https://github.com/weidai11/cryptopp
xed25519.h
// xed25519.h - written and placed in public domain by Jeffrey Walton
// Crypto++ specific implementation wrapped around Andrew
// Moon's public domain curve25519-donna and ed25519-donna,
// http://github.com/floodyberry/curve25519-donna and
// http://github.com/floodyberry/ed25519-donna.
// Typically the key agreement classes encapsulate their data more
// than x25519 does below. They are a little more accessible
// due to crypto_box operations.
/// \file xed25519.h
/// \brief Classes for x25519 and ed25519 operations
/// \details This implementation integrates Andrew Moon's public domain code
/// for curve25519-donna and ed25519-donna.
/// \details Moving keys into and out of the library proceeds as follows.
/// If an Integer class is accepted or returned, then the data is in big
/// endian format. That is, the MSB is at byte position 0, and the LSB
/// is at byte position 31. The Integer will work as expected, just like
/// an int or a long.
/// \details If a byte array is accepted, then the byte array is in little
/// endian format. That is, the LSB is at byte position 0, and the MSB is
/// at byte position 31. This follows the implementation where byte 0 is
/// clamed with 248. That is my_arr[0] &= 248 to mask the lower 3 bits.
/// \details PKCS8 and X509 keys encoded using ASN.1 follow little endian
/// arrays. The format is specified in <A HREF=
/// "http:///tools.ietf.org/html/draft-ietf-curdle-pkix">draft-ietf-curdle-pkix</A>.
/// \details If you have a little endian array and you want to wrap it in
/// an Integer using big endian then you can perform the following:
/// <pre>Integer x(my_arr, SECRET_KEYLENGTH, UNSIGNED, LITTLE_ENDIAN_ORDER);</pre>
/// \sa Andrew Moon's x22519 GitHub <A
/// HREF="http://github.com/floodyberry/curve25519-donna">curve25519-donna</A>,
/// ed22519 GitHub <A
/// HREF="http://github.com/floodyberry/ed25519-donna">ed25519-donna</A>, and
/// <A HREF="http:///tools.ietf.org/html/draft-ietf-curdle-pkix">draft-ietf-curdle-pkix</A>
/// \since Crypto++ 8.0
#ifndef CRYPTOPP_XED25519_H
#define CRYPTOPP_XED25519_H
#include "cryptlib.h"
#include "pubkey.h"
#include "oids.h"
NAMESPACE_BEGIN(CryptoPP)
class Integer;
struct ed25519Signer;
struct ed25519Verifier;
// ******************** x25519 Agreement ************************* //
/// \brief x25519 with key validation
/// \since Crypto++ 8.0
class x25519 : public SimpleKeyAgreementDomain, public CryptoParameters, public PKCS8PrivateKey
{
public:
/// \brief Size of the private key
/// \details SECRET_KEYLENGTH is the size of the private key, in bytes.
CRYPTOPP_CONSTANT(SECRET_KEYLENGTH = 32);
/// \brief Size of the public key
/// \details PUBLIC_KEYLENGTH is the size of the public key, in bytes.
CRYPTOPP_CONSTANT(PUBLIC_KEYLENGTH = 32);
/// \brief Size of the shared key
/// \details SHARED_KEYLENGTH is the size of the shared key, in bytes.
CRYPTOPP_CONSTANT(SHARED_KEYLENGTH = 32);
virtual ~x25519() {}
/// \brief Create a x25519 object
/// \details This constructor creates an empty x25519 object. It is
/// intended for use in loading existing parameters, like CryptoBox
/// parameters. If you are performing key agreement you should use a
/// constructor that generates random parameters on construction.
x25519() {}
/// \brief Create a x25519 object
/// \param y public key
/// \param x private key
/// \details This constructor creates a x25519 object using existing parameters.
/// \note The public key is not validated.
x25519(const byte y[PUBLIC_KEYLENGTH], const byte x[SECRET_KEYLENGTH]);
/// \brief Create a x25519 object
/// \param x private key
/// \details This constructor creates a x25519 object using existing parameters.
/// The public key is calculated from the private key.
x25519(const byte x[SECRET_KEYLENGTH]);
/// \brief Create a x25519 object
/// \param y public key
/// \param x private key
/// \details This constructor creates a x25519 object using existing parameters.
/// \note The public key is not validated.
x25519(const Integer &y, const Integer &x);
/// \brief Create a x25519 object
/// \param x private key
/// \details This constructor creates a x25519 object using existing parameters.
