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Sreeram Ramachandran5c181bf2014-04-07 14:10:04 -07001/*
2 * Copyright (C) 2014 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include "RouteController.h"
18
19#include "Fwmark.h"
Sreeram Ramachandranb1425cc2014-06-23 18:54:27 -070020#include "UidRanges.h"
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -070021
22#define LOG_TAG "Netd"
23#include "log/log.h"
24#include "logwrap/logwrap.h"
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -070025#include "resolv_netid.h"
Sreeram Ramachandran5c181bf2014-04-07 14:10:04 -070026
Lorenzo Colittiba25df92014-06-18 00:22:17 +090027#include <arpa/inet.h>
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -070028#include <fcntl.h>
Lorenzo Colitti4753afd2014-06-20 23:03:29 +090029#include <linux/fib_rules.h>
Paul Jensena561e122014-06-12 16:46:37 -040030#include <map>
Sreeram Ramachandran5c181bf2014-04-07 14:10:04 -070031#include <net/if.h>
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -070032#include <sys/stat.h>
Sreeram Ramachandran5c181bf2014-04-07 14:10:04 -070033
34namespace {
35
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -070036// BEGIN CONSTANTS --------------------------------------------------------------------------------
37
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -070038const uint32_t RULE_PRIORITY_VPN_OVERRIDE_SYSTEM = 10000;
39// const uint32_t RULE_PRIORITY_VPN_OVERRIDE_LOCAL = 11000;
40const uint32_t RULE_PRIORITY_SECURE_VPN = 12000;
41const uint32_t RULE_PRIORITY_EXPLICIT_NETWORK = 13000;
42const uint32_t RULE_PRIORITY_OUTPUT_INTERFACE = 14000;
43const uint32_t RULE_PRIORITY_LEGACY_SYSTEM = 15000;
44const uint32_t RULE_PRIORITY_LEGACY_NETWORK = 16000;
Sreeram Ramachandran6a773532014-07-11 09:10:20 -070045const uint32_t RULE_PRIORITY_LOCAL_NETWORK = 17000;
Sreeram Ramachandran87475a12014-07-15 16:20:28 -070046const uint32_t RULE_PRIORITY_TETHERING = 18000;
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -070047const uint32_t RULE_PRIORITY_IMPLICIT_NETWORK = 19000;
48// const uint32_t RULE_PRIORITY_BYPASSABLE_VPN = 20000;
49// const uint32_t RULE_PRIORITY_VPN_FALLTHROUGH = 21000;
50const uint32_t RULE_PRIORITY_DEFAULT_NETWORK = 22000;
51const uint32_t RULE_PRIORITY_DIRECTLY_CONNECTED = 23000;
52const uint32_t RULE_PRIORITY_UNREACHABLE = 24000;
Sreeram Ramachandran5c181bf2014-04-07 14:10:04 -070053
Sreeram Ramachandran87475a12014-07-15 16:20:28 -070054const uint32_t ROUTE_TABLE_LOCAL_NETWORK = 97;
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -070055const uint32_t ROUTE_TABLE_LEGACY_NETWORK = 98;
56const uint32_t ROUTE_TABLE_LEGACY_SYSTEM = 99;
57
Sreeram Ramachandran87475a12014-07-15 16:20:28 -070058const char* const ROUTE_TABLE_NAME_LOCAL_NETWORK = "local_network";
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -070059const char* const ROUTE_TABLE_NAME_LEGACY_NETWORK = "legacy_network";
60const char* const ROUTE_TABLE_NAME_LEGACY_SYSTEM = "legacy_system";
61
Sreeram Ramachandranbb40d512014-07-11 11:45:14 -070062const char* const ROUTE_TABLE_NAME_LOCAL = "local";
63const char* const ROUTE_TABLE_NAME_MAIN = "main";
64
Lorenzo Colitti59656512014-06-25 03:20:29 +090065// TODO: These values aren't defined by the Linux kernel, because our UID routing changes are not
66// upstream (yet?), so we can't just pick them up from kernel headers. When (if?) the changes make
67// it upstream, we'll remove this and rely on the kernel header values. For now, add a static assert
68// that will warn us if upstream has given these values some other meaning.
69const uint16_t FRA_UID_START = 18;
70const uint16_t FRA_UID_END = 19;
71static_assert(FRA_UID_START > FRA_MAX,
72 "Android-specific FRA_UID_{START,END} values also assigned in Linux uapi. "
73 "Check that these values match what the kernel does and then update this assertion.");
74
Lorenzo Colitti72723682014-06-26 13:51:10 +090075const uint16_t NETLINK_REQUEST_FLAGS = NLM_F_REQUEST | NLM_F_ACK;
76const uint16_t NETLINK_CREATE_REQUEST_FLAGS = NETLINK_REQUEST_FLAGS | NLM_F_CREATE | NLM_F_EXCL;
Lorenzo Colitti4753afd2014-06-20 23:03:29 +090077
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -070078const sockaddr_nl NETLINK_ADDRESS = {AF_NETLINK, 0, 0, 0};
79
80const uint8_t AF_FAMILIES[] = {AF_INET, AF_INET6};
81
82const char* const IP_VERSIONS[] = {"-4", "-6"};
83
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -070084const uid_t UID_ROOT = 0;
Sreeram Ramachandran87475a12014-07-15 16:20:28 -070085const char* const IIF_NONE = NULL;
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -070086const char* const OIF_NONE = NULL;
87const bool ACTION_ADD = true;
88const bool ACTION_DEL = false;
89const bool MODIFY_NON_UID_BASED_RULES = true;
90
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -070091const char* const RT_TABLES_PATH = "/data/misc/net/rt_tables";
Sreeram Ramachandranc7d804c2014-07-09 07:39:30 -070092const int RT_TABLES_FLAGS = O_CREAT | O_TRUNC | O_WRONLY | O_NOFOLLOW | O_CLOEXEC;
93const mode_t RT_TABLES_MODE = S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH; // mode 0644, rw-r--r--
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -070094
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -070095// Avoids "non-constant-expression cannot be narrowed from type 'unsigned int' to 'unsigned short'"
96// warnings when using RTA_LENGTH(x) inside static initializers (even when x is already uint16_t).
97constexpr uint16_t U16_RTA_LENGTH(uint16_t x) {
98 return RTA_LENGTH(x);
99}
100
101// These are practically const, but can't be declared so, because they are used to initialize
102// non-const pointers ("void* iov_base") in iovec arrays.
