| /* |
| * 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 <wensong@linuxvirtualserver.org> |
| * Peter Kese <peter.kese@ijs.si> |
| * Julian Anastasov <ja@ssi.bg> |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License |
| * as published by the Free Software Foundation; either version |
| * 2 of the License, or (at your option) any later version. |
| * |
| * 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. Many code here is taken from IP MASQ code of kernel 2.2. |
| * |
| * Changes: |
| * |
| */ |
| |
| #include <linux/interrupt.h> |
| #include <linux/in.h> |
| #include <linux/net.h> |
| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/vmalloc.h> |
| #include <linux/proc_fs.h> /* for proc_net_* */ |
| #include <linux/seq_file.h> |
| #include <linux/jhash.h> |
| #include <linux/random.h> |
| |
| #include <net/net_namespace.h> |
| #include <net/ip_vs.h> |
| |
| |
| /* |
| * Connection hash table: for input and output packets lookups of IPVS |
| */ |
| static struct list_head *ip_vs_conn_tab; |
| |
| /* SLAB cache for IPVS connections */ |
| static struct kmem_cache *ip_vs_conn_cachep __read_mostly; |
| |
| /* counter for current IPVS connections */ |
| static atomic_t ip_vs_conn_count = ATOMIC_INIT(0); |
| |
| /* counter for no client port connections */ |
| static atomic_t ip_vs_conn_no_cport_cnt = ATOMIC_INIT(0); |
| |
| /* random value for IPVS connection hash */ |
| static unsigned int ip_vs_conn_rnd; |
| |
| /* |
| * Fine locking granularity for big connection hash table |
| */ |
| #define CT_LOCKARRAY_BITS 4 |
| #define CT_LOCKARRAY_SIZE (1<<CT_LOCKARRAY_BITS) |
| #define CT_LOCKARRAY_MASK (CT_LOCKARRAY_SIZE-1) |
| |
| struct ip_vs_aligned_lock |
| { |
| rwlock_t l; |
| } __attribute__((__aligned__(SMP_CACHE_BYTES))); |
| |
| /* lock array for conn table */ |
| static struct ip_vs_aligned_lock |
| __ip_vs_conntbl_lock_array[CT_LOCKARRAY_SIZE] __cacheline_aligned; |
| |
| static inline void ct_read_lock(unsigned key) |
| { |
| read_lock(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l); |
| } |
| |
| static inline void ct_read_unlock(unsigned key) |
| { |
| read_unlock(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l); |
| } |
| |
| static inline void ct_write_lock(unsigned key) |
| { |
| write_lock(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l); |
| } |
| |
| static inline void ct_write_unlock(unsigned key) |
| { |
| write_unlock(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l); |
| } |
| |
| static inline void ct_read_lock_bh(unsigned key) |
| { |
| read_lock_bh(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l); |
| } |
| |
| static inline void ct_read_unlock_bh(unsigned key) |
| { |
| read_unlock_bh(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l); |
| } |
| |
| static inline void ct_write_lock_bh(unsigned key) |
| { |
| write_lock_bh(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l); |
| } |
| |
| static inline void ct_write_unlock_bh(unsigned key) |
| { |
| write_unlock_bh(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l); |
| } |
| |
| |
| /* |
| * Returns hash value for IPVS connection entry |
| */ |
| static unsigned int ip_vs_conn_hashkey(int af, unsigned proto, |
| const union nf_inet_addr *addr, |
| __be16 port) |
| { |
| #ifdef CONFIG_IP_VS_IPV6 |
| if (af == AF_INET6) |
| return jhash_3words(jhash(addr, 16, ip_vs_conn_rnd), |
| (__force u32)port, proto, ip_vs_conn_rnd) |
| & IP_VS_CONN_TAB_MASK; |
| #endif |
| return jhash_3words((__force u32)addr->ip, (__force u32)port, proto, |
| ip_vs_conn_rnd) |
| & IP_VS_CONN_TAB_MASK; |
| } |
| |
| |
| /* |
| * Hashes ip_vs_conn in ip_vs_conn_tab by proto,addr,port. |
| * returns bool success. |