/// The public key is calculated from the private key.
x25519(const Integer &x);
/// \brief Create a x25519 object
/// \param rng RandomNumberGenerator derived class
/// \details This constructor creates a new x25519 using the random number generator.
x25519(RandomNumberGenerator &rng);
/// \brief Create a x25519 object
/// \param params public and private key
/// \details This constructor creates a x25519 object using existing parameters.
/// The <tt>params</tt> can be created with <tt>Save</tt>.
/// \note The public key is not validated.
x25519(BufferedTransformation ¶ms);
/// \brief Create a x25519 object
/// \param oid an object identifier
/// \details This constructor creates a new x25519 using the specified OID. The public
/// and private points are uninitialized.
x25519(const OID &oid);
/// \brief Clamp a private key
/// \param x private key
/// \details ClampKeys() clamps a private key and then regenerates the
/// public key from the private key.
void ClampKey(byte x[SECRET_KEYLENGTH]) const;
/// \brief Determine if private key is clamped
/// \param x private key
bool IsClamped(const byte x[SECRET_KEYLENGTH]) const;
/// \brief Test if a key has small order
/// \param y public key
bool IsSmallOrder(const byte y[PUBLIC_KEYLENGTH]) const;
/// \brief Get the Object Identifier
/// \return the Object Identifier
/// \details The default OID is from RFC 8410 using <tt>id-X25519</tt>.
/// The default private key format is RFC 5208.
OID GetAlgorithmID() const {
return m_oid.Empty() ? ASN1::X25519() : m_oid;
}
/// \brief Set the Object Identifier
/// \param oid the new Object Identifier
void SetAlgorithmID(const OID& oid) {
m_oid = oid;
}
// CryptoParameters
bool Validate(RandomNumberGenerator &rng, unsigned int level) const;
bool GetVoidValue(const char *name, const std::type_info &valueType, void *pValue) const;
void AssignFrom(const NameValuePairs &source);
// CryptoParameters
CryptoParameters & AccessCryptoParameters() {return *this;}
/// \brief DER encode ASN.1 object
/// \param bt BufferedTransformation object
/// \details Save() will write the OID associated with algorithm or scheme.
/// In the case of public and private keys, this function writes the
/// subjectPublicKeyInfo parts.
/// \details The default OID is from RFC 8410 using <tt>id-X25519</tt>.
/// The default private key format is RFC 5208, which is the old format.
/// The old format provides the best interop, and keys will work
/// with OpenSSL.
/// \sa <A HREF="http://tools.ietf.org/rfc/rfc5958.txt">RFC 5958, Asymmetric
/// Key Packages</A>
void Save(BufferedTransformation &bt) const {
DEREncode(bt, 0);
}
/// \brief DER encode ASN.1 object
/// \param bt BufferedTransformation object
/// \param v1 flag indicating v1
/// \details Save() will write the OID associated with algorithm or scheme.
/// In the case of public and private keys, this function writes the
/// subjectPublicKeyInfo parts.
/// \details The default OID is from RFC 8410 using <tt>id-X25519</tt>.
/// The default private key format is RFC 5208.
/// \details v1 means INTEGER 0 is written. INTEGER 0 means
/// RFC 5208 format, which is the old format. The old format provides
/// the best interop, and keys will work with OpenSSL. The other
/// option uses INTEGER 1. INTEGER 1 means RFC 5958 format,
/// which is the new format.
/// \sa <A HREF="http://tools.ietf.org/rfc/rfc5958.txt">RFC 5958, Asymmetric
/// Key Packages</A>
void Save(BufferedTransformation &bt, bool v1) const {
DEREncode(bt, v1 ? 0 : 1);
}
/// \brief BER decode ASN.1 object
/// \param bt BufferedTransformation object
/// \sa <A HREF="http://tools.ietf.org/rfc/rfc5958.txt">RFC 5958, Asymmetric
/// Key Packages</A>
void Load(BufferedTransformation &bt) {
BERDecode(bt);
}
// PKCS8PrivateKey
void BERDecode(BufferedTransformation &bt);
void DEREncode(BufferedTransformation &bt) const { DEREncode(bt, 0); }
void BERDecodePrivateKey(BufferedTransformation &bt, bool parametersPresent, size_t size);
void DEREncodePrivateKey(BufferedTransformation &bt) const;
/// \brief DER encode ASN.1 object
/// \param bt BufferedTransformation object
/// \param version indicates version
/// \details DEREncode() will write the OID associated with algorithm or
/// scheme. In the case of public and private keys, this function writes
/// the subjectPublicKeyInfo parts.
/// \details The default OID is from RFC 8410 using <tt>id-X25519</tt>.
