- (djm) OpenBSD CVS Sync

   - djm@cvs.openbsd.org 2008/04/13 00:22:17
     [dh.c sshd.c]
     Use arc4random_buf() when requesting more than a single word of output
     Use arc4random_uniform() when the desired random number upper bound
     is not a power of two
     ok deraadt@ millert@

diff --git a/ChangeLog b/ChangeLog
index 43bad0f683bebcd7e8d47a739b9c06397dcac8a5..994800c042470db358f58b914838830e96d2e8e3 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -14,6 +14,13 @@
  - (djm) [openbsd-compat/bsd-arc4random.c openbsd-compat/openbsd-compat.c]
      [configure.ac] Implement arc4random_buf(), import implementation of
      arc4random_uniform() from OpenBSD
+ - (djm) OpenBSD CVS Sync
+   - djm@cvs.openbsd.org 2008/04/13 00:22:17
+     [dh.c sshd.c]
+     Use arc4random_buf() when requesting more than a single word of output
+     Use arc4random_uniform() when the desired random number upper bound
+     is not a power of two
+     ok deraadt@ millert@
 
 20080403
  - (djm) [openbsd-compat/bsd-poll.c] Include stdlib.h to avoid compile-

diff --git a/dh.c b/dh.c
index 66858104cb9383916fc4a76409ed94042c446261..0908fcf113798fdb61cc570ff80c90c430158e49 100644 (file)
--- a/dh.c
+++ b/dh.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: dh.c,v 1.45 2007/09/27 00:15:57 ray Exp $ */
+/* $OpenBSD: dh.c,v 1.46 2008/04/13 00:22:17 djm Exp $ */
 /*
  * Copyright (c) 2000 Niels Provos.  All rights reserved.
  *
@@ -153,7 +153,7 @@ 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;

diff --git a/sshd.c b/sshd.c
index 5dfc2b185bf815ce09ac19e27319f21d9ed6845d..796310b03d0c0646f0f0f0e00f73236da05e05aa 100644 (file)
--- a/sshd.c
+++ b/sshd.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: sshd.c,v 1.355 2008/02/14 13:10:31 mbalmer Exp $ */
+/* $OpenBSD: sshd.c,v 1.356 2008/04/13 00:22:17 djm Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -368,9 +368,6 @@ grace_alarm_handler(int sig)
 static void
 generate_ephemeral_server_key(void)
 {
-       u_int32_t rnd = 0;
-       int i;
-
        verbose("Generating %s%d bit RSA key.",
            sensitive_data.server_key ? "new " : "", options.server_key_bits);
        if (sensitive_data.server_key != NULL)
@@ -379,12 +376,7 @@ generate_ephemeral_server_key(void)
            options.server_key_bits);
        verbose("RSA key generation complete.");
 
-       for (i = 0; i < SSH_SESSION_KEY_LENGTH; i++) {
-               if (i % 4 == 0)
-                       rnd = arc4random();
-               sensitive_data.ssh1_cookie[i] = rnd & 0xff;
-               rnd >>= 8;
-       }
+       arc4random_buf(sensitive_data.ssh1_cookie, SSH_SESSION_KEY_LENGTH);
        arc4random_stir();
 }
 
@@ -583,16 +575,14 @@ demote_sensitive_data(void)
 static void
 privsep_preauth_child(void)
 {
-       u_int32_t rnd[256];
+       u_int32_t rnd[256];
        gid_t gidset[1];
-       u_int i;
 
        /* Enable challenge-response authentication for privilege separation */
        privsep_challenge_enable();
 
        arc4random_stir();
-       for (i = 0; i < 256; i++)
-               rnd[i] = arc4random();
+       arc4random_buf(rnd, sizeof(rnd));
        RAND_seed(rnd, sizeof(rnd));
 
        /* Demote the private keys to public keys. */
@@ -666,7 +656,6 @@ static void
 privsep_postauth(Authctxt *authctxt)
 {
        u_int32_t rnd[256];
-       u_int i;
 
 #ifdef DISABLE_FD_PASSING
        if (1) {
@@ -700,8 +689,7 @@ privsep_postauth(Authctxt *authctxt)
        demote_sensitive_data();
 
        arc4random_stir();
-       for (i = 0; i < 256; i++)
-               rnd[i] = arc4random();
+       arc4random_buf(rnd, sizeof(rnd));
        RAND_seed(rnd, sizeof(rnd));
 
        /* Drop privileges */
@@ -803,7 +791,7 @@ drop_connection(int startups)
        p *= startups - options.max_startups_begin;
        p /= options.max_startups - options.max_startups_begin;
        p += options.max_startups_rate;
-       r = arc4random() % 100;
+       r = arc4random_uniform(100);
 
        debug("drop_connection: p %d, r %d", p, r);
        return (r < p) ? 1 : 0;
@@ -1956,7 +1944,6 @@ do_ssh1_kex(void)
        u_char session_key[SSH_SESSION_KEY_LENGTH];
        u_char cookie[8];
        u_int cipher_type, auth_mask, protocol_flags;
-       u_int32_t rnd = 0;
 
        /*
         * Generate check bytes that the client must send back in the user
@@ -1967,12 +1954,7 @@ do_ssh1_kex(void)
         * cookie.  This only affects rhosts authentication, and this is one
         * of the reasons why it is inherently insecure.
         */
-       for (i = 0; i < 8; i++) {
-               if (i % 4 == 0)
-                       rnd = arc4random();
-               cookie[i] = rnd & 0xff;
-               rnd >>= 8;
-       }
+       arc4random_buf(cookie, sizeof(cookie));
 
        /*
         * Send our public key.  We include in the packet 64 bits of random