/// <summary>
/// Encrypts a zero plaintext with the secret key and stores the result in
/// destination.
/// </summary>
/// <remarks>
/// The encryption parameters for the resulting ciphertext correspond to the
/// highest (data) level in the modulus switching chain. Dynamic memory
/// allocations in the process are allocated from the memory pool pointed to
/// by the given MemoryPoolHandle.
///
/// Half of the polynomials in relinearization keys are randomly generated
/// and are replaced with the seed used to compress output size. The output
/// is in binary format and not human-readable. The output stream must have
/// the "binary" flag set.
/// </remarks>
/// <param name="stream">The stream to save the Ciphertext to</param>
/// <param name="comprMode">The desired compression mode</param>
/// <param name="pool">The MemoryPoolHandle pointing to a valid memory
/// pool</param>
/// <exception cref="ArgumentNullException">if stream is null</exception>
/// <exception cref="InvalidOperationException">if a secret key is not
/// set</exception>
/// <exception cref="ArgumentException">if the stream is closed or does not
/// support writing</exception>
/// <exception cref="IOException">if I/O operations failed</exception>
/// <exception cref="InvalidOperationException">if compression mode is not
/// supported, or if compression failed</exception>
/// <exception cref="ArgumentException">if pool is uninitialized</exception>
public long EncryptZeroSymmetricSave(
Stream stream, ComprModeType?comprMode = null,
MemoryPoolHandle pool = null)
{
if (null == stream)
{
throw new ArgumentNullException(nameof(stream));
}
comprMode = comprMode ?? Serialization.ComprModeDefault;
if (!Serialization.IsSupportedComprMode(comprMode.Value))
{
throw new InvalidOperationException("Unsupported compression mode");
}
IntPtr poolHandle = pool?.NativePtr ?? IntPtr.Zero;
using (Ciphertext destination = new Ciphertext(pool))
{
NativeMethods.Encryptor_EncryptZeroSymmetric2(
NativePtr, true, destination.NativePtr, poolHandle);
return(destination.Save(stream, comprMode));
}
}
/// <summary>
/// Encrypts a zero plaintext with the public key and returns the ciphertext
/// as a serializable object.
/// </summary>
/// <remarks>
/// <para>
/// Encrypts a zero plaintext with the public key and returns the ciphertext
/// as a serializable object.
/// </para>
/// <para>
/// The encryption parameters for the resulting ciphertext correspond to the
/// highest (data) level in the modulus switching chain. Dynamic memory
/// allocations in the process are allocated from the memory pool pointed to
/// by the given MemoryPoolHandle.
/// </para>
/// </remarks>
/// <param name="pool">The MemoryPoolHandle pointing to a valid memory
/// pool</param>
/// <exception cref="InvalidOperationException">if a public key is not
/// set</exception>
/// <exception cref="ArgumentException">if pool is uninitialized</exception>
public Serializable <Ciphertext> EncryptZero(MemoryPoolHandle pool = null)
{
Ciphertext destination = new Ciphertext();
EncryptZero(destination, pool);
return(new Serializable <Ciphertext>(destination));
}
/// <summary>
/// Loads a RelinKeys from an input stream overwriting the current RelinKeys.
/// No checking of the validity of the RelinKeys data against encryption
/// parameters is performed. This function should not be used unless the
/// RelinKeys comes from a fully trusted source.
/// </summary>
/// <param name="stream">The stream to load the RelinKeys from</param>
/// <exception cref="ArgumentNullException">if stream is null</exception>
/// <exception cref="ArgumentException">if valid RelinKeys could not be read
/// from stream</exception>
public void UnsafeLoad(Stream stream)
{
if (null == stream)
{
throw new ArgumentNullException(nameof(stream));
}
try
{
// Read the ParmsId
ParmsId parmsId = new ParmsId();
parmsId.Load(stream);
ParmsId = parmsId;
using (BinaryReader reader = new BinaryReader(stream, Encoding.UTF8, leaveOpen: true))
{
// Read the decomposition bit count
int dbc = reader.ReadInt32();
DecompositionBitCount = dbc;
// Read the size
ulong size = reader.ReadUInt64();
// Clear current data and reserve new size
NativeMethods.RelinKeys_ClearDataAndReserve(NativePtr, size);
// Read all lists
for (ulong i = 0; i < size; i++)
{
// Read size of second list
ulong keySize = reader.ReadUInt64();
List <Ciphertext> ciphers = new List <Ciphertext>((int)keySize);
// Load all ciphertexts
for (ulong j = 0; j < keySize; j++)
{
Ciphertext cipher = new Ciphertext();
cipher.UnsafeLoad(reader.BaseStream);
ciphers.Add(cipher);
}
IntPtr[] pointers = ciphers.Select(c =>
{
return(c.NativePtr);
}).ToArray();
NativeMethods.RelinKeys_AddKeyList(NativePtr, (ulong)pointers.LongLength, pointers);
}
}
}
catch (EndOfStreamException ex)
{
throw new ArgumentException("Stream ended unexpectedly", ex);
}
catch (IOException ex)
{
throw new ArgumentException("Error reading keys", ex);
}
}
/// <summary>
/// Copies a given ciphertext to the current one.
