This PR adds ARMv8.4 cpu feature detection support. Previously we only needed ARMv8.1 and things were much easier. For example, ARMv8.1 `__ARM_FEATURE_CRYPTO` meant PMULL, AES, SHA-1 and SHA-256 were available. ARMv8.4 `__ARM_FEATURE_CRYPTO` means PMULL, AES, SHA-1, SHA-256, SHA-512, SHA-3, SM3 and SM4 are available.
We still use the same pattern as before. We make something available based on compiler version and/or preprocessor macros. But this time around we had to tighten things up a bit to ensure ARMv8.4 did not cross-pollinate down into ARMv8.1.
ARMv8.4 is largely untested at the moment. There is no hardware in the field and CI lacks QEMU with the relevant patches/support. We will probably have to revisit some of this stuff in the future.
Since this update applies to ARM gadgets we took the time to expand Android and iOS testing on Travis. Travis now tests more platforms, and includes Autotools and CMake builds, too.
This was needed a while ago but we mostly side-stepped the issues with casts. CHAM64 uses a word16 type for subkeys and a cast won't fix it because we favor word32 for 64-bit block sizes.
The ALTIVEC function required an inline declaration. Lack of inline caused the self test failure. Two NEON functions needed the same. We also cleaned up constants in unnamed namespaces
Analysis tools are generating findings when the pointer xorBlocks is used as the flag. The other missing piece is, xorBlocks is never NULL when either BT_XorInput or BT_XorOuput. But we don't know how to train the analyzers with the information, so we make it explicit with the boolean flags xorInput and xorOutput.
Switching to the explicit flags costs us about 0.01 cpb on a modern Intel Core processor. In the typical case 0.01 is negligible.
We were cating UBsan findings under Clang similar to "adv-simd.h:1138:26: runtime error: addition of unsigned offset to 0x000002d41410 overflowed to 0x000002d41400". The problem was CRYPTOPP_CONSTANT, which used an enum. The compiler is allowed to pick the underlying data type, and Clang was picking a signed type
This also fixes the SPECK64 bug where CTR mode self tests fail. It was an odd failure because it only affected 64-bit SPECK. SIMON was fine and it used nearly the same code. We tracked it down through trial and error to the table based rotates.
Jeffrey Walton
Fabrice Fontaine