/// The default private key format is RFC 5208.
/// \details The value of version is written as the INTEGER. INTEGER 0 means
/// RFC 5208 format, which is the old format. The old format provides
/// the best interop, and keys will work with OpenSSL. The INTEGER 1
/// means RFC 5958 format, which is the new format.
void DEREncode(BufferedTransformation &bt, int version) const;
/// \brief Determine if OID is valid for this object
/// \details BERDecodeAndCheckAlgorithmID() parses the OID from
/// <tt>bt</tt> and determines if it valid for this object. The
/// problem in practice is there are multiple OIDs available to
/// denote curve25519 operations. The OIDs include an old GNU
/// OID used by SSH, OIDs specified in draft-josefsson-pkix-newcurves,
/// and OIDs specified in draft-ietf-curdle-pkix.
/// \details By default BERDecodeAndCheckAlgorithmID() accepts an
/// OID set by the user, <tt>ASN1::curve25519()</tt> and <tt>ASN1::X25519()</tt>.
/// <tt>ASN1::curve25519()</tt> is generic and says "this key is valid for
/// curve25519 operations". <tt>ASN1::X25519()</tt> is specific and says
/// "this key is valid for x25519 key exchange."
void BERDecodeAndCheckAlgorithmID(BufferedTransformation& bt);
// DL_PrivateKey
void GenerateRandom(RandomNumberGenerator &rng, const NameValuePairs ¶ms);
// SimpleKeyAgreementDomain
unsigned int AgreedValueLength() const {return SHARED_KEYLENGTH;}
unsigned int PrivateKeyLength() const {return SECRET_KEYLENGTH;}
unsigned int PublicKeyLength() const {return PUBLIC_KEYLENGTH;}
// SimpleKeyAgreementDomain
void GeneratePrivateKey(RandomNumberGenerator &rng, byte *privateKey) const;
void GeneratePublicKey(RandomNumberGenerator &rng, const byte *privateKey, byte *publicKey) const;
bool Agree(byte *agreedValue, const byte *privateKey, const byte *otherPublicKey, bool validateOtherPublicKey=true) const;
protected:
// Create a public key from a private key
void SecretToPublicKey(byte y[PUBLIC_KEYLENGTH], const byte x[SECRET_KEYLENGTH]) const;
protected:
FixedSizeSecBlock<byte, SECRET_KEYLENGTH> m_sk;
FixedSizeSecBlock<byte, PUBLIC_KEYLENGTH> m_pk;
OID m_oid; // preferred OID
};
// ****************** ed25519 Signer *********************** //
/// \brief ed25519 message accumulator
/// \details ed25519 buffers the entire message, and does not
/// digest the message incrementally. You should be careful with
/// large messages like files on-disk. The behavior is by design
/// because Bernstein feels small messages should be authenticated;
/// and larger messages will be digested by the application.
/// \details The accumulator is used for signing and verification.
/// The first 64-bytes of storage is reserved for the signature.
/// During signing the signature storage is unused. During
/// verification the first 64 bytes holds the signature. The
/// signature is provided by the PK_Verifier framework and the
/// call to PK_Signer::InputSignature. Member functions data()
/// and size() refer to the accumulated message. Member function
/// signature() refers to the signature with an implicit size of
/// SIGNATURE_LENGTH bytes.
/// \details Applications which digest large messages, like an ISO
/// disk file, should take care because the design effectively
/// disgorges the format operation from the signing operation.
/// Put another way, be careful to ensure what you are signing is
/// is in fact a digest of the intended message, and not a different
/// message digest supplied by an attacker.
struct ed25519_MessageAccumulator : public PK_MessageAccumulator
{
CRYPTOPP_CONSTANT(RESERVE_SIZE=2048+64);
CRYPTOPP_CONSTANT(SIGNATURE_LENGTH=64);
/// \brief Create a message accumulator
ed25519_MessageAccumulator() {
Restart();
}
/// \brief Create a message accumulator
/// \details ed25519 does not use a RNG. You can safely use
/// NullRNG() because IsProbablistic returns false.
