Class: Secp256k1::Signature

Inherits:
Object
  • Object
show all
Defined in:
ext/rbsecp256k1/rbsecp256k1.c

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.from_compact(in_compact_signature) ⇒ Secp256k1::Signature

Deserializes a Signature from 64-byte compact signature data.

Parameters:

  • in_compact_signature (String) —

    compact signature as 64-byte binary string.

Returns:

Raises:



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# File 'ext/rbsecp256k1/rbsecp256k1.c', line 949

static VALUE
Signature_from_compact(VALUE klass, VALUE in_compact_signature)
{
  Signature *signature;
  VALUE signature_result;
  unsigned char *signature_data;

  Check_Type(in_compact_signature, T_STRING);

  if (RSTRING_LEN(in_compact_signature) != 64)
  {
    rb_raise(Secp256k1_Error_class, "compact signature must be 64 bytes");
  }

  signature_data = (unsigned char*)StringValuePtr(in_compact_signature);

  signature_result = Signature_alloc(Secp256k1_Signature_class);
  TypedData_Get_Struct(signature_result, Signature, &Signature_DataType, signature);

  if (secp256k1_ecdsa_signature_parse_compact(secp256k1_context_static,
                                              &(signature->sig),
                                              signature_data) != 1)
  {
    rb_raise(Secp256k1_DeserializationError_class, "invalid compact signature");
    return Qnil;
  }

  return signature_result;
}

.from_der_encoded(in_der_encoded_signature) ⇒ Secp256k1::Signature

Converts a DER encoded binary signature into a signature object.

Parameters:

  • in_der_encoded_signature (String) —

    DER encoded signature as binary string.

Returns:

Raises:



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# File 'ext/rbsecp256k1/rbsecp256k1.c', line 988

static VALUE
Signature_from_der_encoded(VALUE klass, VALUE in_der_encoded_signature)
{
  Signature *signature;
  VALUE signature_result;
  unsigned char *signature_data;

  Check_Type(in_der_encoded_signature, T_STRING);

  signature_data = (unsigned char*)StringValuePtr(in_der_encoded_signature);

  signature_result = Signature_alloc(Secp256k1_Signature_class);
  TypedData_Get_Struct(signature_result, Signature, &Signature_DataType, signature);

  if (secp256k1_ecdsa_signature_parse_der(secp256k1_context_static,
                                          &(signature->sig),
                                          signature_data,
                                          RSTRING_LEN(in_der_encoded_signature)) != 1)
  {
    rb_raise(Secp256k1_DeserializationError_class, "invalid DER encoded signature");
    return Qnil;
  }

  return signature_result;
}

Instance Method Details

#==(other) ⇒ Boolean

Compares two signatures.

Two signatures are equal if their compact encodings are identical.

Parameters:

Returns:

  • (Boolean) —

    true if signatures match, false otherwise.



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# File 'ext/rbsecp256k1/rbsecp256k1.c', line 1123

static VALUE
Signature_equals(VALUE self, VALUE other)
{
  Signature *lhs;
  Signature *rhs;
  unsigned char lhs_compact[64];
  unsigned char rhs_compact[64];

  TypedData_Get_Struct(self, Signature, &Signature_DataType, lhs);
  TypedData_Get_Struct(other, Signature, &Signature_DataType, rhs);

  secp256k1_ecdsa_signature_serialize_compact(
    secp256k1_context_static, lhs_compact, &(lhs->sig)
  );
  secp256k1_ecdsa_signature_serialize_compact(
    secp256k1_context_static, rhs_compact, &(rhs->sig)
  );

  if (memcmp(lhs_compact, rhs_compact, 64) == 0)
  {
    return Qtrue;
  }

  return Qfalse;
}

#compact ⇒ String

Returns the 64 byte compact representation of this signature.

Returns:

  • (String) —

    64 byte binary string containing signature data.



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# File 'ext/rbsecp256k1/rbsecp256k1.c', line 1050

static VALUE
Signature_compact(VALUE self)
{
  // TODO: Cache value after first computation
  Signature *signature;
  unsigned char compact_signature[COMPACT_SIG_SIZE_BYTES];

  TypedData_Get_Struct(self, Signature, &Signature_DataType, signature);

  if (secp256k1_ecdsa_signature_serialize_compact(secp256k1_context_static,
                                                  compact_signature,
                                                  &(signature->sig)) != 1)
  {
    rb_raise(
      Secp256k1_SerializationError_class,
      "unable to compute compact signature"
    );
    return Qnil;
  }

  return rb_str_new((char*)compact_signature, COMPACT_SIG_SIZE_BYTES);
}

#der_encoded ⇒ String

Return Distinguished Encoding Rules (DER) encoded signature data.

Returns:

  • (String) —

    binary string containing DER-encoded signature data.



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# File 'ext/rbsecp256k1/rbsecp256k1.c', line 1019

static VALUE
Signature_der_encoded(VALUE self)
{
  // TODO: Cache value after first computation
  Signature *signature;
  unsigned long der_signature_len;
  unsigned char der_signature[72];

  TypedData_Get_Struct(self, Signature, &Signature_DataType, signature);

  der_signature_len = 72;
  if (secp256k1_ecdsa_signature_serialize_der(secp256k1_context_static,
                                              der_signature,
                                              &der_signature_len,
                                              &(signature->sig)) != 1)
  {
    rb_raise(
      Secp256k1_SerializationError_class,
      "could not compute DER encoded signature"
    );
    return Qnil;
  }

  return rb_str_new((char*)der_signature, der_signature_len);
}

#normalized ⇒ Array

Returns the normalized lower-S form of this signature.

This can be useful when importing signatures generated by other applications that may not be normalized. Non-normalized signatures are potentially forgeable.

Returns:

  • (Array) —

    first element is a boolean that is true if the signature was normalized, false otherwise. The second element is a Signature object corresponding to the normalized signature.



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# File 'ext/rbsecp256k1/rbsecp256k1.c', line 1084

static VALUE
Signature_normalized(VALUE self)
{
  VALUE result_sig;
  VALUE was_normalized;
  VALUE result;
  Signature *signature;
  Signature *normalized_signature;

  TypedData_Get_Struct(self, Signature, &Signature_DataType, signature);
  result_sig = Signature_alloc(Secp256k1_Signature_class);
  TypedData_Get_Struct(
    result_sig, Signature, &Signature_DataType, normalized_signature
  );

  was_normalized = Qfalse;
  if (secp256k1_ecdsa_signature_normalize(
        secp256k1_context_static,
        &(normalized_signature->sig),
        &(signature->sig)) == 1)
  {
    was_normalized = Qtrue;
  }

  result = rb_ary_new2(2);
  rb_ary_push(result, was_normalized);
  rb_ary_push(result, result_sig);

  return result;
}