[src/trunk]: src/sys/opencrypto swcrypto(4): Simplify iv generation logic wit...

[riastradh <riastradh%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/cbf1b8afee6c
branches:  trunk
changeset: 1011014:cbf1b8afee6c
user:      riastradh <riastradh%NetBSD.org@localhost>
date:      Sun Jun 14 23:23:55 2020 +0000

description:
swcrypto(4): Simplify iv generation logic with cprng_fast.

diffstat:

 sys/opencrypto/cryptosoft.c |  24 +++---------------------
 1 files changed, 3 insertions(+), 21 deletions(-)

diffs (45 lines):

diff -r 52d025e913f9 -r cbf1b8afee6c sys/opencrypto/cryptosoft.c
--- a/sys/opencrypto/cryptosoft.c       Sun Jun 14 23:23:12 2020 +0000
+++ b/sys/opencrypto/cryptosoft.c       Sun Jun 14 23:23:55 2020 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: cryptosoft.c,v 1.54 2019/10/12 00:49:30 christos Exp $ */
+/*     $NetBSD: cryptosoft.c,v 1.55 2020/06/14 23:23:55 riastradh Exp $ */
 /*     $FreeBSD: src/sys/opencrypto/cryptosoft.c,v 1.2.2.1 2002/11/21 23:34:23 sam Exp $       */
 /*     $OpenBSD: cryptosoft.c,v 1.35 2002/04/26 08:43:50 deraadt Exp $ */
 
@@ -24,7 +24,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: cryptosoft.c,v 1.54 2019/10/12 00:49:30 christos Exp $");
+__KERNEL_RCSID(0, "$NetBSD: cryptosoft.c,v 1.55 2020/06/14 23:23:55 riastradh Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -112,25 +112,7 @@
                } else if (exf->reinit) {
                        exf->reinit(sw->sw_kschedule, 0, iv);
                } else {
-                       /* Get random IV */
-                       for (i = 0;
-                           i + sizeof (u_int32_t) <= EALG_MAX_BLOCK_LEN;
-                           i += sizeof (u_int32_t)) {
-                               u_int32_t temp = cprng_fast32();
-
-                               memcpy(iv + i, &temp, sizeof(u_int32_t));
-                       }
-                       /*
-                        * What if the block size is not a multiple
-                        * of sizeof (u_int32_t), which is the size of
-                        * what arc4random() returns ?
-                        */
-                       if (EALG_MAX_BLOCK_LEN % sizeof (u_int32_t) != 0) {
-                               u_int32_t temp = cprng_fast32();
-
-                               bcopy (&temp, iv + i,
-                                   EALG_MAX_BLOCK_LEN - i);
-                       }
+                       cprng_fast(iv, EALG_MAX_BLOCK_LEN);
                }
 
                /* Do we need to write the IV */