/*
* IPVS main scheduling function
* It selects a server according to the virtual service, and
* creates a connection entry.
* Protocols supported: TCP, UDP
*/
struct ip_vs_conn *
ip_vs_schedule(struct ip_vs_service *svc, const struct sk_buff *skb)
{
struct ip_vs_conn *cp = NULL;
struct iphdr *iph = ip_hdr(skb);
struct ip_vs_dest *dest;
__be16 _ports[2], *pptr;
pptr = skb_header_pointer(skb, iph->ihl*4,
sizeof(_ports), _ports);
if (pptr == NULL)
return NULL;
/*
* Persistent service
*/
if (svc->flags & IP_VS_SVC_F_PERSISTENT)
return ip_vs_sched_persist(svc, skb, pptr);
/*
* Non-persistent service
*/
if (!svc->fwmark && pptr[1] != svc->port) {
if (!svc->port)
IP_VS_ERR("Schedule: port zero only supported "
"in persistent services, "
"check your ipvs configuration\n");
return NULL;
}
dest = svc->scheduler->schedule(svc, skb);
if (dest == NULL) {
IP_VS_DBG(1, "Schedule: no dest found.\n");
return NULL;
}
/*
* Create a connection entry.
*/
cp = ip_vs_conn_new(iph->protocol,
iph->saddr, pptr[0],
iph->daddr, pptr[1],
dest->addr, dest->port?dest->port:pptr[1],
0,
dest);
if (cp == NULL)
return NULL;
IP_VS_DBG(6, "Schedule fwd:%c c:%u.%u.%u.%u:%u v:%u.%u.%u.%u:%u "
"d:%u.%u.%u.%u:%u conn->flags:%X conn->refcnt:%d\n",
ip_vs_fwd_tag(cp),
NIPQUAD(cp->caddr), ntohs(cp->cport),
NIPQUAD(cp->vaddr), ntohs(cp->vport),
NIPQUAD(cp->daddr), ntohs(cp->dport),
cp->flags, atomic_read(&cp->refcnt));
ip_vs_conn_stats(cp, svc);
return cp;
}
/*
* 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,
const struct sk_buff *skb,
__be16 ports[2])
{
struct ip_vs_conn *cp = NULL;
struct iphdr *iph = ip_hdr(skb);
struct ip_vs_dest *dest;
struct ip_vs_conn *ct;
__be16 dport; /* destination port to forward */
__be32 snet; /* source network of the client, after masking */
/* Mask saddr with the netmask to adjust template granularity */
snet = iph->saddr & svc->netmask;
IP_VS_DBG(6, "p-schedule: src %u.%u.%u.%u:%u dest %u.%u.%u.%u:%u "
"mnet %u.%u.%u.%u\n",
NIPQUAD(iph->saddr), ntohs(ports[0]),
NIPQUAD(iph->daddr), ntohs(ports[1]),
NIPQUAD(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.
*/
if (ports[1] == svc->port) {
/* Check if a template already exists */
if (svc->port != FTPPORT)
ct = ip_vs_ct_in_get(iph->protocol, snet, 0,
iph->daddr, ports[1]);
else
ct = ip_vs_ct_in_get(iph->protocol, snet, 0,
iph->daddr, 0);
if (!ct || !ip_vs_check_template(ct)) {
/*
* No template found or the dest of the connection
* template is not available.
*/
dest = svc->scheduler->schedule(svc, skb);
if (dest == NULL) {
IP_VS_DBG(1, "p-schedule: no dest found.\n");
return NULL;
}
/*
* Create a template like <protocol,caddr,0,
* vaddr,vport,daddr,dport> for non-ftp service,
* and <protocol,caddr,0,vaddr,0,daddr,0>
* for ftp service.
