| //==- BLAKE3.h - BLAKE3 C++ wrapper for LLVM ---------------------*- C++ -*-==// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This is a C++ wrapper of the BLAKE3 C interface. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef LLVM_SUPPORT_BLAKE3_H |
| #define LLVM_SUPPORT_BLAKE3_H |
| |
| #include "llvm-c/blake3.h" |
| #include "llvm/ADT/ArrayRef.h" |
| #include "llvm/ADT/StringRef.h" |
| |
| namespace llvm { |
| |
| /// The constant \p LLVM_BLAKE3_OUT_LEN provides the default output length, |
| /// 32 bytes, which is recommended for most callers. |
| /// |
| /// Outputs shorter than the default length of 32 bytes (256 bits) provide |
| /// less security. An N-bit BLAKE3 output is intended to provide N bits of |
| /// first and second preimage resistance and N/2 bits of collision |
| /// resistance, for any N up to 256. Longer outputs don't provide any |
| /// additional security. |
| /// |
| /// Shorter BLAKE3 outputs are prefixes of longer ones. Explicitly |
| /// requesting a short output is equivalent to truncating the default-length |
| /// output. |
| template <size_t NumBytes = LLVM_BLAKE3_OUT_LEN> |
| using BLAKE3Result = std::array<uint8_t, NumBytes>; |
| |
| /// A class that wraps the BLAKE3 algorithm. |
| class BLAKE3 { |
| public: |
| BLAKE3() { init(); } |
| |
| /// Reinitialize the internal state |
| void init() { llvm_blake3_hasher_init(&Hasher); } |
| |
| /// Digest more data. |
| void update(ArrayRef<uint8_t> Data) { |
| llvm_blake3_hasher_update(&Hasher, Data.data(), Data.size()); |
| } |
| |
| /// Digest more data. |
| void update(StringRef Str) { |
| llvm_blake3_hasher_update(&Hasher, Str.data(), Str.size()); |
| } |
| |
| /// Finalize the hasher and put the result in \p Result. |
| /// This doesn't modify the hasher itself, and it's possible to finalize again |
| /// after adding more input. |
| template <size_t NumBytes = LLVM_BLAKE3_OUT_LEN> |
| void final(BLAKE3Result<NumBytes> &Result) { |
| llvm_blake3_hasher_finalize(&Hasher, Result.data(), Result.size()); |
| } |
| |
| /// Finalize the hasher and return an output of any length, given in bytes. |
| /// This doesn't modify the hasher itself, and it's possible to finalize again |
| /// after adding more input. |
| template <size_t NumBytes = LLVM_BLAKE3_OUT_LEN> |
| BLAKE3Result<NumBytes> final() { |
| BLAKE3Result<NumBytes> Result; |
| llvm_blake3_hasher_finalize(&Hasher, Result.data(), Result.size()); |
| return Result; |
| } |
| |
| /// Return the current output for the digested data since the last call to |
| /// init(). |
| /// |
| /// Other hash functions distinguish between \p result() and \p final(), with |
| /// \p result() allowing more calls into \p update(), but there's no |
| // difference for the BLAKE3 hash function. |
| template <size_t NumBytes = LLVM_BLAKE3_OUT_LEN> |
| BLAKE3Result<NumBytes> result() { |
| return final<NumBytes>(); |
| } |
| |
| /// Returns a BLAKE3 hash for the given data. |
| template <size_t NumBytes = LLVM_BLAKE3_OUT_LEN> |
| static BLAKE3Result<NumBytes> hash(ArrayRef<uint8_t> Data) { |
| BLAKE3 Hasher; |
| Hasher.update(Data); |
| return Hasher.final<NumBytes>(); |
| } |
| |
| private: |
| llvm_blake3_hasher Hasher; |
| }; |
| |
| /// Like \p BLAKE3 but using a class-level template parameter for specifying the |
| /// hash size of the \p final() and \p result() functions. |
| /// |
| /// This is useful for using BLAKE3 as the hasher type for \p HashBuilder with |
| /// non-default hash sizes. |
| template <size_t NumBytes> class TruncatedBLAKE3 : public BLAKE3 { |
| public: |
| /// Finalize the hasher and put the result in \p Result. |
| /// This doesn't modify the hasher itself, and it's possible to finalize again |
| /// after adding more input. |
| void final(BLAKE3Result<NumBytes> &Result) { return BLAKE3::final(Result); } |
| |
| /// Finalize the hasher and return an output of any length, given in bytes. |
| /// This doesn't modify the hasher itself, and it's possible to finalize again |
| /// after adding more input. |
| BLAKE3Result<NumBytes> final() { return BLAKE3::final<NumBytes>(); } |
| |
| /// Return the current output for the digested data since the last call to |
| /// init(). |
| /// |
| /// Other hash functions distinguish between \p result() and \p final(), with |
| /// \p result() allowing more calls into \p update(), but there's no |
| // difference for the BLAKE3 hash function. |
| BLAKE3Result<NumBytes> result() { return BLAKE3::result<NumBytes>(); } |
| }; |
| |
| } // namespace llvm |
| |
| #endif |