| */ |
| static inline int ip_vs_conn_hash(struct ip_vs_conn *cp) |
| { |
| unsigned hash; |
| int ret; |
| |
| /* Hash by protocol, client address and port */ |
| hash = ip_vs_conn_hashkey(cp->af, cp->protocol, &cp->caddr, cp->cport); |
| |
| ct_write_lock(hash); |
| |
| if (!(cp->flags & IP_VS_CONN_F_HASHED)) { |
| list_add(&cp->c_list, &ip_vs_conn_tab[hash]); |
| cp->flags |= IP_VS_CONN_F_HASHED; |
| atomic_inc(&cp->refcnt); |
| ret = 1; |
| } else { |
| IP_VS_ERR("ip_vs_conn_hash(): request for already hashed, " |
| "called from %p\n", __builtin_return_address(0)); |
| ret = 0; |
| } |
| |
| ct_write_unlock(hash); |
| |
| return ret; |
| } |
| |
| |
| /* |
| * UNhashes ip_vs_conn from ip_vs_conn_tab. |
| * returns bool success. |
| */ |
| static inline int ip_vs_conn_unhash(struct ip_vs_conn *cp) |
| { |
| unsigned hash; |
| int ret; |
| |
| /* unhash it and decrease its reference counter */ |
| hash = ip_vs_conn_hashkey(cp->af, cp->protocol, &cp->caddr, cp->cport); |
| |
| ct_write_lock(hash); |
| |
| if (cp->flags & IP_VS_CONN_F_HASHED) { |
| list_del(&cp->c_list); |
| cp->flags &= ~IP_VS_CONN_F_HASHED; |
| atomic_dec(&cp->refcnt); |
| ret = 1; |
| } else |
| ret = 0; |
| |
| ct_write_unlock(hash); |
| |
| return ret; |
| } |
| |
| |
| /* |
| * Gets ip_vs_conn associated with supplied parameters in the ip_vs_conn_tab. |
| * Called for pkts coming from OUTside-to-INside. |
| * s_addr, s_port: pkt source address (foreign host) |
| * d_addr, d_port: pkt dest address (load balancer) |
| */ |
| static inline struct ip_vs_conn *__ip_vs_conn_in_get |
| (int af, int protocol, const union nf_inet_addr *s_addr, __be16 s_port, |
| const union nf_inet_addr *d_addr, __be16 d_port) |
| { |
| unsigned hash; |
| struct ip_vs_conn *cp; |
| |
| hash = ip_vs_conn_hashkey(af, protocol, s_addr, s_port); |
| |
| ct_read_lock(hash); |
| |
| list_for_each_entry(cp, &ip_vs_conn_tab[hash], c_list) { |
| if (cp->af == af && |
| ip_vs_addr_equal(af, s_addr, &cp->caddr) && |
| ip_vs_addr_equal(af, d_addr, &cp->vaddr) && |
| s_port == cp->cport && d_port == cp->vport && |
| ((!s_port) ^ (!(cp->flags & IP_VS_CONN_F_NO_CPORT))) && |
| protocol == cp->protocol) { |
| /* HIT */ |
| atomic_inc(&cp->refcnt); |
| ct_read_unlock(hash); |
| return cp; |
| } |
| } |
| |
| ct_read_unlock(hash); |
| |
| return NULL; |
| } |
| |
| struct ip_vs_conn *ip_vs_conn_in_get |
| (int af, int protocol, const union nf_inet_addr *s_addr, __be16 s_port, |
| const union nf_inet_addr *d_addr, __be16 d_port) |
| { |
| struct ip_vs_conn *cp; |
| |
| cp = __ip_vs_conn_in_get(af, protocol, s_addr, s_port, d_addr, d_port); |
| if (!cp && atomic_read(&ip_vs_conn_no_cport_cnt)) |
| cp = __ip_vs_conn_in_get(af, protocol, s_addr, 0, d_addr, |
| d_port); |
| |
| IP_VS_DBG_BUF(9, "lookup/in %s %s:%d->%s:%d %s\n", |
| ip_vs_proto_name(protocol), |
| IP_VS_DBG_ADDR(af, s_addr), ntohs(s_port), |
| IP_VS_DBG_ADDR(af, d_addr), ntohs(d_port), |
| cp ? "hit" : "not hit"); |
| |
| return cp; |
| } |
| |
| /* Get reference to connection template */ |
| struct ip_vs_conn *ip_vs_ct_in_get |
| (int af, int protocol, const union nf_inet_addr *s_addr, __be16 s_port, |
| const union nf_inet_addr *d_addr, __be16 d_port) |
| { |
| unsigned hash; |
| struct ip_vs_conn *cp; |
| |
| hash = ip_vs_conn_hashkey(af, protocol, s_addr, s_port); |
| |
| ct_read_lock(hash); |
| |
| list_for_each_entry(cp, &ip_vs_conn_tab[hash], c_list) { |
| if (cp->af == af && |
| ip_vs_addr_equal(af, s_addr, &cp->caddr) && |
| ip_vs_addr_equal(af, d_addr, &cp->vaddr) && |
| s_port == cp->cport && d_port == cp->vport && |
| cp->flags & IP_VS_CONN_F_TEMPLATE && |
| protocol == cp->protocol) { |
| /* HIT */ |