/// </summary>
///
/// <param name="assign">The ciphertext to copy from</param>
/// <exception cref="ArgumentNullException">if assign is null</exception>
public void Set(Ciphertext assign)
{
if (null == assign)
{
throw new ArgumentNullException(nameof(assign));
}
NativeMethods.Ciphertext_Set(NativePtr, assign.NativePtr);
}
/// <summary>
/// Constructs a new ciphertext by copying a given one.
/// </summary>
/// <param name="copy">The ciphertext to copy from</param>
/// <param name="pool">The MemoryPoolHandle pointing to a valid memory pool</param>
/// <exception cref="ArgumentNullException">if either copy or pool are null</exception>
/// <exception cref="ArgumentException">if pool is uninitialized</exception>
public Ciphertext(Ciphertext copy, MemoryPoolHandle pool) : this(pool)
{
if (null == copy)
{
throw new ArgumentNullException(nameof(copy));
}
Set(copy);
}
/// <summary>
/// Encrypts a zero plaintext with the secret key and returns the ciphertext
/// as a serializable object.
/// </summary>
/// <remarks>
/// <para>
/// Encrypts a zero plaintext with the secret key and returns the ciphertext
/// as a serializable object.
/// </para>
/// <para>
/// Half of the ciphertext data is pseudo-randomly generated from a seed to
/// reduce the object size. The resulting serializable object cannot be used
/// directly and is meant to be serialized for the size reduction to have an
/// impact.
/// </para>
/// <para>
/// The encryption parameters for the resulting ciphertext correspond to the
/// highest (data) level in the modulus switching chain. Dynamic memory
/// allocations in the process are allocated from the memory pool pointed to
/// by the given MemoryPoolHandle.
/// </para>
/// </remarks>
/// <param name="pool">The MemoryPoolHandle pointing to a valid memory
/// pool</param>
/// <exception cref="InvalidOperationException">if a secret key is not
/// set</exception>
/// <exception cref="ArgumentException">if pool is uninitialized</exception>
public Serializable <Ciphertext> EncryptZeroSymmetric(MemoryPoolHandle pool = null)
{
IntPtr poolHandle = pool?.NativePtr ?? IntPtr.Zero;
Ciphertext destination = new Ciphertext();
NativeMethods.Encryptor_EncryptZeroSymmetric2(
NativePtr, true, destination.NativePtr, poolHandle);
return(new Serializable <Ciphertext>(destination));
}
/// <summary>
/// Computes the invariant noise budget (in bits) of a ciphertext. The invariant noise
/// budget measures the amount of room there is for the noise to grow while ensuring
/// correct decryptions. Dynamic memory allocations in the process are allocated from
/// the memory pool pointed to by the given MemoryPoolHandle. This function works only
/// with the BFV scheme.
/// </summary>
/// <remarks>
/// <para>
/// Invariant Noise Budget
/// The invariant noise polynomial of a ciphertext is a rational coefficient polynomial,
/// such that a ciphertext decrypts correctly as long as the coefficients of the invariant
/// noise polynomial are of absolute value less than 1/2. Thus, we call the infinity-norm
/// of the invariant noise polynomial the invariant noise, and for correct decryption require
/// it to be less than 1/2. If v denotes the invariant noise, we define the invariant noise
/// budget as -log2(2v). Thus, the invariant noise budget starts from some initial value,
/// which depends on the encryption parameters, and decreases when computations are performed.
