cryptonote: sort tx_extra fields

This removes some small amount of fingerprinting entropy.
There is no consensus rule to require this since this field
is technically free form, and a transaction is free to have
custom data in it.

1 files changed, 84 insertions, 0 deletions

diff --git a/tests/unit_tests/test_tx_utils.cpp b/tests/unit_tests/test_tx_utils.cpp
index 8a9f983e6..55c76c3b6 100644
--- a/tests/unit_tests/test_tx_utils.cpp
+++ b/tests/unit_tests/test_tx_utils.cpp
@@ -33,6 +33,8 @@
 #include <vector>
 
 #include "common/util.h"
+#include "cryptonote_basic/cryptonote_basic.h"
+#include "cryptonote_basic/tx_extra.h"
 #include "cryptonote_core/cryptonote_tx_utils.h"
 
 namespace
@@ -203,3 +205,85 @@ TEST(validate_parse_amount_case, validate_parse_amount)
   r = cryptonote::parse_amount(res, "1 00.00 00");
   ASSERT_FALSE(r);
 }
+
+TEST(sort_tx_extra, empty)
+{
+  std::vector<uint8_t> extra, sorted;
+  ASSERT_TRUE(cryptonote::sort_tx_extra(extra, sorted));
+  ASSERT_EQ(extra, sorted);
+}
+
+TEST(sort_tx_extra, pubkey)
+{
+  std::vector<uint8_t> sorted;
+  const uint8_t extra_arr[] = {1, 30, 208, 98, 162, 133, 64, 85, 83, 112, 91, 188, 89, 211, 24, 131, 39, 154, 22, 228,
+    80, 63, 198, 141, 173, 111, 244, 183, 4, 149, 186, 140, 230};
+  std::vector<uint8_t> extra(&extra_arr[0], &extra_arr[0] + sizeof(extra_arr));
+  ASSERT_TRUE(cryptonote::sort_tx_extra(extra, sorted));
+  ASSERT_EQ(extra, sorted);
+}
+
+TEST(sort_tx_extra, two_pubkeys)
+{
+  std::vector<uint8_t> sorted;
+  const uint8_t extra_arr[] = {1, 30, 208, 98, 162, 133, 64, 85, 83, 112, 91, 188, 89, 211, 24, 131, 39, 154, 22, 228,
+    80, 63, 198, 141, 173, 111, 244, 183, 4, 149, 186, 140, 230,
+    1, 30, 208, 98, 162, 133, 64, 85, 83, 112, 91, 188, 89, 211, 24, 131, 39, 154, 22, 228,
+    80, 63, 198, 141, 173, 111, 244, 183, 4, 149, 186, 140, 230};
+  std::vector<uint8_t> extra(&extra_arr[0], &extra_arr[0] + sizeof(extra_arr));
+  ASSERT_TRUE(cryptonote::sort_tx_extra(extra, sorted));
+  ASSERT_EQ(extra, sorted);
+}
+
+TEST(sort_tx_extra, keep_order)
+{
+  std::vector<uint8_t> sorted;
+  const uint8_t extra_arr[] = {1, 30, 208, 98, 162, 133, 64, 85, 83, 112, 91, 188, 89, 211, 24, 131, 39, 154, 22, 228,
+    80, 63, 198, 141, 173, 111, 244, 183, 4, 149, 186, 140, 230,
+    2, 9, 1, 0, 0, 0, 0, 0, 0, 0, 0};
+  std::vector<uint8_t> extra(&extra_arr[0], &extra_arr[0] + sizeof(extra_arr));
+  ASSERT_TRUE(cryptonote::sort_tx_extra(extra, sorted));
+  ASSERT_EQ(extra, sorted);
+}
+
+TEST(sort_tx_extra, switch_order)
+{
+  std::vector<uint8_t> sorted;
+  const uint8_t extra_arr[] = {2, 9, 1, 0, 0, 0, 0, 0, 0, 0, 0,
+    1, 30, 208, 98, 162, 133, 64, 85, 83, 112, 91, 188, 89, 211, 24, 131, 39, 154, 22, 228,
+    80, 63, 198, 141, 173, 111, 244, 183, 4, 149, 186, 140, 230};
+  const uint8_t expected_arr[] = {1, 30, 208, 98, 162, 133, 64, 85, 83, 112, 91, 188, 89, 211, 24, 131, 39, 154, 22, 228,
+    80, 63, 198, 141, 173, 111, 244, 183, 4, 149, 186, 140, 230,
+    2, 9, 1, 0, 0, 0, 0, 0, 0, 0, 0};
+  std::vector<uint8_t> extra(&extra_arr[0], &extra_arr[0] + sizeof(extra_arr));
+  ASSERT_TRUE(cryptonote::sort_tx_extra(extra, sorted));
+  std::vector<uint8_t> expected(&expected_arr[0], &expected_arr[0] + sizeof(expected_arr));
+  ASSERT_EQ(expected, sorted);
+}
+
+TEST(sort_tx_extra, invalid)
+{
+  std::vector<uint8_t> sorted;
+  const uint8_t extra_arr[] = {1};
+  std::vector<uint8_t> extra(&extra_arr[0], &extra_arr[0] + sizeof(extra_arr));
+  ASSERT_FALSE(cryptonote::sort_tx_extra(extra, sorted));
+}
+
+TEST(sort_tx_extra, invalid_suffix_strict)
+{
+  std::vector<uint8_t> sorted;
+  const uint8_t extra_arr[] = {2, 9, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1};
+  std::vector<uint8_t> extra(&extra_arr[0], &extra_arr[0] + sizeof(extra_arr));
+  ASSERT_FALSE(cryptonote::sort_tx_extra(extra, sorted));
+}
+
+TEST(sort_tx_extra, invalid_suffix_partial)
+{
+  std::vector<uint8_t> sorted;
+  const uint8_t extra_arr[] = {2, 9, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1};
+  const uint8_t expected_arr[] = {2, 9, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1};
+  std::vector<uint8_t> extra(&extra_arr[0], &extra_arr[0] + sizeof(extra_arr));
+  ASSERT_TRUE(cryptonote::sort_tx_extra(extra, sorted, true));
+  std::vector<uint8_t> expected(&expected_arr[0], &expected_arr[0] + sizeof(expected_arr));
+  ASSERT_EQ(sorted, expected);
+}