From e5891a82c39997b65ce9ff90eb6120db7bedd399 Mon Sep 17 00:00:00 2001 From: NIIBE Yutaka Date: Thu, 6 Aug 2015 17:00:41 +0900 Subject: Curve25519 support. * agent/cvt-openpgp.c (get_keygrip): Handle Curve25519. (convert_secret_key, convert_transfer_key): Ditto. * common/openpgp-oid.c (oidtable): Add Curve25519. (oid_crv25519, openpgp_oid_is_crv25519): New. * common/util.h (openpgp_oid_is_crv25519): New. * g10/ecdh.c (pk_ecdh_encrypt_with_shared_point): Handle the case with Montgomery curve which uses x-only coordinate. * g10/keygen.c (gen_ecc): Handle Curve25519. (ask_curve): Change the API and second arg is to return subkey algo. (generate_keypair, generate_subkeypair): Follow chage of ask_curve. * g10/keyid.c (keygrip_from_pk): Handle Curve25519. * g10/pkglue.c (pk_encrypt): Handle Curve25519. * g10/pubkey-enc.c (get_it): Handle the case with Montgomery curve. * scd/app-openpgp.c (ECC_FLAG_DJB_TWEAK): New. (send_key_attr): Work with general ECC, Ed25519, and Curve25519. (get_public_key): Likewise. (ecc_writekey): Handle flag_djb_tweak. -- When libgcrypt has Curve25519, GnuPG now supports Curve25519. --- common/openpgp-oid.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) (limited to 'common/openpgp-oid.c') diff --git a/common/openpgp-oid.c b/common/openpgp-oid.c index af91bb1aa..afda37605 100644 --- a/common/openpgp-oid.c +++ b/common/openpgp-oid.c @@ -45,6 +45,7 @@ static struct { const char *alias; /* NULL or alternative name of the curve. */ } oidtable[] = { + { "Curve25519", "1.3.6.1.4.1.3029.1.5.1", 255, "crv25519" }, { "Ed25519", "1.3.6.1.4.1.11591.15.1", 255, "ed25519" }, { "NIST P-256", "1.2.840.10045.3.1.7", 256, "nistp256" }, @@ -65,6 +66,10 @@ static struct { static const char oid_ed25519[] = { 0x09, 0x2b, 0x06, 0x01, 0x04, 0x01, 0xda, 0x47, 0x0f, 0x01 }; +/* The OID for Curve25519 in OpenPGP format. */ +static const char oid_crv25519[] = + { 0x0a, 0x2b, 0x06, 0x01, 0x04, 0x01, 0x97, 0x55, 0x01, 0x05, 0x01 }; + /* Helper for openpgp_oid_from_str. */ static size_t @@ -291,6 +296,22 @@ openpgp_oid_is_ed25519 (gcry_mpi_t a) } +int +openpgp_oid_is_crv25519 (gcry_mpi_t a) +{ + const unsigned char *buf; + unsigned int nbits; + size_t n; + + if (!a || !gcry_mpi_get_flag (a, GCRYMPI_FLAG_OPAQUE)) + return 0; + + buf = gcry_mpi_get_opaque (a, &nbits); + n = (nbits+7)/8; + return (n == DIM (oid_crv25519) + && !memcmp (buf, oid_crv25519, DIM (oid_crv25519))); +} + /* Map the Libgcrypt ECC curve NAME to an OID. If R_NBITS is not NULL store the bit size of the curve there. Returns NULL for unknown -- cgit v1.2.3