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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;
Sreeram Ramachandran111bec22014-07-22 18:51:06 -070039const uint32_t RULE_PRIORITY_VPN_OUTPUT_TO_LOCAL = 11000;
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -070040const 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;
Sreeram Ramachandran95684ba2014-07-23 13:27:31 -070048const uint32_t RULE_PRIORITY_BYPASSABLE_VPN = 20000;
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -070049// 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// An iptables rule to mark incoming packets on a network with the netId of the network.
404//
405// This is so that the kernel can:
406// + Use the right fwmark for (and thus correctly route) replies (e.g.: TCP RST, ICMP errors, ping
407// replies, SYN-ACKs, etc).
408// + Mark sockets that accept connections from this interface so that the connection stays on the
409// same interface.
410WARN_UNUSED_RESULT int modifyIncomingPacketMark(unsigned netId, const char* interface,
411 Permission permission, bool add) {
412 Fwmark fwmark;
413
414 fwmark.netId = netId;
415 fwmark.explicitlySelected = true;
416 fwmark.protectedFromVpn = true;
417 fwmark.permission = permission;
418
Sreeram Ramachandranb1425cc2014-06-23 18:54:27 -0700419 char markString[UINT32_HEX_STRLEN];
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700420 snprintf(markString, sizeof(markString), "0x%x", fwmark.intValue);
421
Sreeram Ramachandranb1425cc2014-06-23 18:54:27 -0700422 if (execIptables(V4V6, "-t", "mangle", add ? "-A" : "-D", "INPUT", "-i", interface, "-j",
423 "MARK", "--set-mark", markString, NULL)) {
424 ALOGE("failed to change iptables rule that sets incoming packet mark");
425 return -EREMOTEIO;
426 }
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700427
Sreeram Ramachandranb1425cc2014-06-23 18:54:27 -0700428 return 0;
429}
430
Sreeram Ramachandran111bec22014-07-22 18:51:06 -0700431// A rule to route responses to the local network forwarded via the VPN.
432//
433// When a VPN is in effect, packets from the local network to upstream networks are forwarded into
434// the VPN's tunnel interface. When the VPN forwards the responses, they emerge out of the tunnel.
435WARN_UNUSED_RESULT int modifyVpnOutputToLocalRule(const char* vpnInterface, bool add) {
436 return modifyIpRule(add ? RTM_NEWRULE : RTM_DELRULE, RULE_PRIORITY_VPN_OUTPUT_TO_LOCAL,
437 ROUTE_TABLE_LOCAL_NETWORK, MARK_UNSET, MARK_UNSET, vpnInterface, OIF_NONE,
438 INVALID_UID, INVALID_UID);
439}
440
Sreeram Ramachandranfa9f4dc2014-07-22 18:16:44 -0700441// A rule to route all traffic from a given set of UIDs to go over the VPN.
442//
443// Notice that this rule doesn't use the netId. I.e., no matter what netId the user's socket may
444// have, if they are subject to this VPN, their traffic has to go through it. Allows the traffic to
445// bypass the VPN if the protectedFromVpn bit is set.
446WARN_UNUSED_RESULT int modifyVpnUidRangeRule(uint32_t table, uid_t uidStart, uid_t uidEnd,
Sreeram Ramachandran95684ba2014-07-23 13:27:31 -0700447 bool secure, bool add) {
Sreeram Ramachandranfa9f4dc2014-07-22 18:16:44 -0700448 Fwmark fwmark;
449 Fwmark mask;
450
451 fwmark.protectedFromVpn = false;
452 mask.protectedFromVpn = true;
453
Sreeram Ramachandran95684ba2014-07-23 13:27:31 -0700454 uint32_t priority;
455
456 if (secure) {
457 priority = RULE_PRIORITY_SECURE_VPN;
458 } else {
459 priority = RULE_PRIORITY_BYPASSABLE_VPN;
460
461 fwmark.explicitlySelected = false;
462 mask.explicitlySelected = true;
463 }
464
465 return modifyIpRule(add ? RTM_NEWRULE : RTM_DELRULE, priority, table, fwmark.intValue,
466 mask.intValue, IIF_NONE, OIF_NONE, uidStart, uidEnd);
Sreeram Ramachandranfa9f4dc2014-07-22 18:16:44 -0700467}
468
469// A rule to allow system apps to send traffic over this VPN even if they are not part of the target
470// set of UIDs.
