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 = net_ipvs(skb_net(skb)); if (dest && (dest->flags & IP_VS_DEST_F_AVAILABLE)) { struct ip_vs_cpu_stats *s; s = this_cpu_ptr(dest->stats.cpustats); s->ustats.outpkts++; u64_stats_update_begin(&s->syncp); s->ustats.outbytes += skb->len; u64_stats_update_end(&s->syncp); s = this_cpu_ptr(dest->svc->stats.cpustats); s->ustats.outpkts++; u64_stats_update_begin(&s->syncp); s->ustats.outbytes += skb->len; u64_stats_update_end(&s->syncp); s = this_cpu_ptr(ipvs->tot_stats.cpustats); s->ustats.outpkts++; u64_stats_update_begin(&s->syncp); s->ustats.outbytes += skb->len; u64_stats_update_end(&s->syncp); } }
static struct ip_vs_conn * ah_esp_conn_in_get(int af, const struct sk_buff *skb, const struct ip_vs_iphdr *iph, unsigned int proto_off, int inverse) { struct ip_vs_conn *cp; struct ip_vs_conn_param p; struct net *net = skb_net(skb); ah_esp_conn_fill_param_proto(net, af, iph, inverse, &p); cp = ip_vs_conn_in_get(&p); if (!cp) { /* * We are not sure if the packet is from our * service, so our conn_schedule hook should return NF_ACCEPT */ IP_VS_DBG_BUF(12, "Unknown ISAKMP entry for outin packet " "%s%s %s->%s\n", inverse ? "ICMP+" : "", ip_vs_proto_get(iph->protocol)->name, IP_VS_DBG_ADDR(af, &iph->saddr), IP_VS_DBG_ADDR(af, &iph->daddr)); } return cp; }
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 = net_ipvs(skb_net(skb)); if (dest && (dest->flags & IP_VS_DEST_F_AVAILABLE)) { struct ip_vs_cpu_stats *s; struct ip_vs_service *svc; s = this_cpu_ptr(dest->stats.cpustats); u64_stats_update_begin(&s->syncp); s->cnt.outpkts++; s->cnt.outbytes += skb->len; u64_stats_update_end(&s->syncp); rcu_read_lock(); svc = rcu_dereference(dest->svc); s = this_cpu_ptr(svc->stats.cpustats); u64_stats_update_begin(&s->syncp); s->cnt.outpkts++; s->cnt.outbytes += skb->len; u64_stats_update_end(&s->syncp); rcu_read_unlock(); s = this_cpu_ptr(ipvs->tot_stats.cpustats); u64_stats_update_begin(&s->syncp); s->cnt.outpkts++; s->cnt.outbytes += skb->len; u64_stats_update_end(&s->syncp); } }
static int sctp_conn_schedule(int af, struct sk_buff *skb, struct ip_vs_proto_data *pd, int *verdict, struct ip_vs_conn **cpp) { struct net *net; struct ip_vs_service *svc; sctp_chunkhdr_t _schunkh, *sch; sctp_sctphdr_t *sh, _sctph; struct ip_vs_iphdr iph; ip_vs_fill_iphdr(af, skb_network_header(skb), &iph); sh = skb_header_pointer(skb, iph.len, sizeof(_sctph), &_sctph); if (sh == NULL) return 0; sch = skb_header_pointer(skb, iph.len + sizeof(sctp_sctphdr_t), sizeof(_schunkh), &_schunkh); if (sch == NULL) return 0; net = skb_net(skb); if ((sch->type == SCTP_CID_INIT) && (svc = ip_vs_service_get(net, af, skb->mark, iph.protocol, &iph.daddr, sh->dest))) { int ignored; if (ip_vs_todrop(net_ipvs(net))) { /* * It seems that we are very loaded. * We have to drop this packet :( */ ip_vs_service_put(svc); *verdict = NF_DROP; return 0; } /* * Let the virtual server select a real server for the * incoming connection, and create a connection entry. */ *cpp = ip_vs_schedule(svc, skb, pd, &ignored); if (!*cpp && ignored <= 0) { if (!ignored) *verdict = ip_vs_leave(svc, skb, pd); else { ip_vs_service_put(svc); *verdict = NF_DROP; } return 0; } ip_vs_service_put(svc); } /* NF_ACCEPT */ return 1; }
