Mercurial > hg > nginx
view src/core/ngx_resolver.h @ 6371:33c4d319f08f
Resolver: improved PTR response processing.
The previous code only parsed the first answer, without checking its
type, and required a compressed RR name.
The new code checks the RR type, supports responses with multiple
answers, and doesn't require the RR name to be compressed.
This has a side effect in limited support of CNAME. If a response
includes both CNAME and PTR RRs, like when recursion is enabled on
the server, PTR RR is handled.
Full CNAME support in PTR response is not implemented in this change.
author | Ruslan Ermilov <ru@nginx.com> |
---|---|
date | Thu, 17 Dec 2015 17:21:16 +0300 |
parents | 5a16d40c63de |
children | c94aba230a5a |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #ifndef _NGX_RESOLVER_H_INCLUDED_ #define _NGX_RESOLVER_H_INCLUDED_ #define NGX_RESOLVE_A 1 #define NGX_RESOLVE_CNAME 5 #define NGX_RESOLVE_PTR 12 #define NGX_RESOLVE_MX 15 #define NGX_RESOLVE_TXT 16 #if (NGX_HAVE_INET6) #define NGX_RESOLVE_AAAA 28 #endif #define NGX_RESOLVE_DNAME 39 #define NGX_RESOLVE_FORMERR 1 #define NGX_RESOLVE_SERVFAIL 2 #define NGX_RESOLVE_NXDOMAIN 3 #define NGX_RESOLVE_NOTIMP 4 #define NGX_RESOLVE_REFUSED 5 #define NGX_RESOLVE_TIMEDOUT NGX_ETIMEDOUT #define NGX_NO_RESOLVER (void *) -1 #define NGX_RESOLVER_MAX_RECURSION 50 typedef struct ngx_resolver_s ngx_resolver_t; typedef struct { ngx_connection_t *udp; ngx_connection_t *tcp; struct sockaddr *sockaddr; socklen_t socklen; ngx_str_t server; ngx_log_t log; ngx_buf_t *read_buf; ngx_buf_t *write_buf; ngx_resolver_t *resolver; } ngx_resolver_connection_t; typedef struct ngx_resolver_ctx_s ngx_resolver_ctx_t; typedef void (*ngx_resolver_handler_pt)(ngx_resolver_ctx_t *ctx); typedef struct { ngx_rbtree_node_t node; ngx_queue_t queue; /* PTR: resolved name, A: name to resolve */ u_char *name; #if (NGX_HAVE_INET6) /* PTR: IPv6 address to resolve (IPv4 address is in rbtree node key) */ struct in6_addr addr6; #endif u_short nlen; u_short qlen; u_char *query; #if (NGX_HAVE_INET6) u_char *query6; #endif union { in_addr_t addr; in_addr_t *addrs; u_char *cname; } u; u_char code; u_short naddrs; u_short cnlen; #if (NGX_HAVE_INET6) union { struct in6_addr addr6; struct in6_addr *addrs6; } u6; u_short naddrs6; #endif time_t expire; time_t valid; uint32_t ttl; unsigned tcp:1; #if (NGX_HAVE_INET6) unsigned tcp6:1; #endif ngx_uint_t last_connection; ngx_resolver_ctx_t *waiting; } ngx_resolver_node_t; struct ngx_resolver_s { /* has to be pointer because of "incomplete type" */ ngx_event_t *event; void *dummy; ngx_log_t *log; /* event ident must be after 3 pointers as in ngx_connection_t */ ngx_int_t ident; /* simple round robin DNS peers balancer */ ngx_array_t connections; ngx_uint_t last_connection; ngx_rbtree_t name_rbtree; ngx_rbtree_node_t name_sentinel; ngx_rbtree_t addr_rbtree; ngx_rbtree_node_t addr_sentinel; ngx_queue_t name_resend_queue; ngx_queue_t addr_resend_queue; ngx_queue_t name_expire_queue; ngx_queue_t addr_expire_queue; #if (NGX_HAVE_INET6) ngx_uint_t ipv6; /* unsigned ipv6:1; */ ngx_rbtree_t addr6_rbtree; ngx_rbtree_node_t addr6_sentinel; ngx_queue_t addr6_resend_queue; ngx_queue_t addr6_expire_queue; #endif time_t resend_timeout; time_t tcp_timeout; time_t expire; time_t valid; ngx_uint_t log_level; }; struct ngx_resolver_ctx_s { ngx_resolver_ctx_t *next; ngx_resolver_t *resolver; ngx_resolver_node_t *node; /* event ident must be after 3 pointers as in ngx_connection_t */ ngx_int_t ident; ngx_int_t state; ngx_str_t name; ngx_uint_t naddrs; ngx_addr_t *addrs; ngx_addr_t addr; struct sockaddr_in sin; ngx_resolver_handler_pt handler; void *data; ngx_msec_t timeout; ngx_uint_t quick; /* unsigned quick:1; */ ngx_uint_t recursion; ngx_event_t *event; }; ngx_resolver_t *ngx_resolver_create(ngx_conf_t *cf, ngx_str_t *names, ngx_uint_t n); ngx_resolver_ctx_t *ngx_resolve_start(ngx_resolver_t *r, ngx_resolver_ctx_t *temp); ngx_int_t ngx_resolve_name(ngx_resolver_ctx_t *ctx); void ngx_resolve_name_done(ngx_resolver_ctx_t *ctx); ngx_int_t ngx_resolve_addr(ngx_resolver_ctx_t *ctx); void ngx_resolve_addr_done(ngx_resolver_ctx_t *ctx); char *ngx_resolver_strerror(ngx_int_t err); #endif /* _NGX_RESOLVER_H_INCLUDED_ */