// SPDX-License-Identifier: GPL-2.0-or-later
/*
* IPVS An implementation of the IP virtual server support for the
* LINUX operating system. IPVS is now implemented as a module
* over the Netfilter framework. IPVS can be used to build a
* high-performance and highly available server based on a
* cluster of servers.
*
* Authors: Wensong Zhang <[email protected]>
* Peter Kese <[email protected]>
* Julian Anastasov <[email protected]>
*
* The IPVS code for kernel 2.2 was done by Wensong Zhang and Peter Kese,
* with changes/fixes from Julian Anastasov, Lars Marowsky-Bree, Horms
* and others.
*
* Changes:
* Paul `Rusty' Russell properly handle non-linear skbs
* Harald Welte don't use nfcache
*/
#define KMSG_COMPONENT "IPVS"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/ip.h>
#include <linux/tcp.h>
#include <linux/sctp.h>
#include <linux/icmp.h>
#include <linux/slab.h>
#include <net/ip.h>
#include <net/tcp.h>
#include <net/udp.h>
#include <net/icmp.h> /* for icmp_send */
#include <net/gue.h>
#include <net/gre.h>
#include <net/route.h>
#include <net/ip6_checksum.h>
#include <net/netns/generic.h> /* net_generic() */
#include <linux/netfilter.h>
#include <linux/netfilter_ipv4.h>
#ifdef CONFIG_IP_VS_IPV6
#include <net/ipv6.h>
#include <linux/netfilter_ipv6.h>
#include <net/ip6_route.h>
#endif
#include <net/ip_vs.h>
#include <linux/indirect_call_wrapper.h>
EXPORT_SYMBOL(register_ip_vs_scheduler);
EXPORT_SYMBOL(unregister_ip_vs_scheduler);
EXPORT_SYMBOL(ip_vs_proto_name);
EXPORT_SYMBOL(ip_vs_conn_new);
EXPORT_SYMBOL(ip_vs_conn_in_get);
EXPORT_SYMBOL(ip_vs_conn_out_get);
#ifdef CONFIG_IP_VS_PROTO_TCP
EXPORT_SYMBOL(ip_vs_tcp_conn_listen);
#endif
EXPORT_SYMBOL(ip_vs_conn_put);
#ifdef CONFIG_IP_VS_DEBUG
EXPORT_SYMBOL(ip_vs_get_debug_level);
#endif
EXPORT_SYMBOL(ip_vs_new_conn_out);
#if defined(CONFIG_IP_VS_PROTO_TCP) && defined(CONFIG_IP_VS_PROTO_UDP)
#define SNAT_CALL(f, ...) \
INDIRECT_CALL_2(f, tcp_snat_handler, udp_snat_handler, __VA_ARGS__)
#elif defined(CONFIG_IP_VS_PROTO_TCP)
#define SNAT_CALL(f, ...) INDIRECT_CALL_1(f, tcp_snat_handler, __VA_ARGS__)
#elif defined(CONFIG_IP_VS_PROTO_UDP)
#define SNAT_CALL(f, ...) INDIRECT_CALL_1(f, udp_snat_handler, __VA_ARGS__)
#else
#define SNAT_CALL(f, ...) f(__VA_ARGS__)
#endif
static unsigned int ip_vs_net_id __read_mostly;
/* netns cnt used for uniqueness */
static atomic_t ipvs_netns_cnt = ATOMIC_INIT(0);
/* ID used in ICMP lookups */
#define icmp_id(icmph) (((icmph)->un).echo.id)
#define icmpv6_id(icmph) (icmph->icmp6_dataun.u_echo.identifier)
const char *ip_vs_proto_name(unsigned int proto)
{
static char buf[20];
switch (proto) {
case IPPROTO_IP:
return "IP";
case IPPROTO_UDP:
return "UDP";
case IPPROTO_TCP:
return "TCP";
case IPPROTO_SCTP:
return "SCTP";
case IPPROTO_ICMP:
return "ICMP";
#ifdef CONFIG_IP_VS_IPV6
case IPPROTO_ICMPV6:
return "ICMPv6";
#endif
default:
sprintf(buf, "IP_%u", proto);
return buf;
}
}
void ip_vs_init_hash_table(struct list_head *table, int rows)
{
while (--rows >= 0)
INIT_LIST_HEAD(&table[rows]);
}
static inline void
ip_vs_in_stats(struct ip_vs_conn *cp, struct sk_buff *skb)
{
struct ip_vs_dest *dest = cp->dest;
struct netns_ipvs *ipvs = cp->ipvs;
if (dest && (dest->flags & IP_VS_DEST_F_AVAILABLE)) {
struct ip_vs_cpu_stats *s;
struct ip_vs_service *svc;
local_bh_disable();
s = this_cpu_ptr(dest->stats.cpustats);
u64_stats_update_begin(&s->syncp);
u64_stats_inc(&s->cnt.inpkts);
u64_stats_add(&s->cnt.inbytes, skb->len);
u64_stats_update_end(&s->syncp);
svc = rcu_dereference(dest->svc);
s = this_cpu_ptr(svc->stats.cpustats);
u64_stats_update_begin(&s->syncp);
u64_stats_inc(&s->cnt.inpkts);
u64_stats_add(&s->cnt.inbytes, skb->len);
u64_stats_update_end(&s->syncp);
s = this_cpu_ptr(ipvs->tot_stats->s.cpustats);
u64_stats_update_begin(&s->syncp);
u64_stats_inc(&s->cnt.inpkts);
u64_stats_add(&s->cnt.inbytes, skb->len);
u64_stats_update_end(&s->syncp);
local_bh_enable();
}
}
static inline void
ip_vs_out_stats(struct ip_vs_conn *cp, struct sk_buff *skb)
{
struct ip_vs_dest *dest = cp->dest;
struct netns_ipvs *ipvs = cp->ipvs;
if (dest && (dest->flags & IP_VS_DEST_F_AVAILABLE)) {
struct ip_vs_cpu_stats *s;
struct ip_vs_service *svc;
local_bh_disable();
s = this_cpu_ptr(dest->stats.cpustats);
u64_stats_update_begin(&s->syncp);
u64_stats_inc(&s->cnt.outpkts);
u64_stats_add(&s->cnt.outbytes, skb->len);
u64_stats_update_end(&s->syncp);
svc = rcu_dereference(dest->svc);
s = this_cpu_ptr(svc->stats.cpustats);
u64_stats_update_begin(&s->syncp);
u64_stats_inc(&s->cnt.outpkts);
u64_stats_add(&s->cnt.outbytes, skb->len);
u64_stats_update_end(&s->syncp);
s = this_cpu_ptr(ipvs->tot_stats->s.cpustats);
u64_stats_update_begin(&s->syncp);
u64_stats_inc(&s->cnt.outpkts);
u64_stats_add(&s->cnt.outbytes, skb->len);
u64_stats_update_end(&s->syncp);
local_bh_enable();
}
}
static inline void
ip_vs_conn_stats(struct ip_vs_conn *cp, struct ip_vs_service *svc)
{
struct netns_ipvs *ipvs = svc->ipvs;
struct ip_vs_cpu_stats *s;
local_bh_disable();
s = this_cpu_ptr(cp->dest->stats.cpustats);
u64_stats_update_begin(&s->syncp);
u64_stats_inc(&s->cnt.conns);
u64_stats_update_end(&s->syncp);
s = this_cpu_ptr(svc->stats.cpustats);
u64_stats_update_begin(&s->syncp);
u64_stats_inc(&s->cnt.conns);
u64_stats_update_end(&s->syncp);
s = this_cpu_ptr(ipvs->tot_stats->s.cpustats);
u64_stats_update_begin(&s->syncp);
u64_stats_inc(&s->cnt.conns);
u64_stats_update_end(&s->syncp);
local_bh_enable();
}
static inline void
ip_vs_set_state(struct ip_vs_conn *cp, int direction,
const struct sk_buff *skb,
struct ip_vs_proto_data *pd)
{
if (likely(pd->pp->state_transition))
pd->pp->state_transition(cp, direction, skb, pd);
}
static inline int
ip_vs_conn_fill_param_persist(const struct ip_vs_service *svc,
struct sk_buff *skb, int protocol,
const union nf_inet_addr *caddr, __be16 cport,
const union nf_inet_addr *vaddr, __be16 vport,
struct ip_vs_conn_param *p)
{
ip_vs_conn_fill_param(svc->ipvs, svc->af, protocol, caddr, cport, vaddr,
vport, p);
p->pe = rcu_dereference(svc->pe);
if (p->pe && p->pe->fill_param)
return p->pe->fill_param(p, skb);
return 0;
}
/*
* IPVS persistent scheduling function
* It creates a connection entry according to its template if exists,
* or selects a server and creates a connection entry plus a template.
* Locking: we are svc user (svc->refcnt), so we hold all dests too
* Protocols supported: TCP, UDP
*/
static struct ip_vs_conn *
ip_vs_sched_persist(struct ip_vs_service *svc,
struct sk_buff *skb, __be16 src_port, __be16 dst_port,
int *ignored, struct ip_vs_iphdr *iph)
{
struct ip_vs_conn *cp = NULL;
struct ip_vs_dest *dest;
struct ip_vs_conn *ct;
__be16 dport = 0; /* destination port to forward */
unsigned int flags;
struct ip_vs_conn_param param;
const union nf_inet_addr fwmark = { .ip = htonl(svc->fwmark) };
union nf_inet_addr snet; /* source network of the client,
after masking */
const union nf_inet_addr *src_addr, *dst_addr;
if (likely(!ip_vs_iph_inverse(iph))) {
src_addr = &iph->saddr;
dst_addr = &iph->daddr;
} else {
src_addr = &iph->daddr;
dst_addr = &iph->saddr;
}
/* Mask saddr with the netmask to adjust template granularity */
#ifdef CONFIG_IP_VS_IPV6
if (svc->af == AF_INET6)
ipv6_addr_prefix(&snet.in6, &src_addr->in6,
(__force __u32) svc->netmask);
else
#endif
snet.ip = src_addr->ip & svc->netmask;
IP_VS_DBG_BUF(6, "p-schedule: src %s:%u dest %s:%u "
"mnet %s\n",
IP_VS_DBG_ADDR(svc->af, src_addr), ntohs(src_port),
IP_VS_DBG_ADDR(svc->af, dst_addr), ntohs(dst_port),
IP_VS_DBG_ADDR(svc->af, &snet));
/*
* As far as we know, FTP is a very complicated network protocol, and
* it uses control connection and data connections. For active FTP,
* FTP server initialize data connection to the client, its source port
* is often 20. For passive FTP, FTP server tells the clients the port
* that it passively listens to, and the client issues the data
* connection. In the tunneling or direct routing mode, the load
* balancer is on the client-to-server half of connection, the port
* number is unknown to the load balancer. So, a conn template like
* <caddr, 0, vaddr, 0, daddr, 0> is created for persistent FTP
* service, and a template like <caddr, 0, vaddr, vport, daddr, dport>
* is created for other persistent services.