/// When the budget reaches zero, the ciphertext becomes too noisy to decrypt correctly.
/// </para>
/// </remarks>
/// <param name="encrypted">The ciphertext</param>
/// <exception cref="ArgumentNullException">if encrypted is null</exception>
/// <exception cref="ArgumentException">if the scheme is not BFV or BGV</exception>
/// <exception cref="ArgumentException">if encrypted is not valid for the encryption parameters</exception>
/// <exception cref="ArgumentException">if encrypted is in NTT form</exception>
/// <exception cref="ArgumentException">if pool is uninitialized</exception>
public int InvariantNoiseBudget(Ciphertext encrypted)
{
if (null == encrypted)
{
throw new ArgumentNullException(nameof(encrypted));
}
NativeMethods.Decryptor_InvariantNoiseBudget(NativePtr, encrypted.NativePtr, out int result);
return(result);
}
/// <summary>
/// Constructs a new ciphertext by copying a given one.
/// </summary>
/// <param name="copy">The ciphertext to copy from</param>
/// <exception cref="ArgumentNullException">if copy is null</exception>
public Ciphertext(Ciphertext copy)
{
if (null == copy)
{
throw new ArgumentNullException(nameof(copy));
}
NativeMethods.Ciphertext_Create2(copy.NativePtr, out IntPtr ptr);
NativePtr = ptr;
}
/// <summary>
/// Encrypts a zero plaintext with the public key and stores the result in
/// destination.
/// </summary>
/// <remarks>
/// <para>
/// Encrypts a zero plaintext with the public key and stores the result in
/// destination.
/// </para>
/// <para>
/// The encryption parameters for the resulting ciphertext correspond to the
/// highest (data) level in the modulus switching chain. Dynamic memory allocations
/// in the process are allocated from the memory pool pointed to by the given
/// MemoryPoolHandle.
/// </para>
/// </remarks>
/// <param name="destination">The ciphertext to overwrite with the encrypted
/// plaintext</param>
/// <param name="pool">The MemoryPoolHandle pointing to a valid memory pool</param>
/// <exception cref="ArgumentNullException">if destination is null</exception>
/// <exception cref="InvalidOperationException">if a public key is not set</exception>
/// <exception cref="ArgumentException">if pool is uninitialized</exception>
public void EncryptZero(Ciphertext destination, MemoryPoolHandle pool = null)
{
if (null == destination)
{
throw new ArgumentNullException(nameof(destination));
}
IntPtr poolHandle = pool?.NativePtr ?? IntPtr.Zero;
NativeMethods.Encryptor_EncryptZero2(NativePtr, destination.NativePtr, poolHandle);
}
/// <summary>
/// Decrypts a Ciphertext and stores the result in the destination parameter. Dynamic
/// memory allocations in the process are allocated from the memory pool pointed to by
/// the given MemoryPoolHandle.
/// </summary>
/// <param name="encrypted">The ciphertext to decrypt</param>
/// <param name="destination">The plaintext to overwrite with the decrypted ciphertext</param>
/// <exception cref="ArgumentNullException">if either encrypted or destination are null</exception>
/// <exception cref="ArgumentException">if encrypted is not valid for the encryption parameters</exception>
/// <exception cref="ArgumentException">if encrypted is not in the default NTT form</exception>
/// <exception cref="ArgumentException">if pool is uninitialized</exception>
public void Decrypt(Ciphertext encrypted, Plaintext destination)
{
if (null == encrypted)
{
throw new ArgumentNullException(nameof(encrypted));
}
if (null == destination)
{
throw new ArgumentNullException(nameof(destination));
}
NativeMethods.Decryptor_Decrypt(NativePtr, encrypted.NativePtr, destination.NativePtr);
}
/// <summary>
/// Check whether the given ciphertext is valid for a given SEALContext. If the
/// given SEALContext is not set, the encryption parameters are invalid, or the
/// ciphertext data does not match the SEALContext, this function returns false.
/// Otherwise, returns true.