103rtattr FRATTR_PRIORITY = { U16_RTA_LENGTH(sizeof(uint32_t)), FRA_PRIORITY };
104rtattr FRATTR_TABLE = { U16_RTA_LENGTH(sizeof(uint32_t)), FRA_TABLE };
105rtattr FRATTR_FWMARK = { U16_RTA_LENGTH(sizeof(uint32_t)), FRA_FWMARK };
106rtattr FRATTR_FWMASK = { U16_RTA_LENGTH(sizeof(uint32_t)), FRA_FWMASK };
107rtattr FRATTR_UID_START = { U16_RTA_LENGTH(sizeof(uid_t)), FRA_UID_START };
108rtattr FRATTR_UID_END = { U16_RTA_LENGTH(sizeof(uid_t)), FRA_UID_END };
109
110rtattr RTATTR_TABLE = { U16_RTA_LENGTH(sizeof(uint32_t)), RTA_TABLE };
111rtattr RTATTR_OIF = { U16_RTA_LENGTH(sizeof(uint32_t)), RTA_OIF };
112
113uint8_t PADDING_BUFFER[RTA_ALIGNTO] = {0, 0, 0, 0};
114
115// END CONSTANTS ----------------------------------------------------------------------------------
116
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -0700117// No locks needed because RouteController is accessed only from one thread (in CommandListener).
118std::map<std::string, uint32_t> interfaceToTable;
Paul Jensena561e122014-06-12 16:46:37 -0400119
Sreeram Ramachandran5c181bf2014-04-07 14:10:04 -0700120uint32_t getRouteTableForInterface(const char* interface) {
Sreeram Ramachandrana4811802014-04-10 12:10:24 -0700121 uint32_t index = if_nametoindex(interface);
Paul Jensena561e122014-06-12 16:46:37 -0400122 if (index) {
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -0700123 index += RouteController::ROUTE_TABLE_OFFSET_FROM_INDEX;
124 interfaceToTable[interface] = index;
125 return index;
Paul Jensena561e122014-06-12 16:46:37 -0400126 }
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -0700127 // If the interface goes away if_nametoindex() will return 0 but we still need to know
128 // the index so we can remove the rules and routes.
129 auto iter = interfaceToTable.find(interface);
130 if (iter == interfaceToTable.end()) {
131 ALOGE("cannot find interface %s", interface);
132 return RT_TABLE_UNSPEC;
133 }
134 return iter->second;
135}
136
137void addTableName(uint32_t table, const std::string& name, std::string* contents) {
138 char tableString[UINT32_STRLEN];
139 snprintf(tableString, sizeof(tableString), "%u", table);
140 *contents += tableString;
141 *contents += " ";
142 *contents += name;
143 *contents += "\n";
144}
145
146// Doesn't return success/failure as the file is optional; it's okay if we fail to update it.
147void updateTableNamesFile() {
148 std::string contents;
Sreeram Ramachandranbb40d512014-07-11 11:45:14 -0700149
150 addTableName(RT_TABLE_LOCAL, ROUTE_TABLE_NAME_LOCAL, &contents);
151 addTableName(RT_TABLE_MAIN, ROUTE_TABLE_NAME_MAIN, &contents);
152
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700153 addTableName(ROUTE_TABLE_LOCAL_NETWORK, ROUTE_TABLE_NAME_LOCAL_NETWORK, &contents);
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -0700154 addTableName(ROUTE_TABLE_LEGACY_NETWORK, ROUTE_TABLE_NAME_LEGACY_NETWORK, &contents);
155 addTableName(ROUTE_TABLE_LEGACY_SYSTEM, ROUTE_TABLE_NAME_LEGACY_SYSTEM, &contents);
Sreeram Ramachandranbb40d512014-07-11 11:45:14 -0700156
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -0700157 for (const auto& entry : interfaceToTable) {
158 addTableName(entry.second, entry.first, &contents);
159 }
160
Sreeram Ramachandranc7d804c2014-07-09 07:39:30 -0700161 int fd = open(RT_TABLES_PATH, RT_TABLES_FLAGS, RT_TABLES_MODE);
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -0700162 if (fd == -1) {
163 ALOGE("failed to create %s (%s)", RT_TABLES_PATH, strerror(errno));
164 return;
165 }
166 // File creation is affected by umask, so make sure the right mode bits are set.
Sreeram Ramachandranc7d804c2014-07-09 07:39:30 -0700167 if (fchmod(fd, RT_TABLES_MODE) == -1) {
168 ALOGE("failed to set mode 0%o on %s (%s)", RT_TABLES_MODE, RT_TABLES_PATH, strerror(errno));
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -0700169 }
170 ssize_t bytesWritten = write(fd, contents.data(), contents.size());
171 if (bytesWritten != static_cast<ssize_t>(contents.size())) {
172 ALOGE("failed to write to %s (%zd vs %zu bytes) (%s)", RT_TABLES_PATH, bytesWritten,
173 contents.size(), strerror(errno));
174 }
175 close(fd);
Sreeram Ramachandran5c181bf2014-04-07 14:10:04 -0700176}
177
Lorenzo Colitti4753afd2014-06-20 23:03:29 +0900178// Sends a netlink request and expects an ack.
179// |iov| is an array of struct iovec that contains the netlink message payload.
180// The netlink header is generated by this function based on |action| and |flags|.
181// Returns -errno if there was an error or if the kernel reported an error.
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700182WARN_UNUSED_RESULT int sendNetlinkRequest(uint16_t action, uint16_t flags, iovec* iov, int iovlen) {
Lorenzo Colitti4753afd2014-06-20 23:03:29 +0900183 nlmsghdr nlmsg = {
184 .nlmsg_type = action,
185 .nlmsg_flags = flags,
186 };
187 iov[0].iov_base = &nlmsg;
188 iov[0].iov_len = sizeof(nlmsg);
189 for (int i = 0; i < iovlen; ++i) {
190 nlmsg.nlmsg_len += iov[i].iov_len;
191 }
192
193 int ret;
194 struct {
195 nlmsghdr msg;
196 nlmsgerr err;
197 } response;
198
Lorenzo Colitti4753afd2014-06-20 23:03:29 +0900199 int sock = socket(AF_NETLINK, SOCK_DGRAM, NETLINK_ROUTE);
200 if (sock != -1 &&
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700201 connect(sock, reinterpret_cast<const sockaddr*>(&NETLINK_ADDRESS),
202 sizeof(NETLINK_ADDRESS)) != -1 &&
Lorenzo Colitti4753afd2014-06-20 23:03:29 +0900203 writev(sock, iov, iovlen) != -1 &&
204 (ret = recv(sock, &response, sizeof(response), 0)) != -1) {
205 if (ret == sizeof(response)) {
206 ret = response.err.error; // Netlink errors are negative errno.
