diff options
| -rw-r--r-- | src/Makefile.am | 4 | ||||
| -rw-r--r-- | src/Makefile.bench.include | 1 | ||||
| -rw-r--r-- | src/bench/chacha_poly_aead.cpp | 123 | ||||
| -rw-r--r-- | src/crypto/chacha_poly_aead.cpp | 126 | ||||
| -rw-r--r-- | src/crypto/chacha_poly_aead.h | 146 | ||||
| -rw-r--r-- | src/test/crypto_tests.cpp | 126 |
6 files changed, 525 insertions, 1 deletions
diff --git a/src/Makefile.am b/src/Makefile.am index e4c542fa25..e86c580934 100644 --- a/src/Makefile.am +++ b/src/Makefile.am @@ -352,6 +352,8 @@ crypto_libbitcoin_crypto_base_a_CXXFLAGS = $(AM_CXXFLAGS) $(PIE_FLAGS) crypto_libbitcoin_crypto_base_a_SOURCES = \ crypto/aes.cpp \ crypto/aes.h \ + crypto/chacha_poly_aead.h \ + crypto/chacha_poly_aead.cpp \ crypto/chacha20.h \ crypto/chacha20.cpp \ crypto/common.h \ @@ -614,7 +616,7 @@ bitcoin_wallet_LDADD += $(BOOST_LIBS) $(BDB_LIBS) $(CRYPTO_LIBS) $(EVENT_PTHREAD # bitcoinconsensus library # if BUILD_BITCOIN_LIBS include_HEADERS = script/bitcoinconsensus.h -libbitcoinconsensus_la_SOURCES = $(crypto_libbitcoin_crypto_base_a_SOURCES) $(libbitcoin_consensus_a_SOURCES) +libbitcoinconsensus_la_SOURCES = support/cleanse.cpp $(crypto_libbitcoin_crypto_base_a_SOURCES) $(libbitcoin_consensus_a_SOURCES) if GLIBC_BACK_COMPAT libbitcoinconsensus_la_SOURCES += compat/glibc_compat.cpp diff --git a/src/Makefile.bench.include b/src/Makefile.bench.include index c1d9bf281c..e421b377a0 100644 --- a/src/Makefile.bench.include +++ b/src/Makefile.bench.include @@ -24,6 +24,7 @@ bench_bench_bitcoin_SOURCES = \ bench/examples.cpp \ bench/rollingbloom.cpp \ bench/chacha20.cpp \ + bench/chacha_poly_aead.cpp \ bench/crypto_hash.cpp \ bench/ccoins_caching.cpp \ bench/gcs_filter.cpp \ diff --git a/src/bench/chacha_poly_aead.cpp b/src/bench/chacha_poly_aead.cpp new file mode 100644 index 0000000000..f5f7297490 --- /dev/null +++ b/src/bench/chacha_poly_aead.cpp @@ -0,0 +1,123 @@ +// Copyright (c) 2019 The Bitcoin Core developers +// Distributed under the MIT software license, see the accompanying +// file COPYING or http://www.opensource.org/licenses/mit-license.php. + +#include <iostream> + +#include <bench/bench.h> +#include <crypto/chacha_poly_aead.h> +#include <crypto/poly1305.h> // for the POLY1305_TAGLEN constant +#include <hash.h> + +#include <limits> +#include <assert.h> + +/* Number of bytes to process per iteration */ +static constexpr uint64_t BUFFER_SIZE_TINY = 64; +static constexpr uint64_t BUFFER_SIZE_SMALL = 256; +static constexpr uint64_t BUFFER_SIZE_LARGE = 1024 * 1024; + +static const unsigned char k1[32] = {0}; +static const unsigned char k2[32] = {0}; + +static ChaCha20Poly1305AEAD aead(k1, 32, k2, 32); + +static void CHACHA20_POLY1305_AEAD(benchmark::State& state, size_t buffersize, bool include_decryption) +{ + std::vector<unsigned char> in(buffersize + CHACHA20_POLY1305_AEAD_AAD_LEN + POLY1305_TAGLEN, 0); + std::vector<unsigned char> out(buffersize + CHACHA20_POLY1305_AEAD_AAD_LEN + POLY1305_TAGLEN, 0); + uint64_t seqnr_payload = 0; + uint64_t seqnr_aad = 0; + int aad_pos = 0; + uint32_t len = 0; + while (state.KeepRunning()) { + // encrypt or decrypt the buffer with a static key + assert(aead.Crypt(seqnr_payload, seqnr_aad, aad_pos, out.data(), out.size(), in.data(), buffersize, true)); + + if (include_decryption) { + // if