X-Git-Url: https://git.distorted.org.uk/u/mdw/catacomb/blobdiff_plain/02d7884df1f33c9c7dc3a14c4b1a5f520ebe090a..5c3f75ec49019d160806489824fc76652a2ef444:/ec-info.c

diff --git a/ec-info.c b/ec-info.c
index 0805c26..4f852c2 100644
--- a/ec-info.c
+++ b/ec-info.c
@@ -1,6 +1,6 @@
 /* -*-c-*-
  *
- * $Id: ec-info.c,v 1.4 2004/04/03 03:32:05 mdw Exp $
+ * $Id: ec-info.c,v 1.7 2004/04/17 09:58:37 mdw Exp $
  *
  * Elliptic curve information management
  *
@@ -27,29 +27,6 @@
  * MA 02111-1307, USA.
  */
 
-/*----- Revision history --------------------------------------------------* 
- *
- * $Log: ec-info.c,v $
- * Revision 1.4  2004/04/03 03:32:05  mdw
- * General robustification.
- *
- * Revision 1.3  2004/04/01 21:28:41  mdw
- * Normal basis support (translates to poly basis internally).  Rewrite
- * EC and prime group table generators in awk, so that they can reuse data
- * for repeated constants.
- *
- * Revision 1.2  2004/04/01 12:50:09  mdw
- * Add cyclic group abstraction, with test code.  Separate off exponentation
- * functions for better static linking.  Fix a buttload of bugs on the way.
- * Generally ensure that negative exponents do inversion correctly.  Add
- * table of standard prime-field subgroups.  (Binary field subgroups are
- * currently unimplemented but easy to add if anyone ever finds a good one.)
- *
- * Revision 1.1  2004/03/27 17:54:11  mdw
- * Standard curves and curve checking.
- *
- */
-
 /*----- Header files ------------------------------------------------------*/
 
 #include "ec.h"
@@ -395,11 +372,6 @@ static const char *primecheck(const ec_info *ei, grand *gr)
 
   if (!pgen_primep(ei->r, gr)) return ("generator order not prime");
 
-  /* --- Check %$0 < h \le 4$% --- */
-
-  if (MP_CMP(ei->h, <, MP_ONE) || MP_CMP(ei->h, >, MP_FOUR))
-    return ("cofactor out of range");
-
   /* --- Check %$h = \lfloor (\sqrt{p} + 1)^2/r \rlfoor$% --- *
    *
    * This seems to work with the approximate-sqrt in the library, but might
@@ -444,6 +416,11 @@ static const char *primecheck(const ec_info *ei, grand *gr)
   MP_DROP(x);
   if (i) return ("curve is weak");
 
+  /* --- Check %$0 < h \le 4$% --- */
+
+  if (MP_CMP(ei->h, <, MP_ONE) || MP_CMP(ei->h, >, MP_FOUR))
+    return ("cofactor out of range");
+
   /* --- Done --- */
 
   return (0);
@@ -482,11 +459,6 @@ static const char *bincheck(const ec_info *ei, grand *gr)
 
   if (!pgen_primep(ei->r, gr)) return ("generator order not prime");
 
-  /* --- Check %$0 < h \le 4$% --- */
-
-  if (MP_CMP(ei->h, <, MP_ONE) || MP_CMP(ei->h, >, MP_FOUR))
-    return ("cofactor out of range");
-
   /* --- Check %$h = \lfloor (\sqrt{2^m} + 1)^2/r \rlfoor$% --- *
    *
    * This seems to work with the approximate-sqrt in the library, but might
@@ -528,6 +500,11 @@ static const char *bincheck(const ec_info *ei, grand *gr)
   MP_DROP(x);
   if (i) return ("curve is weak");
 
+  /* --- Check %$0 < h \le 4$% --- */
+
+  if (MP_CMP(ei->h, <, MP_ONE) || MP_CMP(ei->h, >, MP_FOUR))
+    return ("cofactor out of range");
+
   /* --- Done --- */
 
   return (0);
@@ -548,29 +525,48 @@ const char *ec_checkinfo(const ec_info *ei, grand *gr)
 
 #include "fibrand.h"
 
-int main(void)
+int main(int argc, char *argv[])
 {
   const ecentry *ee;
   const char *e;
   int ok = 1;
+  int i;
   grand *gr;
 
   gr = fibrand_create(0);
-  fputs("checking standard curves: ", stdout);
-  for (ee = ectab; ee->name; ee++) {
-    ec_info ei;
-    getinfo(&ei, ee->data);
-    e = ec_checkinfo(&ei, gr);
-    ec_freeinfo(&ei);
-    if (e) {
-      fprintf(stderr, "\n*** curve %s fails: %s\n", ee->name, e);
-      ok = 0;
+  if (argc > 1) {
+    for (i = 1; i < argc; i++) {
+      ec_info ei;
+      if ((e = ec_getinfo(&ei, argv[i])) != 0)
+	fprintf(stderr, "bad curve spec `%s': %s", argv[i], e);
+      else {
+	e = ec_checkinfo(&ei, gr);
+	ec_freeinfo(&ei);
+	if (!e)
+	  printf("OK %s\n", argv[i]);
+	else {
+	  printf("BAD %s: %s\n", argv[i], e);
+	  ok = 0;
+	}
+      }
+    }
+  } else {
+    fputs("checking standard curves: ", stdout);
+    for (ee = ectab; ee->name; ee++) {
+      ec_info ei;
+      getinfo(&ei, ee->data);
+      e = ec_checkinfo(&ei, gr);
+      ec_freeinfo(&ei);
+      if (e) {
+	fprintf(stderr, "\n*** curve %s fails: %s\n", ee->name, e);
+	ok = 0;
+      }
+      putchar('.');
+      fflush(stdout);
     }
-    putchar('.');
-    fflush(stdout);
+    fputs(ok ? " ok\n" : " failed\n", stdout);
   }
   gr->ops->destroy(gr);
-  fputs(ok ? " ok\n" : " failed\n", stdout);
   return (!ok);
 }