*/
if (svc->port != FTPPORT)
ct = ip_vs_conn_new(iph->protocol,
snet, 0,
iph->daddr,
ports[1],
dest->addr, dest->port,
IP_VS_CONN_F_TEMPLATE,
dest);
else
ct = ip_vs_conn_new(iph->protocol,
snet, 0,
iph->daddr, 0,
dest->addr, 0,
IP_VS_CONN_F_TEMPLATE,
dest);
if (ct == NULL)
return NULL;
ct->timeout = svc->timeout;
} else {
/* set destination with the found template */
dest = ct->dest;
}
dport = dest->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)
ct = ip_vs_ct_in_get(IPPROTO_IP, snet, 0,
htonl(svc->fwmark), 0);
else
ct = ip_vs_ct_in_get(iph->protocol, snet, 0,
iph->daddr, 0);
if (!ct || !ip_vs_check_template(ct)) {
/*
* If it is not persistent port zero, return NULL,
* otherwise create a connection template.
*/
if (svc->port)
return NULL;
dest = svc->scheduler->schedule(svc, skb);
if (dest == NULL) {
IP_VS_DBG(1, "p-schedule: no dest found.\n");
return NULL;
}
/*
* Create a template according to the service
*/
if (svc->fwmark)
ct = ip_vs_conn_new(IPPROTO_IP,
snet, 0,
htonl(svc->fwmark), 0,
dest->addr, 0,
IP_VS_CONN_F_TEMPLATE,
dest);
else
ct = ip_vs_conn_new(iph->protocol,
snet, 0,
iph->daddr, 0,
dest->addr, 0,
IP_VS_CONN_F_TEMPLATE,
dest);
if (ct == NULL)
return NULL;
ct->timeout = svc->timeout;
} else {
/* set destination with the found template */
dest = ct->dest;
}
dport = ports[1];
}
/*
* Create a new connection according to the template
*/
cp = ip_vs_conn_new(iph->protocol,
iph->saddr, ports[0],
iph->daddr, ports[1],
dest->addr, dport,
0,
dest);
if (cp == NULL) {
ip_vs_conn_put(ct);
return NULL;
}
/*
* Add its control
*/
ip_vs_control_add(cp, ct);
ip_vs_conn_put(ct);
ip_vs_conn_stats(cp, svc);
return cp;
}
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_conn *cp = NULL;
struct ip_vs_iphdr iph;
struct ip_vs_dest *dest;
struct ip_vs_conn *ct;
__be16 dport = 0;
unsigned int flags;
struct ip_vs_conn_param param;
const union nf_inet_addr fwmark = { .ip = htonl(svc->fwmark) };
union nf_inet_addr snet;
ip_vs_fill_iphdr(svc->af, skb_network_header(skb), &iph);
#ifdef CONFIG_IP_VS_IPV6
if (svc->af == AF_INET6)
ipv6_addr_prefix(&snet.in6, &iph.saddr.in6, svc->netmask);
else
#endif
snet.ip = iph.saddr.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, &iph.saddr), ntohs(src_port),
IP_VS_DBG_ADDR(svc->af, &iph.daddr), ntohs(dst_port),
IP_VS_DBG_ADDR(svc->af, &snet));
{
int protocol = iph.protocol;
const union nf_inet_addr *vaddr = &iph.daddr;
__be16 vport = 0;
if (dst_port == svc->port) {
if (svc->port != FTPPORT)
vport = dst_port;
} else {
if (svc->fwmark) {
protocol = IPPROTO_IP;
vaddr = &fwmark;
}
}
if (ip_vs_conn_fill_param_persist(svc, skb, protocol, &snet, 0,
vaddr, vport, ¶m) < 0) {
*ignored = -1;
return NULL;
}
}
ct = ip_vs_ct_in_get(¶m);
if (!ct || !ip_vs_check_template(ct)) {
dest = svc->scheduler->schedule(svc, skb);
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;
ct = ip_vs_conn_new(¶m, &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 {
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;
ip_vs_conn_fill_param(svc->net, svc->af, iph.protocol, &iph.saddr,
src_port, &iph.daddr, dst_port, ¶m);
cp = ip_vs_conn_new(¶m, &dest->addr, dport, flags, dest, skb->mark);
