Merge "libbinder: remove per-binder wire protocol version"
diff --git a/libs/binder/BpBinder.cpp b/libs/binder/BpBinder.cpp
index 3099296..765e21c 100644
--- a/libs/binder/BpBinder.cpp
+++ b/libs/binder/BpBinder.cpp
@@ -261,15 +261,15 @@
if (code >= FIRST_CALL_TRANSACTION && code <= LAST_CALL_TRANSACTION) {
using android::internal::Stability;
- auto category = Stability::getCategory(this);
+ int16_t stability = Stability::getRepr(this);
Stability::Level required = privateVendor ? Stability::VENDOR
: Stability::getLocalLevel();
- if (CC_UNLIKELY(!Stability::check(category, required))) {
+ if (CC_UNLIKELY(!Stability::check(stability, required))) {
ALOGE("Cannot do a user transaction on a %s binder (%s) in a %s context.",
- category.debugString().c_str(),
- String8(getInterfaceDescriptor()).c_str(),
- Stability::levelString(required).c_str());
+ Stability::levelString(stability).c_str(),
+ String8(getInterfaceDescriptor()).c_str(),
+ Stability::levelString(required).c_str());
return BAD_TYPE;
}
}
diff --git a/libs/binder/Parcel.cpp b/libs/binder/Parcel.cpp
index ebba375..956524a 100644
--- a/libs/binder/Parcel.cpp
+++ b/libs/binder/Parcel.cpp
@@ -173,7 +173,7 @@
status_t Parcel::finishFlattenBinder(const sp<IBinder>& binder)
{
internal::Stability::tryMarkCompilationUnit(binder.get());
- int16_t rep = internal::Stability::getCategory(binder.get()).repr();
+ int16_t rep = internal::Stability::getRepr(binder.get());
return writeInt32(rep);
}
diff --git a/libs/binder/Stability.cpp b/libs/binder/Stability.cpp
index dac3819..d25c038 100644
--- a/libs/binder/Stability.cpp
+++ b/libs/binder/Stability.cpp
@@ -23,20 +23,6 @@
namespace android {
namespace internal {
-// the libbinder parcel format is currently unstable
-
-// oldest version which is supported
-constexpr uint8_t kBinderWireFormatOldest = 1;
-// current version
-constexpr uint8_t kBinderWireFormatVersion = 1;
-
-Stability::Category Stability::Category::currentFromLevel(Level level) {
- return {
- .version = kBinderWireFormatVersion,
- .level = level,
- };
-}
-
void Stability::forceDowngradeToStability(const sp<IBinder>& binder, Level level) {
// Downgrading a remote binder would require also copying the version from
// the binder sent here. In practice though, we don't need to downgrade the
@@ -44,8 +30,7 @@
// what we can do to it.
LOG_ALWAYS_FATAL_IF(!binder || !binder->localBinder(), "Can only downgrade local binder");
- auto stability = Category::currentFromLevel(level);
- status_t result = setRepr(binder.get(), stability.repr(), REPR_LOG | REPR_ALLOW_DOWNGRADE);
+ status_t result = setRepr(binder.get(), level, REPR_LOG | REPR_ALLOW_DOWNGRADE);
LOG_ALWAYS_FATAL_IF(result != OK, "Should only mark known object.");
}
@@ -61,41 +46,31 @@
forceDowngradeToStability(binder, Level::VENDOR);
}
-std::string Stability::Category::debugString() {
- return levelString(level) + " wire protocol version "
- + std::to_string(version);
-}
-
void Stability::markCompilationUnit(IBinder* binder) {
- auto stability = Category::currentFromLevel(getLocalLevel());
- status_t result = setRepr(binder, stability.repr(), REPR_LOG);
+ status_t result = setRepr(binder, getLocalLevel(), REPR_LOG);
LOG_ALWAYS_FATAL_IF(result != OK, "Should only mark known object.");
}
void Stability::markVintf(IBinder* binder) {
- auto stability = Category::currentFromLevel(Level::VINTF);
- status_t result = setRepr(binder, stability.repr(), REPR_LOG);
+ status_t result = setRepr(binder, Level::VINTF, REPR_LOG);
LOG_ALWAYS_FATAL_IF(result != OK, "Should only mark known object.");
}
std::string Stability::debugToString(const sp<IBinder>& binder) {
- auto stability = getCategory(binder.get());
- return stability.debugString();
+ return levelString(getRepr(binder.get()));
}
void Stability::markVndk(IBinder* binder) {
- auto stability = Category::currentFromLevel(Level::VENDOR);
- status_t result = setRepr(binder, stability.repr(), REPR_LOG);
+ status_t result = setRepr(binder, Level::VENDOR, REPR_LOG);
