Clean up TLS ciphersuite handling

Stores ciphersuites in a sorted std::vector, then lookups are done
by binary search instead of a switch lookup.

The loop that explicitly gathered all the ciphersuites out of the switch
statement can then be removed, as can Ciphersuite::all_known_ciphersuite_ids
which only existed to make the scan loop faster by avoiding having to
call by_id on the entire 0x0000-0xFFFF range.

Precomputes the result of Ciphersuite::valid at construction time.

1 files changed, 8 insertions, 31 deletions

diff --git a/src/scripts/tls_suite_info.py b/src/scripts/tls_suite_info.py
index 1f094f4b5..1d059b3f9 100755
--- a/src/scripts/tls_suite_info.py
+++ b/src/scripts/tls_suite_info.py
@@ -293,48 +293,25 @@ namespace Botan {
 
 namespace TLS {
 
-std::vector<u16bit> Ciphersuite::all_known_ciphersuite_ids()
+//static
+const std::vector<Ciphersuite>& Ciphersuite::all_known_ciphersuites()
    {
-   return std::vector<u16bit>{
+   // Note that this list of ciphersuites is ordered by id!
+   static const std::vector<Ciphersuite> g_ciphersuite_list = {
 """
 
-    for i in sorted(suites.keys()):
-        suite_info += "      0x%s,\n" % (i)
-
-    suite_info += """   };
-}
-
-Ciphersuite Ciphersuite::by_id(u16bit suite)
-   {
-   switch(suite)
-      {
-"""
-
-    """
-      Ciphersuite(u16bit ciphersuite_code,
-                  const char* sig_algo,
-                  const char* kex_algo,
-                  const char* cipher_algo,
-                  size_t cipher_keylen,
-                  size_t nonce_bytes_from_handshake,
-                  size_t nonce_bytes_from_record,
-                  const char* mac_algo,
-                  size_t mac_keylen,
-                  const char* prf_algo = "");
-    """
-
     for code in sorted(suites.keys()):
         info = suites[code]
         assert len(info) == 11
         suite_expr = 'Ciphersuite(0x%s, "%s", "%s", "%s", "%s", %d, %d, %d, "%s", %d, "%s")' % (
             code, info[0], info[2], info[3], info[4], info[5], info[6], info[7], info[8], info[9], info[10])
 
-        suite_info += "      case 0x%s:\n" % (code)
-        suite_info += "         return %s;\n\n" % (suite_expr)
+        suite_info += "      " + suite_expr + ",\n"
+        
 
-    suite_info += """      }
+    suite_info += """      };
 
-   return Ciphersuite(); // some unknown ciphersuite
+   return g_ciphersuite_list;
    }
 
 }