beam_lib, compile: Replace use of deprecated crypto functions

Since both the STDLIB and compiler applications turn warnings
into errors, we must stop using the old deprecated crypto functions.

While we are at it, generalize the format of the key tuple returned
by beam_lib:make_crypto_key/2 to facilitate introducing new crypto
methods in the future. Change the format to:

  {Type,Key,IV,BlockSize}

where Type, Key, and IV are the first three arguments for either
crypto:block_encrypt4/ or crypto:block_decrypt/4, and BlockSize
is the block size for the crypto algorithm (it is needed to properly
pad the plaintext blocks before encryption).

4 files changed, 28 insertions, 10 deletions

diff --git a/lib/compiler/src/compile.erl b/lib/compiler/src/compile.erl
index 745f1d5cf9..2ca403de54 100644
--- a/lib/compiler/src/compile.erl
+++ b/lib/compiler/src/compile.erl
@@ -1197,9 +1197,9 @@ abstract_code(#compile{code=Code,options=Opts,ofile=OFile}) ->
 
 encrypt_abs_code(Abstr, Key0) ->
     try
-	{Mode,RealKey} = generate_key(Key0),
+	RealKey = generate_key(Key0),
 	case start_crypto() of
-	    ok -> {ok,encrypt(Mode, RealKey, Abstr)};
+	    ok -> {ok,encrypt(RealKey, Abstr)};
 	    {error,_}=E -> E
 	end
     catch
@@ -1216,19 +1216,19 @@ start_crypto() ->
 	    {error,[{none,?MODULE,no_crypto}]}
     end.
 
-generate_key({Mode,String}) when is_atom(Mode), is_list(String) ->
-    {Mode,beam_lib:make_crypto_key(Mode, String)};
+generate_key({Type,String}) when is_atom(Type), is_list(String) ->
+    beam_lib:make_crypto_key(Type, String);
 generate_key(String) when is_list(String) ->
     generate_key({des3_cbc,String}).
 
-encrypt(des3_cbc=Mode, {K1,K2,K3, IVec}, Bin0) ->
-    Bin1 = case byte_size(Bin0) rem 8 of
+encrypt({des3_cbc=Type,Key,IVec,BlockSize}, Bin0) ->
+    Bin1 = case byte_size(Bin0) rem BlockSize of
 	       0 -> Bin0;
-	       N -> list_to_binary([Bin0,random_bytes(8-N)])
+	       N -> list_to_binary([Bin0,random_bytes(BlockSize-N)])
 	   end,
-    Bin = crypto:des3_cbc_encrypt(K1, K2, K3, IVec, Bin1),
-    ModeString = atom_to_list(Mode),
-    list_to_binary([0,length(ModeString),ModeString,Bin]).
+    Bin = crypto:block_encrypt(Type, Key, IVec, Bin1),
+    TypeString = atom_to_list(Type),
+    list_to_binary([0,length(TypeString),TypeString,Bin]).
 
 random_bytes(N) ->
     {A,B,C} = now(),
diff --git a/lib/compiler/test/compile_SUITE.erl b/lib/compiler/test/compile_SUITE.erl
index 229e5a98a1..c635d13c89 100644
--- a/lib/compiler/test/compile_SUITE.erl
+++ b/lib/compiler/test/compile_SUITE.erl
@@ -492,6 +492,16 @@ encrypted_abstr_1(Simple, Target) ->
     ?line {error,beam_lib,{key_missing_or_invalid,"simple.beam",abstract_code}} =
 	beam_lib:chunks("simple.beam", [abstract_code]),
     ?line ok = file:set_cwd(OldCwd),
+
+    %% Test key compatibility by reading a BEAM file produced before
+    %% the update to the new crypto functions.
+    install_crypto_key("an old key"),
+    KeyCompat = filename:join(filename:dirname(Simple),
+			      "key_compatibility"),
+    {ok,{key_compatibility,[Chunk]}} = beam_lib:chunks(KeyCompat,
+						       [abstract_code]),
+    {abstract_code,{raw_abstract_v1,_}} = Chunk,
+
     ok.
 
 
diff --git a/lib/compiler/test/compile_SUITE_data/key_compatibility.beam b/lib/compiler/test/compile_SUITE_data/key_compatibility.beam
new file mode 100644
index 0000000000..28329d2423
--- /dev/null
+++ b/lib/compiler/test/compile_SUITE_data/key_compatibility.beam
diff --git a/lib/compiler/test/compile_SUITE_data/key_compatibility.erl b/lib/compiler/test/compile_SUITE_data/key_compatibility.erl
new file mode 100644
index 0000000000..e2931f1b12
--- /dev/null
+++ b/lib/compiler/test/compile_SUITE_data/key_compatibility.erl
@@ -0,0 +1,8 @@
+-module(key_compatibility).
+-export([main/0]).
+
+%% Compile like this:
+%%  erlc +'{debug_info_key,"an old key"}' key_compatibility.erl
+
+main() ->
+    ok.