Files
concrete/compiler/lib/ClientLib/KeySet.cpp

372 lines
14 KiB
C++

// Part of the Concrete Compiler Project, under the BSD3 License with Zama
// Exceptions. See
// https://github.com/zama-ai/homomorphizer/blob/master/LICENSE.txt for license
// information.
#include "concretelang/ClientLib/KeySet.h"
#include "concretelang/Support/Error.h"
#define CAPI_ERR_TO_LLVM_ERROR(s, msg) \
{ \
int err; \
s; \
if (err != 0) { \
return llvm::make_error<llvm::StringError>( \
msg, llvm::inconvertibleErrorCode()); \
} \
}
namespace mlir {
namespace concretelang {
KeySet::~KeySet() {
int err;
for (auto it : secretKeys) {
free_lwe_secret_key_u64(&err, it.second.second);
}
for (auto it : bootstrapKeys) {
free_lwe_bootstrap_key_u64(&err, it.second.second);
}
for (auto it : keyswitchKeys) {
free_lwe_keyswitch_key_u64(&err, it.second.second);
}
free_encryption_generator(&err, encryptionRandomGenerator);
}
llvm::Expected<std::unique_ptr<KeySet>>
KeySet::generate(ClientParameters &params, uint64_t seed_msb,
uint64_t seed_lsb) {
auto keySet = uninitialized();
if (auto error = keySet->generateKeysFromParams(params, seed_msb, seed_lsb)) {
return std::move(error);
}
if (auto error =
keySet->setupEncryptionMaterial(params, seed_msb, seed_lsb)) {
return std::move(error);
}
return std::move(keySet);
}
std::unique_ptr<KeySet> KeySet::uninitialized() {
return std::make_unique<KeySet>();
}
llvm::Error KeySet::setupEncryptionMaterial(ClientParameters &params,
uint64_t seed_msb,
uint64_t seed_lsb) {
// Set inputs and outputs LWE secret keys
{
for (auto param : params.inputs) {
LweSecretKeyParam secretKeyParam = {0};
LweSecretKey_u64 *secretKey = nullptr;
if (param.encryption.hasValue()) {
auto inputSk = this->secretKeys.find(param.encryption->secretKeyID);
if (inputSk == this->secretKeys.end()) {
return llvm::make_error<llvm::StringError>(
"input encryption secret key (" + param.encryption->secretKeyID +
") does not exist ",
llvm::inconvertibleErrorCode());
}
secretKeyParam = inputSk->second.first;
secretKey = inputSk->second.second;
}
std::tuple<CircuitGate, LweSecretKeyParam, LweSecretKey_u64 *> input = {
param, secretKeyParam, secretKey};
this->inputs.push_back(input);
}
for (auto param : params.outputs) {
LweSecretKeyParam secretKeyParam = {0};
LweSecretKey_u64 *secretKey = nullptr;
if (param.encryption.hasValue()) {
auto outputSk = this->secretKeys.find(param.encryption->secretKeyID);
if (outputSk == this->secretKeys.end()) {
return llvm::make_error<llvm::StringError>(
"cannot find output key to generate bootstrap key",
llvm::inconvertibleErrorCode());
}
secretKeyParam = outputSk->second.first;
secretKey = outputSk->second.second;
}
std::tuple<CircuitGate, LweSecretKeyParam, LweSecretKey_u64 *> output = {
param, secretKeyParam, secretKey};
this->outputs.push_back(output);
}
}
int err;
CAPI_ERR_TO_LLVM_ERROR(
this->encryptionRandomGenerator =
allocate_encryption_generator(&err, seed_msb, seed_lsb),
"cannot allocate encryption generator");
return llvm::Error::success();
}
llvm::Error KeySet::generateKeysFromParams(ClientParameters &params,
uint64_t seed_msb,
uint64_t seed_lsb) {
{
// Generate LWE secret keys
SecretRandomGenerator *generator;
CAPI_ERR_TO_LLVM_ERROR(
generator = allocate_secret_generator(&err, seed_msb, seed_lsb),
"cannot allocate random generator");
for (auto secretKeyParam : params.secretKeys) {
auto e = this->generateSecretKey(secretKeyParam.first,
secretKeyParam.second, generator);
if (e) {
return std::move(e);
}
}
CAPI_ERR_TO_LLVM_ERROR(free_secret_generator(&err, generator),
"cannot free random generator");
}
// Allocate the encryption random generator
CAPI_ERR_TO_LLVM_ERROR(
this->encryptionRandomGenerator =