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700207 if (ret) {
208 ALOGE("netlink response contains error (%s)", strerror(-ret));
209 }
Lorenzo Colitti4753afd2014-06-20 23:03:29 +0900210 } else {
Sreeram Ramachandran1201e842014-07-01 15:06:05 -0700211 ALOGE("bad netlink response message size (%d != %zu)", ret, sizeof(response));
Lorenzo Colitti4753afd2014-06-20 23:03:29 +0900212 ret = -EBADMSG;
213 }
214 } else {
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700215 ALOGE("netlink socket/connect/writev/recv failed (%s)", strerror(errno));
Lorenzo Colitti4753afd2014-06-20 23:03:29 +0900216 ret = -errno;
217 }
218
219 if (sock != -1) {
220 close(sock);
221 }
222
223 return ret;
224}
225
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700226// Returns 0 on success or negative errno on failure.
227int padInterfaceName(const char* input, char* name, size_t* length, uint16_t* padding) {
228 if (!input) {
229 *length = 0;
230 *padding = 0;
231 return 0;
232 }
233 *length = strlcpy(name, input, IFNAMSIZ) + 1;
234 if (*length > IFNAMSIZ) {
235 ALOGE("interface name too long (%zu > %u)", *length, IFNAMSIZ);
236 return -ENAMETOOLONG;
237 }
238 *padding = RTA_SPACE(*length) - RTA_LENGTH(*length);
239 return 0;
240}
241
Sreeram Ramachandran8fe9c8e2014-04-16 12:08:05 -0700242// Adds or removes a routing rule for IPv4 and IPv6.
243//
244// + If |table| is non-zero, the rule points at the specified routing table. Otherwise, the rule
245// returns ENETUNREACH.
246// + If |mask| is non-zero, the rule matches the specified fwmark and mask. Otherwise, |fwmark| is
247// ignored.
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700248// + If |iif| is non-NULL, the rule matches the specified incoming interface.
249// + If |oif| is non-NULL, the rule matches the specified outgoing interface.
250// + If |uidStart| and |uidEnd| are not INVALID_UID, the rule matches packets from UIDs in that
251// range (inclusive). Otherwise, the rule matches packets from all UIDs.
Lorenzo Colitti96f261e2014-06-23 15:09:54 +0900252//
253// Returns 0 on success or negative errno on failure.
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700254WARN_UNUSED_RESULT int modifyIpRule(uint16_t action, uint32_t priority, uint32_t table,
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700255 uint32_t fwmark, uint32_t mask, const char* iif,
256 const char* oif, uid_t uidStart, uid_t uidEnd) {
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700257 // Ensure that if you set a bit in the fwmark, it's not being ignored by the mask.
258 if (fwmark & ~mask) {
259 ALOGE("mask 0x%x does not select all the bits set in fwmark 0x%x", mask, fwmark);
260 return -ERANGE;
261 }
262
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700263 // Interface names must include exactly one terminating NULL and be properly padded, or older
Lorenzo Colitti4753afd2014-06-20 23:03:29 +0900264 // kernels will refuse to delete rules.
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700265 char iifName[IFNAMSIZ], oifName[IFNAMSIZ];
266 size_t iifLength, oifLength;
267 uint16_t iifPadding, oifPadding;
268 if (int ret = padInterfaceName(iif, iifName, &iifLength, &iifPadding)) {
269 return ret;
270 }
271 if (int ret = padInterfaceName(oif, oifName, &oifLength, &oifPadding)) {
272 return ret;
Lorenzo Colitti4753afd2014-06-20 23:03:29 +0900273 }
274
Lorenzo Colitti59656512014-06-25 03:20:29 +0900275 // Either both start and end UID must be specified, or neither.
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700276 if ((uidStart == INVALID_UID) != (uidEnd == INVALID_UID)) {
Sreeram Ramachandrancf891382014-07-01 15:49:20 -0700277 ALOGE("incompatible start and end UIDs (%u vs %u)", uidStart, uidEnd);
Lorenzo Colitti59656512014-06-25 03:20:29 +0900278 return -EUSERS;
279 }
Lorenzo Colitti72723682014-06-26 13:51:10 +0900280 bool isUidRule = (uidStart != INVALID_UID);
Lorenzo Colitti59656512014-06-25 03:20:29 +0900281
Lorenzo Colitti4753afd2014-06-20 23:03:29 +0900282 // Assemble a rule request and put it in an array of iovec structures.
283 fib_rule_hdr rule = {
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700284 .action = static_cast<uint8_t>(table != RT_TABLE_UNSPEC ? FR_ACT_TO_TBL :
285 FR_ACT_UNREACHABLE),
Lorenzo Colitti4753afd2014-06-20 23:03:29 +0900286 };
287
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700288 rtattr fraIifName = { U16_RTA_LENGTH(iifLength), FRA_IIFNAME };
289 rtattr fraOifName = { U16_RTA_LENGTH(oifLength), FRA_OIFNAME };
Lorenzo Colitti4753afd2014-06-20 23:03:29 +0900290
291 iovec iov[] = {
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700292 { NULL, 0 },
293 { &rule, sizeof(rule) },
294 { &FRATTR_PRIORITY, sizeof(FRATTR_PRIORITY) },
295 { &priority, sizeof(priority) },
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700296 { &FRATTR_TABLE, table != RT_TABLE_UNSPEC ? sizeof(FRATTR_TABLE) : 0 },
297 { &table, table != RT_TABLE_UNSPEC ? sizeof(table) : 0 },
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700298 { &FRATTR_FWMARK, mask ? sizeof(FRATTR_FWMARK) : 0 },
299 { &fwmark, mask ? sizeof(fwmark) : 0 },
300 { &FRATTR_FWMASK, mask ? sizeof(FRATTR_FWMASK) : 0 },
301 { &mask, mask ? sizeof(mask) : 0 },
302 { &FRATTR_UID_START, isUidRule ? sizeof(FRATTR_UID_START) : 0 },
303 { &uidStart, isUidRule ? sizeof(uidStart) : 0 },
304 { &FRATTR_UID_END, isUidRule ? sizeof(FRATTR_UID_END) : 0 },
305 { &uidEnd, isUidRule ? sizeof(uidEnd) : 0 },
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700306 { &fraIifName, iif != IIF_NONE ? sizeof(fraIifName) : 0 },
307 { iifName, iifLength },
308 { PADDING_BUFFER, iifPadding },
309 { &fraOifName, oif != OIF_NONE ? sizeof(fraOifName) : 0 },
310 { oifName, oifLength },
311 { PADDING_BUFFER, oifPadding },
Lorenzo Colitti4753afd2014-06-20 23:03:29 +0900312 };
313
Lorenzo Colitti72723682014-06-26 13:51:10 +0900314 uint16_t flags = (action == RTM_NEWRULE) ? NETLINK_CREATE_REQUEST_FLAGS : NETLINK_REQUEST_FLAGS;
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700315 for (size_t i = 0; i < ARRAY_SIZE(AF_FAMILIES); ++i) {
316 rule.family = AF_FAMILIES[i];
317 if (int ret = sendNetlinkRequest(action, flags, iov, ARRAY_SIZE(iov))) {
Lorenzo Colitti96f261e2014-06-23 15:09:54 +0900318 return ret;
Sreeram Ramachandran5c181bf2014-04-07 14:10:04 -0700319 }
320 }
321
Lorenzo Colitti96f261e2014-06-23 15:09:54 +0900322 return 0;
Sreeram Ramachandran5c181bf2014-04-07 14:10:04 -0700323}
324
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700325WARN_UNUSED_RESULT int modifyIpRule(uint16_t action, uint32_t priority, uint32_t table,
326 uint32_t fwmark, uint32_t mask) {
327 return modifyIpRule(action, priority, table, fwmark, mask, IIF_NONE, OIF_NONE, INVALID_UID,
328 INVALID_UID);
329}
330
Lorenzo Colittiba25df92014-06-18 00:22:17 +0900331// Adds or deletes an IPv4 or IPv6 route.