| atomic_inc(&cp->refcnt); |
| goto out; |
| } |
| } |
| cp = NULL; |
| |
| out: |
| ct_read_unlock(hash); |
| |
| IP_VS_DBG_BUF(9, "template lookup/in %s %s:%d->%s:%d %s\n", |
| ip_vs_proto_name(protocol), |
| IP_VS_DBG_ADDR(af, s_addr), ntohs(s_port), |
| IP_VS_DBG_ADDR(af, d_addr), ntohs(d_port), |
| cp ? "hit" : "not hit"); |
| |
| return cp; |
| } |
| |
| /* |
| * Gets ip_vs_conn associated with supplied parameters in the ip_vs_conn_tab. |
| * Called for pkts coming from inside-to-OUTside. |
| * s_addr, s_port: pkt source address (inside host) |
| * d_addr, d_port: pkt dest address (foreign host) |
| */ |
| struct ip_vs_conn *ip_vs_conn_out_get |
| (int af, int protocol, const union nf_inet_addr *s_addr, __be16 s_port, |
| const union nf_inet_addr *d_addr, __be16 d_port) |
| { |
| unsigned hash; |
| struct ip_vs_conn *cp, *ret=NULL; |
| |
| /* |
| * Check for "full" addressed entries |
| */ |
| hash = ip_vs_conn_hashkey(af, protocol, d_addr, d_port); |
| |
| ct_read_lock(hash); |
| |
| list_for_each_entry(cp, &ip_vs_conn_tab[hash], c_list) { |
| if (cp->af == af && |
| ip_vs_addr_equal(af, d_addr, &cp->caddr) && |
| ip_vs_addr_equal(af, s_addr, &cp->daddr) && |
| d_port == cp->cport && s_port == cp->dport && |
| protocol == cp->protocol) { |
| /* HIT */ |
| atomic_inc(&cp->refcnt); |
| ret = cp; |
| break; |
| } |
| } |
| |
| ct_read_unlock(hash); |
| |
| IP_VS_DBG_BUF(9, "lookup/out %s %s:%d->%s:%d %s\n", |
| ip_vs_proto_name(protocol), |
| IP_VS_DBG_ADDR(af, s_addr), ntohs(s_port), |
| IP_VS_DBG_ADDR(af, d_addr), ntohs(d_port), |
| ret ? "hit" : "not hit"); |
| |
| return ret; |
| } |
| |
| |
| /* |
| * Put back the conn and restart its timer with its timeout |
| */ |
| void ip_vs_conn_put(struct ip_vs_conn *cp) |
| { |
| /* reset it expire in its timeout */ |
| mod_timer(&cp->timer, jiffies+cp->timeout); |
| |
| __ip_vs_conn_put(cp); |
| } |
| |
| |
| /* |
| * Fill a no_client_port connection with a client port number |
| */ |
| void ip_vs_conn_fill_cport(struct ip_vs_conn *cp, __be16 cport) |
| { |
| if (ip_vs_conn_unhash(cp)) { |
| spin_lock(&cp->lock); |
| if (cp->flags & IP_VS_CONN_F_NO_CPORT) { |
| atomic_dec(&ip_vs_conn_no_cport_cnt); |
| cp->flags &= ~IP_VS_CONN_F_NO_CPORT; |
| cp->cport = cport; |
| } |
| spin_unlock(&cp->lock); |
| |
| /* hash on new dport */ |
| ip_vs_conn_hash(cp); |
| } |
| } |
| |
| |
| /* |
| * Bind a connection entry with the corresponding packet_xmit. |
| * Called by ip_vs_conn_new. |
| */ |
| static inline void ip_vs_bind_xmit(struct ip_vs_conn *cp) |
| { |
| switch (IP_VS_FWD_METHOD(cp)) { |
| case IP_VS_CONN_F_MASQ: |
| cp->packet_xmit = ip_vs_nat_xmit; |
| break; |
| |
| case IP_VS_CONN_F_TUNNEL: |
| cp->packet_xmit = ip_vs_tunnel_xmit; |
| break; |
| |
| case IP_VS_CONN_F_DROUTE: |
| cp->packet_xmit = ip_vs_dr_xmit; |
| break; |
| |
| case IP_VS_CONN_F_LOCALNODE: |
| cp->packet_xmit = ip_vs_null_xmit; |
| break; |
| |
| case IP_VS_CONN_F_BYPASS: |
| cp->packet_xmit = ip_vs_bypass_xmit; |
| break; |
| } |
| } |
| |
| #ifdef CONFIG_IP_VS_IPV6 |
| static inline void ip_vs_bind_xmit_v6(struct ip_vs_conn *cp) |
| { |
| switch (IP_VS_FWD_METHOD(cp)) { |
| case IP_VS_CONN_F_MASQ: |
| cp->packet_xmit = ip_vs_nat_xmit_v6; |
| break; |
| |
| case IP_VS_CONN_F_TUNNEL: |
| cp->packet_xmit = ip_vs_tunnel_xmit_v6; |
| break; |
| |
| case IP_VS_CONN_F_DROUTE: |
| cp->packet_xmit = ip_vs_dr_xmit_v6; |
| break; |
| |
| case IP_VS_CONN_F_LOCALNODE: |
| cp->packet_xmit = ip_vs_null_xmit; |
| break; |
| |
| case IP_VS_CONN_F_BYPASS: |
| cp->packet_xmit = ip_vs_bypass_xmit_v6; |
| break; |
| } |
| } |
| #endif |
| |
| |
| static inline int ip_vs_dest_totalconns(struct ip_vs_dest *dest) |
