reverse BpfMap & BpfMapRO inheritence to make sense
Bug: 235590615
Bug: 235907076
Bug: 286003437
Test: TreeHugger, m droid gpuservice_unittest libtimeinstate_test bpf_benchmark bpf_module_test libbpf_load_test && mma
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Change-Id: I020a898fe8b257040a100f146654d4a04b19f843
diff --git a/bpf_progs/netd.c b/bpf_progs/netd.c
index 0054d4a..f86d8fd 100644
--- a/bpf_progs/netd.c
+++ b/bpf_progs/netd.c
@@ -89,11 +89,11 @@
DEFINE_BPF_MAP_RW_NETD(cookie_tag_map, HASH, uint64_t, UidTagValue, COOKIE_UID_MAP_SIZE)
DEFINE_BPF_MAP_NO_NETD(uid_counterset_map, HASH, uint32_t, uint8_t, UID_COUNTERSET_MAP_SIZE)
DEFINE_BPF_MAP_NO_NETD(app_uid_stats_map, HASH, uint32_t, StatsValue, APP_STATS_MAP_SIZE)
-DEFINE_BPF_MAP_RW_NETD(stats_map_A, HASH, StatsKey, StatsValue, STATS_MAP_SIZE)
+DEFINE_BPF_MAP_RO_NETD(stats_map_A, HASH, StatsKey, StatsValue, STATS_MAP_SIZE)
DEFINE_BPF_MAP_RO_NETD(stats_map_B, HASH, StatsKey, StatsValue, STATS_MAP_SIZE)
DEFINE_BPF_MAP_NO_NETD(iface_stats_map, HASH, uint32_t, StatsValue, IFACE_STATS_MAP_SIZE)
DEFINE_BPF_MAP_NO_NETD(uid_owner_map, HASH, uint32_t, UidOwnerValue, UID_OWNER_MAP_SIZE)
-DEFINE_BPF_MAP_RW_NETD(uid_permission_map, HASH, uint32_t, uint8_t, UID_OWNER_MAP_SIZE)
+DEFINE_BPF_MAP_RO_NETD(uid_permission_map, HASH, uint32_t, uint8_t, UID_OWNER_MAP_SIZE)
DEFINE_BPF_MAP_NO_NETD(ingress_discard_map, HASH, IngressDiscardKey, IngressDiscardValue,
INGRESS_DISCARD_MAP_SIZE)
diff --git a/netd/BpfHandler.cpp b/netd/BpfHandler.cpp
index fc680d9..fb6d5b8 100644
--- a/netd/BpfHandler.cpp
+++ b/netd/BpfHandler.cpp
@@ -214,7 +214,7 @@
// which might toggle the live stats map and clean it.
const auto countUidStatsEntries = [chargeUid, &totalEntryCount, &perUidEntryCount](
const StatsKey& key,
- const BpfMap<StatsKey, StatsValue>&) {
+ const BpfMapRO<StatsKey, StatsValue>&) {
if (key.uid == chargeUid) {
perUidEntryCount++;
}
@@ -232,9 +232,8 @@
return -EINVAL;
}
- BpfMap<StatsKey, StatsValue>& currentMap =
+ BpfMapRO<StatsKey, StatsValue>& currentMap =
(configuration.value() == SELECT_MAP_A) ? mStatsMapA : mStatsMapB;
- // HACK: mStatsMapB becomes RW BpfMap here, but countUidStatsEntries doesn't modify so it works
base::Result<void> res = currentMap.iterate(countUidStatsEntries);
if (!res.ok()) {
ALOGE("Failed to count the stats entry in map: %s",
diff --git a/netd/BpfHandler.h b/netd/BpfHandler.h
index a6da4eb..9e69efc 100644
--- a/netd/BpfHandler.h
+++ b/netd/BpfHandler.h
@@ -59,10 +59,10 @@
bool hasUpdateDeviceStatsPermission(uid_t uid);
BpfMap<uint64_t, UidTagValue> mCookieTagMap;
- BpfMap<StatsKey, StatsValue> mStatsMapA;
+ BpfMapRO<StatsKey, StatsValue> mStatsMapA;
BpfMapRO<StatsKey, StatsValue> mStatsMapB;
BpfMapRO<uint32_t, uint32_t> mConfigurationMap;
- BpfMap<uint32_t, uint8_t> mUidPermissionMap;
+ BpfMapRO<uint32_t, uint8_t> mUidPermissionMap;
// The limit on the number of stats entries a uid can have in the per uid stats map. BpfHandler
// will block that specific uid from tagging new sockets after the limit is reached.