if (cp == NULL) {
ip_vs_conn_put(ct);
*ignored = -1;
return NULL;
}
ip_vs_control_add(cp, ct);
ip_vs_conn_put(ct);
ip_vs_conn_stats(cp, svc);
return cp;
}
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_protocol *pp = pd->pp;
struct ip_vs_conn *cp = NULL;
struct ip_vs_iphdr iph;
struct ip_vs_dest *dest;
__be16 _ports[2], *pptr;
unsigned int flags;
*ignored = 1;
ip_vs_fill_iphdr(svc->af, skb_network_header(skb), &iph);
pptr = skb_header_pointer(skb, iph.len, sizeof(_ports), _ports);
if (pptr == NULL)
return NULL;
if (pptr[0] == FTPDATA) {
IP_VS_DBG_PKT(12, svc->af, pp, skb, 0,
"Not scheduling FTPDATA");
return NULL;
}
if ((!skb->dev || skb->dev->flags & IFF_LOOPBACK) &&
(cp = pp->conn_in_get(svc->af, skb, &iph, iph.len, 1))) {
IP_VS_DBG_PKT(12, svc->af, pp, skb, 0,
"Not scheduling reply for existing connection");
__ip_vs_conn_put(cp);
return NULL;
}
if (svc->flags & IP_VS_SVC_F_PERSISTENT)
return ip_vs_sched_persist(svc, skb, pptr[0], pptr[1], ignored);
*ignored = 0;
if (!svc->fwmark && pptr[1] != svc->port) {
if (!svc->port)
pr_err("Schedule: port zero only supported "
"in persistent services, "
"check your ipvs configuration\n");
return NULL;
}
dest = svc->scheduler->schedule(svc, skb);
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;
{
struct ip_vs_conn_param p;
ip_vs_conn_fill_param(svc->net, svc->af, iph.protocol,
&iph.saddr, pptr[0], &iph.daddr, pptr[1],
&p);
cp = ip_vs_conn_new(&p, &dest->addr,
dest->port ? dest->port : pptr[1],
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(svc->af, &cp->caddr), ntohs(cp->cport),
IP_VS_DBG_ADDR(svc->af, &cp->vaddr), ntohs(cp->vport),
IP_VS_DBG_ADDR(svc->af, &cp->daddr), ntohs(cp->dport),
cp->flags, atomic_read(&cp->refcnt));
ip_vs_conn_stats(cp, svc);
return cp;
}
int ip_vs_leave(struct ip_vs_service *svc, struct sk_buff *skb,
struct ip_vs_proto_data *pd)
{
__be16 _ports[2], *pptr;
struct ip_vs_iphdr iph;
#ifdef CONFIG_SYSCTL
struct net *net;
struct netns_ipvs *ipvs;
int unicast;
#endif
ip_vs_fill_iphdr(svc->af, skb_network_header(skb), &iph);
pptr = skb_header_pointer(skb, iph.len, sizeof(_ports), _ports);
if (pptr == NULL) {
ip_vs_service_put(svc);
return NF_DROP;
}
#ifdef CONFIG_SYSCTL
net = skb_net(skb);
#ifdef CONFIG_IP_VS_IPV6
if (svc->af == AF_INET6)
unicast = ipv6_addr_type(&iph.daddr.in6) & IPV6_ADDR_UNICAST;
else
#endif
unicast = (inet_addr_type(net, iph.daddr.ip) == RTN_UNICAST);
ipvs = net_ipvs(net);
if (ipvs->sysctl_cache_bypass && svc->fwmark && unicast) {
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 } };
ip_vs_service_put(svc);
IP_VS_DBG(6, "%s(): create a cache_bypass entry\n", __func__);
{
struct ip_vs_conn_param p;
ip_vs_conn_fill_param(svc->net, svc->af, iph.protocol,
&iph.saddr, pptr[0],
&iph.daddr, pptr[1], &p);
cp = ip_vs_conn_new(&p, &daddr, 0,
IP_VS_CONN_F_BYPASS | flags,
NULL, skb->mark);
if (!cp)
return NF_DROP;
}
ip_vs_in_stats(cp, skb);
ip_vs_set_state(cp, IP_VS_DIR_INPUT, skb, pd);
ret = cp->packet_xmit(skb, cp, pd->pp);
atomic_inc(&cp->in_pkts);
ip_vs_conn_put(cp);
return ret;
}
/*
* Check if it's for virtual services, look it up,
* and send it on its way...