| { |
| return atomic_read(&dest->activeconns) |
| + atomic_read(&dest->inactconns); |
| } |
| |
| /* |
| * Bind a connection entry with a virtual service destination |
| * Called just after a new connection entry is created. |
| */ |
| static inline void |
| ip_vs_bind_dest(struct ip_vs_conn *cp, struct ip_vs_dest *dest) |
| { |
| /* if dest is NULL, then return directly */ |
| if (!dest) |
| return; |
| |
| /* Increase the refcnt counter of the dest */ |
| atomic_inc(&dest->refcnt); |
| |
| /* Bind with the destination and its corresponding transmitter */ |
| if ((cp->flags & IP_VS_CONN_F_SYNC) && |
| (!(cp->flags & IP_VS_CONN_F_TEMPLATE))) |
| /* if the connection is not template and is created |
| * by sync, preserve the activity flag. |
| */ |
| cp->flags |= atomic_read(&dest->conn_flags) & |
| (~IP_VS_CONN_F_INACTIVE); |
| else |
| cp->flags |= atomic_read(&dest->conn_flags); |
| cp->dest = dest; |
| |
| IP_VS_DBG_BUF(7, "Bind-dest %s c:%s:%d v:%s:%d " |
| "d:%s:%d fwd:%c s:%u conn->flags:%X conn->refcnt:%d " |
| "dest->refcnt:%d\n", |
| ip_vs_proto_name(cp->protocol), |
| 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), |
| ip_vs_fwd_tag(cp), cp->state, |
| cp->flags, atomic_read(&cp->refcnt), |
| atomic_read(&dest->refcnt)); |
| |
| /* Update the connection counters */ |
| if (!(cp->flags & IP_VS_CONN_F_TEMPLATE)) { |
| /* It is a normal connection, so increase the inactive |
| connection counter because it is in TCP SYNRECV |
| state (inactive) or other protocol inacive state */ |
| if ((cp->flags & IP_VS_CONN_F_SYNC) && |
| (!(cp->flags & IP_VS_CONN_F_INACTIVE))) |
| atomic_inc(&dest->activeconns); |
| else |
| atomic_inc(&dest->inactconns); |
| } else { |
| /* It is a persistent connection/template, so increase |
| the peristent connection counter */ |
| atomic_inc(&dest->persistconns); |
| } |
| |
| if (dest->u_threshold != 0 && |
| ip_vs_dest_totalconns(dest) >= dest->u_threshold) |
| dest->flags |= IP_VS_DEST_F_OVERLOAD; |
| } |
| |
| |
| /* |
| * Check if there is a destination for the connection, if so |
| * bind the connection to the destination. |
| */ |
| struct ip_vs_dest *ip_vs_try_bind_dest(struct ip_vs_conn *cp) |
| { |
| struct ip_vs_dest *dest; |
| |
| if ((cp) && (!cp->dest)) { |
| dest = ip_vs_find_dest(cp->af, &cp->daddr, cp->dport, |
| &cp->vaddr, cp->vport, |
| cp->protocol); |
| ip_vs_bind_dest(cp, dest); |
| return dest; |
| } else |
| return NULL; |
| } |
| |
| |
| /* |
| * Unbind a connection entry with its VS destination |
| * Called by the ip_vs_conn_expire function. |
| */ |
| static inline void ip_vs_unbind_dest(struct ip_vs_conn *cp) |
| { |
| struct ip_vs_dest *dest = cp->dest; |
| |
| if (!dest) |
| return; |
| |
| IP_VS_DBG_BUF(7, "Unbind-dest %s c:%s:%d v:%s:%d " |
| "d:%s:%d fwd:%c s:%u conn->flags:%X conn->refcnt:%d " |
| "dest->refcnt:%d\n", |
| ip_vs_proto_name(cp->protocol), |
| 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), |
| ip_vs_fwd_tag(cp), cp->state, |
| cp->flags, atomic_read(&cp->refcnt), |
| atomic_read(&dest->refcnt)); |
| |
| /* Update the connection counters */ |
| if (!(cp->flags & IP_VS_CONN_F_TEMPLATE)) { |
| /* It is a normal connection, so decrease the inactconns |
| or activeconns counter */ |
| if (cp->flags & IP_VS_CONN_F_INACTIVE) { |
| atomic_dec(&dest->inactconns); |
| } else { |
| atomic_dec(&dest->activeconns); |
| } |
| } else { |
| /* It is a persistent connection/template, so decrease |
| the peristent connection counter */ |
| atomic_dec(&dest->persistconns); |
| } |
| |
| if (dest->l_threshold != 0) { |
| if (ip_vs_dest_totalconns(dest) < dest->l_threshold) |
| dest->flags &= ~IP_VS_DEST_F_OVERLOAD; |