diff --git a/netd/BpfHandlerTest.cpp b/netd/BpfHandlerTest.cpp
index f5c9a68..b38fa16 100644
--- a/netd/BpfHandlerTest.cpp
+++ b/netd/BpfHandlerTest.cpp
@@ -49,7 +49,7 @@
BpfHandler mBh;
BpfMap<uint64_t, UidTagValue> mFakeCookieTagMap;
BpfMap<StatsKey, StatsValue> mFakeStatsMapA;
- BpfMapRO<uint32_t, uint32_t> mFakeConfigurationMap;
+ BpfMap<uint32_t, uint32_t> mFakeConfigurationMap;
BpfMap<uint32_t, uint8_t> mFakeUidPermissionMap;
void SetUp() {
diff --git a/service-t/native/libs/libnetworkstats/BpfNetworkStats.cpp b/service-t/native/libs/libnetworkstats/BpfNetworkStats.cpp
index fed2979..3101397 100644
--- a/service-t/native/libs/libnetworkstats/BpfNetworkStats.cpp
+++ b/service-t/native/libs/libnetworkstats/BpfNetworkStats.cpp
@@ -41,7 +41,7 @@
using base::Result;
int bpfGetUidStatsInternal(uid_t uid, StatsValue* stats,
- const BpfMap<uint32_t, StatsValue>& appUidStatsMap) {
+ const BpfMapRO<uint32_t, StatsValue>& appUidStatsMap) {
auto statsEntry = appUidStatsMap.readValue(uid);
if (!statsEntry.ok()) {
*stats = {};
@@ -57,14 +57,14 @@
}
int bpfGetIfaceStatsInternal(const char* iface, StatsValue* stats,
- const BpfMap<uint32_t, StatsValue>& ifaceStatsMap,
- const BpfMap<uint32_t, IfaceValue>& ifaceNameMap) {
+ const BpfMapRO<uint32_t, StatsValue>& ifaceStatsMap,
+ const BpfMapRO<uint32_t, IfaceValue>& ifaceNameMap) {
*stats = {};
int64_t unknownIfaceBytesTotal = 0;
const auto processIfaceStats =
[iface, stats, &ifaceNameMap, &unknownIfaceBytesTotal](
const uint32_t& key,
- const BpfMap<uint32_t, StatsValue>& ifaceStatsMap) -> Result<void> {
+ const BpfMapRO<uint32_t, StatsValue>& ifaceStatsMap) -> Result<void> {
char ifname[IFNAMSIZ];
if (getIfaceNameFromMap(ifaceNameMap, ifaceStatsMap, key, ifname, key,
&unknownIfaceBytesTotal)) {
@@ -90,7 +90,7 @@
}
int bpfGetIfIndexStatsInternal(uint32_t ifindex, StatsValue* stats,
- const BpfMap<uint32_t, StatsValue>& ifaceStatsMap) {
+ const BpfMapRO<uint32_t, StatsValue>& ifaceStatsMap) {
auto statsEntry = ifaceStatsMap.readValue(ifindex);
if (!statsEntry.ok()) {
*stats = {};
@@ -120,13 +120,13 @@
}
int parseBpfNetworkStatsDetailInternal(std::vector<stats_line>& lines,
- const BpfMap<StatsKey, StatsValue>& statsMap,
- const BpfMap<uint32_t, IfaceValue>& ifaceMap) {
+ const BpfMapRO<StatsKey, StatsValue>& statsMap,
+ const BpfMapRO<uint32_t, IfaceValue>& ifaceMap) {
int64_t unknownIfaceBytesTotal = 0;
const auto processDetailUidStats =
[&lines, &unknownIfaceBytesTotal, &ifaceMap](
const StatsKey& key,
- const BpfMap<StatsKey, StatsValue>& statsMap) -> Result<void> {
+ const BpfMapRO<StatsKey, StatsValue>& statsMap) -> Result<void> {
char ifname[IFNAMSIZ];
if (getIfaceNameFromMap(ifaceMap, statsMap, key.ifaceIndex, ifname, key,
&unknownIfaceBytesTotal)) {
@@ -212,12 +212,12 @@
}
int parseBpfNetworkStatsDevInternal(std::vector<stats_line>& lines,
- const BpfMap<uint32_t, StatsValue>& statsMap,
- const BpfMap<uint32_t, IfaceValue>& ifaceMap) {
+ const BpfMapRO<uint32_t, StatsValue>& statsMap,
+ const BpfMapRO<uint32_t, IfaceValue>& ifaceMap) {
int64_t unknownIfaceBytesTotal = 0;
const auto processDetailIfaceStats = [&lines, &unknownIfaceBytesTotal, &ifaceMap, &statsMap](
const uint32_t& key, const StatsValue& value,
- const BpfMap<uint32_t, StatsValue>&) {
+ const BpfMapRO<uint32_t, StatsValue>&) {
char ifname[IFNAMSIZ];
if (getIfaceNameFromMap(ifaceMap, statsMap, key, ifname, key, &unknownIfaceBytesTotal)) {
return Result<void>();
diff --git a/service-t/native/libs/libnetworkstats/BpfNetworkStatsTest.cpp b/service-t/native/libs/libnetworkstats/BpfNetworkStatsTest.cpp
