Mercurial > hg > nginx-quic
view src/http/modules/ngx_http_access_module.c @ 8531:41f4bd4c51f1
Disabled control characters and space in header names.
Control characters (0x00-0x1f, 0x7f), space, and colon were never allowed in
header names. The only somewhat valid use is header continuation which nginx
never supported and which is explicitly obsolete by RFC 7230.
Previously, such headers were considered invalid and were ignored by default
(as per ignore_invalid_headers directive). With this change, such headers
are unconditionally rejected.
It is expected to make nginx more resilient to various attacks, in particular,
with ignore_invalid_headers switched off (which is inherently unsecure, though
nevertheless sometimes used in the wild).
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Mon, 28 Jun 2021 18:01:18 +0300 |
parents | 72188d1bcab5 |
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 { in_addr_t mask; in_addr_t addr; ngx_uint_t deny; /* unsigned deny:1; */ } ngx_http_access_rule_t; #if (NGX_HAVE_INET6) typedef struct { struct in6_addr addr; struct in6_addr mask; ngx_uint_t deny; /* unsigned deny:1; */ } ngx_http_access_rule6_t; #endif #if (NGX_HAVE_UNIX_DOMAIN) typedef struct { ngx_uint_t deny; /* unsigned deny:1; */ } ngx_http_access_rule_un_t; #endif typedef struct { ngx_array_t *rules; /* array of ngx_http_access_rule_t */ #if (NGX_HAVE_INET6) ngx_array_t *rules6; /* array of ngx_http_access_rule6_t */ #endif #if (NGX_HAVE_UNIX_DOMAIN) ngx_array_t *rules_un; /* array of ngx_http_access_rule_un_t */ #endif } ngx_http_access_loc_conf_t; static ngx_int_t ngx_http_access_handler(ngx_http_request_t *r); static ngx_int_t ngx_http_access_inet(ngx_http_request_t *r, ngx_http_access_loc_conf_t *alcf, in_addr_t addr); #if (NGX_HAVE_INET6) static ngx_int_t ngx_http_access_inet6(ngx_http_request_t *r, ngx_http_access_loc_conf_t *alcf, u_char *p); #endif #if (NGX_HAVE_UNIX_DOMAIN) static ngx_int_t ngx_http_access_unix(ngx_http_request_t *r, ngx_http_access_loc_conf_t *alcf); #endif static ngx_int_t ngx_http_access_found(ngx_http_request_t *r, ngx_uint_t deny); static char *ngx_http_access_rule(ngx_conf_t *cf, ngx_command_t *cmd, void *conf); static void *ngx_http_access_create_loc_conf(ngx_conf_t *cf); static char *ngx_http_access_merge_loc_conf(ngx_conf_t *cf, void *parent, void *child); static ngx_int_t ngx_http_access_init(ngx_conf_t *cf); static ngx_command_t ngx_http_access_commands[] = { { ngx_string("allow"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_HTTP_LMT_CONF |NGX_CONF_TAKE1, ngx_http_access_rule, NGX_HTTP_LOC_CONF_OFFSET, 0, NULL }, { ngx_string("deny"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_HTTP_LMT_CONF |NGX_CONF_TAKE1, ngx_http_access_rule, NGX_HTTP_LOC_CONF_OFFSET, 0, NULL }, ngx_null_command }; static ngx_http_module_t ngx_http_access_module_ctx = { NULL, /* preconfiguration */ ngx_http_access_init, /* postconfiguration */ NULL, /* create main configuration */ NULL, /* init main configuration */ NULL, /* create server configuration */ NULL, /* merge server configuration */ ngx_http_access_create_loc_conf, /* create location configuration */ ngx_http_access_merge_loc_conf /* merge location configuration */ }; ngx_module_t ngx_http_access_module = { NGX_MODULE_V1, &ngx_http_access_module_ctx, /* module context */ ngx_http_access_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_access_handler(ngx_http_request_t *r) { struct sockaddr_in *sin; ngx_http_access_loc_conf_t *alcf; #if (NGX_HAVE_INET6) u_char *p; in_addr_t addr; struct sockaddr_in6 *sin6; #endif alcf = ngx_http_get_module_loc_conf(r, ngx_http_access_module); switch (r->connection->sockaddr->sa_family) { case AF_INET: if (alcf->rules) { sin = (struct sockaddr_in *) r->connection->sockaddr; return ngx_http_access_inet(r, alcf, sin->sin_addr.s_addr); } break; #if (NGX_HAVE_INET6) case AF_INET6: sin6 = (struct sockaddr_in6 *) r->connection->sockaddr; p = sin6->sin6_addr.s6_addr; if (alcf->rules && IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) { addr = p[12] << 24; addr += p[13] << 16; addr += p[14] << 8; addr += p[15]; return ngx_http_access_inet(r, alcf, htonl(addr)); } if (alcf->rules6) { return ngx_http_access_inet6(r, alcf, p); } break; #endif #if (NGX_HAVE_UNIX_DOMAIN) case AF_UNIX: if (alcf->rules_un) { return ngx_http_access_unix(r, alcf); } break; #endif } return NGX_DECLINED; } static ngx_int_t ngx_http_access_inet(ngx_http_request_t *r, ngx_http_access_loc_conf_t *alcf, in_addr_t addr) { ngx_uint_t i; ngx_http_access_rule_t *rule; rule = alcf->rules->elts; for (i = 0; i < alcf->rules->nelts; i++) { ngx_log_debug3(NGX_LOG_DEBUG_HTTP, r->connection->log, 0, "access: %08XD %08XD %08XD", addr, rule[i].mask, rule[i].addr); if ((addr & rule[i].mask) == rule[i].addr) { return ngx_http_access_found(r, rule[i].deny); } } return NGX_DECLINED; } #if (NGX_HAVE_INET6) static ngx_int_t ngx_http_access_inet6(ngx_http_request_t *r, ngx_http_access_loc_conf_t *alcf, u_char *p) { ngx_uint_t n; ngx_uint_t i; ngx_http_access_rule6_t *rule6; rule6 = alcf->rules6->elts; for (i = 0; i < alcf->rules6->nelts; i++) { #if (NGX_DEBUG) { size_t cl, ml, al; u_char ct[NGX_INET6_ADDRSTRLEN]; u_char mt[NGX_INET6_ADDRSTRLEN]; u_char at[NGX_INET6_ADDRSTRLEN]; cl = ngx_inet6_ntop(p, ct, NGX_INET6_ADDRSTRLEN); ml = ngx_inet6_ntop(rule6[i].mask.s6_addr, mt, NGX_INET6_ADDRSTRLEN); al = ngx_inet6_ntop(rule6[i].addr.s6_addr, at, NGX_INET6_ADDRSTRLEN); ngx_log_debug6(NGX_LOG_DEBUG_HTTP, r->connection->log, 0, "access: %*s %*s %*s", cl, ct, ml, mt, al, at); } #endif for (n = 0; n < 16; n++) { if ((p[n] & rule6[i].mask.s6_addr[n]) != rule6[i].addr.s6_addr[n]) { goto next; } } return ngx_http_access_found(r, rule6[i].deny); next: continue; } return NGX_DECLINED; } #endif #if (NGX_HAVE_UNIX_DOMAIN) static ngx_int_t ngx_http_access_unix(ngx_http_request_t *r, ngx_http_access_loc_conf_t *alcf) { ngx_uint_t i; ngx_http_access_rule_un_t *rule_un; rule_un = alcf->rules_un->elts; for (i = 0; i < alcf->rules_un->nelts; i++) { /* TODO: check path */ if (1) { return ngx_http_access_found(r, rule_un[i].deny); } } return NGX_DECLINED; } #endif static ngx_int_t ngx_http_access_found(ngx_http_request_t *r, ngx_uint_t deny) { ngx_http_core_loc_conf_t *clcf; if (deny) { clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module); if (clcf->satisfy == NGX_HTTP_SATISFY_ALL) { ngx_log_error(NGX_LOG_ERR, r->connection->log, 0, "access forbidden by rule"); } return NGX_HTTP_FORBIDDEN; } return NGX_OK; } static char * ngx_http_access_rule(ngx_conf_t *cf, ngx_command_t *cmd, void *conf) { ngx_http_access_loc_conf_t *alcf = conf; ngx_int_t rc; ngx_uint_t all; ngx_str_t *value; ngx_cidr_t cidr; ngx_http_access_rule_t *rule; #if (NGX_HAVE_INET6) ngx_http_access_rule6_t *rule6; #endif #if (NGX_HAVE_UNIX_DOMAIN) ngx_http_access_rule_un_t *rule_un; #endif all = 0; ngx_memzero(&cidr, sizeof(ngx_cidr_t)); value = cf->args->elts; if (value[1].len == 3 && ngx_strcmp(value[1].data, "all") == 0) { all = 1; #if (NGX_HAVE_UNIX_DOMAIN) } else if (value[1].len == 5 && ngx_strcmp(value[1].data, "unix:") == 0) { cidr.family = AF_UNIX; #endif } else { rc = ngx_ptocidr(&value[1], &cidr); if (rc == NGX_ERROR) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "invalid parameter \"%V\"", &value[1]); return NGX_CONF_ERROR; } if (rc == NGX_DONE) { ngx_conf_log_error(NGX_LOG_WARN, cf, 0, "low address bits of %V are meaningless", &value[1]); } } if (cidr.family == AF_INET || all) { if (alcf->rules == NULL) { alcf->rules = ngx_array_create(cf->pool, 4, sizeof(ngx_http_access_rule_t)); if (alcf->rules == NULL) { return NGX_CONF_ERROR; } } rule = ngx_array_push(alcf->rules); if (rule == NULL) { return NGX_CONF_ERROR; } rule->mask = cidr.u.in.mask; rule->addr = cidr.u.in.addr; rule->deny = (value[0].data[0] == 'd') ? 1 : 0; } #if (NGX_HAVE_INET6) if (cidr.family == AF_INET6 || all) { if (alcf->rules6 == NULL) { alcf->rules6 = ngx_array_create(cf->pool, 4, sizeof(ngx_http_access_rule6_t)); if (alcf->rules6 == NULL) { return NGX_CONF_ERROR; } } rule6 = ngx_array_push(alcf->rules6); if (rule6 == NULL) { return NGX_CONF_ERROR; } rule6->mask = cidr.u.in6.mask; rule6->addr = cidr.u.in6.addr; rule6->deny = (value[0].data[0] == 'd') ? 1 : 0; } #endif #if (NGX_HAVE_UNIX_DOMAIN) if (cidr.family == AF_UNIX || all) { if (alcf->rules_un == NULL) { alcf->rules_un = ngx_array_create(cf->pool, 1, sizeof(ngx_http_access_rule_un_t)); if (alcf->rules_un == NULL) { return NGX_CONF_ERROR; } } rule_un = ngx_array_push(alcf->rules_un); if (rule_un == NULL) { return NGX_CONF_ERROR; } rule_un->deny = (value[0].data[0] == 'd') ? 1 : 0; } #endif return NGX_CONF_OK; } static void * ngx_http_access_create_loc_conf(ngx_conf_t *cf) { ngx_http_access_loc_conf_t *conf; conf = ngx_pcalloc(cf->pool, sizeof(ngx_http_access_loc_conf_t)); if (conf == NULL) { return NULL; } return conf; } static char * ngx_http_access_merge_loc_conf(ngx_conf_t *cf, void *parent, void *child) { ngx_http_access_loc_conf_t *prev = parent; ngx_http_access_loc_conf_t *conf = child; if (conf->rules == NULL #if (NGX_HAVE_INET6) && conf->rules6 == NULL #endif #if (NGX_HAVE_UNIX_DOMAIN) && conf->rules_un == NULL #endif ) { conf->rules = prev->rules; #if (NGX_HAVE_INET6) conf->rules6 = prev->rules6; #endif #if (NGX_HAVE_UNIX_DOMAIN) conf->rules_un = prev->rules_un; #endif } return NGX_CONF_OK; } static ngx_int_t ngx_http_access_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_ACCESS_PHASE].handlers); if (h == NULL) { return NGX_ERROR; } *h = ngx_http_access_handler; return NGX_OK; }