Add scripts to generate simple test data for certificate verification.

net/data/verify_certificate_chain_unittest/generate-basic-constraints-pathlen-0-self-issued.py

Index: net/data/verify_certificate_chain_unittest/generate-basic-constraints-pathlen-0-self-issued.py
diff --git a/net/data/verify_certificate_chain_unittest/generate-basic-constraints-pathlen-0-self-issued.py b/net/data/verify_certificate_chain_unittest/generate-basic-constraints-pathlen-0-self-issued.py
new file mode 100755
index 0000000000000000000000000000000000000000..d68d31c25cf0b6b4ae9f5bcae98f51aab125accc
--- /dev/null
+++ b/net/data/verify_certificate_chain_unittest/generate-basic-constraints-pathlen-0-self-issued.py
@@ -0,0 +1,41 @@
+#!/usr/bin/python
+# Copyright (c) 2015 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import os
+import sys
+
+sys.path.insert(0, os.path.dirname(__file__))
+import common
+
+description = """Certificate chain with 2 intermediaries. The first

[mattm, 2015/10/29 01:47:18]

Could use a regular doc string, and __doc__ to access it.

[eroman, 2015/10/31 00:34:25]

Done (neato)

+intermediary has a basic constraints path length of 0. The second one is
+self-issued so does not count against the path length."""
+
+common.Init(__file__)
+
+# Self-signed root certificate (part of trust store).
+root = common.CreateSelfSignedRootCertificate('Root')
+
+# Intermediary with pathlen 0
+intermediary1 = common.CreateIntermediaryCertificate('Intermediary', root)
+intermediary1.GetExtensions().SetProperty('basicConstraints',
+                                          'critical,CA:true,pathlen:0')
+
+# Another intermediary (with the same pathlen restriction).
+# Note that this is self-issued but NOT self-signed.
+intermediary2 = common.CreateIntermediaryCertificate('Intermediary',
+                                                     intermediary1)
+intermediary2.GetExtensions().SetProperty('basicConstraints',
+                                          'critical,CA:true,pathlen:0')
+
+# Target certificate.
+target = common.CreateEndEntityCertificate('Target', intermediary2)
+
+chain = [target, intermediary2, intermediary1]
+trusted = [root]
+time = common.DEFAULT_TIME
+verify_result = True
+
+common.WriteTestFile(description, chain, trusted, time, verify_result)