index 76c56eb..bcc4550 100644
--- a/service-t/native/libs/libnetworkstats/BpfNetworkStatsTest.cpp
+++ b/service-t/native/libs/libnetworkstats/BpfNetworkStatsTest.cpp
@@ -80,19 +80,19 @@
void SetUp() {
ASSERT_EQ(0, setrlimitForTest());
- mFakeCookieTagMap = BpfMap<uint64_t, UidTagValue>(BPF_MAP_TYPE_HASH, TEST_MAP_SIZE, 0);
+ mFakeCookieTagMap.resetMap(BPF_MAP_TYPE_HASH, TEST_MAP_SIZE);
ASSERT_TRUE(mFakeCookieTagMap.isValid());
- mFakeAppUidStatsMap = BpfMap<uint32_t, StatsValue>(BPF_MAP_TYPE_HASH, TEST_MAP_SIZE, 0);
+ mFakeAppUidStatsMap.resetMap(BPF_MAP_TYPE_HASH, TEST_MAP_SIZE);
ASSERT_TRUE(mFakeAppUidStatsMap.isValid());
- mFakeStatsMap = BpfMap<StatsKey, StatsValue>(BPF_MAP_TYPE_HASH, TEST_MAP_SIZE, 0);
+ mFakeStatsMap.resetMap(BPF_MAP_TYPE_HASH, TEST_MAP_SIZE);
ASSERT_TRUE(mFakeStatsMap.isValid());
- mFakeIfaceIndexNameMap = BpfMap<uint32_t, IfaceValue>(BPF_MAP_TYPE_HASH, TEST_MAP_SIZE, 0);
+ mFakeIfaceIndexNameMap.resetMap(BPF_MAP_TYPE_HASH, TEST_MAP_SIZE);
ASSERT_TRUE(mFakeIfaceIndexNameMap.isValid());
- mFakeIfaceStatsMap = BpfMap<uint32_t, StatsValue>(BPF_MAP_TYPE_HASH, TEST_MAP_SIZE, 0);
+ mFakeIfaceStatsMap.resetMap(BPF_MAP_TYPE_HASH, TEST_MAP_SIZE);
ASSERT_TRUE(mFakeIfaceStatsMap.isValid());
}
diff --git a/service-t/native/libs/libnetworkstats/include/netdbpf/BpfNetworkStats.h b/service-t/native/libs/libnetworkstats/include/netdbpf/BpfNetworkStats.h
index ea068fc..8058d05 100644
--- a/service-t/native/libs/libnetworkstats/include/netdbpf/BpfNetworkStats.h
+++ b/service-t/native/libs/libnetworkstats/include/netdbpf/BpfNetworkStats.h
@@ -57,24 +57,25 @@
// For test only
int bpfGetUidStatsInternal(uid_t uid, StatsValue* stats,
- const BpfMap<uint32_t, StatsValue>& appUidStatsMap);
+ const BpfMapRO<uint32_t, StatsValue>& appUidStatsMap);
// For test only
int bpfGetIfaceStatsInternal(const char* iface, StatsValue* stats,
- const BpfMap<uint32_t, StatsValue>& ifaceStatsMap,
- const BpfMap<uint32_t, IfaceValue>& ifaceNameMap);
+ const BpfMapRO<uint32_t, StatsValue>& ifaceStatsMap,
+ const BpfMapRO<uint32_t, IfaceValue>& ifaceNameMap);
// For test only
int bpfGetIfIndexStatsInternal(uint32_t ifindex, StatsValue* stats,
- const BpfMap<uint32_t, StatsValue>& ifaceStatsMap);
+ const BpfMapRO<uint32_t, StatsValue>& ifaceStatsMap);
// For test only
int parseBpfNetworkStatsDetailInternal(std::vector<stats_line>& lines,
- const BpfMap<StatsKey, StatsValue>& statsMap,
- const BpfMap<uint32_t, IfaceValue>& ifaceMap);
+ const BpfMapRO<StatsKey, StatsValue>& statsMap,
+ const BpfMapRO<uint32_t, IfaceValue>& ifaceMap);
// For test only
int cleanStatsMapInternal(const base::unique_fd& cookieTagMap, const base::unique_fd& tagStatsMap);
// For test only
template <class Key>
-int getIfaceNameFromMap(const BpfMap<uint32_t, IfaceValue>& ifaceMap,
- const BpfMap<Key, StatsValue>& statsMap, uint32_t ifaceIndex, char* ifname,
+int getIfaceNameFromMap(const BpfMapRO<uint32_t, IfaceValue>& ifaceMap,
+ const BpfMapRO<Key, StatsValue>& statsMap,
+ uint32_t ifaceIndex, char* ifname,
const Key& curKey, int64_t* unknownIfaceBytesTotal) {
auto iface = ifaceMap.readValue(ifaceIndex);
if (!iface.ok()) {
@@ -86,7 +87,7 @@
}
template <class Key>
-void maybeLogUnknownIface(int ifaceIndex, const BpfMap<Key, StatsValue>& statsMap,
+void maybeLogUnknownIface(int ifaceIndex, const BpfMapRO<Key, StatsValue>& statsMap,
const Key& curKey, int64_t* unknownIfaceBytesTotal) {
// Have we already logged an error?