332// Returns 0 on success or negative errno on failure.
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700333WARN_UNUSED_RESULT int modifyIpRoute(uint16_t action, uint32_t table, const char* interface,
334 const char* destination, const char* nexthop) {
Lorenzo Colittiba25df92014-06-18 00:22:17 +0900335 // At least the destination must be non-null.
336 if (!destination) {
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700337 ALOGE("null destination");
Lorenzo Colittiba25df92014-06-18 00:22:17 +0900338 return -EFAULT;
339 }
Sreeram Ramachandran7619e1b2014-04-15 14:23:08 -0700340
Lorenzo Colittiba25df92014-06-18 00:22:17 +0900341 // Parse the prefix.
342 uint8_t rawAddress[sizeof(in6_addr)];
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700343 uint8_t family;
344 uint8_t prefixLength;
Lorenzo Colittiba25df92014-06-18 00:22:17 +0900345 int rawLength = parsePrefix(destination, &family, rawAddress, sizeof(rawAddress),
346 &prefixLength);
347 if (rawLength < 0) {
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700348 ALOGE("parsePrefix failed for destination %s (%s)", destination, strerror(-rawLength));
Lorenzo Colittiba25df92014-06-18 00:22:17 +0900349 return rawLength;
350 }
Sreeram Ramachandran7619e1b2014-04-15 14:23:08 -0700351
Lorenzo Colittiba25df92014-06-18 00:22:17 +0900352 if (static_cast<size_t>(rawLength) > sizeof(rawAddress)) {
Sreeram Ramachandran1201e842014-07-01 15:06:05 -0700353 ALOGE("impossible! address too long (%d vs %zu)", rawLength, sizeof(rawAddress));
Lorenzo Colittiba25df92014-06-18 00:22:17 +0900354 return -ENOBUFS; // Cannot happen; parsePrefix only supports IPv4 and IPv6.
355 }
356
357 // If an interface was specified, find the ifindex.
358 uint32_t ifindex;
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700359 if (interface != OIF_NONE) {
Lorenzo Colittiba25df92014-06-18 00:22:17 +0900360 ifindex = if_nametoindex(interface);
361 if (!ifindex) {
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700362 ALOGE("cannot find interface %s", interface);
Lorenzo Colittiba25df92014-06-18 00:22:17 +0900363 return -ENODEV;
Sreeram Ramachandran7619e1b2014-04-15 14:23:08 -0700364 }
365 }
366
Lorenzo Colittiba25df92014-06-18 00:22:17 +0900367 // If a nexthop was specified, parse it as the same family as the prefix.
368 uint8_t rawNexthop[sizeof(in6_addr)];
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700369 if (nexthop && inet_pton(family, nexthop, rawNexthop) <= 0) {
370 ALOGE("inet_pton failed for nexthop %s", nexthop);
Lorenzo Colittiba25df92014-06-18 00:22:17 +0900371 return -EINVAL;
372 }
373
Lorenzo Colitti4753afd2014-06-20 23:03:29 +0900374 // Assemble a rtmsg and put it in an array of iovec structures.
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700375 rtmsg route = {
Lorenzo Colittiba25df92014-06-18 00:22:17 +0900376 .rtm_protocol = RTPROT_STATIC,
377 .rtm_type = RTN_UNICAST,
378 .rtm_family = family,
379 .rtm_dst_len = prefixLength,
380 };
Lorenzo Colitti4753afd2014-06-20 23:03:29 +0900381
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700382 rtattr rtaDst = { U16_RTA_LENGTH(rawLength), RTA_DST };
383 rtattr rtaGateway = { U16_RTA_LENGTH(rawLength), RTA_GATEWAY };
Lorenzo Colittiba25df92014-06-18 00:22:17 +0900384
385 iovec iov[] = {
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700386 { NULL, 0 },
387 { &route, sizeof(route) },
388 { &RTATTR_TABLE, sizeof(RTATTR_TABLE) },
389 { &table, sizeof(table) },
390 { &rtaDst, sizeof(rtaDst) },
391 { rawAddress, static_cast<size_t>(rawLength) },
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700392 { &RTATTR_OIF, interface != OIF_NONE ? sizeof(RTATTR_OIF) : 0 },
393 { &ifindex, interface != OIF_NONE ? sizeof(ifindex) : 0 },
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700394 { &rtaGateway, nexthop ? sizeof(rtaGateway) : 0 },
395 { rawNexthop, nexthop ? static_cast<size_t>(rawLength) : 0 },
Lorenzo Colittiba25df92014-06-18 00:22:17 +0900396 };
Lorenzo Colittiba25df92014-06-18 00:22:17 +0900397
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700398 uint16_t flags = (action == RTM_NEWROUTE) ? NETLINK_CREATE_REQUEST_FLAGS :
399 NETLINK_REQUEST_FLAGS;
Lorenzo Colitti4753afd2014-06-20 23:03:29 +0900400 return sendNetlinkRequest(action, flags, iov, ARRAY_SIZE(iov));
Sreeram Ramachandran7619e1b2014-04-15 14:23:08 -0700401}
402
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700403// Add rules to allow legacy routes added through the requestRouteToHost() API.
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700404WARN_UNUSED_RESULT int addLegacyRouteRules() {
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700405 Fwmark fwmark;
406 Fwmark mask;
407
408 fwmark.explicitlySelected = false;
409 mask.explicitlySelected = true;
410
411 // Rules to allow legacy routes to override the default network.
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -0700412 if (int ret = modifyIpRule(RTM_NEWRULE, RULE_PRIORITY_LEGACY_SYSTEM, ROUTE_TABLE_LEGACY_SYSTEM,
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700413 fwmark.intValue, mask.intValue)) {
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700414 return ret;
415 }
416 if (int ret = modifyIpRule(RTM_NEWRULE, RULE_PRIORITY_LEGACY_NETWORK,
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700417 ROUTE_TABLE_LEGACY_NETWORK, fwmark.intValue, mask.intValue)) {
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700418 return ret;
419 }
420
421 fwmark.permission = PERMISSION_SYSTEM;
422 mask.permission = PERMISSION_SYSTEM;
423
424 // A rule to allow legacy routes from system apps to override VPNs.