ed25519_MessageAccumulator(RandomNumberGenerator &rng) {
CRYPTOPP_UNUSED(rng); Restart();
}
/// \brief Add data to the accumulator
/// \param msg pointer to the data to accumulate
/// \param len the size of the data, in bytes
void Update(const byte* msg, size_t len) {
if (msg && len)
m_msg.insert(m_msg.end(), msg, msg+len);
}
/// \brief Reset the accumulator
void Restart() {
m_msg.reserve(RESERVE_SIZE);
m_msg.resize(SIGNATURE_LENGTH);
}
/// \brief Retrieve pointer to signature buffer
/// \return pointer to signature buffer
byte* signature() {
return &m_msg[0];
}
/// \brief Retrieve pointer to signature buffer
/// \return pointer to signature buffer
const byte* signature() const {
return &m_msg[0];
}
/// \brief Retrieve pointer to data buffer
/// \return pointer to data buffer
const byte* data() const {
return &m_msg[0]+SIGNATURE_LENGTH;
}
/// \brief Retrieve size of data buffer
/// \return size of the data buffer, in bytes
size_t size() const {
return m_msg.size()-SIGNATURE_LENGTH;
}
protected:
// TODO: Find an equivalent Crypto++ structure.
std::vector<byte, AllocatorWithCleanup<byte> > m_msg;
};
/// \brief Ed25519 private key
/// \details ed25519PrivateKey is somewhat of a hack. It needed to
/// provide DL_PrivateKey interface to fit into the existing
/// framework, but it lacks a lot of the internals of a true
/// DL_PrivateKey. The missing pieces include GroupParameters
/// and Point, which provide the low level field operations
/// found in traditional implementations like NIST curves over
/// prime and binary fields.
/// \details ed25519PrivateKey is also unusual because the
/// class members of interest are byte arrays and not Integers.
/// In addition, the byte arrays are little-endian meaning
/// LSB is at element 0 and the MSB is at element 31.
/// If you call GetPrivateExponent() then the little-endian byte
/// array is converted to a big-endian Integer() so it can be
/// returned the way a caller expects. And calling
/// SetPrivateExponent performs a similar internal conversion.
/// \since Crypto++ 8.0
struct ed25519PrivateKey : public PKCS8PrivateKey
{
/// \brief Size of the private key
/// \details SECRET_KEYLENGTH is the size of the private key, in bytes.
CRYPTOPP_CONSTANT(SECRET_KEYLENGTH = 32);
/// \brief Size of the public key
/// \details PUBLIC_KEYLENGTH is the size of the public key, in bytes.
CRYPTOPP_CONSTANT(PUBLIC_KEYLENGTH = 32);
/// \brief Size of the signature
/// \details SIGNATURE_LENGTH is the size of the signature, in bytes.
/// ed25519 is a DL-based signature scheme. The signature is the
/// concatenation of <tt>r || s</tt>.
CRYPTOPP_CONSTANT(SIGNATURE_LENGTH = 64);
virtual ~ed25519PrivateKey() {}
// CryptoMaterial
bool Validate(RandomNumberGenerator &rng, unsigned int level) const;
bool GetVoidValue(const char *name, const std::type_info &valueType, void *pValue) const;
void AssignFrom(const NameValuePairs &source);
// GroupParameters
OID GetAlgorithmID() const {
return m_oid.Empty() ? ASN1::Ed25519() : m_oid;
}
/// \brief DER encode ASN.1 object
/// \param bt BufferedTransformation object
/// \details Save() will write the OID associated with algorithm or scheme.
/// In the case of public and private keys, this function writes the
/// subjectPublicKeyInfo parts.
/// \details The default OID is from RFC 8410 using <tt>id-Ed25519</tt>.
/// The default private key format is RFC 5208, which is the old format.
/// The old format provides the best interop, and keys will work
/// with OpenSSL.
/// \sa <A HREF="http://tools.ietf.org/rfc/rfc5958.txt">RFC 5958, Asymmetric
/// Key Packages</A>
void Save(BufferedTransformation &bt) const {
DEREncode(bt, 0);
}
/// \brief DER encode ASN.1 object
/// \param bt BufferedTransformation object
/// \param v1 flag indicating v1
/// \details Save() will write the OID associated with algorithm or scheme.
/// In the case of public and private keys, this function writes the
/// subjectPublicKeyInfo parts.
/// \details The default OID is from RFC 8410 using <tt>id-Ed25519</tt>.
/// The default private key format is RFC 5208.
/// \details v1 means INTEGER 0 is written. INTEGER 0 means
/// RFC 5208 format, which is the old format. The old format provides
/// the best interop, and keys will work with OpenSSL. The other
/// option uses INTEGER 1. INTEGER 1 means RFC 5958 format,
/// which is the new format.