allocate_encryption_generator(&err, seed_msb, seed_lsb),
"cannot allocate encryption generator");
// Generate bootstrap and keyswitch keys
{
for (auto bootstrapKeyParam : params.bootstrapKeys) {
auto e = this->generateBootstrapKey(bootstrapKeyParam.first,
bootstrapKeyParam.second,
this->encryptionRandomGenerator);
if (e) {
return std::move(e);
}
}
for (auto keyswitchParam : params.keyswitchKeys) {
auto e = this->generateKeyswitchKey(keyswitchParam.first,
keyswitchParam.second,
this->encryptionRandomGenerator);
if (e) {
return std::move(e);
}
}
}
return llvm::Error::success();
}
void KeySet::setKeys(
std::map<LweSecretKeyID, std::pair<LweSecretKeyParam, LweSecretKey_u64 *>>
secretKeys,
std::map<LweSecretKeyID,
std::pair<BootstrapKeyParam, LweBootstrapKey_u64 *>>
bootstrapKeys,
std::map<LweSecretKeyID,
std::pair<KeyswitchKeyParam, LweKeyswitchKey_u64 *>>
keyswitchKeys) {
this->secretKeys = secretKeys;
this->bootstrapKeys = bootstrapKeys;
this->keyswitchKeys = keyswitchKeys;
}
llvm::Error KeySet::generateSecretKey(LweSecretKeyID id,
LweSecretKeyParam param,
SecretRandomGenerator *generator) {
LweSecretKey_u64 *sk;
CAPI_ERR_TO_LLVM_ERROR(
sk = allocate_lwe_secret_key_u64(&err, {param.size + 1}),
"cannot allocate secret key");
CAPI_ERR_TO_LLVM_ERROR(fill_lwe_secret_key_u64(&err, sk, generator),
"cannot fill secret key with random generator");
secretKeys[id] = {param, sk};
return llvm::Error::success();
}
llvm::Error KeySet::generateBootstrapKey(BootstrapKeyID id,
BootstrapKeyParam param,
EncryptionRandomGenerator *generator) {
// Finding input and output secretKeys
auto inputSk = secretKeys.find(param.inputSecretKeyID);
if (inputSk == secretKeys.end()) {
return llvm::make_error<llvm::StringError>(
"cannot find input key to generate bootstrap key",
llvm::inconvertibleErrorCode());
}
auto outputSk = secretKeys.find(param.outputSecretKeyID);
if (outputSk == secretKeys.end()) {
return llvm::make_error<llvm::StringError>(
"cannot find output key to generate bootstrap key",
llvm::inconvertibleErrorCode());
}
// Allocate the bootstrap key
LweBootstrapKey_u64 *bsk;
uint64_t total_dimension = outputSk->second.first.size;
assert(total_dimension % param.glweDimension == 0);
uint64_t polynomialSize = total_dimension / param.glweDimension;
CAPI_ERR_TO_LLVM_ERROR(
bsk = allocate_lwe_bootstrap_key_u64(
&err, {param.level}, {param.baseLog}, {param.glweDimension + 1},
{inputSk->second.first.size + 1}, {polynomialSize}),
"cannot allocate bootstrap key");
// Store the bootstrap key
bootstrapKeys[id] = {param, bsk};
// Convert the output lwe key to glwe key
GlweSecretKey_u64 *glwe_sk;
CAPI_ERR_TO_LLVM_ERROR(
glwe_sk = allocate_glwe_secret_key_u64(&err, {param.glweDimension + 1},
{polynomialSize}),
"cannot allocate glwe key for initiliazation of bootstrap key");
CAPI_ERR_TO_LLVM_ERROR(fill_glwe_secret_key_with_lwe_secret_key_u64(
&err, glwe_sk, outputSk->second.second),
"cannot fill glwe key with big key");
// Initialize the bootstrap key
CAPI_ERR_TO_LLVM_ERROR(
fill_lwe_bootstrap_key_u64(&err, bsk, inputSk->second.second, glwe_sk,
generator, {param.variance}),
"cannot fill bootstrap key");
CAPI_ERR_TO_LLVM_ERROR(
free_glwe_secret_key_u64(&err, glwe_sk),
"cannot free glwe key for initiliazation of bootstrap key")
return llvm::Error::success();
}
llvm::Error KeySet::generateKeyswitchKey(KeyswitchKeyID id,
KeyswitchKeyParam param,
EncryptionRandomGenerator *generator) {
// Finding input and output secretKeys
auto inputSk = secretKeys.find(param.inputSecretKeyID);
if (inputSk == secretKeys.end()) {
return llvm::make_error<llvm::StringError>(
"cannot find input key to generate keyswitch key",
llvm::inconvertibleErrorCode());
}
