Add power analysis countermeasures for ECC point multiplications.

The plain PointGFp operator* now uses Montgomery ladder exclusively.

Adds a blinded point multiply algorithm which uses exponent and point
randomization, as well as a Montgomery ladder technique that takes a
random walk of the possible addition chains for k.

1 files changed, 66 insertions, 1 deletions

diff --git a/src/tests/tests.h b/src/tests/tests.h
index 88102f289..14ec5a17b 100644
--- a/src/tests/tests.h
+++ b/src/tests/tests.h
@@ -16,6 +16,7 @@
 #include <string>
 #include <vector>
 #include <iostream>
+#include <sstream>
 
 Botan::RandomNumberGenerator& test_rng();
 
@@ -45,7 +46,69 @@ typedef std::function<size_t ()> test_fn;
 size_t run_tests(const std::vector<std::pair<std::string, test_fn>>& tests);
 void test_report(const std::string& name, size_t ran, size_t failed);
 
-#define TEST(expr, msg) do { if(!(expr)) { ++fails; std::cout << msg; } while(0)
+class Test_State
+   {
+   public:
+      void started(const std::string& /*msg*/) { m_tests_run++; }
+
+      void test_ran(const char* msg);
+
+      void failure(const char* test, const std::string& what_failed)
+         {
+         std::cout << "FAIL " << test << " " << what_failed << "\n";
+         m_tests_failed++;
+         }
+
+      size_t ran() const { return m_tests_run; }
+      size_t failed() const { return m_tests_failed; }
+   private:
+      size_t m_tests_run = 0, m_tests_failed = 0;
+   };
+
+#define BOTAN_CONFIRM_NOTHROW(block) do {                              \
+   try { block }                                                        \
+   catch(std::exception& e) {                                           \
+      _test.failure(BOTAN_CURRENT_FUNCTION, e.what());  \
+   } } while(0)                                                         \
+
+#define BOTAN_TEST(lhs, rhs, msg) do {                                     \
+   _test.started(msg);                                                  \
+   BOTAN_CONFIRM_NOTHROW({                                              \
+      const auto lhs_val = lhs;                                         \
+      const auto rhs_val = rhs;                                         \
+      const bool cmp = lhs_val == rhs_val;                              \
+      if(!cmp)                                                          \
+         {                                                              \
+         std::ostringstream fmt;                                        \
+         fmt << "expr '" << #lhs << " == " << #rhs << "' false, "       \
+             << "actually " << lhs_val << " " << rhs_val                \
+             << " (" << msg << ")";                                     \
+         _test.failure(BOTAN_CURRENT_FUNCTION, fmt.str()); \
+         }                                                              \
+      });                                                               \
+   } while(0)
+
+#define BOTAN_CONFIRM(expr, msg) do {                                     \
+   _test.started(msg);                                                  \
+   BOTAN_CONFIRM_NOTHROW({                                              \
+      const bool expr_val = expr;                                         \
+      if(!expr_val)                                                     \
+         {                                                              \
+         std::ostringstream fmt;                                        \
+         fmt << "expr '" << #expr << " false (" << msg << ")";           \
+         _test.failure(BOTAN_CURRENT_FUNCTION, fmt.str());              \
+         }                                                              \
+      });                                                               \
+   } while(0)
+
+#define BOTAN_TEST_CASE(name, descr, block) size_t test_ ## name() {     \
+   Test_State _test;                                                    \
+   BOTAN_CONFIRM_NOTHROW(block);                                           \
+   test_report(descr, _test.ran(), _test.failed());                     \
+   return _test.failed();                                   \
+   }
+
+//#define TEST(expr, msg) do { if(!(expr)) { ++fails; std::cout << msg; } while(0)
 
 #define TEST_DATA_DIR     "src/tests/data"
 #define TEST_DATA_DIR_PK  "src/tests/data/pubkey"
@@ -75,6 +138,7 @@ size_t test_dh();
 size_t test_dlies();
 size_t test_elgamal();
 size_t test_ecc_pointmul();
+size_t test_ecc_random();
 size_t test_ecdsa();
 size_t test_gost_3410();
 size_t test_curve25519();
@@ -94,6 +158,7 @@ size_t test_pk_keygen();
 size_t test_bigint();
 
 size_t test_ecc_unit();
+size_t test_ecc_randomized();
 size_t test_ecdsa_unit();
 size_t test_ecdh_unit();