/// \sa <A HREF="http://tools.ietf.org/rfc/rfc5958.txt">RFC 5958, Asymmetric
/// Key Packages</A>
void Save(BufferedTransformation &bt, bool v1) const {
DEREncode(bt, v1 ? 0 : 1);
}
/// \brief BER decode ASN.1 object
/// \param bt BufferedTransformation object
/// \sa <A HREF="http://tools.ietf.org/rfc/rfc5958.txt">RFC 5958, Asymmetric
/// Key Packages</A>
void Load(BufferedTransformation &bt) {
BERDecode(bt);
}
/// \brief Initializes a public key from this key
/// \param pub reference to a public key
void MakePublicKey(PublicKey &pub) const;
// PKCS8PrivateKey
void BERDecode(BufferedTransformation &bt);
void DEREncode(BufferedTransformation &bt) const { DEREncode(bt, 0); }
void BERDecodePrivateKey(BufferedTransformation &bt, bool parametersPresent, size_t size);
void DEREncodePrivateKey(BufferedTransformation &bt) const;
/// \brief DER encode ASN.1 object
/// \param bt BufferedTransformation object
/// \param version indicates version
/// \details DEREncode() will write the OID associated with algorithm or
/// scheme. In the case of public and private keys, this function writes
/// the subjectPublicKeyInfo parts.
/// \details The default OID is from RFC 8410 using <tt>id-X25519</tt>.
/// The default private key format is RFC 5208.
/// \details The value of version is written as the INTEGER. INTEGER 0 means
/// RFC 5208 format, which is the old format. The old format provides
/// the best interop, and keys will work with OpenSSL. The INTEGER 1
/// means RFC 5958 format, which is the new format.
void DEREncode(BufferedTransformation &bt, int version) const;
/// \brief Determine if OID is valid for this object
/// \details BERDecodeAndCheckAlgorithmID() parses the OID from
/// <tt>bt</tt> and determines if it valid for this object. The
/// problem in practice is there are multiple OIDs available to
/// denote curve25519 operations. The OIDs include an old GNU
/// OID used by SSH, OIDs specified in draft-josefsson-pkix-newcurves,
/// and OIDs specified in draft-ietf-curdle-pkix.
/// \details By default BERDecodeAndCheckAlgorithmID() accepts an
/// OID set by the user, <tt>ASN1::curve25519()</tt> and <tt>ASN1::Ed25519()</tt>.
/// <tt>ASN1::curve25519()</tt> is generic and says "this key is valid for
/// curve25519 operations". <tt>ASN1::Ed25519()</tt> is specific and says
/// "this key is valid for ed25519 signing."
void BERDecodeAndCheckAlgorithmID(BufferedTransformation& bt);
// PKCS8PrivateKey
void GenerateRandom(RandomNumberGenerator &rng, const NameValuePairs ¶ms);
void SetPrivateExponent(const byte x[SECRET_KEYLENGTH]);
void SetPrivateExponent(const Integer &x);
const Integer& GetPrivateExponent() const;
/// \brief Test if a key has small order
/// \param y public key
bool IsSmallOrder(const byte y[PUBLIC_KEYLENGTH]) const;
/// \brief Retrieve private key byte array
/// \return the private key byte array
/// \details GetPrivateKeyBytePtr() is used by signing code to call ed25519_sign.
const byte* GetPrivateKeyBytePtr() const {
return m_sk.begin();
}
/// \brief Retrieve public key byte array
/// \return the public key byte array
/// \details GetPublicKeyBytePtr() is used by signing code to call ed25519_sign.
const byte* GetPublicKeyBytePtr() const {
return m_pk.begin();
}
protected:
// Create a public key from a private key
void SecretToPublicKey(byte y[PUBLIC_KEYLENGTH], const byte x[SECRET_KEYLENGTH]) const;
protected:
FixedSizeSecBlock<byte, SECRET_KEYLENGTH> m_sk;
FixedSizeSecBlock<byte, PUBLIC_KEYLENGTH> m_pk;
OID m_oid; // preferred OID
mutable Integer m_x; // for DL_PrivateKey
};
/// \brief Ed25519 signature algorithm
/// \since Crypto++ 8.0
struct ed25519Signer : public PK_Signer
{
/// \brief Size of the private key
/// \details SECRET_KEYLENGTH is the size of the private key, in bytes.
CRYPTOPP_CONSTANT(SECRET_KEYLENGTH = 32);
/// \brief Size of the public key
/// \details PUBLIC_KEYLENGTH is the size of the public key, in bytes.
CRYPTOPP_CONSTANT(PUBLIC_KEYLENGTH = 32);
/// \brief Size of the signature
/// \details SIGNATURE_LENGTH is the size of the signature, in bytes.
/// ed25519 is a DL-based signature scheme. The signature is the
/// concatenation of <tt>r || s</tt>.