471//
472// This is needed for DnsProxyListener to correctly resolve a request for a user who is in the
473// target set, but where the DnsProxyListener itself is not.
Sreeram Ramachandran95684ba2014-07-23 13:27:31 -0700474WARN_UNUSED_RESULT int modifyVpnSystemPermissionRule(unsigned netId, uint32_t table, bool secure,
475 bool add) {
Sreeram Ramachandranfa9f4dc2014-07-22 18:16:44 -0700476 Fwmark fwmark;
477 Fwmark mask;
478
479 fwmark.netId = netId;
480 mask.netId = FWMARK_NET_ID_MASK;
481
482 fwmark.permission = PERMISSION_SYSTEM;
483 mask.permission = PERMISSION_SYSTEM;
484
Sreeram Ramachandran95684ba2014-07-23 13:27:31 -0700485 uint32_t priority = secure ? RULE_PRIORITY_SECURE_VPN : RULE_PRIORITY_BYPASSABLE_VPN;
486
487 return modifyIpRule(add ? RTM_NEWRULE : RTM_DELRULE, priority, table, fwmark.intValue,
488 mask.intValue);
Sreeram Ramachandranfa9f4dc2014-07-22 18:16:44 -0700489}
490
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700491// A rule to route traffic based on an explicitly chosen network.
492//
493// Supports apps that use the multinetwork APIs to restrict their traffic to a network.
494//
495// Even though we check permissions at the time we set a netId into the fwmark of a socket, we need
496// to check it again in the rules here, because a network's permissions may have been updated via
497// modifyNetworkPermission().
498WARN_UNUSED_RESULT int modifyExplicitNetworkRule(unsigned netId, uint32_t table,
499 Permission permission, uid_t uidStart,
500 uid_t uidEnd, bool add) {
Sreeram Ramachandraneb27b7e2014-07-01 14:30:30 -0700501 Fwmark fwmark;
502 Fwmark mask;
503
504 fwmark.netId = netId;
505 mask.netId = FWMARK_NET_ID_MASK;
506
Sreeram Ramachandran122f5812014-05-11 20:29:49 -0700507 fwmark.explicitlySelected = true;
508 mask.explicitlySelected = true;
Sreeram Ramachandran5c181bf2014-04-07 14:10:04 -0700509
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700510 fwmark.permission = permission;
511 mask.permission = permission;
Sreeram Ramachandraneb27b7e2014-07-01 14:30:30 -0700512
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700513 return modifyIpRule(add ? RTM_NEWRULE : RTM_DELRULE, RULE_PRIORITY_EXPLICIT_NETWORK, table,
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700514 fwmark.intValue, mask.intValue, IIF_NONE, OIF_NONE, uidStart, uidEnd);
Sreeram Ramachandran5c181bf2014-04-07 14:10:04 -0700515}
516
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700517// A rule to route traffic based on a chosen outgoing interface.
518//
519// Supports apps that use SO_BINDTODEVICE or IP_PKTINFO options and the kernel that already knows
520// the outgoing interface (typically for link-local communications).
521WARN_UNUSED_RESULT int modifyOutputInterfaceRule(const char* interface, uint32_t table,
522 Permission permission, uid_t uidStart,
523 uid_t uidEnd, bool add) {
524 Fwmark fwmark;
525 Fwmark mask;
Sreeram Ramachandran4043f012014-06-23 12:41:37 -0700526
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700527 fwmark.permission = permission;
528 mask.permission = permission;
Sreeram Ramachandranb1425cc2014-06-23 18:54:27 -0700529
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700530 return modifyIpRule(add ? RTM_NEWRULE : RTM_DELRULE, RULE_PRIORITY_OUTPUT_INTERFACE, table,
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700531 fwmark.intValue, mask.intValue, IIF_NONE, interface, uidStart, uidEnd);
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700532}
533
534// A rule to route traffic based on the chosen network.
