Add aacs_decrypt_bus()

Required for BD+ when bus encryption is used.

ChangeLog

+- Add aacs_decrypt_bus().
 - Add aacs_get_bdj_root_cert_hash().
 - Add aacs_get_content_cert_id().
 - Verify content certificate signature.

src/libaacs/aacs.c

@@ -1228,6 +1228,15 @@ static void _decrypt_unit_bus(AACS *aacs, uint8_t *buf)
     }
 }
 
+int aacs_decrypt_bus(AACS *aacs, uint8_t *buf)
+{
+    if (buf[0] & 0xc0) {
+        _decrypt_unit_bus(aacs, buf);
+    }
+
+    return 1;
+}
+
 int aacs_decrypt_unit(AACS *aacs, uint8_t *buf)
 {
     unsigned int i;

src/libaacs/aacs.h

@@ -51,6 +51,7 @@ AACS_PUBLIC AACS *aacs_open2(const char *path, const char *keyfile_path, int *er
 AACS_PUBLIC void aacs_close(AACS *aacs);
 AACS_PUBLIC void aacs_select_title(AACS *aacs, uint32_t title); /* 0 - top menu, 0xffff - first play */
 AACS_PUBLIC int  aacs_decrypt_unit(AACS *aacs, uint8_t *buf);
+AACS_PUBLIC int  aacs_decrypt_bus(AACS *aacs, uint8_t *buf);
 
 /* Disc information */
 AACS_PUBLIC int aacs_get_mkb_version(AACS *aacs);