common: New function openpgp_is_curve_supported.

* common/openpgp-oid.c: Include openpgpdefs.h.
(oidtable): Add field pubkey_algo.
(openpgp_is_curve_supported): New.
--

Signed-off-by: Werner Koch <wk@gnupg.org>
This commit is contained in:
Werner Koch 2016-06-02 15:10:52 +02:00
parent c9f9fabdcc
commit 072acb69be
No known key found for this signature in database
GPG Key ID: E3FDFF218E45B72B
2 changed files with 31 additions and 4 deletions

View File

@ -35,7 +35,7 @@
#include <assert.h>
#include "util.h"
#include "openpgpdefs.h"
/* A table with all our supported OpenPGP curves. */
static struct {
@ -43,10 +43,11 @@ static struct {
const char *oidstr; /* IETF formatted OID. */
unsigned int nbits; /* Nominal bit length of the curve. */
const char *alias; /* NULL or alternative name of the curve. */
int pubkey_algo; /* Required OpenPGP algo or 0 for ECDSA/ECDH. */
} oidtable[] = {
{ "Curve25519", "1.3.6.1.4.1.3029.1.5.1", 255, "cv25519" },
{ "Ed25519", "1.3.6.1.4.1.11591.15.1", 255, "ed25519" },
{ "Curve25519", "1.3.6.1.4.1.3029.1.5.1", 255, "cv25519", PUBKEY_ALGO_ECDH },
{ "Ed25519", "1.3.6.1.4.1.11591.15.1", 255, "ed25519", PUBKEY_ALGO_EDDSA },
{ "NIST P-256", "1.2.840.10045.3.1.7", 256, "nistp256" },
{ "NIST P-384", "1.3.132.0.34", 384, "nistp384" },
@ -408,3 +409,29 @@ openpgp_enum_curves (int *iterp)
*iterp = idx;
return NULL;
}
/* Return the Libgcrypt name for for the gpg curve NAME if supported.
* If R_ALGO is not NULL the required OpenPGP public key algo or 0 is
* stored at that address. NULL is returned if the curev is not
* supported. */
const char *
openpgp_is_curve_supported (const char *name, int *r_algo)
{
int idx;
if (r_algo)
*r_algo = 0;
for (idx = 0; idx < DIM (oidtable) && oidtable[idx].name; idx++)
{
if (!strcmp (name, (oidtable[idx].alias? oidtable[idx].alias
/**/ : oidtable[idx].name))
&& curve_supported_p (oidtable[idx].name))
{
if (r_algo)
*r_algo = oidtable[idx].pubkey_algo;
return oidtable[idx].name;
}
}
return NULL;
}

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@ -214,7 +214,7 @@ int openpgp_oid_is_crv25519 (gcry_mpi_t a);
const char *openpgp_curve_to_oid (const char *name, unsigned int *r_nbits);
const char *openpgp_oid_to_curve (const char *oid, int canon);
const char *openpgp_enum_curves (int *idxp);
const char *openpgp_is_curve_supported (const char *name, int *r_algo);
/*-- homedir.c --*/