| } else if (dest->u_threshold != 0) { |
| if (ip_vs_dest_totalconns(dest) * 4 < dest->u_threshold * 3) |
| dest->flags &= ~IP_VS_DEST_F_OVERLOAD; |
| } else { |
| if (dest->flags & IP_VS_DEST_F_OVERLOAD) |
| dest->flags &= ~IP_VS_DEST_F_OVERLOAD; |
| } |
| |
| /* |
| * Simply decrease the refcnt of the dest, because the |
| * dest will be either in service's destination list |
| * or in the trash. |
| */ |
| atomic_dec(&dest->refcnt); |
| } |
| |
| |
| /* |
| * Checking if the destination of a connection template is available. |
| * If available, return 1, otherwise invalidate this connection |
| * template and return 0. |
| */ |
| int ip_vs_check_template(struct ip_vs_conn *ct) |
| { |
| struct ip_vs_dest *dest = ct->dest; |
| |
| /* |
| * Checking the dest server status. |
| */ |
| if ((dest == NULL) || |
| !(dest->flags & IP_VS_DEST_F_AVAILABLE) || |
| (sysctl_ip_vs_expire_quiescent_template && |
| (atomic_read(&dest->weight) == 0))) { |
| IP_VS_DBG_BUF(9, "check_template: dest not available for " |
| "protocol %s s:%s:%d v:%s:%d " |
| "-> d:%s:%d\n", |
| ip_vs_proto_name(ct->protocol), |
| IP_VS_DBG_ADDR(ct->af, &ct->caddr), |
| ntohs(ct->cport), |
| IP_VS_DBG_ADDR(ct->af, &ct->vaddr), |
| ntohs(ct->vport), |
| IP_VS_DBG_ADDR(ct->af, &ct->daddr), |
| ntohs(ct->dport)); |
| |
| /* |
| * Invalidate the connection template |
| */ |
| if (ct->vport != htons(0xffff)) { |
| if (ip_vs_conn_unhash(ct)) { |
| ct->dport = htons(0xffff); |
| ct->vport = htons(0xffff); |
| ct->cport = 0; |
| ip_vs_conn_hash(ct); |
| } |
| } |
| |
| /* |
| * Simply decrease the refcnt of the template, |
| * don't restart its timer. |
| */ |
| atomic_dec(&ct->refcnt); |
| return 0; |
| } |
| return 1; |
| } |
| |
| static void ip_vs_conn_expire(unsigned long data) |
| { |
| struct ip_vs_conn *cp = (struct ip_vs_conn *)data; |
| |
| cp->timeout = 60*HZ; |
| |
| /* |
| * hey, I'm using it |
| */ |
| atomic_inc(&cp->refcnt); |
| |
| /* |
| * do I control anybody? |
| */ |
| if (atomic_read(&cp->n_control)) |
| goto expire_later; |
| |
| /* |
| * unhash it if it is hashed in the conn table |
| */ |
| if (!ip_vs_conn_unhash(cp)) |
| goto expire_later; |
| |
| /* |
| * refcnt==1 implies I'm the only one referrer |
| */ |
| if (likely(atomic_read(&cp->refcnt) == 1)) { |
| /* delete the timer if it is activated by other users */ |
| if (timer_pending(&cp->timer)) |
| del_timer(&cp->timer); |
| |
| /* does anybody control me? */ |
| if (cp->control) |
| ip_vs_control_del(cp); |
| |
| if (unlikely(cp->app != NULL)) |
| ip_vs_unbind_app(cp); |
| ip_vs_unbind_dest(cp); |
| if (cp->flags & IP_VS_CONN_F_NO_CPORT) |
| atomic_dec(&ip_vs_conn_no_cport_cnt); |
| atomic_dec(&ip_vs_conn_count); |
| |
| kmem_cache_free(ip_vs_conn_cachep, cp); |
| return; |
| } |
| |
| /* hash it back to the table */ |
| ip_vs_conn_hash(cp); |
| |
| expire_later: |
| IP_VS_DBG(7, "delayed: conn->refcnt-1=%d conn->n_control=%d\n", |
| atomic_read(&cp->refcnt)-1, |
| atomic_read(&cp->n_control)); |
| |
| ip_vs_conn_put(cp); |
| } |
| |
| |
| void ip_vs_conn_expire_now(struct ip_vs_conn *cp) |
| { |
| if (del_timer(&cp->timer)) |
| mod_timer(&cp->timer, jiffies); |
| } |
| |
| |
| /* |
| * Create a new connection entry and hash it into the ip_vs_conn_tab |
| */ |
| struct ip_vs_conn * |
| ip_vs_conn_new(int af, int proto, const union nf_inet_addr *caddr, __be16 cport, |
| const union nf_inet_addr *vaddr, __be16 vport, |
| const union nf_inet_addr *daddr, __be16 dport, unsigned flags, |
| struct ip_vs_dest *dest) |
| { |
| struct ip_vs_conn *cp; |
| struct ip_vs_protocol *pp = ip_vs_proto_get(proto); |
| |
| cp = kmem_cache_zalloc(ip_vs_conn_cachep, GFP_ATOMIC); |
| if (cp == NULL) { |
