crypto_ecc_gnsrecord.c File Reference

public key cryptography (ECC) for GNS records (LSD0001) More...

#include "platform.h"
#include <gcrypt.h>
#include <sodium.h>
#include "gnunet_util_lib.h"

Include dependency graph for crypto_ecc_gnsrecord.c:

Go to the source code of this file.

Macros
#define	CURVE   "Ed25519"

Functions
static void	derive_h (const void *pub, size_t pubsize, const char *label, const char *context, struct GNUNET_HashCode *hc)
	Derive the 'h' value for key derivation, where 'h = H(l,P)'. More...
enum GNUNET_GenericReturnValue	GNUNET_CRYPTO_eddsa_sign_derived (const struct GNUNET_CRYPTO_EddsaPrivateKey *pkey, const char *label, const char *context, const struct GNUNET_CRYPTO_EccSignaturePurpose *purpose, struct GNUNET_CRYPTO_EddsaSignature *sig)
	This is a signature function for EdDSA which takes a private key and derives it using the label and context before signing. More...
enum GNUNET_GenericReturnValue	GNUNET_CRYPTO_ecdsa_sign_derived (const struct GNUNET_CRYPTO_EcdsaPrivateKey *priv, const char *label, const char *context, const struct GNUNET_CRYPTO_EccSignaturePurpose *purpose, struct GNUNET_CRYPTO_EcdsaSignature *sig)
	This is a signature function for ECDSA which takes a private key, derives/blinds it and signs the message. More...
struct GNUNET_CRYPTO_EcdsaPrivateKey *	GNUNET_CRYPTO_ecdsa_private_key_derive (const struct GNUNET_CRYPTO_EcdsaPrivateKey *priv, const char *label, const char *context)
	Derive a private key from a given private key and a label. More...
void	GNUNET_CRYPTO_ecdsa_public_key_derive (const struct GNUNET_CRYPTO_EcdsaPublicKey *pub, const char *label, const char *context, struct GNUNET_CRYPTO_EcdsaPublicKey *result)
	Derive a public key from a given public key and a label. More...
void	GNUNET_CRYPTO_eddsa_private_key_derive (const struct GNUNET_CRYPTO_EddsaPrivateKey *priv, const char *label, const char *context, struct GNUNET_CRYPTO_EddsaPrivateScalar *result)
	Derive a private scalar from a given private key and a label. More...
void	GNUNET_CRYPTO_eddsa_public_key_derive (const struct GNUNET_CRYPTO_EddsaPublicKey *pub, const char *label, const char *context, struct GNUNET_CRYPTO_EddsaPublicKey *result)
	Derive a public key from a given public key and a label. More...
void	GNUNET_CRYPTO_eddsa_key_get_public_from_scalar (const struct GNUNET_CRYPTO_EddsaPrivateScalar *priv, struct GNUNET_CRYPTO_EddsaPublicKey *pkey)
	Extract the public key of the given private scalar. More...

Detailed Description

public key cryptography (ECC) for GNS records (LSD0001)

Author

Christian Grothoff

Florian Dold

Martin Schanzenbach

Definition in file crypto_ecc_gnsrecord.c.

Macro Definition Documentation

CURVE

#define CURVE   "Ed25519"

Definition at line 34 of file crypto_ecc_gnsrecord.c.

Function Documentation

derive_h()

static void derive_h ( const void *  pub, size_t  pubsize, const char *  label, const char *  context, struct GNUNET_HashCode *  hc  )

static

Derive the 'h' value for key derivation, where 'h = H(l,P)'.

Parameters

pub	public key for deriviation
pubsize	the size of the public key
label	label for deriviation
context	additional context to use for HKDF of 'h'; typically the name of the subsystem/application
hc	where to write the result

NOTE: While (H)KDF calls this value a salt it is not necessary for it to be a random value. It is more common to use a NULL value here (https://www.rfc-editor.org/rfc/rfc8446#section-7.1) But it is safe either way (See RFC 5869)

Definition at line 48 of file crypto_ecc_gnsrecord.c.

{
  static const char *const salt = "key-derivation";
 
  GNUNET_CRYPTO_kdf (hc,
                     sizeof(*hc),
                     salt,
                     strlen (salt),
                     pub,
                     pubsize,
                     label,
                     strlen (label),
                     context,
                     strlen (context),
                     NULL,
                     0);
}

References context, GNUNET_CRYPTO_kdf(), pub, and salt.

Referenced by GNUNET_CRYPTO_ecdsa_private_key_derive(), GNUNET_CRYPTO_ecdsa_public_key_derive(), GNUNET_CRYPTO_eddsa_private_key_derive(), and GNUNET_CRYPTO_eddsa_public_key_derive().

Here is the call graph for this function:

Here is the caller graph for this function: