Merge #10321: Use FastRandomContext for all tests

e94584858 scripted-diff: Use new naming style for insecure_rand* functions (Pieter Wuille)
2fcd9cc86 scripted-diff: Use randbits/bool instead of randrange where possible (Pieter Wuille)
2ada67852 Use randbits instead of ad-hoc emulation in prevector tests (Pieter Wuille)
5f0b04eed Replace rand() & ((1 << N) - 1) with randbits(N) (Pieter Wuille)
3ecabae36 Replace more rand() % NUM by randranges (Pieter Wuille)
efee1db21 scripted-diff: use insecure_rand256/randrange more (Pieter Wuille)
1119927df Add various insecure_rand wrappers for tests (Pieter Wuille)
124d13a58 Merge test_random.h into test_bitcoin.h (Pieter Wuille)
90620d66c scripted-diff: Rename cuckoo tests' local rand context (Pieter Wuille)
37e864eb9 Add FastRandomContext::rand256() and ::randbytes() (Pieter Wuille)

Tree-SHA512: d09705a3ec718ae792f7d66a75401903ba7b9c9d3fc36669d6e3b9242f0194738106be26baefc8a8e3fa6df7c9a35978c71c0c430278a028b331df23a3ea3070

26 files changed, 202 insertions, 190 deletions

diff --git a/src/Makefile.test.include b/src/Makefile.test.include
index 950059ed86..13e0a03c76 100644
--- a/src/Makefile.test.include
+++ b/src/Makefile.test.include
@@ -74,7 +74,6 @@ BITCOIN_TESTS =\
   test/test_bitcoin.cpp \
   test/test_bitcoin.h \
   test/test_bitcoin_main.cpp \
-  test/test_random.h \
   test/testutil.cpp \
   test/testutil.h \
   test/timedata_tests.cpp \
diff --git a/src/random.cpp b/src/random.cpp
index de7553c825..e1ccfa5f24 100644
--- a/src/random.cpp
+++ b/src/random.cpp
@@ -304,6 +304,26 @@ void FastRandomContext::RandomSeed()
     requires_seed = false;
 }
 
+uint256 FastRandomContext::rand256()
+{
+    if (bytebuf_size < 32) {
+        FillByteBuffer();
+    }
+    uint256 ret;
+    memcpy(ret.begin(), bytebuf + 64 - bytebuf_size, 32);
+    bytebuf_size -= 32;
+    return ret;
+}
+
+std::vector<unsigned char> FastRandomContext::randbytes(size_t len)
+{
+    std::vector<unsigned char> ret(len);
+    if (len > 0) {
+        rng.Output(&ret[0], len);
+    }
+    return ret;
+}
+
 FastRandomContext::FastRandomContext(const uint256& seed) : requires_seed(false), bytebuf_size(0), bitbuf_size(0)
 {
     rng.SetKey(seed.begin(), 32);
diff --git a/src/random.h b/src/random.h
index 6a63d57429..dcb74eadb5 100644
--- a/src/random.h
+++ b/src/random.h
@@ -110,9 +110,15 @@ public:
         }
     }
 
+    /** Generate random bytes. */
+    std::vector<unsigned char> randbytes(size_t len);
+
     /** Generate a random 32-bit integer. */
     uint32_t rand32() { return randbits(32); }
 
+    /** generate a random uint256. */
+    uint256 rand256();
+
     /** Generate a random boolean. */
     bool randbool() { return randbits(1); }
 };
diff --git a/src/test/DoS_tests.cpp b/src/test/DoS_tests.cpp
index e6b45a3b5e..a7a3a1bdf0 100644
--- a/src/test/DoS_tests.cpp
+++ b/src/test/DoS_tests.cpp
@@ -129,7 +129,7 @@ BOOST_AUTO_TEST_CASE(DoS_bantime)
 CTransactionRef RandomOrphan()
 {
     std::map<uint256, COrphanTx>::iterator it;
-    it = mapOrphanTransactions.lower_bound(GetRandHash());
+    it = mapOrphanTransactions.lower_bound(InsecureRand256());
     if (it == mapOrphanTransactions.end())
         it = mapOrphanTransactions.begin();
     return it->second.tx;
@@ -148,7 +148,7 @@ BOOST_AUTO_TEST_CASE(DoS_mapOrphans)
         CMutableTransaction tx;
         tx.vin.resize(1);
         tx.vin[0].prevout.n = 0;
-        tx.vin[0].prevout.hash = GetRandHash();
+        tx.vin[0].prevout.hash = InsecureRand256();
         tx.vin[0].scriptSig << OP_1;
         tx.vout.resize(1);
         tx.vout[0].nValue = 1*CENT;
diff --git a/src/test/blockencodings_tests.cpp b/src/test/blockencodings_tests.cpp
index 9e4a56919d..10a40fea3c 100644
--- a/src/test/blockencodings_tests.cpp
+++ b/src/test/blockencodings_tests.cpp
@@ -30,16 +30,16 @@ static CBlock BuildBlockTestCase() {
     block.vtx.resize(3);
     block.vtx[0] = MakeTransactionRef(tx);
     block.nVersion = 42;
-    block.hashPrevBlock = GetRandHash();
+    block.hashPrevBlock = InsecureRand256();
     block.nBits = 0x207fffff;
 
-    tx.vin[0].prevout.hash = GetRandHash();
+    tx.vin[0].prevout.hash = InsecureRand256();
     tx.vin[0].prevout.n = 0;
     block.vtx[1] = MakeTransactionRef(tx);
 
     tx.vin.resize(10);
     for (size_t i = 0; i < tx.vin.size(); i++) {
-        tx.vin[i].prevout.hash = GetRandHash();
+        tx.vin[i].prevout.hash = InsecureRand256();
         tx.vin[i].prevout.n = 0;
     }
     block.vtx[2] = MakeTransactionRef(tx);
@@ -283,7 +283,7 @@ BOOST_AUTO_TEST_CASE(EmptyBlockRoundTripTest)
     block.vtx.resize(1);
     block.vtx[0] = MakeTransactionRef(std::move(coinbase));
     block.nVersion = 42;
-    block.hashPrevBlock = GetRandHash();
+    block.hashPrevBlock = InsecureRand256();
     block.nBits = 0x207fffff;
 
     bool mutated;
@@ -316,7 +316,7 @@ BOOST_AUTO_TEST_CASE(EmptyBlockRoundTripTest)
 
 BOOST_AUTO_TEST_CASE(TransactionsRequestSerializationTest) {
     BlockTransactionsRequest req1;
-    req1.blockhash = GetRandHash();
+    req1.blockhash = InsecureRand256();
     req1.indexes.resize(4);
     req1.indexes[0] = 0;
     req1.indexes[1] = 1;
diff --git a/src/test/bloom_tests.cpp b/src/test/bloom_tests.cpp
index 27bc92d670..1788ee1326 100644
--- a/src/test/bloom_tests.cpp
+++ b/src/test/bloom_tests.cpp
@@ -463,7 +463,7 @@ BOOST_AUTO_TEST_CASE(merkle_block_4_test_update_none)
 
 static std::vector<unsigned char> RandomData()
 {
-    uint256 r = GetRandHash();
+    uint256 r = InsecureRand256();
     return std::vector<unsigned char>(r.begin(), r.end());
 }
 