| IP_VS_ERR_RL("ip_vs_conn_new: no memory available.\n"); |
| return NULL; |
| } |
| |
| INIT_LIST_HEAD(&cp->c_list); |
| setup_timer(&cp->timer, ip_vs_conn_expire, (unsigned long)cp); |
| cp->af = af; |
| cp->protocol = proto; |
| ip_vs_addr_copy(af, &cp->caddr, caddr); |
| cp->cport = cport; |
| ip_vs_addr_copy(af, &cp->vaddr, vaddr); |
| cp->vport = vport; |
| ip_vs_addr_copy(af, &cp->daddr, daddr); |
| cp->dport = dport; |
| cp->flags = flags; |
| spin_lock_init(&cp->lock); |
| |
| /* |
| * Set the entry is referenced by the current thread before hashing |
| * it in the table, so that other thread run ip_vs_random_dropentry |
| * but cannot drop this entry. |
| */ |
| atomic_set(&cp->refcnt, 1); |
| |
| atomic_set(&cp->n_control, 0); |
| atomic_set(&cp->in_pkts, 0); |
| |
| atomic_inc(&ip_vs_conn_count); |
| if (flags & IP_VS_CONN_F_NO_CPORT) |
| atomic_inc(&ip_vs_conn_no_cport_cnt); |
| |
| /* Bind the connection with a destination server */ |
| ip_vs_bind_dest(cp, dest); |
| |
| /* Set its state and timeout */ |
| cp->state = 0; |
| cp->timeout = 3*HZ; |
| |
| /* Bind its packet transmitter */ |
| #ifdef CONFIG_IP_VS_IPV6 |
| if (af == AF_INET6) |
| ip_vs_bind_xmit_v6(cp); |
| else |
| #endif |
| ip_vs_bind_xmit(cp); |
| |
| if (unlikely(pp && atomic_read(&pp->appcnt))) |
| ip_vs_bind_app(cp, pp); |
| |
| /* Hash it in the ip_vs_conn_tab finally */ |
| ip_vs_conn_hash(cp); |
| |
| return cp; |
| } |
| |
| |
| /* |
| * /proc/net/ip_vs_conn entries |
| */ |
| #ifdef CONFIG_PROC_FS |
| |
| static void *ip_vs_conn_array(struct seq_file *seq, loff_t pos) |
| { |
| int idx; |
| struct ip_vs_conn *cp; |
| |
| for(idx = 0; idx < IP_VS_CONN_TAB_SIZE; idx++) { |
| ct_read_lock_bh(idx); |
| list_for_each_entry(cp, &ip_vs_conn_tab[idx], c_list) { |
| if (pos-- == 0) { |
| seq->private = &ip_vs_conn_tab[idx]; |
| return cp; |
| } |
| } |
| ct_read_unlock_bh(idx); |
| } |
| |
| return NULL; |
| } |
| |
| static void *ip_vs_conn_seq_start(struct seq_file *seq, loff_t *pos) |
| { |
| seq->private = NULL; |
| return *pos ? ip_vs_conn_array(seq, *pos - 1) :SEQ_START_TOKEN; |
| } |
| |
| static void *ip_vs_conn_seq_next(struct seq_file *seq, void *v, loff_t *pos) |
| { |
| struct ip_vs_conn *cp = v; |
| struct list_head *e, *l = seq->private; |
| int idx; |
| |
| ++*pos; |
| if (v == SEQ_START_TOKEN) |
| return ip_vs_conn_array(seq, 0); |
| |
| /* more on same hash chain? */ |
| if ((e = cp->c_list.next) != l) |
| return list_entry(e, struct ip_vs_conn, c_list); |
| |
| idx = l - ip_vs_conn_tab; |
| ct_read_unlock_bh(idx); |
| |
| while (++idx < IP_VS_CONN_TAB_SIZE) { |
| ct_read_lock_bh(idx); |
| list_for_each_entry(cp, &ip_vs_conn_tab[idx], c_list) { |
| seq->private = &ip_vs_conn_tab[idx]; |
| return cp; |
| } |
| ct_read_unlock_bh(idx); |
| } |
| seq->private = NULL; |
| return NULL; |
| } |
| |
| static void ip_vs_conn_seq_stop(struct seq_file *seq, void *v) |
| { |
| struct list_head *l = seq->private; |
| |
| if (l) |
| ct_read_unlock_bh(l - ip_vs_conn_tab); |
| } |
| |
| static int ip_vs_conn_seq_show(struct seq_file *seq, void *v) |
| { |
| |
| if (v == SEQ_START_TOKEN) |
| seq_puts(seq, |
| "Pro FromIP FPrt ToIP TPrt DestIP DPrt State Expires\n"); |
| else { |
| const struct ip_vs_conn *cp = v; |
| |
| #ifdef CONFIG_IP_VS_IPV6 |
| if (cp->af == AF_INET6) |
| seq_printf(seq, |
| "%-3s " NIP6_FMT " %04X " NIP6_FMT |
| " %04X " NIP6_FMT " %04X %-11s %7lu\n", |
| ip_vs_proto_name(cp->protocol), |
| NIP6(cp->caddr.in6), ntohs(cp->cport), |
| NIP6(cp->vaddr.in6), ntohs(cp->vport), |
| NIP6(cp->daddr.in6), ntohs(cp->dport), |
| ip_vs_state_name(cp->protocol, cp->state), |
| (cp->timer.expires-jiffies)/HZ); |
| else |
| #endif |
