Mark Skein_512 with the BOTAN_DLL macro

Add a comment that the limitation of the personalization string
being a maximum of 64 characters is due to the implementation and
not the specification (but it makes it easy to implement, and in
this particular case 64 characters is probably fine).

Add some tests for the personalization option, generated by the
Skein reference implementation.

Disable stripping whitespace in checks/misc.cpp:strip - it strips
the personalization tag, which breaks the test, and isn't needed
otherwise because the test files are well-formed.

1 files changed, 6 insertions, 0 deletions

diff --git a/src/hash/skein/skein_512.cpp b/src/hash/skein/skein_512.cpp
index c8a26ae82..eaef641ed 100644
--- a/src/hash/skein/skein_512.cpp
+++ b/src/hash/skein/skein_512.cpp
@@ -132,6 +132,7 @@ void initial_block(u64bit H[9], u64bit T[3], u32bit output_bits,
    {
    clear_mem(H, 9);
 
+   // ASCII("SHA3") followed by version (0x0001) code
    byte config_str[32] = { 0x53, 0x48, 0x41, 0x33, 0x01, 0x00, 0 };
    store_le(output_bits, config_str + 8);
 
@@ -140,6 +141,11 @@ void initial_block(u64bit H[9], u64bit T[3], u32bit output_bits,
 
    if(personalization != "")
       {
+      /*
+        This is a limitation of this implementation, and not of the
+        algorithm specification. Could be fixed relatively easily, but
+        doesn't seem worth the trouble.
+      */
       if(personalization.length() > 64)
          throw Invalid_Argument("Skein personalization must be <= 64 bytes");