if (*unknownIfaceBytesTotal == -1) {
@@ -110,8 +111,8 @@
// For test only
int parseBpfNetworkStatsDevInternal(std::vector<stats_line>& lines,
- const BpfMap<uint32_t, StatsValue>& statsMap,
- const BpfMap<uint32_t, IfaceValue>& ifaceMap);
+ const BpfMapRO<uint32_t, StatsValue>& statsMap,
+ const BpfMapRO<uint32_t, IfaceValue>& ifaceMap);
int bpfGetUidStats(uid_t uid, StatsValue* stats);
int bpfGetIfaceStats(const char* iface, StatsValue* stats);
diff --git a/staticlibs/native/bpf_headers/BpfMapTest.cpp b/staticlibs/native/bpf_headers/BpfMapTest.cpp
index 10afe86..862114d 100644
--- a/staticlibs/native/bpf_headers/BpfMapTest.cpp
+++ b/staticlibs/native/bpf_headers/BpfMapTest.cpp
@@ -107,12 +107,14 @@
BpfMap<uint32_t, uint32_t> testMap1;
checkMapInvalid(testMap1);
- BpfMap<uint32_t, uint32_t> testMap2(BPF_MAP_TYPE_HASH, TEST_MAP_SIZE, BPF_F_NO_PREALLOC);
+ BpfMap<uint32_t, uint32_t> testMap2;
+ ASSERT_RESULT_OK(testMap2.resetMap(BPF_MAP_TYPE_HASH, TEST_MAP_SIZE, BPF_F_NO_PREALLOC));
checkMapValid(testMap2);
}
TEST_F(BpfMapTest, basicHelpers) {
- BpfMap<uint32_t, uint32_t> testMap(BPF_MAP_TYPE_HASH, TEST_MAP_SIZE, BPF_F_NO_PREALLOC);
+ BpfMap<uint32_t, uint32_t> testMap;
+ ASSERT_RESULT_OK(testMap.resetMap(BPF_MAP_TYPE_HASH, TEST_MAP_SIZE, BPF_F_NO_PREALLOC));
uint32_t key = TEST_KEY1;
uint32_t value_write = TEST_VALUE1;
writeToMapAndCheck(testMap, key, value_write);
@@ -126,7 +128,8 @@
}
TEST_F(BpfMapTest, reset) {
- BpfMap<uint32_t, uint32_t> testMap(BPF_MAP_TYPE_HASH, TEST_MAP_SIZE, BPF_F_NO_PREALLOC);
+ BpfMap<uint32_t, uint32_t> testMap;
+ ASSERT_RESULT_OK(testMap.resetMap(BPF_MAP_TYPE_HASH, TEST_MAP_SIZE, BPF_F_NO_PREALLOC));
uint32_t key = TEST_KEY1;
uint32_t value_write = TEST_VALUE1;
writeToMapAndCheck(testMap, key, value_write);
@@ -138,7 +141,8 @@
}
TEST_F(BpfMapTest, moveConstructor) {
- BpfMap<uint32_t, uint32_t> testMap1(BPF_MAP_TYPE_HASH, TEST_MAP_SIZE, BPF_F_NO_PREALLOC);
+ BpfMap<uint32_t, uint32_t> testMap1;
+ ASSERT_RESULT_OK(testMap1.resetMap(BPF_MAP_TYPE_HASH, TEST_MAP_SIZE, BPF_F_NO_PREALLOC));
BpfMap<uint32_t, uint32_t> testMap2;
testMap2 = std::move(testMap1);
uint32_t key = TEST_KEY1;
@@ -149,7 +153,8 @@
TEST_F(BpfMapTest, SetUpMap) {
EXPECT_NE(0, access(PINNED_MAP_PATH, R_OK));