*/
{
int protocol = iph->protocol;
const union nf_inet_addr *vaddr = dst_addr;
__be16 vport = 0;
if (dst_port == svc->port) {
/* non-FTP template:
* <protocol, caddr, 0, vaddr, vport, daddr, dport>
* FTP template:
* <protocol, caddr, 0, vaddr, 0, daddr, 0>
*/
if (svc->port != FTPPORT)
vport = dst_port;
} else {
/* Note: persistent fwmark-based services and
* persistent port zero service are handled here.
* fwmark template:
* <IPPROTO_IP,caddr,0,fwmark,0,daddr,0>
* port zero template:
* <protocol,caddr,0,vaddr,0,daddr,0>
*/
if (svc->fwmark) {
protocol = IPPROTO_IP;
vaddr = &fwmark;
}
}
/* return *ignored = -1 so NF_DROP can be used */
if (ip_vs_conn_fill_param_persist(svc, skb, protocol, &snet, 0,
vaddr, vport, ¶m) < 0) {
*ignored = -1;
return NULL;
}
}
/* Check if a template already exists */
ct = ip_vs_ct_in_get(¶m);
if (!ct || !ip_vs_check_template(ct, NULL)) {
struct ip_vs_scheduler *sched;
/*
* No template found or the dest of the connection
* template is not available.
* return *ignored=0 i.e. ICMP and NF_DROP
*/
sched = rcu_dereference(svc->scheduler);
if (sched) {
/* read svc->sched_data after svc->scheduler */
smp_rmb();
dest = sched->schedule(svc, skb, iph);
} else {
dest = NULL;
}
if (!dest) {
IP_VS_DBG(1, "p-schedule: no dest found.\n");
kfree(param.pe_data);
*ignored = 0;
return NULL;
}
if (dst_port == svc->port && svc->port != FTPPORT)
dport = dest->port;
/* Create a template
* This adds param.pe_data to the template,
* and thus param.pe_data will be destroyed
* when the template expires */
ct = ip_vs_conn_new(¶m, dest->af, &dest->addr, dport,
IP_VS_CONN_F_TEMPLATE, dest, skb->mark);
if (ct == NULL) {
kfree(param.pe_data);
*ignored = -1;
return NULL;
}
ct->timeout = svc->timeout;
} else {
/* set destination with the found template */
dest = ct->dest;
kfree(param.pe_data);
}
dport = dst_port;
if (dport == svc->port && dest->port)
dport = dest->port;
flags = (svc->flags & IP_VS_SVC_F_ONEPACKET
&& iph->protocol == IPPROTO_UDP) ?
IP_VS_CONN_F_ONE_PACKET : 0;
/*
* Create a new connection according to the template
*/
ip_vs_conn_fill_param(svc->ipvs, svc->af, iph->protocol, src_addr,
src_port, dst_addr, dst_port, ¶m);
cp = ip_vs_conn_new(¶m, dest->af, &dest->addr, dport, flags, dest,
skb->mark);
if (cp == NULL) {
ip_vs_conn_put(ct);
*ignored = -1;
return NULL;
}
/*
* Add its control
*/
ip_vs_control_add(cp, ct);
ip_vs_conn_put(ct);
ip_vs_conn_stats(cp, svc);
return cp;
}
/*
* IPVS main scheduling function
* It selects a server according to the virtual service, and
* creates a connection entry.
* Protocols supported: TCP, UDP
*
* Usage of *ignored
*
* 1 : protocol tried to schedule (eg. on SYN), found svc but the
* svc/scheduler decides that this packet should be accepted with
* NF_ACCEPT because it must not be scheduled.
*
* 0 : scheduler can not find destination, so try bypass or
* return ICMP and then NF_DROP (ip_vs_leave).
*
* -1 : scheduler tried to schedule but fatal error occurred, eg.
* ip_vs_conn_new failure (ENOMEM) or ip_vs_sip_fill_param
* failure such as missing Call-ID, ENOMEM on skb_linearize
* or pe_data. In this case we should return NF_DROP without
* any attempts to send ICMP with ip_vs_leave.
*/
struct ip_vs_conn *
ip_vs_schedule(struct ip_vs_service *svc, struct sk_buff *skb,
struct ip_vs_proto_data *pd, int *ignored,
struct ip_vs_iphdr *iph)
{
struct ip_vs_protocol *pp = pd->pp;
struct ip_vs_conn *cp = NULL;
struct ip_vs_scheduler *sched;
struct ip_vs_dest *dest;
__be16 _ports[2], *pptr, cport, vport;
const void *caddr, *vaddr;
unsigned int flags;
*ignored = 1;
/*
* IPv6 frags, only the first hit here.
*/
pptr = frag_safe_skb_hp(skb, iph->len, sizeof(_ports), _ports);
if (pptr == NULL)
return NULL;
if (likely(!ip_vs_iph_inverse(iph))) {
cport = pptr[0];
caddr = &iph->saddr;
vport = pptr[1];
vaddr = &iph->daddr;
} else {
cport = pptr[1];
caddr = &iph->daddr;
vport = pptr[0];
vaddr = &iph->saddr;
}
/*
* FTPDATA needs this check when using local real server.
* Never schedule Active FTPDATA connections from real server.
* For LVS-NAT they must be already created. For other methods
* with persistence the connection is created on SYN+ACK.
*/
if (cport == FTPDATA) {
IP_VS_DBG_PKT(12, svc->af, pp, skb, iph->off,
"Not scheduling FTPDATA");
return NULL;
}
/*
* Do not schedule replies from local real server.
*/
if ((!skb->dev || skb->dev->flags & IFF_LOOPBACK)) {
iph->hdr_flags ^= IP_VS_HDR_INVERSE;
cp = INDIRECT_CALL_1(pp->conn_in_get,
ip_vs_conn_in_get_proto, svc->ipvs,
svc->af, skb, iph);
iph->hdr_flags ^= IP_VS_HDR_INVERSE;
if (cp) {
IP_VS_DBG_PKT(12, svc->af, pp, skb, iph->off,
"Not scheduling reply for existing"
" connection");
__ip_vs_conn_put(cp);
return NULL;
}
}
/*
* Persistent service
*/
if (svc->flags & IP_VS_SVC_F_PERSISTENT)
return ip_vs_sched_persist(svc, skb, cport, vport, ignored,
iph);
*ignored = 0;
/*
* Non-persistent service
*/
if (!svc->fwmark && vport != svc->port) {
if (!svc->port)
pr_err("Schedule: port zero only supported "
"in persistent services, "
"check your ipvs configuration\n");
return NULL;
}
sched = rcu_dereference(svc->scheduler);
if (sched) {
/* read svc->sched_data after svc->scheduler */
smp_rmb();
dest = sched->schedule(svc, skb, iph);
} else {
dest = NULL;
}
if (dest == NULL) {
IP_VS_DBG(1, "Schedule: no dest found.\n");
return NULL;
}
flags = (svc->flags & IP_VS_SVC_F_ONEPACKET
&& iph->protocol == IPPROTO_UDP) ?
IP_VS_CONN_F_ONE_PACKET : 0;
/*
* Create a connection entry.
*/
{
struct ip_vs_conn_param p;
ip_vs_conn_fill_param(svc->ipvs, svc->af, iph->protocol,
caddr, cport, vaddr, vport, &p);
cp = ip_vs_conn_new(&p, dest->af, &dest->addr,
dest->port ? dest->port : vport,
flags, dest, skb->mark);
if (!cp) {
*ignored = -1;
return NULL;
}
}
IP_VS_DBG_BUF(6, "Schedule fwd:%c c:%s:%u v:%s:%u "
"d:%s:%u conn->flags:%X conn->refcnt:%d\n",
ip_vs_fwd_tag(cp),
IP_VS_DBG_ADDR(cp->af, &cp->caddr), ntohs(cp->cport),
IP_VS_DBG_ADDR(cp->af, &cp->vaddr), ntohs(cp->vport),
IP_VS_DBG_ADDR(cp->daf, &cp->daddr), ntohs(cp->dport),
cp->flags, refcount_read(&cp->refcnt));
ip_vs_conn_stats(cp, svc);
return cp;
}
static inline int ip_vs_addr_is_unicast(struct net *net, int af,
union nf_inet_addr *addr)
{
#ifdef CONFIG_IP_VS_IPV6
if (af == AF_INET6)
return ipv6_addr_type(&addr->in6) & IPV6_ADDR_UNICAST;
#endif
return (inet_addr_type(net, addr->ip) == RTN_UNICAST);
}
/*
* Pass or drop the packet.
* Called by ip_vs_in, when the virtual service is available but
* no destination is available for a new connection.
*/
int ip_vs_leave(struct ip_vs_service *svc, struct sk_buff *skb,
struct ip_vs_proto_data *pd, struct ip_vs_iphdr *iph)
{
__be16 _ports[2], *pptr, dport;
struct netns_ipvs *ipvs = svc->ipvs;
struct net *net = ipvs->net;
pptr = frag_safe_skb_hp(skb, iph->len, sizeof(_ports), _ports);
if (!pptr)
return NF_DROP;
dport = likely(!ip_vs_iph_inverse(iph)) ? pptr[1] : pptr[0];
/* if it is fwmark-based service, the cache_bypass sysctl is up
and the destination is a non-local unicast, then create
a cache_bypass connection entry */
if (sysctl_cache_bypass(ipvs) && svc->fwmark &&
!(iph->hdr_flags & (IP_VS_HDR_INVERSE | IP_VS_HDR_ICMP)) &&
ip_vs_addr_is_unicast(net, svc->af, &iph->daddr)) {
int ret;
struct ip_vs_conn *cp;
unsigned int flags = (svc->flags & IP_VS_SVC_F_ONEPACKET &&
iph->protocol == IPPROTO_UDP) ?