*/
static unsigned int ip_vs_in(unsigned int hooknum,
struct sk_buff **skb_p,
const struct net_device *in,
const struct net_device *out,
int (*okfn)(struct sk_buff *))
{
struct sk_buff *skb = *skb_p;
struct iphdr *iph = skb->nh.iph;
union ip_vs_tphdr h;
struct ip_vs_conn *cp;
struct ip_vs_service *svc;
int ihl;
int ret;
/*
* Big tappo: only PACKET_HOST (nor loopback neither mcasts)
* ... don't know why 1st test DOES NOT include 2nd (?)
*/
if (skb->pkt_type != PACKET_HOST || skb->dev == &loopback_dev) {
IP_VS_DBG(12, "packet type=%d proto=%d daddr=%d.%d.%d.%d ignored\n",
skb->pkt_type,
iph->protocol,
NIPQUAD(iph->daddr));
return NF_ACCEPT;
}
if (iph->protocol == IPPROTO_ICMP)
return ip_vs_in_icmp(skb_p);
/* let it go if other IP protocols */
if (iph->protocol != IPPROTO_TCP && iph->protocol != IPPROTO_UDP)
return NF_ACCEPT;
/* make sure that protocol header available in skb data area,
note that skb data area may be reallocated. */
ihl = iph->ihl << 2;
if (ip_vs_header_check(skb, iph->protocol, ihl) == -1)
return NF_DROP;
iph = skb->nh.iph;
h.raw = (char*) iph + ihl;
/*
* Check if the packet belongs to an existing connection entry
*/
cp = ip_vs_conn_in_get(iph->protocol, iph->saddr, h.portp[0],
iph->daddr, h.portp[1]);
if (!cp &&
(h.th->syn || (iph->protocol!=IPPROTO_TCP)) &&
(svc = ip_vs_service_get(skb->nfmark, iph->protocol,
iph->daddr, h.portp[1]))) {
if (ip_vs_todrop()) {
/*
* It seems that we are very loaded.
* We have to drop this packet :(
*/
ip_vs_service_put(svc);
return NF_DROP;
}
/*
* Let the virtual server select a real server for the
* incoming connection, and create a connection entry.
