blob: fca70a6488a3d95f26799ae24daa060c26252f30 [file] [log] [blame]
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 Ramachandran48e19b02014-07-22 22:23:20 -070049const uint32_t RULE_PRIORITY_VPN_FALLTHROUGH = 21000;
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -070050const uint32_t RULE_PRIORITY_DEFAULT_NETWORK = 22000;
Lorenzo Colittia2c23052014-07-29 09:25:44 +000051const uint32_t RULE_PRIORITY_DIRECTLY_CONNECTED = 23000;
Lorenzo Colittidb74dba2014-07-29 18:26:21 +090052const uint32_t RULE_PRIORITY_UNREACHABLE = 32000;
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
Sreeram Ramachandrande5d5df2014-07-26 18:43:25 -0700357 uint8_t type = RTN_UNICAST;
Lorenzo Colittiba25df92014-06-18 00:22:17 +0900358 uint32_t ifindex;
Lorenzo Colittiba25df92014-06-18 00:22:17 +0900359 uint8_t rawNexthop[sizeof(in6_addr)];
Sreeram Ramachandrande5d5df2014-07-26 18:43:25 -0700360
361 if (nexthop && !strcmp(nexthop, "unreachable")) {
362 type = RTN_UNREACHABLE;
363 // 'interface' is likely non-NULL, as the caller (modifyRoute()) likely used it to lookup
364 // the table number. But it's an error to specify an interface ("dev ...") or a nexthop for
365 // unreachable routes, so nuke them. (IPv6 allows them to be specified; IPv4 doesn't.)
366 interface = OIF_NONE;
367 nexthop = NULL;
368 } else {
369 // If an interface was specified, find the ifindex.
370 if (interface != OIF_NONE) {
371 ifindex = if_nametoindex(interface);
372 if (!ifindex) {
373 ALOGE("cannot find interface %s", interface);
374 return -ENODEV;
375 }
376 }
377
378 // If a nexthop was specified, parse it as the same family as the prefix.
379 if (nexthop && inet_pton(family, nexthop, rawNexthop) <= 0) {
380 ALOGE("inet_pton failed for nexthop %s", nexthop);
381 return -EINVAL;
382 }
Lorenzo Colittiba25df92014-06-18 00:22:17 +0900383 }
384
Lorenzo Colitti4753afd2014-06-20 23:03:29 +0900385 // Assemble a rtmsg and put it in an array of iovec structures.
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700386 rtmsg route = {
Lorenzo Colittiba25df92014-06-18 00:22:17 +0900387 .rtm_protocol = RTPROT_STATIC,
Sreeram Ramachandrande5d5df2014-07-26 18:43:25 -0700388 .rtm_type = type,
Lorenzo Colittiba25df92014-06-18 00:22:17 +0900389 .rtm_family = family,
390 .rtm_dst_len = prefixLength,
Sreeram Ramachandran2bff72e2014-07-18 13:03:47 -0700391 .rtm_scope = static_cast<uint8_t>(nexthop ? RT_SCOPE_UNIVERSE : RT_SCOPE_LINK),
Lorenzo Colittiba25df92014-06-18 00:22:17 +0900392 };
Lorenzo Colitti4753afd2014-06-20 23:03:29 +0900393
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700394 rtattr rtaDst = { U16_RTA_LENGTH(rawLength), RTA_DST };
395 rtattr rtaGateway = { U16_RTA_LENGTH(rawLength), RTA_GATEWAY };
Lorenzo Colittiba25df92014-06-18 00:22:17 +0900396
397 iovec iov[] = {
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700398 { NULL, 0 },
399 { &route, sizeof(route) },
400 { &RTATTR_TABLE, sizeof(RTATTR_TABLE) },
401 { &table, sizeof(table) },
402 { &rtaDst, sizeof(rtaDst) },
403 { rawAddress, static_cast<size_t>(rawLength) },
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700404 { &RTATTR_OIF, interface != OIF_NONE ? sizeof(RTATTR_OIF) : 0 },
405 { &ifindex, interface != OIF_NONE ? sizeof(ifindex) : 0 },
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700406 { &rtaGateway, nexthop ? sizeof(rtaGateway) : 0 },
407 { rawNexthop, nexthop ? static_cast<size_t>(rawLength) : 0 },
Lorenzo Colittiba25df92014-06-18 00:22:17 +0900408 };
Lorenzo Colittiba25df92014-06-18 00:22:17 +0900409
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700410 uint16_t flags = (action == RTM_NEWROUTE) ? NETLINK_CREATE_REQUEST_FLAGS :
411 NETLINK_REQUEST_FLAGS;
Lorenzo Colitti4753afd2014-06-20 23:03:29 +0900412 return sendNetlinkRequest(action, flags, iov, ARRAY_SIZE(iov));
Sreeram Ramachandran7619e1b2014-04-15 14:23:08 -0700413}
414
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700415// An iptables rule to mark incoming packets on a network with the netId of the network.
