mirror of
https://github.com/oxen-io/lokinet.git
synced 2024-11-03 23:15:52 +00:00
7caa87862e
All #ifndef guards on headers have been removed, I think, in favor of #pragma once Headers are now included as `#include "filename"` if the included file resides in the same directory as the file including it, or any subdirectory therein. Otherwise they are included as `#include <project/top/dir/relative/path/filename>` The above does not include system/os headers.
495 lines
14 KiB
C++
495 lines
14 KiB
C++
#include "crypto_libsodium.hpp"
|
|
#include <sodium/crypto_generichash.h>
|
|
#include <sodium/crypto_sign.h>
|
|
#include <sodium/crypto_scalarmult.h>
|
|
#include <sodium/crypto_scalarmult_ed25519.h>
|
|
#include <sodium/crypto_stream_xchacha20.h>
|
|
#include <sodium/crypto_core_ed25519.h>
|
|
#include <sodium/crypto_aead_xchacha20poly1305.h>
|
|
#include <sodium/randombytes.h>
|
|
#include <sodium/utils.h>
|
|
#include <llarp/util/mem.hpp>
|
|
#include <llarp/util/endian.hpp>
|
|
#include <llarp/util/str.hpp>
|
|
#include <cassert>
|
|
#include <cstring>
|
|
|
|
extern "C"
|
|
{
|
|
extern int
|
|
sodium_init(void);
|
|
}
|
|
|
|
namespace llarp
|
|
{
|
|
namespace sodium
|
|
{
|
|
static bool
|
|
dh(llarp::SharedSecret& out,
|
|
const PubKey& client_pk,
|
|
const PubKey& server_pk,
|
|
const uint8_t* themPub,
|
|
const SecretKey& usSec)
|
|
{
|
|
llarp::SharedSecret shared;
|
|
crypto_generichash_state h;
|
|
|
|
if (crypto_scalarmult_curve25519(shared.data(), usSec.data(), themPub))
|
|
{
|
|
return false;
|
|
}
|
|
crypto_generichash_blake2b_init(&h, nullptr, 0U, shared.size());
|
|
crypto_generichash_blake2b_update(&h, client_pk.data(), 32);
|
|
crypto_generichash_blake2b_update(&h, server_pk.data(), 32);
|
|
crypto_generichash_blake2b_update(&h, shared.data(), 32);
|
|
crypto_generichash_blake2b_final(&h, out.data(), shared.size());
|
|
return true;
|
|
}
|
|
|
|
static bool
|
|
dh_client_priv(
|
|
llarp::SharedSecret& shared, const PubKey& pk, const SecretKey& sk, const TunnelNonce& n)
|
|
{
|
|
llarp::SharedSecret dh_result;
|
|
|
|
if (dh(dh_result, sk.toPublic(), pk, pk.data(), sk))
|
|
{
|
|
return crypto_generichash_blake2b(shared.data(), 32, n.data(), 32, dh_result.data(), 32)
|
|
!= -1;
|
|
}
|
|
llarp::LogWarn("crypto::dh_client - dh failed");
|
|
return false;
|
|
}
|
|
|
|
static bool
|
|
dh_server_priv(
|
|
llarp::SharedSecret& shared, const PubKey& pk, const SecretKey& sk, const TunnelNonce& n)
|
|
{
|
|
llarp::SharedSecret dh_result;
|
|
if (dh(dh_result, pk, sk.toPublic(), pk.data(), sk))
|
|
{
|
|
return crypto_generichash_blake2b(shared.data(), 32, n.data(), 32, dh_result.data(), 32)
|
|
!= -1;
|
|
}
|
|
llarp::LogWarn("crypto::dh_server - dh failed");
|
|
return false;
|
|
}
|
|
|
|
CryptoLibSodium::CryptoLibSodium()
|
|
{
|
|
if (sodium_init() == -1)
|
|
{
|
|
throw std::runtime_error("sodium_init() returned -1");