IP_VS_CONN_F_ONE_PACKET : 0;
union nf_inet_addr daddr = { .all = { 0, 0, 0, 0 } };
/* create a new connection entry */
IP_VS_DBG(6, "%s(): create a cache_bypass entry\n", __func__);
{
struct ip_vs_conn_param p;
ip_vs_conn_fill_param(svc->ipvs, svc->af, iph->protocol,
&iph->saddr, pptr[0],
&iph->daddr, pptr[1], &p);
cp = ip_vs_conn_new(&p, svc->af, &daddr, 0,
IP_VS_CONN_F_BYPASS | flags,
NULL, skb->mark);
if (!cp)
return NF_DROP;
}
/* statistics */
ip_vs_in_stats(cp, skb);
/* set state */
ip_vs_set_state(cp, IP_VS_DIR_INPUT, skb, pd);
/* transmit the first SYN packet */
ret = cp->packet_xmit(skb, cp, pd->pp, iph);
/* do not touch skb anymore */
if ((cp->flags & IP_VS_CONN_F_ONE_PACKET) && cp->control)
atomic_inc(&cp->control->in_pkts);
else
atomic_inc(&cp->in_pkts);
ip_vs_conn_put(cp);
return ret;
}
/*
* When the virtual ftp service is presented, packets destined
* for other services on the VIP may get here (except services
* listed in the ipvs table), pass the packets, because it is
* not ipvs job to decide to drop the packets.
*/
if (svc->port == FTPPORT && dport != FTPPORT)
return NF_ACCEPT;
if (unlikely(ip_vs_iph_icmp(iph)))
return NF_DROP;
/*
* Notify the client that the destination is unreachable, and
* release the socket buffer.
* Since it is in IP layer, the TCP socket is not actually
* created, the TCP RST packet cannot be sent, instead that
* ICMP_PORT_UNREACH is sent here no matter it is TCP/UDP. --WZ
*/
#ifdef CONFIG_IP_VS_IPV6
if (svc->af == AF_INET6) {
if (!skb->dev)
skb->dev = net->loopback_dev;
icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
} else
#endif
icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0);
return NF_DROP;
}
#ifdef CONFIG_SYSCTL
static int sysctl_snat_reroute(struct netns_ipvs *ipvs)
{
return ipvs->sysctl_snat_reroute;
}
static int sysctl_nat_icmp_send(struct netns_ipvs *ipvs)
{
return ipvs->sysctl_nat_icmp_send;
}
#else
static int sysctl_snat_reroute(struct netns_ipvs *ipvs) { return 0; }
static int sysctl_nat_icmp_send(struct netns_ipvs *ipvs) { return 0; }
#endif
__sum16 ip_vs_checksum_complete(struct sk_buff *skb, int offset)
{
return csum_fold(skb_checksum(skb, offset, skb->len - offset, 0));
}
static inline enum ip_defrag_users ip_vs_defrag_user(unsigned int hooknum)
{
if (NF_INET_LOCAL_IN == hooknum)
return IP_DEFRAG_VS_IN;
if (NF_INET_FORWARD == hooknum)
return IP_DEFRAG_VS_FWD;
return IP_DEFRAG_VS_OUT;
}
static inline int ip_vs_gather_frags(struct netns_ipvs *ipvs,
struct sk_buff *skb, u_int32_t user)
{
int err;
local_bh_disable();
err = ip_defrag(ipvs->net, skb, user);
local_bh_enable();
if (!err)
ip_send_check(ip_hdr(skb));
return err;
}
static int ip_vs_route_me_harder(struct netns_ipvs *ipvs, int af,
struct sk_buff *skb, unsigned int hooknum)
{
if (!sysctl_snat_reroute(ipvs))
return 0;
/* Reroute replies only to remote clients (FORWARD and LOCAL_OUT) */
if (NF_INET_LOCAL_IN == hooknum)
return 0;
#ifdef CONFIG_IP_VS_IPV6
if (af == AF_INET6) {
struct dst_entry *dst = skb_dst(skb);
if (dst->dev && !(dst->dev->flags & IFF_LOOPBACK) &&
ip6_route_me_harder(ipvs->net, skb->sk, skb) != 0)
return 1;
} else
#endif
if (!(skb_rtable(skb)->rt_flags & RTCF_LOCAL) &&
ip_route_me_harder(ipvs->net, skb->sk, skb, RTN_LOCAL) != 0)
return 1;
return 0;
}
/*
* Packet has been made sufficiently writable in caller
* - inout: 1=in->out, 0=out->in
*/
void ip_vs_nat_icmp(struct sk_buff *skb, struct ip_vs_protocol *pp,
struct ip_vs_conn *cp, int inout)
{
struct iphdr *iph = ip_hdr(skb);
unsigned int icmp_offset = iph->ihl*4;
struct icmphdr *icmph = (struct icmphdr *)(skb_network_header(skb) +
icmp_offset);
struct iphdr *ciph = (struct iphdr *)(icmph + 1);
if (inout) {
iph->saddr = cp->vaddr.ip;
ip_send_check(iph);
ciph->daddr = cp->vaddr.ip;
ip_send_check(ciph);
} else {
iph->daddr = cp->daddr.ip;
ip_send_check(iph);
ciph->saddr = cp->daddr.ip;
ip_send_check(ciph);
}
/* the TCP/UDP/SCTP port */
if (IPPROTO_TCP == ciph->protocol || IPPROTO_UDP == ciph->protocol ||
IPPROTO_SCTP == ciph->protocol) {
__be16 *ports = (void *)ciph + ciph->ihl*4;
if (inout)
ports[1] = cp->vport;
else
ports[0] = cp->dport;
}
/* And finally the ICMP checksum */
icmph->checksum = 0;
icmph->checksum = ip_vs_checksum_complete(skb, icmp_offset);
skb->ip_summed = CHECKSUM_UNNECESSARY;
if (inout)
IP_VS_DBG_PKT(11, AF_INET, pp, skb, (void *)ciph - (void *)iph,
"Forwarding altered outgoing ICMP");
else
IP_VS_DBG_PKT(11, AF_INET, pp, skb, (void *)ciph - (void *)iph,
"Forwarding altered incoming ICMP");
}
#ifdef CONFIG_IP_VS_IPV6
void ip_vs_nat_icmp_v6(struct sk_buff *skb, struct ip_vs_protocol *pp,
struct ip_vs_conn *cp, int inout)
{
struct ipv6hdr *iph = ipv6_hdr(skb);
unsigned int icmp_offset = 0;
unsigned int offs = 0; /* header offset*/
int protocol;
struct icmp6hdr *icmph;
struct ipv6hdr *ciph;
unsigned short fragoffs;
ipv6_find_hdr(skb, &icmp_offset, IPPROTO_ICMPV6, &fragoffs, NULL);
icmph = (struct icmp6hdr *)(skb_network_header(skb) + icmp_offset);
offs = icmp_offset + sizeof(struct icmp6hdr);
ciph = (struct ipv6hdr *)(skb_network_header(skb) + offs);
protocol = ipv6_find_hdr(skb, &offs, -1, &fragoffs, NULL);
if (inout) {
iph->saddr = cp->vaddr.in6;
ciph->daddr = cp->vaddr.in6;
} else {
iph->daddr = cp->daddr.in6;
ciph->saddr = cp->daddr.in6;
}
/* the TCP/UDP/SCTP port */
if (!fragoffs && (IPPROTO_TCP == protocol || IPPROTO_UDP == protocol ||
IPPROTO_SCTP == protocol)) {
__be16 *ports = (void *)(skb_network_header(skb) + offs);
IP_VS_DBG(11, "%s() changed port %d to %d\n", __func__,
ntohs(inout ? ports[1] : ports[0]),
ntohs(inout ? cp->vport : cp->dport));
if (inout)
ports[1] = cp->vport;
else
ports[0] = cp->dport;
}
/* And finally the ICMP checksum */
icmph->icmp6_cksum = ~csum_ipv6_magic(&iph->saddr, &iph->daddr,
skb->len - icmp_offset,
IPPROTO_ICMPV6, 0);
skb->csum_start = skb_network_header(skb) - skb->head + icmp_offset;
skb->csum_offset = offsetof(struct icmp6hdr, icmp6_cksum);
skb->ip_summed = CHECKSUM_PARTIAL;
if (inout)
IP_VS_DBG_PKT(11, AF_INET6, pp, skb,
(void *)ciph - (void *)iph,
"Forwarding altered outgoing ICMPv6");
else
IP_VS_DBG_PKT(11, AF_INET6, pp, skb,
(void *)ciph - (void *)iph,
"Forwarding altered incoming ICMPv6");
}
#endif
/* Handle relevant response ICMP messages - forward to the right
* destination host.
*/
static int handle_response_icmp(int af, struct sk_buff *skb,
union nf_inet_addr *snet,
__u8 protocol, struct ip_vs_conn *cp,
struct ip_vs_protocol *pp,
unsigned int offset, unsigned int ihl,
unsigned int hooknum)
{
unsigned int verdict = NF_DROP;
if (IP_VS_FWD_METHOD(cp) != IP_VS_CONN_F_MASQ)
goto after_nat;
/* Ensure the checksum is correct */
if (!skb_csum_unnecessary(skb) && ip_vs_checksum_complete(skb, ihl)) {
/* Failed checksum! */
IP_VS_DBG_BUF(1, "Forward ICMP: failed checksum from %s!\n",
IP_VS_DBG_ADDR(af, snet));
goto out;
}
if (IPPROTO_TCP == protocol || IPPROTO_UDP == protocol ||
IPPROTO_SCTP == protocol)
offset += 2 * sizeof(__u16);
if (skb_ensure_writable(skb, offset))
goto out;
#ifdef CONFIG_IP_VS_IPV6
if (af == AF_INET6)
ip_vs_nat_icmp_v6(skb, pp, cp, 1);
else
#endif
ip_vs_nat_icmp(skb, pp, cp, 1);
if (ip_vs_route_me_harder(cp->ipvs, af, skb, hooknum))
goto out;
after_nat:
/* do the statistics and put it back */
ip_vs_out_stats(cp, skb);
skb->ipvs_property = 1;
if (!(cp->flags & IP_VS_CONN_F_NFCT))
ip_vs_notrack(skb);
else
ip_vs_update_conntrack(skb, cp, 0);
verdict = NF_ACCEPT;
out:
__ip_vs_conn_put(cp);
return verdict;
}
/*
* Handle ICMP messages in the inside-to-outside direction (outgoing).