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -0700425 return modifyIpRule(RTM_NEWRULE, RULE_PRIORITY_VPN_OVERRIDE_SYSTEM, ROUTE_TABLE_LEGACY_SYSTEM,
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700426 fwmark.intValue, mask.intValue);
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700427}
428
429// Add a new rule to look up the 'main' table, with the same selectors as the "default network"
430// rule, but with a lower priority. Since the default network rule points to a table with a default
431// route, the rule we're adding will never be used for normal routing lookups. However, the kernel
432// may fall-through to it to find directly-connected routes when it validates that a nexthop (in a
433// route being added) is reachable.
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700434WARN_UNUSED_RESULT int addDirectlyConnectedRule() {
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700435 Fwmark fwmark;
436 Fwmark mask;
437
438 fwmark.netId = NETID_UNSET;
439 mask.netId = FWMARK_NET_ID_MASK;
440
441 return modifyIpRule(RTM_NEWRULE, RULE_PRIORITY_DIRECTLY_CONNECTED, RT_TABLE_MAIN,
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700442 fwmark.intValue, mask.intValue, IIF_NONE, OIF_NONE, UID_ROOT, UID_ROOT);
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700443}
444
445// Add a rule to preempt the pre-defined "from all lookup main" rule. Packets that reach this rule
446// will be null-routed, and won't fall-through to the main table.
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700447WARN_UNUSED_RESULT int addUnreachableRule() {
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700448 return modifyIpRule(RTM_NEWRULE, RULE_PRIORITY_UNREACHABLE, RT_TABLE_UNSPEC, MARK_UNSET,
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700449 MARK_UNSET);
450}
451
452// A rule to lookup the local network before looking up the default network.
453WARN_UNUSED_RESULT int addImplicitLocalNetworkRule() {
454 Fwmark fwmark;
455 Fwmark mask;
456
457 fwmark.explicitlySelected = false;
458 mask.explicitlySelected = true;
459
460 return modifyIpRule(RTM_NEWRULE, RULE_PRIORITY_LOCAL_NETWORK, ROUTE_TABLE_LOCAL_NETWORK,
461 fwmark.intValue, mask.intValue);
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700462}
463
464// An iptables rule to mark incoming packets on a network with the netId of the network.
465//
466// This is so that the kernel can:
467// + Use the right fwmark for (and thus correctly route) replies (e.g.: TCP RST, ICMP errors, ping
468// replies, SYN-ACKs, etc).
469// + Mark sockets that accept connections from this interface so that the connection stays on the
470// same interface.
471WARN_UNUSED_RESULT int modifyIncomingPacketMark(unsigned netId, const char* interface,
472 Permission permission, bool add) {
473 Fwmark fwmark;
474
475 fwmark.netId = netId;
476 fwmark.explicitlySelected = true;
477 fwmark.protectedFromVpn = true;
478 fwmark.permission = permission;
479
Sreeram Ramachandranb1425cc2014-06-23 18:54:27 -0700480 char markString[UINT32_HEX_STRLEN];
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700481 snprintf(markString, sizeof(markString), "0x%x", fwmark.intValue);
482
Sreeram Ramachandranb1425cc2014-06-23 18:54:27 -0700483 if (execIptables(V4V6, "-t", "mangle", add ? "-A" : "-D", "INPUT", "-i", interface, "-j",
484 "MARK", "--set-mark", markString, NULL)) {
485 ALOGE("failed to change iptables rule that sets incoming packet mark");
486 return -EREMOTEIO;
487 }
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700488
Sreeram Ramachandranb1425cc2014-06-23 18:54:27 -0700489 return 0;
490}
491
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700492// A rule to route traffic based on an explicitly chosen network.
493//
494// Supports apps that use the multinetwork APIs to restrict their traffic to a network.
495//
496// Even though we check permissions at the time we set a netId into the fwmark of a socket, we need
497// to check it again in the rules here, because a network's permissions may have been updated via
498// modifyNetworkPermission().
499WARN_UNUSED_RESULT int modifyExplicitNetworkRule(unsigned netId, uint32_t table,
500 Permission permission, uid_t uidStart,
501 uid_t uidEnd, bool add) {
Sreeram Ramachandraneb27b7e2014-07-01 14:30:30 -0700502 Fwmark fwmark;
503 Fwmark mask;
504
505 fwmark.netId = netId;
506 mask.netId = FWMARK_NET_ID_MASK;
507
Sreeram Ramachandran122f5812014-05-11 20:29:49 -0700508 fwmark.explicitlySelected = true;
509 mask.explicitlySelected = true;
Sreeram Ramachandran5c181bf2014-04-07 14:10:04 -0700510
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700511 fwmark.permission = permission;
512 mask.permission = permission;
Sreeram Ramachandraneb27b7e2014-07-01 14:30:30 -0700513
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700514 return modifyIpRule(add ? RTM_NEWRULE : RTM_DELRULE, RULE_PRIORITY_EXPLICIT_NETWORK, table,
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700515 fwmark.intValue, mask.intValue, IIF_NONE, OIF_NONE, uidStart, uidEnd);
Sreeram Ramachandran5c181bf2014-04-07 14:10:04 -0700516}
517
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700518// A rule to route traffic based on a chosen outgoing interface.
519//
520// Supports apps that use SO_BINDTODEVICE or IP_PKTINFO options and the kernel that already knows
521// the outgoing interface (typically for link-local communications).
522WARN_UNUSED_RESULT int modifyOutputInterfaceRule(const char* interface, uint32_t table,
523 Permission permission, uid_t uidStart,
524 uid_t uidEnd, bool add) {
525 Fwmark fwmark;
526 Fwmark mask;
Sreeram Ramachandran4043f012014-06-23 12:41:37 -0700527
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700528 fwmark.permission = permission;
529 mask.permission = permission;
Sreeram Ramachandranb1425cc2014-06-23 18:54:27 -0700530
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700531 return modifyIpRule(add ? RTM_NEWRULE : RTM_DELRULE, RULE_PRIORITY_OUTPUT_INTERFACE, table,
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700532 fwmark.intValue, mask.intValue, IIF_NONE, interface, uidStart, uidEnd);
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700533}
534
535// A rule to route traffic based on the chosen network.
536//
537// This is for sockets that have not explicitly requested a particular network, but have been
538// bound to one when they called connect(). This ensures that sockets connected on a particular
539// network stay on that network even if the default network changes.