416//
417// This is so that the kernel can:
418// + Use the right fwmark for (and thus correctly route) replies (e.g.: TCP RST, ICMP errors, ping
419// replies, SYN-ACKs, etc).
420// + Mark sockets that accept connections from this interface so that the connection stays on the
421// same interface.
422WARN_UNUSED_RESULT int modifyIncomingPacketMark(unsigned netId, const char* interface,
423 Permission permission, bool add) {
424 Fwmark fwmark;
425
426 fwmark.netId = netId;
427 fwmark.explicitlySelected = true;
428 fwmark.protectedFromVpn = true;
429 fwmark.permission = permission;
430
Sreeram Ramachandranb1425cc2014-06-23 18:54:27 -0700431 char markString[UINT32_HEX_STRLEN];
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700432 snprintf(markString, sizeof(markString), "0x%x", fwmark.intValue);
433
Sreeram Ramachandranb1425cc2014-06-23 18:54:27 -0700434 if (execIptables(V4V6, "-t", "mangle", add ? "-A" : "-D", "INPUT", "-i", interface, "-j",
435 "MARK", "--set-mark", markString, NULL)) {
436 ALOGE("failed to change iptables rule that sets incoming packet mark");
437 return -EREMOTEIO;
438 }
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700439
Sreeram Ramachandranb1425cc2014-06-23 18:54:27 -0700440 return 0;
441}
442
Sreeram Ramachandran111bec22014-07-22 18:51:06 -0700443// A rule to route responses to the local network forwarded via the VPN.
444//
445// When a VPN is in effect, packets from the local network to upstream networks are forwarded into
446// the VPN's tunnel interface. When the VPN forwards the responses, they emerge out of the tunnel.
447WARN_UNUSED_RESULT int modifyVpnOutputToLocalRule(const char* vpnInterface, bool add) {
448 return modifyIpRule(add ? RTM_NEWRULE : RTM_DELRULE, RULE_PRIORITY_VPN_OUTPUT_TO_LOCAL,
449 ROUTE_TABLE_LOCAL_NETWORK, MARK_UNSET, MARK_UNSET, vpnInterface, OIF_NONE,
450 INVALID_UID, INVALID_UID);
451}
452
Sreeram Ramachandranfa9f4dc2014-07-22 18:16:44 -0700453// A rule to route all traffic from a given set of UIDs to go over the VPN.
454//
455// Notice that this rule doesn't use the netId. I.e., no matter what netId the user's socket may
456// have, if they are subject to this VPN, their traffic has to go through it. Allows the traffic to
457// bypass the VPN if the protectedFromVpn bit is set.
458WARN_UNUSED_RESULT int modifyVpnUidRangeRule(uint32_t table, uid_t uidStart, uid_t uidEnd,
Sreeram Ramachandran95684ba2014-07-23 13:27:31 -0700459 bool secure, bool add) {
Sreeram Ramachandranfa9f4dc2014-07-22 18:16:44 -0700460 Fwmark fwmark;
461 Fwmark mask;
462
463 fwmark.protectedFromVpn = false;
464 mask.protectedFromVpn = true;
465
Sreeram Ramachandran95684ba2014-07-23 13:27:31 -0700466 uint32_t priority;
467
468 if (secure) {
469 priority = RULE_PRIORITY_SECURE_VPN;
470 } else {
471 priority = RULE_PRIORITY_BYPASSABLE_VPN;
472
473 fwmark.explicitlySelected = false;
474 mask.explicitlySelected = true;
475 }
476
477 return modifyIpRule(add ? RTM_NEWRULE : RTM_DELRULE, priority, table, fwmark.intValue,
478 mask.intValue, IIF_NONE, OIF_NONE, uidStart, uidEnd);
Sreeram Ramachandranfa9f4dc2014-07-22 18:16:44 -0700479}
480
481// A rule to allow system apps to send traffic over this VPN even if they are not part of the target
482// set of UIDs.
483//
484// This is needed for DnsProxyListener to correctly resolve a request for a user who is in the
485// target set, but where the DnsProxyListener itself is not.
Sreeram Ramachandran95684ba2014-07-23 13:27:31 -0700486WARN_UNUSED_RESULT int modifyVpnSystemPermissionRule(unsigned netId, uint32_t table, bool secure,
487 bool add) {
Sreeram Ramachandranfa9f4dc2014-07-22 18:16:44 -0700488 Fwmark fwmark;
489 Fwmark mask;
490
491 fwmark.netId = netId;
492 mask.netId = FWMARK_NET_ID_MASK;
493
494 fwmark.permission = PERMISSION_SYSTEM;
495 mask.permission = PERMISSION_SYSTEM;
496
Sreeram Ramachandran95684ba2014-07-23 13:27:31 -0700497 uint32_t priority = secure ? RULE_PRIORITY_SECURE_VPN : RULE_PRIORITY_BYPASSABLE_VPN;
498
499 return modifyIpRule(add ? RTM_NEWRULE : RTM_DELRULE, priority, table, fwmark.intValue,
500 mask.intValue);
Sreeram Ramachandranfa9f4dc2014-07-22 18:16:44 -0700501}
502
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700503// A rule to route traffic based on an explicitly chosen network.