auto outputSk = secretKeys.find(param.outputSecretKeyID);
if (outputSk == secretKeys.end()) {
return llvm::make_error<llvm::StringError>(
"cannot find input key to generate keyswitch key",
llvm::inconvertibleErrorCode());
}
// Allocate the keyswitch key
LweKeyswitchKey_u64 *ksk;
CAPI_ERR_TO_LLVM_ERROR(
ksk = allocate_lwe_keyswitch_key_u64(&err, {param.level}, {param.baseLog},
{inputSk->second.first.size + 1},
{outputSk->second.first.size + 1}),
"cannot allocate keyswitch key");
// Store the keyswitch key
keyswitchKeys[id] = {param, ksk};
// Initialize the keyswitch key
CAPI_ERR_TO_LLVM_ERROR(
fill_lwe_keyswitch_key_u64(&err, ksk, inputSk->second.second,
outputSk->second.second, generator,
{param.variance}),
"cannot fill bootsrap key");
return llvm::Error::success();
}
llvm::Error KeySet::allocate_lwe(size_t argPos,
LweCiphertext_u64 **ciphertext) {
if (argPos >= inputs.size()) {
return llvm::make_error<llvm::StringError>(
"allocate_lwe position of argument is too high",
llvm::inconvertibleErrorCode());
}
auto inputSk = inputs[argPos];
CAPI_ERR_TO_LLVM_ERROR(*ciphertext = allocate_lwe_ciphertext_u64(
&err, {std::get<1>(inputSk).size + 1}),
"cannot allocate ciphertext");
return llvm::Error::success();
}
bool KeySet::isInputEncrypted(size_t argPos) {
return argPos < inputs.size() &&
std::get<0>(inputs[argPos]).encryption.hasValue();
}
bool KeySet::isOutputEncrypted(size_t argPos) {
return argPos < outputs.size() &&
std::get<0>(outputs[argPos]).encryption.hasValue();
}
llvm::Error KeySet::encrypt_lwe(size_t argPos, LweCiphertext_u64 *ciphertext,
uint64_t input) {
if (argPos >= inputs.size()) {
return llvm::make_error<llvm::StringError>(
"encrypt_lwe position of argument is too high",
llvm::inconvertibleErrorCode());
}
auto inputSk = inputs[argPos];
if (!std::get<0>(inputSk).encryption.hasValue()) {
return llvm::make_error<llvm::StringError>(
"encrypt_lwe the positional argument is not encrypted",
llvm::inconvertibleErrorCode());
}
// Encode - TODO we could check if the input value is in the right range
Plaintext_u64 plaintext = {
input << (64 -
(std::get<0>(inputSk).encryption->encoding.precision + 1))};
// Encrypt
CAPI_ERR_TO_LLVM_ERROR(
encrypt_lwe_u64(&err, std::get<2>(inputSk), ciphertext, plaintext,
encryptionRandomGenerator,
{std::get<0>(inputSk).encryption->variance}),
"cannot encrypt");
return llvm::Error::success();
}
llvm::Error KeySet::decrypt_lwe(size_t argPos, LweCiphertext_u64 *ciphertext,
uint64_t &output) {
if (argPos >= outputs.size()) {
return llvm::make_error<llvm::StringError>(
"decrypt_lwe: position of argument is too high",
llvm::inconvertibleErrorCode());
}
auto outputSk = outputs[argPos];
if (!std::get<0>(outputSk).encryption.hasValue()) {
return llvm::make_error<llvm::StringError>(
"decrypt_lwe: the positional argument is not encrypted",
llvm::inconvertibleErrorCode());
}
// Decrypt
Plaintext_u64 plaintext = {0};
CAPI_ERR_TO_LLVM_ERROR(
decrypt_lwe_u64(&err, std::get<2>(outputSk), ciphertext, &plaintext),
"cannot decrypt");
// Decode
size_t precision = std::get<0>(outputSk).encryption->encoding.precision;
output = plaintext._0 >> (64 - precision - 2);
size_t carry = output % 2;
output = ((output >> 1) + carry) % (1 << (precision + 1));
return llvm::Error::success();
}
const std::map<LweSecretKeyID, std::pair<LweSecretKeyParam, LweSecretKey_u64 *>>
&KeySet::getSecretKeys() {
return secretKeys;
}
const std::map<LweSecretKeyID,
std::pair<BootstrapKeyParam, LweBootstrapKey_u64 *>> &
KeySet::getBootstrapKeys() {
return bootstrapKeys;
}
const std::map<LweSecretKeyID,
std::pair<KeyswitchKeyParam, LweKeyswitchKey_u64 *>> &
KeySet::getKeyswitchKeys() {
return keyswitchKeys;
}
} // namespace concretelang
} // namespace mlir