535//
536// This is for sockets that have not explicitly requested a particular network, but have been
537// bound to one when they called connect(). This ensures that sockets connected on a particular
538// network stay on that network even if the default network changes.
539WARN_UNUSED_RESULT int modifyImplicitNetworkRule(unsigned netId, uint32_t table,
540 Permission permission, bool add) {
541 Fwmark fwmark;
542 Fwmark mask;
543
544 fwmark.netId = netId;
545 mask.netId = FWMARK_NET_ID_MASK;
546
547 fwmark.explicitlySelected = false;
548 mask.explicitlySelected = true;
549
550 fwmark.permission = permission;
551 mask.permission = permission;
552
553 return modifyIpRule(add ? RTM_NEWRULE : RTM_DELRULE, RULE_PRIORITY_IMPLICIT_NETWORK, table,
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700554 fwmark.intValue, mask.intValue);
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700555}
556
Sreeram Ramachandranfa9f4dc2014-07-22 18:16:44 -0700557// Add rules to allow legacy routes added through the requestRouteToHost() API.
558WARN_UNUSED_RESULT int addLegacyRouteRules() {
Sreeram Ramachandran4043f012014-06-23 12:41:37 -0700559 Fwmark fwmark;
560 Fwmark mask;
561
Sreeram Ramachandranfa9f4dc2014-07-22 18:16:44 -0700562 fwmark.explicitlySelected = false;
563 mask.explicitlySelected = true;
Sreeram Ramachandranb1425cc2014-06-23 18:54:27 -0700564
Sreeram Ramachandranfa9f4dc2014-07-22 18:16:44 -0700565 // Rules to allow legacy routes to override the default network.
566 if (int ret = modifyIpRule(RTM_NEWRULE, RULE_PRIORITY_LEGACY_SYSTEM, ROUTE_TABLE_LEGACY_SYSTEM,
567 fwmark.intValue, mask.intValue)) {
568 return ret;
569 }
570 if (int ret = modifyIpRule(RTM_NEWRULE, RULE_PRIORITY_LEGACY_NETWORK,
571 ROUTE_TABLE_LEGACY_NETWORK, fwmark.intValue, mask.intValue)) {
572 return ret;
573 }
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700574
575 fwmark.permission = PERMISSION_SYSTEM;
576 mask.permission = PERMISSION_SYSTEM;
577
Sreeram Ramachandranfa9f4dc2014-07-22 18:16:44 -0700578 // A rule to allow legacy routes from system apps to override VPNs.
579 return modifyIpRule(RTM_NEWRULE, RULE_PRIORITY_VPN_OVERRIDE_SYSTEM, ROUTE_TABLE_LEGACY_SYSTEM,
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700580 fwmark.intValue, mask.intValue);
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700581}
582
Sreeram Ramachandranfa9f4dc2014-07-22 18:16:44 -0700583// Add rules to lookup the local network when specified explicitly or otherwise.
584WARN_UNUSED_RESULT int addLocalNetworkRules(unsigned localNetId) {
585 if (int ret = modifyExplicitNetworkRule(localNetId, ROUTE_TABLE_LOCAL_NETWORK, PERMISSION_NONE,
586 INVALID_UID, INVALID_UID, ACTION_ADD)) {
587 return ret;
Sreeram Ramachandran6a773532014-07-11 09:10:20 -0700588 }
589
Sreeram Ramachandranfa9f4dc2014-07-22 18:16:44 -0700590 Fwmark fwmark;
591 Fwmark mask;
592
593 fwmark.explicitlySelected = false;
594 mask.explicitlySelected = true;
595
596 return modifyIpRule(RTM_NEWRULE, RULE_PRIORITY_LOCAL_NETWORK, ROUTE_TABLE_LOCAL_NETWORK,
597 fwmark.intValue, mask.intValue);
598}
599
600// Add a new rule to look up the 'main' table, with the same selectors as the "default network"
601// rule, but with a lower priority. Since the default network rule points to a table with a default
602// route, the rule we're adding will never be used for normal routing lookups. However, the kernel
603// may fall-through to it to find directly-connected routes when it validates that a nexthop (in a
604// route being added) is reachable.
