Mercurial > hg > nginx
view src/http/modules/ngx_http_realip_module.c @ 9300:5be23505292b default tip
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 | ef6a3a99a81a |
children |
line wrap: on
line source
/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_http.h> #define NGX_HTTP_REALIP_XREALIP 0 #define NGX_HTTP_REALIP_XFWD 1 #define NGX_HTTP_REALIP_HEADER 2 #define NGX_HTTP_REALIP_PROXY 3 typedef struct { ngx_array_t *from; /* array of ngx_cidr_t */ ngx_uint_t type; ngx_uint_t hash; ngx_str_t header; ngx_flag_t recursive; } ngx_http_realip_loc_conf_t; typedef struct { ngx_connection_t *connection; struct sockaddr *sockaddr; socklen_t socklen; ngx_str_t addr_text; } ngx_http_realip_ctx_t; static ngx_int_t ngx_http_realip_handler(ngx_http_request_t *r); static ngx_int_t ngx_http_realip_set_addr(ngx_http_request_t *r, ngx_addr_t *addr); static void ngx_http_realip_cleanup(void *data); static char *ngx_http_realip_from(ngx_conf_t *cf, ngx_command_t *cmd, void *conf); static char *ngx_http_realip(ngx_conf_t *cf, ngx_command_t *cmd, void *conf); static void *ngx_http_realip_create_loc_conf(ngx_conf_t *cf); static char *ngx_http_realip_merge_loc_conf(ngx_conf_t *cf, void *parent, void *child); static ngx_int_t ngx_http_realip_add_variables(ngx_conf_t *cf); static ngx_int_t ngx_http_realip_init(ngx_conf_t *cf); static ngx_http_realip_ctx_t *ngx_http_realip_get_module_ctx( ngx_http_request_t *r); static ngx_int_t ngx_http_realip_remote_addr_variable(ngx_http_request_t *r, ngx_http_variable_value_t *v, uintptr_t data); static ngx_int_t ngx_http_realip_remote_port_variable(ngx_http_request_t *r, ngx_http_variable_value_t *v, uintptr_t data); static ngx_command_t ngx_http_realip_commands[] = { { ngx_string("set_real_ip_from"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1, ngx_http_realip_from, NGX_HTTP_LOC_CONF_OFFSET, 0, NULL }, { ngx_string("real_ip_header"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1, ngx_http_realip, NGX_HTTP_LOC_CONF_OFFSET, 0, NULL }, { ngx_string("real_ip_recursive"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_FLAG, ngx_conf_set_flag_slot, NGX_HTTP_LOC_CONF_OFFSET, offsetof(ngx_http_realip_loc_conf_t, recursive), NULL }, ngx_null_command }; static ngx_http_module_t ngx_http_realip_module_ctx = { ngx_http_realip_add_variables, /* preconfiguration */ ngx_http_realip_init, /* postconfiguration */ NULL, /* create main configuration */ NULL, /* init main configuration */ NULL, /* create server configuration */ NULL, /* merge server configuration */ ngx_http_realip_create_loc_conf, /* create location configuration */ ngx_http_realip_merge_loc_conf /* merge location configuration */ }; ngx_module_t ngx_http_realip_module = { NGX_MODULE_V1, &ngx_http_realip_module_ctx, /* module context */ ngx_http_realip_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_http_variable_t ngx_http_realip_vars[] = { { ngx_string("realip_remote_addr"), NULL, ngx_http_realip_remote_addr_variable, 