504//
505// Supports apps that use the multinetwork APIs to restrict their traffic to a network.
506//
507// Even though we check permissions at the time we set a netId into the fwmark of a socket, we need
508// to check it again in the rules here, because a network's permissions may have been updated via
509// modifyNetworkPermission().
510WARN_UNUSED_RESULT int modifyExplicitNetworkRule(unsigned netId, uint32_t table,
511 Permission permission, uid_t uidStart,
512 uid_t uidEnd, bool add) {
Sreeram Ramachandraneb27b7e2014-07-01 14:30:30 -0700513 Fwmark fwmark;
514 Fwmark mask;
515
516 fwmark.netId = netId;
517 mask.netId = FWMARK_NET_ID_MASK;
518
Sreeram Ramachandran122f5812014-05-11 20:29:49 -0700519 fwmark.explicitlySelected = true;
520 mask.explicitlySelected = true;
Sreeram Ramachandran5c181bf2014-04-07 14:10:04 -0700521
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700522 fwmark.permission = permission;
523 mask.permission = permission;
Sreeram Ramachandraneb27b7e2014-07-01 14:30:30 -0700524
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700525 return modifyIpRule(add ? RTM_NEWRULE : RTM_DELRULE, RULE_PRIORITY_EXPLICIT_NETWORK, table,
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700526 fwmark.intValue, mask.intValue, IIF_NONE, OIF_NONE, uidStart, uidEnd);
Sreeram Ramachandran5c181bf2014-04-07 14:10:04 -0700527}
528
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700529// A rule to route traffic based on a chosen outgoing interface.
530//
531// Supports apps that use SO_BINDTODEVICE or IP_PKTINFO options and the kernel that already knows
532// the outgoing interface (typically for link-local communications).
533WARN_UNUSED_RESULT int modifyOutputInterfaceRule(const char* interface, uint32_t table,
534 Permission permission, uid_t uidStart,
535 uid_t uidEnd, bool add) {
536 Fwmark fwmark;
537 Fwmark mask;
Sreeram Ramachandran4043f012014-06-23 12:41:37 -0700538
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700539 fwmark.permission = permission;
540 mask.permission = permission;
Sreeram Ramachandranb1425cc2014-06-23 18:54:27 -0700541
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700542 return modifyIpRule(add ? RTM_NEWRULE : RTM_DELRULE, RULE_PRIORITY_OUTPUT_INTERFACE, table,
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700543 fwmark.intValue, mask.intValue, IIF_NONE, interface, uidStart, uidEnd);
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700544}
545
546// A rule to route traffic based on the chosen network.
547//
548// This is for sockets that have not explicitly requested a particular network, but have been
549// bound to one when they called connect(). This ensures that sockets connected on a particular
550// network stay on that network even if the default network changes.
551WARN_UNUSED_RESULT int modifyImplicitNetworkRule(unsigned netId, uint32_t table,
552 Permission permission, bool add) {
553 Fwmark fwmark;
554 Fwmark mask;
555
556 fwmark.netId = netId;
557 mask.netId = FWMARK_NET_ID_MASK;
558
559 fwmark.explicitlySelected = false;
560 mask.explicitlySelected = true;
561
562 fwmark.permission = permission;
563 mask.permission = permission;
564
565 return modifyIpRule(add ? RTM_NEWRULE : RTM_DELRULE, RULE_PRIORITY_IMPLICIT_NETWORK, table,
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700566 fwmark.intValue, mask.intValue);
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700567}
568
Sreeram Ramachandran48e19b02014-07-22 22:23:20 -0700569// A rule to enable split tunnel VPNs.
570//
571// If a packet with a VPN's netId doesn't find a route in the VPN's routing table, it's allowed to
572// go over the default network, provided it wasn't explicitly restricted to the VPN and has the
573// permissions required by the default network.
574WARN_UNUSED_RESULT int modifyVpnFallthroughRule(uint16_t action, unsigned vpnNetId,
575 const char* physicalInterface,
576 Permission permission) {
577 uint32_t table = getRouteTableForInterface(physicalInterface);
578 if (table == RT_TABLE_UNSPEC) {
579 return -ESRCH;
580 }
581
582 Fwmark fwmark;
583 Fwmark mask;
584
585 fwmark.netId = vpnNetId;
586 mask.netId = FWMARK_NET_ID_MASK;
587
588 fwmark.explicitlySelected = false;
589 mask.explicitlySelected = true;
590
591 fwmark.permission = permission;
592 mask.permission = permission;
593
594 return modifyIpRule(action, RULE_PRIORITY_VPN_FALLTHROUGH, table, fwmark.intValue,
595 mask.intValue);
596}
597
Sreeram Ramachandranfa9f4dc2014-07-22 18:16:44 -0700598// Add rules to allow legacy routes added through the requestRouteToHost() API.