605WARN_UNUSED_RESULT int addDirectlyConnectedRule() {
606 Fwmark fwmark;
607 Fwmark mask;
608
609 fwmark.netId = NETID_UNSET;
610 mask.netId = FWMARK_NET_ID_MASK;
611
612 return modifyIpRule(RTM_NEWRULE, RULE_PRIORITY_DIRECTLY_CONNECTED, RT_TABLE_MAIN,
613 fwmark.intValue, mask.intValue, IIF_NONE, OIF_NONE, UID_ROOT, UID_ROOT);
614}
615
616// Add a rule to preempt the pre-defined "from all lookup main" rule. Packets that reach this rule
617// will be null-routed, and won't fall-through to the main table.
618WARN_UNUSED_RESULT int addUnreachableRule() {
619 return modifyIpRule(RTM_NEWRULE, RULE_PRIORITY_UNREACHABLE, RT_TABLE_UNSPEC, MARK_UNSET,
620 MARK_UNSET);
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700621}
622
623WARN_UNUSED_RESULT int modifyLocalNetwork(unsigned netId, const char* interface, bool add) {
Sreeram Ramachandran6a773532014-07-11 09:10:20 -0700624 if (int ret = modifyIncomingPacketMark(netId, interface, PERMISSION_NONE, add)) {
625 return ret;
626 }
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700627 return modifyOutputInterfaceRule(interface, ROUTE_TABLE_LOCAL_NETWORK, PERMISSION_NONE,
628 INVALID_UID, INVALID_UID, add);
Sreeram Ramachandran6a773532014-07-11 09:10:20 -0700629}
630
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700631WARN_UNUSED_RESULT int modifyPhysicalNetwork(unsigned netId, const char* interface,
632 Permission permission, bool add) {
633 uint32_t table = getRouteTableForInterface(interface);
634 if (table == RT_TABLE_UNSPEC) {
635 return -ESRCH;
636 }
637
638 if (int ret = modifyIncomingPacketMark(netId, interface, permission, add)) {
639 return ret;
640 }
641 if (int ret = modifyExplicitNetworkRule(netId, table, permission, INVALID_UID, INVALID_UID,
642 add)) {
643 return ret;
644 }
645 if (int ret = modifyOutputInterfaceRule(interface, table, permission, INVALID_UID, INVALID_UID,
646 add)) {
647 return ret;
648 }
649 return modifyImplicitNetworkRule(netId, table, permission, add);
650}
651
652WARN_UNUSED_RESULT int modifyVirtualNetwork(unsigned netId, const char* interface,
Sreeram Ramachandran95684ba2014-07-23 13:27:31 -0700653 const UidRanges& uidRanges, bool secure, bool add,
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700654 bool modifyNonUidBasedRules) {
655 uint32_t table = getRouteTableForInterface(interface);
656 if (table == RT_TABLE_UNSPEC) {
657 return -ESRCH;
658 }
659
Sreeram Ramachandrane09b20a2014-07-05 17:15:14 -0700660 for (const UidRanges::Range& range : uidRanges.getRanges()) {
Sreeram Ramachandran95684ba2014-07-23 13:27:31 -0700661 if (int ret = modifyVpnUidRangeRule(table, range.first, range.second, secure, add)) {
Sreeram Ramachandranfa9f4dc2014-07-22 18:16:44 -0700662 return ret;
663 }
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700664 if (int ret = modifyExplicitNetworkRule(netId, table, PERMISSION_NONE, range.first,
665 range.second, add)) {
Sreeram Ramachandranb1425cc2014-06-23 18:54:27 -0700666 return ret;
667 }
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700668 if (int ret = modifyOutputInterfaceRule(interface, table, PERMISSION_NONE, range.first,
669 range.second, add)) {
670 return ret;
671 }
Sreeram Ramachandran4043f012014-06-23 12:41:37 -0700672 }
673
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700674 if (modifyNonUidBasedRules) {
