Mercurial > hg > nginx
view src/stream/ngx_stream_limit_conn_module.c @ 7524:deebe988cbd7
Perl: reworked perl module to pass ctx instead of request.
This ensures that correct ctx is always available, including after
filter finalization. In particular, this fixes a segmentation fault
with the following configuration:
location / {
image_filter test;
perl 'sub {
my $r = shift;
$r->send_http_header();
$r->print("foo\n");
$r->print("bar\n");
}';
}
This also seems to be the only way to correctly handle filter finalization
in various complex cases, for example, when embedded perl is used both
in the original handler and in an error page called after filter
finalization.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Fri, 12 Jul 2019 11:29:22 +0300 |
parents | 3908156a51fa |
children | 359b0ea2b067 |
line wrap: on
line source
/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_stream.h> typedef struct { u_char color; u_char len; u_short conn; u_char data[1]; } ngx_stream_limit_conn_node_t; typedef struct { ngx_shm_zone_t *shm_zone; ngx_rbtree_node_t *node; } ngx_stream_limit_conn_cleanup_t; typedef struct { ngx_rbtree_t *rbtree; ngx_stream_complex_value_t key; } ngx_stream_limit_conn_ctx_t; typedef struct { ngx_shm_zone_t *shm_zone; ngx_uint_t conn; } ngx_stream_limit_conn_limit_t; typedef struct { ngx_array_t limits; ngx_uint_t log_level; } ngx_stream_limit_conn_conf_t; static ngx_rbtree_node_t *ngx_stream_limit_conn_lookup(ngx_rbtree_t *rbtree, ngx_str_t *key, uint32_t hash); static void ngx_stream_limit_conn_cleanup(void *data); static ngx_inline void ngx_stream_limit_conn_cleanup_all(ngx_pool_t *pool); static void *ngx_stream_limit_conn_create_conf(ngx_conf_t *cf); static char *ngx_stream_limit_conn_merge_conf(ngx_conf_t *cf, void *parent, void *child); static char *ngx_stream_limit_conn_zone(ngx_conf_t *cf, ngx_command_t *cmd, void *conf); static char *ngx_stream_limit_conn(ngx_conf_t *cf, ngx_command_t *cmd, void *conf); static ngx_int_t ngx_stream_limit_conn_init(ngx_conf_t *cf); static ngx_conf_enum_t ngx_stream_limit_conn_log_levels[] = { { ngx_string("info"), NGX_LOG_INFO }, { ngx_string("notice"), NGX_LOG_NOTICE }, { ngx_string("warn"), NGX_LOG_WARN }, { ngx_string("error"), NGX_LOG_ERR }, { ngx_null_string, 0 } }; static ngx_command_t ngx_stream_limit_conn_commands[] = { { ngx_string("limit_conn_zone"), NGX_STREAM_MAIN_CONF|NGX_CONF_TAKE2, ngx_stream_limit_conn_zone, 0, 0, NULL }, { ngx_string("limit_conn"), NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_TAKE2, ngx_stream_limit_conn, NGX_STREAM_SRV_CONF_OFFSET, 0, NULL }, { ngx_string("limit_conn_log_level"), NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_TAKE1, ngx_conf_set_enum_slot, NGX_STREAM_SRV_CONF_OFFSET, offsetof(ngx_stream_limit_conn_conf_t, log_level), &ngx_stream_limit_conn_log_levels }, ngx_null_command }; static ngx_stream_module_t ngx_stream_limit_conn_module_ctx = { NULL, /* preconfiguration */ ngx_stream_limit_conn_init, /* postconfiguration */ NULL, /* create main configuration */ NULL, /* init main configuration */ ngx_stream_limit_conn_create_conf, /* create server configuration */ ngx_stream_limit_conn_merge_conf /* merge server configuration */ }; ngx_module_t ngx_stream_limit_conn_module = { NGX_MODULE_V1, &ngx_stream_limit_conn_module_ctx, /* module context */ ngx_stream_limit_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_limit_conn_handler(ngx_stream_session_t *s) { size_t n; uint32_t hash; ngx_str_t key; ngx_uint_t i; ngx_slab_pool_t *shpool; ngx_rbtree_node_t *node; ngx_pool_cleanup_t *cln; ngx_stream_limit_conn_ctx_t *ctx; ngx_stream_limit_conn_node_t *lc; ngx_stream_limit_conn_conf_t *lccf; ngx_stream_limit_conn_limit_t *limits; ngx_stream_limit_conn_cleanup_t *lccln; lccf = ngx_stream_get_module_srv_conf(s, ngx_stream_limit_conn_module); limits = lccf->limits.elts; for (i = 0; i < lccf->limits.nelts; i++) { ctx = limits[i].shm_zone->data; if (ngx_stream_complex_value(s, &ctx->key, &key) != NGX_OK) { return NGX_ERROR; } if (key.len == 0) { continue; } if (key.len > 255) { ngx_log_error(NGX_LOG_ERR, s->connection->log, 0, "the value of the \"%V\" key " "is more than 255 bytes: \"%V\"", &ctx->key.value, &key); continue; } hash = ngx_crc32_short(key.data, key.len); shpool = (ngx_slab_pool_t *) limits[i].shm_zone->shm.addr; ngx_shmtx_lock(&shpool->mutex); node = ngx_stream_limit_conn_lookup(ctx->rbtree, &key, hash); if (node == NULL) { n = offsetof(ngx_rbtree_node_t, color) + offsetof(ngx_stream_limit_conn_node_t, data) + key.len; node = ngx_slab_alloc_locked(shpool, n); if (node == NULL) { ngx_shmtx_unlock(&shpool->mutex); ngx_stream_limit_conn_cleanup_all(s->connection->pool); return NGX_STREAM_SERVICE_UNAVAILABLE; } lc = (ngx_stream_limit_conn_node_t *) &node->color; node->key = hash; lc->len = (u_char) key.len; lc->conn = 1; ngx_memcpy(lc->data, key.data, key.len); ngx_rbtree_insert(ctx->rbtree, node); } else { lc = (ngx_stream_limit_conn_node_t *) &node->color; if ((ngx_uint_t) lc->conn >= limits[i].conn) { ngx_shmtx_unlock(&shpool->mutex); ngx_log_error(lccf->log_level, s->connection->log, 0, "limiting connections by zone \"%V\"", &limits[i].shm_zone->shm.name); ngx_stream_limit_conn_cleanup_all(s->connection->pool); return NGX_STREAM_SERVICE_UNAVAILABLE; } lc->conn++; } ngx_log_debug2(NGX_LOG_DEBUG_STREAM, s->connection->log, 0, "limit conn: %08Xi %d", node->key, lc->conn); ngx_shmtx_unlock(&shpool->mutex); cln = ngx_pool_cleanup_add(s->connection->pool, sizeof(ngx_stream_limit_conn_cleanup_t)); if (cln == NULL) { return NGX_ERROR; } cln->handler = ngx_stream_limit_conn_cleanup; lccln = cln->data; lccln->shm_zone = limits[i].shm_zone; lccln->node = node; } return NGX_DECLINED; } static void ngx_stream_limit_conn_rbtree_insert_value(ngx_rbtree_node_t *temp, ngx_rbtree_node_t *node, ngx_rbtree_node_t *sentinel) { ngx_rbtree_node_t **p; ngx_stream_limit_conn_node_t *lcn, *lcnt; for ( ;; ) { if (node->key < temp->key) { p = &temp->left; } else if (node->key > temp->key) { p = &temp->right; } else { /* node->key == temp->key */ lcn = (ngx_stream_limit_conn_node_t *) &node->color; lcnt = (ngx_stream_limit_conn_node_t *) &temp->color; p = (ngx_memn2cmp(lcn->data, lcnt->data, lcn->len, lcnt->len) < 0) ? &temp->left : &temp->right; } if (*p == sentinel) { break; } temp = *p; } *p = node; node->parent = temp; node->left = sentinel; node->right = sentinel; ngx_rbt_red(node); } static ngx_rbtree_node_t * ngx_stream_limit_conn_lookup(ngx_rbtree_t *rbtree, ngx_str_t *key, uint32_t hash) { ngx_int_t rc; ngx_rbtree_node_t *node, *sentinel; ngx_stream_limit_conn_node_t *lcn; node = rbtree->root; sentinel = rbtree->sentinel; while (node != sentinel) { if (hash < node->key) { node = node->left; continue; } if (hash > node->key) { node = node->right; continue; } /* hash == node->key */ lcn = (ngx_stream_limit_conn_node_t *) &node->color; rc = ngx_memn2cmp(key->data, lcn->data, key->len, (size_t) lcn->len); if (rc == 0) { return node; } node = (rc < 0) ? node->left : node->right; } return NULL; } static void ngx_stream_limit_conn_cleanup(void *data) { ngx_stream_limit_conn_cleanup_t *lccln = data; ngx_slab_pool_t *shpool; ngx_rbtree_node_t *node; ngx_stream_limit_conn_ctx_t *ctx; ngx_stream_limit_conn_node_t *lc; ctx = lccln->shm_zone->data; shpool = (ngx_slab_pool_t *) lccln->shm_zone->shm.addr; node = lccln->node; lc = (ngx_stream_limit_conn_node_t *) &node->color; ngx_shmtx_lock(&shpool->mutex); ngx_log_debug2(NGX_LOG_DEBUG_STREAM, lccln->shm_zone->shm.log, 0, "limit conn cleanup: %08Xi %d", node->key, lc->conn); lc->conn--; if (lc->conn == 0) { ngx_rbtree_delete(ctx->rbtree, node); ngx_slab_free_locked(shpool, node); } ngx_shmtx_unlock(&shpool->mutex); } static ngx_inline void ngx_stream_limit_conn_cleanup_all(ngx_pool_t *pool) { ngx_pool_cleanup_t *cln; cln = pool->cleanup; while (cln && cln->handler == ngx_stream_limit_conn_cleanup) { ngx_stream_limit_conn_cleanup(cln->data); cln = cln->next; } pool->cleanup = cln; } static ngx_int_t ngx_stream_limit_conn_init_zone(ngx_shm_zone_t *shm_zone, void *data) { ngx_stream_limit_conn_ctx_t *octx = data; size_t len; ngx_slab_pool_t *shpool; ngx_rbtree_node_t *sentinel; ngx_stream_limit_conn_ctx_t *ctx; ctx = shm_zone->data; if (octx) { if (ctx->key.value.len != octx->key.value.len || ngx_strncmp(ctx->key.value.data, octx->key.value.data, ctx->key.value.len) != 0) { ngx_log_error(NGX_LOG_EMERG, shm_zone->shm.log, 0, "limit_conn_zone \"%V\" uses the \"%V\" key " "while previously it used the \"%V\" key", &shm_zone->shm.name, &ctx->key.value, &octx->key.value); return NGX_ERROR; } ctx->rbtree = octx->rbtree; return NGX_OK; } shpool = (ngx_slab_pool_t *) shm_zone->shm.addr; if (shm_zone->shm.exists) { ctx->rbtree = shpool->data; return NGX_OK; } ctx->rbtree = ngx_slab_alloc(shpool, sizeof(ngx_rbtree_t)); if (ctx->rbtree == NULL) { return NGX_ERROR; } shpool->data = ctx->rbtree; sentinel = ngx_slab_alloc(shpool, sizeof(ngx_rbtree_node_t)); if (sentinel == NULL) { return NGX_ERROR; } ngx_rbtree_init(ctx->rbtree, sentinel, ngx_stream_limit_conn_rbtree_insert_value); len = sizeof(" in limit_conn_zone \"\"") + shm_zone->shm.name.len; shpool->log_ctx = ngx_slab_alloc(shpool, len); if (shpool->log_ctx == NULL) { return NGX_ERROR; } ngx_sprintf(shpool->log_ctx, " in limit_conn_zone \"%V\"%Z", &shm_zone->shm.name); return NGX_OK; } static void * ngx_stream_limit_conn_create_conf(ngx_conf_t *cf) { ngx_stream_limit_conn_conf_t *conf; conf = ngx_pcalloc(cf->pool, sizeof(ngx_stream_limit_conn_conf_t)); if (conf == NULL) { return NULL; } /* * set by ngx_pcalloc(): * * conf->limits.elts = NULL; */ conf->log_level = NGX_CONF_UNSET_UINT; return conf; } static char * ngx_stream_limit_conn_merge_conf(ngx_conf_t *cf, void *parent, void *child) { ngx_stream_limit_conn_conf_t *prev = parent; ngx_stream_limit_conn_conf_t *conf = child; if (conf->limits.elts == NULL) { conf->limits = prev->limits; } ngx_conf_merge_uint_value(conf->log_level, prev->log_level, NGX_LOG_ERR); return NGX_CONF_OK; } static char * ngx_stream_limit_conn_zone(ngx_conf_t *cf, ngx_command_t *cmd, void *conf) { u_char *p; ssize_t size; ngx_str_t *value, name, s; ngx_uint_t i; ngx_shm_zone_t *shm_zone; ngx_stream_limit_conn_ctx_t *ctx; ngx_stream_compile_complex_value_t ccv; value = cf->args->elts; ctx = ngx_pcalloc(cf->pool, sizeof(ngx_stream_limit_conn_ctx_t)); if (ctx == NULL) { return NGX_CONF_ERROR; } ngx_memzero(&ccv, sizeof(ngx_stream_compile_complex_value_t)); ccv.cf = cf; ccv.value = &value[1]; ccv.complex_value = &ctx->key; if (ngx_stream_compile_complex_value(&ccv) != NGX_OK) { return NGX_CONF_ERROR; } size = 0; name.len = 0; for (i = 2; i < cf->args->nelts; i++) { if (ngx_strncmp(value[i].data, "zone=", 5) == 0) { name.data = value[i].data + 5; p = (u_char *) ngx_strchr(name.data, ':'); if (p == NULL) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "invalid zone size \"%V\"", &value[i]); return NGX_CONF_ERROR; } name.len = p - name.data; s.data = p + 1; s.len = value[i].data + value[i].len - s.data; size = ngx_parse_size(&s); if (size == NGX_ERROR) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "invalid zone size \"%V\"", &value[i]); return NGX_CONF_ERROR; } if (size < (ssize_t) (8 * ngx_pagesize)) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "zone \"%V\" is too small", &value[i]); return NGX_CONF_ERROR; } continue; } ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "invalid parameter \"%V\"", &value[i]); return NGX_CONF_ERROR; } if (name.len == 0) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "\"%V\" must have \"zone\" parameter", &cmd->name); return NGX_CONF_ERROR; } shm_zone = ngx_shared_memory_add(cf, &name, size, &ngx_stream_limit_conn_module); if (shm_zone == NULL) { return NGX_CONF_ERROR; } if (shm_zone->data) { ctx = shm_zone->data; ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "%V \"%V\" is already bound to key \"%V\"", &cmd->name, &name, &ctx->key.value); return NGX_CONF_ERROR; } shm_zone->init = ngx_stream_limit_conn_init_zone; shm_zone->data = ctx; return NGX_CONF_OK; } static char * ngx_stream_limit_conn(ngx_conf_t *cf, ngx_command_t *cmd, void *conf) { ngx_shm_zone_t *shm_zone; ngx_stream_limit_conn_conf_t *lccf = conf; ngx_stream_limit_conn_limit_t *limit, *limits; ngx_str_t *value; ngx_int_t n; ngx_uint_t i; value = cf->args->elts; shm_zone = ngx_shared_memory_add(cf, &value[1], 0, &ngx_stream_limit_conn_module); if (shm_zone == NULL) { return NGX_CONF_ERROR; } limits = lccf->limits.elts; if (limits == NULL) { if (ngx_array_init(&lccf->limits, cf->pool, 1, sizeof(ngx_stream_limit_conn_limit_t)) != NGX_OK) { return NGX_CONF_ERROR; } } for (i = 0; i < lccf->limits.nelts; i++) { if (shm_zone == limits[i].shm_zone) { return "is duplicate"; } } n = ngx_atoi(value[2].data, value[2].len); if (n <= 0) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "invalid number of connections \"%V\"", &value[2]); return NGX_CONF_ERROR; } if (n > 65535) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "connection limit must be less 65536"); return NGX_CONF_ERROR; } limit = ngx_array_push(&lccf->limits); if (limit == NULL) { return NGX_CONF_ERROR; } limit->conn = n; limit->shm_zone = shm_zone; return NGX_CONF_OK; } static ngx_int_t ngx_stream_limit_conn_init(ngx_conf_t *cf) { ngx_stream_handler_pt *h; ngx_stream_core_main_conf_t *cmcf; cmcf = ngx_stream_conf_get_module_main_conf(cf, ngx_stream_core_module); h = ngx_array_push(&cmcf->phases[NGX_STREAM_PREACCESS_PHASE].handlers); if (h == NULL) { return NGX_ERROR; } *h = ngx_stream_limit_conn_handler; return NGX_OK; }