0, 0, 0 }, { ngx_string("realip_remote_port"), NULL, ngx_http_realip_remote_port_variable, 0, 0, 0 }, ngx_http_null_variable }; static ngx_int_t ngx_http_realip_handler(ngx_http_request_t *r) { u_char *p; size_t len; ngx_str_t *value; ngx_uint_t i, hash; ngx_addr_t addr; ngx_list_part_t *part; ngx_table_elt_t *header, *xfwd; ngx_connection_t *c; ngx_http_realip_ctx_t *ctx; ngx_http_realip_loc_conf_t *rlcf; rlcf = ngx_http_get_module_loc_conf(r, ngx_http_realip_module); if (rlcf->from == NULL) { return NGX_DECLINED; } ctx = ngx_http_realip_get_module_ctx(r); if (ctx) { return NGX_DECLINED; } switch (rlcf->type) { case NGX_HTTP_REALIP_XREALIP: if (r->headers_in.x_real_ip == NULL) { return NGX_DECLINED; } value = &r->headers_in.x_real_ip->value; xfwd = NULL; break; case NGX_HTTP_REALIP_XFWD: xfwd = r->headers_in.x_forwarded_for; if (xfwd == NULL) { return NGX_DECLINED; } value = NULL; break; case NGX_HTTP_REALIP_PROXY: if (r->connection->proxy_protocol == NULL) { return NGX_DECLINED; } value = &r->connection->proxy_protocol->src_addr; xfwd = NULL; break; default: /* NGX_HTTP_REALIP_HEADER */ part = &r->headers_in.headers.part; header = part->elts; hash = rlcf->hash; len = rlcf->header.len; p = rlcf->header.data; for (i = 0; /* void */ ; i++) { if (i >= part->nelts) { if (part->next == NULL) { break; } part = part->next; header = part->elts; i = 0; } if (hash == header[i].hash && len == header[i].key.len && ngx_strncmp(p, header[i].lowcase_key, len) == 0) { value = &header[i].value; xfwd = NULL; goto found; } } return NGX_DECLINED; } found: c = r->connection; addr.sockaddr = c->sockaddr; addr.socklen = c->socklen; /* addr.name = c->addr_text; */ if (ngx_http_get_forwarded_addr(r, &addr, xfwd, value, rlcf->from, rlcf->recursive) != NGX_DECLINED) { if (rlcf->type == NGX_HTTP_REALIP_PROXY) { ngx_inet_set_port(addr.sockaddr, c->proxy_protocol->src_port); } return ngx_http_realip_set_addr(r, &addr); } return NGX_DECLINED; } static ngx_int_t ngx_http_realip_set_addr(ngx_http_request_t *r, ngx_addr_t *addr) { size_t len; u_char *p; u_char text[NGX_SOCKADDR_STRLEN]; ngx_connection_t *c; ngx_pool_cleanup_t *cln; ngx_http_realip_ctx_t *ctx; cln = ngx_pool_cleanup_add(r->pool, sizeof(ngx_http_realip_ctx_t)); if (cln == NULL) { return NGX_HTTP_INTERNAL_SERVER_ERROR; } ctx = cln->data; c = r->connection; len = ngx_sock_ntop(addr->sockaddr, addr->socklen, text, NGX_SOCKADDR_STRLEN, 0); if (len == 0) { return NGX_HTTP_INTERNAL_SERVER_ERROR; } p = ngx_pnalloc(c->pool, len); if (p == NULL) { return NGX_HTTP_INTERNAL_SERVER_ERROR; } ngx_memcpy(p, text, len); cln->handler = ngx_http_realip_cleanup; ngx_http_set_ctx(r, ctx, ngx_http_realip_module); ctx->connection = c; ctx->sockaddr = c->sockaddr; ctx->socklen = c->socklen; ctx->addr_text = c->addr_text; c->sockaddr = addr->sockaddr; c->socklen = addr->socklen; c->addr_text.len = len; c->addr_text.data = p; return NGX_DECLINED; } static