/src/http/modules/ngx_http_upstream_ip_hash_module.c
C | 276 lines | 186 code | 81 blank | 9 comment | 23 complexity | 1d95e9c6b8e32b6578d8941f043e73a2 MD5 | raw file
- /*
- * Copyright (C) Igor Sysoev
- * Copyright (C) Nginx, Inc.
- */
- #include <ngx_config.h>
- #include <ngx_core.h>
- #include <ngx_http.h>
- typedef struct {
- /* the round robin data must be first */
- ngx_http_upstream_rr_peer_data_t rrp;
- ngx_uint_t hash;
- u_char addrlen;
- u_char *addr;
- u_char tries;
- ngx_event_get_peer_pt get_rr_peer;
- } ngx_http_upstream_ip_hash_peer_data_t;
- static ngx_int_t ngx_http_upstream_init_ip_hash_peer(ngx_http_request_t *r,
- ngx_http_upstream_srv_conf_t *us);
- static ngx_int_t ngx_http_upstream_get_ip_hash_peer(ngx_peer_connection_t *pc,
- void *data);
- static char *ngx_http_upstream_ip_hash(ngx_conf_t *cf, ngx_command_t *cmd,
- void *conf);
- static ngx_command_t ngx_http_upstream_ip_hash_commands[] = {
- { ngx_string("ip_hash"),
- NGX_HTTP_UPS_CONF|NGX_CONF_NOARGS,
- ngx_http_upstream_ip_hash,
- 0,
- 0,
- NULL },
- ngx_null_command
- };
- static ngx_http_module_t ngx_http_upstream_ip_hash_module_ctx = {
- NULL, /* preconfiguration */
- NULL, /* postconfiguration */
- NULL, /* create main configuration */
- NULL, /* init main configuration */
- NULL, /* create server configuration */
- NULL, /* merge server configuration */
- NULL, /* create location configuration */
- NULL /* merge location configuration */
- };
- ngx_module_t ngx_http_upstream_ip_hash_module = {
- NGX_MODULE_V1,
- &ngx_http_upstream_ip_hash_module_ctx, /* module context */
- ngx_http_upstream_ip_hash_commands, /* module directives */
- NGX_HTTP_MODULE, /* module type */
- NULL, /* init master */
- NULL, /* init module */
- NULL, /* init process */
- NULL, /* init thread */
- NULL, /* exit thread */
- NULL, /* exit process */
- NULL, /* exit master */
- NGX_MODULE_V1_PADDING
- };
- static u_char ngx_http_upstream_ip_hash_pseudo_addr[3];
- static ngx_int_t
- ngx_http_upstream_init_ip_hash(ngx_conf_t *cf, ngx_http_upstream_srv_conf_t *us)
- {
- if (ngx_http_upstream_init_round_robin(cf, us) != NGX_OK) {
- return NGX_ERROR;
- }
- us->peer.init = ngx_http_upstream_init_ip_hash_peer;
- return NGX_OK;
- }
- static ngx_int_t
- ngx_http_upstream_init_ip_hash_peer(ngx_http_request_t *r,
- ngx_http_upstream_srv_conf_t *us)
- {
- struct sockaddr_in *sin;
- #if (NGX_HAVE_INET6)
- struct sockaddr_in6 *sin6;
- #endif
- ngx_http_upstream_ip_hash_peer_data_t *iphp;
- iphp = ngx_palloc(r->pool, sizeof(ngx_http_upstream_ip_hash_peer_data_t));
- if (iphp == NULL) {
- return NGX_ERROR;
- }
- r->upstream->peer.data = &iphp->rrp;
- if (ngx_http_upstream_init_round_robin_peer(r, us) != NGX_OK) {
- return NGX_ERROR;
- }
- r->upstream->peer.get = ngx_http_upstream_get_ip_hash_peer;
- switch (r->connection->sockaddr->sa_family) {
- case AF_INET:
- sin = (struct sockaddr_in *) r->connection->sockaddr;
- iphp->addr = (u_char *) &sin->sin_addr.s_addr;
- iphp->addrlen = 3;