* Find any that might be relevant, check against existing connections.
* Currently handles error types - unreachable, quench, ttl exceeded.
*/
static int ip_vs_out_icmp(struct netns_ipvs *ipvs, struct sk_buff *skb,
int *related, unsigned int hooknum)
{
struct iphdr *iph;
struct icmphdr _icmph, *ic;
struct iphdr _ciph, *cih; /* The ip header contained within the ICMP */
struct ip_vs_iphdr ciph;
struct ip_vs_conn *cp;
struct ip_vs_protocol *pp;
unsigned int offset, ihl;
union nf_inet_addr snet;
*related = 1;
/* reassemble IP fragments */
if (ip_is_fragment(ip_hdr(skb))) {
if (ip_vs_gather_frags(ipvs, skb, ip_vs_defrag_user(hooknum)))
return NF_STOLEN;
}
iph = ip_hdr(skb);
offset = ihl = iph->ihl * 4;
ic = skb_header_pointer(skb, offset, sizeof(_icmph), &_icmph);
if (ic == NULL)
return NF_DROP;
IP_VS_DBG(12, "Outgoing ICMP (%d,%d) %pI4->%pI4\n",
ic->type, ntohs(icmp_id(ic)),
&iph->saddr, &iph->daddr);
/*
* Work through seeing if this is for us.
* These checks are supposed to be in an order that means easy
* things are checked first to speed up processing.... however
* this means that some packets will manage to get a long way
* down this stack and then be rejected, but that's life.
*/
if ((ic->type != ICMP_DEST_UNREACH) &&
(ic->type != ICMP_SOURCE_QUENCH) &&
(ic->type != ICMP_TIME_EXCEEDED)) {
*related = 0;
return NF_ACCEPT;
}
/* Now find the contained IP header */
offset += sizeof(_icmph);
cih = skb_header_pointer(skb, offset, sizeof(_ciph), &_ciph);
if (cih == NULL)
return NF_ACCEPT; /* The packet looks wrong, ignore */
pp = ip_vs_proto_get(cih->protocol);
if (!pp)
return NF_ACCEPT;
/* Is the embedded protocol header present? */
if (unlikely(cih->frag_off & htons(IP_OFFSET) &&
pp->dont_defrag))
return NF_ACCEPT;
IP_VS_DBG_PKT(11, AF_INET, pp, skb, offset,
"Checking outgoing ICMP for");
ip_vs_fill_iph_skb_icmp(AF_INET, skb, offset, true, &ciph);
/* The embedded headers contain source and dest in reverse order */
cp = INDIRECT_CALL_1(pp->conn_out_get, ip_vs_conn_out_get_proto,
ipvs, AF_INET, skb, &ciph);
if (!cp)
return NF_ACCEPT;
snet.ip = iph->saddr;
return handle_response_icmp(AF_INET, skb, &snet, cih->protocol, cp,
pp, ciph.len, ihl, hooknum);
}
#ifdef CONFIG_IP_VS_IPV6
static int ip_vs_out_icmp_v6(struct netns_ipvs *ipvs, struct sk_buff *skb,
int *related, unsigned int hooknum,
struct ip_vs_iphdr *ipvsh)
{
struct icmp6hdr _icmph, *ic;
struct ip_vs_iphdr ciph = {.flags = 0, .fragoffs = 0};/*Contained IP */
struct ip_vs_conn *cp;
struct ip_vs_protocol *pp;
union nf_inet_addr snet;
unsigned int offset;
*related = 1;
ic = frag_safe_skb_hp(skb, ipvsh->len, sizeof(_icmph), &_icmph);
if (ic == NULL)
return NF_DROP;
/*
* Work through seeing if this is for us.
* These checks are supposed to be in an order that means easy
* things are checked first to speed up processing.... however
* this means that some packets will manage to get a long way
* down this stack and then be rejected, but that's life.
*/
if (ic->icmp6_type & ICMPV6_INFOMSG_MASK) {
*related = 0;
return NF_ACCEPT;
}
/* Fragment header that is before ICMP header tells us that:
* it's not an error message since they can't be fragmented.
*/
if (ipvsh->flags & IP6_FH_F_FRAG)
return NF_DROP;
IP_VS_DBG(8, "Outgoing ICMPv6 (%d,%d) %pI6c->%pI6c\n",
ic->icmp6_type, ntohs(icmpv6_id(ic)),
&ipvsh->saddr, &ipvsh->daddr);
if (!ip_vs_fill_iph_skb_icmp(AF_INET6, skb, ipvsh->len + sizeof(_icmph),
true, &ciph))
return NF_ACCEPT; /* The packet looks wrong, ignore */
pp = ip_vs_proto_get(ciph.protocol);
if (!pp)
return NF_ACCEPT;
/* The embedded headers contain source and dest in reverse order */
cp = INDIRECT_CALL_1(pp->conn_out_get, ip_vs_conn_out_get_proto,
ipvs, AF_INET6, skb, &ciph);
if (!cp)
return NF_ACCEPT;
snet.in6 = ciph.saddr.in6;
offset = ciph.len;
return handle_response_icmp(AF_INET6, skb, &snet, ciph.protocol, cp,
pp, offset, sizeof(struct ipv6hdr),
hooknum);
}
#endif
/*
* Check if sctp chunc is ABORT chunk
*/
static inline int is_sctp_abort(const struct sk_buff *skb, int nh_len)
{
struct sctp_chunkhdr *sch, schunk;
sch = skb_header_pointer(skb, nh_len + sizeof(struct sctphdr),
sizeof(schunk), &schunk);
if (sch == NULL)
return 0;
if (sch->type == SCTP_CID_ABORT)
return 1;
return 0;
}
static inline int is_tcp_reset(const struct sk_buff *skb, int nh_len)
{
struct tcphdr _tcph, *th;
th = skb_header_pointer(skb, nh_len, sizeof(_tcph), &_tcph);
if (th == NULL)
return 0;
return th->rst;
}
static inline bool is_new_conn(const struct sk_buff *skb,
struct ip_vs_iphdr *iph)
{
switch (iph->protocol) {
case IPPROTO_TCP: {
struct tcphdr _tcph, *th;
th = skb_header_pointer(skb, iph->len, sizeof(_tcph), &_tcph);
if (th == NULL)
return false;
return th->syn;
}
case IPPROTO_SCTP: {
struct sctp_chunkhdr *sch, schunk;
sch = skb_header_pointer(skb, iph->len + sizeof(struct sctphdr),
sizeof(schunk), &schunk);
if (sch == NULL)
return false;
return sch->type == SCTP_CID_INIT;
}
default:
return false;
}
}
static inline bool is_new_conn_expected(const struct ip_vs_conn *cp,
int conn_reuse_mode)
{
/* Controlled (FTP DATA or persistence)? */
if (cp->control)
return false;
switch (cp->protocol) {
case IPPROTO_TCP:
return (cp->state == IP_VS_TCP_S_TIME_WAIT) ||
(cp->state == IP_VS_TCP_S_CLOSE) ||
((conn_reuse_mode & 2) &&
(cp->state == IP_VS_TCP_S_FIN_WAIT) &&
(cp->flags & IP_VS_CONN_F_NOOUTPUT));
case IPPROTO_SCTP:
return cp->state == IP_VS_SCTP_S_CLOSED;
default:
return false;
}
}
/* Generic function to create new connections for outgoing RS packets
*
* Pre-requisites for successful connection creation:
* 1) Virtual Service is NOT fwmark based:
* In fwmark-VS actual vaddr and vport are unknown to IPVS
* 2) Real Server and Virtual Service were NOT configured without port:
* This is to allow match of different VS to the same RS ip-addr
*/
struct ip_vs_conn *ip_vs_new_conn_out(struct ip_vs_service *svc,
struct ip_vs_dest *dest,
struct sk_buff *skb,
const struct ip_vs_iphdr *iph,
__be16 dport,
__be16 cport)
{
struct ip_vs_conn_param param;
struct ip_vs_conn *ct = NULL, *cp = NULL;
const union nf_inet_addr *vaddr, *daddr, *caddr;
union nf_inet_addr snet;
__be16 vport;
unsigned int flags;
vaddr = &svc->addr;
vport = svc->port;
daddr = &iph->saddr;
caddr = &iph->daddr;
/* check pre-requisites are satisfied */
if (svc->fwmark)
return NULL;
if (!vport || !dport)
return NULL;
/* for persistent service first create connection template */
if (svc->flags & IP_VS_SVC_F_PERSISTENT) {
/* apply netmask the same way ingress-side does */
#ifdef CONFIG_IP_VS_IPV6
if (svc->af == AF_INET6)
ipv6_addr_prefix(&snet.in6, &caddr->in6,
(__force __u32)svc->netmask);
else
#endif
snet.ip = caddr->ip & svc->netmask;
/* fill params and create template if not existent */
if (ip_vs_conn_fill_param_persist(svc, skb, iph->protocol,
&snet, 0, vaddr,
vport, ¶m) < 0)
return NULL;
ct = ip_vs_ct_in_get(¶m);
/* check if template exists and points to the same dest */
if (!ct || !ip_vs_check_template(ct, dest)) {
ct = ip_vs_conn_new(¶m, dest->af, daddr, dport,
IP_VS_CONN_F_TEMPLATE, dest, 0);
if (!ct) {
kfree(param.pe_data);
return NULL;
}
ct->timeout = svc->timeout;
} else {
kfree(param.pe_data);
}
}
/* connection flags */
flags = ((svc->flags & IP_VS_SVC_F_ONEPACKET) &&
iph->protocol == IPPROTO_UDP) ? IP_VS_CONN_F_ONE_PACKET : 0;
/* create connection */
ip_vs_conn_fill_param(svc->ipvs, svc->af, iph->protocol,
caddr, cport, vaddr, vport, ¶m);
cp = ip_vs_conn_new(¶m, dest->af, daddr, dport, flags, dest, 0);
if (!cp) {
if (ct)
ip_vs_conn_put(ct);
return NULL;
}
if (ct) {
ip_vs_control_add(cp, ct);
ip_vs_conn_put(ct);
}
ip_vs_conn_stats(cp, svc);
/* return connection (will be used to handle outgoing packet) */
IP_VS_DBG_BUF(6, "New connection RS-initiated:%c c:%s:%u v:%s:%u "
"d:%s:%u conn->flags:%X conn->refcnt:%d\n",
ip_vs_fwd_tag(cp),
IP_VS_DBG_ADDR(cp->af, &cp->caddr), ntohs(cp->cport),
IP_VS_DBG_ADDR(cp->af, &cp->vaddr), ntohs(cp->vport),
IP_VS_DBG_ADDR(cp->af, &cp->daddr), ntohs(cp->dport),
cp->flags, refcount_read(&cp->refcnt));
return cp;
}
/* Handle outgoing packets which are considered requests initiated by
* real servers, so that subsequent responses from external client can be
* routed to the right real server.