|
|
}
|
|
char* avx2 = std::getenv("AVX2_FORCE_DISABLE");
|
|
if (avx2 && std::string(avx2) == "1")
|
|
{
|
|
ntru_init(1);
|
|
}
|
|
else
|
|
{
|
|
ntru_init(0);
|
|
}
|
|
int seed = 0;
|
|
randombytes(reinterpret_cast<unsigned char*>(&seed), sizeof(seed));
|
|
srand(seed);
|
|
}
|
|
|
|
std::optional<AlignedBuffer<32>>
|
|
CryptoLibSodium::maybe_decrypt_name(
|
|
std::string_view ciphertext, SymmNonce nounce, std::string_view name)
|
|
{
|
|
const auto payloadsize = ciphertext.size() - crypto_aead_xchacha20poly1305_ietf_ABYTES;
|
|
if (payloadsize != 32)
|
|
return {};
|
|
|
|
SharedSecret derivedKey{};
|
|
ShortHash namehash{};
|
|
const llarp_buffer_t namebuf(reinterpret_cast<const char*>(name.data()), name.size());
|
|
if (not shorthash(namehash, namebuf))
|
|
return {};
|
|
if (not hmac(derivedKey.data(), namebuf, namehash))
|
|
return {};
|
|
AlignedBuffer<32> result{};
|
|
if (crypto_aead_xchacha20poly1305_ietf_decrypt(
|
|
result.data(),
|
|
nullptr,
|
|
nullptr,
|
|
reinterpret_cast<const byte_t*>(ciphertext.data()),
|
|
ciphertext.size(),
|
|
nullptr,
|
|
0,
|
|
nounce.data(),
|
|
derivedKey.data())
|
|
== -1)
|
|
{
|
|
return {};
|
|
}
|
|
return result;
|
|
}
|
|
|
|
bool
|
|
CryptoLibSodium::xchacha20(
|
|
const llarp_buffer_t& buff, const SharedSecret& k, const TunnelNonce& n)
|
|
{
|
|
return crypto_stream_xchacha20_xor(buff.base, buff.base, buff.sz, n.data(), k.data()) == 0;
|
|
}
|
|
|
|
bool
|
|
CryptoLibSodium::xchacha20_alt(
|
|
const llarp_buffer_t& out, const llarp_buffer_t& in, const SharedSecret& k, const byte_t* n)
|
|
{
|
|
if (in.sz > out.sz)
|
|
return false;
|
|
return crypto_stream_xchacha20_xor(out.base, in.base, in.sz, n, k.data()) == 0;
|
|
}
|
|
|
|
bool
|
|
CryptoLibSodium::dh_client(
|
|
llarp::SharedSecret& shared, const PubKey& pk, const SecretKey& sk, const TunnelNonce& n)
|
|
{
|
|
return dh_client_priv(shared, pk, sk, n);
|
|
}
|
|
/// path dh relay side
|
|
bool
|
|
CryptoLibSodium::dh_server(
|
|
llarp::SharedSecret& shared, const PubKey& pk, const SecretKey& sk, const TunnelNonce& n)
|
|
{
|
|
return dh_server_priv(shared, pk, sk, n);
|
|
}
|
|
/// transport dh client side
|
|
bool
|
|
CryptoLibSodium::transport_dh_client(
|
|
llarp::SharedSecret& shared, const PubKey& pk, const SecretKey& sk, const TunnelNonce& n)
|
|
{
|
|
return dh_client_priv(shared, pk, sk, n);
|
|
}
|
|
/// transport dh server side
|
|
bool
|
|
CryptoLibSodium::transport_dh_server(
|
|
llarp::SharedSecret& shared, const PubKey& pk, const SecretKey& sk, const TunnelNonce& n)
|
|
{
|
|
return dh_server_priv(shared, pk, sk, n);
|
|
}
|
|
|
|
bool
|
|
CryptoLibSodium::shorthash(ShortHash& result, const llarp_buffer_t& buff)
|
|
{
|
|
return crypto_generichash_blake2b(
|
|
result.data(), ShortHash::SIZE, buff.base, buff.sz, nullptr, 0)
|
|
!= -1;
|
|
}
|
|
|
|
bool
|
|