/// </summary>
/// <param name="ciphertext">The ciphertext to check</param>
/// <param name="context">The SEALContext</param>
/// <exception cref="ArgumentNullException">if either ciphertext or context is null</exception>
public static bool IsValidFor(Ciphertext ciphertext, SEALContext context)
{
if (null == ciphertext)
{
throw new ArgumentNullException(nameof(ciphertext));
}
if (null == context)
{
throw new ArgumentNullException(nameof(context));
}
NativeMethods.ValCheck_Ciphertext_IsValidFor(ciphertext.NativePtr, context.NativePtr, out bool result);
return(result);
}
/// <summary>
/// Encrypts a zero plaintext with the secret key and stores the result in destination.
/// </summary>
/// <remarks>
/// The encryption parameters for the resulting ciphertext correspond to the
/// highest (data) level in the modulus switching chain. Dynamic memory allocations in
/// the process are allocated from the memory pool pointed to by the given MemoryPoolHandle.
///
/// Half of the polynomials in relinearization keys are randomly generated
/// and are replaced with the seed used to compress output size. The output
/// is in binary format and not human-readable. The output stream must have
/// the "binary" flag set.
/// </remarks>
/// <param name="stream">The stream to save the Ciphertext to</param>
/// <param name="comprMode">The desired compression mode</param>
/// <param name="pool">The MemoryPoolHandle pointing to a valid memory pool</param>
/// <exception cref="ArgumentNullException">if stream is null</exception>
/// <exception cref="ArgumentException">if pool is uninitialized</exception>
public long EncryptZeroSymmetricSave(Stream stream, ComprModeType?comprMode = null, MemoryPoolHandle pool = null)
{
if (null == stream)
{
throw new ArgumentNullException(nameof(stream));
}
IntPtr poolHandle = pool?.NativePtr ?? IntPtr.Zero;
using (Ciphertext destination = new Ciphertext(pool))
{
NativeMethods.Encryptor_EncryptZeroSymmetric2(NativePtr, true, destination.NativePtr, poolHandle);
return(destination.Save(stream, comprMode));
}
}
/// <summary>
/// Encrypts a zero plaintext with the secret key and stores the result in destination.
/// </summary>
/// <remarks>
/// The encryption parameters for the resulting ciphertext correspond to the given
/// parms_id. Dynamic memory allocations in the process are allocated from the memory
/// pool pointed to by the given MemoryPoolHandle.
/// </remarks>
/// <param name="parmsId">The ParmsId for the resulting ciphertext</param>
/// <param name="destination">The ciphertext to overwrite with the encrypted plaintext</param>
/// <param name="pool">The MemoryPoolHandle pointing to a valid memory pool</param>
/// <exception cref="ArgumentNullException">if either parmsId or destination are null</exception>
/// <exception cref="ArgumentException">if parmsId is not valid for the encryption parameters</exception>
/// <exception cref="ArgumentException">if pool is uninitialized</exception>
public void EncryptZeroSymmetric(ParmsId parmsId, Ciphertext destination, MemoryPoolHandle pool = null)
{
if (null == parmsId)
{
throw new ArgumentNullException(nameof(parmsId));
}
if (null == destination)
{
throw new ArgumentNullException(nameof(destination));
}
IntPtr poolHandle = pool?.NativePtr ?? IntPtr.Zero;
NativeMethods.Encryptor_EncryptZeroSymmetric1(NativePtr, parmsId.Block, false, destination.NativePtr, poolHandle);
}
/// <summary>
/// Encrypts a plaintext with the secret key and stores the result in destination.
/// </summary>
/// <remarks>
/// The encryption parameters for the resulting ciphertext correspond to:
/// 1) in BFV, the highest (data) level in the modulus switching chain,
/// 2) in CKKS, the encryption parameters of the plaintext.
/// Dynamic memory allocations in the process are allocated from the memory
/// pool pointed to by the given MemoryPoolHandle.
/// </remarks>
/// <param name="plain">The plaintext to encrypt</param>
/// <param name="destination">The ciphertext to overwrite with the encrypted plaintext</param>
/// <param name="pool">The MemoryPoolHandle pointing to a valid memory pool</param>
/// <exception cref="ArgumentNullException">if either plain or destination are null</exception>
/// <exception cref="ArgumentException">if plain is not valid for the encryption parameters</exception>
/// <exception cref="ArgumentException">if plain is not in default NTT form</exception>
/// <exception cref="ArgumentException">if pool is uninitialized</exception>
public void EncryptSymmetric(Plaintext plain, Ciphertext destination, MemoryPoolHandle pool = null)
{
if (null == plain)
{
throw new ArgumentNullException(nameof(plain));
}
if (null == destination)
{
throw new ArgumentNullException(nameof(destination));
}
IntPtr poolHandle = pool?.NativePtr ?? IntPtr.Zero;
NativeMethods.Encryptor_EncryptSymmetric(NativePtr, plain.NativePtr, false, destination.NativePtr, poolHandle);
}
/// <summary>
/// Encrypts a zero plaintext with the secret key and returns the ciphertext
/// as a serializable object.