* Used also for outgoing responses in OPS mode.
*
* Connection management is handled by persistent-engine specific callback.
*/
static struct ip_vs_conn *__ip_vs_rs_conn_out(unsigned int hooknum,
struct netns_ipvs *ipvs,
int af, struct sk_buff *skb,
const struct ip_vs_iphdr *iph)
{
struct ip_vs_dest *dest;
struct ip_vs_conn *cp = NULL;
__be16 _ports[2], *pptr;
if (hooknum == NF_INET_LOCAL_IN)
return NULL;
pptr = frag_safe_skb_hp(skb, iph->len,
sizeof(_ports), _ports);
if (!pptr)
return NULL;
dest = ip_vs_find_real_service(ipvs, af, iph->protocol,
&iph->saddr, pptr[0]);
if (dest) {
struct ip_vs_service *svc;
struct ip_vs_pe *pe;
svc = rcu_dereference(dest->svc);
if (svc) {
pe = rcu_dereference(svc->pe);
if (pe && pe->conn_out)
cp = pe->conn_out(svc, dest, skb, iph,
pptr[0], pptr[1]);
}
}
return cp;
}
/* Handle response packets: rewrite addresses and send away...
*/
static unsigned int
handle_response(int af, struct sk_buff *skb, struct ip_vs_proto_data *pd,
struct ip_vs_conn *cp, struct ip_vs_iphdr *iph,
unsigned int hooknum)
{
struct ip_vs_protocol *pp = pd->pp;
if (IP_VS_FWD_METHOD(cp) != IP_VS_CONN_F_MASQ)
goto after_nat;
IP_VS_DBG_PKT(11, af, pp, skb, iph->off, "Outgoing packet");
if (skb_ensure_writable(skb, iph->len))
goto drop;
/* mangle the packet */
if (pp->snat_handler &&
!SNAT_CALL(pp->snat_handler, skb, pp, cp, iph))
goto drop;
#ifdef CONFIG_IP_VS_IPV6
if (af == AF_INET6)
ipv6_hdr(skb)->saddr = cp->vaddr.in6;
else
#endif
{
ip_hdr(skb)->saddr = cp->vaddr.ip;
ip_send_check(ip_hdr(skb));
}
/*
* nf_iterate does not expect change in the skb->dst->dev.
* It looks like it is not fatal to enable this code for hooks
* where our handlers are at the end of the chain list and
* when all next handlers use skb->dst->dev and not outdev.
* It will definitely route properly the inout NAT traffic
* when multiple paths are used.
*/
/* For policy routing, packets originating from this
* machine itself may be routed differently to packets
* passing through. We want this packet to be routed as
* if it came from this machine itself. So re-compute
* the routing information.
*/
if (ip_vs_route_me_harder(cp->ipvs, af, skb, hooknum))
goto drop;
IP_VS_DBG_PKT(10, af, pp, skb, iph->off, "After SNAT");
after_nat:
ip_vs_out_stats(cp, skb);
ip_vs_set_state(cp, IP_VS_DIR_OUTPUT, skb, pd);
skb->ipvs_property = 1;
if (!(cp->flags & IP_VS_CONN_F_NFCT))
ip_vs_notrack(skb);
else
ip_vs_update_conntrack(skb, cp, 0);
ip_vs_conn_put(cp);
return NF_ACCEPT;
drop:
ip_vs_conn_put(cp);
kfree_skb(skb);
return NF_STOLEN;
}
/*
* Check if outgoing packet belongs to the established ip_vs_conn.
*/
static unsigned int
ip_vs_out_hook(void *priv, struct sk_buff *skb, const struct nf_hook_state *state)
{
struct netns_ipvs *ipvs = net_ipvs(state->net);
unsigned int hooknum = state->hook;
struct ip_vs_iphdr iph;
struct ip_vs_protocol *pp;
struct ip_vs_proto_data *pd;
struct ip_vs_conn *cp;
int af = state->pf;
struct sock *sk;
/* Already marked as IPVS request or reply? */
if (skb->ipvs_property)
return NF_ACCEPT;
sk = skb_to_full_sk(skb);
/* Bad... Do not break raw sockets */
if (unlikely(sk && hooknum == NF_INET_LOCAL_OUT &&
af == AF_INET)) {
if (sk->sk_family == PF_INET && inet_test_bit(NODEFRAG, sk))
return NF_ACCEPT;
}
if (unlikely(!skb_dst(skb)))
return NF_ACCEPT;
if (!ipvs->enable)
return NF_ACCEPT;
ip_vs_fill_iph_skb(af, skb, false, &iph);
#ifdef CONFIG_IP_VS_IPV6
if (af == AF_INET6) {
if (unlikely(iph.protocol == IPPROTO_ICMPV6)) {
int related;
int verdict = ip_vs_out_icmp_v6(ipvs, skb, &related,
hooknum, &iph);
if (related)
return verdict;
}
} else
#endif
if (unlikely(iph.protocol == IPPROTO_ICMP)) {
int related;
int verdict = ip_vs_out_icmp(ipvs, skb, &related, hooknum);
if (related)
return verdict;
}
pd = ip_vs_proto_data_get(ipvs, iph.protocol);
if (unlikely(!pd))
return NF_ACCEPT;
pp = pd->pp;
/* reassemble IP fragments */
#ifdef CONFIG_IP_VS_IPV6
if (af == AF_INET)
#endif
if (unlikely(ip_is_fragment(ip_hdr(skb)) && !pp->dont_defrag)) {
if (ip_vs_gather_frags(ipvs, skb,
ip_vs_defrag_user(hooknum)))
return NF_STOLEN;
ip_vs_fill_iph_skb(AF_INET, skb, false, &iph);
}
/*
* Check if the packet belongs to an existing entry
*/
cp = INDIRECT_CALL_1(pp->conn_out_get, ip_vs_conn_out_get_proto,
ipvs, af, skb, &iph);
if (likely(cp))
return handle_response(af, skb, pd, cp, &iph, hooknum);
/* Check for real-server-started requests */
if (atomic_read(&ipvs->conn_out_counter)) {
/* Currently only for UDP:
* connection oriented protocols typically use
* ephemeral ports for outgoing connections, so
* related incoming responses would not match any VS
*/
if (pp->protocol == IPPROTO_UDP) {
cp = __ip_vs_rs_conn_out(hooknum, ipvs, af, skb, &iph);
if (likely(cp))
return handle_response(af, skb, pd, cp, &iph,
hooknum);
}
}
if (sysctl_nat_icmp_send(ipvs) &&
(pp->protocol == IPPROTO_TCP ||
pp->protocol == IPPROTO_UDP ||
pp->protocol == IPPROTO_SCTP)) {
__be16 _ports[2], *pptr;
pptr = frag_safe_skb_hp(skb, iph.len,
sizeof(_ports), _ports);
if (pptr == NULL)
return NF_ACCEPT; /* Not for me */
if (ip_vs_has_real_service(ipvs, af, iph.protocol, &iph.saddr,
pptr[0])) {
/*
* Notify the real server: there is no
* existing entry if it is not RST
* packet or not TCP packet.
*/
if ((iph.protocol != IPPROTO_TCP &&
iph.protocol != IPPROTO_SCTP)
|| ((iph.protocol == IPPROTO_TCP
&& !is_tcp_reset(skb, iph.len))
|| (iph.protocol == IPPROTO_SCTP
&& !is_sctp_abort(skb,
iph.len)))) {
#ifdef CONFIG_IP_VS_IPV6
if (af == AF_INET6) {
if (!skb->dev)
skb->dev = ipvs->net->loopback_dev;
icmpv6_send(skb,
ICMPV6_DEST_UNREACH,
ICMPV6_PORT_UNREACH,
0);
} else
#endif
icmp_send(skb,
ICMP_DEST_UNREACH,
ICMP_PORT_UNREACH, 0);
return NF_DROP;
}
}
}
IP_VS_DBG_PKT(12, af, pp, skb, iph.off,
"ip_vs_out: packet continues traversal as normal");
return NF_ACCEPT;
}
static unsigned int
ip_vs_try_to_schedule(struct netns_ipvs *ipvs, int af, struct sk_buff *skb,
struct ip_vs_proto_data *pd,
int *verdict, struct ip_vs_conn **cpp,
struct ip_vs_iphdr *iph)
{
struct ip_vs_protocol *pp = pd->pp;
if (!iph->fragoffs) {
/* No (second) fragments need to enter here, as nf_defrag_ipv6
* replayed fragment zero will already have created the cp
*/
/* Schedule and create new connection entry into cpp */
if (!pp->conn_schedule(ipvs, af, skb, pd, verdict, cpp, iph))
return 0;
}
if (unlikely(!*cpp)) {
/* sorry, all this trouble for a no-hit :) */
IP_VS_DBG_PKT(12, af, pp, skb, iph->off,
"ip_vs_in: packet continues traversal as normal");
/* Fragment couldn't be mapped to a conn entry */
if (iph->fragoffs)
IP_VS_DBG_PKT(7, af, pp, skb, iph->off,
"unhandled fragment");
*verdict = NF_ACCEPT;
return 0;
}
return 1;
}
/* Check the UDP tunnel and return its header length */
static int ipvs_udp_decap(struct netns_ipvs *ipvs, struct sk_buff *skb,
unsigned int offset, __u16 af,
const union nf_inet_addr *daddr, __u8 *proto)
{
struct udphdr _udph, *udph;
struct ip_vs_dest *dest;
udph = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
if (!udph)
goto unk;
offset += sizeof(struct udphdr);
dest = ip_vs_find_tunnel(ipvs, af, daddr, udph->dest);
if (!dest)
goto unk;
if (dest->tun_type == IP_VS_CONN_F_TUNNEL_TYPE_GUE) {
struct guehdr _gueh, *gueh;
gueh = skb_header_pointer(skb, offset, sizeof(_gueh), &_gueh);
if (!gueh)
goto unk;
if (gueh->control != 0 || gueh->version != 0)
goto unk;
/* Later we can support also IPPROTO_IPV6 */
if (gueh->proto_ctype != IPPROTO_IPIP)
goto unk;
*proto = gueh->proto_ctype;
return sizeof(struct udphdr) + sizeof(struct guehdr) +
(gueh->hlen << 2);
}
unk:
return 0;
}
/* Check the GRE tunnel and return its header length */
static int ipvs_gre_decap(struct netns_ipvs *ipvs, struct sk_buff *skb,
unsigned int offset, __u16 af,
const union nf_inet_addr *daddr, __u8 *proto)
{
struct gre_base_hdr _greh, *greh;
struct ip_vs_dest *dest;
greh = skb_header_pointer(skb, offset, sizeof(_greh), &_greh);
if (!greh)
goto unk;
dest = ip_vs_find_tunnel(ipvs, af, daddr, 0);
if (!dest)
goto unk;
if (dest->tun_type == IP_VS_CONN_F_TUNNEL_TYPE_GRE) {
IP_TUNNEL_DECLARE_FLAGS(flags);
__be16 type;
/* Only support version 0 and C (csum) */
if ((greh->flags & ~GRE_CSUM) != 0)
goto unk;
type = greh->protocol;
/* Later we can support also IPPROTO_IPV6 */
if (type != htons(ETH_P_IP))
goto unk;
*proto = IPPROTO_IPIP;
gre_flags_to_tnl_flags(flags, greh->flags);
return gre_calc_hlen(flags);
}
unk:
return 0;
}
/*
* Handle ICMP messages in the outside-to-inside direction (incoming).