diff --git a/src/test/checkqueue_tests.cpp b/src/test/checkqueue_tests.cpp
index 287395c6c6..bf999eb524 100644
--- a/src/test/checkqueue_tests.cpp
+++ b/src/test/checkqueue_tests.cpp
@@ -160,7 +160,7 @@ void Correct_Queue_range(std::vector<size_t> range)
         FakeCheckCheckCompletion::n_calls = 0;
         CCheckQueueControl<FakeCheckCheckCompletion> control(small_queue.get());
         while (total) {
-            vChecks.resize(std::min(total, (size_t) GetRand(10)));
+            vChecks.resize(std::min(total, (size_t) InsecureRandRange(10)));
             total -= vChecks.size();
             control.Add(vChecks);
         }
@@ -204,7 +204,7 @@ BOOST_AUTO_TEST_CASE(test_CheckQueue_Correct_Random)
 {
     std::vector<size_t> range;
     range.reserve(100000/1000);
-    for (size_t i = 2; i < 100000; i += std::max((size_t)1, (size_t)GetRand(std::min((size_t)1000, ((size_t)100000) - i))))
+    for (size_t i = 2; i < 100000; i += std::max((size_t)1, (size_t)InsecureRandRange(std::min((size_t)1000, ((size_t)100000) - i))))
         range.push_back(i);
     Correct_Queue_range(range);
 }
@@ -224,7 +224,7 @@ BOOST_AUTO_TEST_CASE(test_CheckQueue_Catches_Failure)
         CCheckQueueControl<FailingCheck> control(fail_queue.get());
         size_t remaining = i;
         while (remaining) {
-            size_t r = GetRand(10);
+            size_t r = InsecureRandRange(10);
 
             std::vector<FailingCheck> vChecks;
             vChecks.reserve(r);
@@ -286,7 +286,7 @@ BOOST_AUTO_TEST_CASE(test_CheckQueue_UniqueCheck)
     {
         CCheckQueueControl<UniqueCheck> control(queue.get());
         while (total) {
-            size_t r = GetRand(10);
+            size_t r = InsecureRandRange(10);
             std::vector<UniqueCheck> vChecks;
             for (size_t k = 0; k < r && total; k++)
                 vChecks.emplace_back(--total);
@@ -320,7 +320,7 @@ BOOST_AUTO_TEST_CASE(test_CheckQueue_Memory)
         {
             CCheckQueueControl<MemoryCheck> control(queue.get());
             while (total) {
-                size_t r = GetRand(10);
+                size_t r = InsecureRandRange(10);
                 std::vector<MemoryCheck> vChecks;
                 for (size_t k = 0; k < r && total; k++) {
                     total--;
diff --git a/src/test/coins_tests.cpp b/src/test/coins_tests.cpp
index 0ed71b96fc..a72975d6e4 100644
--- a/src/test/coins_tests.cpp
+++ b/src/test/coins_tests.cpp
@@ -8,7 +8,6 @@
 #include "undo.h"
 #include "utilstrencodings.h"
 #include "test/test_bitcoin.h"
-#include "test/test_random.h"
 #include "validation.h"
 #include "consensus/validation.h"
 
@@ -44,7 +43,7 @@ public:
             return false;
         }
         coin = it->second;
-        if (coin.IsSpent() && insecure_rand() % 2 == 0) {
+        if (coin.IsSpent() && InsecureRandBool() == 0) {
             // Randomly return false in case of an empty entry.
             return false;
         }
@@ -65,7 +64,7 @@ public:
             if (it->second.flags & CCoinsCacheEntry::DIRTY) {
                 // Same optimization used in CCoinsViewDB is to only write dirty entries.
                 map_[it->first] = it->second.coin;
-                if (it->second.coin.IsSpent() && insecure_rand() % 3 == 0) {
+                if (it->second.coin.IsSpent() && InsecureRandRange(3) == 0) {
                     // Randomly delete empty entries on write.
                     map_.erase(it->first);
                 }
@@ -140,31 +139,31 @@ BOOST_AUTO_TEST_CASE(coins_cache_simulation_test)
     std::vector<uint256> txids;
     txids.resize(NUM_SIMULATION_ITERATIONS / 8);
     for (unsigned int i = 0; i < txids.size(); i++) {
-        txids[i] = GetRandHash();
+        txids[i] = InsecureRand256();
     }
 
     for (unsigned int i = 0; i < NUM_SIMULATION_ITERATIONS; i++) {
         // Do a random modification.
         {
-            uint256 txid = txids[insecure_rand() % txids.size()]; // txid we're going to modify in this iteration.
+            uint256 txid = txids[InsecureRandRange(txids.size())]; // txid we're going to modify in this iteration.
             Coin& coin = result[COutPoint(txid, 0)];
-            const Coin& entry = (insecure_rand() % 500 == 0) ? AccessByTxid(*stack.back(), txid) : stack.back()->AccessCoin(COutPoint(txid, 0));
+            const Coin& entry = (InsecureRandRange(500) == 0) ? AccessByTxid(*stack.back(), txid) : stack.back()->AccessCoin(COutPoint(txid, 0));
             BOOST_CHECK(coin == entry);
 
-            if (insecure_rand() % 5 == 0 || coin.IsSpent()) {
+            if (InsecureRandRange(5) == 0 || coin.IsSpent()) {
                 Coin newcoin;
-                newcoin.out.nValue = insecure_rand();
+                newcoin.out.nValue = InsecureRand32();
                 newcoin.nHeight = 1;
-                if (insecure_rand() % 16 == 0 && coin.IsSpent()) {
-                    newcoin.out.scriptPubKey.assign(1 + (insecure_rand() & 0x3F), OP_RETURN);
+                if (InsecureRandRange(16) == 0 && coin.IsSpent()) {
+                    newcoin.out.scriptPubKey.assign(1 + InsecureRandBits(6), OP_RETURN);
                     BOOST_CHECK(newcoin.out.scriptPubKey.IsUnspendable());
                     added_an_unspendable_entry = true;
                 } else {
-                    newcoin.out.scriptPubKey.assign(insecure_rand() & 0x3F, 0); // Random sizes so we can test memory usage accounting
+                    newcoin.out.scriptPubKey.assign(InsecureRandBits(6), 0); // Random sizes so we can test memory usage accounting
                     (coin.IsSpent() ? added_an_entry : updated_an_entry) = true;
                     coin = newcoin;
                 }
-                stack.back()->AddCoin(COutPoint(txid, 0), std::move(newcoin), !coin.IsSpent() || insecure_rand() & 1);
+                stack.back()->AddCoin(COutPoint(txid, 0), std::move(newcoin), !coin.IsSpent() || InsecureRand32() & 1);
             } else {
                 removed_an_entry = true;
                 coin.Clear();
@@ -173,15 +172,15 @@ BOOST_AUTO_TEST_CASE(coins_cache_simulation_test)
         }
 
         // One every 10 iterations, remove a random entry from the cache
-        if (insecure_rand() % 10 == 0) {
-            COutPoint out(txids[insecure_rand() % txids.size()], 0);
-            int cacheid = insecure_rand() % stack.size();
+        if (InsecureRandRange(10) == 0) {
+            COutPoint out(txids[InsecureRand32() % txids.size()], 0);
+            int cacheid = InsecureRand32() % stack.size();
             stack[cacheid]->Uncache(out);
             uncached_an_entry |= !stack[cacheid]->HaveCoinInCache(out);
         }
 
         // Once every 1000 iterations and at the end, verify the full cache.
-        if (insecure_rand() % 1000 == 1 || i == NUM_SIMULATION_ITERATIONS - 1) {
+        if (InsecureRandRange(1000) == 1 || i == NUM_SIMULATION_ITERATIONS - 1) {
             for (auto it = result.begin(); it != result.end(); it++) {
                 bool have = stack.back()->HaveCoin(it->first);
                 const Coin& coin = stack.back()->AccessCoin(it->first);
@@ -199,22 +198,22 @@ BOOST_AUTO_TEST_CASE(coins_cache_simulation_test)
             }
         }
 