/// </summary>
/// <remarks>
/// <para>
/// Encrypts a zero plaintext with the secret key and returns the ciphertext
/// as a serializable object.
/// </para>
/// <para>
/// Half of the ciphertext data is pseudo-randomly generated from a seed to
/// reduce the object size. The resulting serializable object cannot be used
/// directly and is meant to be serialized for the size reduction to have an
/// impact.
/// </para>
/// <para>
/// The encryption parameters for the resulting ciphertext correspond to
/// the given ParmsId. Dynamic memory allocations in the process are allocated
/// from the memory pool pointed to by the given MemoryPoolHandle.
/// </para>
/// </remarks>
/// <param name="parmsId">The ParmsId for the resulting ciphertext</param>
/// <param name="pool">The MemoryPoolHandle pointing to a valid memory
/// pool</param>
/// <exception cref="ArgumentNullException">if parmsId is null</exception>
/// <exception cref="InvalidOperationException">if a secret key is not
/// set</exception>
/// <exception cref="ArgumentException">if parmsId is not valid for the
/// encryption parameters</exception>
/// <exception cref="ArgumentException">if pool is uninitialized</exception>
public Serializable <Ciphertext> EncryptZeroSymmetric(
ParmsId parmsId,
MemoryPoolHandle pool = null)
{
if (null == parmsId)
{
throw new ArgumentNullException(nameof(parmsId));
}
IntPtr poolHandle = pool?.NativePtr ?? IntPtr.Zero;
Ciphertext destination = new Ciphertext();
NativeMethods.Encryptor_EncryptZeroSymmetric1(
NativePtr, parmsId.Block, true, destination.NativePtr, poolHandle);
return(new Serializable <Ciphertext>(destination));
}
/// <summary>
/// Encrypts a plaintext with the secret key and returns the ciphertext as
/// a serializable object.
/// </summary>
/// <remarks>
/// <para>
/// Encrypts a plaintext with the secret key and returns the ciphertext as
/// a serializable object.
/// </para>
/// <para>
/// Half of the ciphertext data is pseudo-randomly generated from a seed to
/// reduce the object size. The resulting serializable object cannot be used
/// directly and is meant to be serialized for the size reduction to have an
/// impact.
/// </para>
/// <para>
/// The encryption parameters for the resulting ciphertext correspond to:
/// 1) in BFV, the highest (data) level in the modulus switching chain,
/// 2) in CKKS, the encryption parameters of the plaintext.
/// Dynamic memory allocations in the process are allocated from the memory
/// pool pointed to by the given MemoryPoolHandle.
/// </para>
/// </remarks>
/// <param name="plain">The plaintext to encrypt</param>
/// <param name="pool">The MemoryPoolHandle pointing to a valid memory pool</param>
/// <exception cref="ArgumentNullException">if plain is null</exception>
/// <exception cref="InvalidOperationException">if a secret key is not set</exception>
/// <exception cref="ArgumentException">if plain is not valid for the encryption
/// parameters</exception>
/// <exception cref="ArgumentException">if plain is not in default NTT
/// form</exception>
/// <exception cref="ArgumentException">if pool is uninitialized</exception>
public Serializable <Ciphertext> EncryptSymmetric(
Plaintext plain,
MemoryPoolHandle pool = null)
{
if (null == plain)
{
throw new ArgumentNullException(nameof(plain));
}
IntPtr poolHandle = pool?.NativePtr ?? IntPtr.Zero;
Ciphertext destination = new Ciphertext();
NativeMethods.Encryptor_EncryptSymmetric(
NativePtr, plain.NativePtr, true, destination.NativePtr, poolHandle);
return(new Serializable <Ciphertext>(destination));
}
