Mercurial > hg > nginx
view src/http/modules/ngx_http_map_module.c @ 9300:5be23505292b
SSI: fixed incorrect or duplicate stub output.
Following 3518:eb3aaf8bd2a9 (0.8.37), r->request_output is only set
if there are data in the first buffer sent in the subrequest. As a
result, following the change mentioned this flag cannot be used to
prevent duplicate ngx_http_ssi_stub_output() calls, since it is not
set if there was already some output, but the first buffer was empty.
Still, when there are multiple subrequests, even an empty subrequest
response might be delayed by the postpone filter, leading to a second
call of ngx_http_ssi_stub_output() during finalization from
ngx_http_writer() the subreqest buffers are released by the postpone
filter. Since r->request_output is not set after the first call, this
resulted in duplicate stub output.
Additionally, checking only the first buffer might be wrong in some
unusual cases. For example, the first buffer might be empty if
$r->flush() is called before printing any data in the embedded Perl
module.
Depending on the postpone_output value and corresponding sizes, this
issue can result in either duplicate or unexpected stub output, or
"zero size buf in writer" alerts.
Following 8124:f5515e727656 (1.23.4), it became slightly easier to
reproduce the issue, as empty static files and empty cache items now
result in a response with an empty buffer. Before the change, an empty
proxied response can be used to reproduce the issue.
Fix is check all buffers and set r->request_output if any non-empty
buffers are sent. This ensures that all unusual cases of non-empty
responses are covered, and also that r->request_output will be set
after the first stub output, preventing duplicate output.
Reported by Jan Gassen.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Thu, 04 Jul 2024 17:41:28 +0300 |
parents | ec10ce307dc0 |
children |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_http.h> typedef struct { ngx_uint_t hash_max_size; ngx_uint_t hash_bucket_size; } ngx_http_map_conf_t; typedef struct { ngx_hash_keys_arrays_t keys; ngx_array_t *values_hash; #if (NGX_PCRE) ngx_array_t regexes; #endif ngx_http_variable_value_t *default_value; ngx_conf_t *cf; unsigned hostnames:1; unsigned no_cacheable:1; } ngx_http_map_conf_ctx_t; typedef struct { ngx_http_map_t map; ngx_http_complex_value_t value; ngx_http_variable_value_t *default_value; ngx_uint_t hostnames; /* unsigned hostnames:1 */ } ngx_http_map_ctx_t; static int ngx_libc_cdecl ngx_http_map_cmp_dns_wildcards(const void *one, const void *two); static void *ngx_http_map_create_conf(ngx_conf_t *cf); static char *ngx_http_map_block(ngx_conf_t *cf, ngx_command_t *cmd, void *conf); static char *ngx_http_map(ngx_conf_t *cf, ngx_command_t *dummy, void *conf); static ngx_command_t ngx_http_map_commands[] = { { ngx_string("map"), NGX_HTTP_MAIN_CONF|NGX_CONF_BLOCK|NGX_CONF_TAKE2, ngx_http_map_block, NGX_HTTP_MAIN_CONF_OFFSET, 0, NULL }, { ngx_string("map_hash_max_size"), NGX_HTTP_MAIN_CONF|NGX_CONF_TAKE1, ngx_conf_set_num_slot, NGX_HTTP_MAIN_CONF_OFFSET, offsetof(ngx_http_map_conf_t, hash_max_size), NULL }, { ngx_string("map_hash_bucket_size"), NGX_HTTP_MAIN_CONF|NGX_CONF_TAKE1, ngx_conf_set_num_slot, NGX_HTTP_MAIN_CONF_OFFSET, offsetof(ngx_http_map_conf_t, hash_bucket_size), NULL }, ngx_null_command }; static ngx_http_module_t ngx_http_map_module_ctx = { NULL, /* preconfiguration */ NULL, /* postconfiguration */ ngx_http_map_create_conf, /* 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_map_module = { NGX_MODULE_V1, &ngx_http_map_module_ctx, /* module context */ ngx_http_map_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_map_variable(ngx_http_request_t *r, ngx_http_variable_value_t *v, uintptr_t data) { ngx_http_map_ctx_t *map = (ngx_http_map_ctx_t *) data; ngx_str_t val, str; ngx_http_complex_value_t *cv; ngx_http_variable_value_t *value; ngx_log_debug0(NGX_LOG_DEBUG_HTTP, r->connection->log, 0, "http map started"); if (ngx_http_complex_value(r, &map->value, &val) != NGX_OK) { return NGX_ERROR; } if (map->hostnames && val.len > 0 && val.data[val.len - 1] == '.') { val.len--; } value = ngx_http_map_find(r, &map->map, &val); if (value == NULL) { value = map->default_value; } if (!value->valid) { cv = (ngx_http_complex_value_t *) value->data; if (ngx_http_complex_value(r, cv, &str) != NGX_OK) { return NGX_ERROR; } v->valid = 1; v->no_cacheable = 0; v->not_found = 0; v->len = str.len; v->data = str.data; } else { *v = *value; } ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0, "http map: \"%V\" \"%v\"", &val, v); return NGX_OK; } static void * ngx_http_map_create_conf(ngx_conf_t *cf) { ngx_http_map_conf_t *mcf; mcf = ngx_palloc(cf->pool, sizeof(ngx_http_map_conf_t)); if (mcf == NULL) { return NULL; } mcf->hash_max_size = NGX_CONF_UNSET_UINT; mcf->hash_bucket_size = NGX_CONF_UNSET_UINT; return mcf; } static char * ngx_http_map_block(ngx_conf_t *cf, ngx_command_t *cmd, void *conf) { ngx_http_map_conf_t *mcf = conf; char *rv; ngx_str_t *value, name; ngx_conf_t save; ngx_pool_t *pool; ngx_hash_init_t hash; ngx_http_map_ctx_t *map; ngx_http_variable_t *var; ngx_http_map_conf_ctx_t ctx; ngx_http_compile_complex_value_t ccv; if (mcf->hash_max_size == NGX_CONF_UNSET_UINT) { mcf->hash_max_size = 2048; } if (mcf->hash_bucket_size == NGX_CONF_UNSET_UINT) { mcf->hash_bucket_size = ngx_cacheline_size; } else { mcf->hash_bucket_size = ngx_align(mcf->hash_bucket_size, ngx_cacheline_size); } map = ngx_pcalloc(cf->pool, sizeof(ngx_http_map_ctx_t)); if (map == NULL) { return NGX_CONF_ERROR; } value = cf->args->elts; ngx_memzero(&ccv, sizeof(ngx_http_compile_complex_value_t)); ccv.cf = cf; ccv.value = &value[1]; ccv.complex_value = &map->value; if (ngx_http_compile_complex_value(&ccv) != NGX_OK) { return NGX_CONF_ERROR; } name = value[2]; if (name.data[0] != '$') { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "invalid variable name \"%V\"", &name); return NGX_CONF_ERROR; } name.len--; name.data++; var = ngx_http_add_variable(cf, &name, NGX_HTTP_VAR_CHANGEABLE); if (var == NULL) { return NGX_CONF_ERROR; } var->get_handler = ngx_http_map_variable; var->data = (uintptr_t) map; pool = ngx_create_pool(NGX_DEFAULT_POOL_SIZE, cf->log); if (pool == NULL) { return