LOG_ALWAYS_FATAL_IF(result != OK, "Should only mark known object.");
}
bool Stability::requiresVintfDeclaration(const sp<IBinder>& binder) {
- return check(getCategory(binder.get()), Level::VINTF);
+ return check(getRepr(binder.get()), Level::VINTF);
}
void Stability::tryMarkCompilationUnit(IBinder* binder) {
- auto stability = Category::currentFromLevel(getLocalLevel());
- (void) setRepr(binder, stability.repr(), REPR_NONE);
+ (void)setRepr(binder, getLocalLevel(), REPR_NONE);
}
Stability::Level Stability::getLocalLevel() {
@@ -117,92 +92,77 @@
#endif
}
-status_t Stability::setRepr(IBinder* binder, int32_t representation, uint32_t flags) {
+status_t Stability::setRepr(IBinder* binder, int32_t setting, uint32_t flags) {
bool log = flags & REPR_LOG;
bool allowDowngrade = flags & REPR_ALLOW_DOWNGRADE;
- auto current = getCategory(binder);
- auto setting = Category::fromRepr(representation);
-
- // If we have ahold of a binder with a newer declared version, then it
- // should support older versions, and we will simply write our parcels with
- // the current wire parcel format.
- if (setting.version < kBinderWireFormatOldest) {
- // always log, because this shouldn't happen
- ALOGE("Cannot accept binder with older binder wire protocol version "
- "%u. Versions less than %u are unsupported.", setting.version,
- kBinderWireFormatOldest);
- return BAD_TYPE;
- }
+ int16_t current = getRepr(binder);
// null binder is always written w/ 'UNDECLARED' stability
if (binder == nullptr) {
- if (setting.level == UNDECLARED) {
+ if (setting == UNDECLARED) {
return OK;
} else {
if (log) {
- ALOGE("Null binder written with stability %s.",
- levelString(setting.level).c_str());
+ ALOGE("Null binder written with stability %s.", levelString(setting).c_str());
}
return BAD_TYPE;
}
}
- if (!isDeclaredLevel(setting.level)) {
+ if (!isDeclaredLevel(setting)) {
if (log) {
- ALOGE("Can only set known stability, not %u.", setting.level);
+ ALOGE("Can only set known stability, not %d.", setting);
}
return BAD_TYPE;
}
+ Level levelSetting = static_cast<Level>(setting);
if (current == setting) return OK;
- bool hasAlreadyBeenSet = current.repr() != 0;
- bool isAllowedDowngrade = allowDowngrade && check(current, setting.level);
+ bool hasAlreadyBeenSet = current != Level::UNDECLARED;
+ bool isAllowedDowngrade = allowDowngrade && check(current, levelSetting);
if (hasAlreadyBeenSet && !isAllowedDowngrade) {
if (log) {
ALOGE("Interface being set with %s but it is already marked as %s",
- setting.debugString().c_str(),
- current.debugString().c_str());
+ levelString(setting).c_str(), levelString(current).c_str());
}
return BAD_TYPE;
}
if (isAllowedDowngrade) {
- ALOGI("Interface set with %s downgraded to %s stability",
- current.debugString().c_str(),
- setting.debugString().c_str());
+ ALOGI("Interface set with %s downgraded to %s stability", levelString(current).c_str(),
+ levelString(setting).c_str());
}
BBinder* local = binder->localBinder();
if (local != nullptr) {
- local->mStability = setting.repr();
+ local->mStability = setting;
} else {
- binder->remoteBinder()->mStability = setting.repr();
+ binder->remoteBinder()->mStability = setting;
}
return OK;
}
-Stability::Category Stability::getCategory(IBinder* binder) {
+int16_t Stability::getRepr(IBinder* binder) {
if (binder == nullptr) {
- return Category::currentFromLevel(Level::UNDECLARED);
+ return Level::UNDECLARED;
}
BBinder* local = binder->localBinder();
if (local != nullptr) {
- return Category::fromRepr(local->mStability);
+ return local->mStability;
}
- return Category::fromRepr(binder->remoteBinder()->mStability);
+ return binder->remoteBinder()->mStability;
}
-bool Stability::check(Category provided, Level required) {
- bool stable = (provided.level & required) == required;
+bool Stability::check(int16_t provided, Level required) {
+ bool stable = (provided & required) == required;
- if (provided.level != UNDECLARED && !isDeclaredLevel(provided.level)) {
- ALOGE("Unknown stability when checking interface stability %d.",