-        if (insecure_rand() % 100 == 0) {
+        if (InsecureRandRange(100) == 0) {
             // Every 100 iterations, flush an intermediate cache
-            if (stack.size() > 1 && insecure_rand() % 2 == 0) {
-                unsigned int flushIndex = insecure_rand() % (stack.size() - 1);
+            if (stack.size() > 1 && InsecureRandBool() == 0) {
+                unsigned int flushIndex = InsecureRandRange(stack.size() - 1);
                 stack[flushIndex]->Flush();
             }
         }
-        if (insecure_rand() % 100 == 0) {
+        if (InsecureRandRange(100) == 0) {
             // Every 100 iterations, change the cache stack.
-            if (stack.size() > 0 && insecure_rand() % 2 == 0) {
+            if (stack.size() > 0 && InsecureRandBool() == 0) {
                 //Remove the top cache
                 stack.back()->Flush();
                 delete stack.back();
                 stack.pop_back();
             }
-            if (stack.size() == 0 || (stack.size() < 4 && insecure_rand() % 2)) {
+            if (stack.size() == 0 || (stack.size() < 4 && InsecureRandBool())) {
                 //Add a new cache
                 CCoinsView* tip = &base;
                 if (stack.size() > 0) {
@@ -254,7 +253,7 @@ UtxoData utxoData;
 
 UtxoData::iterator FindRandomFrom(const std::set<COutPoint> &utxoSet) {
     assert(utxoSet.size());
-    auto utxoSetIt = utxoSet.lower_bound(COutPoint(GetRandHash(), 0));
+    auto utxoSetIt = utxoSet.lower_bound(COutPoint(InsecureRand256(), 0));
     if (utxoSetIt == utxoSet.end()) {
         utxoSetIt = utxoSet.begin();
     }
@@ -287,7 +286,7 @@ BOOST_AUTO_TEST_CASE(updatecoins_simulation_test)
     std::set<COutPoint> utxoset;
 
     for (unsigned int i = 0; i < NUM_SIMULATION_ITERATIONS; i++) {
-        uint32_t randiter = insecure_rand();
+        uint32_t randiter = InsecureRand32();
 
         // 19/20 txs add a new transaction
         if (randiter % 20 < 19) {
@@ -295,14 +294,14 @@ BOOST_AUTO_TEST_CASE(updatecoins_simulation_test)
             tx.vin.resize(1);
             tx.vout.resize(1);
             tx.vout[0].nValue = i; //Keep txs unique unless intended to duplicate
-            tx.vout[0].scriptPubKey.assign(insecure_rand() & 0x3F, 0); // Random sizes so we can test memory usage accounting
-            unsigned int height = insecure_rand();
+            tx.vout[0].scriptPubKey.assign(InsecureRand32() & 0x3F, 0); // Random sizes so we can test memory usage accounting
+            unsigned int height = InsecureRand32();
             Coin old_coin;
 
             // 2/20 times create a new coinbase
             if (randiter % 20 < 2 || coinbase_coins.size() < 10) {
                 // 1/10 of those times create a duplicate coinbase
-                if (insecure_rand() % 10 == 0 && coinbase_coins.size()) {
+                if (InsecureRandRange(10) == 0 && coinbase_coins.size()) {
                     auto utxod = FindRandomFrom(coinbase_coins);
                     // Reuse the exact same coinbase
                     tx = std::get<0>(utxod->second);
@@ -412,7 +411,7 @@ BOOST_AUTO_TEST_CASE(updatecoins_simulation_test)
         }
 
         // Once every 1000 iterations and at the end, verify the full cache.
-        if (insecure_rand() % 1000 == 1 || i == NUM_SIMULATION_ITERATIONS - 1) {
+        if (InsecureRandRange(1000) == 1 || i == NUM_SIMULATION_ITERATIONS - 1) {
             for (auto it = result.begin(); it != result.end(); it++) {
                 bool have = stack.back()->HaveCoin(it->first);
                 const Coin& coin = stack.back()->AccessCoin(it->first);
@@ -422,31 +421,31 @@ BOOST_AUTO_TEST_CASE(updatecoins_simulation_test)
         }
 
         // One every 10 iterations, remove a random entry from the cache
-        if (utxoset.size() > 1 && insecure_rand() % 30 == 0) {
-            stack[insecure_rand() % stack.size()]->Uncache(FindRandomFrom(utxoset)->first);
+        if (utxoset.size() > 1 && InsecureRandRange(30) == 0) {
+            stack[InsecureRand32() % stack.size()]->Uncache(FindRandomFrom(utxoset)->first);
         }
-        if (disconnected_coins.size() > 1 && insecure_rand() % 30 == 0) {
-            stack[insecure_rand() % stack.size()]->Uncache(FindRandomFrom(disconnected_coins)->first);
+        if (disconnected_coins.size() > 1 && InsecureRandRange(30) == 0) {
+            stack[InsecureRand32() % stack.size()]->Uncache(FindRandomFrom(disconnected_coins)->first);
         }
-        if (duplicate_coins.size() > 1 && insecure_rand() % 30 == 0) {
-            stack[insecure_rand() % stack.size()]->Uncache(FindRandomFrom(duplicate_coins)->first);
+        if (duplicate_coins.size() > 1 && InsecureRandRange(30) == 0) {
+            stack[InsecureRand32() % stack.size()]->Uncache(FindRandomFrom(duplicate_coins)->first);
         }
 
-        if (insecure_rand() % 100 == 0) {
+        if (InsecureRandRange(100) == 0) {
             // Every 100 iterations, flush an intermediate cache
-            if (stack.size() > 1 && insecure_rand() % 2 == 0) {
-                unsigned int flushIndex = insecure_rand() % (stack.size() - 1);
+            if (stack.size() > 1 && InsecureRandBool() == 0) {
+                unsigned int flushIndex = InsecureRandRange(stack.size() - 1);
                 stack[flushIndex]->Flush();
             }
         }
-        if (insecure_rand() % 100 == 0) {
+        if (InsecureRandRange(100) == 0) {
             // Every 100 iterations, change the cache stack.
-            if (stack.size() > 0 && insecure_rand() % 2 == 0) {
+            if (stack.size() > 0 && InsecureRandBool() == 0) {
                 stack.back()->Flush();
                 delete stack.back();
                 stack.pop_back();
             }
-            if (stack.size() == 0 || (stack.size() < 4 && insecure_rand() % 2)) {
+            if (stack.size() == 0 || (stack.size() < 4 && InsecureRandBool())) {
                 CCoinsView* tip = &base;
                 if (stack.size() > 0) {
                     tip = stack.back();
diff --git a/src/test/crypto_tests.cpp b/src/test/crypto_tests.cpp
index 72e562808a..a4f0e17c99 100644
--- a/src/test/crypto_tests.cpp
+++ b/src/test/crypto_tests.cpp
@@ -13,7 +13,6 @@
 #include "random.h"
 #include "utilstrencodings.h"
 #include "test/test_bitcoin.h"
-#include "test/test_random.h"
 
 #include <vector>
 
@@ -39,7 +38,7 @@ void TestVector(const Hasher &h, const In &in, const Out &out) {
         Hasher hasher(h);
         size_t pos = 0;
         while (pos < in.size()) {
-            size_t len = insecure_rand() % ((in.size() - pos + 1) / 2 + 1);
+            size_t len = InsecureRandRange((in.size() - pos + 1) / 2 + 1);
             hasher.Write((unsigned char*)&in[pos], len);
             pos += len;
             if (pos > 0 && pos + 2 * out.size() > in.size() && pos < in.size()) {
diff --git a/src/test/cuckoocache_tests.cpp b/src/test/cuckoocache_tests.cpp
index 8cae4e66e8..ed391e184c 100644
--- a/src/test/cuckoocache_tests.cpp
+++ b/src/test/cuckoocache_tests.cpp
@@ -23,18 +23,18 @@
  *  using BOOST_CHECK_CLOSE to fail.
  *
  */
-FastRandomContext insecure_rand(true);
+FastRandomContext local_rand_ctx(true);
 