540WARN_UNUSED_RESULT int modifyImplicitNetworkRule(unsigned netId, uint32_t table,
541 Permission permission, bool add) {
542 Fwmark fwmark;
543 Fwmark mask;
544
545 fwmark.netId = netId;
546 mask.netId = FWMARK_NET_ID_MASK;
547
548 fwmark.explicitlySelected = false;
549 mask.explicitlySelected = true;
550
551 fwmark.permission = permission;
552 mask.permission = permission;
553
554 return modifyIpRule(add ? RTM_NEWRULE : RTM_DELRULE, RULE_PRIORITY_IMPLICIT_NETWORK, table,
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700555 fwmark.intValue, mask.intValue);
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700556}
557
558// A rule to route all traffic from a given set of UIDs to go over the VPN.
559//
560// Notice that this rule doesn't use the netId. I.e., no matter what netId the user's socket may
561// have, if they are subject to this VPN, their traffic has to go through it. Allows the traffic to
562// bypass the VPN if the protectedFromVpn bit is set.
563WARN_UNUSED_RESULT int modifyVpnUidRangeRule(uint32_t table, uid_t uidStart, uid_t uidEnd,
564 bool add) {
Sreeram Ramachandran4043f012014-06-23 12:41:37 -0700565 Fwmark fwmark;
566 Fwmark mask;
567
Sreeram Ramachandran4043f012014-06-23 12:41:37 -0700568 fwmark.protectedFromVpn = false;
569 mask.protectedFromVpn = true;
Sreeram Ramachandranb1425cc2014-06-23 18:54:27 -0700570
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700571 return modifyIpRule(add ? RTM_NEWRULE : RTM_DELRULE, RULE_PRIORITY_SECURE_VPN, table,
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700572 fwmark.intValue, mask.intValue, IIF_NONE, OIF_NONE, uidStart, uidEnd);
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700573}
574
575// A rule to allow system apps to send traffic over this VPN even if they are not part of the target
576// set of UIDs.
577//
578// This is needed for DnsProxyListener to correctly resolve a request for a user who is in the
579// target set, but where the DnsProxyListener itself is not.
580WARN_UNUSED_RESULT int modifyVpnSystemPermissionRule(unsigned netId, uint32_t table, bool add) {
581 Fwmark fwmark;
582 Fwmark mask;
583
584 fwmark.netId = netId;
585 mask.netId = FWMARK_NET_ID_MASK;
586
587 fwmark.permission = PERMISSION_SYSTEM;
588 mask.permission = PERMISSION_SYSTEM;
589
590 return modifyIpRule(add ? RTM_NEWRULE : RTM_DELRULE, RULE_PRIORITY_SECURE_VPN, table,
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700591 fwmark.intValue, mask.intValue);
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700592}
593
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700594WARN_UNUSED_RESULT int modifyTetheringRule(uint16_t action, const char* inputInterface,
595 const char* outputInterface) {
596 uint32_t table = getRouteTableForInterface(outputInterface);
Sreeram Ramachandran6a773532014-07-11 09:10:20 -0700597 if (table == RT_TABLE_UNSPEC) {
598 return -ESRCH;
599 }
600
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700601 return modifyIpRule(action, RULE_PRIORITY_TETHERING, table, MARK_UNSET, MARK_UNSET,
602 inputInterface, outputInterface, INVALID_UID, INVALID_UID);
603}
604
605WARN_UNUSED_RESULT int modifyLocalNetwork(unsigned netId, const char* interface, bool add) {
Sreeram Ramachandran6a773532014-07-11 09:10:20 -0700606 if (int ret = modifyIncomingPacketMark(netId, interface, PERMISSION_NONE, add)) {
607 return ret;
608 }
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700609 return modifyOutputInterfaceRule(interface, ROUTE_TABLE_LOCAL_NETWORK, PERMISSION_NONE,
610 INVALID_UID, INVALID_UID, add);
Sreeram Ramachandran6a773532014-07-11 09:10:20 -0700611}
612
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700613WARN_UNUSED_RESULT int modifyPhysicalNetwork(unsigned netId, const char* interface,
614 Permission permission, bool add) {
615 uint32_t table = getRouteTableForInterface(interface);
616 if (table == RT_TABLE_UNSPEC) {
617 return -ESRCH;
618 }
619
620 if (int ret = modifyIncomingPacketMark(netId, interface, permission, add)) {
621 return ret;
622 }
623 if (int ret = modifyExplicitNetworkRule(netId, table, permission, INVALID_UID, INVALID_UID,
624 add)) {
625 return ret;
626 }
627 if (int ret = modifyOutputInterfaceRule(interface, table, permission, INVALID_UID, INVALID_UID,
628 add)) {
629 return ret;
630 }
631 return modifyImplicitNetworkRule(netId, table, permission, add);
632}
633
634WARN_UNUSED_RESULT int modifyVirtualNetwork(unsigned netId, const char* interface,
635 const UidRanges& uidRanges, bool add,
636 bool modifyNonUidBasedRules) {
637 uint32_t table = getRouteTableForInterface(interface);
638 if (table == RT_TABLE_UNSPEC) {
639 return -ESRCH;
640 }
641
Sreeram Ramachandrane09b20a2014-07-05 17:15:14 -0700642 for (const UidRanges::Range& range : uidRanges.getRanges()) {
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700643 if (int ret = modifyExplicitNetworkRule(netId, table, PERMISSION_NONE, range.first,
644 range.second, add)) {
Sreeram Ramachandranb1425cc2014-06-23 18:54:27 -0700645 return ret;
646 }
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700647 if (int ret = modifyOutputInterfaceRule(interface, table, PERMISSION_NONE, range.first,
648 range.second, add)) {
649 return ret;
650 }
651 if (int ret = modifyVpnUidRangeRule(table, range.first, range.second, add)) {
Sreeram Ramachandranb1425cc2014-06-23 18:54:27 -0700652 return ret;
653 }
Sreeram Ramachandran4043f012014-06-23 12:41:37 -0700654 }
655
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700656 if (modifyNonUidBasedRules) {
657 if (int ret = modifyIncomingPacketMark(netId, interface, PERMISSION_NONE, add)) {
Sreeram Ramachandraneb27b7e2014-07-01 14:30:30 -0700658 return ret;
659 }
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700660 if (int ret = modifyExplicitNetworkRule(netId, table, PERMISSION_NONE, UID_ROOT, UID_ROOT,
661 add)) {
Sreeram Ramachandranb1425cc2014-06-23 18:54:27 -0700662 return ret;
663 }
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700664 return modifyVpnSystemPermissionRule(netId, table, add);
Sreeram Ramachandranb1425cc2014-06-23 18:54:27 -0700665 }
666
667 return 0;
Sreeram Ramachandran4043f012014-06-23 12:41:37 -0700668}
669
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700670WARN_UNUSED_RESULT int modifyDefaultNetwork(uint16_t action, const char* interface,
671 Permission permission) {
Sreeram Ramachandran9c0d3132014-04-10 20:35:04 -0700672 uint32_t table = getRouteTableForInterface(interface);
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700673 if (table == RT_TABLE_UNSPEC) {
Lorenzo Colitti96f261e2014-06-23 15:09:54 +0900674 return -ESRCH;
Sreeram Ramachandran9c0d3132014-04-10 20:35:04 -0700675 }
676
Sreeram Ramachandran122f5812014-05-11 20:29:49 -0700677 Fwmark fwmark;
Sreeram Ramachandran122f5812014-05-11 20:29:49 -0700678 Fwmark mask;
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700679
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700680 fwmark.netId = NETID_UNSET;
Sreeram Ramachandran122f5812014-05-11 20:29:49 -0700681 mask.netId = FWMARK_NET_ID_MASK;
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700682
683 fwmark.permission = permission;
Sreeram Ramachandran122f5812014-05-11 20:29:49 -0700684 mask.permission = permission;
685
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700686 return modifyIpRule(action, RULE_PRIORITY_DEFAULT_NETWORK, table, fwmark.intValue,
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700687 mask.intValue);
Sreeram Ramachandran7619e1b2014-04-15 14:23:08 -0700688}
689
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700690// Adds or removes an IPv4 or IPv6 route to the specified table and, if it's a directly-connected
Lorenzo Colittif7fc8ec2014-06-18 00:41:58 +0900691// route, to the main table as well.