675 if (int ret = modifyIncomingPacketMark(netId, interface, PERMISSION_NONE, add)) {
Sreeram Ramachandraneb27b7e2014-07-01 14:30:30 -0700676 return ret;
677 }
Sreeram Ramachandran111bec22014-07-22 18:51:06 -0700678 if (int ret = modifyVpnOutputToLocalRule(interface, add)) {
679 return ret;
680 }
Sreeram Ramachandran95684ba2014-07-23 13:27:31 -0700681 if (int ret = modifyVpnSystemPermissionRule(netId, table, secure, add)) {
Sreeram Ramachandranb1425cc2014-06-23 18:54:27 -0700682 return ret;
683 }
Sreeram Ramachandranfa9f4dc2014-07-22 18:16:44 -0700684 return modifyExplicitNetworkRule(netId, table, PERMISSION_NONE, UID_ROOT, UID_ROOT, add);
Sreeram Ramachandranb1425cc2014-06-23 18:54:27 -0700685 }
686
687 return 0;
Sreeram Ramachandran4043f012014-06-23 12:41:37 -0700688}
689
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700690WARN_UNUSED_RESULT int modifyDefaultNetwork(uint16_t action, const char* interface,
691 Permission permission) {
Sreeram Ramachandran9c0d3132014-04-10 20:35:04 -0700692 uint32_t table = getRouteTableForInterface(interface);
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700693 if (table == RT_TABLE_UNSPEC) {
Lorenzo Colitti96f261e2014-06-23 15:09:54 +0900694 return -ESRCH;
Sreeram Ramachandran9c0d3132014-04-10 20:35:04 -0700695 }
696
Sreeram Ramachandran122f5812014-05-11 20:29:49 -0700697 Fwmark fwmark;
Sreeram Ramachandran122f5812014-05-11 20:29:49 -0700698 Fwmark mask;
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700699
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700700 fwmark.netId = NETID_UNSET;
Sreeram Ramachandran122f5812014-05-11 20:29:49 -0700701 mask.netId = FWMARK_NET_ID_MASK;
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700702
703 fwmark.permission = permission;
Sreeram Ramachandran122f5812014-05-11 20:29:49 -0700704 mask.permission = permission;
705
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700706 return modifyIpRule(action, RULE_PRIORITY_DEFAULT_NETWORK, table, fwmark.intValue,
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700707 mask.intValue);
Sreeram Ramachandran7619e1b2014-04-15 14:23:08 -0700708}
709
Sreeram Ramachandranfa9f4dc2014-07-22 18:16:44 -0700710WARN_UNUSED_RESULT int modifyTetheredNetwork(uint16_t action, const char* inputInterface,
711 const char* outputInterface) {
712 uint32_t table = getRouteTableForInterface(outputInterface);
713 if (table == RT_TABLE_UNSPEC) {
714 return -ESRCH;
715 }
716
717 return modifyIpRule(action, RULE_PRIORITY_TETHERING, table, MARK_UNSET, MARK_UNSET,
718 inputInterface, OIF_NONE, INVALID_UID, INVALID_UID);
719}
720
Sreeram Ramachandranb717e742014-07-19 00:22:15 -0700721// Returns 0 on success or negative errno on failure.
722WARN_UNUSED_RESULT int flushRules() {
723 for (size_t i = 0; i < ARRAY_SIZE(IP_VERSIONS); ++i) {
724 const char* argv[] = {
725 IP_PATH,
726 IP_VERSIONS[i],
727 "rule",
728 "flush",
729 };
730 if (android_fork_execvp(ARRAY_SIZE(argv), const_cast<char**>(argv), NULL, false, false)) {
731 ALOGE("failed to flush rules");
732 return -EREMOTEIO;
733 }
734 }
735 return 0;
736}
737
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700738// 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 +0900739// route, to the main table as well.
740// Returns 0 on success or negative errno on failure.
