diff options
Diffstat (limited to 'src/http/modules/ngx_http_upstream_ip_hash_module.c')
| -rw-r--r-- | src/http/modules/ngx_http_upstream_ip_hash_module.c | 228 |
1 files changed, 228 insertions, 0 deletions
diff --git a/src/http/modules/ngx_http_upstream_ip_hash_module.c b/src/http/modules/ngx_http_upstream_ip_hash_module.c new file mode 100644 index 000000000..1de019e05 --- /dev/null +++ b/src/http/modules/ngx_http_upstream_ip_hash_module.c @@ -0,0 +1,228 @@ + +/* + * Copyright (C) Igor Sysoev + */ + + +#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; + + /* AF_INET only */ + u_char addr[3]; + + 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 +}; + + +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; + 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; + + /* AF_INET only */ + sin = (struct sockaddr_in *) r->connection->sockaddr; + iphp->addr[0] = (u_char) ((sin->sin_addr.s_addr >> 24) & 0xff); + iphp->addr[1] = (u_char) ((sin->sin_addr.s_addr >> 16) & 0xff); + iphp->addr[2] = (u_char) ((sin->sin_addr.s_addr >> 8) & 0xff); + + 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; + 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->number == 1) { + 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 < 3; i++) { + hash = (hash * 113 + iphp->addr[i]) % 6271; + } + + p = hash % iphp->rrp.peers->number; + + n = p / (8 * sizeof(uintptr_t)); + m = 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 (peer->max_fails == 0 || peer->fails < peer->max_fails) { + break; + } + + if (now - peer->accessed > peer->fail_timeout) { + peer->fails = 0; + break; + } + + } else { + 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); + } + } + + pc->sockaddr = peer->sockaddr; + pc->socklen = peer->socklen; + pc->name = &peer->name; +#if (NGX_SSL) + pc->ssl_session = peer->ssl_session; +#endif + + /* 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_MAX_FAILS + |NGX_HTTP_UPSTREAM_FAIL_TIMEOUT + |NGX_HTTP_UPSTREAM_DOWN; + + return NGX_CONF_OK; +} |