CryptoLibSodium::hmac(byte_t* result, const llarp_buffer_t& buff, const SharedSecret& secret)
|
|
{
|
|
return crypto_generichash_blake2b(
|
|
result, HMACSIZE, buff.base, buff.sz, secret.data(), HMACSECSIZE)
|
|
!= -1;
|
|
}
|
|
|
|
static bool
|
|
hash(uint8_t* result, const llarp_buffer_t& buff)
|
|
{
|
|
return crypto_generichash_blake2b(result, HASHSIZE, buff.base, buff.sz, nullptr, 0) != -1;
|
|
}
|
|
|
|
bool
|
|
CryptoLibSodium::sign(Signature& sig, const SecretKey& secret, const llarp_buffer_t& buf)
|
|
{
|
|
return crypto_sign_detached(sig.data(), nullptr, buf.base, buf.sz, secret.data()) != -1;
|
|
}
|
|
|
|
bool
|
|
CryptoLibSodium::sign(Signature& sig, const PrivateKey& privkey, const llarp_buffer_t& buf)
|
|
{
|
|
PubKey pubkey;
|
|
|
|
privkey.toPublic(pubkey);
|
|
|
|
crypto_hash_sha512_state hs;
|
|
unsigned char nonce[64];
|
|
unsigned char hram[64];
|
|
unsigned char mulres[32];
|
|
|
|
// r = H(s || M) where here s is pseudorandom bytes typically generated as
|
|
// part of hashing the seed (i.e. [a,s] = H(k)), but for derived
|
|
// PrivateKeys will come from a hash of the root key's s concatenated with
|
|
// the derivation hash.
|
|
crypto_hash_sha512_init(&hs);
|
|
crypto_hash_sha512_update(&hs, privkey.signingHash(), 32);
|
|
crypto_hash_sha512_update(&hs, buf.base, buf.sz);
|
|
crypto_hash_sha512_final(&hs, nonce);
|
|
crypto_core_ed25519_scalar_reduce(nonce, nonce);
|
|
|
|
// copy pubkey into sig to make (for now) sig = (R || A)
|
|
memmove(sig.data() + 32, pubkey.data(), 32);
|
|
|
|
// R = r * B
|
|
crypto_scalarmult_ed25519_base_noclamp(sig.data(), nonce);
|
|
|
|
// hram = H(R || A || M)
|
|
crypto_hash_sha512_init(&hs);
|
|
crypto_hash_sha512_update(&hs, sig.data(), 64);
|
|
crypto_hash_sha512_update(&hs, buf.base, buf.sz);
|
|
crypto_hash_sha512_final(&hs, hram);
|
|
|
|
// S = r + H(R || A || M) * s, so sig = (R || S)
|
|
crypto_core_ed25519_scalar_reduce(hram, hram);
|
|
crypto_core_ed25519_scalar_mul(mulres, hram, privkey.data());
|
|
crypto_core_ed25519_scalar_add(sig.data() + 32, mulres, nonce);
|
|
|
|
sodium_memzero(nonce, sizeof nonce);
|
|
|
|
return true;
|
|
}
|
|
|
|
bool
|
|
CryptoLibSodium::verify(const PubKey& pub, const llarp_buffer_t& buf, const Signature& sig)
|
|
{
|
|
return crypto_sign_verify_detached(sig.data(), buf.base, buf.sz, pub.data()) != -1;
|
|
}
|
|
|
|
/// clamp a 32 byte ec point
|
|
static void
|
|
clamp_ed25519(byte_t* out)
|
|
{
|
|
out[0] &= 248;
|
|
out[31] &= 127;
|
|
out[31] |= 64;
|
|
}
|
|
|
|
template <typename K>
|
|
static K
|
|
clamp(const K& p)
|
|
{
|
|
K out = p;
|
|
clamp_ed25519(out);
|
|
return out;
|
|
}
|
|
|
|
template <typename K>
|
|
static bool
|
|
is_clamped(const K& key)
|
|
{
|
|
K other(key);
|
|
clamp_ed25519(other.data());
|
|
return other == key;
|
|
}
|
|
|
|
constexpr static char derived_key_hash_str[161] =
|
|
