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Diffstat (limited to 'server/RouteController.cpp')
-rw-r--r--server/RouteController.cpp166
1 files changed, 42 insertions, 124 deletions
diff --git a/server/RouteController.cpp b/server/RouteController.cpp
index 87b0043c..e1a0e8d6 100644
--- a/server/RouteController.cpp
+++ b/server/RouteController.cpp
@@ -92,14 +92,8 @@ struct fib_rule_uid_range {
__u32 end;
};
-const uint16_t NETLINK_REQUEST_FLAGS = NLM_F_REQUEST | NLM_F_ACK;
-const uint16_t NETLINK_CREATE_REQUEST_FLAGS = NETLINK_REQUEST_FLAGS | NLM_F_CREATE | NLM_F_EXCL;
-const uint16_t NETLINK_DUMP_FLAGS = NLM_F_REQUEST | NLM_F_DUMP;
-
const uint8_t AF_FAMILIES[] = {AF_INET, AF_INET6};
-const char* const IP_VERSIONS[] = {"-4", "-6"};
-
const uid_t UID_ROOT = 0;
const char* const IIF_LOOPBACK = "lo";
const char* const IIF_NONE = NULL;
@@ -111,8 +105,6 @@ const bool MODIFY_NON_UID_BASED_RULES = true;
const char* const RT_TABLES_PATH = "/data/misc/net/rt_tables";
const mode_t RT_TABLES_MODE = S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH; // mode 0644, rw-r--r--
-const unsigned ROUTE_FLUSH_ATTEMPTS = 2;
-
// Avoids "non-constant-expression cannot be narrowed from type 'unsigned int' to 'unsigned short'"
// warnings when using RTA_LENGTH(x) inside static initializers (even when x is already uint16_t).
constexpr uint16_t U16_RTA_LENGTH(uint16_t x) {
@@ -311,7 +303,7 @@ WARN_UNUSED_RESULT int modifyIpRule(uint16_t action, uint32_t priority, uint8_t
uint16_t flags = (action == RTM_NEWRULE) ? NETLINK_CREATE_REQUEST_FLAGS : NETLINK_REQUEST_FLAGS;
for (size_t i = 0; i < ARRAY_SIZE(AF_FAMILIES); ++i) {
rule.family = AF_FAMILIES[i];
- if (int ret = sendNetlinkRequest(action, flags, iov, ARRAY_SIZE(iov))) {
+ if (int ret = sendNetlinkRequest(action, flags, iov, ARRAY_SIZE(iov), nullptr)) {
if (!(action == RTM_DELRULE && ret == -ENOENT && priority == RULE_PRIORITY_TETHERING)) {
// Don't log when deleting a tethering rule that's not there. This matches the
// behaviour of clearTetheringRules, which ignores ENOENT in this case.
@@ -423,7 +415,7 @@ WARN_UNUSED_RESULT int modifyIpRoute(uint16_t action, uint32_t table, const char
uint16_t flags = (action == RTM_NEWROUTE) ? NETLINK_CREATE_REQUEST_FLAGS :
NETLINK_REQUEST_FLAGS;
- int ret = sendNetlinkRequest(action, flags, iov, ARRAY_SIZE(iov));
+ int ret = sendNetlinkRequest(action, flags, iov, ARRAY_SIZE(iov), nullptr);
if (ret) {
ALOGE("Error %s route %s -> %s %s to table %u: %s",
actionName(action), destination, nexthop, interface, table, strerror(-ret));
@@ -842,72 +834,6 @@ WARN_UNUSED_RESULT int modifyTetheredNetwork(uint16_t action, const char* inputI
inputInterface, OIF_NONE, INVALID_UID, INVALID_UID);
}
-uint32_t getRulePriority(const nlmsghdr *nlh) {
- uint32_t rta_len = RTM_PAYLOAD(nlh);
- rtmsg *msg = reinterpret_cast<rtmsg *>(NLMSG_DATA(nlh));
- rtattr *rta = reinterpret_cast<rtattr *> RTM_RTA(msg);
- for (; RTA_OK(rta, rta_len); rta = RTA_NEXT(rta, rta_len)) {
- if (rta->rta_type == FRA_PRIORITY) {
- return *(static_cast<uint32_t *>(RTA_DATA(rta)));
- }
- }
- return 0;
-}
-
-// Returns 0 on success or negative errno on failure.
-WARN_UNUSED_RESULT int flushRules() {
- int readSock = openRtNetlinkSocket();
- if (readSock < 0) {
- return readSock;
- }
-
- int writeSock = openRtNetlinkSocket();
- if (writeSock < 0) {
- close(readSock);
- return writeSock;
- }
-
- NetlinkDumpCallback callback = [writeSock] (nlmsghdr *nlh) {
- // Don't touch rules at priority 0 because by default they are used for local input.
- if (getRulePriority(nlh) == 0) return;
-
- nlh->nlmsg_type = RTM_DELRULE;
- nlh->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK;
- if (write(writeSock, nlh, nlh->nlmsg_len) == -1) {
- ALOGE("Error writing flush request: %s", strerror(errno));
- return;
- }
-
- int ret = recvNetlinkAck(writeSock);
- if (ret != 0 && ret != -ENOENT) {
- ALOGW("Flushing rules: %s", strerror(-ret));
- }
- };
-
- int ret = 0;
- for (const int family : { AF_INET, AF_INET6 }) {
- // struct fib_rule_hdr and struct rtmsg are functionally identical.
