1 /* 2 * Copyright (C) 2014 The Android Open Source Project 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in 12 * the documentation and/or other materials provided with the 13 * distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 #ifndef _RESOLV_NETID_H 29 #define _RESOLV_NETID_H 30 31 /* This header contains declarations related to per-network DNS 32 * server selection. They are used by system/netd/ and should not be 33 * exposed by the C library's public NDK headers. 34 */ 35 #include <sys/cdefs.h> 36 #include <netinet/in.h> 37 #include "resolv_params.h" 38 #include <stdio.h> 39 40 /* 41 * Passing NETID_UNSET as the netId causes system/netd/server/DnsProxyListener.cpp to 42 * fill in the appropriate default netId for the query. 43 */ 44 #define NETID_UNSET 0u 45 46 /* 47 * MARK_UNSET represents the default (i.e. unset) value for a socket mark. 48 */ 49 #define MARK_UNSET 0u 50 51 __BEGIN_DECLS 52 53 struct __res_params; 54 struct addrinfo; 55 56 #define __used_in_netd __attribute__((visibility ("default"))) 57 58 /* 59 * A struct to capture context relevant to network operations. 60 * 61 * Application and DNS netids/marks can differ from one another under certain 62 * circumstances, notably when a VPN applies to the given uid's traffic but the 63 * VPN network does not have its own DNS servers explicitly provisioned. 64 * 65 * The introduction of per-UID routing means the uid is also an essential part 66 * of the evaluation context. Its proper uninitialized value is 67 * NET_CONTEXT_INVALID_UID. 68 */ 69 struct android_net_context { 70 unsigned app_netid; 71 unsigned app_mark; 72 unsigned dns_netid; 73 unsigned dns_mark; 74 uid_t uid; 75 unsigned flags; 76 res_send_qhook qhook; 77 }; 78 79 #define NET_CONTEXT_INVALID_UID ((uid_t)-1) 80 81 #define NET_CONTEXT_FLAG_USE_LOCAL_NAMESERVERS 0x00000001 82 #define NET_CONTEXT_FLAG_USE_EDNS 0x00000002 83 84 struct hostent *android_gethostbyaddrfornet(const void *, socklen_t, int, unsigned, unsigned) __used_in_netd; 85 struct hostent *android_gethostbynamefornet(const char *, int, unsigned, unsigned) __used_in_netd; 86 int android_getaddrinfofornet(const char *, const char *, const struct addrinfo *, unsigned, 87 unsigned, struct addrinfo **) __used_in_netd; 88 /* 89 * TODO: consider refactoring android_getaddrinfo_proxy() to serve as an 90 * explore_fqdn() dispatch table method, with the below function only making DNS calls. 91 */ 92 struct hostent *android_gethostbyaddrfornetcontext(const void *, socklen_t, int, const struct android_net_context *) __used_in_netd; 93 struct hostent *android_gethostbynamefornetcontext(const char *, int, const struct android_net_context *) __used_in_netd; 94 int android_getaddrinfofornetcontext(const char *, const char *, const struct addrinfo *, 95 const struct android_net_context *, struct addrinfo **) __used_in_netd; 96 97 /* set name servers for a network */ 98 extern int _resolv_set_nameservers_for_net(unsigned netid, const char** servers, 99 unsigned numservers, const char *domains, const struct __res_params* params) __used_in_netd; 100 101 /* flush the cache associated with a certain network */ 102 extern void _resolv_flush_cache_for_net(unsigned netid) __used_in_netd; 103 104 /* delete the cache associated with a certain network */ 105 extern void _resolv_delete_cache_for_net(unsigned netid) __used_in_netd; 106 107 /* Internal use only. */ 108 struct hostent *android_gethostbyaddrfornetcontext_proxy(const void *, socklen_t, int , const struct android_net_context *) __LIBC_HIDDEN__; 109 int android_getnameinfofornet(const struct sockaddr *, socklen_t, char *, size_t, char *, size_t, int, unsigned, unsigned) __LIBC_HIDDEN__; 110 111 __END_DECLS 112 113 #endif /* _RESOLV_NETID_H */ 114