we decrypt, include the GetLength + assert(aead.GetLength(&len, seqnr_aad, aad_pos, in.data())); + assert(aead.Crypt(seqnr_payload, seqnr_aad, aad_pos, out.data(), out.size(), in.data(), buffersize, true)); + } + + // increase main sequence number + seqnr_payload++; + // increase aad position (position in AAD keystream) + aad_pos += CHACHA20_POLY1305_AEAD_AAD_LEN; + if (aad_pos + CHACHA20_POLY1305_AEAD_AAD_LEN > CHACHA20_ROUND_OUTPUT) { + aad_pos = 0; + seqnr_aad++; + } + if (seqnr_payload + 1 == std::numeric_limits<uint64_t>::max()) { + // reuse of nonce+key is okay while benchmarking. + seqnr_payload = 0; + seqnr_aad = 0; + aad_pos = 0; + } + } +} + +static void CHACHA20_POLY1305_AEAD_64BYTES_ONLY_ENCRYPT(benchmark::State& state) +{ + CHACHA20_POLY1305_AEAD(state, BUFFER_SIZE_TINY, false); +} + +static void CHACHA20_POLY1305_AEAD_256BYTES_ONLY_ENCRYPT(benchmark::State& state) +{ + CHACHA20_POLY1305_AEAD(state, BUFFER_SIZE_SMALL, false); +} + +static void CHACHA20_POLY1305_AEAD_1MB_ONLY_ENCRYPT(benchmark::State& state) +{ + CHACHA20_POLY1305_AEAD(state, BUFFER_SIZE_LARGE, false); +} + +static void CHACHA20_POLY1305_AEAD_64BYTES_ENCRYPT_DECRYPT(benchmark::State& state) +{ + CHACHA20_POLY1305_AEAD(state, BUFFER_SIZE_TINY, true); +} + +static void CHACHA20_POLY1305_AEAD_256BYTES_ENCRYPT_DECRYPT(benchmark::State& state) +{ + CHACHA20_POLY1305_AEAD(state, BUFFER_SIZE_SMALL, true); +} + +static void CHACHA20_POLY1305_AEAD_1MB_ENCRYPT_DECRYPT(benchmark::State& state) +{ + CHACHA20_POLY1305_AEAD(state, BUFFER_SIZE_LARGE, true); +} + +// Add Hash() (dbl-sha256) bench for comparison + +static void HASH(benchmark::State& state, size_t buffersize) +{ + uint8_t hash[CHash256::OUTPUT_SIZE]; + std::vector<uint8_t> in(buffersize,0); + while (state.KeepRunning()) + CHash256().Write(in.data(), in.size()).Finalize(hash); +} + +static void HASH_64BYTES(benchmark::State& state) +{ + HASH(state, BUFFER_SIZE_TINY); +} + +static void HASH_256BYTES(benchmark::State& state) +{ + HASH(state, BUFFER_SIZE_SMALL); +} + +static void HASH_1MB(benchmark::State& state) +{ + HASH(state, BUFFER_SIZE_LARGE); +} + +BENCHMARK(CHACHA20_POLY1305_AEAD_64BYTES_ONLY_ENCRYPT, 500000); +BENCHMARK(CHACHA20_POLY1305_AEAD_256BYTES_ONLY_ENCRYPT, 250000); +BENCHMARK(CHACHA20_POLY1305_AEAD_1MB_ONLY_ENCRYPT, 340); +BENCHMARK(CHACHA20_POLY1305_AEAD_64BYTES_ENCRYPT_DECRYPT, 500000); +BENCHMARK(CHACHA20_POLY1305_AEAD_256BYTES_ENCRYPT_DECRYPT, 250000); +BENCHMARK(CHACHA20_POLY1305_AEAD_1MB_ENCRYPT_DECRYPT, 340); +BENCHMARK(HASH_64BYTES, 500000); +BENCHMARK(HASH_256BYTES, 250000); +BENCHMARK(HASH_1MB, 340); diff --git a/src/crypto/chacha_poly_aead.cpp b/src/crypto/chacha_poly_aead.cpp new file mode 100644 index 0000000000..6a3d43deb1 --- /dev/null +++ b/src/crypto/chacha_poly_aead.cpp @@ -0,0 +1,126 @@ +// Copyright (c) 2019 The Bitcoin Core developers +// Distributed under the MIT software license, see the accompanying +// file COPYING or http://www.opensource.org/licenses/mit-license.php. + +#include <crypto/chacha_poly_aead.h> + +#include <crypto/common.h> +#include <crypto/poly1305.h> +#include <support/cleanse.h> + +#include <assert.h> +#include <string.h> + +#include <cstdio> +#include <limits> + +#ifndef HAVE_TIMINGSAFE_BCMP + +int timingsafe_bcmp(const unsigned char* b1, const unsigned