- rtmsg rule = {
- .rtm_family = static_cast<uint8_t>(family),
- };
- iovec iov[] = {
- { NULL, 0 },
- { &rule, sizeof(rule) },
- };
- uint16_t action = RTM_GETRULE;
- uint16_t flags = NETLINK_DUMP_FLAGS;
-
- if ((ret = sendNetlinkRequest(action, flags, iov, ARRAY_SIZE(iov), callback)) != 0) {
- break;
- }
- }
-
- close(readSock);
- close(writeSock);
-
- return ret;
-}
-
// Adds or removes an IPv4 or IPv6 route to the specified table and, if it's a directly-connected
// route, to the main table as well.
// Returns 0 on success or negative errno on failure.
@@ -945,6 +871,44 @@ WARN_UNUSED_RESULT int modifyRoute(uint16_t action, const char* interface, const
return 0;
}
+WARN_UNUSED_RESULT int clearTetheringRules(const char* inputInterface) {
+ int ret = 0;
+ while (ret == 0) {
+ ret = modifyIpRule(RTM_DELRULE, RULE_PRIORITY_TETHERING, 0, MARK_UNSET, MARK_UNSET,
+ inputInterface, OIF_NONE, INVALID_UID, INVALID_UID);
+ }
+
+ if (ret == -ENOENT) {
+ return 0;
+ } else {
+ return ret;
+ }
+}
+
+uint32_t getRulePriority(const nlmsghdr *nlh) {
+ return getRtmU32Attribute(nlh, FRA_PRIORITY);
+}
+
+uint32_t getRouteTable(const nlmsghdr *nlh) {
+ return getRtmU32Attribute(nlh, RTA_TABLE);
+}
+
+WARN_UNUSED_RESULT int flushRules() {
+ NetlinkDumpFilter shouldDelete = [] (nlmsghdr *nlh) {
+ // Don't touch rules at priority 0 because by default they are used for local input.
+ return getRulePriority(nlh) != 0;
+ };
+ return rtNetlinkFlush(RTM_GETRULE, RTM_DELRULE, "rules", shouldDelete);
+}
+
+WARN_UNUSED_RESULT int flushRoutes(uint32_t table) {
+ NetlinkDumpFilter shouldDelete = [table] (nlmsghdr *nlh) {
+ return getRouteTable(nlh) == table;
+ };
+
+ return rtNetlinkFlush(RTM_GETROUTE, RTM_DELROUTE, "routes", shouldDelete);
+}
+
// Returns 0 on success or negative errno on failure.
WARN_UNUSED_RESULT int flushRoutes(const char* interface) {
uint32_t table = getRouteTableForInterface(interface);
@@ -952,63 +916,17 @@ WARN_UNUSED_RESULT int flushRoutes(const char* interface) {
return -ESRCH;
}
- char tableString[UINT32_STRLEN];
- snprintf(tableString, sizeof(tableString), "%u", table);
-
- int ret = 0;
- for (size_t i = 0; i < ARRAY_SIZE(IP_VERSIONS); ++i) {
- const char* argv[] = {
- IP_PATH,
- IP_VERSIONS[i],
- "route",
- "flush",
- "table",
- tableString,
- };
-
- // A flush works by dumping routes and deleting each route as it's returned, and it can
- // fail if something else deletes the route between the dump and the delete. This can
- // happen, for example, if an interface goes down while we're trying to flush its routes.
- // So try multiple times and only return an error if the last attempt fails.
- //
- // TODO: replace this with our own netlink code.
- unsigned attempts = 0;
- int err;
- do {
- err = android_fork_execvp(ARRAY_SIZE(argv), const_cast<char**>(argv),
- NULL, false, false);
- ++attempts;
- } while (err != 0 && attempts < ROUTE_FLUSH_ATTEMPTS);
- if (err) {
- ALOGE("failed to flush %s routes in table %s after %d attempts",
- IP_VERSIONS[i], tableString, attempts);
- ret = -EREMOTEIO;
- }
- }
+ int ret = flushRoutes(table);
// If we failed to flush routes, the caller may elect to keep this interface around, so keep
// track of its name.
- if (!ret) {
+ if (ret == 0) {
interfaceToTable.erase(interface);
}
return ret;
}
-WARN_UNUSED_RESULT int clearTetheringRules(const char* inputInterface) {
- int ret = 0;
- while (ret == 0) {
- ret = modifyIpRule(RTM_DELRULE, RULE_PRIORITY_TETHERING, 0, MARK_UNSET, MARK_UNSET,
- inputInterface, OIF_NONE, INVALID_UID, INVALID_UID);
- }
-
- if (ret == -ENOENT) {
- return 0;
- } else {
- return ret;
- }
-}
-
} // namespace
int RouteController::Init(unsigned localNetId) {
generated by cgit v1.2.3 (git 2.25.1) at 2025-12-21 16:49:40 +0000