- BpfMap<uint32_t, uint32_t> testMap1(BPF_MAP_TYPE_HASH, TEST_MAP_SIZE, BPF_F_NO_PREALLOC);
+ BpfMap<uint32_t, uint32_t> testMap1;
+ ASSERT_RESULT_OK(testMap1.resetMap(BPF_MAP_TYPE_HASH, TEST_MAP_SIZE, BPF_F_NO_PREALLOC));
ASSERT_EQ(0, bpfFdPin(testMap1.getMap(), PINNED_MAP_PATH));
EXPECT_EQ(0, access(PINNED_MAP_PATH, R_OK));
checkMapValid(testMap1);
@@ -164,7 +169,8 @@
}
TEST_F(BpfMapTest, iterate) {
- BpfMap<uint32_t, uint32_t> testMap(BPF_MAP_TYPE_HASH, TEST_MAP_SIZE, BPF_F_NO_PREALLOC);
+ BpfMap<uint32_t, uint32_t> testMap;
+ ASSERT_RESULT_OK(testMap.resetMap(BPF_MAP_TYPE_HASH, TEST_MAP_SIZE, BPF_F_NO_PREALLOC));
populateMap(TEST_MAP_SIZE, testMap);
int totalCount = 0;
int totalSum = 0;
@@ -182,7 +188,8 @@
}
TEST_F(BpfMapTest, iterateWithValue) {
- BpfMap<uint32_t, uint32_t> testMap(BPF_MAP_TYPE_HASH, TEST_MAP_SIZE, BPF_F_NO_PREALLOC);
+ BpfMap<uint32_t, uint32_t> testMap;
+ ASSERT_RESULT_OK(testMap.resetMap(BPF_MAP_TYPE_HASH, TEST_MAP_SIZE, BPF_F_NO_PREALLOC));
populateMap(TEST_MAP_SIZE, testMap);
int totalCount = 0;
int totalSum = 0;
@@ -202,7 +209,8 @@
}
TEST_F(BpfMapTest, mapIsEmpty) {
- BpfMap<uint32_t, uint32_t> testMap(BPF_MAP_TYPE_HASH, TEST_MAP_SIZE, BPF_F_NO_PREALLOC);
+ BpfMap<uint32_t, uint32_t> testMap;
+ ASSERT_RESULT_OK(testMap.resetMap(BPF_MAP_TYPE_HASH, TEST_MAP_SIZE, BPF_F_NO_PREALLOC));
expectMapEmpty(testMap);
uint32_t key = TEST_KEY1;
uint32_t value_write = TEST_VALUE1;
@@ -232,7 +240,8 @@
}
TEST_F(BpfMapTest, mapClear) {
- BpfMap<uint32_t, uint32_t> testMap(BPF_MAP_TYPE_HASH, TEST_MAP_SIZE, BPF_F_NO_PREALLOC);
+ BpfMap<uint32_t, uint32_t> testMap;
+ ASSERT_RESULT_OK(testMap.resetMap(BPF_MAP_TYPE_HASH, TEST_MAP_SIZE));
populateMap(TEST_MAP_SIZE, testMap);
Result<bool> isEmpty = testMap.isEmpty();
ASSERT_RESULT_OK(isEmpty);
diff --git a/staticlibs/native/bpf_headers/include/bpf/BpfMap.h b/staticlibs/native/bpf_headers/include/bpf/BpfMap.h
index 3be7067..5d7eb0d 100644
--- a/staticlibs/native/bpf_headers/include/bpf/BpfMap.h
+++ b/staticlibs/native/bpf_headers/include/bpf/BpfMap.h
@@ -48,41 +48,32 @@
// is not safe to iterate over a map while another thread or process is deleting
// from it. In this case the iteration can return duplicate entries.
