Add more tests for random prime and DL group generation

1 files changed, 85 insertions, 0 deletions

diff --git a/src/tests/test_bigint.cpp b/src/tests/test_bigint.cpp
index 096788f17..1d442a8bb 100644
--- a/src/tests/test_bigint.cpp
+++ b/src/tests/test_bigint.cpp
@@ -30,7 +30,9 @@ class BigInt_Unit_Tests : public Test
 
          results.push_back(test_bigint_sizes());
          results.push_back(test_random_integer());
+         results.push_back(test_random_prime());
          results.push_back(test_encode());
+         results.push_back(test_bigint_io());
 
          return results;
          }
@@ -80,6 +82,51 @@ class BigInt_Unit_Tests : public Test
          return result;
          }
 
+      Test::Result test_random_prime()
+         {
+         Test::Result result("BigInt prime generation");
+
+         result.test_throws("Invalid arg", []{ Botan::random_prime(Test::rng(), 0); });
+         result.test_throws("Invalid arg", []{ Botan::random_prime(Test::rng(), 1); });
+         result.test_throws("Invalid arg", []{ Botan::random_prime(Test::rng(), 2, 0); });
+         result.test_throws("Invalid arg", []{ Botan::random_prime(Test::rng(), 2, 1, 1, 3); });
+         result.test_throws("Invalid arg", []{ Botan::random_prime(Test::rng(), 2, 1, 0, 2); });
+
+         BigInt p = Botan::random_prime(Test::rng(), 2);
+         result.confirm("Only two 2-bit primes", p == 2 || p == 3);
+
+         p = Botan::random_prime(Test::rng(), 3);
+         result.confirm("Only two 3-bit primes", p == 5 || p == 7);
+
+         p = Botan::random_prime(Test::rng(), 4);
+         result.confirm("Only two 4-bit primes", p == 11 || p == 13);
+
+         for(size_t bits = 5; bits <= 32; ++bits)
+            {
+            p = Botan::random_prime(Test::rng(), bits);
+            result.test_eq("Expected bit size", p.bits(), bits);
+            result.test_eq("P is prime", Botan::is_prime(p, Test::rng()), true);
+            }
+
+         for(size_t bits = 5; bits <= 32; ++bits)
+            {
+            const BigInt last_p = p;
+            p = Botan::random_prime(Test::rng(), bits, last_p);
+
+            result.test_eq("Relatively prime", Botan::gcd(last_p, p), 1);
+            result.test_eq("Expected bit size", p.bits(), bits);
+            result.test_eq("P is prime", Botan::is_prime(p, Test::rng()), true);
+            }
+
+         const size_t safe_prime_bits = 65;
+         const BigInt safe_prime = Botan::random_safe_prime(Test::rng(), safe_prime_bits);
+         result.test_eq("Safe prime size", safe_prime.bits(), safe_prime_bits);
+         result.confirm("P is prime", Botan::is_prime(safe_prime, Test::rng()));
+         result.confirm("(P-1)/2 is prime", Botan::is_prime((safe_prime-1)/2, Test::rng()));
+
+         return result;
+         }
+
       Test::Result test_random_integer()
          {
          Test::Result result("BigInt::random_integer");
@@ -164,6 +211,44 @@ class BigInt_Unit_Tests : public Test
 
          return result;
          }
+
+      Test::Result test_bigint_io()
+         {
+         Test::Result result("BigInt IO operators");
+
+         const std::map<std::string, Botan::BigInt> str_to_val = {
+            { "-13", -Botan::BigInt(13) },
+            { "0", Botan::BigInt(0) },
+            { "0x13", Botan::BigInt(0x13) },
+            { "1", Botan::BigInt(1) },
+            { "4294967297", Botan::BigInt(2147483648)*2 + 1 }
+         };
+
+         for(auto vec : str_to_val)
+            {
+            Botan::BigInt n;
+            std::istringstream iss;
+
+            iss.str(vec.first);
+            iss >> n;
+            result.test_eq("input '" + vec.first + "'", n, vec.second);
+            }
+
+         BigInt n = 33;
+
+         std::ostringstream oss;
+         oss << n;
+         result.test_eq("output 33 dec", oss.str(), "33");
+
+         oss.str("");
+         oss << std::hex << n;
+         result.test_eq("output 33 hex", oss.str(), "21");
+
+         result.test_throws("octal output not supported",
+                            [&]{ oss << std::oct << n; });
+
+         return result;
+         }
    };
 
 BOTAN_REGISTER_TEST("bigint_unit", BigInt_Unit_Tests);