CRYPTOPP_CONSTANT(SIGNATURE_LENGTH = 64);
typedef Integer Element;
virtual ~ed25519Signer() {}
/// \brief Create an ed25519Signer object
ed25519Signer() {}
/// \brief Create an ed25519Signer object
/// \param y public key
/// \param x private key
/// \details This constructor creates an ed25519Signer object using existing parameters.
/// \note The public key is not validated.
ed25519Signer(const byte y[PUBLIC_KEYLENGTH], const byte x[SECRET_KEYLENGTH]);
/// \brief Create an ed25519Signer object
/// \param x private key
/// \details This constructor creates an ed25519Signer object using existing parameters.
/// The public key is calculated from the private key.
ed25519Signer(const byte x[SECRET_KEYLENGTH]);
/// \brief Create an ed25519Signer object
/// \param y public key
/// \param x private key
/// \details This constructor creates an ed25519Signer object using existing parameters.
/// \note The public key is not validated.
ed25519Signer(const Integer &y, const Integer &x);
/// \brief Create an ed25519Signer object
/// \param x private key
/// \details This constructor creates an ed25519Signer object using existing parameters.
/// The public key is calculated from the private key.
ed25519Signer(const Integer &x);
/// \brief Create an ed25519Signer object
/// \param key PKCS8 private key
/// \details This constructor creates an ed25519Signer object using existing private key.
/// \note The keys are not validated.
/// \since Crypto++ 8.6
ed25519Signer(const PKCS8PrivateKey &key);
/// \brief Create an ed25519Signer object
/// \param rng RandomNumberGenerator derived class
/// \details This constructor creates a new ed25519Signer using the random number generator.
ed25519Signer(RandomNumberGenerator &rng);
/// \brief Create an ed25519Signer object
/// \param params public and private key
/// \details This constructor creates an ed25519Signer object using existing parameters.
/// The <tt>params</tt> can be created with <tt>Save</tt>.
/// \note The public key is not validated.
ed25519Signer(BufferedTransformation ¶ms);
// DL_ObjectImplBase
/// \brief Retrieves a reference to a Private Key
/// \details AccessKey() retrieves a non-const reference to a private key.
PrivateKey& AccessKey() { return m_key; }
PrivateKey& AccessPrivateKey() { return m_key; }
/// \brief Retrieves a reference to a Private Key
/// \details AccessKey() retrieves a const reference to a private key.
const PrivateKey& GetKey() const { return m_key; }
const PrivateKey& GetPrivateKey() const { return m_key; }
// DL_SignatureSchemeBase
size_t SignatureLength() const { return SIGNATURE_LENGTH; }
size_t MaxRecoverableLength() const { return 0; }
size_t MaxRecoverableLengthFromSignatureLength(size_t signatureLength) const {
CRYPTOPP_UNUSED(signatureLength); return 0;
}
bool IsProbabilistic() const { return false; }
bool AllowNonrecoverablePart() const { return false; }
bool RecoverablePartFirst() const { return false; }
PK_MessageAccumulator* NewSignatureAccumulator(RandomNumberGenerator &rng) const {
return new ed25519_MessageAccumulator(rng);
}
void InputRecoverableMessage(PK_MessageAccumulator &messageAccumulator, const byte *recoverableMessage, size_t recoverableMessageLength) const {
CRYPTOPP_UNUSED(messageAccumulator); CRYPTOPP_UNUSED(recoverableMessage);
CRYPTOPP_UNUSED(recoverableMessageLength);
throw NotImplemented("ed25519Signer: this object does not support recoverable messages");
}
size_t SignAndRestart(RandomNumberGenerator &rng, PK_MessageAccumulator &messageAccumulator, byte *signature, bool restart) const;
/// \brief Sign a stream
/// \param rng a RandomNumberGenerator derived class
/// \param stream an std::istream derived class
/// \param signature a block of bytes for the signature
/// \return actual signature length
/// \details SignStream() handles large streams. The Stream functions were added to
/// ed25519 for signing and verifying files that are too large for a memory allocation.
/// The functions are not present in other library signers and verifiers.
/// \details ed25519 is a deterministic signature scheme. <tt>IsProbabilistic()</tt>
/// returns false and the random number generator can be <tt>NullRNG()</tt>.