 BOOST_AUTO_TEST_SUITE(cuckoocache_tests);
 
 
-/** insecure_GetRandHash fills in a uint256 from insecure_rand
+/** insecure_GetRandHash fills in a uint256 from local_rand_ctx
  */
 void insecure_GetRandHash(uint256& t)
 {
     uint32_t* ptr = (uint32_t*)t.begin();
     for (uint8_t j = 0; j < 8; ++j)
-        *(ptr++) = insecure_rand.rand32();
+        *(ptr++) = local_rand_ctx.rand32();
 }
 
 
@@ -45,7 +45,7 @@ void insecure_GetRandHash(uint256& t)
  */
 BOOST_AUTO_TEST_CASE(test_cuckoocache_no_fakes)
 {
-    insecure_rand = FastRandomContext(true);
+    local_rand_ctx = FastRandomContext(true);
     CuckooCache::cache<uint256, SignatureCacheHasher> cc{};
     size_t megabytes = 4;
     cc.setup_bytes(megabytes << 20);
@@ -66,7 +66,7 @@ BOOST_AUTO_TEST_CASE(test_cuckoocache_no_fakes)
 template <typename Cache>
 double test_cache(size_t megabytes, double load)
 {
-    insecure_rand = FastRandomContext(true);
+    local_rand_ctx = FastRandomContext(true);
     std::vector<uint256> hashes;
     Cache set{};
     size_t bytes = megabytes * (1 << 20);
@@ -76,7 +76,7 @@ double test_cache(size_t megabytes, double load)
     for (uint32_t i = 0; i < n_insert; ++i) {
         uint32_t* ptr = (uint32_t*)hashes[i].begin();
         for (uint8_t j = 0; j < 8; ++j)
-            *(ptr++) = insecure_rand.rand32();
+            *(ptr++) = local_rand_ctx.rand32();
     }
     /** We make a copy of the hashes because future optimizations of the
      * cuckoocache may overwrite the inserted element, so the test is
@@ -137,7 +137,7 @@ template <typename Cache>
 void test_cache_erase(size_t megabytes)
 {
     double load = 1;
-    insecure_rand = FastRandomContext(true);
+    local_rand_ctx = FastRandomContext(true);
     std::vector<uint256> hashes;
     Cache set{};
     size_t bytes = megabytes * (1 << 20);
@@ -147,7 +147,7 @@ void test_cache_erase(size_t megabytes)
     for (uint32_t i = 0; i < n_insert; ++i) {
         uint32_t* ptr = (uint32_t*)hashes[i].begin();
         for (uint8_t j = 0; j < 8; ++j)
-            *(ptr++) = insecure_rand.rand32();
+            *(ptr++) = local_rand_ctx.rand32();
     }
     /** We make a copy of the hashes because future optimizations of the
      * cuckoocache may overwrite the inserted element, so the test is
@@ -200,7 +200,7 @@ template <typename Cache>
 void test_cache_erase_parallel(size_t megabytes)
 {
     double load = 1;
-    insecure_rand = FastRandomContext(true);
+    local_rand_ctx = FastRandomContext(true);
     std::vector<uint256> hashes;
     Cache set{};
     size_t bytes = megabytes * (1 << 20);
@@ -210,7 +210,7 @@ void test_cache_erase_parallel(size_t megabytes)
     for (uint32_t i = 0; i < n_insert; ++i) {
         uint32_t* ptr = (uint32_t*)hashes[i].begin();
         for (uint8_t j = 0; j < 8; ++j)
-            *(ptr++) = insecure_rand.rand32();
+            *(ptr++) = local_rand_ctx.rand32();
     }
     /** We make a copy of the hashes because future optimizations of the
      * cuckoocache may overwrite the inserted element, so the test is
@@ -302,7 +302,7 @@ void test_cache_generations()
     // iterations with non-deterministic values, so it isn't "overfit" to the
     // specific entropy in FastRandomContext(true) and implementation of the
     // cache.
-    insecure_rand = FastRandomContext(true);
+    local_rand_ctx = FastRandomContext(true);
 
     // block_activity models a chunk of network activity. n_insert elements are
     // adde to the cache. The first and last n/4 are stored for removal later
@@ -319,7 +319,7 @@ void test_cache_generations()
             for (uint32_t i = 0; i < n_insert; ++i) {
                 uint32_t* ptr = (uint32_t*)inserts[i].begin();
                 for (uint8_t j = 0; j < 8; ++j)
-                    *(ptr++) = insecure_rand.rand32();
+                    *(ptr++) = local_rand_ctx.rand32();
             }
             for (uint32_t i = 0; i < n_insert / 4; ++i)
                 reads.push_back(inserts[i]);
diff --git a/src/test/dbwrapper_tests.cpp b/src/test/dbwrapper_tests.cpp
index c9d9849ada..2d8a419bdb 100644
--- a/src/test/dbwrapper_tests.cpp
+++ b/src/test/dbwrapper_tests.cpp
@@ -31,7 +31,7 @@ BOOST_AUTO_TEST_CASE(dbwrapper)
         fs::path ph = fs::temp_directory_path() / fs::unique_path();
         CDBWrapper dbw(ph, (1 << 20), true, false, obfuscate);
         char key = 'k';
-        uint256 in = GetRandHash();
+        uint256 in = InsecureRand256();
         uint256 res;
 
         // Ensure that we're doing real obfuscation when obfuscate=true
@@ -53,11 +53,11 @@ BOOST_AUTO_TEST_CASE(dbwrapper_batch)
         CDBWrapper dbw(ph, (1 << 20), true, false, obfuscate);
 
         char key = 'i';
-        uint256 in = GetRandHash();
+        uint256 in = InsecureRand256();
         char key2 = 'j';
-        uint256 in2 = GetRandHash();
+        uint256 in2 = InsecureRand256();
         char key3 = 'k';
-        uint256 in3 = GetRandHash();
+        uint256 in3 = InsecureRand256();
 
         uint256 res;
         CDBBatch batch(dbw);
@@ -91,10 +91,10 @@ BOOST_AUTO_TEST_CASE(dbwrapper_iterator)
 
         // The two keys are intentionally chosen for ordering
         char key = 'j';
-        uint256 in = GetRandHash();
+        uint256 in = InsecureRand256();
         BOOST_CHECK(dbw.Write(key, in));
         char key2 = 'k';
-        uint256 in2 = GetRandHash();
+        uint256 in2 = InsecureRand256();
         BOOST_CHECK(dbw.Write(key2, in2));
 
         std::unique_ptr<CDBIterator> it(const_cast<CDBWrapper*>(&dbw)->NewIterator());
@@ -132,7 +132,7 @@ BOOST_AUTO_TEST_CASE(existing_data_no_obfuscate)
     // Set up a non-obfuscated wrapper to write some initial data.
     CDBWrapper* dbw = new CDBWrapper(ph, (1 << 10), false, false, false);
     char key = 'k';
-    uint256 in = GetRandHash();
+    uint256 in = InsecureRand256();
     uint256 res;
 
     BOOST_CHECK(dbw->Write(key, in));
@@ -155,7 +155,7 @@ BOOST_AUTO_TEST_CASE(existing_data_no_obfuscate)
     BOOST_CHECK(!odbw.IsEmpty()); // There should be existing data
     BOOST_CHECK(is_null_key(dbwrapper_private::GetObfuscateKey(odbw))); // The key should be an empty string
 
-    uint256 in2 = GetRandHash();
+    uint256 in2 = InsecureRand256();
     uint256 res3;
  