template <class Key, class Value>
-class BpfMap {
+class BpfMapRO {
public:
- BpfMap<Key, Value>() {};
+ BpfMapRO<Key, Value>() {};
// explicitly force no copy constructor, since it would need to dup the fd
// (later on, for testing, we still make available a copy assignment operator)
- BpfMap<Key, Value>(const BpfMap<Key, Value>&) = delete;
+ BpfMapRO<Key, Value>(const BpfMapRO<Key, Value>&) = delete;
- private:
- void abortOnKeyOrValueSizeMismatch() {
+ protected:
+ void abortOnMismatch(bool writable) const {
if (!mMapFd.ok()) abort();
if (isAtLeastKernelVersion(4, 14, 0)) {
+ int flags = bpfGetFdMapFlags(mMapFd);
+ if (flags < 0) abort();
+ if (flags & BPF_F_WRONLY) abort();
+ if (writable && (flags & BPF_F_RDONLY)) abort();
if (bpfGetFdKeySize(mMapFd) != sizeof(Key)) abort();
if (bpfGetFdValueSize(mMapFd) != sizeof(Value)) abort();
}
}
- protected:
- // flag must be within BPF_OBJ_FLAG_MASK, ie. 0, BPF_F_RDONLY, BPF_F_WRONLY
- BpfMap<Key, Value>(const char* pathname, uint32_t flags) {
- mMapFd.reset(mapRetrieve(pathname, flags));
- abortOnKeyOrValueSizeMismatch();
- }
-
public:
- explicit BpfMap<Key, Value>(const char* pathname) : BpfMap<Key, Value>(pathname, 0) {}
-
-#ifdef BPF_MAP_MAKE_VISIBLE_FOR_TESTING
- // All bpf maps should be created by the bpfloader, so this constructor
- // is reserved for tests
- BpfMap<Key, Value>(bpf_map_type map_type, uint32_t max_entries, uint32_t map_flags = 0) {
- mMapFd.reset(createMap(map_type, sizeof(Key), sizeof(Value), max_entries, map_flags));
- if (!mMapFd.ok()) abort();
+ explicit BpfMapRO<Key, Value>(const char* pathname) {
+ mMapFd.reset(mapRetrieveRO(pathname));
+ abortOnMismatch(/* writable */ false);
}
-#endif
Result<Key> getFirstKey() const {
Key firstKey;
@@ -100,13 +91,6 @@
return nextKey;
}
- Result<void> writeValue(const Key& key, const Value& value, uint64_t flags) {
- if (writeToMapEntry(mMapFd, &key, &value, flags)) {
- return ErrnoErrorf("Write to map {} failed", mMapFd.get());
- }
- return {};
- }
-
Result<Value> readValue(const Key key) const {
Value value;
if (findMapEntry(mMapFd, &key, &value)) {
@@ -115,6 +99,155 @@
return value;
}
+ protected:
+ [[clang::reinitializes]] Result<void> init(const char* path, int fd, bool writable) {
+ mMapFd.reset(fd);
+ if (!mMapFd.ok()) {
+ return ErrnoErrorf("Pinned map not accessible or does not exist: ({})", path);
+ }
+ // Normally we should return an error here instead of calling abort,
+ // but this cannot happen at runtime without a massive code bug (K/V type mismatch)
+ // and as such it's better to just blow the system up and let the developer fix it.
+ // Crashes are much more likely to be noticed than logs and missing functionality.
+ abortOnMismatch(writable);
+ return {};
+ }
+
+ public:
+ // Function that tries to get map from a pinned path.
+ [[clang::reinitializes]] Result<void> init(const char* path) {
+ return init(path, mapRetrieveRO(path), /* writable */ false);
+ }
+
+ // Iterate through the map and handle each key retrieved based on the filter
+ // without modification of map content.
+ Result<void> iterate(
+ const function<Result<void>(const Key& key,
+ const BpfMapRO<Key, Value>& map)>& filter) const;
+
+ // Iterate through the map and get each <key, value> pair, handle each <key,
+ // value> pair based on the filter without modification of map content.
+ Result<void> iterateWithValue(
+ const function<Result<void>(const Key& key, const Value& value,
+ const BpfMapRO<Key, Value>& map)>& filter) const;
+
+#ifdef BPF_MAP_MAKE_VISIBLE_FOR_TESTING
+ const unique_fd& getMap() const { return mMapFd; };
+
+ // Copy assignment operator - due to need for fd duping, should not be used in non-test code.
+ BpfMapRO<Key, Value>& operator=(const BpfMapRO<Key, Value>& other) {
+ if (this != &other) mMapFd.reset(fcntl(other.mMapFd.get(), F_DUPFD_CLOEXEC, 0));
+ return *this;
+ }
+#else
+ BpfMapRO<Key, Value>& operator=(const BpfMapRO<Key, Value>&) = delete;
+#endif
+
+ // Move assignment operator
+ BpfMapRO<Key, Value>& operator=(BpfMapRO<Key, Value>&& other) noexcept {
+ if (this != &other) {
+ mMapFd = std::move(other.mMapFd);
+ other.reset();
+ }
+ return *this;
+ }
+
+#ifdef BPF_MAP_MAKE_VISIBLE_FOR_TESTING
+ // Note that unique_fd.reset() carefully saves and restores the errno,
+ // and BpfMap.reset() won't touch the errno if passed in fd is negative either,
+ // hence you can do something like BpfMap.reset(systemcall()) and then
+ // check BpfMap.isValid() and look at errno and see why systemcall() failed.