void ngx_http_realip_cleanup(void *data) { ngx_http_realip_ctx_t *ctx = data; ngx_connection_t *c; c = ctx->connection; c->sockaddr = ctx->sockaddr; c->socklen = ctx->socklen; c->addr_text = ctx->addr_text; } static char * ngx_http_realip_from(ngx_conf_t *cf, ngx_command_t *cmd, void *conf) { ngx_http_realip_loc_conf_t *rlcf = conf; ngx_int_t rc; ngx_str_t *value; ngx_url_t u; ngx_cidr_t c, *cidr; ngx_uint_t i; struct sockaddr_in *sin; #if (NGX_HAVE_INET6) struct sockaddr_in6 *sin6; #endif value = cf->args->elts; if (rlcf->from == NULL) { rlcf->from = ngx_array_create(cf->pool, 2, sizeof(ngx_cidr_t)); if (rlcf->from == NULL) { return NGX_CONF_ERROR; } } #if (NGX_HAVE_UNIX_DOMAIN) if (ngx_strcmp(value[1].data, "unix:") == 0) { cidr = ngx_array_push(rlcf->from); if (cidr == NULL) { return NGX_CONF_ERROR; } cidr->family = AF_UNIX; return NGX_CONF_OK; } #endif rc = ngx_ptocidr(&value[1], &c); if (rc != NGX_ERROR) { if (rc == NGX_DONE) { ngx_conf_log_error(NGX_LOG_WARN, cf, 0, "low address bits of %V are meaningless", &value[1]); } cidr = ngx_array_push(rlcf->from); if (cidr == NULL) { return NGX_CONF_ERROR; } *cidr = c; return NGX_CONF_OK; } ngx_memzero(&u, sizeof(ngx_url_t)); u.host = value[1]; if (ngx_inet_resolve_host(cf->pool, &u) != NGX_OK) { if (u.err) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "%s in set_real_ip_from \"%V\"", u.err, &u.host); } return NGX_CONF_ERROR; } cidr = ngx_array_push_n(rlcf->from, u.naddrs); if (cidr == NULL) { return NGX_CONF_ERROR; } ngx_memzero(cidr, u.naddrs * sizeof(ngx_cidr_t)); for (i = 0; i < u.naddrs; i++) { cidr[i].family = u.addrs[i].sockaddr->sa_family; switch (cidr[i].family) { #if (NGX_HAVE_INET6) case AF_INET6: sin6 = (struct sockaddr_in6 *) u.addrs[i].sockaddr; cidr[i].u.in6.addr = sin6->sin6_addr; ngx_memset(cidr[i].u.in6.mask.s6_addr, 0xff, 16); break; #endif default: /* AF_INET */ sin = (struct sockaddr_in *) u.addrs[i].sockaddr; cidr[i].u.in.addr = sin->sin_addr.s_addr; cidr[i].u.in.mask = 0xffffffff; break; } } return NGX_CONF_OK; } static char * ngx_http_realip(ngx_conf_t *cf, ngx_command_t *cmd, void *conf) { ngx_http_realip_loc_conf_t *rlcf = conf; ngx_str_t *value; if (rlcf->type != NGX_CONF_UNSET_UINT) { return "is duplicate"; } value = cf->args->elts; if (ngx_strcmp(value[1].data, "X-Real-IP") == 0) { rlcf->type = NGX_HTTP_REALIP_XREALIP; return NGX_CONF_OK; } if (ngx_strcmp(value[1].data, "X-Forwarded-For") == 0) { rlcf->type = NGX_HTTP_REALIP_XFWD; return NGX_CONF_OK; } if (ngx_strcmp(value[1].data, "proxy_protocol") == 0) { rlcf->type = NGX_HTTP_REALIP_PROXY; return NGX_CONF_OK; } rlcf->type = NGX_HTTP_REALIP_HEADER; rlcf->hash = ngx_hash_strlow(value[1].data, value[1].data, value[1].len); rlcf->header = value[1]; return NGX_CONF_OK; } static void * ngx_http_realip_create_loc_conf(ngx_conf_t *cf) { ngx_http_realip_loc_conf_t *conf; conf = ngx_pcalloc(cf->pool, sizeof(ngx_http_realip_loc_conf_t)); if (conf == NULL) { return NULL; } /* * set by ngx_pcalloc(): * * conf->from = NULL; * conf->hash = 0; * conf->header = { 0, NULL }; */ conf->type = NGX_CONF_UNSET_UINT; conf->recursive = NGX_CONF_UNSET; return conf; } static char * ngx_http_realip_merge_loc_conf(ngx_conf_t *cf, void *parent, void *child) { ngx_http_realip_loc_conf_t *prev = parent; ngx_http_realip_loc_conf_t *conf = child; if (conf->from == NULL) { conf->from = prev->from; } ngx_conf_merge_uint_value(conf->type, prev->type, NGX_HTTP_REALIP_XREALIP); ngx_conf_merge_value(conf->recursive, prev->recursive, 0); if (conf->header.len == 0) { conf->hash = prev->hash; conf->header = prev->header; } return NGX_CONF_OK; } static ngx_int_t ngx_http_realip_add_variables(ngx_conf_t *cf) { ngx_http_variable_t *var, *v; for (v = ngx_http_realip_vars; v->name.len; v++) { var = ngx_http_add_variable(cf, &v->name, v->flags); if (var == NULL) { return NGX_ERROR; } var->get_handler = v->get_handler; var->data = v->data; } return NGX_OK; } static ngx_int_t ngx_http_realip_init(ngx_conf_t *cf) { ngx_http_handler_pt *h; ngx_http_core_main_conf_t *cmcf; cmcf = ngx_http_conf_get_module_main_conf(cf, ngx_http_core_module); h = ngx_array_push(&cmcf->phases[NGX_HTTP_POST_READ_PHASE].handlers); if (h == NULL) { return NGX_ERROR; } *h = ngx_http_realip_handler; h = ngx_array_push(&cmcf->phases[NGX_HTTP_PREACCESS_PHASE].handlers); if (h == NULL) { return NGX_ERROR; } *h = ngx_http_realip_handler; return NGX_OK; } static ngx_http_realip_ctx_t * ngx_http_realip_get_module_ctx(ngx_http_request_t *r) { ngx_pool_cleanup_t *cln; ngx_http_realip_ctx_t *ctx; ctx = ngx_http_get_module_ctx(r, ngx_http_realip_module); if (ctx == NULL && (r->internal || r->filter_finalize)) { /* * if module context was reset, the original address * can still be found in the cleanup handler */ for (cln = r->pool->cleanup; cln; cln = cln->next) { if (cln->handler == ngx_http_realip_cleanup) { ctx = cln->data; break; } } } return ctx; } static ngx_int_t ngx_http_realip_remote_addr_variable(ngx_http_request_t *r, ngx_http_variable_value_t *v, uintptr_t data) { ngx_str_t *addr_text; ngx_http_realip_ctx_t *ctx; ctx = ngx_http_realip_get_module_ctx(r); addr_text = ctx ? &ctx->addr_text : &r->connection->addr_text; v->len = addr_text->len; v->valid = 1; v->no_cacheable = 0; v->not_found = 0; v->data = addr_text->data; return NGX_OK; } static ngx_int_t ngx_http_realip_remote_port_variable(ngx_http_request_t *r, ngx_http_variable_value_t *v, uintptr_t data) { ngx_uint_t port; struct sockaddr *sa; ngx_http_realip_ctx_t *ctx; ctx = ngx_http_realip_get_module_ctx(r); sa = ctx ? ctx->sockaddr : r->connection->sockaddr; v->len = 0; v->valid = 1; v->no_cacheable = 0; v->not_found = 0; v->data = ngx_pnalloc(r->pool, sizeof("65535") - 1); if (v->data == NULL) { return NGX_ERROR; } port = ngx_inet_get_port(sa); if (port > 0 && port < 65536) { v->len = ngx_sprintf(v->data, "%ui", port) - v->data; } return NGX_OK; }