X-Git-Url: http://git.silcnet.org/gitweb/?a=blobdiff_plain;f=lib%2Fsilccrypt%2Fsilchmac.c;h=86754f230c977682c5ce2547ec94c94f25586d39;hb=e7b6c157b80152bf9fb9266e6bdd93f9fb0db776;hp=2c9147a84bbf709e4ff6c669f11b403a5a49fa73;hpb=fb8dbc2d9cd7ff5d197654f873ac18aa6ef9c5e3;p=silc.git

diff --git a/lib/silccrypt/silchmac.c b/lib/silccrypt/silchmac.c
index 2c9147a8..86754f23 100644
--- a/lib/silccrypt/silchmac.c
+++ b/lib/silccrypt/silchmac.c
@@ -2,15 +2,14 @@
 
   silchmac.c
 
-  Author: Pekka Riikonen <priikone@poseidon.pspt.fi>
+  Author: Pekka Riikonen <priikone@silcnet.org>
 
-  Copyright (C) 1997 - 2001 Pekka Riikonen
+  Copyright (C) 1999 - 2007 Pekka Riikonen
 
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
-  the Free Software Foundation; either version 2 of the License, or
-  (at your option) any later version.
-  
+  the Free Software Foundation; version 2 of the License.
+
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
@@ -19,32 +18,93 @@
 */
 /* $Id$ */
 
-#include "silcincludes.h"
+#include "silc.h"
+
+/* HMAC context */
+struct SilcHmacStruct {
+  SilcHmacObject *hmac;
+  SilcHash hash;
+  unsigned char inner_pad[64];
+  unsigned char outer_pad[64];
+  unsigned char *key;
+  unsigned int key_len        : 31;
+  unsigned int allocated_hash : 1;   /* TRUE if the hash was allocated */
+};
 
+#ifndef SILC_SYMBIAN
 /* List of dynamically registered HMACs. */
 SilcDList silc_hmac_list = NULL;
+#endif /* SILC_SYMBIAN */
 
 /* Default hmacs for silc_hmac_register_default(). */
-SilcHmacObject silc_default_hmacs[] =
+const SilcHmacObject silc_default_hmacs[] =
 {
+  { "hmac-sha256-96", 12 },
+  { "hmac-sha512-96", 12 },
   { "hmac-sha1-96", 12 },
   { "hmac-md5-96", 12 },
+  { "hmac-sha256", 32 },
+  { "hmac-sha512", 64 },
   { "hmac-sha1", 20 },
   { "hmac-md5", 16 },
 
   { NULL, 0 }
 };
 
-/* Registers a new HMAC into the SILC. This function is used at the
-   initialization of the SILC. */
+static void silc_hmac_init_internal(SilcHmac hmac, unsigned char *key,
+				    SilcUInt32 key_len)
+{
+  SilcHash hash = hmac->hash;
+  SilcUInt32 block_len;
+  unsigned char hvalue[SILC_HASH_MAXLEN];
+  int i;
 
-bool silc_hmac_register(SilcHmacObject *hmac)
+  memset(hmac->inner_pad, 0, sizeof(hmac->inner_pad));
+  memset(hmac->outer_pad, 0, sizeof(hmac->outer_pad));
+
+  block_len = silc_hash_block_len(hash);
+
+  /* If the key length is more than block size of the hash function, the
+     key is hashed. */
+  if (key_len > block_len) {
+    silc_hash_make(hash, key, key_len, hvalue);
+    key = hvalue;
+    key_len = silc_hash_len(hash);
+  }
+
+  /* Copy the key into the pads */
+  memcpy(hmac->inner_pad, key, key_len);
+  memcpy(hmac->outer_pad, key, key_len);
+
+  /* XOR the key with pads */
+  for (i = 0; i < block_len; i++) {
+    hmac->inner_pad[i] ^= 0x36;
+    hmac->outer_pad[i] ^= 0x5c;
+  }
+}
+
+/* Registers a new HMAC */
+
+SilcBool silc_hmac_register(const SilcHmacObject *hmac)
 {
+#ifndef SILC_SYMBIAN
   SilcHmacObject *new;
 
   SILC_LOG_DEBUG(("Registering new HMAC `%s'", hmac->name));
 