599WARN_UNUSED_RESULT int addLegacyRouteRules() {
Sreeram Ramachandran4043f012014-06-23 12:41:37 -0700600 Fwmark fwmark;
601 Fwmark mask;
602
Sreeram Ramachandranfa9f4dc2014-07-22 18:16:44 -0700603 fwmark.explicitlySelected = false;
604 mask.explicitlySelected = true;
Sreeram Ramachandranb1425cc2014-06-23 18:54:27 -0700605
Sreeram Ramachandranfa9f4dc2014-07-22 18:16:44 -0700606 // Rules to allow legacy routes to override the default network.
607 if (int ret = modifyIpRule(RTM_NEWRULE, RULE_PRIORITY_LEGACY_SYSTEM, ROUTE_TABLE_LEGACY_SYSTEM,
608 fwmark.intValue, mask.intValue)) {
609 return ret;
610 }
611 if (int ret = modifyIpRule(RTM_NEWRULE, RULE_PRIORITY_LEGACY_NETWORK,
612 ROUTE_TABLE_LEGACY_NETWORK, fwmark.intValue, mask.intValue)) {
613 return ret;
614 }
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700615
616 fwmark.permission = PERMISSION_SYSTEM;
617 mask.permission = PERMISSION_SYSTEM;
618
Sreeram Ramachandranfa9f4dc2014-07-22 18:16:44 -0700619 // A rule to allow legacy routes from system apps to override VPNs.
620 return modifyIpRule(RTM_NEWRULE, RULE_PRIORITY_VPN_OVERRIDE_SYSTEM, ROUTE_TABLE_LEGACY_SYSTEM,
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700621 fwmark.intValue, mask.intValue);
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700622}
623
Sreeram Ramachandranfa9f4dc2014-07-22 18:16:44 -0700624// Add rules to lookup the local network when specified explicitly or otherwise.
625WARN_UNUSED_RESULT int addLocalNetworkRules(unsigned localNetId) {
626 if (int ret = modifyExplicitNetworkRule(localNetId, ROUTE_TABLE_LOCAL_NETWORK, PERMISSION_NONE,
627 INVALID_UID, INVALID_UID, ACTION_ADD)) {
628 return ret;
Sreeram Ramachandran6a773532014-07-11 09:10:20 -0700629 }
630
Sreeram Ramachandranfa9f4dc2014-07-22 18:16:44 -0700631 Fwmark fwmark;
632 Fwmark mask;
633
634 fwmark.explicitlySelected = false;
635 mask.explicitlySelected = true;
636
637 return modifyIpRule(RTM_NEWRULE, RULE_PRIORITY_LOCAL_NETWORK, ROUTE_TABLE_LOCAL_NETWORK,
638 fwmark.intValue, mask.intValue);
639}
640
Lorenzo Colittia2c23052014-07-29 09:25:44 +0000641// Add a new rule to look up the 'main' table, with the same selectors as the "default network"
Lorenzo Colittidb74dba2014-07-29 18:26:21 +0900642// rule, but with a lower priority. We will never create routes in the main table; it should only be
643// used for directly-connected routes implicitly created by the kernel when adding IP addresses.
644// This is necessary, for example, when adding a route through a directly-connected gateway: in
645// order to add the route, there must already be a directly-connected route that covers the gateway.
Lorenzo Colittia2c23052014-07-29 09:25:44 +0000646WARN_UNUSED_RESULT int addDirectlyConnectedRule() {
647 Fwmark fwmark;
648 Fwmark mask;
649
650 fwmark.netId = NETID_UNSET;
651 mask.netId = FWMARK_NET_ID_MASK;
652
653 return modifyIpRule(RTM_NEWRULE, RULE_PRIORITY_DIRECTLY_CONNECTED, RT_TABLE_MAIN,
654 fwmark.intValue, mask.intValue, IIF_NONE, OIF_NONE, UID_ROOT, UID_ROOT);
655}
656
Lorenzo Colittidb74dba2014-07-29 18:26:21 +0900657// Add an explicit unreachable rule close to the end of the prioriy list to make it clear that
658// relying on the kernel-default "from all lookup main" rule at priority 32766 is not intended
659// behaviour. We do flush the kernel-default rules at startup, but having an explicit unreachable
660// rule will hopefully make things even clearer.
