No longer expose strong_rand_(range|float)

3 files changed, 23 insertions, 105 deletions

diff --git a/lib/crypto/doc/src/crypto.xml b/lib/crypto/doc/src/crypto.xml
index 7a5bd62c26..36a1a2c2ee 100644
--- a/lib/crypto/doc/src/crypto.xml
+++ b/lib/crypto/doc/src/crypto.xml
@@ -660,10 +660,8 @@
         <p>Set the seed for PRNG to the given binary. This calls the
         RAND_seed function from openssl. Only use this if the system
         you are running on does not have enough "randomness" built in.
-        Normally this is when either
-        <seealso marker="#strong_rand_bytes/1">strong_rand_bytes/1</seealso>,
-        <seealso marker="#strong_rand_range/1">strong_rand_range/1</seealso> or
-        <seealso marker="#strong_rand_float/0">strong_rand_float/0</seealso>
+        Normally this is when
+        <seealso marker="#strong_rand_bytes/1">strong_rand_bytes/1</seealso>
         throws <c>low_entropy</c></p>
       </desc>
     </func>
@@ -733,40 +731,6 @@
     </func>
 
     <func>
-      <name>strong_rand_range(N) -> binary()</name>
-      <fsummary>Generate a random non-negative integer between 0 and N</fsummary>
-      <type>
-        <v>N = pos_integer() | binary()</v>
-      </type>
-      <desc>
-        <p>Generates a random non-negative integer uniformly distributed
-        in the value range <c><![CDATA[X, 0 =< X < N.]]></c>
-        Uses a cryptographically secure prng seeded and periodically mixed with operating system
-        provided entropy. By default this is the <c>BN_rand_range</c> method from OpenSSL.</p>
-        <p>Returns binary representation.</p>
-        <p>May throw exception <c>low_entropy</c> in case the random generator
-        failed due to lack of secure "randomness".</p>
-      </desc>
-    </func>
-
-    <func>
-      <name>strong_rand_float() -> X</name>
-      <fsummary>Generate a random floating point number between 0.0 and 1.0</fsummary>
-      <type>
-        <v>X = float()</v>
-      </type>
-      <desc>
-        <p>Generates a random floating pointer number uniformly distributed
-        in the value range <c><![CDATA[X, 0.0 =< X < 1.0.]]></c>
-        Uses a cryptographically secure prng seeded and periodically mixed with operating system
-        provided entropy. By default this is the <c>BN_rand_range</c> method from OpenSSL.</p>
-        <p>May throw exception <c>low_entropy</c> in case the random generator
-        failed due to lack of secure "randomness".</p>
-        <note><p>The generated values shall present no more than 51 bits of effective entropy.</p></note>
-      </desc>
-    </func>
-
-    <func>
       <name>rand_seed() -> rand:state()</name>
       <fsummary>Strong random number generation plugin state</fsummary>>
       <desc>
diff --git a/lib/crypto/src/crypto.erl b/lib/crypto/src/crypto.erl
index 4ae7a9cdd6..ad9245f8f2 100644
--- a/lib/crypto/src/crypto.erl
+++ b/lib/crypto/src/crypto.erl
@@ -30,8 +30,6 @@
 -export([hmac/3, hmac/4, hmac_init/2, hmac_update/2, hmac_final/1, hmac_final_n/2]).
 -export([cmac/3, cmac/4]).
 -export([exor/2, strong_rand_bytes/1, mod_pow/3]).
--export([strong_rand_range/1]).
--export([strong_rand_float/0]).
 -export([rand_seed/0]).
 -export([rand_seed_s/0]).
 -export([rand_uniform/2]).
@@ -290,8 +288,6 @@ stream_decrypt(State, Data0) ->
 %% RAND - pseudo random numbers using RN_ and BN_ functions in crypto lib
 %%
 -spec strong_rand_bytes(non_neg_integer()) -> binary().
--spec strong_rand_range(pos_integer() | binary()) -> binary().
--spec strong_rand_float() -> float().
 -spec rand_seed() -> rand:state().
 -spec rand_seed_s() -> rand:state().
 -spec rand_uniform(crypto_integer(), crypto_integer()) ->
@@ -305,29 +301,6 @@ strong_rand_bytes(Bytes) ->
 strong_rand_bytes_nif(_Bytes) -> ?nif_stub.
 