+  /* Check for existing */
+  if (silc_hmac_list) {
+    SilcHmacObject *entry;
+    silc_dlist_start(silc_hmac_list);
+    while ((entry = silc_dlist_get(silc_hmac_list)) != SILC_LIST_END) {
+      if (!strcmp(entry->name, hmac->name))
+	return FALSE;
+    }
+  }
+
   new = silc_calloc(1, sizeof(*new));
+  if (!new)
+    return FALSE;
   new->name = strdup(hmac->name);
   new->len = hmac->len;
 
@@ -53,13 +113,15 @@ bool silc_hmac_register(SilcHmacObject *hmac)
     silc_hmac_list = silc_dlist_init();
   silc_dlist_add(silc_hmac_list, new);
 
+#endif /* SILC_SYMBIAN */
   return TRUE;
 }
 
-/* Unregister a HMAC from the SILC. */
+/* Unregister a HMAC */
 
-bool silc_hmac_unregister(SilcHmacObject *hmac)
+SilcBool silc_hmac_unregister(SilcHmacObject *hmac)
 {
+#ifndef SILC_SYMBIAN
   SilcHmacObject *entry;
 
   SILC_LOG_DEBUG(("Unregistering HMAC"));
@@ -71,6 +133,8 @@ bool silc_hmac_unregister(SilcHmacObject *hmac)
   while ((entry = silc_dlist_get(silc_hmac_list)) != SILC_LIST_END) {
     if (hmac == SILC_ALL_HMACS || entry == hmac) {
       silc_dlist_del(silc_hmac_list, entry);
+      silc_free(entry->name);
+      silc_free(entry);
 
       if (silc_dlist_count(silc_hmac_list) == 0) {
 	silc_dlist_uninit(silc_hmac_list);
@@ -81,20 +145,35 @@ bool silc_hmac_unregister(SilcHmacObject *hmac)
     }
   }
 
+#endif /* SILC_SYMBIAN */
   return FALSE;
 }
 
-/* Function that registers all the default hmacs (all builtin ones). 
-   The application may use this to register the default hmacs if
-   specific hmacs in any specific order is not wanted. */
+/* Register default HMACs */
 
-bool silc_hmac_register_default(void)
+SilcBool silc_hmac_register_default(void)
 {
-  int i;
+  /* We use builtin HMACs */
+  return TRUE;
+}
 
-  for (i = 0; silc_default_hmacs[i].name; i++)
-    silc_hmac_register(&(silc_default_hmacs[i]));
+/* Unregister all HMACs */
 
+SilcBool silc_hmac_unregister_all(void)
+{
+#ifndef SILC_SYMBIAN
+  SilcHmacObject *entry;
+
+  if (!silc_hmac_list)
+    return FALSE;
+
+  silc_dlist_start(silc_hmac_list);
+  while ((entry = silc_dlist_get(silc_hmac_list)) != SILC_LIST_END) {
+    silc_hmac_unregister(entry);
+    if (!silc_hmac_list)
+      break;
+  }
+#endif /* SILC_SYMBIAN */
   return TRUE;
 }
 
@@ -103,14 +182,17 @@ bool silc_hmac_register_default(void)
    of the HMAC.  If it is NULL then the hash function is allocated and
    the name of the hash algorithm is derived from the `name'. */
 
-bool silc_hmac_alloc(char *name, SilcHash hash, SilcHmac *new_hmac)
+SilcBool silc_hmac_alloc(const char *name, SilcHash hash, SilcHmac *new_hmac)
 {
-  SilcHmacObject *entry;
+  SilcHmacObject *entry = NULL;
+  int i;
 
   SILC_LOG_DEBUG(("Allocating new HMAC"));
 
   /* Allocate the new object */
   *new_hmac = silc_calloc(1, sizeof(**new_hmac));
+  if (!(*new_hmac))
+    return FALSE;
 
   if (!hash) {
     char *tmp = strdup(name), *hname;
@@ -123,6 +205,8 @@ bool silc_hmac_alloc(char *name, SilcHash hash, SilcHmac *new_hmac)
 
     if (!silc_hash_alloc(hname, &hash)) {
       silc_free(tmp);
+      silc_free(*new_hmac);
+      *new_hmac = NULL;
       return FALSE;
     }
 