Sreeram Ramachandraneb27b7e2014-07-01 14:30:30 -0700741WARN_UNUSED_RESULT int modifyRoute(uint16_t action, const char* interface, const char* destination,
742 const char* nexthop, RouteController::TableType tableType) {
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700743 uint32_t table;
Sreeram Ramachandran38b7af12014-05-22 14:21:49 -0700744 switch (tableType) {
745 case RouteController::INTERFACE: {
746 table = getRouteTableForInterface(interface);
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700747 if (table == RT_TABLE_UNSPEC) {
748 return -ESRCH;
749 }
Sreeram Ramachandran38b7af12014-05-22 14:21:49 -0700750 break;
751 }
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700752 case RouteController::LOCAL_NETWORK: {
753 table = ROUTE_TABLE_LOCAL_NETWORK;
754 break;
755 }
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700756 case RouteController::LEGACY_NETWORK: {
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -0700757 table = ROUTE_TABLE_LEGACY_NETWORK;
Sreeram Ramachandran38b7af12014-05-22 14:21:49 -0700758 break;
759 }
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700760 case RouteController::LEGACY_SYSTEM: {
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -0700761 table = ROUTE_TABLE_LEGACY_SYSTEM;
Sreeram Ramachandran38b7af12014-05-22 14:21:49 -0700762 break;
763 }
764 }
Sreeram Ramachandran9c0d3132014-04-10 20:35:04 -0700765
Lorenzo Colittif7fc8ec2014-06-18 00:41:58 +0900766 int ret = modifyIpRoute(action, table, interface, destination, nexthop);
Sreeram Ramachandran1077d292014-06-27 06:42:11 -0700767 // We allow apps to call requestRouteToHost() multiple times with the same route, so ignore
768 // EEXIST failures when adding routes to legacy tables.
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700769 if (ret && !(action == RTM_NEWROUTE && ret == -EEXIST &&
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700770 (tableType == RouteController::LEGACY_NETWORK ||
771 tableType == RouteController::LEGACY_SYSTEM))) {
Lorenzo Colittif7fc8ec2014-06-18 00:41:58 +0900772 return ret;
Sreeram Ramachandranc9213372014-04-16 12:32:18 -0700773 }
774
775 // 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 +0900776 // let the kernel find it when validating nexthops when global routes are added.
777 if (!nexthop) {
778 ret = modifyIpRoute(action, RT_TABLE_MAIN, interface, destination, NULL);
779 // A failure with action == ADD && errno == EEXIST means that the route already exists in
780 // the main table, perhaps because the kernel added it automatically as part of adding the
781 // IP address to the interface. Ignore this, but complain about everything else.
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700782 if (ret && !(action == RTM_NEWROUTE && ret == -EEXIST)) {
Lorenzo Colittif7fc8ec2014-06-18 00:41:58 +0900783 return ret;
784 }
Sreeram Ramachandranc9213372014-04-16 12:32:18 -0700785 }
786
Lorenzo Colittif7fc8ec2014-06-18 00:41:58 +0900787 return 0;
Sreeram Ramachandran9c0d3132014-04-10 20:35:04 -0700788}
789
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700790// Returns 0 on success or negative errno on failure.
