1 files changed, 20 insertions, 5 deletions

diff --git a/dh.c b/dh.c
index 78e230b9f..b76605325 100644
--- a/dh.c
+++ b/dh.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: dh.c,v 1.44 2006/11/07 13:02:07 markus Exp $ */
+/* $OpenBSD: dh.c,v 1.47 2008/06/26 09:19:39 djm Exp $ */
 /*
  * Copyright (c) 2000 Niels Provos.  All rights reserved.
  *
@@ -46,6 +46,7 @@ parse_prime(int linenum, char *line, struct dhgroup *dhg)
         char *cp, *arg;
         char *strsize, *gen, *prime;
         const char *errstr = NULL;
+        long long n;
 
         cp = line;
         if ((arg = strdelim(&cp)) == NULL)
@@ -62,12 +63,24 @@ parse_prime(int linenum, char *line, struct dhgroup *dhg)
         arg = strsep(&cp, " "); /* type */
         if (cp == NULL || *arg == '\0')
                 goto fail;
+        /* Ensure this is a safe prime */
+        n = strtonum(arg, 0, 5, &errstr);
+        if (errstr != NULL || n != MODULI_TYPE_SAFE)
+                goto fail;
         arg = strsep(&cp, " "); /* tests */
         if (cp == NULL || *arg == '\0')
                 goto fail;
+        /* Ensure prime has been tested and is not composite */
+        n = strtonum(arg, 0, 0x1f, &errstr);
+        if (errstr != NULL ||
+            (n & MODULI_TESTS_COMPOSITE) || !(n & ~MODULI_TESTS_COMPOSITE))
+                goto fail;
         arg = strsep(&cp, " "); /* tries */
         if (cp == NULL || *arg == '\0')
                 goto fail;
+        n = strtonum(arg, 0, 1<<30, &errstr);
+        if (errstr != NULL || n == 0)
+                goto fail;
         strsize = strsep(&cp, " "); /* size */
         if (cp == NULL || *strsize == '\0' ||
             (dhg->size = (u_int)strtonum(strsize, 0, 64*1024, &errstr)) == 0 ||
@@ -153,7 +166,7 @@ choose_dh(int min, int wantbits, int max)
         }
 
         linenum = 0;
-        which = arc4random() % bestcount;
+        which = arc4random_uniform(bestcount);
         while (fgets(line, sizeof(line), f)) {
                 if (!parse_prime(linenum, line, &dhg))
                         continue;
@@ -185,7 +198,7 @@ dh_pub_is_valid(DH *dh, BIGNUM *dh_pub)
         BIGNUM *tmp;
 
         if (dh_pub->neg) {
-                logit("invalid public DH value: negativ");
+                logit("invalid public DH value: negative");
                 return 0;
         }
         if (BN_cmp(dh_pub, BN_value_one()) != 1) {      /* pub_exp <= 1 */
@@ -193,8 +206,10 @@ dh_pub_is_valid(DH *dh, BIGNUM *dh_pub)
                 return 0;
         }
 
-        if ((tmp = BN_new()) == NULL)
-                return (-1);
+        if ((tmp = BN_new()) == NULL) {
+                error("%s: BN_new failed", __func__);
+                return 0;
+        }
         if (!BN_sub(tmp, dh->p, BN_value_one()) ||
             BN_cmp(dh_pub, tmp) != -1) {                /* pub_exp > p-2 */
                 BN_clear_free(tmp);