char* b2, size_t n) +{ + const unsigned char *p1 = b1, *p2 = b2; + int ret = 0; + + for (; n > 0; n--) + ret |= *p1++ ^ *p2++; + return (ret != 0); +} + +#endif // TIMINGSAFE_BCMP + +ChaCha20Poly1305AEAD::ChaCha20Poly1305AEAD(const unsigned char* K_1, size_t K_1_len, const unsigned char* K_2, size_t K_2_len) +{ + assert(K_1_len == CHACHA20_POLY1305_AEAD_KEY_LEN); + assert(K_2_len == CHACHA20_POLY1305_AEAD_KEY_LEN); + m_chacha_main.SetKey(K_1, CHACHA20_POLY1305_AEAD_KEY_LEN); + m_chacha_header.SetKey(K_2, CHACHA20_POLY1305_AEAD_KEY_LEN); + + // set the cached sequence number to uint64 max which hints for an unset cache. + // we can't hit uint64 max since the rekey rule (which resets the sequence number) is 1GB + m_cached_aad_seqnr = std::numeric_limits<uint64_t>::max(); +} + +bool ChaCha20Poly1305AEAD::Crypt(uint64_t seqnr_payload, uint64_t seqnr_aad, int aad_pos, unsigned char* dest, size_t dest_len /* length of the output buffer for sanity checks */, const unsigned char* src, size_t src_len, bool is_encrypt) +{ + // check buffer boundaries + if ( + // if we encrypt, make sure the source contains at least the expected AAD and the destination has at least space for the source + MAC + (is_encrypt && (src_len < CHACHA20_POLY1305_AEAD_AAD_LEN || dest_len < src_len + POLY1305_TAGLEN)) || + // if we decrypt, make sure the source contains at least the expected AAD+MAC and the destination has at least space for the source - MAC + (!is_encrypt && (src_len < CHACHA20_POLY1305_AEAD_AAD_LEN + POLY1305_TAGLEN || dest_len < src_len - POLY1305_TAGLEN))) { + return false; + } + + unsigned char expected_tag[POLY1305_TAGLEN], poly_key[POLY1305_KEYLEN]; + memset(poly_key, 0, sizeof(poly_key)); + m_chacha_main.SetIV(seqnr_payload); + + // block counter 0 for the poly1305 key + // use lower 32bytes for the poly1305 key + // (throws away 32 unused bytes (upper 32) from this ChaCha20 round) + m_chacha_main.Seek(0); + m_chacha_main.Crypt(poly_key, poly_key, sizeof(poly_key)); + + // if decrypting, verify the tag prior to decryption + if (!is_encrypt) { + const unsigned char* tag = src + src_len - POLY1305_TAGLEN; + poly1305_auth(expected_tag, src, src_len - POLY1305_TAGLEN, poly_key); + + // constant time compare the calculated MAC with the provided MAC + if (timingsafe_bcmp(expected_tag, tag, POLY1305_TAGLEN) != 0) { + memory_cleanse(expected_tag, sizeof(expected_tag)); + memory_cleanse(poly_key, sizeof(poly_key)); + return false; + } + memory_cleanse(expected_tag, sizeof(expected_tag)); + // MAC has been successfully verified, make sure we don't covert it in decryption + src_len -= POLY1305_TAGLEN; + } + + // calculate and cache the next 64byte keystream block if requested sequence number is not yet the cache + if (m_cached_aad_seqnr != seqnr_aad) { + m_cached_aad_seqnr = seqnr_aad; + m_chacha_header.SetIV(seqnr_aad); + m_chacha_header.Seek(0); + m_chacha_header.Keystream(m_aad_keystream_buffer, CHACHA20_ROUND_OUTPUT); + } + // crypt the AAD (3 bytes message length) with given position in AAD cipher instance keystream + dest[0] = src[0] ^ m_aad_keystream_buffer[aad_pos]; + dest[1] = src[1] ^ m_aad_keystream_buffer[aad_pos + 1]; + dest[2] = src[2] ^ m_aad_keystream_buffer[aad_pos + 2]; + + // Set the playload ChaCha instance block counter to 1 and crypt the payload + m_chacha_main.Seek(1); + m_chacha_main.Crypt(src + CHACHA20_POLY1305_AEAD_AAD_LEN, dest + CHACHA20_POLY1305_AEAD_AAD_LEN, src_len - CHACHA20_POLY1305_AEAD_AAD_LEN); + + // If encrypting, calculate and append tag + if (is_encrypt) { + // the poly1305 tag expands over the AAD (3 bytes length) & encrypted payload + poly1305_auth(dest + src_len, dest, src_len, poly_key); + } + + // cleanse no longer required MAC and polykey + memory_cleanse(poly_key, sizeof(poly_key)); + return true; +} + +bool ChaCha20Poly1305AEAD::GetLength(uint32_t* len24_out, uint64_t seqnr_aad, int aad_pos, const uint8_t* ciphertext) +{ + // enforce valid aad position to avoid accessing outside of the 64byte keystream cache + // (there is space for 21 times 3 bytes) + assert(aad_pos >= 0 && aad_pos < CHACHA20_ROUND_OUTPUT - CHACHA20_POLY1305_AEAD_AAD_LEN); + if (m_cached_aad_seqnr != seqnr_aad) { + // we need to calculate the 64 keystream bytes since we reached a new aad sequence number + m_cached_aad_seqnr = seqnr_aad; + m_chacha_header.SetIV(seqnr_aad); // use LE for the nonce + m_chacha_header.Seek(0); // block counter 0 + m_chacha_header.Keystream(m_aad_keystream_buffer, CHACHA20_ROUND_OUTPUT); // write keystream to the cache + } + + // decrypt the ciphertext length by XORing the right position of the 64byte keystream cache with the ciphertext + *len24_out = (ciphertext[0] ^ m_aad_keystream_buffer[aad_pos + 0]) | + (ciphertext[1] ^ m_aad_keystream_buffer[aad_pos + 1]) << 8 | + (ciphertext[2] ^ m_aad_keystream_buffer[aad_pos + 2]) << 16; + + return true; +} diff --git a/src/crypto/chacha_poly_aead.h b/src/crypto/chacha_poly_aead.h new file mode 100644 index 0000000000..b3ba781cdd --- /dev/null +++ b/src/crypto/chacha_poly_aead.h @@ -0,0 +1,146 @@ +// Copyright (c) 2019 The Bitcoin Core developers +// Distributed under the MIT software license, see the accompanying +// file COPYING or http://www.opensource.org/licenses/mit-license.php. + +#ifndef BITCOIN_CRYPTO_CHACHA_POLY_AEAD_H +#define BITCOIN_CRYPTO_CHACHA_POLY_AEAD_H + +#include <crypto/chacha20.h> + +#include <cmath> + +static constexpr int CHACHA20_POLY1305_AEAD_KEY_LEN = 32; +static constexpr int CHACHA20_POLY1305_AEAD_AAD_LEN = 3; /* 3 bytes length */ +static constexpr int CHACHA20_ROUND_OUTPUT = 64; /* 64 bytes per round */ +static constexpr int AAD_PACKAGES_PER_ROUND = 21; /* 64 / 3 round down*/ + +/* A AEAD class for ChaCha20-Poly1305@bitcoin. + * + * ChaCha20 is a stream cipher designed by Daniel Bernstein and described in + * <ref>[http://cr.yp.to/chacha/chacha-20080128.pdf ChaCha20]</ref>. It operates + * by permuting 128 fixed bits, 128 or 256 bits of key, a 64 bit nonce and a 64 + * bit counter into 64 bytes of output. This output is used as a keystream, with + * any unused bytes simply discarded. + * + * Poly1305 <ref>[http://cr.yp.to/mac/poly1305-20050329.pdf Poly1305]</ref>, also + * by Daniel Bernstein, is a one-time Carter-Wegman MAC that computes a 128 bit + * integrity tag given a message and a single-use 256 bit secret key. + * + * The chacha20-poly1305@bitcoin combines these two primitives into an + * authenticated encryption mode. The construction used is based on that proposed + * for TLS by Adam Langley in + * <ref>[http://tools.ietf.org/html/draft-agl-tls-chacha20poly1305-03 "ChaCha20 + * and Poly1305 based Cipher Suites for TLS", Adam Langley]</ref>, but differs in + * the layout of data passed to the MAC and in the addition of encryption of the + * packet lengths. + * + * ==== Detailed Construction ==== + * + * The chacha20-poly1305@bitcoin cipher requires two 256 bits of key material as + * output from the key exchange. Each key (K_1 and K_2) are used by two separate + * instances of chacha20. + * + * The instance keyed by K_1 is a stream cipher that is used only to encrypt the 3 + * byte packet length field and has its own sequence number. The second instance, + * keyed by K_2, is used in conjunction with poly1305 to build an AEAD + * (Authenticated Encryption with Associated Data) that is used to encrypt and + * authenticate the entire packet. + * + * Two separate cipher instances are used here so as to keep the packet lengths + * confidential but not create an oracle for the packet payload cipher by + * decrypting and using the packet length prior to checking the MAC. By using an + * independently-keyed cipher instance to encrypt the length, an active attacker + * seeking to exploit the packet input handling as a decryption oracle can learn + * nothing about the payload contents or its MAC (assuming key derivation, + * ChaCha20 and Poly1305 are secure). + * + * The AEAD is constructed as follows: for each packet, generate a Poly1305 key by + * taking the first 256 bits of ChaCha20 stream output generated using K_2, an IV + * consisting of the packet sequence number encoded as an LE uint64 and a ChaCha20 + * block counter of zero. The K_2 ChaCha20 block counter is then set to the + * little-endian encoding of 1 (i.e. {1, 0, 0, 0, 0, 0, 0, 0}) and this instance + * is used for encryption of the packet payload. + * + * ==== Packet Handling ==== + * + * When receiving a packet, the length must be decrypted first. When 3 bytes of + * ciphertext length have been received, they may be decrypted. + * + * A ChaCha20 round always calculates 64bytes which is sufficient to crypt 21 + * times a 3 bytes length field (21*3 = 63). The length field sequence number can + * thus be used 21 times (keystream caching). + * + * The length field must be enc-/decrypted with the ChaCha20 keystream keyed with + * K_1 defined by block counter 0, the length field sequence number in little + * endian and a keystream position from 0 to 60. + * + * Once the entire packet has been received, the MAC MUST be checked before + * decryption. A per-packet Poly1305 key is generated as described above and the + * MAC tag calculated using Poly1305 with this key over the ciphertext of the + * packet length and the payload together. The calculated MAC is then compared in + * constant time with the one appended to the packet and the packet decrypted + * using ChaCha20 as described above (with K_2, the packet sequence number as + * nonce and a starting block counter of 1). + * + * Detection of an invalid MAC MUST lead to immediate connection termination. + * + * To send a packet, first encode the 3 byte length and encrypt it using K_1 as + * described above. Encrypt the packet payload (using K_2) and append it to the + * encrypted length. Finally, calculate a MAC tag and append it. + * + * The initiating peer MUST use <code>K_1_A, K_2_A</code> to encrypt