Relevant BUGIDs: 440107

Purpose of commit: module reentrancy

Commit summary:
---------------
Commit sample code that uses getpwnam_r instead of getpwnam.  All code is
#ifdef'ed out right now.

2 files changed, 37 insertions, 1 deletions

diff --git a/CHANGELOG b/CHANGELOG
index 82a8fe38..11ccbe20 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -49,6 +49,8 @@ bug report - outstanding bugs are listed here:
 0.76: please submit patches for this section with actual code/doc
       patches!
 
+* pam_unix/support.c: sample use of reentrant NSS function.  Not yet active,
+  because modules do not include _pam_aconf_h! (Bug 440107 - vorlon)
 * doc/Makefile changes - use $(mandir) [courtesy Harald Welte] (Bug
   435760) and add some rules to make/delete the draft rfc I've been
   working on (Task 17426 - agmorgan)
diff --git a/modules/pam_unix/support.c b/modules/pam_unix/support.c
index 964d1a46..61915e57 100644
--- a/modules/pam_unix/support.c
+++ b/modules/pam_unix/support.c
@@ -314,6 +314,13 @@ int _unix_blankpasswd(unsigned int ctrl, const char *name)
 	struct spwd *spwdent = NULL;
 	char *salt = NULL;
 	int retval;
+#if HAVE_GETPWNAM_R
+	char *buf = NULL;
+	int bufsize = 0;
+	struct passwd pwd_buf;
+
+	pwd = &pwd_buf;
+#endif
 
 	D(("called"));
 
@@ -327,7 +334,25 @@ int _unix_blankpasswd(unsigned int ctrl, const char *name)
 		return 0;	/* will fail but don't let on yet */
 
 	/* UNIX passwords area */
-	pwd = getpwnam(name);	/* Get password file entry... */
+
+	/* Get password file entry... */
+#if HAVE_GETPWNAM_R
+	bufsize = 1024;
+	buf = malloc(bufsize);
+
+	if ((retval = getpwnam_r(name, pwd, buf, bufsize, &pwd))) {
+		pwd = NULL;
+	}
+	while (retval == ERANGE) {
+		bufsize += 1024;
+		buf = realloc(buf, bufsize);
+		if ((retval getpwnam_r(name, pwd, buf, bufsize, &pwd))) {
+			pwd = NULL;
+		}
+	}
+#else
+	pwd = getpwnam(name);
+#endif
 
 	if (pwd != NULL) {
 		if (strcmp( pwd->pw_passwd, "*NP*" ) == 0)
@@ -345,6 +370,10 @@ int _unix_blankpasswd(unsigned int ctrl, const char *name)
 					setreuid( 0, -1 );
 					if(setreuid( -1, pwd->pw_uid ) == -1)
 						/* Will fail elsewhere. */
+#if HAVE_GETPWNAM_R
+						if (buf)
+							free(buf);
+#endif
 						return 0;
 				}
 			}
@@ -384,6 +413,11 @@ int _unix_blankpasswd(unsigned int ctrl, const char *name)
 	if (salt)
 		_pam_delete(salt);
 
+#if HAVE_GETPWNAM_R
+	if (buf)
+		free(buf);
+#endif
+
 	return retval;
 }