* Find any that might be relevant, check against existing connections,
* forward to the right destination host if relevant.
* Currently handles error types - unreachable, quench, ttl exceeded.
*/
static int
ip_vs_in_icmp(struct netns_ipvs *ipvs, struct sk_buff *skb, int *related,
unsigned int hooknum)
{
struct iphdr *iph;
struct icmphdr _icmph, *ic;
struct iphdr _ciph, *cih; /* The ip header contained within the ICMP */
struct ip_vs_iphdr ciph;
struct ip_vs_conn *cp;
struct ip_vs_protocol *pp;
struct ip_vs_proto_data *pd;
unsigned int offset, offset2, ihl, verdict;
bool tunnel, new_cp = false;
union nf_inet_addr *raddr;
char *outer_proto = "IPIP";
*related = 1;
/* reassemble IP fragments */
if (ip_is_fragment(ip_hdr(skb))) {
if (ip_vs_gather_frags(ipvs, skb, ip_vs_defrag_user(hooknum)))
return NF_STOLEN;
}
iph = ip_hdr(skb);
offset = ihl = iph->ihl * 4;
ic = skb_header_pointer(skb, offset, sizeof(_icmph), &_icmph);
if (ic == NULL)
return NF_DROP;
IP_VS_DBG(12, "Incoming ICMP (%d,%d) %pI4->%pI4\n",
ic->type, ntohs(icmp_id(ic)),
&iph->saddr, &iph->daddr);
/*
* Work through seeing if this is for us.
* These checks are supposed to be in an order that means easy
* things are checked first to speed up processing.... however
* this means that some packets will manage to get a long way
* down this stack and then be rejected, but that's life.
*/
if ((ic->type != ICMP_DEST_UNREACH) &&
(ic->type != ICMP_SOURCE_QUENCH) &&
(ic->type != ICMP_TIME_EXCEEDED)) {
*related = 0;
return NF_ACCEPT;
}
/* Now find the contained IP header */
offset += sizeof(_icmph);
cih = skb_header_pointer(skb, offset, sizeof(_ciph), &_ciph);
if (cih == NULL)
return NF_ACCEPT; /* The packet looks wrong, ignore */
raddr = (union nf_inet_addr *)&cih->daddr;
/* Special case for errors for IPIP/UDP/GRE tunnel packets */
tunnel = false;
if (cih->protocol == IPPROTO_IPIP) {
struct ip_vs_dest *dest;
if (unlikely(cih->frag_off & htons(IP_OFFSET)))
return NF_ACCEPT;
/* Error for our IPIP must arrive at LOCAL_IN */
if (!(skb_rtable(skb)->rt_flags & RTCF_LOCAL))
return NF_ACCEPT;
dest = ip_vs_find_tunnel(ipvs, AF_INET, raddr, 0);
/* Only for known tunnel */
if (!dest || dest->tun_type != IP_VS_CONN_F_TUNNEL_TYPE_IPIP)
return NF_ACCEPT;
offset += cih->ihl * 4;
cih = skb_header_pointer(skb, offset, sizeof(_ciph), &_ciph);
if (cih == NULL)
return NF_ACCEPT; /* The packet looks wrong, ignore */
tunnel = true;
} else if ((cih->protocol == IPPROTO_UDP || /* Can be UDP encap */
cih->protocol == IPPROTO_GRE) && /* Can be GRE encap */
/* Error for our tunnel must arrive at LOCAL_IN */
(skb_rtable(skb)->rt_flags & RTCF_LOCAL)) {
__u8 iproto;
int ulen;
/* Non-first fragment has no UDP/GRE header */
if (unlikely(cih->frag_off & htons(IP_OFFSET)))
return NF_ACCEPT;
offset2 = offset + cih->ihl * 4;
if (cih->protocol == IPPROTO_UDP) {
ulen = ipvs_udp_decap(ipvs, skb, offset2, AF_INET,
raddr, &iproto);
outer_proto = "UDP";
} else {
ulen = ipvs_gre_decap(ipvs, skb, offset2, AF_INET,
raddr, &iproto);
outer_proto = "GRE";
}
if (ulen > 0) {
/* Skip IP and UDP/GRE tunnel headers */
offset = offset2 + ulen;
/* Now we should be at the original IP header */
cih = skb_header_pointer(skb, offset, sizeof(_ciph),
&_ciph);
if (cih && cih->version == 4 && cih->ihl >= 5 &&
iproto == IPPROTO_IPIP)
tunnel = true;
else
return NF_ACCEPT;
}
}
pd = ip_vs_proto_data_get(ipvs, cih->protocol);
if (!pd)
return NF_ACCEPT;
pp = pd->pp;
/* Is the embedded protocol header present? */
if (unlikely(cih->frag_off & htons(IP_OFFSET) &&
pp->dont_defrag))
return NF_ACCEPT;
IP_VS_DBG_PKT(11, AF_INET, pp, skb, offset,
"Checking incoming ICMP for");
offset2 = offset;
ip_vs_fill_iph_skb_icmp(AF_INET, skb, offset, !tunnel, &ciph);
offset = ciph.len;
/* The embedded headers contain source and dest in reverse order.
* For IPIP/UDP/GRE tunnel this is error for request, not for reply.
*/
cp = INDIRECT_CALL_1(pp->conn_in_get, ip_vs_conn_in_get_proto,
ipvs, AF_INET, skb, &ciph);
if (!cp) {
int v;
if (tunnel || !sysctl_schedule_icmp(ipvs))
return NF_ACCEPT;
if (!ip_vs_try_to_schedule(ipvs, AF_INET, skb, pd, &v, &cp, &ciph))
return v;
new_cp = true;
}
verdict = NF_DROP;
/* Ensure the checksum is correct */
if (!skb_csum_unnecessary(skb) && ip_vs_checksum_complete(skb, ihl)) {
/* Failed checksum! */
IP_VS_DBG(1, "Incoming ICMP: failed checksum from %pI4!\n",
&iph->saddr);
goto out;
}
if (tunnel) {
__be32 info = ic->un.gateway;
__u8 type = ic->type;
__u8 code = ic->code;
/* Update the MTU */
if (ic->type == ICMP_DEST_UNREACH &&
ic->code == ICMP_FRAG_NEEDED) {
struct ip_vs_dest *dest = cp->dest;
u32 mtu = ntohs(ic->un.frag.mtu);
__be16 frag_off = cih->frag_off;
/* Strip outer IP and ICMP, go to IPIP/UDP/GRE header */
if (pskb_pull(skb, ihl + sizeof(_icmph)) == NULL)
goto ignore_tunnel;
offset2 -= ihl + sizeof(_icmph);
skb_reset_network_header(skb);
IP_VS_DBG(12, "ICMP for %s %pI4->%pI4: mtu=%u\n",
outer_proto, &ip_hdr(skb)->saddr,
&ip_hdr(skb)->daddr, mtu);
ipv4_update_pmtu(skb, ipvs->net, mtu, 0, 0);
/* Client uses PMTUD? */
if (!(frag_off & htons(IP_DF)))
goto ignore_tunnel;
/* Prefer the resulting PMTU */
if (dest) {
struct ip_vs_dest_dst *dest_dst;
dest_dst = rcu_dereference(dest->dest_dst);
if (dest_dst)
mtu = dst_mtu(dest_dst->dst_cache);
}
if (mtu > 68 + sizeof(struct iphdr))
mtu -= sizeof(struct iphdr);
info = htonl(mtu);
}
/* Strip outer IP, ICMP and IPIP/UDP/GRE, go to IP header of
* original request.
*/
if (pskb_pull(skb, offset2) == NULL)
goto ignore_tunnel;
skb_reset_network_header(skb);
IP_VS_DBG(12, "Sending ICMP for %pI4->%pI4: t=%u, c=%u, i=%u\n",
&ip_hdr(skb)->saddr, &ip_hdr(skb)->daddr,
type, code, ntohl(info));
icmp_send(skb, type, code, info);
/* ICMP can be shorter but anyways, account it */
ip_vs_out_stats(cp, skb);
ignore_tunnel:
consume_skb(skb);
verdict = NF_STOLEN;
goto out;
}
/* do the statistics and put it back */
ip_vs_in_stats(cp, skb);
if (IPPROTO_TCP == cih->protocol || IPPROTO_UDP == cih->protocol ||
IPPROTO_SCTP == cih->protocol)
offset += 2 * sizeof(__u16);
verdict = ip_vs_icmp_xmit(skb, cp, pp, offset, hooknum, &ciph);
out:
if (likely(!new_cp))
__ip_vs_conn_put(cp);
else
ip_vs_conn_put(cp);
return verdict;
}
#ifdef CONFIG_IP_VS_IPV6
static int ip_vs_in_icmp_v6(struct netns_ipvs *ipvs, struct sk_buff *skb,
int *related, unsigned int hooknum,
struct ip_vs_iphdr *iph)
{
struct icmp6hdr _icmph, *ic;
struct ip_vs_iphdr ciph = {.flags = 0, .fragoffs = 0};/*Contained IP */
struct ip_vs_conn *cp;
struct ip_vs_protocol *pp;
struct ip_vs_proto_data *pd;
unsigned int offset, verdict;
bool new_cp = false;
*related = 1;
ic = frag_safe_skb_hp(skb, iph->len, sizeof(_icmph), &_icmph);
if (ic == NULL)
return NF_DROP;
/*
* Work through seeing if this is for us.