@@ -132,16 +216,31 @@ bool silc_hmac_alloc(char *name, SilcHash hash, SilcHmac *new_hmac)
 
   (*new_hmac)->hash = hash;
 
+#ifndef SILC_SYMBIAN
+  /* Check registered list of HMACs */
   if (silc_hmac_list) {
     silc_dlist_start(silc_hmac_list);
     while ((entry = silc_dlist_get(silc_hmac_list)) != SILC_LIST_END) {
       if (!strcmp(entry->name, name)) {
-	(*new_hmac)->hmac = entry; 
+	(*new_hmac)->hmac = entry;
+	return TRUE;
+      }
+    }
+  }
+#endif /* SILC_SYMBIAN */
+
+  if (!entry) {
+    /* Check builtin list of HMACs */
+    for (i = 0; silc_default_hmacs[i].name; i++) {
+      if (!strcmp(silc_default_hmacs[i].name, name)) {
+	(*new_hmac)->hmac = (SilcHmacObject *)&(silc_default_hmacs[i]);
 	return TRUE;
       }
     }
   }
 
+  silc_free(*new_hmac);
+  *new_hmac = NULL;
   return FALSE;
 }
 
@@ -152,26 +251,48 @@ void silc_hmac_free(SilcHmac hmac)
   if (hmac) {
     if (hmac->allocated_hash)
       silc_hash_free(hmac->hash);
+
+    if (hmac->key) {
+      memset(hmac->key, 0, hmac->key_len);
+      silc_free(hmac->key);
+    }
+
     silc_free(hmac);
   }
 }
 
 /* Returns the length of the MAC that the HMAC will produce. */
 
-uint32 silc_hmac_len(SilcHmac hmac)
+SilcUInt32 silc_hmac_len(SilcHmac hmac)
 {
   return hmac->hmac->len;
 }
 
+/* Get hash context */
+
+SilcHash silc_hmac_get_hash(SilcHmac hmac)
+{
+  return hmac->hash;
+}
+
+/* Return name of hmac */
+
+const char *silc_hmac_get_name(SilcHmac hmac)
+{
+  return hmac->hmac->name;
+}
+
 /* Returns TRUE if HMAC `name' is supported. */
 
-bool silc_hmac_is_supported(const char *name)
+SilcBool silc_hmac_is_supported(const char *name)
 {
   SilcHmacObject *entry;
+  int i;
 
   if (!name)
     return FALSE;
-  
+
+#ifndef SILC_SYMBIAN
   if (silc_hmac_list) {
     silc_dlist_start(silc_hmac_list);
     while ((entry = silc_dlist_get(silc_hmac_list)) != SILC_LIST_END) {
@@ -179,6 +300,11 @@ bool silc_hmac_is_supported(const char *name)
 	return TRUE;
     }
   }
+#endif /* SILC_SYMBIAN */
+
+  for (i = 0; silc_default_hmacs[i].name; i++)
+    if (!strcmp(silc_default_hmacs[i].name, name))
+      return TRUE;
 
   return FALSE;
 }
@@ -187,23 +313,47 @@ bool silc_hmac_is_supported(const char *name)
 
 char *silc_hmac_get_supported()
 {
-  SilcHmacObject *entry;
+  SilcHmacObject *entry, *entry2;
   char *list = NULL;
-  int len;
+  int len = 0, i;
 
-  len = 0;
+#ifndef SILC_SYMBIAN
   if (silc_hmac_list) {
     silc_dlist_start(silc_hmac_list);
     while ((entry = silc_dlist_get(silc_hmac_list)) != SILC_LIST_END) {
       len += strlen(entry->name);
       list = silc_realloc(list, len + 1);
-      
-      memcpy(list + (len - strlen(entry->name)), 
+
+      memcpy(list + (len - strlen(entry->name)),
 	     entry->name, strlen(entry->name));
       memcpy(list + len, ",", 1);
       len++;
     }
   }
+#endif /* SILC_SYMBIAN */
+
+
+  for (i = 0; silc_default_hmacs[i].name; i++) {
+    entry = (SilcHmacObject *)&(silc_default_hmacs[i]);
+
+    if (silc_hmac_list) {
+      silc_dlist_start(silc_hmac_list);
+      while ((entry2 = silc_dlist_get(silc_hmac_list)) != SILC_LIST_END) {
+	if (!strcmp(entry2->name, entry->name))
+	  break;
+      }
+      if (entry2)
+	continue;
+    }
+
+    len += strlen(entry->name);
+    list = silc_realloc(list, len + 1);
+
+    memcpy(list + (len - strlen(entry->name)),
+	   entry->name, strlen(entry->name));
+    memcpy(list + len, ",", 1);
+    len++;
+  }
 
   list[len - 1] = 0;
 