messages on + * the send channel, <code>K_1_B, K_2_B</code> MUST be used to decrypt messages on + * the receive channel. + * + * The responding peer MUST use <code>K_1_A, K_2_A</code> to decrypt messages on + * the receive channel, <code>K_1_B, K_2_B</code> MUST be used to encrypt messages + * on the send channel. + * + * Optimized implementations of ChaCha20-Poly1305@bitcoin are relatively fast in + * general, therefore it is very likely that encrypted messages require not more + * CPU cycles per bytes then the current unencrypted p2p message format + * (ChaCha20/Poly1305 versus double SHA256). + * + * The initial packet sequence numbers are 0. + * + * K_2 ChaCha20 cipher instance (payload) must never reuse a {key, nonce} for + * encryption nor may it be used to encrypt more than 2^70 bytes under the same + * {key, nonce}. + * + * K_1 ChaCha20 cipher instance (length field/AAD) must never reuse a {key, nonce, + * position-in-keystream} for encryption nor may it be used to encrypt more than + * 2^70 bytes under the same {key, nonce}. + * + * We use message sequence numbers for both communication directions. + */ + +class ChaCha20Poly1305AEAD +{ +private: + ChaCha20 m_chacha_main; // payload and poly1305 key-derivation cipher instance + ChaCha20 m_chacha_header; // AAD cipher instance (encrypted length) + unsigned char m_aad_keystream_buffer[CHACHA20_ROUND_OUTPUT]; // aad keystream cache + uint64_t m_cached_aad_seqnr; // aad keystream cache hint + +public: + ChaCha20Poly1305AEAD(const unsigned char* K_1, size_t K_1_len, const unsigned char* K_2, size_t K_2_len); + + explicit ChaCha20Poly1305AEAD(const ChaCha20Poly1305AEAD&) = delete; + + /** Encrypts/decrypts a packet + seqnr_payload, the message sequence number + seqnr_aad, the messages AAD sequence number which allows reuse of the AAD keystream + aad_pos, position to use in the AAD keystream to encrypt the AAD + dest, output buffer, must be of a size equal or larger then CHACHA20_POLY1305_AEAD_AAD_LEN + payload (+ POLY1305_TAG_LEN in encryption) bytes + destlen, length of the destination buffer + src, the AAD+payload to encrypt or the AAD+payload+MAC to decrypt + src_len, the length of the source buffer + is_encrypt, set to true if we encrypt (creates and appends the MAC instead of verifying it) + */ + bool Crypt(uint64_t seqnr_payload, uint64_t seqnr_aad, int aad_pos, unsigned char* dest, size_t dest_len, const unsigned char* src, size_t src_len, bool is_encrypt); + + /** decrypts the 3 bytes AAD data and decodes it into a uint32_t field */ + bool GetLength(uint32_t* len24_out, uint64_t seqnr_aad, int aad_pos, const uint8_t* ciphertext); +}; + +#endif // BITCOIN_CRYPTO_CHACHA_POLY_AEAD_H diff --git a/src/test/crypto_tests.cpp b/src/test/crypto_tests.cpp index 4e2acca4c3..4ac12bf969 100644 --- a/src/test/crypto_tests.cpp +++ b/src/test/crypto_tests.cpp @@ -4,6 +4,7 @@ #include <crypto/aes.h> #include <crypto/chacha20.h> +#include <crypto/chacha_poly_aead.h> #include <crypto/poly1305.h> #include <crypto/hkdf_sha256_32.h> #include <crypto/hmac_sha256.h> @@ -585,6 +586,131 @@ BOOST_AUTO_TEST_CASE(hkdf_hmac_sha256_l32_tests) "8da4e775a563c18f715f802a063c5a31b8a11f5c5ee1879ec3454e5f3c738d2d"); } +static void TestChaCha20Poly1305AEAD(bool must_succeed, unsigned int expected_aad_length, const