+ [[clang::reinitializes]] void reset(int fd) {
+ mMapFd.reset(fd);
+ if (mMapFd.ok()) abortOnMismatch(/* writable */ false); // false isn't ideal
+ }
+
+ // unique_fd has an implicit int conversion defined, which combined with the above
+ // reset(int) would result in double ownership of the fd, hence we either need a custom
+ // implementation of reset(unique_fd), or to delete it and thus cause compile failures
+ // to catch this and prevent it.
+ void reset(unique_fd fd) = delete;
+#endif
+
+ [[clang::reinitializes]] void reset() {
+ mMapFd.reset();
+ }
+
+ bool isValid() const { return mMapFd.ok(); }
+
+ Result<bool> isEmpty() const {
+ auto key = getFirstKey();
+ if (key.ok()) return false;
+ if (key.error().code() == ENOENT) return true;
+ return key.error();
+ }
+
+ protected:
+ unique_fd mMapFd;
+};
+
+template <class Key, class Value>
+Result<void> BpfMapRO<Key, Value>::iterate(
+ const function<Result<void>(const Key& key,
+ const BpfMapRO<Key, Value>& map)>& filter) const {
+ Result<Key> curKey = getFirstKey();
+ while (curKey.ok()) {
+ const Result<Key>& nextKey = getNextKey(curKey.value());
+ Result<void> status = filter(curKey.value(), *this);
+ if (!status.ok()) return status;
+ curKey = nextKey;
+ }
+ if (curKey.error().code() == ENOENT) return {};
+ return curKey.error();
+}
+
+template <class Key, class Value>
+Result<void> BpfMapRO<Key, Value>::iterateWithValue(
+ const function<Result<void>(const Key& key, const Value& value,
+ const BpfMapRO<Key, Value>& map)>& filter) const {
+ Result<Key> curKey = getFirstKey();
+ while (curKey.ok()) {
+ const Result<Key>& nextKey = getNextKey(curKey.value());
+ Result<Value> curValue = readValue(curKey.value());
+ if (!curValue.ok()) return curValue.error();
+ Result<void> status = filter(curKey.value(), curValue.value(), *this);
+ if (!status.ok()) return status;
+ curKey = nextKey;
+ }
+ if (curKey.error().code() == ENOENT) return {};
+ return curKey.error();
+}
+
+template <class Key, class Value>
+class BpfMap : public BpfMapRO<Key, Value> {
+ protected:
+ using BpfMapRO<Key, Value>::mMapFd;
+ using BpfMapRO<Key, Value>::abortOnMismatch;
+
+ public:
+ using BpfMapRO<Key, Value>::getFirstKey;
+ using BpfMapRO<Key, Value>::getNextKey;
+ using BpfMapRO<Key, Value>::readValue;
+
+ BpfMap<Key, Value>() {};
+
+ explicit BpfMap<Key, Value>(const char* pathname) {
+ mMapFd.reset(mapRetrieveRW(pathname));
+ abortOnMismatch(/* writable */ true);
+ }
+
+ // Function that tries to get map from a pinned path.
+ [[clang::reinitializes]] Result<void> init(const char* path) {
+ return BpfMapRO<Key,Value>::init(path, mapRetrieveRW(path), /* writable */ true);
+ }
+
+ Result<void> writeValue(const Key& key, const Value& value, uint64_t flags) {
+ if (writeToMapEntry(mMapFd, &key, &value, flags)) {
+ return ErrnoErrorf("Write to map {} failed", mMapFd.get());
+ }
+ return {};
+ }
+
Result<void> deleteValue(const Key& key) {
if (deleteMapEntry(mMapFd, &key)) {
return ErrnoErrorf("Delete entry from map {} failed", mMapFd.get());
@@ -122,37 +255,33 @@
return {};
}
- protected:
- [[clang::reinitializes]] Result<void> init(const char* path, int fd) {
- mMapFd.reset(fd);
- if (!mMapFd.ok()) {
- return ErrnoErrorf("Pinned map not accessible or does not exist: ({})", path);
+ Result<void> clear() {
+ while (true) {
+ auto key = getFirstKey();
+ if (!key.ok()) {
+ if (key.error().code() == ENOENT) return {}; // empty: success
+ return key.error(); // Anything else is an error
+ }
+ auto res = deleteValue(key.value());
+ if (!res.ok()) {
+ // Someone else could have deleted the key, so ignore ENOENT
+ if (res.error().code() == ENOENT) continue;
+ ALOGE("Failed to delete data %s", strerror(res.error().code()));
+ return res.error();
+ }
}
- // Normally we should return an error here instead of calling abort,
- // but this cannot happen at runtime without a massive code bug (K/V type mismatch)
- // and as such it's better to just blow the system up and let the developer fix it.
