X-Git-Url: https://git.distorted.org.uk/u/mdw/putty/blobdiff_plain/e557416818242c2e8b14ec03d321740fd83619e4..ded53fce5af6818acc2da88653b56c5c94377b8e:/sshdh.c

diff --git a/sshdh.c b/sshdh.c
index d556a252..dabed52a 100644
--- a/sshdh.c
+++ b/sshdh.c
@@ -68,39 +68,19 @@ Bignum dh_create_e(void) {
 
     x = newbn(Q[0]);
 
-    tryagain:
-
-    /*
-     * Create a potential x, by ANDing a string of random bytes
-     * with Qmask.
-     */
-    for (i = 1; i <= x[0]; i++)
-        x[i] = ((random_byte() << 8) + random_byte()) & Qmask[i];
-
-    /*
-     * If x <= 1, go round again.
-     */
-    for (i = 2; i <= x[0]; i++)
-        if (x[i] != 0)
-            break;
-    if (i > x[0] && x[1] <= 1)
-        goto tryagain;
-
-    /*
-     * If x >= q, go round again.
-     */
-    for (i = x[0]; i > 0; i--) {
-        if (x[i] > Q[i])
-            goto tryagain;
-        if (x[i] < Q[i])
-            break;
-    }
+    do {
+	/*
+	 * Create a potential x, by ANDing a string of random bytes
+	 * with Qmask.
+	 */
+	for (i = 1; i <= x[0]; i++)
+	    x[i] = ((random_byte() << 8) + random_byte()) & Qmask[i];
+    } while (bignum_cmp(x, One) <= 0 || bignum_cmp(x, Q) >= 0);
 
     /*
      * Done. Now compute e = g^x mod p.
      */
-    e = newbn(P[0]);
-    modpow(G, x, P, e);
+    e = modpow(G, x, P);
 
     return e;
 }
@@ -109,7 +89,5 @@ Bignum dh_create_e(void) {
  * DH stage 2: given a number f, compute K = f^x mod p.
  */
 Bignum dh_find_K(Bignum f) {
-    Bignum K = newbn(P[0]);
-    modpow(f, x, P, K);
-    return K;
+    return modpow(f, x, P);
 }