Limit FQDN in DiameterURI to 255 octets

As for the port number in the parent commit, a FQDN can't be arbitrarily
long, at most 255 octets. Make decode fail if it's more.

1 files changed, 6 insertions, 11 deletions

diff --git a/lib/diameter/src/base/diameter_types.erl b/lib/diameter/src/base/diameter_types.erl
index 96407efc09..87a0f0663d 100644
--- a/lib/diameter/src/base/diameter_types.erl
+++ b/lib/diameter/src/base/diameter_types.erl
@@ -93,7 +93,7 @@
     case diameter_codec:getopt(string_decode) of
         true ->
             binary_to_list(Bin);
-        _ ->
+        false ->
             Bin
     end;
 
@@ -565,7 +565,7 @@ msb(false) -> ?TIME_2036.
 
 scan_uri(Bin) ->
     RE = "^(aaas?)://"
-         "([-a-zA-Z0-9.]+)"
+         "([-a-zA-Z0-9.]{1,255})"
          "(:0{0,5}([0-9]{1,5}))?"
          "(;transport=(tcp|sctp|udp))?"
          "(;protocol=(diameter|radius|tacacs\\+))?$",
@@ -575,6 +575,9 @@ scan_uri(Bin) ->
     %% [0-9]+ and it's not inconceivable that a value might be padded.
     %% Don't fantasize about this padding being more than the number
     %% of digits in the port number proper.
+    %%
+    %% Similarly, a FQDN can't be arbitrarily long: at most 255
+    %% octets.
     {match, [A, DN, PN, T, P]} = re:run(Bin,
                                         RE,
                                         [{capture, [1,2,4,6,8], binary}]),
@@ -583,7 +586,7 @@ scan_uri(Bin) ->
     PortNr = to_int(PN, PN0),
     0 = PortNr bsr 16,  %% assert
     #diameter_uri{type = Type,
-                  fqdn = from_bin(DN),
+                  fqdn = 'OctetString'(decode, DN),
                   port = PortNr,
                   transport = to_atom(T, T0),
                   protocol = to_atom(P, diameter)}.
@@ -596,14 +599,6 @@ defaults(6733, aaa) ->
 defaults(6733, aaas) ->
     {5658, tcp}.
 
-from_bin(B) ->
-    case diameter_codec:getopt(string_decode) of
-        true ->
-            binary_to_list(B);
-        false ->
-            B
-    end.
-
 to_int(<<>>, N) ->
     N;
 to_int(B, _) ->