Add proper per-file copyright notices/licenses and top-level license.

[bluesky.git] / bluesky / crypto.c

diff --git a/bluesky/crypto.c b/bluesky/crypto.c
index 89f6b12..492e4ff 100644 (file)
--- a/bluesky/crypto.c
+++ b/bluesky/crypto.c
@@ -3,7 +3,29 @@
  * Copyright (C) 2009  The Regents of the University of California
  * Written by Michael Vrable <mvrable@cs.ucsd.edu>
  *
- * TODO: Licensing
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
  */
 
 #include <stdint.h>
@@ -132,6 +154,9 @@ gboolean bluesky_crypt_block_needs_encryption(uint8_t type)
 void bluesky_crypt_block_encrypt(gchar *cloud_block, size_t len,
                                  BlueSkyCryptKeys *keys)
 {
+    if (bluesky_options.disable_crypto)
+        return;
+
     gcry_error_t status;
     gcry_cipher_hd_t handle;
 
@@ -177,7 +202,7 @@ void bluesky_crypt_block_encrypt(gchar *cloud_block, size_t len,
     }
 
     bluesky_crypt_hmac((char *)&header->crypt_iv,
-                       cloud_block + len - (char *)&header->crypt_iv,
+                       cloud_block + len - (char *)&header->crypt_iv - GUINT32_FROM_LE(header->size3),
                        keys->authentication_key,
                        header->crypt_auth);
 
@@ -185,7 +210,8 @@ void bluesky_crypt_block_encrypt(gchar *cloud_block, size_t len,
 }
 
 gboolean bluesky_crypt_block_decrypt(gchar *cloud_block, size_t len,
-                                     BlueSkyCryptKeys *keys)
+                                     BlueSkyCryptKeys *keys,
+                                     gboolean allow_unauth)
 {
     gcry_error_t status;
     uint8_t hmac_check[CRYPTO_HASH_SIZE];
@@ -200,17 +226,29 @@ gboolean bluesky_crypt_block_decrypt(gchar *cloud_block, size_t len,
         g_assert(memcmp(header->magic, CLOUDLOG_MAGIC_ENCRYPTED,
                         sizeof(header->magic)) == 0);
 
+    if (bluesky_options.disable_crypto) {
+        g_assert(encrypted == FALSE);
+        return TRUE;
+    }
+
     if (encrypted != bluesky_crypt_block_needs_encryption(header->type)) {
         g_warning("Encrypted status of item does not match expected!\n");
     }
 
     bluesky_crypt_hmac((char *)&header->crypt_iv,
-                       cloud_block + len - (char *)&header->crypt_iv,
+                       cloud_block + len - (char *)&header->crypt_iv - GUINT32_FROM_LE(header->size3),
                        keys->authentication_key,
                        hmac_check);
     if (memcmp(hmac_check, header->crypt_auth, CRYPTO_HASH_SIZE) != 0) {
-        g_warning("Cloud block HMAC does not match!\n");
-        return FALSE;
+        g_warning("Cloud block HMAC does not match!");
+        if (allow_unauth
+            && (header->type == LOGTYPE_INODE_MAP + '0'
+                || header->type == LOGTYPE_CHECKPOINT + '0'))
+        {
+            g_warning("Allowing unauthenticated data from cleaner");
+        } else {
+            return FALSE;
+        }
     }
 
     if (encrypted) {