Sreeram Ramachandranfa9f4dc2014-07-22 18:16:44 -0700661WARN_UNUSED_RESULT int addUnreachableRule() {
662 return modifyIpRule(RTM_NEWRULE, RULE_PRIORITY_UNREACHABLE, RT_TABLE_UNSPEC, MARK_UNSET,
663 MARK_UNSET);
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700664}
665
666WARN_UNUSED_RESULT int modifyLocalNetwork(unsigned netId, const char* interface, bool add) {
Sreeram Ramachandran6a773532014-07-11 09:10:20 -0700667 if (int ret = modifyIncomingPacketMark(netId, interface, PERMISSION_NONE, add)) {
668 return ret;
669 }
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700670 return modifyOutputInterfaceRule(interface, ROUTE_TABLE_LOCAL_NETWORK, PERMISSION_NONE,
671 INVALID_UID, INVALID_UID, add);
Sreeram Ramachandran6a773532014-07-11 09:10:20 -0700672}
673
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700674WARN_UNUSED_RESULT int modifyPhysicalNetwork(unsigned netId, const char* interface,
675 Permission permission, bool add) {
676 uint32_t table = getRouteTableForInterface(interface);
677 if (table == RT_TABLE_UNSPEC) {
678 return -ESRCH;
679 }
680
681 if (int ret = modifyIncomingPacketMark(netId, interface, permission, add)) {
682 return ret;
683 }
684 if (int ret = modifyExplicitNetworkRule(netId, table, permission, INVALID_UID, INVALID_UID,
685 add)) {
686 return ret;
687 }
688 if (int ret = modifyOutputInterfaceRule(interface, table, permission, INVALID_UID, INVALID_UID,
689 add)) {
690 return ret;
691 }
692 return modifyImplicitNetworkRule(netId, table, permission, add);
693}
694
695WARN_UNUSED_RESULT int modifyVirtualNetwork(unsigned netId, const char* interface,
Sreeram Ramachandran95684ba2014-07-23 13:27:31 -0700696 const UidRanges& uidRanges, bool secure, bool add,
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700697 bool modifyNonUidBasedRules) {
698 uint32_t table = getRouteTableForInterface(interface);
699 if (table == RT_TABLE_UNSPEC) {
700 return -ESRCH;
701 }
702
Sreeram Ramachandrane09b20a2014-07-05 17:15:14 -0700703 for (const UidRanges::Range& range : uidRanges.getRanges()) {
Sreeram Ramachandran95684ba2014-07-23 13:27:31 -0700704 if (int ret = modifyVpnUidRangeRule(table, range.first, range.second, secure, add)) {
Sreeram Ramachandranfa9f4dc2014-07-22 18:16:44 -0700705 return ret;
706 }
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700707 if (int ret = modifyExplicitNetworkRule(netId, table, PERMISSION_NONE, range.first,
708 range.second, add)) {
Sreeram Ramachandranb1425cc2014-06-23 18:54:27 -0700709 return ret;
710 }
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700711 if (int ret = modifyOutputInterfaceRule(interface, table, PERMISSION_NONE, range.first,
712 range.second, add)) {
713 return ret;
714 }
Sreeram Ramachandran4043f012014-06-23 12:41:37 -0700715 }
716
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700717 if (modifyNonUidBasedRules) {
718 if (int ret = modifyIncomingPacketMark(netId, interface, PERMISSION_NONE, add)) {
Sreeram Ramachandraneb27b7e2014-07-01 14:30:30 -0700719 return ret;
720 }
Sreeram Ramachandran111bec22014-07-22 18:51:06 -0700721 if (int ret = modifyVpnOutputToLocalRule(interface, add)) {
722 return ret;
723 }
Sreeram Ramachandran95684ba2014-07-23 13:27:31 -0700724 if (int ret = modifyVpnSystemPermissionRule(netId, table, secure, add)) {
Sreeram Ramachandranb1425cc2014-06-23 18:54:27 -0700725 return ret;
726 }
Sreeram Ramachandranfa9f4dc2014-07-22 18:16:44 -0700727 return modifyExplicitNetworkRule(netId, table, PERMISSION_NONE, UID_ROOT, UID_ROOT, add);
Sreeram Ramachandranb1425cc2014-06-23 18:54:27 -0700728 }
729
730 return 0;
Sreeram Ramachandran4043f012014-06-23 12:41:37 -0700731}
732
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700733WARN_UNUSED_RESULT int modifyDefaultNetwork(uint16_t action, const char* interface,
734 Permission permission) {
Sreeram Ramachandran9c0d3132014-04-10 20:35:04 -0700735 uint32_t table = getRouteTableForInterface(interface);
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700736 if (table == RT_TABLE_UNSPEC) {
Lorenzo Colitti96f261e2014-06-23 15:09:54 +0900737 return -ESRCH;
Sreeram Ramachandran9c0d3132014-04-10 20:35:04 -0700738 }
739
Sreeram Ramachandran122f5812014-05-11 20:29:49 -0700740 Fwmark fwmark;
Sreeram Ramachandran122f5812014-05-11 20:29:49 -0700741 Fwmark mask;
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700742
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700743 fwmark.netId = NETID_UNSET;
Sreeram Ramachandran122f5812014-05-11 20:29:49 -0700744 mask.netId = FWMARK_NET_ID_MASK;
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700745
746 fwmark.permission = permission;
Sreeram Ramachandran122f5812014-05-11 20:29:49 -0700747 mask.permission = permission;
748
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700749 return modifyIpRule(action, RULE_PRIORITY_DEFAULT_NETWORK, table, fwmark.intValue,
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700750 mask.intValue);
Sreeram Ramachandran7619e1b2014-04-15 14:23:08 -0700751}
752
Sreeram Ramachandranfa9f4dc2014-07-22 18:16:44 -0700753WARN_UNUSED_RESULT int modifyTetheredNetwork(uint16_t action, const char* inputInterface,
754 const char* outputInterface) {
755 uint32_t table = getRouteTableForInterface(outputInterface);
756 if (table == RT_TABLE_UNSPEC) {
757 return -ESRCH;
758 }
759
760 return modifyIpRule(action, RULE_PRIORITY_TETHERING, table, MARK_UNSET, MARK_UNSET,
761 inputInterface, OIF_NONE, INVALID_UID, INVALID_UID);
762}
763
Sreeram Ramachandranb717e742014-07-19 00:22:15 -0700764// Returns 0 on success or negative errno on failure.