     // Check that we can write successfully
@@ -174,7 +174,7 @@ BOOST_AUTO_TEST_CASE(existing_data_reindex)
     // Set up a non-obfuscated wrapper to write some initial data.
     CDBWrapper* dbw = new CDBWrapper(ph, (1 << 10), false, false, false);
     char key = 'k';
-    uint256 in = GetRandHash();
+    uint256 in = InsecureRand256();
     uint256 res;
 
     BOOST_CHECK(dbw->Write(key, in));
@@ -193,7 +193,7 @@ BOOST_AUTO_TEST_CASE(existing_data_reindex)
     BOOST_CHECK(!odbw.Read(key, res2));
     BOOST_CHECK(!is_null_key(dbwrapper_private::GetObfuscateKey(odbw)));
 
-    uint256 in2 = GetRandHash();
+    uint256 in2 = InsecureRand256();
     uint256 res3;
  
     // Check that we can write successfully
diff --git a/src/test/hash_tests.cpp b/src/test/hash_tests.cpp
index bb7e473248..05b6b3b1e6 100644
--- a/src/test/hash_tests.cpp
+++ b/src/test/hash_tests.cpp
@@ -134,7 +134,7 @@ BOOST_AUTO_TEST_CASE(siphash)
     for (int i = 0; i < 16; ++i) {
         uint64_t k1 = ctx.rand64();
         uint64_t k2 = ctx.rand64();
-        uint256 x = GetRandHash();
+        uint256 x = InsecureRand256();
         uint32_t n = ctx.rand32();
         uint8_t nb[4];
         WriteLE32(nb, n);
diff --git a/src/test/merkle_tests.cpp b/src/test/merkle_tests.cpp
index f2f06fa8e2..1a1cf4399c 100644
--- a/src/test/merkle_tests.cpp
+++ b/src/test/merkle_tests.cpp
@@ -4,7 +4,6 @@
 
 #include "consensus/merkle.h"
 #include "test/test_bitcoin.h"
-#include "test/test_random.h"
 
 #include <boost/test/unit_test.hpp>
 
@@ -68,7 +67,7 @@ BOOST_AUTO_TEST_CASE(merkle_test)
 {
     for (int i = 0; i < 32; i++) {
         // Try 32 block sizes: all sizes from 0 to 16 inclusive, and then 15 random sizes.
-        int ntx = (i <= 16) ? i : 17 + (insecure_rand() % 4000);
+        int ntx = (i <= 16) ? i : 17 + (InsecureRandRange(4000));
         // Try up to 3 mutations.
         for (int mutate = 0; mutate <= 3; mutate++) {
             int duplicate1 = mutate >= 1 ? 1 << ctz(ntx) : 0; // The last how many transactions to duplicate first.
@@ -121,7 +120,7 @@ BOOST_AUTO_TEST_CASE(merkle_test)
                     // If ntx <= 16, try all branches. Otherwise, try 16 random ones.
                     int mtx = loop;
                     if (ntx > 16) {
-                        mtx = insecure_rand() % ntx;
+                        mtx = InsecureRandRange(ntx);
                     }
                     std::vector<uint256> newBranch = BlockMerkleBranch(block, mtx);
                     std::vector<uint256> oldBranch = BlockGetMerkleBranch(block, merkleTree, mtx);
diff --git a/src/test/miner_tests.cpp b/src/test/miner_tests.cpp
index a40060e657..c95800a728 100644
--- a/src/test/miner_tests.cpp
+++ b/src/test/miner_tests.cpp
@@ -372,7 +372,7 @@ BOOST_AUTO_TEST_CASE(CreateNewBlock_validity)
     while (chainActive.Tip()->nHeight < 209999) {
         CBlockIndex* prev = chainActive.Tip();
         CBlockIndex* next = new CBlockIndex();
-        next->phashBlock = new uint256(GetRandHash());
+        next->phashBlock = new uint256(InsecureRand256());
         pcoinsTip->SetBestBlock(next->GetBlockHash());
         next->pprev = prev;
         next->nHeight = prev->nHeight + 1;
@@ -384,7 +384,7 @@ BOOST_AUTO_TEST_CASE(CreateNewBlock_validity)
     while (chainActive.Tip()->nHeight < 210000) {
         CBlockIndex* prev = chainActive.Tip();
         CBlockIndex* next = new CBlockIndex();
-        next->phashBlock = new uint256(GetRandHash());
+        next->phashBlock = new uint256(InsecureRand256());
         pcoinsTip->SetBestBlock(next->GetBlockHash());
         next->pprev = prev;
         next->nHeight = prev->nHeight + 1;
diff --git a/src/test/pmt_tests.cpp b/src/test/pmt_tests.cpp
index a1cb32019a..708a9ca508 100644
--- a/src/test/pmt_tests.cpp
+++ b/src/test/pmt_tests.cpp
@@ -10,7 +10,6 @@
 #include "arith_uint256.h"
 #include "version.h"
 #include "test/test_bitcoin.h"
-#include "test/test_random.h"
 
 #include <vector>
 
@@ -22,8 +21,8 @@ class CPartialMerkleTreeTester : public CPartialMerkleTree
 public:
     // flip one bit in one of the hashes - this should break the authentication
     void Damage() {
-        unsigned int n = insecure_rand() % vHash.size();
-        int bit = insecure_rand() % 256;
+        unsigned int n = InsecureRandRange(vHash.size());
+        int bit = InsecureRandBits(8);
         *(vHash[n].begin() + (bit>>3)) ^= 1<<(bit&7);
     }
 };
@@ -32,7 +31,7 @@ BOOST_FIXTURE_TEST_SUITE(pmt_tests, BasicTestingSetup)
 
 BOOST_AUTO_TEST_CASE(pmt_test1)
 {
-    seed_insecure_rand(false);
+    SeedInsecureRand(false);
     static const unsigned int nTxCounts[] = {1, 4, 7, 17, 56, 100, 127, 256, 312, 513, 1000, 4095};
 
     for (int i = 0; i < 12; i++) {
@@ -63,7 +62,7 @@ BOOST_AUTO_TEST_CASE(pmt_test1)
             std::vector<bool> vMatch(nTx, false);
             std::vector<uint256> vMatchTxid1;
             for (unsigned int j=0; j<nTx; j++) {
-                bool fInclude = (insecure_rand() & ((1 << (att/2)) - 1)) == 0;
+                bool fInclude = InsecureRandBits(att / 2) == 0;
                 vMatch[j] = fInclude;
                 if (fInclude)
                     vMatchTxid1.push_back(vTxid[j]);
diff --git a/src/test/pow_tests.cpp b/src/test/pow_tests.cpp
index 3b79f8000d..b9fabd02e4 100644
--- a/src/test/pow_tests.cpp
+++ b/src/test/pow_tests.cpp
@@ -74,9 +74,9 @@ BOOST_AUTO_TEST_CASE(GetBlockProofEquivalentTime_test)
     }
 
     for (int j = 0; j < 1000; j++) {
-        CBlockIndex *p1 = &blocks[GetRand(10000)];
-        CBlockIndex *p2 = &blocks[GetRand(10000)];
-        CBlockIndex *p3 = &blocks[GetRand(10000)];
+        CBlockIndex *p1 = &blocks[InsecureRandRange(10000)];
+        CBlockIndex *p2 = &blocks[InsecureRandRange(10000)];
+        CBlockIndex *p3 = &blocks[InsecureRandRange(10000)];
 
         int64_t tdiff = GetBlockProofEquivalentTime(*p1, *p2, *p3, chainParams->GetConsensus());
         BOOST_CHECK_EQUAL(tdiff, p1->GetBlockTime() - p2->GetBlockTime());
diff --git a/src/test/prevector_tests.cpp b/src/test/prevector_tests.cpp
index cfed5e347e..354fed1c1d 100644
--- a/src/test/prevector_tests.cpp
+++ b/src/test/prevector_tests.cpp
@@ -9,7 +9,6 @@
 #include "streams.h"
 
