lib/crypt: Add helpers for operating on /etc/shadow

Provides helper functions for reading, writing, and checking against
/etc/shadow. The main use case if for authenticating clients against the
"system" password, which is set as the root password.

Signed-off-by: Samuel Mendoza-Jonas <sam@mendozajonas.com>

1 files changed, 49 insertions, 0 deletions

diff --git a/lib/crypt/crypt.h b/lib/crypt/crypt.h
new file mode 100644
index 0000000..4b242f0
--- /dev/null
+++ b/lib/crypt/crypt.h
@@ -0,0 +1,49 @@
+/*
+ *  Copyright (C) 2018 IBM Corporation
+ *
+ *  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; 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
+ *  GNU General Public License for more details.
+ *
+ */
+#ifndef CRYPT_H
+#define CRYPT_H
+
+#include "config.h"
+
+#ifdef CRYPT_SUPPORT
+
+char *crypt_get_hash(void *ctx);
+bool crypt_check_password(const char *password);
+int crypt_set_password(void *ctx, const char *password);
+int crypt_set_password_hash(void *ctx, const char *hash);
+
+#else
+
+static inline char *crypt_get_hash(void *ctx __attribute__((unused)))
+{
+	return NULL;
+}
+static inline bool crypt_check_password(
+		const char *password __attribute__((unused)))
+{
+	return false;
+}
+static inline int crypt_set_password(void *ctx __attribute__((unused)),
+		const char *password __attribute__((unused)))
+{
+	return -1;
+}
+static inline int crypt_set_password_hash(void *ctx __attribute__((unused)),
+		const char *hash __attribute__((unused)))
+{
+	return -1;
+}
+
+#endif
+#endif /* CRYPT_H */