From: Lennart Poettering <lennart@poettering.net>
Date: Wed, 13 Nov 2019 22:28:05 +0000 (+0100)
Subject: libcrypt-util: add superficial validator for UNIX hashed password strings
X-Git-Tag: v245-rc1~116^2~26
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=64aa2622a3baea1f62732f136230543c9d669cd1;p=thirdparty%2Fsystemd.git

libcrypt-util: add superficial validator for UNIX hashed password strings
---

diff --git a/src/shared/libcrypt-util.c b/src/shared/libcrypt-util.c
index b1a81680305..f41685ae450 100644
--- a/src/shared/libcrypt-util.c
+++ b/src/shared/libcrypt-util.c
@@ -73,3 +73,14 @@ int make_salt(char **ret) {
         return 0;
 #endif
 }
+
+bool hashed_password_valid(const char *s) {
+
+        /* Returns true if the specified string is a 'valid' hashed UNIX password, i.e. if starts with '$' or
+         * with '!$' (the latter being a valid, yet locked password). */
+
+        if (isempty(s))
+                return false;
+
+        return STARTSWITH_SET(s, "$", "!$");
+}
diff --git a/src/shared/libcrypt-util.h b/src/shared/libcrypt-util.h
index 3da1ab5ad98..93f0e13ffbe 100644
--- a/src/shared/libcrypt-util.h
+++ b/src/shared/libcrypt-util.h
@@ -18,3 +18,5 @@
 #include <stdlib.h>
 
 int make_salt(char **ret);
+
+bool hashed_password_valid(const char *s);