[git] GCRYPT - branch, master, updated. libgcrypt-1.5.0-372-g03aed1a

by Werner Koch cvs at cvs.gnupg.org
Fri Nov 8 17:43:22 CET 2013


This is an automated email from the git hooks/post-receive script. It was
generated because a ref change was pushed to the repository containing
the project "The GNU crypto library".

The branch, master has been updated
       via  03aed1acec611362285db5156a6b92c91604fba4 (commit)
      from  e241dde1420475459e32608137829e52748d0212 (commit)

Those revisions listed above that are new to this repository have
not appeared on any other notification email; so we list those
revisions in full, below.

- Log -----------------------------------------------------------------
commit 03aed1acec611362285db5156a6b92c91604fba4
Author: Werner Koch <wk at gnupg.org>
Date:   Fri Nov 8 17:41:42 2013 +0100

    ecc: Improve gcry_pk_get_curve.
    
    * cipher/ecc-curves.c (_gcry_ecc_fill_in_curve): Factor some code out
    to ..
    (find_domain_parms_idx): new.
    (_gcry_ecc_get_curve): Find by curve name on error.
    --
    
    This change allows the use of an input with just the curve name which
    can be used to test whether a given curve has been implemented.  Is is
    required because due to the "param" flag change the caller usually
    does not have the key parameters available.
    
    Signed-off-by: Werner Koch <wk at gnupg.org>

diff --git a/cipher/ecc-curves.c b/cipher/ecc-curves.c
index 27d2d8e..12f539a 100644
--- a/cipher/ecc-curves.c
+++ b/cipher/ecc-curves.c
@@ -333,6 +333,36 @@ scanval (const char *string)
 }
 
 
+/* Return the index of the domain_parms table for a curve with NAME.
+   Return -1 if not found.  */
+static int
+find_domain_parms_idx (const char *name)
+{
+  int idx, aliasno;
+
+  /* First check our native curves.  */
+  for (idx = 0; domain_parms[idx].desc; idx++)
+    if (!strcmp (name, domain_parms[idx].desc))
+      return idx;
+
+  /* If not found consult the alias table.  */
+  if (!domain_parms[idx].desc)
+    {
+      for (aliasno = 0; curve_aliases[aliasno].name; aliasno++)
+        if (!strcmp (name, curve_aliases[aliasno].other))
+          break;
+      if (curve_aliases[aliasno].name)
+        {
+          for (idx = 0; domain_parms[idx].desc; idx++)
+            if (!strcmp (curve_aliases[aliasno].name, domain_parms[idx].desc))
+              return idx;
+        }
+    }
+
+  return -1;
+}
+
+
 /* Generate the crypto system setup.  This function takes the NAME of
    a curve or the desired number of bits and stores at R_CURVE the
    parameters of the named curve or those of a suitable curve.  If
@@ -345,49 +375,25 @@ gpg_err_code_t
 _gcry_ecc_fill_in_curve (unsigned int nbits, const char *name,
                          elliptic_curve_t *curve, unsigned int *r_nbits)
 {
-  int idx, aliasno;
+  int idx;
   const char *resname = NULL; /* Set to a found curve name.  */
 
   if (name)
-    {
-      /* First check our native curves.  */
-      for (idx = 0; domain_parms[idx].desc; idx++)
-        if (!strcmp (name, domain_parms[idx].desc))
-          {
-            resname = domain_parms[idx].desc;
-            break;
-          }
-      /* If not found consult the alias table.  */
-      if (!domain_parms[idx].desc)
-        {
-          for (aliasno = 0; curve_aliases[aliasno].name; aliasno++)
-            if (!strcmp (name, curve_aliases[aliasno].other))
-              break;
-          if (curve_aliases[aliasno].name)
-            {
-              for (idx = 0; domain_parms[idx].desc; idx++)
-                if (!strcmp (curve_aliases[aliasno].name,
-                             domain_parms[idx].desc))
-                  {
-                    resname = domain_parms[idx].desc;
-                    break;
-                  }
-            }
-        }
-    }
+    idx = find_domain_parms_idx (name);
   else
     {
       for (idx = 0; domain_parms[idx].desc; idx++)
         if (nbits == domain_parms[idx].nbits
             && domain_parms[idx].model == MPI_EC_WEIERSTRASS)
-          {
-            resname = domain_parms[idx].desc;
-            break;
-          }
+          break;
+      if (!domain_parms[idx].desc)
+        idx = -1;
     }
-  if (!domain_parms[idx].desc)
+  if (idx < 0)
     return GPG_ERR_UNKNOWN_CURVE;
 
+  resname = domain_parms[idx].desc;
+
   /* In fips mode we only support NIST curves.  Note that it is
      possible to bypass this check by specifying the curve parameters
      directly.  */
@@ -440,6 +446,7 @@ _gcry_ecc_fill_in_curve (unsigned int nbits, const char *name,
 const char *
 _gcry_ecc_get_curve (gcry_sexp_t keyparms, int iterator, unsigned int *r_nbits)
 {
+  gpg_err_code_t rc;
   const char *result = NULL;
   elliptic_curve_t E;
   gcry_mpi_t mpi_g = NULL;
@@ -467,10 +474,39 @@ _gcry_ecc_get_curve (gcry_sexp_t keyparms, int iterator, unsigned int *r_nbits)
   /*
    * Extract the curve parameters..
    */
-  if (_gcry_sexp_extract_param (keyparms, NULL, "-pabgn",
-                                &E.p, &E.a, &E.b, &mpi_g, &E.n,
-                                NULL))
+  rc = gpg_err_code (_gcry_sexp_extract_param (keyparms, NULL, "-pabgn",
+                                               &E.p, &E.a, &E.b, &mpi_g, &E.n,
+                                               NULL));
+  if (rc == GPG_ERR_NO_OBJ)
+    {
+      /* This might be the second use case of checking whether a
+         specific curve given by name is supported.  */
+      gcry_sexp_t l1;
+      char *name;
+
+      l1 = gcry_sexp_find_token (keyparms, "curve", 5);
+      if (!l1)
+        goto leave;  /* No curve name parameter.  */
+
+      name = _gcry_sexp_nth_string (l1, 1);
+      gcry_sexp_release (l1);
+      if (!name)
+        goto leave;  /* Name missing or out of core. */
+
+      idx = find_domain_parms_idx (name);
+      gcry_free (name);
+      if (idx >= 0)  /* Curve found.  */
+        {
+          result = domain_parms[idx].desc;
+          if (r_nbits)
+            *r_nbits = domain_parms[idx].nbits;
+        }
+      return result;
+    }
+
+  if (rc)
     goto leave;
+
   if (mpi_g)
     {
       _gcry_mpi_point_init (&E.G);

-----------------------------------------------------------------------

Summary of changes:
 cipher/ecc-curves.c |  106 ++++++++++++++++++++++++++++++++++-----------------
 1 file changed, 71 insertions(+), 35 deletions(-)


hooks/post-receive
-- 
The GNU crypto library
http://git.gnupg.org


_______________________________________________
Gnupg-commits mailing list
Gnupg-commits at gnupg.org
http://lists.gnupg.org/mailman/listinfo/gnupg-commits




More information about the Gcrypt-devel mailing list