765WARN_UNUSED_RESULT int flushRules() {
766 for (size_t i = 0; i < ARRAY_SIZE(IP_VERSIONS); ++i) {
767 const char* argv[] = {
768 IP_PATH,
769 IP_VERSIONS[i],
770 "rule",
771 "flush",
772 };
773 if (android_fork_execvp(ARRAY_SIZE(argv), const_cast<char**>(argv), NULL, false, false)) {
774 ALOGE("failed to flush rules");
775 return -EREMOTEIO;
776 }
777 }
778 return 0;
779}
780
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700781// 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 +0900782// route, to the main table as well.
783// Returns 0 on success or negative errno on failure.
Sreeram Ramachandraneb27b7e2014-07-01 14:30:30 -0700784WARN_UNUSED_RESULT int modifyRoute(uint16_t action, const char* interface, const char* destination,
785 const char* nexthop, RouteController::TableType tableType) {
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700786 uint32_t table;
Sreeram Ramachandran38b7af12014-05-22 14:21:49 -0700787 switch (tableType) {
788 case RouteController::INTERFACE: {
789 table = getRouteTableForInterface(interface);
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700790 if (table == RT_TABLE_UNSPEC) {
791 return -ESRCH;
792 }
Sreeram Ramachandran38b7af12014-05-22 14:21:49 -0700793 break;
794 }
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700795 case RouteController::LOCAL_NETWORK: {
796 table = ROUTE_TABLE_LOCAL_NETWORK;
797 break;
798 }
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700799 case RouteController::LEGACY_NETWORK: {
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -0700800 table = ROUTE_TABLE_LEGACY_NETWORK;
Sreeram Ramachandran38b7af12014-05-22 14:21:49 -0700801 break;
802 }
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700803 case RouteController::LEGACY_SYSTEM: {
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -0700804 table = ROUTE_TABLE_LEGACY_SYSTEM;
Sreeram Ramachandran38b7af12014-05-22 14:21:49 -0700805 break;
806 }
807 }
Sreeram Ramachandran9c0d3132014-04-10 20:35:04 -0700808
Lorenzo Colittif7fc8ec2014-06-18 00:41:58 +0900809 int ret = modifyIpRoute(action, table, interface, destination, nexthop);
Sreeram Ramachandran1077d292014-06-27 06:42:11 -0700810 // We allow apps to call requestRouteToHost() multiple times with the same route, so ignore
811 // EEXIST failures when adding routes to legacy tables.
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700812 if (ret && !(action == RTM_NEWROUTE && ret == -EEXIST &&
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700813 (tableType == RouteController::LEGACY_NETWORK ||
814 tableType == RouteController::LEGACY_SYSTEM))) {
Lorenzo Colittif7fc8ec2014-06-18 00:41:58 +0900815 return ret;
Sreeram Ramachandranc9213372014-04-16 12:32:18 -0700816 }
817
Lorenzo Colittif7fc8ec2014-06-18 00:41:58 +0900818 return 0;
Sreeram Ramachandran9c0d3132014-04-10 20:35:04 -0700819}
820
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700821// Returns 0 on success or negative errno on failure.