791WARN_UNUSED_RESULT int flushRoutes(const char* interface) {
Sreeram Ramachandran92b66c42014-04-15 14:28:55 -0700792 uint32_t table = getRouteTableForInterface(interface);
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700793 if (table == RT_TABLE_UNSPEC) {
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700794 return -ESRCH;
Sreeram Ramachandran92b66c42014-04-15 14:28:55 -0700795 }
796
Lorenzo Colitti357e5622014-06-17 16:14:17 +0900797 char tableString[UINT32_STRLEN];
798 snprintf(tableString, sizeof(tableString), "%u", table);
799
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700800 for (size_t i = 0; i < ARRAY_SIZE(IP_VERSIONS); ++i) {
Lorenzo Colitti357e5622014-06-17 16:14:17 +0900801 const char* argv[] = {
802 IP_PATH,
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700803 IP_VERSIONS[i],
Sreeram Ramachandran72999d62014-07-02 18:06:34 -0700804 "route",
Lorenzo Colitti357e5622014-06-17 16:14:17 +0900805 "flush",
806 "table",
807 tableString,
808 };
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700809 if (android_fork_execvp(ARRAY_SIZE(argv), const_cast<char**>(argv), NULL, false, false)) {
810 ALOGE("failed to flush routes");
811 return -EREMOTEIO;
Lorenzo Colitti357e5622014-06-17 16:14:17 +0900812 }
813 }
814
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -0700815 interfaceToTable.erase(interface);
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700816 return 0;
Sreeram Ramachandran92b66c42014-04-15 14:28:55 -0700817}
818
Sreeram Ramachandran5c181bf2014-04-07 14:10:04 -0700819} // namespace
820
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700821int RouteController::Init(unsigned localNetId) {
Sreeram Ramachandranb717e742014-07-19 00:22:15 -0700822 if (int ret = flushRules()) {
823 return ret;
824 }
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700825 if (int ret = addLegacyRouteRules()) {
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700826 return ret;
827 }
Sreeram Ramachandranfa9f4dc2014-07-22 18:16:44 -0700828 if (int ret = addLocalNetworkRules(localNetId)) {
829 return ret;
830 }
831 if (int ret = addDirectlyConnectedRule()) {
832 return ret;
833 }
Sreeram Ramachandranb717e742014-07-19 00:22:15 -0700834 if (int ret = addUnreachableRule()) {
835 return ret;
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700836 }
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -0700837 updateTableNamesFile();
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700838 return 0;
Sreeram Ramachandran8fe9c8e2014-04-16 12:08:05 -0700839}
840
Sreeram Ramachandran6a773532014-07-11 09:10:20 -0700841int RouteController::addInterfaceToLocalNetwork(unsigned netId, const char* interface) {
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700842 return modifyLocalNetwork(netId, interface, ACTION_ADD);
Sreeram Ramachandran6a773532014-07-11 09:10:20 -0700843}
844
845int RouteController::removeInterfaceFromLocalNetwork(unsigned netId, const char* interface) {
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700846 return modifyLocalNetwork(netId, interface, ACTION_DEL);
Sreeram Ramachandran6a773532014-07-11 09:10:20 -0700847}
848
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700849int RouteController::addInterfaceToPhysicalNetwork(unsigned netId, const char* interface,
850 Permission permission) {
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -0700851 if (int ret = modifyPhysicalNetwork(netId, interface, permission, ACTION_ADD)) {
852 return ret;
853 }
854 updateTableNamesFile();
855 return 0;
Sreeram Ramachandran5c181bf2014-04-07 14:10:04 -0700856}
857
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700858int RouteController::removeInterfaceFromPhysicalNetwork(unsigned netId, const char* interface,
859 Permission permission) {
860 if (int ret = modifyPhysicalNetwork(netId, interface, permission, ACTION_DEL)) {
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700861 return ret;
862 }
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -0700863 if (int ret = flushRoutes(interface)) {
864 return ret;
865 }
866 updateTableNamesFile();
867 return 0;
Sreeram Ramachandran379bd332014-04-10 19:58:06 -0700868}
869
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700870int RouteController::addInterfaceToVirtualNetwork(unsigned netId, const char* interface,
Sreeram Ramachandran95684ba2014-07-23 13:27:31 -0700871 bool secure, const UidRanges& uidRanges) {
872 if (int ret = modifyVirtualNetwork(netId, interface, uidRanges, secure, ACTION_ADD,
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -0700873 MODIFY_NON_UID_BASED_RULES)) {
874 return ret;
875 }
876 updateTableNamesFile();
877 return 0;
Sreeram Ramachandran4043f012014-06-23 12:41:37 -0700878}
879
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700880int RouteController::removeInterfaceFromVirtualNetwork(unsigned netId, const char* interface,
Sreeram Ramachandran95684ba2014-07-23 13:27:31 -0700881 bool secure, const UidRanges& uidRanges) {
882 if (int ret = modifyVirtualNetwork(netId, interface, uidRanges, secure, ACTION_DEL,
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700883 MODIFY_NON_UID_BASED_RULES)) {
Sreeram Ramachandran4043f012014-06-23 12:41:37 -0700884 return ret;
885 }
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -0700886 if (int ret = flushRoutes(interface)) {
887 return ret;
888 }
889 updateTableNamesFile();
890 return 0;
Sreeram Ramachandran4043f012014-06-23 12:41:37 -0700891}
892
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700893int RouteController::modifyPhysicalNetworkPermission(unsigned netId, const char* interface,
894 Permission oldPermission,
895 Permission newPermission) {
Sreeram Ramachandran379bd332014-04-10 19:58:06 -0700896 // Add the new rules before deleting the old ones, to avoid race conditions.