* These checks are supposed to be in an order that means easy
* things are checked first to speed up processing.... however
* this means that some packets will manage to get a long way
* down this stack and then be rejected, but that's life.
*/
if (ic->icmp6_type & ICMPV6_INFOMSG_MASK) {
*related = 0;
return NF_ACCEPT;
}
/* Fragment header that is before ICMP header tells us that:
* it's not an error message since they can't be fragmented.
*/
if (iph->flags & IP6_FH_F_FRAG)
return NF_DROP;
IP_VS_DBG(8, "Incoming ICMPv6 (%d,%d) %pI6c->%pI6c\n",
ic->icmp6_type, ntohs(icmpv6_id(ic)),
&iph->saddr, &iph->daddr);
offset = iph->len + sizeof(_icmph);
if (!ip_vs_fill_iph_skb_icmp(AF_INET6, skb, offset, true, &ciph))
return NF_ACCEPT;
pd = ip_vs_proto_data_get(ipvs, ciph.protocol);
if (!pd)
return NF_ACCEPT;
pp = pd->pp;
/* Cannot handle fragmented embedded protocol */
if (ciph.fragoffs)
return NF_ACCEPT;
IP_VS_DBG_PKT(11, AF_INET6, pp, skb, offset,
"Checking incoming ICMPv6 for");
/* The embedded headers contain source and dest in reverse order
* if not from localhost
*/
cp = INDIRECT_CALL_1(pp->conn_in_get, ip_vs_conn_in_get_proto,
ipvs, AF_INET6, skb, &ciph);
if (!cp) {
int v;
if (!sysctl_schedule_icmp(ipvs))
return NF_ACCEPT;
if (!ip_vs_try_to_schedule(ipvs, AF_INET6, skb, pd, &v, &cp, &ciph))
return v;
new_cp = true;
}
/* VS/TUN, VS/DR and LOCALNODE just let it go */
if ((hooknum == NF_INET_LOCAL_OUT) &&
(IP_VS_FWD_METHOD(cp) != IP_VS_CONN_F_MASQ)) {
verdict = NF_ACCEPT;
goto out;
}
/* do the statistics and put it back */
ip_vs_in_stats(cp, skb);
/* Need to mangle contained IPv6 header in ICMPv6 packet */
offset = ciph.len;
if (IPPROTO_TCP == ciph.protocol || IPPROTO_UDP == ciph.protocol ||
IPPROTO_SCTP == ciph.protocol)
offset += 2 * sizeof(__u16); /* Also mangle ports */
verdict = ip_vs_icmp_xmit_v6(skb, cp, pp, offset, hooknum, &ciph);
out:
if (likely(!new_cp))
__ip_vs_conn_put(cp);
else
ip_vs_conn_put(cp);
return verdict;
}
#endif
/*
* Check if it's for virtual services, look it up,
* and send it on its way...
*/
static unsigned int
ip_vs_in_hook(void *priv, struct sk_buff *skb, const struct nf_hook_state *state)
{
struct netns_ipvs *ipvs = net_ipvs(state->net);
unsigned int hooknum = state->hook;
struct ip_vs_iphdr iph;
struct ip_vs_protocol *pp;
struct ip_vs_proto_data *pd;
struct ip_vs_conn *cp;
int ret, pkts;
struct sock *sk;
int af = state->pf;
/* Already marked as IPVS request or reply? */
if (skb->ipvs_property)
return NF_ACCEPT;
/*
* Big tappo:
* - remote client: only PACKET_HOST
* - route: used for struct net when skb->dev is unset
*/
if (unlikely((skb->pkt_type != PACKET_HOST &&
hooknum != NF_INET_LOCAL_OUT) ||
!skb_dst(skb))) {
ip_vs_fill_iph_skb(af, skb, false, &iph);
IP_VS_DBG_BUF(12, "packet type=%d proto=%d daddr=%s"
" ignored in hook %u\n",
skb->pkt_type, iph.protocol,
IP_VS_DBG_ADDR(af, &iph.daddr), hooknum);
return NF_ACCEPT;
}
/* ipvs enabled in this netns ? */
if (unlikely(sysctl_backup_only(ipvs) || !ipvs->enable))
return NF_ACCEPT;
ip_vs_fill_iph_skb(af, skb, false, &iph);
/* Bad... Do not break raw sockets */
sk = skb_to_full_sk(skb);
if (unlikely(sk && hooknum == NF_INET_LOCAL_OUT &&
af == AF_INET)) {
if (sk->sk_family == PF_INET && inet_test_bit(NODEFRAG, sk))
return NF_ACCEPT;
}
#ifdef CONFIG_IP_VS_IPV6
if (af == AF_INET6) {
if (unlikely(iph.protocol == IPPROTO_ICMPV6)) {
int related;
int verdict = ip_vs_in_icmp_v6(ipvs, skb, &related,
hooknum, &iph);
if (related)
return verdict;
}
} else
#endif
if (unlikely(iph.protocol == IPPROTO_ICMP)) {
int related;
int verdict = ip_vs_in_icmp(ipvs, skb, &related,
hooknum);
if (related)
return verdict;
}
/* Protocol supported? */
pd = ip_vs_proto_data_get(ipvs, iph.protocol);
if (unlikely(!pd)) {
/* The only way we'll see this packet again is if it's
* encapsulated, so mark it with ipvs_property=1 so we
* skip it if we're ignoring tunneled packets
*/
if (sysctl_ignore_tunneled(ipvs))
skb->ipvs_property = 1;
return NF_ACCEPT;
}
pp = pd->pp;
/*
* Check if the packet belongs to an existing connection entry
*/
cp = INDIRECT_CALL_1(pp->conn_in_get, ip_vs_conn_in_get_proto,
ipvs, af, skb, &iph);
if (!iph.fragoffs && is_new_conn(skb, &iph) && cp) {
int conn_reuse_mode = sysctl_conn_reuse_mode(ipvs);
bool old_ct = false, resched = false;
if (unlikely(sysctl_expire_nodest_conn(ipvs)) && cp->dest &&
unlikely(!atomic_read(&cp->dest->weight))) {
resched = true;
old_ct = ip_vs_conn_uses_old_conntrack(cp, skb);
} else if (conn_reuse_mode &&
is_new_conn_expected(cp, conn_reuse_mode)) {
old_ct = ip_vs_conn_uses_old_conntrack(cp, skb);
if (!atomic_read(&cp->n_control)) {
resched = true;
} else {
/* Do not reschedule controlling connection
* that uses conntrack while it is still
* referenced by controlled connection(s).
*/
resched = !old_ct;
}
}
if (resched) {
if (!old_ct)
cp->flags &= ~IP_VS_CONN_F_NFCT;
if (!atomic_read(&cp->n_control))
ip_vs_conn_expire_now(cp);
__ip_vs_conn_put(cp);
if (old_ct)
return NF_DROP;
cp = NULL;
}
}
/* Check the server status */
if (cp && cp->dest && !(cp->dest->flags & IP_VS_DEST_F_AVAILABLE)) {
/* the destination server is not available */
if (sysctl_expire_nodest_conn(ipvs)) {
bool old_ct = ip_vs_conn_uses_old_conntrack(cp, skb);
if (!old_ct)
cp->flags &= ~IP_VS_CONN_F_NFCT;
ip_vs_conn_expire_now(cp);
__ip_vs_conn_put(cp);
if (old_ct)
return NF_DROP;
cp = NULL;
} else {
__ip_vs_conn_put(cp);
return NF_DROP;
}
}
if (unlikely(!cp)) {
int v;
if (!ip_vs_try_to_schedule(ipvs, af, skb, pd, &v, &cp, &iph))
return v;
}
IP_VS_DBG_PKT(11, af, pp, skb, iph.off, "Incoming packet");
ip_vs_in_stats(cp, skb);
ip_vs_set_state(cp, IP_VS_DIR_INPUT, skb, pd);
if (cp->packet_xmit)
ret = cp->packet_xmit(skb, cp, pp, &iph);
/* do not touch skb anymore */
else {
IP_VS_DBG_RL("warning: packet_xmit is null");
ret = NF_ACCEPT;
}
/* Increase its packet counter and check if it is needed
* to be synchronized
*
* Sync connection if it is about to close to
* encorage the standby servers to update the connections timeout
*
* For ONE_PKT let ip_vs_sync_conn() do the filter work.
*/
if (cp->flags & IP_VS_CONN_F_ONE_PACKET)
pkts = sysctl_sync_threshold(ipvs);
else
pkts = atomic_inc_return(&cp->in_pkts);
if (ipvs->sync_state & IP_VS_STATE_MASTER)
ip_vs_sync_conn(ipvs, cp, pkts);
else if ((cp->flags & IP_VS_CONN_F_ONE_PACKET) && cp->control)
/* increment is done inside ip_vs_sync_conn too */
atomic_inc(&cp->control->in_pkts);
ip_vs_conn_put(cp);
return ret;
}
/*
* It is hooked at the NF_INET_FORWARD chain, in order to catch ICMP
* related packets destined for 0.0.0.0/0.
* When fwmark-based virtual service is used, such as transparent
* cache cluster, TCP packets can be marked and routed to ip_vs_in,
* but ICMP destined for 0.0.0.0/0 cannot not be easily marked and
* sent to ip_vs_in_icmp. So, catch them at the NF_INET_FORWARD chain
* and send them to ip_vs_in_icmp.
