From cca0e561d66832a14ce422a48e7cdd6473fe0f97 Mon Sep 17 00:00:00 2001
From: Christian Decker <decker.christian@gmail.com>
Date: Thu, 27 Apr 2017 14:48:34 +0200
Subject: [PATCH] sphinx: Added unit-testing mode to test_sphinx

Currently hidden behind the `--unit` flag. Tests the onion reply
against the test vectors.
---
 test/test_sphinx.c | 93 +++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 91 insertions(+), 2 deletions(-)

diff --git a/test/test_sphinx.c b/test/test_sphinx.c
index 26b3f9235..a2fc56c37 100644
--- a/test/test_sphinx.c
+++ b/test/test_sphinx.c
@@ -10,12 +10,96 @@
 #include <unistd.h>
 
 #include "lightningd/sphinx.h"
+#include "utils.h"
 
 secp256k1_context *secp256k1_ctx;
 
+/* Create an onionreply with the test vector parameters and check that
+ * we match the test vectors and that we can also unwrap it. */
+static void run_unit_tests(void)
+{
+	tal_t *tmpctx = tal_tmpctx(NULL);
+	struct onionreply *oreply;
+	u8 *reply;
+	u8 *raw = tal_hexdata(tmpctx, "2002", 4);
+
+	/* Shared secrets we already have from the forward path */
+	char *secrets[] = {
+	    "53eb63ea8a3fec3b3cd433b85cd62a4b145e1dda09391b348c4e1cd36a03ea66",
+	    "a6519e98832a0b179f62123b3567c106db99ee37bef036e783263602f3488fae",
+	    "3a6b412548762f0dbccce5c7ae7bb8147d1caf9b5471c34120b30bc9c04891cc",
+	    "21e13c2d7cfe7e18836df50872466117a295783ab8aab0e7ecc8c725503ad02d",
+	    "b5756b9b542727dbafc6765a49488b023a725d631af688fc031217e90770c328",
+	};
+	u8 *ss[] = {
+	    tal_hexdata(tmpctx, secrets[0], 64),
+	    tal_hexdata(tmpctx, secrets[1], 64),
+	    tal_hexdata(tmpctx, secrets[2], 64),
+	    tal_hexdata(tmpctx, secrets[3], 64),
+	    tal_hexdata(tmpctx, secrets[4], 64),
+	};
+
+	u8 *intermediates[] = {
+	    tal_hexdata(tmpctx, "500d8596f76d3045bfdbf99914b98519fe76ea139a47d1"
+				"ab34da8730a01515e63a04819d896f45610741c83ad40b"
+				"7712aefaddec8c6baf7325d92ea4ca4d1df8bce517f7e5"
+				"4554608bf2bd8071a4f52a7a2f7ffbb1413edad81eeea5"
+				"785aa9d990f2865dc23b4bc3c301a94eec4eabebca66be"
+				"5cf638f693ec256aec514620cc28ee4a94bd9565bc4d49"
+				"62b9d3641d4278fb319ed2b84de5",
+			304),
+	    tal_hexdata(tmpctx, "669478a3ddf9ba4049df8fa51f73ac712b9c20389b5fb1"
+				"85663f16115045868ab7dd8db956128dae8857add94e67"
+				"02fb4c3a4de22e2e669e1ed926b04447fc73034bb730f4"
+				"932acd62727b75348a648a1128744657ca6a4e713b9b64"
+				"6c3ca66cac02cdab44dd3439890ef3aaf61708714f7375"
+				"349b8da541b2548d452d84de7084bb95b3ac2345201d62"
+				"4d31f4d52078aa0fa05a88b4e202",
+			304),
+	    tal_hexdata(tmpctx, "6984b0ccd86f37995857363df13670acd064bfd132c517"
+				"b23a7dfb4470e7d16aff98e25d41d3dfb7466e74f81b3e"
+				"545563cdd8f5524dae873de61d7bdfccd496af2584930d"
+				"2b566b4f8d3881f8c043df92224f38cf094cfc09d92655"
+				"989531524593ec6d6caec1863bdfaa79229b5020acc034"
+				"cd6deeea1021c50586947b9b8e6faa83b81fbfa6133c0a"
+				"f5d6b07c017f7158fa94f0d206ba",
+			304),
+	    tal_hexdata(tmpctx, "08cd44478211b8a4370ab1368b5ffe8c9c92fb8398715f"
+				"fdcba31d358e842c21a0839ab361940011585323930fa5"
+				"b9fae0c85770a2279ff59ec427ad1bbff9001c0cd14970"
+				"04bd2a0f68b50704cf6d6a4bf3c8b6a0833399a24b3456"
+				"961ba00736785112594f65b6b2d44d9f5ea4e49b5e1ec2"
+				"af978cbe31c67114440ac51a62081df0ed46d4a3df295d"
+				"a0b0fe25c0115019f03f15ec86fa",
+			304),
+	    tal_hexdata(tmpctx, "69b1e5a3e05a7b5478e6529cd1749fdd8c66da6ffa31d2"
+				"eb0f2dbbf4394713c6a8c9b16ab5f12fd45edd73c1b0c8"
+				"b33002df376801ff58aaa94000bf8a86f92620f343baef"
+				"38a580102395ae3abf9128d1047a0736ff9b83d456740e"
+				"bbb4aeb3aa9737f18fb4afb4aa074fb26c4d702f429688"
+				"88550a3bded8c05247e045b866baef0499f079fdaeef65"
+				"38f31d44deafffdfd3afa2fb4ca9",
+			304),
+	};
+
+	reply = create_onionreply(tmpctx, ss[4], raw);
+	for (int i = 4; i >= 0; i--) {
+		printf("input_packet %s\n", tal_hex(tmpctx, reply));
+		reply = wrap_onionreply(tmpctx, ss[i], reply);
+		printf("obfuscated_packet %s\n", tal_hex(tmpctx, reply));
+		assert(memcmp(reply, intermediates[i], tal_len(reply)) == 0);
+	}
+
+	oreply = unwrap_onionreply(tmpctx, ss, 5, reply);
+	printf("unwrapped %s\n", tal_hex(tmpctx, oreply->msg));
+	assert(memcmp(raw, oreply->msg, tal_len(raw)) == 0);
+
+	tal_free(tmpctx);
+}
+
 int main(int argc, char **argv)
 {
-	bool generate = false, decode = false;
+	bool generate = false, decode = false, unit = false;
 	const tal_t *ctx = talz(NULL, tal_t);
 	u8 assocdata[32];
 	memset(assocdata, 'B', sizeof(assocdata));
@@ -34,10 +118,15 @@ int main(int argc, char **argv)
 	opt_register_noarg("--decode",
 			   opt_set_bool, &decode,
 			   "Decode onion from stdin given the private key");
+	opt_register_noarg("--unit",
+			   opt_set_bool, &unit,
+			   "Run unit tests against test vectors");
 
 	opt_parse(&argc, argv, opt_log_stderr_exit);
 
-	if (generate) {
+	if (unit) {
+		run_unit_tests();
+	} else if (generate) {
 		int num_hops = argc - 1;
 		struct pubkey *path = tal_arr(ctx, struct pubkey, num_hops);
 		u8 privkeys[argc - 1][32];