Add build fingerprint and ensure match on .so load

bug 19216507

If ro.debuggable system property is set,
- Compute the Adler32 checksum of bitcode, compiler arguments, bcc,
  libclcore files.
- On shared object load, check that there is an embedded checksum value
  in .rs.info and it matches the value computed in the previous step.
  The .so is not loaded if the checksums don't match.
- If invoking bcc, pass the checksum as an argument.

If ro.debuggable is not set, a constant checksum is added to .rs.info.
But it is never checked.

Change-Id: I0a9d16b34148b748daf744007a8515511714a5a5

1 files changed, 11 insertions, 2 deletions

diff --git a/cpu_ref/rsCpuExecutable.h b/cpu_ref/rsCpuExecutable.h
index acf092c8..cdf6fd6b 100644
--- a/cpu_ref/rsCpuExecutable.h
+++ b/cpu_ref/rsCpuExecutable.h
@@ -63,7 +63,7 @@ public:
                      size_t forEachCount,
                      const char ** pragmaKeys, const char ** pragmaValues,
                      size_t pragmaCount,
-                     bool isThreadable) :
+                     bool isThreadable, const char *buildChecksum) :
         mFieldAddress(fieldAddress), mFieldIsObject(fieldIsObject),
             mExportedVarCount(varCount),
             mInvokeFunctions(invokeFunctions), mFuncCount(funcCount),
@@ -71,7 +71,8 @@ public:
             mForEachCount(forEachCount),
             mPragmaKeys(pragmaKeys), mPragmaValues(pragmaValues),
             mPragmaCount(pragmaCount),
-            mIsThreadable(isThreadable), mRS(RSContext) {
+            mIsThreadable(isThreadable), mBuildChecksum(buildChecksum),
+            mRS(RSContext) {
     }
 
     ~ScriptExecutable() {
@@ -85,6 +86,7 @@ public:
             }
         }
 
+        delete[] mBuildChecksum;
         for (size_t i = 0; i < mPragmaCount; ++i) {
             delete [] mPragmaKeys[i];
             delete [] mPragmaValues[i];
@@ -118,6 +120,12 @@ public:
 
     bool getThreadable() const { return mIsThreadable; }
 
+    const char *getBuildChecksum() const { return mBuildChecksum; }
+    bool isChecksumValid(const char *checksum) const {
+      return (mBuildChecksum != nullptr &&
+              strcmp(checksum, mBuildChecksum) == 0);
+    }
+
 private:
     void** mFieldAddress;
     bool* mFieldIsObject;
@@ -135,6 +143,7 @@ private:
     size_t mPragmaCount;
 
     bool mIsThreadable;
+    const char *mBuildChecksum;
 
     Context* mRS;
 };