*/
cp = ip_vs_schedule(svc, iph);
if (!cp)
return ip_vs_leave(svc, skb);
ip_vs_conn_stats(cp, svc);
ip_vs_service_put(svc);
}
if (!cp) {
/* sorry, all this trouble for a no-hit :) */
IP_VS_DBG(12, "packet for %s %d.%d.%d.%d:%d continue "
"traversal as normal.\n",
ip_vs_proto_name(iph->protocol),
NIPQUAD(iph->daddr),
ntohs(h.portp[1]));
return NF_ACCEPT;
}
IP_VS_DBG(11, "Incoming %s %u.%u.%u.%u:%d->%u.%u.%u.%u:%d\n",
ip_vs_proto_name(iph->protocol),
NIPQUAD(iph->saddr), ntohs(h.portp[0]),
NIPQUAD(iph->daddr), ntohs(h.portp[1]));
/* Check the server status */
if (cp->dest && !(cp->dest->flags & IP_VS_DEST_F_AVAILABLE)) {
/* the destination server is not available */
if (sysctl_ip_vs_expire_nodest_conn) {
/* try to expire the connection immediately */
ip_vs_conn_expire_now(cp);
} else {
/* don't restart its timer, and silently
drop the packet. */
__ip_vs_conn_put(cp);
}
return NF_DROP;
}
ip_vs_in_stats(cp, skb);
ip_vs_set_state(cp, VS_STATE_INPUT, iph, h.portp);
if (cp->packet_xmit)
ret = cp->packet_xmit(skb, cp);
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 */
atomic_inc(&cp->in_pkts);
if (ip_vs_sync_state & IP_VS_STATE_MASTER &&
(cp->protocol != IPPROTO_TCP ||
cp->state == IP_VS_S_ESTABLISHED) &&
(atomic_read(&cp->in_pkts) % 50 == sysctl_ip_vs_sync_threshold))
ip_vs_sync_conn(cp);
ip_vs_conn_put(cp);
return ret;
}
/*
* 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 */
/* Mask saddr with the netmask to adjust template granularity */
#ifdef CONFIG_IP_VS_IPV6
if (svc->af == AF_INET6)
ipv6_addr_prefix(&snet.in6, &iph->saddr.in6,
(__force __u32) svc->netmask);
else
#endif
snet.ip = iph->saddr.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, &iph->saddr), ntohs(src_port),
IP_VS_DBG_ADDR(svc->af, &iph->daddr), 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 = &iph->daddr;
__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)) {
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->net, svc->af, iph->protocol, &iph->saddr,
src_port, &iph->daddr, 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;
unsigned int flags;
*ignored = 1;
/*
* IPv6 frags, only the first hit here.
*/
pptr = frag_safe_skb_hp(skb, iph->len, sizeof(_ports), _ports, iph);
if (pptr == NULL)
return NULL;
/*
* 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 (pptr[0] == FTPDATA) {
IP_VS_DBG_PKT(12, svc->af, pp, skb, 0,
"Not scheduling FTPDATA");
return NULL;
}
/*
* Do not schedule replies from local real server.
*/
if ((!skb->dev || skb->dev->flags & IFF_LOOPBACK) &&
(cp = pp->conn_in_get(svc->af, skb, iph, 1))) {
IP_VS_DBG_PKT(12, svc->af, pp, skb, 0,
"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, pptr[0], pptr[1], ignored,
iph);
*ignored = 0;
/*
* Non-persistent service
*/
if (!svc->fwmark && pptr[1] != 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->net, svc->af, iph->protocol,
&iph->saddr, pptr[0], &iph->daddr,
pptr[1], &p);
cp = ip_vs_conn_new(&p, dest->af, &dest->addr,
dest->port ? dest->port : pptr[1],
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, atomic_read(&cp->refcnt));
ip_vs_conn_stats(cp, svc);
return cp;
}
/*
* 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;
#ifdef CONFIG_SYSCTL
struct net *net;
struct netns_ipvs *ipvs;
int unicast;
#endif
pptr = frag_safe_skb_hp(skb, iph->len, sizeof(_ports), _ports, iph);
if (pptr == NULL) {
return NF_DROP;
}
#ifdef CONFIG_SYSCTL
net = skb_net(skb);
#ifdef CONFIG_IP_VS_IPV6
if (svc->af == AF_INET6)
unicast = ipv6_addr_type(&iph->daddr.in6) & IPV6_ADDR_UNICAST;
else
#endif
unicast = (inet_addr_type(net, iph->daddr.ip) == RTN_UNICAST);
/* 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 */
ipvs = net_ipvs(net);
if (ipvs->sysctl_cache_bypass && svc->fwmark && unicast) {
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->net, 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 */
atomic_inc(&cp->in_pkts);
ip_vs_conn_put(cp);
return ret;
}