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700897 if (int ret = modifyPhysicalNetwork(netId, interface, newPermission, ACTION_ADD)) {
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700898 return ret;
899 }
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700900 return modifyPhysicalNetwork(netId, interface, oldPermission, ACTION_DEL);
Sreeram Ramachandranb1425cc2014-06-23 18:54:27 -0700901}
902
Sreeram Ramachandran95684ba2014-07-23 13:27:31 -0700903int RouteController::addUsersToVirtualNetwork(unsigned netId, const char* interface, bool secure,
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700904 const UidRanges& uidRanges) {
Sreeram Ramachandran95684ba2014-07-23 13:27:31 -0700905 return modifyVirtualNetwork(netId, interface, uidRanges, secure, ACTION_ADD,
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700906 !MODIFY_NON_UID_BASED_RULES);
Sreeram Ramachandranb1425cc2014-06-23 18:54:27 -0700907}
908
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700909int RouteController::removeUsersFromVirtualNetwork(unsigned netId, const char* interface,
Sreeram Ramachandran95684ba2014-07-23 13:27:31 -0700910 bool secure, const UidRanges& uidRanges) {
911 return modifyVirtualNetwork(netId, interface, uidRanges, secure, ACTION_DEL,
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700912 !MODIFY_NON_UID_BASED_RULES);
Sreeram Ramachandran9c0d3132014-04-10 20:35:04 -0700913}
914
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700915int RouteController::addInterfaceToDefaultNetwork(const char* interface, Permission permission) {
916 return modifyDefaultNetwork(RTM_NEWRULE, interface, permission);
Sreeram Ramachandran9c0d3132014-04-10 20:35:04 -0700917}
918
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700919int RouteController::removeInterfaceFromDefaultNetwork(const char* interface,
920 Permission permission) {
921 return modifyDefaultNetwork(RTM_DELRULE, interface, permission);
Sreeram Ramachandran5c181bf2014-04-07 14:10:04 -0700922}
Sreeram Ramachandran7619e1b2014-04-15 14:23:08 -0700923
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700924int RouteController::addRoute(const char* interface, const char* destination, const char* nexthop,
Sreeram Ramachandraneb27b7e2014-07-01 14:30:30 -0700925 TableType tableType) {
926 return modifyRoute(RTM_NEWROUTE, interface, destination, nexthop, tableType);
Sreeram Ramachandran7619e1b2014-04-15 14:23:08 -0700927}
928
Lorenzo Colittif7fc8ec2014-06-18 00:41:58 +0900929int RouteController::removeRoute(const char* interface, const char* destination,
Sreeram Ramachandraneb27b7e2014-07-01 14:30:30 -0700930 const char* nexthop, TableType tableType) {
931 return modifyRoute(RTM_DELROUTE, interface, destination, nexthop, tableType);
Sreeram Ramachandran7619e1b2014-04-15 14:23:08 -0700932}
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700933
934int RouteController::enableTethering(const char* inputInterface, const char* outputInterface) {
Sreeram Ramachandranfa9f4dc2014-07-22 18:16:44 -0700935 return modifyTetheredNetwork(RTM_NEWRULE, inputInterface, outputInterface);
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700936}
937
938int RouteController::disableTethering(const char* inputInterface, const char* outputInterface) {
Sreeram Ramachandranfa9f4dc2014-07-22 18:16:44 -0700939 return modifyTetheredNetwork(RTM_DELRULE, inputInterface, outputInterface);
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700940}