Mercurial > hg > nginx-quic
view src/http/modules/ngx_http_upstream_random_module.c @ 7401:a7ff19afbb14
Negative size buffers detection.
In the past, there were several security issues which resulted in
worker process memory disclosure due to buffers with negative size.
It looks reasonable to check for such buffers in various places,
much like we already check for zero size buffers.
While here, removed "#if 1 / #endif" around zero size buffer checks.
It looks highly unlikely that we'll disable these checks anytime soon.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Mon, 26 Nov 2018 18:29:56 +0300 |
parents | f2396ecf608b |
children |
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/* * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_http.h> typedef struct { ngx_http_upstream_rr_peer_t *peer; ngx_uint_t range; } ngx_http_upstream_random_range_t; typedef struct { ngx_uint_t two; ngx_http_upstream_random_range_t *ranges; } ngx_http_upstream_random_srv_conf_t; typedef struct { /* the round robin data must be first */ ngx_http_upstream_rr_peer_data_t rrp; ngx_http_upstream_random_srv_conf_t *conf; u_char tries; } ngx_http_upstream_random_peer_data_t; static ngx_int_t ngx_http_upstream_init_random(ngx_conf_t *cf, ngx_http_upstream_srv_conf_t *us); static ngx_int_t ngx_http_upstream_update_random(ngx_pool_t *pool, ngx_http_upstream_srv_conf_t *us); static ngx_int_t ngx_http_upstream_init_random_peer(ngx_http_request_t *r, ngx_http_upstream_srv_conf_t *us); static ngx_int_t ngx_http_upstream_get_random_peer(ngx_peer_connection_t *pc, void *data); static ngx_int_t ngx_http_upstream_get_random2_peer(ngx_peer_connection_t *pc, void *data); static ngx_uint_t ngx_http_upstream_peek_random_peer( ngx_http_upstream_rr_peers_t *peers, ngx_http_upstream_random_peer_data_t *rp); static void *ngx_http_upstream_random_create_conf(ngx_conf_t *cf); static char *ngx_http_upstream_random(ngx_conf_t *cf, ngx_command_t *cmd, void *conf); static ngx_command_t ngx_http_upstream_random_commands[] = { { ngx_string("random"), NGX_HTTP_UPS_CONF|NGX_CONF_NOARGS|NGX_CONF_TAKE12, ngx_http_upstream_random, NGX_HTTP_SRV_CONF_OFFSET, 0, NULL }, ngx_null_command }; static ngx_http_module_t ngx_http_upstream_random_module_ctx = { NULL, /* preconfiguration */ NULL, /* postconfiguration */ NULL, /* create main configuration */ NULL, /* init main configuration */ ngx_http_upstream_random_create_conf, /* create server configuration */ NULL, /* merge server configuration */ NULL, /* create location configuration */ NULL /* merge location configuration */ }; ngx_module_t ngx_http_upstream_random_module = { NGX_MODULE_V1, &ngx_http_upstream_random_module_ctx, /* module context */ ngx_http_upstream_random_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 ngx_int_t ngx_http_upstream_init_random(ngx_conf_t *cf, ngx_http_upstream_srv_conf_t *us) { ngx_log_debug0(NGX_LOG_DEBUG_HTTP, cf->log, 0, "init random"); if (ngx_http_upstream_init_round_robin(cf, us) != NGX_OK) { return NGX_ERROR; } us->peer.init = ngx_http_upstream_init_random_peer; #if (NGX_HTTP_UPSTREAM_ZONE) if (us->shm_zone) { return NGX_OK; } #endif return ngx_http_upstream_update_random(cf->pool, us); } static ngx_int_t ngx_http_upstream_update_random(ngx_pool_t *pool, ngx_http_upstream_srv_conf_t *us) { size_t size; ngx_uint_t i, total_weight; ngx_http_upstream_rr_peer_t *peer; ngx_http_upstream_rr_peers_t *peers; ngx_http_upstream_random_range_t *ranges; ngx_http_upstream_random_srv_conf_t *rcf; rcf = ngx_http_conf_upstream_srv_conf(us, ngx_http_upstream_random_module); peers = us->peer.data; size = peers->number * sizeof(ngx_http_upstream_random_range_t); ranges = pool ? ngx_palloc(pool, size) : ngx_alloc(size, ngx_cycle->log); if (ranges == NULL) { return NGX_ERROR; } total_weight = 0; for (peer = peers->peer, i = 0; peer; peer = peer->next, i++) { ranges[i].peer = peer; ranges[i].range = total_weight; total_weight += peer->weight; } rcf->ranges = ranges; return NGX_OK; } static ngx_int_t ngx_http_upstream_init_random_peer(ngx_http_request_t *r, ngx_http_upstream_srv_conf_t *us) { ngx_http_upstream_random_srv_conf_t *rcf; ngx_http_upstream_random_peer_data_t *rp; ngx_log_debug0(NGX_LOG_DEBUG_HTTP, r->connection->log, 0, "init random peer"); rcf = ngx_http_conf_upstream_srv_conf(us, ngx_http_upstream_random_module); rp = ngx_palloc(r->pool, sizeof(ngx_http_upstream_random_peer_data_t)); if (rp == NULL) { return NGX_ERROR; } r->upstream->peer.data = &rp->rrp; if (ngx_http_upstream_init_round_robin_peer(r, us) != NGX_OK) { return NGX_ERROR; } if (rcf->two) { r->upstream->peer.get = ngx_http_upstream_get_random2_peer; } else { r->upstream->peer.get = ngx_http_upstream_get_random_peer; } rp->conf = rcf; rp->tries = 0; ngx_http_upstream_rr_peers_rlock(rp->rrp.peers); #if (NGX_HTTP_UPSTREAM_ZONE) if (rp->rrp.peers->shpool && rcf->ranges == NULL) { if (ngx_http_upstream_update_random(NULL, us) != NGX_OK) { ngx_http_upstream_rr_peers_unlock(rp->rrp.peers); return NGX_ERROR; } } #endif ngx_http_upstream_rr_peers_unlock(rp->rrp.peers); return NGX_OK; } static ngx_int_t ngx_http_upstream_get_random_peer(ngx_peer_connection_t *pc, void *data) { ngx_http_upstream_random_peer_data_t *rp = data; time_t now; uintptr_t m; ngx_uint_t i, n; ngx_http_upstream_rr_peer_t *peer; ngx_http_upstream_rr_peers_t *peers; ngx_http_upstream_rr_peer_data_t *rrp; ngx_log_debug1(NGX_LOG_DEBUG_HTTP, pc->log, 0, "get random peer, try: %ui", pc->tries); rrp = &rp->rrp; peers = rrp->peers; ngx_http_upstream_rr_peers_rlock(peers); if (rp->tries > 20 || peers->single) { ngx_http_upstream_rr_peers_unlock(peers); return ngx_http_upstream_get_round_robin_peer(pc, rrp); } pc->cached = 0; pc->connection = NULL; now = ngx_time(); for ( ;; ) { i = ngx_http_upstream_peek_random_peer(peers, rp); peer = rp->conf->ranges[i].peer; n = i / (8 * sizeof(uintptr_t)); m = (uintptr_t) 1 << i % (8 * sizeof(uintptr_t)); if (rrp->tried[n] & m) { goto next; } ngx_http_upstream_rr_peer_lock(peers, peer); if (peer->down) { ngx_http_upstream_rr_peer_unlock(peers, peer); goto next; } if (peer->max_fails && peer->fails >= peer->max_fails && now - peer->checked <= peer->fail_timeout) { ngx_http_upstream_rr_peer_unlock(peers, peer); goto next; } if (peer->max_conns && peer->conns >= peer->max_conns) { ngx_http_upstream_rr_peer_unlock(peers, peer); goto next; } break; next: if (++rp->tries > 20) { ngx_http_upstream_rr_peers_unlock(peers); return ngx_http_upstream_get_round_robin_peer(pc, rrp); } } rrp->current = peer; if (now - peer->checked > peer->fail_timeout) { peer->checked = now; } pc->sockaddr = peer->sockaddr; pc->socklen = peer->socklen; pc->name = &peer->name; peer->conns++; ngx_http_upstream_rr_peer_unlock(peers, peer); ngx_http_upstream_rr_peers_unlock(peers); rrp->tried[n] |= m; return NGX_OK; } static