/// \pre <tt>COUNTOF(signature) == MaxSignatureLength()</tt>
/// \since Crypto++ 8.1
size_t SignStream (RandomNumberGenerator &rng, std::istream& stream, byte *signature) const;
protected:
ed25519PrivateKey m_key;
};
// ****************** ed25519 Verifier *********************** //
/// \brief Ed25519 public key
/// \details ed25519PublicKey is somewhat of a hack. It needed to
/// provide DL_PublicKey interface to fit into the existing
/// framework, but it lacks a lot of the internals of a true
/// DL_PublicKey. The missing pieces include GroupParameters
/// and Point, which provide the low level field operations
/// found in traditional implementations like NIST curves over
/// prime and binary fields.
/// \details ed25519PublicKey is also unusual because the
/// class members of interest are byte arrays and not Integers.
/// In addition, the byte arrays are little-endian meaning
/// LSB is at element 0 and the MSB is at element 31.
/// If you call GetPublicElement() then the little-endian byte
/// array is converted to a big-endian Integer() so it can be
/// returned the way a caller expects. And calling
/// SetPublicElement() performs a similar internal conversion.
/// \since Crypto++ 8.0
struct ed25519PublicKey : public X509PublicKey
{
/// \brief Size of the public key
/// \details PUBLIC_KEYLENGTH is the size of the public key, in bytes.
CRYPTOPP_CONSTANT(PUBLIC_KEYLENGTH = 32);
typedef Integer Element;
virtual ~ed25519PublicKey() {}
OID GetAlgorithmID() const {
return m_oid.Empty() ? ASN1::Ed25519() : m_oid;
}
/// \brief DER encode ASN.1 object
/// \param bt BufferedTransformation object
/// \details Save() will write the OID associated with algorithm or scheme.
/// In the case of public and private keys, this function writes the
/// subjectPublicKeyInfo parts.
/// \details The default OID is from RFC 8410 using <tt>id-X25519</tt>.
/// The default private key format is RFC 5208, which is the old format.
/// The old format provides the best interop, and keys will work
/// with OpenSSL.
void Save(BufferedTransformation &bt) const {
DEREncode(bt);
}
/// \brief BER decode ASN.1 object
/// \param bt BufferedTransformation object
/// \sa <A HREF="http://tools.ietf.org/rfc/rfc5958.txt">RFC 5958, Asymmetric
/// Key Packages</A>
void Load(BufferedTransformation &bt) {
BERDecode(bt);
}
// X509PublicKey
void BERDecode(BufferedTransformation &bt);
void DEREncode(BufferedTransformation &bt) const;
void BERDecodePublicKey(BufferedTransformation &bt, bool parametersPresent, size_t size);
void DEREncodePublicKey(BufferedTransformation &bt) const;
/// \brief Determine if OID is valid for this object
/// \details BERDecodeAndCheckAlgorithmID() parses the OID from
/// <tt>bt</tt> and determines if it valid for this object. The
/// problem in practice is there are multiple OIDs available to
/// denote curve25519 operations. The OIDs include an old GNU
/// OID used by SSH, OIDs specified in draft-josefsson-pkix-newcurves,
/// and OIDs specified in draft-ietf-curdle-pkix.
/// \details By default BERDecodeAndCheckAlgorithmID() accepts an
/// OID set by the user, <tt>ASN1::curve25519()</tt> and <tt>ASN1::Ed25519()</tt>.
/// <tt>ASN1::curve25519()</tt> is generic and says "this key is valid for
/// curve25519 operations". <tt>ASN1::Ed25519()</tt> is specific and says
/// "this key is valid for ed25519 signing."
void BERDecodeAndCheckAlgorithmID(BufferedTransformation& bt);
bool Validate(RandomNumberGenerator &rng, unsigned int level) const;
bool GetVoidValue(const char *name, const std::type_info &valueType, void *pValue) const;
void AssignFrom(const NameValuePairs &source);
// DL_PublicKey
void SetPublicElement(const byte y[PUBLIC_KEYLENGTH]);
void SetPublicElement(const Element &y);
const Element& GetPublicElement() const;
/// \brief Retrieve public key byte array
/// \return the public key byte array
/// \details GetPublicKeyBytePtr() is used by signing code to call ed25519_sign.
const byte* GetPublicKeyBytePtr() const {
return m_pk.begin();
}
protected:
FixedSizeSecBlock<byte, PUBLIC_KEYLENGTH> m_pk;
OID m_oid; // preferred OID
mutable Integer m_y; // for DL_PublicKey
};
/// \brief Ed25519 signature verification algorithm
/// \since Crypto++ 8.0
struct ed25519Verifier : public PK_Verifier
{
CRYPTOPP_CONSTANT(PUBLIC_KEYLENGTH = 32);
CRYPTOPP_CONSTANT(SIGNATURE_LENGTH = 64);
typedef Integer Element;
virtual ~ed25519Verifier() {}
/// \brief Create an ed25519Verifier object
ed25519Verifier() {}
/// \brief Create an ed25519Verifier object
/// \param y public key
/// \details This constructor creates an ed25519Verifier object using existing parameters.
