def crypto_lock(key, nonce, msg, ad=b''):
"""
:returns: (bytes(mac), bytes(ciphertext))
"""
ensure_length('key', key, 32)
ensure_length('nonce', nonce, 24)
key = ffi.from_buffer('uint8_t[32]', key)
nonce = ffi.from_buffer('uint8_t[24]', nonce)
mac = ffi.new('uint8_t[16]')
ct = ffi.new('uint8_t[]', len(msg))
msg = ffi.from_buffer('uint8_t[]', msg)
ad = ffi.from_buffer('uint8_t[]', ad)
lib.crypto_lock_aead(
mac,
ct,
key,
nonce,
ad,
len(ad),
msg,
len(msg),
)
return bytes(mac), bytes(ct)
def crypto_from_eddsa_public(eddsa):
ensure_length('eddsa', eddsa, 32)
eddsa = ffi.from_buffer('uint8_t[32]', eddsa)
x25519 = ffi.new('uint8_t[32]')
lib.crypto_from_eddsa_public(x25519, eddsa)
return bytes(x25519)
def crypto_sign_public_key(secret_key):
ensure_length('secret_key', secret_key, 32)
sk = ffi.from_buffer('uint8_t[32]', secret_key)
pk = ffi.new('uint8_t[32]')
lib.crypto_sign_public_key(pk, sk)
return bytes(pk)
def crypto_x25519_public_key(your_secret_key):
ensure_length('your_secret_key', your_secret_key, 32)
sk = ffi.from_buffer('uint8_t[32]', your_secret_key)
pk = ffi.new('uint8_t[32]')
lib.crypto_x25519_public_key(pk, sk)
return bytes(pk)
def crypto_verify16(a, b):
ensure_length('a', a, 16)
ensure_length('b', b, 16)
return lib.crypto_verify16(
ffi.from_buffer('uint8_t[16]', a),
ffi.from_buffer('uint8_t[16]', b),
) == 0
def crypto_verify64(a, b):
ensure_length('a', a, 64)
ensure_length('b', b, 64)
return lib.crypto_verify64(
ffi.from_buffer('uint8_t[64]', a),
ffi.from_buffer('uint8_t[64]', b),
) == 0
def crypto_verify32(a, b):
ensure_length('a', a, 32)
ensure_length('b', b, 32)
return lib.crypto_verify32(
ffi.from_buffer('uint8_t[32]', a),
ffi.from_buffer('uint8_t[32]', b),
) == 0
def crypto_check(sig, public_key, msg):
ensure_length('sig', sig, 64)
ensure_length('public_key', public_key, 32)
sig = ffi.from_buffer('uint8_t[64]', sig)
pk = ffi.from_buffer('uint8_t[32]', public_key)
msg = ffi.from_buffer('uint8_t[]', msg)
rv = lib.crypto_check(sig, pk, msg, len(msg))
return rv == 0
def crypto_key_exchange(your_secret_key, their_public_key):
ensure_length('your_secret_key', your_secret_key, 32)
ensure_length('their_public_key', their_public_key, 32)
sk = ffi.from_buffer('uint8_t[32]', your_secret_key)
pk = ffi.from_buffer('uint8_t[32]', their_public_key)
shared = ffi.new('uint8_t[32]')
lib.crypto_key_exchange(shared, sk, pk)
return bytes(shared)
def crypto_sign(secret_key, msg):
ensure_length('secret_key', secret_key, 32)
sk = ffi.from_buffer('uint8_t[32]', secret_key)
msg = ffi.from_buffer('uint8_t[]', msg)
sig = ffi.new('uint8_t[64]')
pk = ffi.new('uint8_t[32]')
lib.crypto_sign_public_key(pk, secret_key)
lib.crypto_sign(sig, sk, pk, msg, len(msg))
lib.crypto_wipe(pk, 32)
return bytes(sig)
def crypto_unlock(key, mac, nonce, ciphertext, ad=b''):
"""
:returns: None or bytes(msg)
"""
ensure_length('key', key, 32)
ensure_length('mac', mac, 16)
ensure_length('nonce', nonce, 24)
key = ffi.from_buffer('uint8_t[32]', key)
mac = ffi.from_buffer('uint8_t[16]', mac)
nonce = ffi.from_buffer('uint8_t[24]', nonce)
ct = ffi.from_buffer('uint8_t[]', ciphertext)
ad = ffi.from_buffer('uint8_t[]', ad)
pt = ffi.new('uint8_t[]', len(ciphertext))
rv = lib.crypto_unlock_aead(
pt,
key,
nonce,
mac,
ad,
len(ad),
ct,
len(ct),
)
if rv != 0:
return None
return bytes(pt)