std::string& hex_m, const std::string& hex_k1, const std::string& hex_k2, const std::string& hex_aad_keystream, const std::string& hex_encrypted_message, const std::string& hex_encrypted_message_seq_999) +{ + // we need two sequence numbers, one for the payload cipher instance... + uint32_t seqnr_payload = 0; + // ... and one for the AAD (length) cipher instance + uint32_t seqnr_aad = 0; + // we need to keep track of the position in the AAD cipher instance + // keystream since we use the same 64byte output 21 times + // (21 times 3 bytes length < 64) + int aad_pos = 0; + + std::vector<unsigned char> aead_K_1 = ParseHex(hex_k1); + std::vector<unsigned char> aead_K_2 = ParseHex(hex_k2); + std::vector<unsigned char> plaintext_buf = ParseHex(hex_m); + std::vector<unsigned char> expected_aad_keystream = ParseHex(hex_aad_keystream); + std::vector<unsigned char> expected_ciphertext_and_mac = ParseHex(hex_encrypted_message); + std::vector<unsigned char> expected_ciphertext_and_mac_sequence999 = ParseHex(hex_encrypted_message_seq_999); + + std::vector<unsigned char> ciphertext_buf(plaintext_buf.size() + POLY1305_TAGLEN, 0); + std::vector<unsigned char> plaintext_buf_new(plaintext_buf.size(), 0); + std::vector<unsigned char> cmp_ctx_buffer(64); + uint32_t out_len = 0; + + // create the AEAD instance + ChaCha20Poly1305AEAD aead(aead_K_1.data(), aead_K_1.size(), aead_K_2.data(), aead_K_2.size()); + + // create a chacha20 instance to compare against + ChaCha20 cmp_ctx(aead_K_2.data(), 32); + + // encipher + bool res = aead.Crypt(seqnr_payload, seqnr_aad, aad_pos, ciphertext_buf.data(), ciphertext_buf.size(), plaintext_buf.data(), plaintext_buf.size(), true); + // make sure the operation succeeded if expected to succeed + BOOST_CHECK_EQUAL(res, must_succeed); + if (!res) return; + + // verify ciphertext & mac against the test vector + BOOST_CHECK_EQUAL(expected_ciphertext_and_mac.size(), ciphertext_buf.size()); + BOOST_CHECK(memcmp(ciphertext_buf.data(), expected_ciphertext_and_mac.data(), ciphertext_buf.size()) == 0); + + // manually construct the AAD keystream + cmp_ctx.SetIV(seqnr_aad); + cmp_ctx.Seek(0); + cmp_ctx.Keystream(cmp_ctx_buffer.data(), 64); + BOOST_CHECK(memcmp(expected_aad_keystream.data(), cmp_ctx_buffer.data(), expected_aad_keystream.size()) == 0); + // crypt the 3 length bytes and compare the length + uint32_t len_cmp = 0; + len_cmp = (ciphertext_buf[0] ^ cmp_ctx_buffer[aad_pos + 0]) | + (ciphertext_buf[1] ^ cmp_ctx_buffer[aad_pos + 1]) << 8 | + (ciphertext_buf[2] ^ cmp_ctx_buffer[aad_pos + 2]) << 16; + BOOST_CHECK_EQUAL(len_cmp, expected_aad_length); + + // encrypt / decrypt 1000 packets + for (size_t i = 0; i < 1000; ++i) { + res = aead.Crypt(seqnr_payload, seqnr_aad, aad_pos, ciphertext_buf.data(), ciphertext_buf.size(), plaintext_buf.data(), plaintext_buf.size(), true); + BOOST_CHECK(res); + BOOST_CHECK(aead.GetLength(&out_len, seqnr_aad, aad_pos, ciphertext_buf.data())); + BOOST_CHECK_EQUAL(out_len, expected_aad_length); + res = aead.Crypt(seqnr_payload, seqnr_aad, aad_pos, plaintext_buf_new.data(), plaintext_buf_new.size(), ciphertext_buf.data(), ciphertext_buf.size(), false); + BOOST_CHECK(res); + + // make sure we repetitive get the same plaintext + BOOST_CHECK(memcmp(plaintext_buf.data(), plaintext_buf_new.data(), plaintext_buf.size()) == 