 #include "test/test_bitcoin.h"
-#include "test/test_random.h"
 
 #include <boost/test/unit_test.hpp>
 
@@ -188,7 +187,7 @@ public:
     }
 
     prevector_tester() {
-        seed_insecure_rand();
+        SeedInsecureRand();
         rand_seed = insecure_rand_seed;
         rand_cache = insecure_rand_ctx;
     }
@@ -199,67 +198,65 @@ BOOST_AUTO_TEST_CASE(PrevectorTestInt)
     for (int j = 0; j < 64; j++) {
         prevector_tester<8, int> test;
         for (int i = 0; i < 2048; i++) {
-            int r = insecure_rand();
-            if ((r % 4) == 0) {
-                test.insert(insecure_rand() % (test.size() + 1), insecure_rand());
+            if (InsecureRandBits(2) == 0) {
+                test.insert(InsecureRandRange(test.size() + 1), InsecureRand32());
             }
-            if (test.size() > 0 && ((r >> 2) % 4) == 1) {
-                test.erase(insecure_rand() % test.size());
+            if (test.size() > 0 && InsecureRandBits(2) == 1) {
+                test.erase(InsecureRandRange(test.size()));
             }
-            if (((r >> 4) % 8) == 2) {
-                int new_size = std::max<int>(0, std::min<int>(30, test.size() + (insecure_rand() % 5) - 2));
+            if (InsecureRandBits(3) == 2) {
+                int new_size = std::max<int>(0, std::min<int>(30, test.size() + (InsecureRandRange(5)) - 2));
                 test.resize(new_size);
             }
-            if (((r >> 7) % 8) == 3) {
-                test.insert(insecure_rand() % (test.size() + 1), 1 + (insecure_rand() % 2), insecure_rand());
+            if (InsecureRandBits(3) == 3) {
+                test.insert(InsecureRandRange(test.size() + 1), 1 + InsecureRandBool(), InsecureRand32());
             }
-            if (((r >> 10) % 8) == 4) {
-                int del = std::min<int>(test.size(), 1 + (insecure_rand() % 2));
-                int beg = insecure_rand() % (test.size() + 1 - del);
+            if (InsecureRandBits(3) == 4) {
+                int del = std::min<int>(test.size(), 1 + (InsecureRandBool()));
+                int beg = InsecureRandRange(test.size() + 1 - del);
                 test.erase(beg, beg + del);
             }
-            if (((r >> 13) % 16) == 5) {
-                test.push_back(insecure_rand());
+            if (InsecureRandBits(4) == 5) {
+                test.push_back(InsecureRand32());
             }
-            if (test.size() > 0 && ((r >> 17) % 16) == 6) {
+            if (test.size() > 0 && InsecureRandBits(4) == 6) {
                 test.pop_back();
             }
-            if (((r >> 21) % 32) == 7) {
+            if (InsecureRandBits(5) == 7) {
                 int values[4];
-                int num = 1 + (insecure_rand() % 4);
+                int num = 1 + (InsecureRandBits(2));
                 for (int k = 0; k < num; k++) {
-                    values[k] = insecure_rand();
+                    values[k] = InsecureRand32();
                 }
-                test.insert_range(insecure_rand() % (test.size() + 1), values, values + num);
+                test.insert_range(InsecureRandRange(test.size() + 1), values, values + num);
             }
-            if (((r >> 26) % 32) == 8) {
-                int del = std::min<int>(test.size(), 1 + (insecure_rand() % 4));
-                int beg = insecure_rand() % (test.size() + 1 - del);
+            if (InsecureRandBits(5) == 8) {
+                int del = std::min<int>(test.size(), 1 + (InsecureRandBits(2)));
+                int beg = InsecureRandRange(test.size() + 1 - del);
                 test.erase(beg, beg + del);
             }
-            r = insecure_rand();
-            if (r % 32 == 9) {
-                test.reserve(insecure_rand() % 32);
+            if (InsecureRandBits(5) == 9) {
+                test.reserve(InsecureRandBits(5));
             }
-            if ((r >> 5) % 64 == 10) {
+            if (InsecureRandBits(6) == 10) {
                 test.shrink_to_fit();
             }
             if (test.size() > 0) {
-                test.update(insecure_rand() % test.size(), insecure_rand());
+                test.update(InsecureRandRange(test.size()), InsecureRand32());
             }
-            if (((r >> 11) % 1024) == 11) {
+            if (InsecureRandBits(10) == 11) {
                 test.clear();
             }
-            if (((r >> 21) % 512) == 12) {
-                test.assign(insecure_rand() % 32, insecure_rand());
+            if (InsecureRandBits(9) == 12) {
+                test.assign(InsecureRandBits(5), InsecureRand32());
             }
-            if (((r >> 15) % 8) == 3) {
+            if (InsecureRandBits(3) == 3) {
                 test.swap();
             }
-            if (((r >> 15) % 16) == 8) {
+            if (InsecureRandBits(4) == 8) {
                 test.copy();
             }
-            if (((r >> 15) % 32) == 18) {
+            if (InsecureRandBits(5) == 18) {
                 test.move();
             }
         }
diff --git a/src/test/random_tests.cpp b/src/test/random_tests.cpp
index 8596734226..132e190051 100644
--- a/src/test/random_tests.cpp
+++ b/src/test/random_tests.cpp
@@ -25,14 +25,21 @@ BOOST_AUTO_TEST_CASE(fastrandom_tests)
     BOOST_CHECK_EQUAL(ctx1.rand32(), ctx2.rand32());
     BOOST_CHECK_EQUAL(ctx1.rand64(), ctx2.rand64());
     BOOST_CHECK_EQUAL(ctx1.randbits(3), ctx2.randbits(3));
+    BOOST_CHECK(ctx1.randbytes(17) == ctx2.randbytes(17));
+    BOOST_CHECK(ctx1.rand256() == ctx2.rand256());
     BOOST_CHECK_EQUAL(ctx1.randbits(7), ctx2.randbits(7));
+    BOOST_CHECK(ctx1.randbytes(128) == ctx2.randbytes(128));
     BOOST_CHECK_EQUAL(ctx1.rand32(), ctx2.rand32());
     BOOST_CHECK_EQUAL(ctx1.randbits(3), ctx2.randbits(3));
+    BOOST_CHECK(ctx1.rand256() == ctx2.rand256());
+    BOOST_CHECK(ctx1.randbytes(50) == ctx2.randbytes(50));
 
     // Check that a nondeterministic ones are not
     FastRandomContext ctx3;
     FastRandomContext ctx4;
     BOOST_CHECK(ctx3.rand64() != ctx4.rand64()); // extremely unlikely to be equal
+    BOOST_CHECK(ctx3.rand256() != ctx4.rand256());
+    BOOST_CHECK(ctx3.randbytes(7) != ctx4.randbytes(7));
 }
 