*/
static unsigned int
ip_vs_forward_icmp(void *priv, struct sk_buff *skb,
const struct nf_hook_state *state)
{
struct netns_ipvs *ipvs = net_ipvs(state->net);
int r;
/* ipvs enabled in this netns ? */
if (unlikely(sysctl_backup_only(ipvs) || !ipvs->enable))
return NF_ACCEPT;
if (state->pf == NFPROTO_IPV4) {
if (ip_hdr(skb)->protocol != IPPROTO_ICMP)
return NF_ACCEPT;
#ifdef CONFIG_IP_VS_IPV6
} else {
struct ip_vs_iphdr iphdr;
ip_vs_fill_iph_skb(AF_INET6, skb, false, &iphdr);
if (iphdr.protocol != IPPROTO_ICMPV6)
return NF_ACCEPT;
return ip_vs_in_icmp_v6(ipvs, skb, &r, state->hook, &iphdr);
#endif
}
return ip_vs_in_icmp(ipvs, skb, &r, state->hook);
}
static const struct nf_hook_ops ip_vs_ops4[] = {
/* After packet filtering, change source only for VS/NAT */
{
.hook = ip_vs_out_hook,
.pf = NFPROTO_IPV4,
.hooknum = NF_INET_LOCAL_IN,
.priority = NF_IP_PRI_NAT_SRC - 2,
},
/* After packet filtering, forward packet through VS/DR, VS/TUN,
* or VS/NAT(change destination), so that filtering rules can be
* applied to IPVS. */
{
.hook = ip_vs_in_hook,
.pf = NFPROTO_IPV4,
.hooknum = NF_INET_LOCAL_IN,
.priority = NF_IP_PRI_NAT_SRC - 1,
},
/* Before ip_vs_in, change source only for VS/NAT */
{
.hook = ip_vs_out_hook,
.pf = NFPROTO_IPV4,
.hooknum = NF_INET_LOCAL_OUT,
.priority = NF_IP_PRI_NAT_DST + 1,
},
/* After mangle, schedule and forward local requests */
{
.hook = ip_vs_in_hook,
.pf = NFPROTO_IPV4,
.hooknum = NF_INET_LOCAL_OUT,
.priority = NF_IP_PRI_NAT_DST + 2,
},
/* After packet filtering (but before ip_vs_out_icmp), catch icmp
* destined for 0.0.0.0/0, which is for incoming IPVS connections */
{
.hook = ip_vs_forward_icmp,
.pf = NFPROTO_IPV4,
.hooknum = NF_INET_FORWARD,
.priority = 99,
},
/* After packet filtering, change source only for VS/NAT */
{
.hook = ip_vs_out_hook,
.pf = NFPROTO_IPV4,
.hooknum = NF_INET_FORWARD,
.priority = 100,
},
};
#ifdef CONFIG_IP_VS_IPV6
static const struct nf_hook_ops ip_vs_ops6[] = {
/* After packet filtering, change source only for VS/NAT */
{
.hook = ip_vs_out_hook,
.pf = NFPROTO_IPV6,
.hooknum = NF_INET_LOCAL_IN,
.priority = NF_IP6_PRI_NAT_SRC - 2,
},
/* After packet filtering, forward packet through VS/DR, VS/TUN,
* or VS/NAT(change destination), so that filtering rules can be
* applied to IPVS. */
{
.hook = ip_vs_in_hook,
.pf = NFPROTO_IPV6,
.hooknum = NF_INET_LOCAL_IN,
.priority = NF_IP6_PRI_NAT_SRC - 1,
},
/* Before ip_vs_in, change source only for VS/NAT */
{
.hook = ip_vs_out_hook,
.pf = NFPROTO_IPV6,
.hooknum = NF_INET_LOCAL_OUT,
.priority = NF_IP6_PRI_NAT_DST + 1,
},
/* After mangle, schedule and forward local requests */
{
.hook = ip_vs_in_hook,
.pf = NFPROTO_IPV6,
.hooknum = NF_INET_LOCAL_OUT,
.priority = NF_IP6_PRI_NAT_DST + 2,
},
/* After packet filtering (but before ip_vs_out_icmp), catch icmp
* destined for 0.0.0.0/0, which is for incoming IPVS connections */
{
.hook = ip_vs_forward_icmp,
.pf = NFPROTO_IPV6,
.hooknum = NF_INET_FORWARD,
.priority = 99,
},
/* After packet filtering, change source only for VS/NAT */
{
.hook = ip_vs_out_hook,
.pf = NFPROTO_IPV6,
.hooknum = NF_INET_FORWARD,
.priority = 100,
},
};
#endif
int ip_vs_register_hooks(struct netns_ipvs *ipvs, unsigned int af)
{
const struct nf_hook_ops *ops;
unsigned int count;
unsigned int afmask;
int ret = 0;
if (af == AF_INET6) {
#ifdef CONFIG_IP_VS_IPV6
ops = ip_vs_ops6;
count = ARRAY_SIZE(ip_vs_ops6);
afmask = 2;
#else
return -EINVAL;
#endif
} else {
ops = ip_vs_ops4;
count = ARRAY_SIZE(ip_vs_ops4);
afmask = 1;
}
if (!(ipvs->hooks_afmask & afmask)) {
ret = nf_register_net_hooks(ipvs->net, ops, count);
if (ret >= 0)
ipvs->hooks_afmask |= afmask;
}
return ret;
}
void ip_vs_unregister_hooks(struct netns_ipvs *ipvs, unsigned int af)
{
const struct nf_hook_ops *ops;
unsigned int count;
unsigned int afmask;
if (af == AF_INET6) {
#ifdef CONFIG_IP_VS_IPV6
ops = ip_vs_ops6;
count = ARRAY_SIZE(ip_vs_ops6);
afmask = 2;
#else
return;
#endif
} else {
ops = ip_vs_ops4;
count = ARRAY_SIZE(ip_vs_ops4);
afmask = 1;
}
if (ipvs->hooks_afmask & afmask) {
nf_unregister_net_hooks(ipvs->net, ops, count);
ipvs->hooks_afmask &= ~afmask;
}
}
/*
* Initialize IP Virtual Server netns mem.
*/
static int __net_init __ip_vs_init(struct net *net)
{
struct netns_ipvs *ipvs;
ipvs = net_generic(net, ip_vs_net_id);
if (ipvs == NULL)
return -ENOMEM;
/* Hold the beast until a service is registered */
ipvs->enable = 0;
ipvs->net = net;
/* Counters used for creating unique names */
ipvs->gen = atomic_read(&ipvs_netns_cnt);
atomic_inc(&ipvs_netns_cnt);
net->ipvs = ipvs;
if (ip_vs_estimator_net_init(ipvs) < 0)
goto estimator_fail;
if (ip_vs_control_net_init(ipvs) < 0)
goto control_fail;
if (ip_vs_protocol_net_init(ipvs) < 0)
goto protocol_fail;
if (ip_vs_app_net_init(ipvs) < 0)
goto app_fail;
if (ip_vs_conn_net_init(ipvs) < 0)
goto conn_fail;
if (ip_vs_sync_net_init(ipvs) < 0)
goto sync_fail;
return 0;
/*
* Error handling
*/
sync_fail:
ip_vs_conn_net_cleanup(ipvs);
conn_fail:
ip_vs_app_net_cleanup(ipvs);
app_fail:
ip_vs_protocol_net_cleanup(ipvs);
protocol_fail:
ip_vs_control_net_cleanup(ipvs);
control_fail:
ip_vs_estimator_net_cleanup(ipvs);
estimator_fail:
net->ipvs = NULL;
return -ENOMEM;
}
static void __net_exit __ip_vs_cleanup_batch(struct list_head *net_list)
{
struct netns_ipvs *ipvs;
struct net *net;
ip_vs_service_nets_cleanup(net_list); /* ip_vs_flush() with locks */
list_for_each_entry(net, net_list, exit_list) {
ipvs = net_ipvs(net);
ip_vs_conn_net_cleanup(ipvs);
ip_vs_app_net_cleanup(ipvs);
ip_vs_protocol_net_cleanup(ipvs);
ip_vs_control_net_cleanup(ipvs);
ip_vs_estimator_net_cleanup(ipvs);
IP_VS_DBG(2, "ipvs netns %d released\n", ipvs->gen);
net->ipvs = NULL;
}
}
static void __net_exit __ip_vs_dev_cleanup_batch(struct list_head *net_list)
{
struct netns_ipvs *ipvs;
struct net *net;
list_for_each_entry(net, net_list, exit_list) {
ipvs = net_ipvs(net);
ip_vs_unregister_hooks(ipvs, AF_INET);
ip_vs_unregister_hooks(ipvs, AF_INET6);
ipvs->enable = 0; /* Disable packet reception */
smp_wmb();
ip_vs_sync_net_cleanup(ipvs);
}
}
static struct pernet_operations ipvs_core_ops = {
.init = __ip_vs_init,
.exit_batch = __ip_vs_cleanup_batch,
.id = &ip_vs_net_id,
.size = sizeof(struct netns_ipvs),
};
static struct pernet_operations ipvs_core_dev_ops = {
.exit_batch = __ip_vs_dev_cleanup_batch,
};
/*
* Initialize IP Virtual Server
*/
static int __init ip_vs_init(void)
{
int ret;
ret = ip_vs_control_init();
if (ret < 0) {
pr_err("can't setup control.\n");
goto exit;
}
ip_vs_protocol_init();
ret = ip_vs_conn_init();
if (ret < 0) {
pr_err("can't setup connection table.\n");
goto cleanup_protocol;
}
ret = register_pernet_subsys(&ipvs_core_ops); /* Alloc ip_vs struct */
if (ret < 0)
goto cleanup_conn;
ret = register_pernet_device(&ipvs_core_dev_ops);
if (ret < 0)
goto cleanup_sub;
ret = ip_vs_register_nl_ioctl();
if (ret < 0) {
pr_err("can't register netlink/ioctl.\n");
goto cleanup_dev;
}
pr_info("ipvs loaded.\n");
return ret;
cleanup_dev:
unregister_pernet_device(&ipvs_core_dev_ops);
cleanup_sub:
unregister_pernet_subsys(&ipvs_core_ops);
cleanup_conn:
ip_vs_conn_cleanup();
cleanup_protocol:
ip_vs_protocol_cleanup();
ip_vs_control_cleanup();
exit:
return ret;
}
static void __exit ip_vs_cleanup(void)
{
ip_vs_unregister_nl_ioctl();
unregister_pernet_device(&ipvs_core_dev_ops);
unregister_pernet_subsys(&ipvs_core_ops); /* free ip_vs struct */
ip_vs_conn_cleanup();
ip_vs_protocol_cleanup();
ip_vs_control_cleanup();
/* common rcu_barrier() used by:
* - ip_vs_control_cleanup()
*/
rcu_barrier();
pr_info("ipvs unloaded.\n");
}
module_init(ip_vs_init);
module_exit(ip_vs_cleanup);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("IP Virtual Server");
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