view src/http/ngx_http_variables.h @ 7119:fef61d26da39

Fixed buffer overread with unix sockets after accept(). Some OSes (notably macOS, NetBSD, and Solaris) allow unix socket addresses larger than struct sockaddr_un. Moreover, some of them (macOS, Solaris) return socklen of the socket address before it was truncated to fit the buffer provided. As such, on these systems socklen must not be used without additional check that it is within the buffer provided. Appropriate checks added to ngx_event_accept() (after accept()), ngx_event_recvmsg() (after recvmsg()), and ngx_set_inherited_sockets() (after getsockname()). We also obtain socket addresses via getsockname() in ngx_connection_local_sockaddr(), but it does not need any checks as it is only used for INET and INET6 sockets (as there can be no wildcard unix sockets).
author Maxim Dounin <mdounin@mdounin.ru>
date Wed, 04 Oct 2017 21:19:33 +0300
parents 2a288909abc6
children 08b3ea81ff5f
line wrap: on
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/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


#ifndef _NGX_HTTP_VARIABLES_H_INCLUDED_
#define _NGX_HTTP_VARIABLES_H_INCLUDED_


#include <ngx_config.h>
#include <ngx_core.h>
#include <ngx_http.h>


typedef ngx_variable_value_t  ngx_http_variable_value_t;

#define ngx_http_variable(v)     { sizeof(v) - 1, 1, 0, 0, 0, (u_char *) v }

typedef struct ngx_http_variable_s  ngx_http_variable_t;

typedef void (*ngx_http_set_variable_pt) (ngx_http_request_t *r,
    ngx_http_variable_value_t *v, uintptr_t data);
typedef ngx_int_t (*ngx_http_get_variable_pt) (ngx_http_request_t *r,
    ngx_http_variable_value_t *v, uintptr_t data);


#define NGX_HTTP_VAR_CHANGEABLE   1
#define NGX_HTTP_VAR_NOCACHEABLE  2
#define NGX_HTTP_VAR_INDEXED      4
#define NGX_HTTP_VAR_NOHASH       8
#define NGX_HTTP_VAR_WEAK         16
#define NGX_HTTP_VAR_PREFIX       32


struct ngx_http_variable_s {
    ngx_str_t                     name;   /* must be first to build the hash */
    ngx_http_set_variable_pt      set_handler;
    ngx_http_get_variable_pt      get_handler;
    uintptr_t                     data;
    ngx_uint_t                    flags;
    ngx_uint_t                    index;
};

#define ngx_http_null_variable  { ngx_null_string, NULL, NULL, 0, 0, 0 }


ngx_http_variable_t *ngx_http_add_variable(ngx_conf_t *cf, ngx_str_t *name,
    ngx_uint_t flags);
ngx_int_t ngx_http_get_variable_index(ngx_conf_t *cf, ngx_str_t *name);
ngx_http_variable_value_t *ngx_http_get_indexed_variable(ngx_http_request_t *r,
    ngx_uint_t index);
ngx_http_variable_value_t *ngx_http_get_flushed_variable(ngx_http_request_t *r,
    ngx_uint_t index);

ngx_http_variable_value_t *ngx_http_get_variable(ngx_http_request_t *r,
    ngx_str_t *name, ngx_uint_t key);

ngx_int_t ngx_http_variable_unknown_header(ngx_http_variable_value_t *v,
    ngx_str_t *var, ngx_list_part_t *part, size_t prefix);


#if (NGX_PCRE)

typedef struct {
    ngx_uint_t                    capture;
    ngx_int_t                     index;
} ngx_http_regex_variable_t;


typedef struct {
    ngx_regex_t                  *regex;
    ngx_uint_t                    ncaptures;
    ngx_http_regex_variable_t    *variables;
    ngx_uint_t                    nvariables;
    ngx_str_t                     name;
} ngx_http_regex_t;


typedef struct {
    ngx_http_regex_t             *regex;
    void                         *value;
} ngx_http_map_regex_t;


ngx_http_regex_t *ngx_http_regex_compile(ngx_conf_t *cf,
    ngx_regex_compile_t *rc);
ngx_int_t ngx_http_regex_exec(ngx_http_request_t *r, ngx_http_regex_t *re,
    ngx_str_t *s);

#endif


typedef struct {
    ngx_hash_combined_t           hash;
#if (NGX_PCRE)
    ngx_http_map_regex_t         *regex;
    ngx_uint_t                    nregex;
#endif
} ngx_http_map_t;


void *ngx_http_map_find(ngx_http_request_t *r, ngx_http_map_t *map,
    ngx_str_t *match);


ngx_int_t ngx_http_variables_add_core_vars(ngx_conf_t *cf);
ngx_int_t ngx_http_variables_init_vars(ngx_conf_t *cf);


extern ngx_http_variable_value_t  ngx_http_variable_null_value;
extern ngx_http_variable_value_t  ngx_http_variable_true_value;


#endif /* _NGX_HTTP_VARIABLES_H_INCLUDED_ */