static inline bool ensure_mtu_is_adequate(int skb_af, int rt_mode, struct ip_vs_iphdr *ipvsh, struct sk_buff *skb, int mtu) { #ifdef CONFIG_IP_VS_IPV6 if (skb_af == AF_INET6) { struct net *net = dev_net(skb_dst(skb)->dev); if (unlikely(__mtu_check_toobig_v6(skb, mtu))) { if (!skb->dev) skb->dev = net->loopback_dev; /* only send ICMP too big on first fragment */ if (!ipvsh->fragoffs) icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); IP_VS_DBG(1, "frag needed for %pI6c\n", &ipv6_hdr(skb)->saddr); return false; } } else #endif { struct netns_ipvs *ipvs = net_ipvs(skb_net(skb)); /* If we're going to tunnel the packet and pmtu discovery * is disabled, we'll just fragment it anyway */ if ((rt_mode & IP_VS_RT_MODE_TUNNEL) && !sysctl_pmtu_disc(ipvs)) return true; if (unlikely(ip_hdr(skb)->frag_off & htons(IP_DF) && skb->len > mtu && !skb_is_gso(skb))) { icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu)); IP_VS_DBG(1, "frag needed for %pI4\n", &ip_hdr(skb)->saddr); return false; } } return true; }
static struct ip_vs_conn * ah_esp_conn_out_get(int af, const struct sk_buff *skb, const struct ip_vs_iphdr *iph, unsigned int proto_off, int inverse) { struct ip_vs_conn *cp; struct ip_vs_conn_param p; struct net *net = skb_net(skb); ah_esp_conn_fill_param_proto(net, af, iph, inverse, &p); cp = ip_vs_conn_out_get(&p); if (!cp) { IP_VS_DBG_BUF(12, "Unknown ISAKMP entry for inout packet " "%s%s %s->%s\n", inverse ? "ICMP+" : "", ip_vs_proto_get(iph->protocol)->name, IP_VS_DBG_ADDR(af, &iph->saddr), IP_VS_DBG_ADDR(af, &iph->daddr)); } return cp; }
/* * Look at outgoing ftp packets to catch the response to a PASV command * from the server (inside-to-outside). * When we see one, we build a connection entry with the client address, * client port 0 (unknown at the moment), the server address and the * server port. Mark the current connection entry as a control channel * of the new entry. All this work is just to make the data connection * can be scheduled to the right server later. * * The outgoing packet should be something like * "227 Entering Passive Mode (xxx,xxx,xxx,xxx,ppp,ppp)". * xxx,xxx,xxx,xxx is the server address, ppp,ppp is the server port number. */ static int ip_vs_ftp_out(struct ip_vs_app *app, struct ip_vs_conn *cp, struct sk_buff *skb, int *diff) { struct iphdr *iph; struct tcphdr *th; char *data, *data_limit; char *start, *end; union nf_inet_addr from; __be16 port; struct ip_vs_conn *n_cp; char buf[24]; /* xxx.xxx.xxx.xxx,ppp,ppp\000 */ unsigned buf_len; int ret = 0; enum ip_conntrack_info ctinfo; struct nf_conn *ct; struct net *net; #ifdef CONFIG_IP_VS_IPV6 /* This application helper doesn't work with IPv6 yet, * so turn this into a no-op for IPv6 packets */ if (cp->af == AF_INET6) return 1; #endif *diff = 0; /* Only useful for established sessions */ if (cp->state != IP_VS_TCP_S_ESTABLISHED) return 1; /* Linear packets are much easier to deal with. */ if (!skb_make_writable(skb, skb->len)) return 0; if (cp->app_data == &ip_vs_ftp_pasv) { iph = ip_hdr(skb); th = (struct tcphdr *)&(((char *)iph)[iph->ihl*4]); data = (char *)th + (th->doff << 2); data_limit = skb_tail_pointer(skb); if (ip_vs_ftp_get_addrport(data, data_limit, SERVER_STRING, sizeof(SERVER_STRING)-1, '(', ')', &from.ip, &port, &start, &end) != 1) return 1; IP_VS_DBG(7, "PASV response (%pI4:%d) -> %pI4:%d detected\n", &from.ip, ntohs(port), &cp->caddr.ip, 0); /* * Now update or create an connection entry for it */ { struct ip_vs_conn_param p; ip_vs_conn_fill_param(ip_vs_conn_net(cp), AF_INET, iph->protocol, &from, port, &cp->caddr, 0, &p); n_cp = ip_vs_conn_out_get(&p); } if (!n_cp) { struct ip_vs_conn_param p; ip_vs_conn_fill_param(ip_vs_conn_net(cp), AF_INET, IPPROTO_TCP, &cp->caddr, 0, &cp->vaddr, port, &p); n_cp = ip_vs_conn_new(&p, &from, port, IP_VS_CONN_F_NO_CPORT | IP_VS_CONN_F_NFCT, cp->dest, skb->mark); if (!n_cp) return 