/
int udp_pause_listener(struct listener *l)
{
/* we don't support pausing on UDP */
return -1;
}
/*
* Local variables:
* c-indent-level: 8
* c-basic-offset: 8
* End:
*/