From: beck <beck@openbsd.org>
Date: Fri, 18 Apr 2014 17:25:17 +0000 (+0000)
Subject: RAND_xxx considered harmful. use arc4random_buf instead of nasty stuff.
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=856c2beff71442a22c3a438e3c3fba4c8113a7d9;p=openbsd

RAND_xxx considered harmful. use arc4random_buf instead of nasty stuff.
ok tedu@
---

diff --git a/kerberosV/src/lib/krb5/crypto-rand.c b/kerberosV/src/lib/krb5/crypto-rand.c
index f27844e9f7c..e96e11febb2 100644
--- a/kerberosV/src/lib/krb5/crypto-rand.c
+++ b/kerberosV/src/lib/krb5/crypto-rand.c
@@ -33,77 +33,8 @@
 
 #include "krb5_locl.h"
 
-#define ENTROPY_NEEDED 128
-
-static HEIMDAL_MUTEX crypto_mutex = HEIMDAL_MUTEX_INITIALIZER;
-
-static int
-seed_something(void)
-{
-    char buf[1024], seedfile[256];
-
-    /* If there is a seed file, load it. But such a file cannot be trusted,
-       so use 0 for the entropy estimate */
-    if (RAND_file_name(seedfile, sizeof(seedfile))) {
-	int fd;
-	fd = open(seedfile, O_RDONLY | O_BINARY | O_CLOEXEC);
-	if (fd >= 0) {
-	    ssize_t ret;
-	    rk_cloexec(fd);
-	    ret = read(fd, buf, sizeof(buf));
-	    if (ret > 0)
-		RAND_add(buf, ret, 0.0);
-	    close(fd);
-	} else
-	    seedfile[0] = '\0';
-    } else
-	seedfile[0] = '\0';
-
-    /* Calling RAND_status() will try to use /dev/urandom if it exists so
-       we do not have to deal with it. */
-    if (RAND_status() != 1) {
-#ifndef _WIN32
-	krb5_context context;
-	const char *p;
-
-	/* Try using egd */
-	if (!krb5_init_context(&context)) {
-	    p = krb5_config_get_string(context, NULL, "libdefaults",
-				       "egd_socket", NULL);
-	    if (p != NULL)
-		arc4random_buf(p, ENTROPY_NEEDED);
-	    krb5_free_context(context);
-	}
-#else
-	/* TODO: Once a Windows CryptoAPI RAND method is defined, we
-	   can use that and failover to another method. */
-#endif
-    }
-
-    if (RAND_status() == 1)	{
-	/* Update the seed file */
-	if (seedfile[0])
-	    RAND_write_file(seedfile);
-
-	return 0;
-    } else
-	return -1;
-}
-
 KRB5_LIB_FUNCTION void KRB5_LIB_CALL
 krb5_generate_random_block(void *buf, size_t len)
 {
-    static int rng_initialized = 0;
-
-    HEIMDAL_MUTEX_lock(&crypto_mutex);
-    if (!rng_initialized) {
-	if (seed_something())
-	    krb5_abortx(NULL, "Fatal: could not seed the "
-			"random number generator");
-
-	rng_initialized = 1;
-    }
-    HEIMDAL_MUTEX_unlock(&crypto_mutex);
-    if (RAND_bytes(buf, len) <= 0)
-	krb5_abortx(NULL, "Failed to generate random block");
+	arc4random_buf(buf, len);
 }