extensions: optimized gid_to_ext_entry() map on known extensions

Signed-off-by: Nikos Mavrogiannopoulos <nmav@redhat.com>

diff --git a/lib/gnutls_int.h b/lib/gnutls_int.h
index d7a4e7182dbe29ca3ff922d2ca85ea425a94b5b9..b19eb987ed1bd4d7bb7ce967446d11f1bd7bc8e5 100644 (file)
--- a/lib/gnutls_int.h
+++ b/lib/gnutls_int.h
@@ -291,7 +291,6 @@ typedef enum extensions_t {
        GNUTLS_EXTENSION_SRTP,
        GNUTLS_EXTENSION_HEARTBEAT,
        GNUTLS_EXTENSION_ALPN,
-       GNUTLS_EXTENSION_DUMBFW,
        GNUTLS_EXTENSION_ETM,
        GNUTLS_EXTENSION_EXT_MASTER_SECRET,
        GNUTLS_EXTENSION_SESSION_TICKET,
@@ -301,7 +300,8 @@ typedef enum extensions_t {
        GNUTLS_EXTENSION_SAFE_RENEGOTIATION,
        GNUTLS_EXTENSION_SERVER_NAME,
        GNUTLS_EXTENSION_COOKIE,
-       GNUTLS_EXTENSION_MAX = GNUTLS_EXTENSION_COOKIE
+       GNUTLS_EXTENSION_DUMBFW, /* this must always be the last */
+       GNUTLS_EXTENSION_MAX /* not real extension - used for iterators */
 } extensions_t;
 
 #define GNUTLS_EXTENSION_MAX_VALUE 31

diff --git a/lib/hello_ext.c b/lib/hello_ext.c
index 99412335e96d0c03bdef1dc282acb69ce4ae37dd..c582aecc95e1b2878ea263a7aab2e0f9c67aee40 100644 (file)
--- a/lib/hello_ext.c
+++ b/lib/hello_ext.c
@@ -54,44 +54,42 @@
 static void
 unset_ext_data(gnutls_session_t session, const struct hello_ext_entry_st *, unsigned idx);
 
-static int ext_register(hello_ext_entry_st * mod);
 static void unset_resumed_ext_data(gnutls_session_t session, const struct hello_ext_entry_st *, unsigned idx);
 
 static hello_ext_entry_st const *extfunc[MAX_EXT_TYPES+1] = {
-       &ext_mod_max_record_size,
-       &ext_mod_ext_master_secret,
-       &ext_mod_supported_versions,
-       &ext_mod_post_handshake,
-       &ext_mod_etm,
+       [GNUTLS_EXTENSION_MAX_RECORD_SIZE] = &ext_mod_max_record_size,
+       [GNUTLS_EXTENSION_EXT_MASTER_SECRET] = &ext_mod_ext_master_secret,
+       [GNUTLS_EXTENSION_SUPPORTED_VERSIONS] = &ext_mod_supported_versions,
+       [GNUTLS_EXTENSION_POST_HANDSHAKE] = &ext_mod_post_handshake,
+       [GNUTLS_EXTENSION_ETM] = &ext_mod_etm,
 #ifdef ENABLE_OCSP
-       &ext_mod_status_request,
+       [GNUTLS_EXTENSION_STATUS_REQUEST] = &ext_mod_status_request,
 #endif
-       &ext_mod_server_name,
-       &ext_mod_sr,
+       [GNUTLS_EXTENSION_SERVER_NAME] = &ext_mod_server_name,
+       [GNUTLS_EXTENSION_SAFE_RENEGOTIATION] = &ext_mod_sr,
 #ifdef ENABLE_SRP
-       &ext_mod_srp,
+       [GNUTLS_EXTENSION_SRP] = &ext_mod_srp,
 #endif
 #ifdef ENABLE_HEARTBEAT
-       &ext_mod_heartbeat,
+       [GNUTLS_EXTENSION_HEARTBEAT] = &ext_mod_heartbeat,
 #endif
 #ifdef ENABLE_SESSION_TICKETS
-       &ext_mod_session_ticket,
+       [GNUTLS_EXTENSION_SESSION_TICKET] = &ext_mod_session_ticket,
 #endif
-       &ext_mod_supported_ecc,
-       &ext_mod_supported_ecc_pf,
-       &ext_mod_sig,
-       &ext_mod_key_share,
-       &ext_mod_cookie,
+       [GNUTLS_EXTENSION_SUPPORTED_ECC] = &ext_mod_supported_ecc,
+       [GNUTLS_EXTENSION_SUPPORTED_ECC_PF] = &ext_mod_supported_ecc_pf,
+       [GNUTLS_EXTENSION_SIGNATURE_ALGORITHMS] = &ext_mod_sig,
+       [GNUTLS_EXTENSION_KEY_SHARE] = &ext_mod_key_share,
+       [GNUTLS_EXTENSION_COOKIE] = &ext_mod_cookie,
 #ifdef ENABLE_DTLS_SRTP
-       &ext_mod_srtp,
+       [GNUTLS_EXTENSION_SRTP] = &ext_mod_srtp,
 #endif
 #ifdef ENABLE_ALPN
-       &ext_mod_alpn,
+       [GNUTLS_EXTENSION_ALPN] = &ext_mod_alpn,
 #endif
        /* This must be the last extension registered.
         */
-       &ext_mod_dumbfw,
-       NULL
+       [GNUTLS_EXTENSION_DUMBFW] = &ext_mod_dumbfw,
 };
 