| seq_printf(seq, |
| "%-3s %08X %04X %08X %04X" |
| " %08X %04X %-11s %7lu\n", |
| ip_vs_proto_name(cp->protocol), |
| ntohl(cp->caddr.ip), ntohs(cp->cport), |
| ntohl(cp->vaddr.ip), ntohs(cp->vport), |
| ntohl(cp->daddr.ip), ntohs(cp->dport), |
| ip_vs_state_name(cp->protocol, cp->state), |
| (cp->timer.expires-jiffies)/HZ); |
| } |
| return 0; |
| } |
| |
| static const struct seq_operations ip_vs_conn_seq_ops = { |
| .start = ip_vs_conn_seq_start, |
| .next = ip_vs_conn_seq_next, |
| .stop = ip_vs_conn_seq_stop, |
| .show = ip_vs_conn_seq_show, |
| }; |
| |
| static int ip_vs_conn_open(struct inode *inode, struct file *file) |
| { |
| return seq_open(file, &ip_vs_conn_seq_ops); |
| } |
| |
| static const struct file_operations ip_vs_conn_fops = { |
| .owner = THIS_MODULE, |
| .open = ip_vs_conn_open, |
| .read = seq_read, |
| .llseek = seq_lseek, |
| .release = seq_release, |
| }; |
| |
| static const char *ip_vs_origin_name(unsigned flags) |
| { |
| if (flags & IP_VS_CONN_F_SYNC) |
| return "SYNC"; |
| else |
| return "LOCAL"; |
| } |
| |
| static int ip_vs_conn_sync_seq_show(struct seq_file *seq, void *v) |
| { |
| |
| if (v == SEQ_START_TOKEN) |
| seq_puts(seq, |
| "Pro FromIP FPrt ToIP TPrt DestIP DPrt State Origin Expires\n"); |
| else { |
| const struct ip_vs_conn *cp = v; |
| |
| #ifdef CONFIG_IP_VS_IPV6 |
| if (cp->af == AF_INET6) |
| seq_printf(seq, |
| "%-3s " NIP6_FMT " %04X " NIP6_FMT |
| " %04X " NIP6_FMT " %04X %-11s %-6s %7lu\n", |
| ip_vs_proto_name(cp->protocol), |
| NIP6(cp->caddr.in6), ntohs(cp->cport), |
| NIP6(cp->vaddr.in6), ntohs(cp->vport), |
| NIP6(cp->daddr.in6), ntohs(cp->dport), |
| ip_vs_state_name(cp->protocol, cp->state), |
| ip_vs_origin_name(cp->flags), |
| (cp->timer.expires-jiffies)/HZ); |
| else |
| #endif |
| seq_printf(seq, |
| "%-3s %08X %04X %08X %04X " |
| "%08X %04X %-11s %-6s %7lu\n", |
| ip_vs_proto_name(cp->protocol), |
| ntohl(cp->caddr.ip), ntohs(cp->cport), |
| ntohl(cp->vaddr.ip), ntohs(cp->vport), |
| ntohl(cp->daddr.ip), ntohs(cp->dport), |
| ip_vs_state_name(cp->protocol, cp->state), |
| ip_vs_origin_name(cp->flags), |
| (cp->timer.expires-jiffies)/HZ); |
| } |
| return 0; |
| } |
| |
| static const struct seq_operations ip_vs_conn_sync_seq_ops = { |
| .start = ip_vs_conn_seq_start, |
| .next = ip_vs_conn_seq_next, |
| .stop = ip_vs_conn_seq_stop, |
| .show = ip_vs_conn_sync_seq_show, |
| }; |
| |
| static int ip_vs_conn_sync_open(struct inode *inode, struct file *file) |
| { |
| return seq_open(file, &ip_vs_conn_sync_seq_ops); |
| } |
| |
| static const struct file_operations ip_vs_conn_sync_fops = { |
| .owner = THIS_MODULE, |
| .open = ip_vs_conn_sync_open, |
| .read = seq_read, |
| .llseek = seq_lseek, |
| .release = seq_release, |
| }; |
| |
| #endif |
| |
| |
| /* |
| * Randomly drop connection entries before running out of memory |
| */ |
| static inline int todrop_entry(struct ip_vs_conn *cp) |
| { |
| /* |
| * The drop rate array needs tuning for real environments. |
| * Called from timer bh only => no locking |
| */ |
| static const char todrop_rate[9] = {0, 1, 2, 3, 4, 5, 6, 7, 8}; |
| static char todrop_counter[9] = {0}; |
| int i; |
| |
| /* if the conn entry hasn't lasted for 60 seconds, don't drop it. |
| This will leave enough time for normal connection to get |
| through. */ |
| if (time_before(cp->timeout + jiffies, cp->timer.expires + 60*HZ)) |
| return 0; |
| |
| /* Don't drop the entry if its number of incoming packets is not |
| located in [0, 8] */ |
| i = atomic_read(&cp->in_pkts); |
| if (i > 8 || i < 0) return 0; |
| |
| if (!todrop_rate[i]) return 0; |
| if (--todrop_counter[i] > 0) return 0; |
| |
| todrop_counter[i] = todrop_rate[i]; |
