KCC: Simplify RNG seeding logic, dropping the default value

There is no particular justification for the previous default, other
than being deterministic makes testing more reliable. The algorithms
using randomness do not assume determinism.

Signed-off-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Reviewed-by: Garming Sam <garming@catalyst.net.nz>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>

diff --git a/source4/scripting/bin/samba_kcc b/source4/scripting/bin/samba_kcc
index 889e47b33765f01b498d137c617d3c9e122e6b28..0caba79758c05f793fc83e676b5005aaf7bbfa1e 100755 (executable)
--- a/source4/scripting/bin/samba_kcc
+++ b/source4/scripting/bin/samba_kcc
@@ -51,6 +51,8 @@ import logging
 from samba.kcc.debug import logger, DEBUG, DEBUG_FN
 from samba.kcc import KCC
 
+# If DEFAULT_RNG_SEED is None, /dev/urandom or system time is used.
+DEFAULT_RNG_SEED = None
 
 def test_all_reps_from(lp, creds, unix_now, rng_seed=None):
     """Run the KCC from all DSAs in read-only mode
@@ -86,7 +88,7 @@ def test_all_reps_from(lp, creds, unix_now, rng_seed=None):
     vertex_colours = []
 
     for dsa_dn in dsas:
-        if rng_seed:
+        if rng_seed is not None:
             random.seed(rng_seed)
         kcc = KCC(unix_now, readonly=True,
                   verify=opts.verify, debug=opts.debug,
@@ -185,7 +187,7 @@ parser.add_option("--dot-file-dir", default=None,
 
 parser.add_option("--seed",
                   help="random number seed",
-                  type=int)
+                  type=int, default=DEFAULT_RNG_SEED)
 
 parser.add_option("--importldif",
                   help="import topology ldif file",
@@ -248,11 +250,7 @@ elif opts.readonly:
 else:
     logger.setLevel(logging.WARNING)
 
-# initialize seed from optional input parameter
-if opts.seed:
-    random.seed(opts.seed)
-else:
-    random.seed(0xACE5CA11)
+random.seed(opts.seed)
 
 if opts.now:
     for timeformat in ("%Y%m%d%H%M%S%Z", "%Y%m%d%H%M%S"):
@@ -277,8 +275,7 @@ if opts.dburl is None:
 
 if opts.test_all_reps_from:
     opts.readonly = True
-    rng_seed = opts.seed or 0xACE5CA11
-    test_all_reps_from(lp, creds, unix_now, rng_seed=rng_seed)
+    test_all_reps_from(kcc, lp, creds, unix_now, rng_seed=opts.seed)
     sys.exit()
 
 # Instantiate Knowledge Consistency Checker and perform run