822WARN_UNUSED_RESULT int flushRoutes(const char* interface) {
Sreeram Ramachandran92b66c42014-04-15 14:28:55 -0700823 uint32_t table = getRouteTableForInterface(interface);
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700824 if (table == RT_TABLE_UNSPEC) {
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700825 return -ESRCH;
Sreeram Ramachandran92b66c42014-04-15 14:28:55 -0700826 }
827
Lorenzo Colitti357e5622014-06-17 16:14:17 +0900828 char tableString[UINT32_STRLEN];
829 snprintf(tableString, sizeof(tableString), "%u", table);
830
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700831 for (size_t i = 0; i < ARRAY_SIZE(IP_VERSIONS); ++i) {
Lorenzo Colitti357e5622014-06-17 16:14:17 +0900832 const char* argv[] = {
833 IP_PATH,
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700834 IP_VERSIONS[i],
Sreeram Ramachandran72999d62014-07-02 18:06:34 -0700835 "route",
Lorenzo Colitti357e5622014-06-17 16:14:17 +0900836 "flush",
837 "table",
838 tableString,
839 };
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700840 if (android_fork_execvp(ARRAY_SIZE(argv), const_cast<char**>(argv), NULL, false, false)) {
841 ALOGE("failed to flush routes");
842 return -EREMOTEIO;
Lorenzo Colitti357e5622014-06-17 16:14:17 +0900843 }
844 }
845
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -0700846 interfaceToTable.erase(interface);
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700847 return 0;
Sreeram Ramachandran92b66c42014-04-15 14:28:55 -0700848}
849
Sreeram Ramachandran5c181bf2014-04-07 14:10:04 -0700850} // namespace
851
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700852int RouteController::Init(unsigned localNetId) {
Sreeram Ramachandranb717e742014-07-19 00:22:15 -0700853 if (int ret = flushRules()) {
854 return ret;
855 }
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700856 if (int ret = addLegacyRouteRules()) {
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700857 return ret;
858 }
Sreeram Ramachandranfa9f4dc2014-07-22 18:16:44 -0700859 if (int ret = addLocalNetworkRules(localNetId)) {
860 return ret;
861 }
Lorenzo Colittia2c23052014-07-29 09:25:44 +0000862 if (int ret = addDirectlyConnectedRule()) {
863 return ret;
864 }
Sreeram Ramachandranb717e742014-07-19 00:22:15 -0700865 if (int ret = addUnreachableRule()) {
866 return ret;
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700867 }
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -0700868 updateTableNamesFile();
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700869 return 0;
Sreeram Ramachandran8fe9c8e2014-04-16 12:08:05 -0700870}
871
Sreeram Ramachandran6a773532014-07-11 09:10:20 -0700872int RouteController::addInterfaceToLocalNetwork(unsigned netId, const char* interface) {
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700873 return modifyLocalNetwork(netId, interface, ACTION_ADD);
Sreeram Ramachandran6a773532014-07-11 09:10:20 -0700874}
875
876int RouteController::removeInterfaceFromLocalNetwork(unsigned netId, const char* interface) {
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700877 return modifyLocalNetwork(netId, interface, ACTION_DEL);
Sreeram Ramachandran6a773532014-07-11 09:10:20 -0700878}
879
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700880int RouteController::addInterfaceToPhysicalNetwork(unsigned netId, const char* interface,
881 Permission permission) {
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -0700882 if (int ret = modifyPhysicalNetwork(netId, interface, permission, ACTION_ADD)) {
883 return ret;
884 }
885 updateTableNamesFile();
886 return 0;
Sreeram Ramachandran5c181bf2014-04-07 14:10:04 -0700887}
888
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700889int RouteController::removeInterfaceFromPhysicalNetwork(unsigned netId, const char* interface,
890 Permission permission) {
891 if (int ret = modifyPhysicalNetwork(netId, interface, permission, ACTION_DEL)) {
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700892 return ret;
893 }
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -0700894 if (int ret = flushRoutes(interface)) {
895 return ret;
896 }
897 updateTableNamesFile();
898 return 0;
Sreeram Ramachandran379bd332014-04-10 19:58:06 -0700899}
900
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700901int RouteController::addInterfaceToVirtualNetwork(unsigned netId, const char* interface,
Sreeram Ramachandran95684ba2014-07-23 13:27:31 -0700902 bool secure, const UidRanges& uidRanges) {
903 if (int ret = modifyVirtualNetwork(netId, interface, uidRanges, secure, ACTION_ADD,
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -0700904 MODIFY_NON_UID_BASED_RULES)) {
905 return ret;
906 }
907 updateTableNamesFile();
908 return 0;
Sreeram Ramachandran4043f012014-06-23 12:41:37 -0700909}
910
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700911int RouteController::removeInterfaceFromVirtualNetwork(unsigned netId, const char* interface,
Sreeram Ramachandran95684ba2014-07-23 13:27:31 -0700912 bool secure, const UidRanges& uidRanges) {
913 if (int ret = modifyVirtualNetwork(netId, interface, uidRanges, secure, ACTION_DEL,
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700914 MODIFY_NON_UID_BASED_RULES)) {
Sreeram Ramachandran4043f012014-06-23 12:41:37 -0700915 return ret;
916 }
Sreeram Ramachandran4acd34a2014-07-07 22:11:37 -0700917 if (int ret = flushRoutes(interface)) {
918 return ret;
919 }
920 updateTableNamesFile();
921 return 0;
Sreeram Ramachandran4043f012014-06-23 12:41:37 -0700922}
923
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700924int RouteController::modifyPhysicalNetworkPermission(unsigned netId, const char* interface,
925 Permission oldPermission,
926 Permission newPermission) {
Sreeram Ramachandran379bd332014-04-10 19:58:06 -0700927 // Add the new rules before deleting the old ones, to avoid race conditions.