0; /* add its controller */ ip_vs_control_add(n_cp, cp); } /* * Replace the old passive address with the new one */ from.ip = n_cp->vaddr.ip; port = n_cp->vport; snprintf(buf, sizeof(buf), "%u,%u,%u,%u,%u,%u", ((unsigned char *)&from.ip)[0], ((unsigned char *)&from.ip)[1], ((unsigned char *)&from.ip)[2], ((unsigned char *)&from.ip)[3], ntohs(port) >> 8, ntohs(port) & 0xFF); buf_len = strlen(buf); ct = nf_ct_get(skb, &ctinfo); if (ct && !nf_ct_is_untracked(ct) && nfct_nat(ct)) { /* If mangling fails this function will return 0 * which will cause the packet to be dropped. * Mangling can only fail under memory pressure, * hopefully it will succeed on the retransmitted * packet. */ ret = nf_nat_mangle_tcp_packet(skb, ct, ctinfo, start-data, end-start, buf, buf_len); if (ret) { ip_vs_nfct_expect_related(skb, ct, n_cp, IPPROTO_TCP, 0, 0); if (skb->ip_summed == CHECKSUM_COMPLETE) skb->ip_summed = CHECKSUM_UNNECESSARY; /* csum is updated */ ret = 1; } } /* * Not setting 'diff' is intentional, otherwise the sequence * would be adjusted twice. */ net = skb_net(skb); cp->app_data = NULL; ip_vs_tcp_conn_listen(net, n_cp); ip_vs_conn_put(n_cp); return ret; }
/* * IP Tunneling transmitter * * This function encapsulates the packet in a new IP packet, its * destination will be set to cp->daddr. Most code of this function * is taken from ipip.c. * * It is used in VS/TUN cluster. The load balancer selects a real * server from a cluster based on a scheduling algorithm, * encapsulates the request packet and forwards it to the selected * server. For example, all real servers are configured with * "ifconfig tunl0 <Virtual IP Address> up". When the server receives * the encapsulated packet, it will decapsulate the packet, processe * the request and return the response packets directly to the client * without passing the load balancer. This can greatly increase the * scalability of virtual server. * * Used for ANY protocol */ int ip_vs_tunnel_xmit(struct sk_buff *skb, struct ip_vs_conn *cp, struct ip_vs_protocol *pp, struct ip_vs_iphdr *ipvsh) { struct netns_ipvs *ipvs = net_ipvs(skb_net(skb)); struct rtable *rt; /* Route to the other host */ __be32 saddr; /* Source for tunnel */ struct net_device *tdev; /* Device to other host */ struct iphdr *old_iph = ip_hdr(skb); u8 tos = old_iph->tos; __be16 df; struct iphdr *iph; /* Our new IP header */ unsigned int max_headroom; /* The extra header space needed */ int ret, local; EnterFunction(10); rcu_read_lock(); local = __ip_vs_get_out_rt(skb, cp->dest, cp->daddr.ip, IP_VS_RT_MODE_LOCAL | IP_VS_RT_MODE_NON_LOCAL | IP_VS_RT_MODE_CONNECT | IP_VS_RT_MODE_TUNNEL, &saddr); if (local < 0) goto tx_error; if (local) { rcu_read_unlock(); return ip_vs_send_or_cont(NFPROTO_IPV4, skb, cp, 1); } rt = skb_rtable(skb); tdev = rt->dst.dev; /* Copy DF, reset fragment offset and MF */ df = sysctl_pmtu_disc(ipvs) ? old_iph->frag_off & htons(IP_DF) : 0; /* * Okay, now see if we can stuff it in the buffer as-is. */ max_headroom = LL_RESERVED_SPACE(tdev) + sizeof(struct iphdr); if (skb_headroom(skb) < max_headroom || skb_cloned(skb)) { struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom); if (!new_skb) goto tx_error; consume_skb(skb); skb = new_skb; old_iph = ip_hdr(skb); } skb->transport_header = skb->network_header; /* fix old IP header checksum */ ip_send_check(old_iph); skb_push(skb, sizeof(struct iphdr)); skb_reset_network_header(skb); memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); /* * Push down and install the IPIP header. */ iph = ip_hdr(skb); iph->version = 4; iph->ihl = sizeof(struct iphdr)>>2; iph->frag_off = df; iph->protocol = IPPROTO_IPIP; iph->tos = tos; iph->daddr = cp->daddr.ip; iph->saddr = saddr; iph->ttl = old_iph->ttl; ip_select_ident(skb, &rt->dst, NULL); /* Another hack: avoid icmp_send in ip_fragment */ skb->local_df = 1; ret = ip_vs_tunnel_xmit_prepare(skb, cp); if (ret == NF_ACCEPT) ip_local_out(skb); else if (ret == NF_DROP) kfree_skb(skb); rcu_read_unlock(); LeaveFunction(10); return NF_STOLEN; tx_error: kfree_skb(skb); rcu_read_unlock(); LeaveFunction(10); return NF_STOLEN; }