 BOOST_AUTO_TEST_CASE(fastrandom_randbits)
diff --git a/src/test/sighash_tests.cpp b/src/test/sighash_tests.cpp
index 2f7c22084e..d882ca7a63 100644
--- a/src/test/sighash_tests.cpp
+++ b/src/test/sighash_tests.cpp
@@ -11,7 +11,6 @@
 #include "serialize.h"
 #include "streams.h"
 #include "test/test_bitcoin.h"
-#include "test/test_random.h"
 #include "util.h"
 #include "utilstrencodings.h"
 #include "version.h"
@@ -90,30 +89,30 @@ uint256 static SignatureHashOld(CScript scriptCode, const CTransaction& txTo, un
 void static RandomScript(CScript &script) {
     static const opcodetype oplist[] = {OP_FALSE, OP_1, OP_2, OP_3, OP_CHECKSIG, OP_IF, OP_VERIF, OP_RETURN, OP_CODESEPARATOR};
     script = CScript();
-    int ops = (insecure_rand() % 10);
+    int ops = (InsecureRandRange(10));
     for (int i=0; i<ops; i++)
-        script << oplist[insecure_rand() % (sizeof(oplist)/sizeof(oplist[0]))];
+        script << oplist[InsecureRandRange(sizeof(oplist)/sizeof(oplist[0]))];
 }
 
 void static RandomTransaction(CMutableTransaction &tx, bool fSingle) {
-    tx.nVersion = insecure_rand();
+    tx.nVersion = InsecureRand32();
     tx.vin.clear();
     tx.vout.clear();
-    tx.nLockTime = (insecure_rand() % 2) ? insecure_rand() : 0;
-    int ins = (insecure_rand() % 4) + 1;
-    int outs = fSingle ? ins : (insecure_rand() % 4) + 1;
+    tx.nLockTime = (InsecureRandBool()) ? InsecureRand32() : 0;
+    int ins = (InsecureRandBits(2)) + 1;
+    int outs = fSingle ? ins : (InsecureRandBits(2)) + 1;
     for (int in = 0; in < ins; in++) {
         tx.vin.push_back(CTxIn());
         CTxIn &txin = tx.vin.back();
-        txin.prevout.hash = GetRandHash();
-        txin.prevout.n = insecure_rand() % 4;
+        txin.prevout.hash = InsecureRand256();
+        txin.prevout.n = InsecureRandBits(2);
         RandomScript(txin.scriptSig);
-        txin.nSequence = (insecure_rand() % 2) ? insecure_rand() : (unsigned int)-1;
+        txin.nSequence = (InsecureRandBool()) ? InsecureRand32() : (unsigned int)-1;
     }
     for (int out = 0; out < outs; out++) {
         tx.vout.push_back(CTxOut());
         CTxOut &txout = tx.vout.back();
-        txout.nValue = insecure_rand() % 100000000;
+        txout.nValue = InsecureRandRange(100000000);
         RandomScript(txout.scriptPubKey);
     }
 }
@@ -122,7 +121,7 @@ BOOST_FIXTURE_TEST_SUITE(sighash_tests, BasicTestingSetup)
 
 BOOST_AUTO_TEST_CASE(sighash_test)
 {
-    seed_insecure_rand(false);
+    SeedInsecureRand(false);
 
     #if defined(PRINT_SIGHASH_JSON)
     std::cout << "[\n";
@@ -134,12 +133,12 @@ BOOST_AUTO_TEST_CASE(sighash_test)
     nRandomTests = 500;
     #endif
     for (int i=0; i<nRandomTests; i++) {
-        int nHashType = insecure_rand();
+        int nHashType = InsecureRand32();
         CMutableTransaction txTo;
         RandomTransaction(txTo, (nHashType & 0x1f) == SIGHASH_SINGLE);
         CScript scriptCode;
         RandomScript(scriptCode);
-        int nIn = insecure_rand() % txTo.vin.size();
+        int nIn = InsecureRandRange(txTo.vin.size());
 
         uint256 sh, sho;
         sho = SignatureHashOld(scriptCode, txTo, nIn, nHashType);
diff --git a/src/test/skiplist_tests.cpp b/src/test/skiplist_tests.cpp
index 900b4908f0..77c321cdf6 100644
--- a/src/test/skiplist_tests.cpp
+++ b/src/test/skiplist_tests.cpp
@@ -5,7 +5,6 @@
 #include "chain.h"
 #include "util.h"
 #include "test/test_bitcoin.h"
-#include "test/test_random.h"
 
 #include <vector>
 
@@ -35,8 +34,8 @@ BOOST_AUTO_TEST_CASE(skiplist_test)
     }
 
     for (int i=0; i < 1000; i++) {
-        int from = insecure_rand() % (SKIPLIST_LENGTH - 1);
-        int to = insecure_rand() % (from + 1);
+        int from = InsecureRandRange(SKIPLIST_LENGTH - 1);
+        int to = InsecureRandRange(from + 1);
 
         BOOST_CHECK(vIndex[SKIPLIST_LENGTH - 1].GetAncestor(from) == &vIndex[from]);
         BOOST_CHECK(vIndex[from].GetAncestor(to) == &vIndex[to]);
@@ -78,7 +77,7 @@ BOOST_AUTO_TEST_CASE(getlocator_test)
 
     // Test 100 random starting points for locators.
     for (int n=0; n<100; n++) {
-        int r = insecure_rand() % 150000;
+        int r = InsecureRandRange(150000);
         CBlockIndex* tip = (r < 100000) ? &vBlocksMain[r] : &vBlocksSide[r - 100000];
         CBlockLocator locator = chain.GetLocator(tip);
 
@@ -116,7 +115,7 @@ BOOST_AUTO_TEST_CASE(findearliestatleast_test)
         } else {
             // randomly choose something in the range [MTP, MTP*2]
             int64_t medianTimePast = vBlocksMain[i].GetMedianTimePast();
-            int r = insecure_rand() % medianTimePast;
+            int r = InsecureRandRange(medianTimePast);
             vBlocksMain[i].nTime = r + medianTimePast;
             vBlocksMain[i].nTimeMax = std::max(vBlocksMain[i].nTime, vBlocksMain[i-1].nTimeMax);
         }
@@ -135,7 +134,7 @@ BOOST_AUTO_TEST_CASE(findearliestatleast_test)
     // Verify that FindEarliestAtLeast is correct.
     for (unsigned int i=0; i<10000; ++i) {
         // Pick a random element in vBlocksMain.
-        int r = insecure_rand() % vBlocksMain.size();
+        int r = InsecureRandRange(vBlocksMain.size());
         int64_t test_time = vBlocksMain[r].nTime;
         CBlockIndex *ret = chain.FindEarliestAtLeast(test_time);
         BOOST_CHECK(ret->nTimeMax >= test_time);
diff --git a/src/test/test_bitcoin.cpp b/src/test/test_bitcoin.cpp
index cb625bda11..c1aea1680a 100644
--- a/src/test/test_bitcoin.cpp
+++ b/src/test/test_bitcoin.cpp
@@ -59,7 +59,7 @@ TestingSetup::TestingSetup(const std::string& chainName) : BasicTestingSetup(cha
 
         RegisterAllCoreRPCCommands(tableRPC);
         ClearDatadirCache();
-        pathTemp = GetTempPath() / strprintf("test_bitcoin_%lu_%i", (unsigned long)GetTime(), (int)(GetRand(100000)));
+        pathTemp = GetTempPath() / strprintf("test_bitcoin_%lu_%i", (unsigned long)GetTime(), (int)(InsecureRandRange(100000)));
         fs::create_directories(pathTemp);
         ForceSetArg("-datadir", pathTemp.string());
         mempool.setSanityCheck(1.0);
diff --git a/src/test/test_bitcoin.h b/src/test/test_bitcoin.h
index 60a86d8c48..0087eeb2d7 100644
--- a/src/test/test_bitcoin.h
+++ b/src/test/test_bitcoin.h
@@ -9,11 +9,32 @@
 #include "fs.h"
 #include "key.h"
 #include "pubkey.h"
+#include "random.h"
 #include "txdb.h"
 #include "txmempool.h"
 