- provided.level);
+ if (provided != UNDECLARED && !isDeclaredLevel(provided)) {
+ ALOGE("Unknown stability when checking interface stability %d.", provided);
stable = false;
}
@@ -210,11 +170,11 @@
return stable;
}
-bool Stability::isDeclaredLevel(Level stability) {
+bool Stability::isDeclaredLevel(int32_t stability) {
return stability == VENDOR || stability == SYSTEM || stability == VINTF;
}
-std::string Stability::levelString(Level level) {
+std::string Stability::levelString(int32_t level) {
switch (level) {
case Level::UNDECLARED: return "undeclared stability";
case Level::VENDOR: return "vendor stability";
diff --git a/libs/binder/include/binder/Stability.h b/libs/binder/include/binder/Stability.h
index 629b565..ce4362f 100644
--- a/libs/binder/include/binder/Stability.h
+++ b/libs/binder/include/binder/Stability.h
@@ -44,10 +44,9 @@
// to old servers, and new servers know how to interpret the 8-byte result,
// they can still communicate.
//
-// Every binder object has a stability level associated with it, and when
-// communicating with a binder, we make sure that the command we sent is one
-// that it knows how to process. The summary of stability of a binder is
-// represented by a Stability::Category object.
+// This class is specifically about (1). (2) is not currently tracked by
+// libbinder for regular binder calls, and everything on the system uses the
+// same copy of libbinder.
class Stability final {
public:
@@ -128,7 +127,10 @@
static void tryMarkCompilationUnit(IBinder* binder);
- enum Level : uint8_t {
+ // Currently, we use int16_t for Level so that it can fit in BBinder.
+ // However, on the wire, we have 4 bytes reserved for stability, so whenever
+ // we ingest a Level, we always accept an int32_t.
+ enum Level : int16_t {
UNDECLARED = 0,
VENDOR = 0b000011,
@@ -136,37 +138,6 @@
VINTF = 0b111111,
};
- // This is the format of stability passed on the wire. It is only 2 bytes
- // long, but 2 bytes in addition to this are reserved here. The difference
- // in size is in order to free up space in BBinder, which is fixed by
- // prebuilts inheriting from it.
- struct Category {
- static inline Category fromRepr(int16_t representation) {
- return *reinterpret_cast<Category*>(&representation);
- }
- int16_t repr() const { return *reinterpret_cast<const int16_t*>(this); }
- static inline Category currentFromLevel(Level level);
-
- bool operator== (const Category& o) const {
- return repr() == o.repr();
- }
- bool operator!= (const Category& o) const {
- return !(*this == o);
- }
-
- std::string debugString();
-
- // This is the version of the wire protocol associated with the host
- // process of a particular binder. As the wire protocol changes, if
- // sending a transaction to a binder with an old version, the Parcel
- // class must write parcels according to the version documented here.
- uint8_t version;
-
- // bitmask of Stability::Level
- Level level;
- };
- static_assert(sizeof(Category) == sizeof(int16_t));
-
// returns the stability according to how this was built
static Level getLocalLevel();
@@ -179,18 +150,18 @@
REPR_ALLOW_DOWNGRADE = 2,
};
// applies stability to binder if stability level is known
- __attribute__((warn_unused_result))
- static status_t setRepr(IBinder* binder, int32_t representation, uint32_t flags);
+ __attribute__((warn_unused_result)) static status_t setRepr(IBinder* binder, int32_t setting,
+ uint32_t flags);
// get stability information as encoded on the wire
- static Category getCategory(IBinder* binder);
+ static int16_t getRepr(IBinder* binder);
// whether a transaction on binder is allowed, if the transaction
// is done from a context with a specific stability level
- static bool check(Category provided, Level required);
+ static bool check(int16_t provided, Level required);
- static bool isDeclaredLevel(Level level);
- static std::string levelString(Level level);
+ static bool isDeclaredLevel(int32_t level);
+ static std::string levelString(int32_t level);
Stability();
};