 
-strong_rand_range(Range) when is_integer(Range), Range > 0 ->
-    BinRange = int_to_bin(Range),
-    strong_rand_range(BinRange);
-strong_rand_range(BinRange) when is_binary(BinRange) ->
-    case strong_rand_range_nif(BinRange) of
-        false ->
-            erlang:error(low_entropy);
-        <<BinResult/binary>> ->
-            BinResult
-    end.
-strong_rand_range_nif(_BinRange) -> ?nif_stub.
-
-
-strong_rand_float() ->
-    % This could be optimized by having its own NIF
-    Sign = 0, % positive
-    Exponent = 1023, % on the interval [1.0, 2.0[
-    BinFraction = strong_rand_range(1 bsl 52), % the whole interval above
-    Fraction = bin_to_int(BinFraction),
-    <<Value:64/big-float>> = <<Sign:1, Exponent:11, Fraction:52>>,
-    Value - 1.0.
-
-
 rand_seed() ->
     rand:seed(rand_seed_s()).
 
@@ -352,6 +325,27 @@ rand_plugin_uniform(Max, State) ->
 rand_plugin_jump(State) ->
     State.
 
+strong_rand_range(Range) when is_integer(Range), Range > 0 ->
+    BinRange = int_to_bin(Range),
+    strong_rand_range(BinRange);
+strong_rand_range(BinRange) when is_binary(BinRange) ->
+    case strong_rand_range_nif(BinRange) of
+        false ->
+            erlang:error(low_entropy);
+        <<BinResult/binary>> ->
+            BinResult
+    end.
+strong_rand_range_nif(_BinRange) -> ?nif_stub.
+
+strong_rand_float() ->
+    % This could be optimized by having its own NIF
+    Sign = 0, % positive
+    Exponent = 1023, % on the interval [1.0, 2.0[
+    BinFraction = strong_rand_range(1 bsl 52), % the whole interval above
+    Fraction = bin_to_int(BinFraction),
+    <<Value:64/big-float>> = <<Sign:1, Exponent:11, Fraction:52>>,
+    Value - 1.0.
+
 
 rand_uniform(From,To) when is_binary(From), is_binary(To) ->
     case rand_uniform_nif(From,To) of
diff --git a/lib/crypto/test/crypto_SUITE.erl b/lib/crypto/test/crypto_SUITE.erl
index 482a07d634..1b7456af18 100644
--- a/lib/crypto/test/crypto_SUITE.erl
+++ b/lib/crypto/test/crypto_SUITE.erl
@@ -37,8 +37,6 @@ all() ->
      mod_pow,
      exor,
      rand_uniform,
-     strong_rand_range,
-     strong_rand_float,
      rand_plugin,
      rand_plugin_s
     ].
@@ -490,44 +488,6 @@ rand_uniform(Config) when is_list(Config) ->
     10 = byte_size(crypto:strong_rand_bytes(10)).
 
 %%--------------------------------------------------------------------
-strong_rand_range() ->
-    [{doc, "strong_rand_range testing"}].
-strong_rand_range(Config) when is_list(Config) ->
-    MaxCeiling = 1 bsl 32,
-    Ceilings = [1 | % edge case where only 0 can be generated
-                [binary:decode_unsigned(crypto:strong_rand_range(MaxCeiling), big)
-                 || _ <- lists:seq(1, 99)]],
-
-    allmap(
-      fun (Ceiling) ->
-              case Ceiling >= 0 andalso Ceiling < MaxCeiling of
-                  false ->
-                      {false, ct:fail({"Ceiling not in interval", Ceiling, 0, MaxCeiling})};
-                  true ->
-                      Samples = [binary:decode_unsigned(crypto:strong_rand_range(Ceiling), big)
-                                 || _ <- lists:seq(1, 100)],
-                      allmap(
-                        fun (V) ->
-                                (V >= 0 andalso V < Ceiling)
-                                orelse {false, ct:fail({"Sample not in interval", V, 0, Ceiling})}
-                        end,
-                        Samples)
-              end
-      end,
-      Ceilings).
-
-strong_rand_float() ->
-    [{doc, "strong_rand_float testing"}].
-strong_rand_float(Config) when is_list(Config) ->
-    Samples = [crypto:strong_rand_float() || _ <- lists:seq(1, 10000)],
-    allmap(
-       fun (V) ->
-               (V >= 0.0 andalso V < 1.0)
-               orelse {false, ct:fail({"Not in interval", V, 0.0, 1.0})}
-        end,
-       Samples).
-
-%%--------------------------------------------------------------------
 rand_plugin() ->
     [{doc, "crypto rand plugin testing (implicit state / process dictionary)"}].
 rand_plugin(Config) when is_list(Config) ->