"just imagine what would happen if we all decided to understand. you "
|
|
"can't in the and by be or then before so just face it this text hurts "
|
|
"to read? lokinet yolo!";
|
|
|
|
template <typename K>
|
|
static bool
|
|
make_scalar(AlignedBuffer<32>& out, const K& k, uint64_t i)
|
|
{
|
|
// b = BLIND-STRING || k || i
|
|
std::array<byte_t, 160 + K::SIZE + sizeof(uint64_t)> buf;
|
|
std::copy(derived_key_hash_str, derived_key_hash_str + 160, buf.begin());
|
|
std::copy(k.begin(), k.end(), buf.begin() + 160);
|
|
htole64buf(buf.data() + 160 + K::SIZE, i);
|
|
// n = H(b)
|
|
// h = make_point(n)
|
|
ShortHash n;
|
|
return -1
|
|
!= crypto_generichash_blake2b(
|
|
n.data(), ShortHash::SIZE, buf.data(), buf.size(), nullptr, 0)
|
|
&& -1 != crypto_core_ed25519_from_uniform(out.data(), n.data());
|
|
}
|
|
|
|
static AlignedBuffer<32> zero;
|
|
|
|
bool
|
|
CryptoLibSodium::derive_subkey(
|
|
PubKey& out_pubkey,
|
|
const PubKey& root_pubkey,
|
|
uint64_t key_n,
|
|
const AlignedBuffer<32>* hash)
|
|
{
|
|
// scalar h = H( BLIND-STRING || root_pubkey || key_n )
|
|
AlignedBuffer<32> h;
|
|
if (hash)
|
|
h = *hash;
|
|
else if (not make_scalar(h, root_pubkey, key_n))
|
|
{
|
|
LogError("cannot make scalar");
|
|
return false;
|
|
}
|
|
|
|
return 0 == crypto_scalarmult_ed25519(out_pubkey.data(), h.data(), root_pubkey.data());
|
|
}
|
|
|
|
bool
|
|
CryptoLibSodium::derive_subkey_private(
|
|
PrivateKey& out_key,
|
|
const SecretKey& root_key,
|
|
uint64_t key_n,
|
|
const AlignedBuffer<32>* hash)
|
|
{
|
|
// Derives a private subkey from a root key.
|
|
//
|
|
// The basic idea is:
|
|
//
|
|
// h = H( BLIND-STRING || A || key_n )
|
|
// a - private key
|
|
// A = aB - public key
|
|
// s - signing hash
|
|
// a' = ah - derived private key
|
|
// A' = a'B = (ah)B - derived public key
|
|
// s' = H(h || s) - derived signing hash
|
|
//
|
|
// libsodium throws some wrenches in the mechanics which are a nuisance,
|
|
// the biggest of which is that sodium's secret key is *not* `a`; rather
|
|
// it is the seed. If you want to get the private key (i.e. "a"), you
|
|
// need to SHA-512 hash it and then clamp that.
|
|
//
|
|
// This also makes signature verification harder: we can't just use
|
|
// sodium's sign function because it wants to be given the seed rather
|
|
// than the private key, and moreover we can't actually *get* the seed to
|
|
// make libsodium happy because we only have `ah` above; thus we
|
|
// reimplemented most of sodium's detached signing function but without
|
|
// the hash step.
|
|
//
|
|
// Lastly, for the signing hash s', we need some value that is both
|
|
// different from the root s but also unknowable from the public key
|
|
// (since otherwise `r` in the signing function would be known), so we
|
|
// generate it from a hash of `h` and the root key's (psuedorandom)
|
|
// signing hash, `s`.