| return 1; |
| } |
| |
| /* Called from keventd and must protect itself from softirqs */ |
| void ip_vs_random_dropentry(void) |
| { |
| int idx; |
| struct ip_vs_conn *cp; |
| |
| /* |
| * Randomly scan 1/32 of the whole table every second |
| */ |
| for (idx = 0; idx < (IP_VS_CONN_TAB_SIZE>>5); idx++) { |
| unsigned hash = net_random() & IP_VS_CONN_TAB_MASK; |
| |
| /* |
| * Lock is actually needed in this loop. |
| */ |
| ct_write_lock_bh(hash); |
| |
| list_for_each_entry(cp, &ip_vs_conn_tab[hash], c_list) { |
| if (cp->flags & IP_VS_CONN_F_TEMPLATE) |
| /* connection template */ |
| continue; |
| |
| if (cp->protocol == IPPROTO_TCP) { |
| switch(cp->state) { |
| case IP_VS_TCP_S_SYN_RECV: |
| case IP_VS_TCP_S_SYNACK: |
| break; |
| |
| case IP_VS_TCP_S_ESTABLISHED: |
| if (todrop_entry(cp)) |
| break; |
| continue; |
| |
| default: |
| continue; |
| } |
| } else { |
| if (!todrop_entry(cp)) |
| continue; |
| } |
| |
| IP_VS_DBG(4, "del connection\n"); |
| ip_vs_conn_expire_now(cp); |
| if (cp->control) { |
| IP_VS_DBG(4, "del conn template\n"); |
| ip_vs_conn_expire_now(cp->control); |
| } |
| } |
| ct_write_unlock_bh(hash); |
| } |
| } |
| |
| |
| /* |
| * Flush all the connection entries in the ip_vs_conn_tab |
| */ |
| static void ip_vs_conn_flush(void) |
| { |
| int idx; |
| struct ip_vs_conn *cp; |
| |
| flush_again: |
| for (idx=0; idx<IP_VS_CONN_TAB_SIZE; idx++) { |
| /* |
| * Lock is actually needed in this loop. |
| */ |
| ct_write_lock_bh(idx); |
| |
| list_for_each_entry(cp, &ip_vs_conn_tab[idx], c_list) { |
| |
| IP_VS_DBG(4, "del connection\n"); |
| ip_vs_conn_expire_now(cp); |
| if (cp->control) { |
| IP_VS_DBG(4, "del conn template\n"); |
| ip_vs_conn_expire_now(cp->control); |
| } |
| } |
| ct_write_unlock_bh(idx); |
| } |
| |
| /* the counter may be not NULL, because maybe some conn entries |
| are run by slow timer handler or unhashed but still referred */ |
| if (atomic_read(&ip_vs_conn_count) != 0) { |
| schedule(); |
| goto flush_again; |
| } |
| } |
| |
| |
| int __init ip_vs_conn_init(void) |
| { |
| int idx; |
| |
| /* |
| * Allocate the connection hash table and initialize its list heads |
| */ |
| ip_vs_conn_tab = vmalloc(IP_VS_CONN_TAB_SIZE*sizeof(struct list_head)); |
| if (!ip_vs_conn_tab) |
| return -ENOMEM; |
| |
| /* Allocate ip_vs_conn slab cache */ |
| ip_vs_conn_cachep = kmem_cache_create("ip_vs_conn", |
| sizeof(struct ip_vs_conn), 0, |
| SLAB_HWCACHE_ALIGN, NULL); |
| if (!ip_vs_conn_cachep) { |
| vfree(ip_vs_conn_tab); |
| return -ENOMEM; |
| } |
| |
| IP_VS_INFO("Connection hash table configured " |
| "(size=%d, memory=%ldKbytes)\n", |
| IP_VS_CONN_TAB_SIZE, |
| (long)(IP_VS_CONN_TAB_SIZE*sizeof(struct list_head))/1024); |
| IP_VS_DBG(0, "Each connection entry needs %Zd bytes at least\n", |
| sizeof(struct ip_vs_conn)); |
| |
| for (idx = 0; idx < IP_VS_CONN_TAB_SIZE; idx++) { |
| INIT_LIST_HEAD(&ip_vs_conn_tab[idx]); |
| } |
| |
| for (idx = 0; idx < CT_LOCKARRAY_SIZE; idx++) { |
| rwlock_init(&__ip_vs_conntbl_lock_array[idx].l); |
| } |
| |
| proc_net_fops_create(&init_net, "ip_vs_conn", 0, &ip_vs_conn_fops); |
| proc_net_fops_create(&init_net, "ip_vs_conn_sync", 0, &ip_vs_conn_sync_fops); |
| |
| /* calculate the random value for connection hash */ |
| get_random_bytes(&ip_vs_conn_rnd, sizeof(ip_vs_conn_rnd)); |
| |
| return 0; |
| } |
| |
| |
| void ip_vs_conn_cleanup(void) |
| { |
| /* flush all the connection entries first */ |
| ip_vs_conn_flush(); |
| |
| /* Release the empty cache */ |
| kmem_cache_destroy(ip_vs_conn_cachep); |
| proc_net_remove(&init_net, "ip_vs_conn"); |
| proc_net_remove(&init_net, "ip_vs_conn_sync"); |
| vfree(ip_vs_conn_tab); |
| } |