Mercurial > hg > nginx-quic
view src/stream/ngx_stream_upstream_least_conn_module.c @ 8472:aa5f8825f24d
Resolver: fixed label types handling in ngx_resolver_copy().
Previously, anything with any of the two high bits set were interpreted
as compression pointers. This is incorrect, as RFC 1035 clearly states
that "The 10 and 01 combinations are reserved for future use". Further,
the 01 combination is actually allocated for EDNS extended label type
(see RFC 2671 and RFC 6891), not really used though.
Fix is to reject unrecognized label types rather than misinterpreting
them as compression pointers.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Tue, 25 May 2021 15:17:41 +0300 |
parents | 29bf0dbc0a77 |
children |
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/* * Copyright (C) Maxim Dounin * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_stream.h> static ngx_int_t ngx_stream_upstream_init_least_conn_peer( ngx_stream_session_t *s, ngx_stream_upstream_srv_conf_t *us); static ngx_int_t ngx_stream_upstream_get_least_conn_peer( ngx_peer_connection_t *pc, void *data); static char *ngx_stream_upstream_least_conn(ngx_conf_t *cf, ngx_command_t *cmd, void *conf); static ngx_command_t ngx_stream_upstream_least_conn_commands[] = { { ngx_string("least_conn"), NGX_STREAM_UPS_CONF|NGX_CONF_NOARGS, ngx_stream_upstream_least_conn, 0, 0, NULL }, ngx_null_command }; static ngx_stream_module_t ngx_stream_upstream_least_conn_module_ctx = { NULL, /* preconfiguration */ NULL, /* postconfiguration */ NULL, /* create main configuration */ NULL, /* init main configuration */ NULL, /* create server configuration */ NULL /* merge server configuration */ }; ngx_module_t ngx_stream_upstream_least_conn_module = { NGX_MODULE_V1, &ngx_stream_upstream_least_conn_module_ctx, /* module context */ ngx_stream_upstream_least_conn_commands, /* module directives */ NGX_STREAM_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 ngx_int_t ngx_stream_upstream_init_least_conn(ngx_conf_t *cf, ngx_stream_upstream_srv_conf_t *us) { ngx_log_debug0(NGX_LOG_DEBUG_STREAM, cf->log, 0, "init least conn"); if (ngx_stream_upstream_init_round_robin(cf, us) != NGX_OK) { return NGX_ERROR; } us->peer.init = ngx_stream_upstream_init_least_conn_peer; return NGX_OK; } static ngx_int_t ngx_stream_upstream_init_least_conn_peer(ngx_stream_session_t *s, ngx_stream_upstream_srv_conf_t *us) { ngx_log_debug0(NGX_LOG_DEBUG_STREAM, s->connection->log, 0, "init least conn peer"); if (ngx_stream_upstream_init_round_robin_peer(s, us) != NGX_OK) { return NGX_ERROR; } s->upstream->peer.get = ngx_stream_upstream_get_least_conn_peer; return NGX_OK; } static ngx_int_t ngx_stream_upstream_get_least_conn_peer(ngx_peer_connection_t *pc, void *data) { ngx_stream_upstream_rr_peer_data_t *rrp = data; time_t now; uintptr_t m; ngx_int_t rc, total; ngx_uint_t i, n, p, many; ngx_stream_upstream_rr_peer_t *peer, *best; ngx_stream_upstream_rr_peers_t *peers; ngx_log_debug1(NGX_LOG_DEBUG_STREAM, pc->log, 0, "get least conn peer, try: %ui", pc->tries); if (rrp->peers->single) { return ngx_stream_upstream_get_round_robin_peer(pc, rrp); } pc->connection = NULL; now = ngx_time(); peers = rrp->peers; ngx_stream_upstream_rr_peers_wlock(peers); best = NULL; total = 