692// Returns 0 on success or negative errno on failure.
Sreeram Ramachandraneb27b7e2014-07-01 14:30:30 -0700693WARN_UNUSED_RESULT int modifyRoute(uint16_t action, const char* interface, const char* destination,
694 const char* nexthop, RouteController::TableType tableType) {
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700695 uint32_t table;
Sreeram Ramachandran38b7af12014-05-22 14:21:49 -0700696 switch (tableType) {
697 case RouteController::INTERFACE: {
698 table = getRouteTableForInterface(interface);
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700699 if (table == RT_TABLE_UNSPEC) {
700 return -ESRCH;
701 }
Sreeram Ramachandran38b7af12014-05-22 14:21:49 -0700702 break;
703 }
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700704 case RouteController::LOCAL_NETWORK: {
705 table = ROUTE_TABLE_LOCAL_NETWORK;
706 break;
707 }
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700708 case RouteController::LEGACY_NETWORK: {
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -0700709 table = ROUTE_TABLE_LEGACY_NETWORK;
Sreeram Ramachandran38b7af12014-05-22 14:21:49 -0700710 break;
711 }
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700712 case RouteController::LEGACY_SYSTEM: {
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -0700713 table = ROUTE_TABLE_LEGACY_SYSTEM;
Sreeram Ramachandran38b7af12014-05-22 14:21:49 -0700714 break;
715 }
716 }
Sreeram Ramachandran9c0d3132014-04-10 20:35:04 -0700717
Lorenzo Colittif7fc8ec2014-06-18 00:41:58 +0900718 int ret = modifyIpRoute(action, table, interface, destination, nexthop);
Sreeram Ramachandran1077d292014-06-27 06:42:11 -0700719 // We allow apps to call requestRouteToHost() multiple times with the same route, so ignore
720 // EEXIST failures when adding routes to legacy tables.
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700721 if (ret && !(action == RTM_NEWROUTE && ret == -EEXIST &&
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700722 (tableType == RouteController::LEGACY_NETWORK ||
723 tableType == RouteController::LEGACY_SYSTEM))) {
Lorenzo Colittif7fc8ec2014-06-18 00:41:58 +0900724 return ret;
Sreeram Ramachandranc9213372014-04-16 12:32:18 -0700725 }
726
727 // If there's no nexthop, this is a directly connected route. Add it to the main table also, to
Lorenzo Colittif7fc8ec2014-06-18 00:41:58 +0900728 // let the kernel find it when validating nexthops when global routes are added.
729 if (!nexthop) {
730 ret = modifyIpRoute(action, RT_TABLE_MAIN, interface, destination, NULL);
731 // A failure with action == ADD && errno == EEXIST means that the route already exists in
732 // the main table, perhaps because the kernel added it automatically as part of adding the
733 // IP address to the interface. Ignore this, but complain about everything else.
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700734 if (ret && !(action == RTM_NEWROUTE && ret == -EEXIST)) {
Lorenzo Colittif7fc8ec2014-06-18 00:41:58 +0900735 return ret;
736 }
Sreeram Ramachandranc9213372014-04-16 12:32:18 -0700737 }
738
Lorenzo Colittif7fc8ec2014-06-18 00:41:58 +0900739 return 0;
Sreeram Ramachandran9c0d3132014-04-10 20:35:04 -0700740}
741
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700742// Returns 0 on success or negative errno on failure.
743WARN_UNUSED_RESULT int flushRoutes(const char* interface) {
Sreeram Ramachandran92b66c42014-04-15 14:28:55 -0700744 uint32_t table = getRouteTableForInterface(interface);
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700745 if (table == RT_TABLE_UNSPEC) {
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700746 return -ESRCH;
Sreeram Ramachandran92b66c42014-04-15 14:28:55 -0700747 }
748
Lorenzo Colitti357e5622014-06-17 16:14:17 +0900749 char tableString[UINT32_STRLEN];
750 snprintf(tableString, sizeof(tableString), "%u", table);
751
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700752 for (size_t i = 0; i < ARRAY_SIZE(IP_VERSIONS); ++i) {
Lorenzo Colitti357e5622014-06-17 16:14:17 +0900753 const char* argv[] = {
754 IP_PATH,
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700755 IP_VERSIONS[i],
Sreeram Ramachandran72999d62014-07-02 18:06:34 -0700756 "route",
Lorenzo Colitti357e5622014-06-17 16:14:17 +0900757 "flush",
758 "table",
759 tableString,
760 };
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700761 if (android_fork_execvp(ARRAY_SIZE(argv), const_cast<char**>(argv), NULL, false, false)) {
762 ALOGE("failed to flush routes");
763 return -EREMOTEIO;
Lorenzo Colitti357e5622014-06-17 16:14:17 +0900764 }
765 }
766
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -0700767 interfaceToTable.erase(interface);
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700768 return 0;
Sreeram Ramachandran92b66c42014-04-15 14:28:55 -0700769}
770
Sreeram Ramachandran5c181bf2014-04-07 14:10:04 -0700771} // namespace
772
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700773int RouteController::Init(unsigned localNetId) {
774 if (int ret = addDirectlyConnectedRule()) {
Sreeram Ramachandraneb27b7e2014-07-01 14:30:30 -0700775 return ret;
776 }
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700777 if (int ret = addLegacyRouteRules()) {
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700778 return ret;
779 }
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700780 // TODO: Enable once we are sure everything works.