/// \note The public key is not validated.
ed25519Verifier(const byte y[PUBLIC_KEYLENGTH]);
/// \brief Create an ed25519Verifier object
/// \param y public key
/// \details This constructor creates an ed25519Verifier object using existing parameters.
/// \note The public key is not validated.
ed25519Verifier(const Integer &y);
/// \brief Create an ed25519Verifier object
/// \param key X509 public key
/// \details This constructor creates an ed25519Verifier object using an existing public key.
/// \note The public key is not validated.
/// \since Crypto++ 8.6
ed25519Verifier(const X509PublicKey &key);
/// \brief Create an ed25519Verifier object
/// \param params public and private key
/// \details This constructor creates an ed25519Verifier object using existing parameters.
/// The <tt>params</tt> can be created with <tt>Save</tt>.
/// \note The public key is not validated.
ed25519Verifier(BufferedTransformation ¶ms);
/// \brief Create an ed25519Verifier object
/// \param signer ed25519 signer object
/// \details This constructor creates an ed25519Verifier object using existing parameters.
/// The <tt>params</tt> can be created with <tt>Save</tt>.
/// \note The public key is not validated.
ed25519Verifier(const ed25519Signer& signer);
// DL_ObjectImplBase
/// \brief Retrieves a reference to a Public Key
/// \details AccessKey() retrieves a non-const reference to a public key.
PublicKey& AccessKey() { return m_key; }
PublicKey& AccessPublicKey() { return m_key; }
/// \brief Retrieves a reference to a Public Key
/// \details GetKey() retrieves a const reference to a public key.
const PublicKey& GetKey() const { return m_key; }
const PublicKey& GetPublicKey() const { return m_key; }
// DL_SignatureSchemeBase
size_t SignatureLength() const { return SIGNATURE_LENGTH; }
size_t MaxRecoverableLength() const { return 0; }
size_t MaxRecoverableLengthFromSignatureLength(size_t signatureLength) const {
CRYPTOPP_UNUSED(signatureLength); return 0;
}
bool IsProbabilistic() const { return false; }
bool AllowNonrecoverablePart() const { return false; }
bool RecoverablePartFirst() const { return false; }
ed25519_MessageAccumulator* NewVerificationAccumulator() const {
return new ed25519_MessageAccumulator;
}
void InputSignature(PK_MessageAccumulator &messageAccumulator, const byte *signature, size_t signatureLength) const {
CRYPTOPP_ASSERT(signature != NULLPTR);
CRYPTOPP_ASSERT(signatureLength == SIGNATURE_LENGTH);
ed25519_MessageAccumulator& accum = static_cast<ed25519_MessageAccumulator&>(messageAccumulator);
if (signature && signatureLength)
std::memcpy(accum.signature(), signature, STDMIN((size_t)SIGNATURE_LENGTH, signatureLength));
}
bool VerifyAndRestart(PK_MessageAccumulator &messageAccumulator) const;
/// \brief Check whether input signature is a valid signature for input message
/// \param stream an std::istream derived class
/// \param signature a pointer to the signature over the message
/// \param signatureLen the size of the signature
/// \return true if the signature is valid, false otherwise
/// \details VerifyStream() handles large streams. The Stream functions were added to
/// ed25519 for signing and verifying files that are too large for a memory allocation.
/// The functions are not present in other library signers and verifiers.
/// \since Crypto++ 8.1
bool VerifyStream(std::istream& stream, const byte *signature, size_t signatureLen) const;
DecodingResult RecoverAndRestart(byte *recoveredMessage, PK_MessageAccumulator &messageAccumulator) const {
CRYPTOPP_UNUSED(recoveredMessage); CRYPTOPP_UNUSED(messageAccumulator);
throw NotImplemented("ed25519Verifier: this object does not support recoverable messages");
}
protected:
ed25519PublicKey m_key;
};
/// \brief Ed25519 signature scheme
/// \sa <A HREF="http://cryptopp.com/wiki/Ed25519">Ed25519</A> on the Crypto++ wiki.
/// \since Crypto++ 8.0
struct ed25519
{
/// \brief ed25519 Signer
typedef ed25519Signer Signer;
/// \brief ed25519 Verifier
typedef ed25519Verifier Verifier;
};
NAMESPACE_END // CryptoPP
#endif // CRYPTOPP_XED25519_H
