| /* |
| * Copyright (C) 2014 The Android Open Source Project |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * * Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * * Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in |
| * the documentation and/or other materials provided with the |
| * distribution. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS |
| * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE |
| * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, |
| * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, |
| * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS |
| * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED |
| * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, |
| * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT |
| * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| * SUCH DAMAGE. |
| */ |
| |
| #pragma once |
| |
| #include "params.h" |
| |
| #include <arpa/nameser.h> |
| #include <netinet/in.h> |
| |
| /* |
| * Passing NETID_UNSET as the netId causes system/netd/resolv/DnsProxyListener.cpp to |
| * fill in the appropriate default netId for the query. |
| */ |
| #define NETID_UNSET 0u |
| |
| /* |
| * MARK_UNSET represents the default (i.e. unset) value for a socket mark. |
| */ |
| #define MARK_UNSET 0u |
| |
| #define NET_CONTEXT_INVALID_UID ((uid_t)-1) |
| #define NET_CONTEXT_INVALID_PID ((pid_t)-1) |
| |
| /* |
| * A struct to capture context relevant to network operations. |
| * |
| * Application and DNS netids/marks can differ from one another under certain |
| * circumstances, notably when a VPN applies to the given uid's traffic but the |
| * VPN network does not have its own DNS servers explicitly provisioned. |
| * |
| * The introduction of per-UID routing means the uid is also an essential part |
| * of the evaluation context. Its proper uninitialized value is |
| * NET_CONTEXT_INVALID_UID. |
| */ |
| struct android_net_context { |
| unsigned app_netid; |
| unsigned app_mark; |
| unsigned dns_netid; |
| unsigned dns_mark; |
| uid_t uid = NET_CONTEXT_INVALID_UID; |
| unsigned flags; |
| // Variable to store the pid of the application sending DNS query. |
| pid_t pid = NET_CONTEXT_INVALID_PID; |
| }; |
| |
| #define NET_CONTEXT_FLAG_USE_LOCAL_NAMESERVERS 0x00000001 |
| #define NET_CONTEXT_FLAG_USE_EDNS 0x00000002 |
| #define NET_CONTEXT_FLAG_USE_DNS_OVER_TLS 0x00000004 |
| |
| // TODO: investigate having the resolver check permissions itself, either by adding support to |
| // libbinder_ndk or by converting IPermissionController into a stable AIDL interface. |
| typedef bool (*check_calling_permission_callback)(const char* permission); |
| typedef void (*get_network_context_callback)(unsigned netid, uid_t uid, |
| android_net_context* netcontext); |
| typedef void (*log_callback)(const char* msg); |
| typedef int (*tagSocketCallback)(int sockFd, uint32_t tag, uid_t uid, pid_t pid); |
| |
| /* |
| * Some functions needed by the resolver (e.g. checkCallingPermission()) live in |
| * libraries with no ABI stability guarantees, such as libbinder.so. |
| * As a temporary workaround, we keep these functions in netd and call them via |
| * function pointers. |
| */ |
| struct ResolverNetdCallbacks { |
| check_calling_permission_callback check_calling_permission; |
| get_network_context_callback get_network_context; |
| log_callback log; |
| tagSocketCallback tagSocket; |
| }; |
| |
| #define TAG_SYSTEM_DNS 0xFFFFFF82 |
| |
| LIBNETD_RESOLV_PUBLIC bool resolv_has_nameservers(unsigned netid); |
| |
| // Set callbacks and bring DnsResolver up. |
| LIBNETD_RESOLV_PUBLIC bool resolv_init(const ResolverNetdCallbacks* callbacks); |
| |
| // Function that performs RDNS in local cache. The |domain_name_size| is the size of domain_name |
| // buffer, which is recommended to NS_MAXDNAME. Function return false if hostname not found or |
| // domain_name_size > NS_MAXDNAME. |
| LIBNETD_RESOLV_PUBLIC bool resolv_gethostbyaddr_from_local_cache(unsigned netId, char domain_name[], |
| unsigned domain_name_size, |
| char* ip_address); |