/* * IP Tunneling transmitter * * This function encapsulates the packet in a new IP packet, its * destination will be set to cp->daddr. Most code of this function * is taken from ipip.c. * * It is used in VS/TUN cluster. The load balancer selects a real * server from a cluster based on a scheduling algorithm, * encapsulates the request packet and forwards it to the selected * server. For example, all real servers are configured with * "ifconfig tunl0 <Virtual IP Address> up". When the server receives * the encapsulated packet, it will decapsulate the packet, processe * the request and return the response packets directly to the client * without passing the load balancer. This can greatly increase the * scalability of virtual server. * * Used for ANY protocol */ int ip_vs_tunnel_xmit(struct sk_buff *skb, struct ip_vs_conn *cp, struct ip_vs_protocol *pp, struct ip_vs_iphdr *ipvsh) { struct net *net = skb_net(skb); struct netns_ipvs *ipvs = net_ipvs(net); struct rtable *rt; /* Route to the other host */ __be32 saddr; /* Source for tunnel */ struct net_device *tdev; /* Device to other host */ __u8 next_protocol = 0; __u8 dsfield = 0; __u8 ttl = 0; __be16 df = 0; __be16 *dfp = NULL; struct iphdr *iph; /* Our new IP header */ unsigned int max_headroom; /* The extra header space needed */ int ret, local; EnterFunction(10); rcu_read_lock(); local = __ip_vs_get_out_rt(cp->af, skb, cp->dest, cp->daddr.ip, IP_VS_RT_MODE_LOCAL | IP_VS_RT_MODE_NON_LOCAL | IP_VS_RT_MODE_CONNECT | IP_VS_RT_MODE_TUNNEL, &saddr, ipvsh); if (local < 0) goto tx_error; if (local) { rcu_read_unlock(); return ip_vs_send_or_cont(NFPROTO_IPV4, skb, cp, 1); } rt = skb_rtable(skb); tdev = rt->dst.dev; /* * Okay, now see if we can stuff it in the buffer as-is. */ max_headroom = LL_RESERVED_SPACE(tdev) + sizeof(struct iphdr); /* We only care about the df field if sysctl_pmtu_disc(ipvs) is set */ dfp = sysctl_pmtu_disc(ipvs) ? &df : NULL; skb = ip_vs_prepare_tunneled_skb(skb, cp->af, max_headroom, &next_protocol, NULL, &dsfield, &ttl, dfp); if (IS_ERR(skb)) goto tx_error; skb = iptunnel_handle_offloads( skb, false, __tun_gso_type_mask(AF_INET, cp->af)); if (IS_ERR(skb)) goto tx_error; skb->transport_header = skb->network_header; skb_push(skb, sizeof(struct iphdr)); skb_reset_network_header(skb); memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); /* * Push down and install the IPIP header. */ iph = ip_hdr(skb); iph->version = 4; iph->ihl = sizeof(struct iphdr)>>2; iph->frag_off = df; iph->protocol = next_protocol; iph->tos = dsfield; iph->daddr = cp->daddr.ip; iph->saddr = saddr; iph->ttl = ttl; ip_select_ident(net, skb, NULL); /* Another hack: avoid icmp_send in ip_fragment */ skb->ignore_df = 1; ret = ip_vs_tunnel_xmit_prepare(skb, cp); if (ret == NF_ACCEPT) ip_local_out(skb); else if (ret == NF_DROP) kfree_skb(skb); rcu_read_unlock(); LeaveFunction(10); return NF_STOLEN; tx_error: if (!IS_ERR(skb)) kfree_skb(skb); rcu_read_unlock(); LeaveFunction(10); return NF_STOLEN; }