 #include <boost/thread.hpp>
 
+extern uint256 insecure_rand_seed;
+extern FastRandomContext insecure_rand_ctx;
+
+static inline void SeedInsecureRand(bool fDeterministic = false)
+{
+    if (fDeterministic) {
+        insecure_rand_seed = uint256();
+    } else {
+        insecure_rand_seed = GetRandHash();
+    }
+    insecure_rand_ctx = FastRandomContext(insecure_rand_seed);
+}
+
+static inline uint32_t InsecureRand32() { return insecure_rand_ctx.rand32(); }
+static inline uint256 InsecureRand256() { return insecure_rand_ctx.rand256(); }
+static inline uint64_t InsecureRandBits(int bits) { return insecure_rand_ctx.randbits(bits); }
+static inline uint64_t InsecureRandRange(uint64_t range) { return insecure_rand_ctx.randrange(range); }
+static inline bool InsecureRandBool() { return insecure_rand_ctx.randbool(); }
+static inline std::vector<unsigned char> InsecureRandBytes(size_t len) { return insecure_rand_ctx.randbytes(len); }
+
 /** Basic testing setup.
  * This just configures logging and chain parameters.
  */
diff --git a/src/test/test_random.h b/src/test/test_random.h
deleted file mode 100644
index 318c44df4d..0000000000
--- a/src/test/test_random.h
+++ /dev/null
@@ -1,29 +0,0 @@
-// Copyright (c) 2009-2010 Satoshi Nakamoto
-// Copyright (c) 2009-2016 The Bitcoin Core developers
-// Distributed under the MIT software license, see the accompanying
-// file COPYING or http://www.opensource.org/licenses/mit-license.php.
-
-#ifndef BITCOIN_TEST_RANDOM_H
-#define BITCOIN_TEST_RANDOM_H
-
-#include "random.h"
-
-extern uint256 insecure_rand_seed;
-extern FastRandomContext insecure_rand_ctx;
-
-static inline void seed_insecure_rand(bool fDeterministic = false)
-{
-    if (fDeterministic) {
-        insecure_rand_seed = uint256();
-    } else {
-        insecure_rand_seed = GetRandHash();
-    }
-    insecure_rand_ctx = FastRandomContext(insecure_rand_seed);
-}
-
-static inline uint32_t insecure_rand(void)
-{
-    return insecure_rand_ctx.rand32();
-}
-
-#endif
diff --git a/src/test/util_tests.cpp b/src/test/util_tests.cpp
index 10330c0c23..5e9dfb730b 100644
--- a/src/test/util_tests.cpp
+++ b/src/test/util_tests.cpp
@@ -10,7 +10,6 @@
 #include "utilstrencodings.h"
 #include "utilmoneystr.h"
 #include "test/test_bitcoin.h"
-#include "test/test_random.h"
 
 #include <stdint.h>
 #include <vector>
@@ -256,7 +255,7 @@ BOOST_AUTO_TEST_CASE(util_IsHex)
 
 BOOST_AUTO_TEST_CASE(util_seed_insecure_rand)
 {
-    seed_insecure_rand(true);
+    SeedInsecureRand(true);
     for (int mod=2;mod<11;mod++)
     {
         int mask = 1;
@@ -270,7 +269,7 @@ BOOST_AUTO_TEST_CASE(util_seed_insecure_rand)
         for (int i = 0; i < 10000; i++) {
             uint32_t rval;
             do{
-                rval=insecure_rand()&mask;
+                rval=InsecureRand32()&mask;
             }while(rval>=(uint32_t)mod);
             count += rval==0;
         }
diff --git a/src/test/versionbits_tests.cpp b/src/test/versionbits_tests.cpp
index 79405ec4d1..faa2383d14 100644
--- a/src/test/versionbits_tests.cpp
+++ b/src/test/versionbits_tests.cpp
@@ -5,7 +5,6 @@
 #include "chain.h"
 #include "versionbits.h"
 #include "test/test_bitcoin.h"
-#include "test/test_random.h"
 #include "chainparams.h"
 #include "validation.h"
 #include "consensus/params.h"
@@ -81,7 +80,7 @@ public:
 
     VersionBitsTester& TestStateSinceHeight(int height) {
         for (int i = 0; i < CHECKERS; i++) {
-            if ((insecure_rand() & ((1 << i) - 1)) == 0) {
+            if (InsecureRandBits(i) == 0) {
                 BOOST_CHECK_MESSAGE(checker[i].GetStateSinceHeightFor(vpblock.empty() ? NULL : vpblock.back()) == height, strprintf("Test %i for StateSinceHeight", num));
             }
         }
@@ -91,7 +90,7 @@ public:
 
     VersionBitsTester& TestDefined() {
         for (int i = 0; i < CHECKERS; i++) {
-            if ((insecure_rand() & ((1 << i) - 1)) == 0) {
+            if (InsecureRandBits(i) == 0) {
                 BOOST_CHECK_MESSAGE(checker[i].GetStateFor(vpblock.empty() ? NULL : vpblock.back()) == THRESHOLD_DEFINED, strprintf("Test %i for DEFINED", num));
             }
         }
@@ -101,7 +100,7 @@ public:
 
     VersionBitsTester& TestStarted() {
         for (int i = 0; i < CHECKERS; i++) {
-            if ((insecure_rand() & ((1 << i) - 1)) == 0) {
+            if (InsecureRandBits(i) == 0) {
                 BOOST_CHECK_MESSAGE(checker[i].GetStateFor(vpblock.empty() ? NULL : vpblock.back()) == THRESHOLD_STARTED, strprintf("Test %i for STARTED", num));
             }
         }
@@ -111,7 +110,7 @@ public:
 
     VersionBitsTester& TestLockedIn() {
         for (int i = 0; i < CHECKERS; i++) {
-            if ((insecure_rand() & ((1 << i) - 1)) == 0) {
+            if (InsecureRandBits(i) == 0) {
                 BOOST_CHECK_MESSAGE(checker[i].GetStateFor(vpblock.empty() ? NULL : vpblock.back()) == THRESHOLD_LOCKED_IN, strprintf("Test %i for LOCKED_IN", num));
             }
         }
@@ -121,7 +120,7 @@ public:
 
     VersionBitsTester& TestActive() {
         for (int i = 0; i < CHECKERS; i++) {
-            if ((insecure_rand() & ((1 << i) - 1)) == 0) {
+            if (InsecureRandBits(i) == 0) {
                 BOOST_CHECK_MESSAGE(checker[i].GetStateFor(vpblock.empty() ? NULL : vpblock.back()) == THRESHOLD_ACTIVE, strprintf("Test %i for ACTIVE", num));
             }
         }
@@ -131,7 +130,7 @@ public:
 
     VersionBitsTester& TestFailed() {
         for (int i = 0; i < CHECKERS; i++) {
-            if ((insecure_rand() & ((1 << i) - 1)) == 0) {
+            if (InsecureRandBits(i) == 0) {
                 BOOST_CHECK_MESSAGE(checker[i].GetStateFor(vpblock.empty() ? NULL : vpblock.back()) == THRESHOLD_FAILED, strprintf("Test %i for FAILED", num));
             }
         }
diff --git a/src/wallet/test/crypto_tests.cpp b/src/wallet/test/crypto_tests.cpp
index 0d012dacad..524a72c303 100644
--- a/src/wallet/test/crypto_tests.cpp
+++ b/src/wallet/test/crypto_tests.cpp
@@ -2,9 +2,8 @@
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
-#include "test/test_random.h"
-#include "utilstrencodings.h"
 #include "test/test_bitcoin.h"
+#include "utilstrencodings.h"
 #include "wallet/crypter.h"
 
 #include <vector>
@@ -193,7 +192,7 @@ BOOST_AUTO_TEST_CASE(passphrase) {
     std::string hash(GetRandHash().ToString());
     std::vector<unsigned char> vchSalt(8);
     GetRandBytes(&vchSalt[0], vchSalt.size());
-    uint32_t rounds = insecure_rand();
+    uint32_t rounds = InsecureRand32();
     if (rounds > 30000)
         rounds = 30000;
     TestCrypter::TestPassphrase(vchSalt, SecureString(hash.begin(), hash.end()), rounds);