- // Crashes are much more likely to be noticed than logs and missing functionality.
- abortOnKeyOrValueSizeMismatch();
- return {};
}
- public:
- // Function that tries to get map from a pinned path.
- [[clang::reinitializes]] Result<void> init(const char* path) {
- return init(path, mapRetrieveRW(path));
- }
-
-
#ifdef BPF_MAP_MAKE_VISIBLE_FOR_TESTING
- // due to Android SELinux limitations which prevent map creation by anyone besides the bpfloader
- // this should only ever be used by test code, it is equivalent to:
- // .reset(createMap(type, keysize, valuesize, max_entries, map_flags)
- // TODO: derive map_flags from BpfMap vs BpfMapRO
[[clang::reinitializes]] Result<void> resetMap(bpf_map_type map_type,
- uint32_t max_entries,
- uint32_t map_flags = 0) {
- mMapFd.reset(createMap(map_type, sizeof(Key), sizeof(Value), max_entries, map_flags));
+ uint32_t max_entries,
+ uint32_t map_flags = 0) {
+ if (map_flags & BPF_F_WRONLY) abort();
+ if (map_flags & BPF_F_RDONLY) abort();
+ mMapFd.reset(createMap(map_type, sizeof(Key), sizeof(Value), max_entries,
+ map_flags));
if (!mMapFd.ok()) return ErrnoErrorf("Unable to create map.");
+ abortOnMismatch(/* writable */ true);
return {};
}
#endif
@@ -180,72 +309,6 @@
const function<Result<void>(const Key& key, const Value& value,
BpfMap<Key, Value>& map)>& filter);
-#ifdef BPF_MAP_MAKE_VISIBLE_FOR_TESTING
- const unique_fd& getMap() const { return mMapFd; };
-
- // Copy assignment operator - due to need for fd duping, should not be used in non-test code.
- BpfMap<Key, Value>& operator=(const BpfMap<Key, Value>& other) {
- if (this != &other) mMapFd.reset(fcntl(other.mMapFd.get(), F_DUPFD_CLOEXEC, 0));
- return *this;
- }
-#else
- BpfMap<Key, Value>& operator=(const BpfMap<Key, Value>&) = delete;
-#endif
-
- // Move assignment operator
- BpfMap<Key, Value>& operator=(BpfMap<Key, Value>&& other) noexcept {
- if (this != &other) {
- mMapFd = std::move(other.mMapFd);
- other.reset();
- }
- return *this;
- }
-
- void reset(unique_fd fd) = delete;
-
-#ifdef BPF_MAP_MAKE_VISIBLE_FOR_TESTING
- // Note that unique_fd.reset() carefully saves and restores the errno,
- // and BpfMap.reset() won't touch the errno if passed in fd is negative either,
- // hence you can do something like BpfMap.reset(systemcall()) and then
- // check BpfMap.isValid() and look at errno and see why systemcall() failed.
- [[clang::reinitializes]] void reset(int fd) {
- mMapFd.reset(fd);
- if (mMapFd.ok()) abortOnKeyOrValueSizeMismatch();
- }
-#endif
-
- [[clang::reinitializes]] void reset() {
- mMapFd.reset();
- }
-
- bool isValid() const { return mMapFd.ok(); }
-
- Result<void> clear() {
- while (true) {
- auto key = getFirstKey();
- if (!key.ok()) {
- if (key.error().code() == ENOENT) return {}; // empty: success
- return key.error(); // Anything else is an error
- }
- auto res = deleteValue(key.value());
- if (!res.ok()) {
- // Someone else could have deleted the key, so ignore ENOENT
- if (res.error().code() == ENOENT) continue;
- ALOGE("Failed to delete data %s", strerror(res.error().code()));
- return res.error();
- }
- }
- }
-
- Result<bool> isEmpty() const {
- auto key = getFirstKey();
- if (key.ok()) return false;
- if (key.error().code() == ENOENT) return true;
- return key.error();
- }
-
- private:
- unique_fd mMapFd;
};
template <class Key, class Value>
@@ -312,19 +375,5 @@
return curKey.error();
}
-template <class Key, class Value>
-class BpfMapRO : public BpfMap<Key, Value> {
- public:
- BpfMapRO<Key, Value>() {};
-
- explicit BpfMapRO<Key, Value>(const char* pathname)
- : BpfMap<Key, Value>(pathname, BPF_F_RDONLY) {}
-
- // Function that tries to get map from a pinned path.
- [[clang::reinitializes]] Result<void> init(const char* path) {
- return BpfMap<Key,Value>::init(path, mapRetrieveRO(path));
- }
-};
-
} // namespace bpf
} // namespace android