NGX_CONF_ERROR; } ctx.keys.pool = cf->pool; ctx.keys.temp_pool = pool; if (ngx_hash_keys_array_init(&ctx.keys, NGX_HASH_LARGE) != NGX_OK) { ngx_destroy_pool(pool); return NGX_CONF_ERROR; } ctx.values_hash = ngx_pcalloc(pool, sizeof(ngx_array_t) * ctx.keys.hsize); if (ctx.values_hash == NULL) { ngx_destroy_pool(pool); return NGX_CONF_ERROR; } #if (NGX_PCRE) if (ngx_array_init(&ctx.regexes, cf->pool, 2, sizeof(ngx_http_map_regex_t)) != NGX_OK) { ngx_destroy_pool(pool); return NGX_CONF_ERROR; } #endif ctx.default_value = NULL; ctx.cf = &save; ctx.hostnames = 0; ctx.no_cacheable = 0; save = *cf; cf->pool = pool; cf->ctx = &ctx; cf->handler = ngx_http_map; cf->handler_conf = conf; rv = ngx_conf_parse(cf, NULL); *cf = save; if (rv != NGX_CONF_OK) { ngx_destroy_pool(pool); return rv; } if (ctx.no_cacheable) { var->flags |= NGX_HTTP_VAR_NOCACHEABLE; } map->default_value = ctx.default_value ? ctx.default_value: &ngx_http_variable_null_value; map->hostnames = ctx.hostnames; hash.key = ngx_hash_key_lc; hash.max_size = mcf->hash_max_size; hash.bucket_size = mcf->hash_bucket_size; hash.name = "map_hash"; hash.pool = cf->pool; if (ctx.keys.keys.nelts) { hash.hash = &map->map.hash.hash; hash.temp_pool = NULL; if (ngx_hash_init(&hash, ctx.keys.keys.elts, ctx.keys.keys.nelts) != NGX_OK) { ngx_destroy_pool(pool); return NGX_CONF_ERROR; } } if (ctx.keys.dns_wc_head.nelts) { ngx_qsort(ctx.keys.dns_wc_head.elts, (size_t) ctx.keys.dns_wc_head.nelts, sizeof(ngx_hash_key_t), ngx_http_map_cmp_dns_wildcards); hash.hash = NULL; hash.temp_pool = pool; if (ngx_hash_wildcard_init(&hash, ctx.keys.dns_wc_head.elts, ctx.keys.dns_wc_head.nelts) != NGX_OK) { ngx_destroy_pool(pool); return NGX_CONF_ERROR; } map->map.hash.wc_head = (ngx_hash_wildcard_t *) hash.hash; } if (ctx.keys.dns_wc_tail.nelts) { ngx_qsort(ctx.keys.dns_wc_tail.elts, (size_t) ctx.keys.dns_wc_tail.nelts, sizeof(ngx_hash_key_t), ngx_http_map_cmp_dns_wildcards); hash.hash = NULL; hash.temp_pool = pool; if (ngx_hash_wildcard_init(&hash, ctx.keys.dns_wc_tail.elts, ctx.keys.dns_wc_tail.nelts) != NGX_OK) { ngx_destroy_pool(pool); return NGX_CONF_ERROR; } map->map.hash.wc_tail = (ngx_hash_wildcard_t *) hash.hash; } #if (NGX_PCRE) if (ctx.regexes.nelts) { map->map.regex = ctx.regexes.elts; map->map.nregex = ctx.regexes.nelts; } #endif ngx_destroy_pool(pool); return rv; } static int ngx_libc_cdecl ngx_http_map_cmp_dns_wildcards(const void *one, const void *two) { ngx_hash_key_t *first, *second; first = (ngx_hash_key_t *) one; second = (ngx_hash_key_t *) two; return ngx_dns_strcmp(first->key.data, second->key.data); } static char * ngx_http_map(ngx_conf_t *cf, ngx_command_t *dummy, void *conf) { u_char *data; size_t len; ngx_int_t rv; ngx_str_t *value, v; ngx_uint_t i, key; ngx_http_map_conf_ctx_t *ctx; ngx_http_complex_value_t cv, *cvp; ngx_http_variable_value_t *var, **vp; ngx_http_compile_complex_value_t ccv; ctx = cf->ctx; value = cf->args->elts; if (cf->args->nelts == 1 && ngx_strcmp(value[0].data, "hostnames") == 0) { ctx->hostnames = 1; return NGX_CONF_OK; } if (cf->args->nelts == 1 && ngx_strcmp(value[0].data, "volatile") == 0) { ctx->no_cacheable = 1; return NGX_CONF_OK; } if (cf->args->nelts != 2) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "invalid number of the map parameters"); return NGX_CONF_ERROR; } if (ngx_strcmp(value[0].data, "include") == 0) { return ngx_conf_include(cf, dummy, conf); } key = 0; for (i = 0; i < value[1].len; i++) { key = ngx_hash(key, value[1].data[i]); } key %= ctx->keys.hsize; vp = ctx->values_hash[key].elts; if (vp) { for (i = 0; i < ctx->values_hash[key].nelts; i++) { if (vp[i]->valid) { data = vp[i]->data; len = vp[i]->len; } else { cvp = (ngx_http_complex_value_t *) vp[i]->data; data = cvp->value.data; len = cvp->value.len; } if (value[1].len != len) { continue; } if (ngx_strncmp(value[1].data, data, len) == 0) { var = vp[i]; goto found; } } } else { if (ngx_array_init(&ctx->values_hash[key], cf->pool, 4, sizeof(ngx_http_variable_value_t *)) != NGX_OK) { return NGX_CONF_ERROR; } } var = ngx_palloc(ctx->keys.pool, sizeof(ngx_http_variable_value_t)); if (var == NULL) { return NGX_CONF_ERROR; } v.len = value[1].len; v.data = ngx_pstrdup(ctx->keys.pool, &value[1]); if (v.data == NULL) { return NGX_CONF_ERROR; } ngx_memzero(&ccv, sizeof(ngx_http_compile_complex_value_t)); ccv.cf = ctx->cf; ccv.value = &v; ccv.complex_value = &cv; if (ngx_http_compile_complex_value(&ccv) != NGX_OK) { return NGX_CONF_ERROR; } if (cv.lengths != NULL) { cvp = ngx_palloc(ctx->keys.pool, sizeof(ngx_http_complex_value_t)); if (cvp == NULL) { return NGX_CONF_ERROR; } *cvp = cv; var->len = 0; var->data = (u_char *) cvp; var->valid = 0; } else { var->len = v.len; var->data = v.data; var->valid = 1; } var->no_cacheable = 0; var->not_found = 0; vp = ngx_array_push(&ctx->values_hash[key]); if (vp == NULL) { return NGX_CONF_ERROR; } *vp = var; found: if (ngx_strcmp(value[0].data, "default") == 0) { if (ctx->default_value) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "duplicate default map parameter"); return NGX_CONF_ERROR; } ctx->default_value = var; return NGX_CONF_OK; } #if (NGX_PCRE) if (value[0].len && value[0].data[0] == '~') { ngx_regex_compile_t rc; ngx_http_map_regex_t *regex; u_char errstr[NGX_MAX_CONF_ERRSTR]; regex = ngx_array_push(&ctx->regexes); if (regex == NULL) { return NGX_CONF_ERROR; } value[0].len--; value[0].data++; ngx_memzero(&rc, sizeof(ngx_regex_compile_t)); if (value[0].data[0] == '*') { value[0].len--; value[0].data++; rc.options = NGX_REGEX_CASELESS; } rc.pattern = value[0]; rc.err.len = NGX_MAX_CONF_ERRSTR; rc.err.data = errstr; regex->regex = ngx_http_regex_compile(ctx->cf, &rc); if (regex->regex == NULL) { return NGX_CONF_ERROR; } regex->value = var; return NGX_CONF_OK; } #endif if (value[0].len && value[0].data[0] == '\\') { value[0].len--; value[0].data++; } rv = ngx_hash_add_key(&ctx->keys, &value[0], var, (ctx->hostnames) ? NGX_HASH_WILDCARD_KEY : 0); if (rv == NGX_OK) { return NGX_CONF_OK; } if (rv == NGX_DECLINED) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "invalid hostname or wildcard \"%V\"", &value[0]); } if (rv == NGX_BUSY) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "conflicting parameter \"%V\"", &value[0]); } return NGX_CONF_ERROR; }