ngx_int_t ngx_http_upstream_get_random2_peer(ngx_peer_connection_t *pc, void *data) { ngx_http_upstream_random_peer_data_t *rp = data; time_t now; uintptr_t m; ngx_uint_t i, n, p; ngx_http_upstream_rr_peer_t *peer, *prev; ngx_http_upstream_rr_peers_t *peers; ngx_http_upstream_rr_peer_data_t *rrp; ngx_log_debug1(NGX_LOG_DEBUG_HTTP, pc->log, 0, "get random2 peer, try: %ui", pc->tries); rrp = &rp->rrp; peers = rrp->peers; ngx_http_upstream_rr_peers_wlock(peers); if (rp->tries > 20 || peers->single) { ngx_http_upstream_rr_peers_unlock(peers); return ngx_http_upstream_get_round_robin_peer(pc, rrp); } pc->cached = 0; pc->connection = NULL; now = ngx_time(); prev = NULL; #if (NGX_SUPPRESS_WARN) p = 0; #endif for ( ;; ) { i = ngx_http_upstream_peek_random_peer(peers, rp); peer = rp->conf->ranges[i].peer; if (peer == prev) { goto next; } n = i / (8 * sizeof(uintptr_t)); m = (uintptr_t) 1 << i % (8 * sizeof(uintptr_t)); if (rrp->tried[n] & m) { goto next; } if (peer->down) { goto next; } if (peer->max_fails && peer->fails >= peer->max_fails && now - peer->checked <= peer->fail_timeout) { goto next; } if (peer->max_conns && peer->conns >= peer->max_conns) { goto next; } if (prev) { if (peer->conns * prev->weight > prev->conns * peer->weight) { peer = prev; n = p / (8 * sizeof(uintptr_t)); m = (uintptr_t) 1 << p % (8 * sizeof(uintptr_t)); } break; } prev = peer; p = i; next: if (++rp->tries > 20) { ngx_http_upstream_rr_peers_unlock(peers); return ngx_http_upstream_get_round_robin_peer(pc, rrp); } } rrp->current = peer; if (now - peer->checked > peer->fail_timeout) { peer->checked = now; } pc->sockaddr = peer->sockaddr; pc->socklen = peer->socklen; pc->name = &peer->name; peer->conns++; ngx_http_upstream_rr_peers_unlock(peers); rrp->tried[n] |= m; return NGX_OK; } static ngx_uint_t ngx_http_upstream_peek_random_peer(ngx_http_upstream_rr_peers_t *peers, ngx_http_upstream_random_peer_data_t *rp) { ngx_uint_t i, j, k, x; x = ngx_random() % peers->total_weight; i = 0; j = peers->number; while (j - i > 1) { k = (i + j) / 2; if (x < rp->conf->ranges[k].range) { j = k; } else { i = k; } } return i; } static void * ngx_http_upstream_random_create_conf(ngx_conf_t *cf) { ngx_http_upstream_random_srv_conf_t *conf; conf = ngx_pcalloc(cf->pool, sizeof(ngx_http_upstream_random_srv_conf_t)); if (conf == NULL) { return NULL; } /* * set by ngx_pcalloc(): * * conf->two = 0; */ return conf; } static char * ngx_http_upstream_random(ngx_conf_t *cf, ngx_command_t *cmd, void *conf) { ngx_http_upstream_random_srv_conf_t *rcf = conf; ngx_str_t *value; ngx_http_upstream_srv_conf_t *uscf; uscf = ngx_http_conf_get_module_srv_conf(cf, ngx_http_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_http_upstream_init_random; uscf->flags = NGX_HTTP_UPSTREAM_CREATE |NGX_HTTP_UPSTREAM_WEIGHT |NGX_HTTP_UPSTREAM_MAX_CONNS |NGX_HTTP_UPSTREAM_MAX_FAILS |NGX_HTTP_UPSTREAM_FAIL_TIMEOUT |NGX_HTTP_UPSTREAM_DOWN; if (cf->args->nelts == 1) { return NGX_CONF_OK; } value = cf->args->elts; if (ngx_strcmp(value[1].data, "two") == 0) { rcf->two = 1; } else { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "invalid parameter \"%V\"", &value[1]); return NGX_CONF_ERROR; } if (cf->args->nelts == 2) { return NGX_CONF_OK; } if (ngx_strcmp(value[2].data, "least_conn") != 0) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "invalid parameter \"%V\"", &value[2]); return NGX_CONF_ERROR; } return NGX_CONF_OK; }