 static const hello_ext_entry_st *
@@ -99,19 +97,15 @@ gid_to_ext_entry(gnutls_session_t session, extensions_t id)
 {
        unsigned i;
 
+       assert(id < MAX_EXT_TYPES);
+
        for (i=0;i<session->internals.rexts_size;i++) {
                if (session->internals.rexts[i].gid == id) {
                        return &session->internals.rexts[i];
                }
        }
 
-       for (i = 0; extfunc[i] != NULL; i++) {
-               if (extfunc[i]->gid == id) {
-                       return extfunc[i];
-               }
-       }
-
-       return NULL;
+       return extfunc[id];
 }
 
 static const hello_ext_entry_st *
@@ -127,7 +121,10 @@ tls_id_to_ext_entry(gnutls_session_t session, uint16_t tls_id, gnutls_ext_parse_
                }
        }
 
-       for (i = 0; extfunc[i] != NULL; i++) {
+       for (i = 0; i < MAX_EXT_TYPES; i++) {
+               if (!extfunc[i])
+                       continue;
+
                if (extfunc[i]->tls_id == tls_id) {
                        e = extfunc[i];
                        goto done;
@@ -157,9 +154,13 @@ const char *gnutls_ext_get_name(unsigned int ext)
 {
        size_t i;
 
-       for (i = 0; extfunc[i] != NULL; i++)
+       for (i = 0; i < MAX_EXT_TYPES; i++) {
+               if (!extfunc[i])
+                       continue;
+
                if (extfunc[i]->tls_id == ext)
                        return extfunc[i]->name;
+       }
 
        return NULL;
 }
@@ -175,7 +176,10 @@ static unsigned tls_id_to_gid(gnutls_session_t session, unsigned tls_id)
                        return session->internals.rexts[i].gid;
        }
 
-       for (i = 0; extfunc[i] != NULL; i++) {
+       for (i = 0; i < MAX_EXT_TYPES; i++) {
+               if (!extfunc[i])
+                       continue;
+
                if (extfunc[i]->tls_id == tls_id)
                        return extfunc[i]->gid;
        }
@@ -360,9 +364,12 @@ _gnutls_gen_hello_extensions(gnutls_session_t session,
                                     session, ctx.ext->name, (int)ctx.ext->tls_id, ret-4);
        }
 