@@ -213,112 +363,122 @@ char *silc_hmac_get_supported()
 /* Sets the HMAC key used in the HMAC creation */
 
 void silc_hmac_set_key(SilcHmac hmac, const unsigned char *key,
-		       uint32 key_len)
+		       SilcUInt32 key_len)
 {
   if (hmac->key) {
     memset(hmac->key, 0, hmac->key_len);
     silc_free(hmac->key);
   }
-  hmac->key = silc_calloc(key_len, sizeof(unsigned char));
+  hmac->key = silc_malloc(key_len);
+  if (!hmac->key)
+    return;
   hmac->key_len = key_len;
   memcpy(hmac->key, key, key_len);
 }
 
-/* Creates the HMAC. The created keyed hash value is returned to 
-   return_hash argument. */
+/* Return HMAC key */
 
-void silc_hmac_make_internal(SilcHmac hmac, unsigned char *data,
-			     uint32 data_len, unsigned char *key,
-			     uint32 key_len, unsigned char *return_hash)
+const unsigned char *silc_hmac_get_key(SilcHmac hmac, SilcUInt32 *key_len)
 {
-  SilcHash hash = hmac->hash;
-  unsigned char inner_pad[hash->hash->block_len + 1];
-  unsigned char outer_pad[hash->hash->block_len + 1];
-  unsigned char hvalue[hash->hash->hash_len];
-  unsigned char mac[128];
-  void *hash_context;
-  int i;
-
-  SILC_LOG_DEBUG(("Making HMAC for message"));
-
-  hash_context = silc_calloc(1, hash->hash->context_len());
-
-  memset(inner_pad, 0, sizeof(inner_pad));
-  memset(outer_pad, 0, sizeof(outer_pad));
-
-  /* If the key length is more than block size of the hash function, the
-     key is hashed. */
-  if (key_len > hash->hash->block_len) {
-    silc_hash_make(hash, key, key_len, hvalue);
-    key = hvalue;
-    key_len = hash->hash->hash_len;
-  }
-
-  /* Copy the key into the pads */
-  memcpy(inner_pad, key, key_len);
-  memcpy(outer_pad, key, key_len);
-
-  /* XOR the key with pads */
-  for (i = 0; i < hash->hash->block_len; i++) {
-    inner_pad[i] ^= 0x36;
-    outer_pad[i] ^= 0x5c;
-  }
-
-  /* Do the HMAC transform (too bad I can't do make_hash directly, sigh) */
-  hash->hash->init(hash_context);
-  hash->hash->update(hash_context, inner_pad, hash->hash->block_len);
-  hash->hash->update(hash_context, data, data_len);
-  hash->hash->final(hash_context, mac);
-  hash->hash->init(hash_context);
-  hash->hash->update(hash_context, outer_pad, hash->hash->block_len);
-  hash->hash->update(hash_context, mac, hash->hash->hash_len);
-  hash->hash->final(hash_context, mac);
-  memcpy(return_hash, mac, hmac->hmac->len);
-  memset(mac, 0, sizeof(mac));
-  silc_free(hash_context);
+  if (key_len)
+    *key_len = hmac->key_len;
+  return (const unsigned char *)hmac->key;
 }
 
 /* Create the HMAC. This is thee make_hmac function pointer.  This
    uses the internal key set with silc_hmac_set_key. */
 
 void silc_hmac_make(SilcHmac hmac, unsigned char *data,
-		    uint32 data_len, unsigned char *return_hash,
-		    uint32 *return_len)
+		    SilcUInt32 data_len, unsigned char *return_hash,
+		    SilcUInt32 *return_len)
 {
-  silc_hmac_make_internal(hmac, data, data_len, hmac->key, 
-			  hmac->key_len, return_hash);
-  if (return_len)
-    *return_len = hmac->hmac->len;
+  SILC_LOG_DEBUG(("Making HMAC for message"));
+
+  silc_hmac_init(hmac);
+  silc_hmac_update(hmac, data, data_len);
+  silc_hmac_final(hmac, return_hash, return_len);
 }
 