/* * IP Tunneling transmitter * * This function encapsulates the packet in a new IP packet, its * destination will be set to cp->daddr. Most code of this function * is taken from ipip.c. * * It is used in VS/TUN cluster. The load balancer selects a real * server from a cluster based on a scheduling algorithm, * encapsulates the request packet and forwards it to the selected * server. For example, all real servers are configured with * "ifconfig tunl0 <Virtual IP Address> up". When the server receives * the encapsulated packet, it will decapsulate the packet, processe * the request and return the response packets directly to the client * without passing the load balancer. This can greatly increase the * scalability of virtual server. * * Used for ANY protocol */ int ip_vs_tunnel_xmit(struct sk_buff *skb, struct ip_vs_conn *cp, struct ip_vs_protocol *pp) { struct netns_ipvs *ipvs = net_ipvs(skb_net(skb)); struct rtable *rt; /* Route to the other host */ __be32 saddr; /* Source for tunnel */ struct net_device *tdev; /* Device to other host */ struct iphdr *old_iph = ip_hdr(skb); u8 tos = old_iph->tos; __be16 df; struct iphdr *iph; /* Our new IP header */ unsigned int max_headroom; /* The extra header space needed */ int mtu; int ret; EnterFunction(10); if (!(rt = __ip_vs_get_out_rt(skb, cp->dest, cp->daddr.ip, RT_TOS(tos), IP_VS_RT_MODE_LOCAL | IP_VS_RT_MODE_NON_LOCAL | IP_VS_RT_MODE_CONNECT, &saddr))) goto tx_error_icmp; if (rt->rt_flags & RTCF_LOCAL) { ip_rt_put(rt); IP_VS_XMIT(NFPROTO_IPV4, skb, cp, 1); } tdev = rt->dst.dev; mtu = dst_mtu(&rt->dst) - sizeof(struct iphdr); if (mtu < 68) { IP_VS_DBG_RL("%s(): mtu less than 68\n", __func__); goto tx_error_put; } if (rt_is_output_route(skb_rtable(skb))) skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu); /* Copy DF, reset fragment offset and MF */ df = sysctl_pmtu_disc(ipvs) ? old_iph->frag_off & htons(IP_DF) : 0; if (df && mtu < ntohs(old_iph->tot_len) && !skb_is_gso(skb)) { icmp_send(skb, ICMP_DEST_UNREACH,ICMP_FRAG_NEEDED, htonl(mtu)); IP_VS_DBG_RL("%s(): frag needed\n", __func__); goto tx_error_put; } /* * Okay, now see if we can stuff it in the buffer as-is. */ max_headroom = LL_RESERVED_SPACE(tdev) + sizeof(struct iphdr); if (skb_headroom(skb) < max_headroom || skb_cloned(skb) || skb_shared(skb)) { struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom); if (!new_skb) { ip_rt_put(rt); kfree_skb(skb); IP_VS_ERR_RL("%s(): no memory\n", __func__); return NF_STOLEN; } consume_skb(skb); skb = new_skb; old_iph = ip_hdr(skb); } skb->transport_header = skb->network_header; /* fix old IP header checksum */ ip_send_check(old_iph); skb_push(skb, sizeof(struct iphdr)); skb_reset_network_header(skb); memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); /* drop old route */ skb_dst_drop(skb); skb_dst_set(skb, &rt->dst); /* * Push down and install the IPIP header. */ iph = ip_hdr(skb); iph->version = 4; iph->ihl = sizeof(struct iphdr)>>2; iph->frag_off = df; iph->protocol = IPPROTO_IPIP; iph->tos = tos; iph->daddr = cp->daddr.ip; iph->saddr = saddr; iph->ttl = old_iph->ttl; ip_select_ident(iph, &rt->dst, NULL); /* Another hack: avoid icmp_send in ip_fragment */ skb->local_df = 1; ret = IP_VS_XMIT_TUNNEL(skb, cp); if (ret == NF_ACCEPT) ip_local_out(skb); else if (ret == NF_DROP) kfree_skb(skb); LeaveFunction(10); return NF_STOLEN; tx_error_icmp: dst_link_failure(skb); tx_error: kfree_skb(skb); LeaveFunction(10); return NF_STOLEN; tx_error_put: ip_rt_put(rt); goto tx_error; }
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; }
/* * 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; }