- break;
- #if (NGX_HAVE_INET6)
- case AF_INET6:
- sin6 = (struct sockaddr_in6 *) r->connection->sockaddr;
- iphp->addr = (u_char *) &sin6->sin6_addr.s6_addr;
- iphp->addrlen = 16;
- break;
- #endif
- default:
- iphp->addr = ngx_http_upstream_ip_hash_pseudo_addr;
- iphp->addrlen = 3;
- }
- iphp->hash = 89;
- iphp->tries = 0;
- iphp->get_rr_peer = ngx_http_upstream_get_round_robin_peer;
- return NGX_OK;
- }
- static ngx_int_t
- ngx_http_upstream_get_ip_hash_peer(ngx_peer_connection_t *pc, void *data)
- {
- ngx_http_upstream_ip_hash_peer_data_t *iphp = data;
- time_t now;
- ngx_int_t w;
- uintptr_t m;
- ngx_uint_t i, n, p, hash;
- ngx_http_upstream_rr_peer_t *peer;
- ngx_log_debug1(NGX_LOG_DEBUG_HTTP, pc->log, 0,
- "get ip hash peer, try: %ui", pc->tries);
- /* TODO: cached */
- if (iphp->tries > 20 || iphp->rrp.peers->single) {
- return iphp->get_rr_peer(pc, &iphp->rrp);
- }
- now = ngx_time();
- pc->cached = 0;
- pc->connection = NULL;
- hash = iphp->hash;
- for ( ;; ) {
- for (i = 0; i < iphp->addrlen; i++) {
- hash = (hash * 113 + iphp->addr[i]) % 6271;
- }
- if (!iphp->rrp.peers->weighted) {
- p = hash % iphp->rrp.peers->number;
- } else {
- w = hash % iphp->rrp.peers->total_weight;
- for (i = 0; i < iphp->rrp.peers->number; i++) {
- w -= iphp->rrp.peers->peer[i].weight;
- if (w < 0) {
- break;
- }
- }
- p = i;
- }
- n = p / (8 * sizeof(uintptr_t));
- m = (uintptr_t) 1 << p % (8 * sizeof(uintptr_t));
- if (!(iphp->rrp.tried[n] & m)) {
- ngx_log_debug2(NGX_LOG_DEBUG_HTTP, pc->log, 0,
- "get ip hash peer, hash: %ui %04XA", p, m);
- peer = &iphp->rrp.peers->peer[p];
- /* ngx_lock_mutex(iphp->rrp.peers->mutex); */
- if (!peer->down) {
- #if (NGX_HTTP_UPSTREAM_CHECK)
- ngx_log_debug1(NGX_LOG_DEBUG_HTTP, pc->log, 0,
- "get ip_hash peer, check_index: %ui",
- peer->check_index);
- if (!ngx_http_upstream_check_peer_down(peer->check_index)) {
- #endif
- if (peer->max_fails == 0 || peer->fails < peer->max_fails) {
- break;
- }
- if (now - peer->checked > peer->fail_timeout) {
- peer->checked = now;
- break;
- }
- #if (NGX_HTTP_UPSTREAM_CHECK)
- }
- #endif
- }
- iphp->rrp.tried[n] |= m;
- /* ngx_unlock_mutex(iphp->rrp.peers->mutex); */
- pc->tries--;
- }
- if (++iphp->tries >= 20) {
- return iphp->get_rr_peer(pc, &iphp->rrp);
- }
- }
- iphp->rrp.current = p;
- pc->sockaddr = peer->sockaddr;
- pc->socklen = peer->socklen;
- pc->name = &peer->name;
- /* ngx_unlock_mutex(iphp->rrp.peers->mutex); */
- iphp->rrp.tried[n] |= m;
- iphp->hash = hash;
- return NGX_OK;
- }
- static char *
- ngx_http_upstream_ip_hash(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
- {
- ngx_http_upstream_srv_conf_t *uscf;
- uscf = ngx_http_conf_get_module_srv_conf(cf, ngx_http_upstream_module);
- uscf->peer.init_upstream = ngx_http_upstream_init_ip_hash;
- uscf->flags = NGX_HTTP_UPSTREAM_CREATE
- |NGX_HTTP_UPSTREAM_WEIGHT
- |NGX_HTTP_UPSTREAM_MAX_FAILS
- |NGX_HTTP_UPSTREAM_FAIL_TIMEOUT
- |NGX_HTTP_UPSTREAM_DOWN;
- return NGX_CONF_OK;
- }