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-rw-r--r--shadow/shadow.h16
1 files changed, 10 insertions, 6 deletions
diff --git a/shadow/shadow.h b/shadow/shadow.h
index 6f3a570e4b..351882e448 100644
--- a/shadow/shadow.h
+++ b/shadow/shadow.h
@@ -15,7 +15,11 @@
    License along with the GNU C Library; if not, see
    <http://www.gnu.org/licenses/>.  */
 
-/* Declaration of types and functions for shadow password suite.  */
+/* Declaration of types and functions for "shadow" storage of hashed
+   passphrases.  The shadow database is like the user database, but is
+   only accessible with special privileges, so that malicious users
+   cannot retrieve everyone else's hashed passphrase to brute-force at
+   their convenience.  */
 
 #ifndef _SHADOW_H
 #define _SHADOW_H	1
@@ -35,11 +39,11 @@
 
 __BEGIN_DECLS
 
-/* Structure of the password file.  */
+/* A record in the shadow database.  */
 struct spwd
   {
     char *sp_namp;		/* Login name.  */
-    char *sp_pwdp;		/* Encrypted password.  */
+    char *sp_pwdp;		/* Hashed passphrase.  */
     long int sp_lstchg;		/* Date of last change.  */
     long int sp_min;		/* Minimum number of days between changes.  */
     long int sp_max;		/* Maximum number of days between changes.  */
@@ -101,7 +105,7 @@ extern struct spwd *sgetspent (const char *__string);
    therefore not marked with __THROW.  */
 extern struct spwd *fgetspent (FILE *__stream);
 
-/* Write line containing shadow password entry to stream.
+/* Write line containing shadow entry to stream.
 
    This function is not part of POSIX and therefore no official
    cancellation point.  But due to similarity with an POSIX interface
@@ -137,10 +141,10 @@ extern int fgetspent_r (FILE *__stream, struct spwd *__result_buf,
 /* The simple locking functionality provided here is not suitable for
    multi-threaded applications.  */
 
-/* Protect password file against multi writers.  */
+/* Request exclusive access to /etc/passwd and /etc/shadow.  */
 extern int lckpwdf (void) __THROW;
 
-/* Unlock password file.  */
+/* Release exclusive access to /etc/passwd and /etc/shadow.  */
 extern int ulckpwdf (void) __THROW;
 
 __END_DECLS