X-Git-Url: https://git.distorted.org.uk/u/mdw/catacomb/blobdiff_plain/4bedc99bbbc9f88129cee9a084fc58cee8237942..d470270aa476e8100eb78b1958ce5dd557983195:/dsig.c

diff --git a/dsig.c b/dsig.c
index 9818367..e591538 100644
--- a/dsig.c
+++ b/dsig.c
@@ -1,6 +1,6 @@
 /* -*-c-*-
  *
- * $Id: dsig.c,v 1.1 2000/06/17 10:54:29 mdw Exp $
+ * $Id: dsig.c,v 1.4 2000/08/04 23:23:44 mdw Exp $
  *
  * Verify signatures on distribuitions of files
  *
@@ -30,6 +30,15 @@
 /*----- Revision history --------------------------------------------------* 
  *
  * $Log: dsig.c,v $
+ * Revision 1.4  2000/08/04 23:23:44  mdw
+ * Various <ctype.h> fixes.
+ *
+ * Revision 1.3  2000/07/15 20:53:23  mdw
+ * More hash functions.  Bug fix in getstring.
+ *
+ * Revision 1.2  2000/07/01 11:27:22  mdw
+ * Use new PKCS#1 padding functions rather than rolling by hand.
+ *
  * Revision 1.1  2000/06/17 10:54:29  mdw
  * Program to generate and verify signatures on multiple files.
  *
@@ -52,17 +61,25 @@
 #include <mLib/report.h>
 #include <mLib/sub.h>
 
-#include "dsa.h"
 #include "getdate.h"
 #include "grand.h"
 #include "ghash.h"
 #include "key.h"
 #include "key-data.h"
-#include "md5.h"
 #include "noise.h"
-#include "rmd160.h"
+
+#include "dsa.h"
 #include "rsa.h"
+#include "pkcs1.h"
+
+#include "md4.h"
+#include "md5.h"
+#include "rmd128.h"
+#include "rmd160.h"
+#include "rmd256.h"
+#include "rmd320.h"
 #include "sha.h"
+#include "tiger.h"
 
 /*----- Digital signature algorithm ---------------------------------------*/
 
@@ -81,6 +98,8 @@ static int dsasign(key *k, const void *m, size_t msz, dstr *d)
     return (e);
   }
   sz = mp_octets(dp.dp.q);
+  if (sz < msz)
+    die(EXIT_FAILURE, "hash function too wide for this signing key");
   DENSURE(d, sz * 2);
   p = d->buf + d->len;
   rand_get(RAND_GLOBAL, p, sz);
@@ -115,11 +134,10 @@ static int dsaverify(key *k, const void *m, size_t msz,
 static int rsasign(key *k, const void *m, size_t msz, dstr *d)
 {
   rsa_priv rp;
+  rsa_privctx rpc;
+  pkcs1 pk = { 0, 0, 0 };
   key_packstruct ks[RSA_PRIVFETCHSZ];
   key_packdef *kp;
-  octet *p;
-  size_t sz;
-  mp *x;
   int e;
 
   kp = key_fetchinit(rsa_privfetch, ks, &rp);
@@ -127,22 +145,10 @@ static int rsasign(key *k, const void *m, size_t msz, dstr *d)
     key_fetchdone(kp);
     return (e);
   }
-  sz = mp_octets(rp.n);
-  if (sz < msz + 11)
-    die(EXIT_FAILURE, "key too small (help!)");
-  DENSURE(d, sz);
-  p = d->buf + d->len;
-  memcpy(p + sz - msz, m, msz);
-  p[0] = 0;
-  p[1] = 1;
-  memset(p + 2, 0xff, sz - msz - 3);
-  p[sz - msz - 1] = 0;
-  memcpy(p + sz - msz, m, msz);
-  x = mp_loadb(MP_NEW, p, sz);
-  x = rsa_decrypt(&rp, x, x, &rand_global);
-  mp_storeb(x, p, sz);
-  d->len += sz;
-  mp_drop(x);
+  rsa_privcreate(&rpc, &rp, &rand_global);
+  if (rsa_sign(&rpc, m, msz, d, pkcs1_sigencode, &pk) < 0)
+    die(EXIT_FAILURE, "internal error in rsasign (key too small?)");
+  rsa_privdestroy(&rpc);
   key_fetchdone(kp);
   return (0);
 }
@@ -151,41 +157,26 @@ static int rsaverify(key *k, const void *m, size_t msz,
 		     const void *s, size_t ssz)
 {
   rsa_pub rp;
+  rsa_pubctx rpc;
+  pkcs1 pk = { 0, 0, 0 };
   key_packstruct ks[RSA_PUBFETCHSZ];
   key_packdef *kp;
-  octet *p;
-  size_t sz;
-  mp *x;
-  mpmont mm;
   int ok = 0;
+  dstr d = DSTR_INIT;
   int e;
-  int i;
 
   kp = key_fetchinit(rsa_pubfetch, ks, &rp);
   if ((e = key_fetch(kp, k)) != 0) {
     key_fetchdone(kp);
     return (e);
   }
-  x = mp_loadb(MP_NEW, s, ssz);
-  mpmont_create(&mm, rp.n);
-  x = mpmont_exp(&mm, x, x, rp.e);
-  mpmont_destroy(&mm);
-  sz = mp_octets(rp.n);
-  p = xmalloc(sz);
-  mp_storeb(x, p, sz);
-  mp_drop(x);
+  rsa_pubcreate(&rpc, &rp);
+  if (rsa_verify(&rpc, s, ssz, &d, pkcs1_sigdecode, &pk) > 0 &&
+      msz == d.len && memcmp(d.buf, m, msz) == 0)
+    ok = 1;
+  dstr_destroy(&d);
+  rsa_pubdestroy(&rpc);
   key_fetchdone(kp);
-  if (msz + 11 >= sz || p[0] != 0 || p[1] != 1 || p[sz - msz - 1] != 0)
-    goto done;
-  for (i = 2; i < sz - msz - 1; i++) {
-    if (p[i] != 0xff)
-      goto done;
-  }
-  if (memcmp(m, p + sz - msz, msz) != 0)
-    goto done;
-  ok = 1;
-done:
-  free(p);
   return (ok);
 }  
 
@@ -199,7 +190,8 @@ typedef struct sig {
 		const void */*s*/, size_t /*ssz*/);
 } sig;
 
-static const gchash *hashtab[] = { &rmd160, &sha, &md5, 0 };
+static const gchash *hashtab[] = {
+  &rmd160, &tiger, &sha, &rmd128, &rmd256, &rmd320, &md5, &md4, 0 };
 static sig sigtab[] = {
   { "dsa", "dsig-dsa", dsasign, dsaverify },
   { "rsa", "dsig-rsa", rsasign, rsaverify },
@@ -357,7 +349,7 @@ static int getstring(FILE *fp, dstr *d, unsigned raw)
 
 again:
   ch = getc(fp);
-  while (isspace((unsigned char)ch))
+  while (isspace(ch))
     ch = getc(fp);
   if (ch == '#') {
     do ch = getc(fp); while (ch != '\n' && ch != EOF);
@@ -389,7 +381,7 @@ again:
       if (ch == EOF)
 	break;
       switch (ch) {
-	case 'a': ch = '\n'; break;
+	case 'a': ch = '\a'; break;
 	case 'b': ch = '\b'; break;
 	case 'f': ch = '\f'; break;
 	case 'n': ch = '\n'; break;
@@ -398,6 +390,7 @@ again:
 	case 'v': ch = '\v'; break;
       }
       DPUTC(d, ch);
+      ch = getc(fp);
       continue;
     }