1 files changed, 58 insertions, 0 deletions
diff --git a/bcache-key.c b/bcache-key.c
new file mode 100644
index 0000000..53dbe37
--- /dev/null
+++ b/bcache-key.c
@@ -0,0 +1,58 @@
+#include <errno.h>
+#include <unistd.h>
+#include <keyutils.h>
+#include <uuid/uuid.h>
+#include <nih/command.h>
+#include <nih/option.h>
+
+#include "bcache.h"
+#include "libbcache.h"
+#include "crypto.h"
+
+NihOption opts_unlock[] = {
+	NIH_OPTION_LAST
+};
+
+int cmd_unlock(NihCommand *command, char * const *args)
+{
+	struct bcache_disk_key disk_key;
+	struct bcache_key key;
+	struct cache_sb sb;
+	char *passphrase;
+	char uuid[40];
+	char description[60];
+
+	if (!args[0] || args[1])
+		die("please supply a single device");
+
+	bcache_super_read(args[0], &sb);
+
+	if (!CACHE_SET_ENCRYPTION_KEY(&sb))
+		die("filesystem is not encrypted");
+
+	memcpy(&disk_key, sb.encryption_key, sizeof(disk_key));
+
+	if (!memcmp(&disk_key, bch_key_header, sizeof(bch_key_header)))
+		die("filesystem does not have encryption key");
+
+	passphrase = read_passphrase("Enter passphrase: ");
+
+	derive_passphrase(&key, passphrase);
+	disk_key_encrypt(&disk_key, &key);
+
+	if (memcmp(&disk_key, bch_key_header, sizeof(bch_key_header)))
+		die("incorrect passphrase");
+
+	uuid_unparse_lower(sb.user_uuid.b, uuid);
+	sprintf(description, "bcache:%s", uuid);
+
+	if (add_key("logon", description, &key, sizeof(key),
+		    KEY_SPEC_USER_KEYRING) < 0)
+		die("add_key error: %s", strerror(errno));
+
+	memzero_explicit(&disk_key, sizeof(disk_key));
+	memzero_explicit(&key, sizeof(key));
+	memzero_explicit(passphrase, strlen(passphrase));
+	free(passphrase);
+	return 0;
+}