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700928 if (int ret = modifyPhysicalNetwork(netId, interface, newPermission, ACTION_ADD)) {
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700929 return ret;
930 }
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700931 return modifyPhysicalNetwork(netId, interface, oldPermission, ACTION_DEL);
Sreeram Ramachandranb1425cc2014-06-23 18:54:27 -0700932}
933
Sreeram Ramachandran95684ba2014-07-23 13:27:31 -0700934int RouteController::addUsersToVirtualNetwork(unsigned netId, const char* interface, bool secure,
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700935 const UidRanges& uidRanges) {
Sreeram Ramachandran95684ba2014-07-23 13:27:31 -0700936 return modifyVirtualNetwork(netId, interface, uidRanges, secure, ACTION_ADD,
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700937 !MODIFY_NON_UID_BASED_RULES);
Sreeram Ramachandranb1425cc2014-06-23 18:54:27 -0700938}
939
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700940int RouteController::removeUsersFromVirtualNetwork(unsigned netId, const char* interface,
Sreeram Ramachandran95684ba2014-07-23 13:27:31 -0700941 bool secure, const UidRanges& uidRanges) {
942 return modifyVirtualNetwork(netId, interface, uidRanges, secure, ACTION_DEL,
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700943 !MODIFY_NON_UID_BASED_RULES);
Sreeram Ramachandran9c0d3132014-04-10 20:35:04 -0700944}
945
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700946int RouteController::addInterfaceToDefaultNetwork(const char* interface, Permission permission) {
947 return modifyDefaultNetwork(RTM_NEWRULE, interface, permission);
Sreeram Ramachandran9c0d3132014-04-10 20:35:04 -0700948}
949
Sreeram Ramachandran5009d5e2014-07-03 12:20:48 -0700950int RouteController::removeInterfaceFromDefaultNetwork(const char* interface,
951 Permission permission) {
952 return modifyDefaultNetwork(RTM_DELRULE, interface, permission);
Sreeram Ramachandran5c181bf2014-04-07 14:10:04 -0700953}
Sreeram Ramachandran7619e1b2014-04-15 14:23:08 -0700954
Sreeram Ramachandranf4f6c8d2014-06-23 09:54:06 -0700955int RouteController::addRoute(const char* interface, const char* destination, const char* nexthop,
Sreeram Ramachandraneb27b7e2014-07-01 14:30:30 -0700956 TableType tableType) {
957 return modifyRoute(RTM_NEWROUTE, interface, destination, nexthop, tableType);
Sreeram Ramachandran7619e1b2014-04-15 14:23:08 -0700958}
959
Lorenzo Colittif7fc8ec2014-06-18 00:41:58 +0900960int RouteController::removeRoute(const char* interface, const char* destination,
Sreeram Ramachandraneb27b7e2014-07-01 14:30:30 -0700961 const char* nexthop, TableType tableType) {
962 return modifyRoute(RTM_DELROUTE, interface, destination, nexthop, tableType);
Sreeram Ramachandran7619e1b2014-04-15 14:23:08 -0700963}
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700964
965int RouteController::enableTethering(const char* inputInterface, const char* outputInterface) {
Sreeram Ramachandranfa9f4dc2014-07-22 18:16:44 -0700966 return modifyTetheredNetwork(RTM_NEWRULE, inputInterface, outputInterface);
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700967}
968
969int RouteController::disableTethering(const char* inputInterface, const char* outputInterface) {
Sreeram Ramachandranfa9f4dc2014-07-22 18:16:44 -0700970 return modifyTetheredNetwork(RTM_DELRULE, inputInterface, outputInterface);
Sreeram Ramachandran87475a12014-07-15 16:20:28 -0700971}
Sreeram Ramachandran48e19b02014-07-22 22:23:20 -0700972
973int RouteController::addVirtualNetworkFallthrough(unsigned vpnNetId, const char* physicalInterface,
974 Permission permission) {
975 return modifyVpnFallthroughRule(RTM_NEWRULE, vpnNetId, physicalInterface, permission);
976}
977
978int RouteController::removeVirtualNetworkFallthrough(unsigned vpnNetId,
979 const char* physicalInterface,
980 Permission permission) {
981 return modifyVpnFallthroughRule(RTM_DELRULE, vpnNetId, physicalInterface, permission);
982}