0; #if (NGX_SUPPRESS_WARN) many = 0; p = 0; #endif for (peer = peers->peer, i = 0; peer; peer = peer->next, i++) { n = i / (8 * sizeof(uintptr_t)); m = (uintptr_t) 1 << i % (8 * sizeof(uintptr_t)); if (rrp->tried[n] & m) { continue; } if (peer->down) { continue; } if (peer->max_fails && peer->fails >= peer->max_fails && now - peer->checked <= peer->fail_timeout) { continue; } if (peer->max_conns && peer->conns >= peer->max_conns) { continue; } /* * select peer with least number of connections; if there are * multiple peers with the same number of connections, select * based on round-robin */ if (best == NULL || peer->conns * best->weight < best->conns * peer->weight) { best = peer; many = 0; p = i; } else if (peer->conns * best->weight == best->conns * peer->weight) { many = 1; } } if (best == NULL) { ngx_log_debug0(NGX_LOG_DEBUG_STREAM, pc->log, 0, "get least conn peer, no peer found"); goto failed; } if (many) { ngx_log_debug0(NGX_LOG_DEBUG_STREAM, pc->log, 0, "get least conn peer, many"); for (peer = best, i = p; peer; peer = peer->next, i++) { n = i / (8 * sizeof(uintptr_t)); m = (uintptr_t) 1 << i % (8 * sizeof(uintptr_t)); if (rrp->tried[n] & m) { continue; } if (peer->down) { continue; } if (peer->conns * best->weight != best->conns * peer->weight) { continue; } if (peer->max_fails && peer->fails >= peer->max_fails && now - peer->checked <= peer->fail_timeout) { continue; } if (peer->max_conns && peer->conns >= peer->max_conns) { continue; } peer->current_weight += peer->effective_weight; total += peer->effective_weight; if (peer->effective_weight < peer->weight) { peer->effective_weight++; } if (peer->current_weight > best->current_weight) { best = peer; p = i; } } } best->current_weight -= total; if (now - best->checked > best->fail_timeout) { best->checked = now; } pc->sockaddr = best->sockaddr; pc->socklen = best->socklen; pc->name = &best->name; best->conns++; rrp->current = best; n = p / (8 * sizeof(uintptr_t)); m = (uintptr_t) 1 << p % (8 * sizeof(uintptr_t)); rrp->tried[n] |= m; ngx_stream_upstream_rr_peers_unlock(peers); return NGX_OK; failed: if (peers->next) { ngx_log_debug0(NGX_LOG_DEBUG_STREAM, pc->log, 0, "get least conn peer, backup servers"); rrp->peers = peers->next; n = (rrp->peers->number + (8 * sizeof(uintptr_t) - 1)) / (8 * sizeof(uintptr_t)); for (i = 0; i < n; i++) { rrp->tried[i] = 0; } ngx_stream_upstream_rr_peers_unlock(peers); rc = ngx_stream_upstream_get_least_conn_peer(pc, rrp); if (rc != NGX_BUSY) { return rc; } ngx_stream_upstream_rr_peers_wlock(peers); } ngx_stream_upstream_rr_peers_unlock(peers); pc->name = peers->name; return NGX_BUSY; } static char * ngx_stream_upstream_least_conn(ngx_conf_t *cf, ngx_command_t *cmd, void *conf) { ngx_stream_upstream_srv_conf_t *uscf; uscf = ngx_stream_conf_get_module_srv_conf(cf, ngx_stream_upstream_module); if (uscf->peer.init_upstream) { ngx_conf_log_error(NGX_LOG_WARN, cf, 0, "load balancing method redefined"); } uscf->peer.init_upstream = ngx_stream_upstream_init_least_conn; uscf->flags = NGX_STREAM_UPSTREAM_CREATE |NGX_STREAM_UPSTREAM_WEIGHT |NGX_STREAM_UPSTREAM_MAX_CONNS |NGX_STREAM_UPSTREAM_MAX_FAILS |NGX_STREAM_UPSTREAM_FAIL_TIMEOUT |NGX_STREAM_UPSTREAM_DOWN |NGX_STREAM_UPSTREAM_BACKUP; return NGX_CONF_OK; }