781 if (false) {
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700782 if (int ret = addUnreachableRule()) {
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -0700783 return ret;
784 }
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700785 }
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700786 if (int ret = addImplicitLocalNetworkRule()) {
787 return ret;
788 }
789 // Add a rule to lookup the local network it has been explicitly selected.
790 if (int ret = modifyExplicitNetworkRule(localNetId, ROUTE_TABLE_LOCAL_NETWORK, PERMISSION_NONE,
791 INVALID_UID, INVALID_UID, ACTION_ADD)) {
792 return ret;
793 }
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -0700794 updateTableNamesFile();
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700795 return 0;
Sreeram Ramachandran8fe9c8e2014-04-16 12:08:05 -0700796}
797
Sreeram Ramachandran6a773532014-07-11 09:10:20 -0700798int RouteController::addInterfaceToLocalNetwork(unsigned netId, const char* interface) {
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700799 return modifyLocalNetwork(netId, interface, ACTION_ADD);
Sreeram Ramachandran6a773532014-07-11 09:10:20 -0700800}
801
802int RouteController::removeInterfaceFromLocalNetwork(unsigned netId, const char* interface) {
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700803 return modifyLocalNetwork(netId, interface, ACTION_DEL);
Sreeram Ramachandran6a773532014-07-11 09:10:20 -0700804}
805
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700806int RouteController::addInterfaceToPhysicalNetwork(unsigned netId, const char* interface,
807 Permission permission) {
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -0700808 if (int ret = modifyPhysicalNetwork(netId, interface, permission, ACTION_ADD)) {
809 return ret;
810 }
811 updateTableNamesFile();
812 return 0;
Sreeram Ramachandran5c181bf2014-04-07 14:10:04 -0700813}
814
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700815int RouteController::removeInterfaceFromPhysicalNetwork(unsigned netId, const char* interface,
816 Permission permission) {
817 if (int ret = modifyPhysicalNetwork(netId, interface, permission, ACTION_DEL)) {
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700818 return ret;
819 }
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -0700820 if (int ret = flushRoutes(interface)) {
821 return ret;
822 }
823 updateTableNamesFile();
824 return 0;
Sreeram Ramachandran379bd332014-04-10 19:58:06 -0700825}
826
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700827int RouteController::addInterfaceToVirtualNetwork(unsigned netId, const char* interface,
828 const UidRanges& uidRanges) {
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -0700829 if (int ret = modifyVirtualNetwork(netId, interface, uidRanges, ACTION_ADD,
830 MODIFY_NON_UID_BASED_RULES)) {
831 return ret;
832 }
833 updateTableNamesFile();
834 return 0;
Sreeram Ramachandran4043f012014-06-23 12:41:37 -0700835}
836
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700837int RouteController::removeInterfaceFromVirtualNetwork(unsigned netId, const char* interface,
838 const UidRanges& uidRanges) {
839 if (int ret = modifyVirtualNetwork(netId, interface, uidRanges, ACTION_DEL,
840 MODIFY_NON_UID_BASED_RULES)) {
Sreeram Ramachandran4043f012014-06-23 12:41:37 -0700841 return ret;
842 }
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -0700843 if (int ret = flushRoutes(interface)) {
844 return ret;
845 }
846 updateTableNamesFile();
847 return 0;
Sreeram Ramachandran4043f012014-06-23 12:41:37 -0700848}
849
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700850int RouteController::modifyPhysicalNetworkPermission(unsigned netId, const char* interface,
851 Permission oldPermission,
852 Permission newPermission) {
Sreeram Ramachandran379bd332014-04-10 19:58:06 -0700853 // Add the new rules before deleting the old ones, to avoid race conditions.
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700854 if (int ret = modifyPhysicalNetwork(netId, interface, newPermission, ACTION_ADD)) {
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700855 return ret;
856 }
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700857 return modifyPhysicalNetwork(netId, interface, oldPermission, ACTION_DEL);
Sreeram Ramachandranb1425cc2014-06-23 18:54:27 -0700858}
859
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700860int RouteController::addUsersToVirtualNetwork(unsigned netId, const char* interface,
861 const UidRanges& uidRanges) {
862 return modifyVirtualNetwork(netId, interface, uidRanges, ACTION_ADD,
863 !MODIFY_NON_UID_BASED_RULES);
Sreeram Ramachandranb1425cc2014-06-23 18:54:27 -0700864}
865
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700866int RouteController::removeUsersFromVirtualNetwork(unsigned netId, const char* interface,
867 const UidRanges& uidRanges) {
868 return modifyVirtualNetwork(netId, interface, uidRanges, ACTION_DEL,
869 !MODIFY_NON_UID_BASED_RULES);
Sreeram Ramachandran9c0d3132014-04-10 20:35:04 -0700870}
871
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700872int RouteController::addInterfaceToDefaultNetwork(const char* interface, Permission permission) {
873 return modifyDefaultNetwork(RTM_NEWRULE, interface, permission);
Sreeram Ramachandran9c0d3132014-04-10 20:35:04 -0700874}
875
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700876int RouteController::removeInterfaceFromDefaultNetwork(const char* interface,
877 Permission permission) {
878 return modifyDefaultNetwork(RTM_DELRULE, interface, permission);
Sreeram Ramachandran5c181bf2014-04-07 14:10:04 -0700879}
Sreeram Ramachandran7619e1b2014-04-15 14:23:08 -0700880
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700881int RouteController::addRoute(const char* interface, const char* destination, const char* nexthop,
Sreeram Ramachandraneb27b7e2014-07-01 14:30:30 -0700882 TableType tableType) {
883 return modifyRoute(RTM_NEWROUTE, interface, destination, nexthop, tableType);
Sreeram Ramachandran7619e1b2014-04-15 14:23:08 -0700884}
885
Lorenzo Colittif7fc8ec2014-06-18 00:41:58 +0900886int RouteController::removeRoute(const char* interface, const char* destination,
Sreeram Ramachandraneb27b7e2014-07-01 14:30:30 -0700887 const char* nexthop, TableType tableType) {
888 return modifyRoute(RTM_DELROUTE, interface, destination, nexthop, tableType);
Sreeram Ramachandran7619e1b2014-04-15 14:23:08 -0700889}
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700890
891int RouteController::enableTethering(const char* inputInterface, const char* outputInterface) {
892 return modifyTetheringRule(RTM_NEWRULE, inputInterface, outputInterface);
893}
894
895int RouteController::disableTethering(const char* inputInterface, const char* outputInterface) {
896 return modifyTetheringRule(RTM_DELRULE, inputInterface, outputInterface);
897}