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 f27844e..e96e11f 100644 (file)
--- 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);
 }