-       /* send_extension() ensures we don't send duplicates, in case
+       /* hello_ext_send() ensures we don't send duplicates, in case
         * of overriden extensions */
-       for (i = 0; extfunc[i] != NULL; i++) {
+       for (i = 0; i < MAX_EXT_TYPES; i++) {
+               if (!extfunc[i])
+                       continue;
+
                ctx.ext = extfunc[i];
                ret = _gnutls_extv_append(buf, extfunc[i]->tls_id,
                                          &ctx, hello_ext_send);
@@ -391,7 +398,11 @@ int _gnutls_hello_ext_init(void)
 void _gnutls_hello_ext_deinit(void)
 {
        unsigned i;
-       for (i = 0; extfunc[i] != NULL; i++) {
+
+       for (i = 0; i < MAX_EXT_TYPES; i++) {
+               if (!extfunc[i])
+                       continue;
+
                if (extfunc[i]->free_struct != 0) {
                        gnutls_free((void*)extfunc[i]->name);
                        gnutls_free((void*)extfunc[i]);
@@ -400,24 +411,6 @@ void _gnutls_hello_ext_deinit(void)
        }
 }
 
-static
-int ext_register(hello_ext_entry_st * mod)
-{
-       unsigned i = 0;
-
-       while(extfunc[i] != NULL) {
-               i++;
-       }
-
-       if (i >= MAX_EXT_TYPES-1) {
-               return gnutls_assert_val(GNUTLS_E_INTERNAL_ERROR);
-       }
-
-       extfunc[i] = mod;
-       extfunc[i+1] = NULL;
-       return GNUTLS_E_SUCCESS;
-}
-
 /* Packing of extension data (for use in resumption) */
 static int pack_extension(gnutls_session_t session, const hello_ext_entry_st *extp,
                          gnutls_buffer_st *packed)
@@ -689,11 +682,13 @@ gnutls_ext_register(const char *name, int id, gnutls_ext_parse_type_t parse_type
                    gnutls_ext_unpack_func unpack_func)
 {
        hello_ext_entry_st *tmp_mod;
-       int ret;
        unsigned i;
        unsigned gid = GNUTLS_EXTENSION_MAX+1;
 
-       for (i = 0; extfunc[i] != NULL; i++) {
+       for (i = 0; i < MAX_EXT_TYPES; i++) {
+               if (!extfunc[i])
+                       continue;
+
                if (extfunc[i]->tls_id == id)
                        return gnutls_assert_val(GNUTLS_E_ALREADY_REGISTERED);
 
@@ -701,7 +696,7 @@ gnutls_ext_register(const char *name, int id, gnutls_ext_parse_type_t parse_type
                        gid = extfunc[i]->gid + 1;
        }
 
-       if (gid > GNUTLS_EXTENSION_MAX_VALUE)
+       if (gid > GNUTLS_EXTENSION_MAX_VALUE || gid >= sizeof(extfunc)/sizeof(extfunc[0]))
                return gnutls_assert_val(GNUTLS_E_MEMORY_ERROR);
 
        tmp_mod = gnutls_calloc(1, sizeof(*tmp_mod));
@@ -720,12 +715,10 @@ gnutls_ext_register(const char *name, int id, gnutls_ext_parse_type_t parse_type
        tmp_mod->unpack_func = unpack_func;
        tmp_mod->validity = GNUTLS_EXT_FLAG_CLIENT_HELLO|GNUTLS_EXT_FLAG_TLS12_SERVER_HELLO|GNUTLS_EXT_FLAG_EE;
 
-       ret = ext_register(tmp_mod);
-       if (ret < 0) {
-               gnutls_free((void*)tmp_mod->name);
-               gnutls_free(tmp_mod);
-       }
-       return ret;
+       assert(extfunc[gid] == NULL);
+       extfunc[gid] = tmp_mod;
+
+       return 0;
 }
 
 #define VALIDITY_MASK (GNUTLS_EXT_FLAG_CLIENT_HELLO|GNUTLS_EXT_FLAG_TLS12_SERVER_HELLO| \
@@ -780,7 +773,10 @@ gnutls_session_ext_register(gnutls_session_t session,
 
        /* reject handling any extensions which modify the TLS handshake
         * in any way, or are mapped to an exported API. */
-       for (i = 0; extfunc[i] != NULL; i++) {
+       for (i = 0; i < GNUTLS_EXTENSION_MAX; i++) {
+               if (!extfunc[i])
+                       continue;
+
                if (extfunc[i]->tls_id == id) {
                        if (!(flags & GNUTLS_EXT_FLAG_OVERRIDE_INTERNAL)) {
                                return gnutls_assert_val(GNUTLS_E_ALREADY_REGISTERED);