 /* Creates HMAC just as above except that this doesn't use the internal
    key. The key is sent as argument to the function. */
 
 void silc_hmac_make_with_key(SilcHmac hmac, unsigned char *data,
-			     uint32 data_len, 
-			     unsigned char *key, uint32 key_len,
+			     SilcUInt32 data_len,
+			     unsigned char *key, SilcUInt32 key_len,
 			     unsigned char *return_hash,
-			     uint32 *return_len)
+			     SilcUInt32 *return_len)
 {
-  silc_hmac_make_internal(hmac, data, data_len, key, key_len, return_hash);
-  if (return_len)
-    *return_len = hmac->hmac->len;
+  SILC_LOG_DEBUG(("Making HMAC for message"));
+
+  silc_hmac_init_with_key(hmac, key, key_len);
+  silc_hmac_update(hmac, data, data_len);
+  silc_hmac_final(hmac, return_hash, return_len);
 }
 
 /* Creates the HMAC just as above except that the hash value is truncated
    to the truncated_len sent as argument. NOTE: One should not truncate to
-   less than half of the length of original hash value. However, this 
+   less than half of the length of original hash value. However, this
    routine allows these dangerous truncations. */
 
 void silc_hmac_make_truncated(SilcHmac hmac, unsigned char *data,
-			      uint32 data_len,
-			      uint32 truncated_len,
+			      SilcUInt32 data_len,
+			      SilcUInt32 truncated_len,
 			      unsigned char *return_hash)
 {
-  unsigned char hvalue[hmac->hash->hash->hash_len];
+  unsigned char hvalue[SILC_HASH_MAXLEN];
+
+  SILC_LOG_DEBUG(("Making HMAC for message"));
 
-  silc_hmac_make_internal(hmac, data, data_len, 
-			  hmac->key, hmac->key_len, hvalue);
+  silc_hmac_init(hmac);
+  silc_hmac_update(hmac, data, data_len);
+  silc_hmac_final(hmac, return_hash, NULL);
   memcpy(return_hash, hvalue, truncated_len);
   memset(hvalue, 0, sizeof(hvalue));
 }
+
+/* Init HMAC for silc_hmac_update and silc_hmac_final. */
+
+void silc_hmac_init(SilcHmac hmac)
+{
+  silc_hmac_init_with_key(hmac, hmac->key, hmac->key_len);
+}
+
+/* Same as above but with specific key */
+
+void silc_hmac_init_with_key(SilcHmac hmac, const unsigned char *key,
+			     SilcUInt32 key_len)
+{
+  SilcHash hash = hmac->hash;
+  silc_hmac_init_internal(hmac, (unsigned char *)key, key_len);
+  silc_hash_init(hash);
+  silc_hash_update(hash, hmac->inner_pad, silc_hash_block_len(hash));
+}
+
+/* Add data to be used in the MAC computation. */
+
+void silc_hmac_update(SilcHmac hmac, const unsigned char *data,
+		      SilcUInt32 data_len)
+{
+  SilcHash hash = hmac->hash;
+  silc_hash_update(hash, data, data_len);
+}
+
+/* Compute the final MAC. */
+
+void silc_hmac_final(SilcHmac hmac, unsigned char *return_hash,
+		     SilcUInt32 *return_len)
+{
+  SilcHash hash = hmac->hash;
+  unsigned char mac[SILC_HASH_MAXLEN];
+
+  silc_hash_final(hash, mac);
+  silc_hash_init(hash);
+  silc_hash_update(hash, hmac->outer_pad, silc_hash_block_len(hash));
+  silc_hash_update(hash, mac, silc_hash_len(hash));
+  silc_hash_final(hash, mac);
+  memcpy(return_hash, mac, hmac->hmac->len);
+  memset(mac, 0, sizeof(mac));
+
+  if (return_len)
+    *return_len = hmac->hmac->len;
+}