|
|
//
|
|
const auto root_pubkey = root_key.toPublic();
|
|
|
|
AlignedBuffer<32> h;
|
|
if (hash)
|
|
h = *hash;
|
|
else if (not make_scalar(h, root_pubkey, key_n))
|
|
{
|
|
LogError("cannot make scalar");
|
|
return false;
|
|
}
|
|
|
|
h[0] &= 248;
|
|
h[31] &= 63;
|
|
h[31] |= 64;
|
|
|
|
PrivateKey a;
|
|
if (!root_key.toPrivate(a))
|
|
return false;
|
|
|
|
// a' = ha
|
|
crypto_core_ed25519_scalar_mul(out_key.data(), h.data(), a.data());
|
|
|
|
// s' = H(h || s)
|
|
std::array<byte_t, 64> buf;
|
|
std::copy(h.begin(), h.end(), buf.begin());
|
|
std::copy(a.signingHash(), a.signingHash() + 32, buf.begin() + 32);
|
|
return -1
|
|
!= crypto_generichash_blake2b(
|
|
out_key.signingHash(), 32, buf.data(), buf.size(), nullptr, 0);
|
|
|
|
return true;
|
|
}
|
|
|
|
bool
|
|
CryptoLibSodium::seed_to_secretkey(llarp::SecretKey& secret, const llarp::IdentitySecret& seed)
|
|
{
|
|
return crypto_sign_ed25519_seed_keypair(secret.data() + 32, secret.data(), seed.data()) != -1;
|
|
}
|
|
void
|
|
CryptoLibSodium::randomize(const llarp_buffer_t& buff)
|
|
{
|
|
randombytes((unsigned char*)buff.base, buff.sz);
|
|
}
|
|
|
|
void
|
|
CryptoLibSodium::randbytes(byte_t* ptr, size_t sz)
|
|
{
|
|
randombytes((unsigned char*)ptr, sz);
|
|
}
|
|
|
|
void
|
|
CryptoLibSodium::identity_keygen(llarp::SecretKey& keys)
|
|
{
|
|
PubKey pk;
|
|
int result = crypto_sign_keypair(pk.data(), keys.data());
|
|
assert(result != -1);
|
|
const PubKey sk_pk = keys.toPublic();
|
|
assert(pk == sk_pk);
|
|
(void)result;
|
|
(void)sk_pk;
|
|
|
|
// encryption_keygen(keys);
|
|
}
|
|
|
|
bool
|
|
CryptoLibSodium::check_identity_privkey(const llarp::SecretKey& keys)
|
|
{
|
|
AlignedBuffer<crypto_sign_SEEDBYTES> seed;
|
|
llarp::PubKey pk;
|
|
llarp::SecretKey sk;
|
|
if (crypto_sign_ed25519_sk_to_seed(seed.data(), keys.data()) == -1)
|
|
return false;
|
|
if (crypto_sign_seed_keypair(pk.data(), sk.data(), seed.data()) == -1)
|
|
return false;
|
|
return keys.toPublic() == pk && sk == keys;
|
|
}
|
|
|
|
void
|
|
CryptoLibSodium::encryption_keygen(llarp::SecretKey& keys)
|
|
{
|
|
auto d = keys.data();
|
|
randbytes(d, 32);
|
|
crypto_scalarmult_curve25519_base(d + 32, d);
|
|
}
|
|
|
|
bool
|
|
CryptoLibSodium::pqe_encrypt(
|
|
PQCipherBlock& ciphertext, SharedSecret& sharedkey, const PQPubKey& pubkey)
|
|
{
|
|
return crypto_kem_enc(ciphertext.data(), sharedkey.data(), pubkey.data()) != -1;
|
|
}
|
|
bool
|
|
CryptoLibSodium::pqe_decrypt(
|
|
const PQCipherBlock& ciphertext, SharedSecret& sharedkey, const byte_t* secretkey)
|
|
{
|
|
return crypto_kem_dec(sharedkey.data(), ciphertext.data(), secretkey) != -1;
|
|
}
|
|
|
|
void
|
|
CryptoLibSodium::pqe_keygen(PQKeyPair& keypair)
|
|
{
|
|
auto d = keypair.data();
|
|
crypto_kem_keypair(d + PQ_SECRETKEYSIZE, d);
|
|
}
|
|
} // namespace sodium
|
|
|
|
const byte_t*
|
|
seckey_topublic(const SecretKey& sec)
|
|
{
|
|
return sec.data() + 32;
|
|
}
|
|
|
|
const byte_t*
|
|
pq_keypair_to_public(const PQKeyPair& k)
|
|
{
|
|
return k.data() + PQ_SECRETKEYSIZE;
|
|
}
|
|
|
|
const byte_t*
|
|
pq_keypair_to_secret(const PQKeyPair& k)
|
|
{
|
|
return k.data();
|
|
}
|
|
|
|
uint64_t
|
|
randint()
|
|
{
|
|
uint64_t i;
|
|
randombytes((byte_t*)&i, sizeof(i));
|
|
return i;
|
|
}
|
|
|
|
} // namespace llarp
|