0); + + // compare sequence number 999 against the test vector + if (seqnr_payload == 999) { + BOOST_CHECK(memcmp(ciphertext_buf.data(), expected_ciphertext_and_mac_sequence999.data(), expected_ciphertext_and_mac_sequence999.size()) == 0); + } + // set nonce and block counter, output the keystream + cmp_ctx.SetIV(seqnr_aad); + cmp_ctx.Seek(0); + cmp_ctx.Keystream(cmp_ctx_buffer.data(), 64); + + // crypt the 3 length bytes and compare the length + len_cmp = 0; + len_cmp = (ciphertext_buf[0] ^ cmp_ctx_buffer[aad_pos + 0]) | + (ciphertext_buf[1] ^ cmp_ctx_buffer[aad_pos + 1]) << 8 | + (ciphertext_buf[2] ^ cmp_ctx_buffer[aad_pos + 2]) << 16; + BOOST_CHECK_EQUAL(len_cmp, expected_aad_length); + + // increment the sequence number(s) + // always increment the payload sequence number + // increment the AAD keystream position by its size (3) + // increment the AAD sequence number if we would hit the 64 byte limit + seqnr_payload++; + aad_pos += CHACHA20_POLY1305_AEAD_AAD_LEN; + if (aad_pos + CHACHA20_POLY1305_AEAD_AAD_LEN > CHACHA20_ROUND_OUTPUT) { + aad_pos = 0; + seqnr_aad++; + } + } +} + +BOOST_AUTO_TEST_CASE(chacha20_poly1305_aead_testvector) +{ + /* test chacha20poly1305@bitcoin AEAD */ + + // must fail with no message + TestChaCha20Poly1305AEAD(false, 0, + "", + "0000000000000000000000000000000000000000000000000000000000000000", + "0000000000000000000000000000000000000000000000000000000000000000", "", "", ""); + + TestChaCha20Poly1305AEAD(true, 0, + /* m */ "0000000000000000000000000000000000000000000000000000000000000000", + /* k1 (payload) */ "0000000000000000000000000000000000000000000000000000000000000000", + /* k2 (AAD) */ "0000000000000000000000000000000000000000000000000000000000000000", + /* AAD keystream */ "76b8e0ada0f13d90405d6ae55386bd28bdd219b8a08ded1aa836efcc8b770dc7da41597c5157488d7724e03fb8d84a376a43b8f41518a11cc387b669b2ee6586", + /* encrypted message & MAC */ "76b8e09f07e7be5551387a98ba977c732d080dcb0f29a048e3656912c6533e32d2fc11829c1b6c1df1f551cd6131ff08", + /* encrypted message & MAC at sequence 999 */ "b0a03d5bd2855d60699e7d3a3133fa47be740fe4e4c1f967555e2d9271f31c3aaa7aa16ec62c5e24f040c08bb20c3598"); + TestChaCha20Poly1305AEAD(true, 1, + "0100000000000000000000000000000000000000000000000000000000000000", + "0000000000000000000000000000000000000000000000000000000000000000", + "0000000000000000000000000000000000000000000000000000000000000000", + "76b8e0ada0f13d90405d6ae55386bd28bdd219b8a08ded1aa836efcc8b770dc7da41597c5157488d7724e03fb8d84a376a43b8f41518a11cc387b669b2ee6586", + "77b8e09f07e7be5551387a98ba977c732d080dcb0f29a048e3656912c6533e32baf0c85b6dff8602b06cf52a6aefc62e", + "b1a03d5bd2855d60699e7d3a3133fa47be740fe4e4c1f967555e2d9271f31c3a8bd94d54b5ecabbc41ffbb0c90924080"); + TestChaCha20Poly1305AEAD(true, 255, + "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", + "000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f", + "ff0102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f", + "c640c1711e3ee904ac35c57ab9791c8a1c408603a90b77a83b54f6c844cb4b06d94e7fc6c800e165acd66147e80ec45a567f6ce66d05ec0cae679dceeb890017", + "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", + "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"); +} + BOOST_AUTO_TEST_CASE(countbits_tests) { FastRandomContext ctx; |