gpg: Change format for the key size in --list-key and --edit-key.

* g10/gpg.c (oLegacyListMode, opts, main): Add --legacy-list-mode.
* g10/options.h (struct opt): Add field legacy_list_mode.
* g10/keydb.h (PUBKEY_STRING_SIZE): New.
* g10/keyid.c (pubkey_string): New.
* g10/import.c (import_one, import_secret_one): Use pubkey_string.
* g10/keylist.c (print_seckey_info): Ditto.
(print_pubkey_info, print_card_key_info): Ditto.
(list_keyblock_print): Ditto.
* g10/mainproc.c (list_node): Ditto.
* g10/pkclist.c (do_edit_ownertrust, build_pk_list): Ditto.
* g10/keyedit.c (show_key_with_all_names): Ditto.  Also change the
format.
(show_basic_key_info): Ditto.
* common/openpgp-oid.c (openpgp_curve_to_oid): Also allow "ed25519".
(openpgp_oid_to_curve): Downcase "ed25519"
--

For ECC it seems to be better to show the name of the curve and not
just the size of the prime field.  The curve name does not anymore fit
into the "<size><letter>" descriptor (e.g. "2048R") and a fixed length
format does not work either.  Thus the new format uses

   "rsa2048"    - RSA with 2048 bit
   "elg1024"    - Elgamal with 1024 bit
   "ed25519"    - ECC using the curve Ed25519.
   "E_1.2.3.4"  - ECC using the unsupported curve with OID "1.2.3.4".

unless --legacy-list-mode is given.  In does not anymore line up
nicely in columns thus I expect further changes to this new format.

Signed-off-by: Werner Koch <wk@gnupg.org>

1 files changed, 71 insertions, 2 deletions

diff --git a/g10/keyid.c b/g10/keyid.c
index 5fa44ef9c..9ed64a4b5 100644
--- a/g10/keyid.c
+++ b/g10/keyid.c
@@ -1,6 +1,7 @@
 /* keyid.c - key ID and fingerprint handling
  * Copyright (C) 1998, 1999, 2000, 2001, 2003,
  *               2004, 2006, 2010 Free Software Foundation, Inc.
+ * Copyright (C) 2014 Werner Koch
  *
  * This file is part of GnuPG.
  *
@@ -57,13 +58,81 @@ pubkey_letter( int algo )
     case PUBKEY_ALGO_ELGAMAL_E: return 'g' ;
     case PUBKEY_ALGO_ELGAMAL:   return 'G' ;
     case PUBKEY_ALGO_DSA:	return 'D' ;
-    case PUBKEY_ALGO_EDDSA:	return 'E' ;	/* ECC EdDSA (sign only) */
-    case PUBKEY_ALGO_ECDSA:	return 'E' ;	/* ECC DSA (sign only)   */
     case PUBKEY_ALGO_ECDH:	return 'e' ;	/* ECC DH (encrypt only) */
+    case PUBKEY_ALGO_ECDSA:	return 'E' ;	/* ECC DSA (sign only)   */
+    case PUBKEY_ALGO_EDDSA:	return 'E' ;	/* ECC EdDSA (sign only) */
     default: return '?';
     }
 }
 
+/* Return a string describing the public key algorithm and the
+   keysize.  For elliptic curves the functions prints the name of the
+   curve because the keysize is a property of the curve.  The string
+   is copied to the supplied buffer up a length of BUFSIZE-1.
+   Examples for the output are:
+
+   "rsa2048"  - RSA with 2048 bit
+   "elg1024"  - Elgamal with 1024 bit
+   "ed25519"  - ECC using the curve Ed25519.
+   "E_1.2.3.4"  - ECC using the unsupported curve with OID "1.2.3.4".
+   "E_1.3.6.1.4.1.11591.2.12242973" ECC with a bogus OID.
+   "unknown_N"  - Unknown OpenPGP algorithm N.
+
+   If the option --legacy-list-mode is active, the output use the
+   legacy format:
+
+   "2048R" - RSA with 2048 bit
+   "1024g" - Elgamal with 1024 bit
+   "256E"  - ECDSA using a curve with 256 bit
+
+   The macro PUBKEY_STRING_SIZE may be used to allocate a buffer with
+   a suitable size.*/
+char *
+pubkey_string (PKT_public_key *pk, char *buffer, size_t bufsize)
+{
+  const char *prefix = NULL;
+
+  if (opt.legacy_list_mode)
+    {
+      snprintf (buffer, bufsize, "%4u%c",
+                nbits_from_pk (pk), pubkey_letter (pk->pubkey_algo));
+      return buffer;
+    }
+
+  switch (pk->pubkey_algo)
+    {
+    case PUBKEY_ALGO_RSA:
+    case PUBKEY_ALGO_RSA_E:
+    case PUBKEY_ALGO_RSA_S:	prefix = "rsa"; break;
+    case PUBKEY_ALGO_ELGAMAL_E: prefix = "elg"; break;
+    case PUBKEY_ALGO_DSA:	prefix = "dsa"; break;
+    case PUBKEY_ALGO_ELGAMAL:   prefix = "xxx"; break;
+    case PUBKEY_ALGO_ECDH:
+    case PUBKEY_ALGO_ECDSA:
+    case PUBKEY_ALGO_EDDSA:     prefix = "";    break;
+    }
+
+  if (prefix && *prefix)
+    snprintf (buffer, bufsize, "%s%u", prefix, nbits_from_pk (pk));
+  else if (prefix)
+    {
+      char *curve = openpgp_oid_to_str (pk->pkey[0]);
+      const char *name = openpgp_oid_to_curve (curve);
+
+      if (*name && *name != '?')
+        snprintf (buffer, bufsize, "%s", name);
+      else if (curve)
+        snprintf (buffer, bufsize, "E_%s", curve);
+      else
+        snprintf (buffer, bufsize, "E_error");
+      xfree (curve);
+    }
+  else
+    snprintf (buffer, bufsize, "unknown_%u", (unsigned int)pk->pubkey_algo);
+
+  return buffer;
+}
+
 
 /* Hash a public key.  This function is useful for v4 fingerprints and
    for v3 or v4 key signing. */