From ca6a2d5a870e1e1cea54a67e9330bced4e58f1fe Mon Sep 17 00:00:00 2001
From: "Jeff R. Allen" <jeff.allen@epfl.ch>
Date: Tue, 14 Apr 2020 11:51:56 +0200
Subject: [PATCH] Test vectors.

---
 LowCostDP3T.py | 20 ++++++++++++++++++++
 README.md      | 14 ++++++++++++++
 2 files changed, 34 insertions(+)

diff --git a/LowCostDP3T.py b/LowCostDP3T.py
index 9cd47d2..4173f70 100644
--- a/LowCostDP3T.py
+++ b/LowCostDP3T.py
@@ -277,3 +277,23 @@ def next_day(self):
 
 	def next_epoch(self):
 		self.ctmgr.process_epoch()
+                
+# Generate test vectors
+if __name__ == "__main__":
+        def hex(y):
+                return ''.join( [ "%02x" % x for x in y ] )
+
+        ks = KeyStore()
+        ks.SKt.insert(0, b"\0" * 32)
+        print("sk0", hex(ks.SKt[0]))
+        e = ks.create_ephIDs(ks.SKt[0])
+        print("ephID[0]", hex(e[0]))
+        print("ephID[1]", hex(e[1]))
+        print("ephID[95]", hex(e[95]))
+        
+        ks.rotate_SK()
+        print("sk1", hex(ks.SKt[0]))
+        e = ks.create_ephIDs(ks.SKt[0])
+        print("ephID[0]", hex(e[0]))
+        print("ephID[1]", hex(e[1]))
+        print("ephID[95]", hex(e[95]))
diff --git a/README.md b/README.md
index 537606c..35e3924 100644
--- a/README.md
+++ b/README.md
@@ -32,6 +32,20 @@ and `rotate_ephIDs` which creates the set of `ephIDs` for the new day. These
 methods are straight forward implementations of the description in the
 whitepaper.
 
+LowCostDP3T.py, when run standalone, will generate test vectors to help
+other implementors check their work:
+
+```
+$ python3 ./LowCostDP3T.py 
+sk0 0000000000000000000000000000000000000000000000000000000000000000
+ephID[0] 8fd521e6c47060efcbfdb9b801c30743
+ephID[1] d86e56bb702117b8cf20dc4aadd42310
+ephID[95] f38403173134f2c65682ee799e817ef3
+sk1 66687aadf862bd776c8fc18b8e9f8e20089714856ee233b3902a591d0d5f2925
+ephID[0] fda0fff97c5566886c5afcb0c7333f73
+ephID[1] 1d1ae795488b0ad0e4aba33d4bed3f4a
+ephID[95] b832b76cb203226cd7297f8483c60b76
+```
 
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