[PATCH v2 2/4] chsh-chfn: Move pam auth to its own function, factoring out common code

Cody Maloney
2013-01-13T09:12:58Z

This makes it easier to add support for libuser, which needs the same PAM
authentication. Also removes duplicate code between chsh and chfn.

Signed-off-by: Cody Maloney <cmaloney@theoreticalchaos.com>
---
login-utils/Makemodule.am | 2 ++
login-utils/auth.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++
login-utils/auth.h | 13 +++++++++++++
login-utils/chfn.c | 33 +++------------------------------
login-utils/chsh.c | 33 +++------------------------------
5 files changed, 68 insertions(+), 60 deletions(-)
create mode 100644 login-utils/auth.c
create mode 100644 login-utils/auth.h

diff --git a/login-utils/Makemodule.am b/login-utils/Makemodule.am
index 479b87b..ee85329 100644
--- a/login-utils/Makemodule.am
+++ b/login-utils/Makemodule.am
@@ -62,6 +62,8 @@ dist_man_MANS += \
chfn_chsh_sources = \
login-utils/islocal.c \
login-utils/islocal.h \
+ login-utils/auth.c \
+ login-utils/auth.h \
login-utils/setpwnam.c \
login-utils/setpwnam.h
chfn_chsh_cflags = $(SUID_CFLAGS) $(AM_CFLAGS)
diff --git a/login-utils/auth.c b/login-utils/auth.c
new file mode 100644
index 0000000..373bd22
--- /dev/null
+++ b/login-utils/auth.c
@@ -0,0 +1,47 @@
+/*
+ * auth.c -- PAM authorization code, common between chsh and chfn
+ * (c) 2012 by Cody Maloney <cmaloney@theoreticalchaos.com>
+ *
+ * this program is free software. you can redistribute it and
+ * modify it under the terms of the gnu general public license.
+ * there is no warranty.
+ *
+ */
+
+#include "auth.h"
+
+#include "pamfail.h"
+
+int auth_pam(const char *service_name, uid_t uid, const char *username) {
+#ifdef REQUIRE_PASSWORD
+ if (uid != 0) {
+ pam_handle_t *pamh = NULL;
+ struct pam_conv conv = { misc_conv, NULL };
+ int retcode;
+
+ retcode = pam_start(service_name, username, &conv, &pamh);
+ if (pam_fail_check(pamh, retcode))
+ return FALSE;
+
+ retcode = pam_authenticate(pamh, 0);
+ if (pam_fail_check(pamh, retcode))
+ return FALSE;
+
+ retcode = pam_acct_mgmt(pamh, 0);
+ if (retcode == PAM_NEW_AUTHTOK_REQD)
+ retcode =
+ pam_chauthtok(pamh, PAM_CHANGE_EXPIRED_AUTHTOK);
+ if (pam_fail_check(pamh, retcode))
+ return FALSE;
+
+ retcode = pam_setcred(pamh, 0);
+ if (pam_fail_check(pamh, retcode))
+ return FALSE;
+
+ pam_end(pamh, 0);
+ /* no need to establish a session; this isn't a
+ * session-oriented activity... */
+ }
+ return TRUE;
+#endif /* REQUIRE_PASSWORD */
+}
diff --git a/login-utils/auth.h b/login-utils/auth.h
new file mode 100644
index 0000000..bf7c369
--- /dev/null
+++ b/login-utils/auth.h
@@ -0,0 +1,13 @@
+/*
+ * auth.h -- PAM authorization code, common between chsh and chfn
+ * (c) 2012 by Cody Maloney <cmaloney@theoreticalchaos.com>
+ *
+ * this program is free software. you can redistribute it and
+ * modify it under the terms of the gnu general public license.
+ * there is no warranty.
+ *
+ */
+
+#include <sys/types.h>
+
+extern int auth_pam(const char *service_name, uid_t uid, const char *username);
diff --git a/login-utils/chfn.c b/login-utils/chfn.c
index 76c0b03..e189558 100644
--- a/login-utils/chfn.c
+++ b/login-utils/chfn.c
@@ -31,12 +31,12 @@
#include <sys/types.h>
#include <unistd.h>

+#include "auth.h"
#include "c.h"
#include "env.h"
#include "closestream.h"
#include "islocal.h"
#include "nls.h"
-#include "pamfail.h"
#include "setpwnam.h"
#include "strutils.h"
#include "xalloc.h"
@@ -157,36 +157,9 @@ int main(int argc, char **argv)

printf(_("Changing finger information for %s.\n"), oldf.username);

-#ifdef REQUIRE_PASSWORD
- if (uid != 0) {
- pam_handle_t *pamh = NULL;
- struct pam_conv conv = { misc_conv, NULL };
- int retcode;
-
- retcode = pam_start("chfn", oldf.username, &conv, &pamh);
- if (pam_fail_check(pamh, retcode))
- return EXIT_FAILURE;
-
- retcode = pam_authenticate(pamh, 0);
- if (pam_fail_check(pamh, retcode))
- return EXIT_FAILURE;
-
- retcode = pam_acct_mgmt(pamh, 0);
- if (retcode == PAM_NEW_AUTHTOK_REQD)
- retcode =
- pam_chauthtok(pamh, PAM_CHANGE_EXPIRED_AUTHTOK);
- if (pam_fail_check(pamh, retcode))
- return EXIT_FAILURE;
-
- retcode = pam_setcred(pamh, 0);
- if (pam_fail_check(pamh, retcode))
- return EXIT_FAILURE;
-
- pam_end(pamh, 0);
- /* no need to establish a session; this isn't a
- * session-oriented activity... */
+ if(!auth_pam("chfn", uid, oldf.username)) {
+ return EXIT_FAILURE;
}
-#endif /* REQUIRE_PASSWORD */

if (interactive)
ask_info(&oldf, &newf);
diff --git a/login-utils/chsh.c b/login-utils/chsh.c
index 6e9325d..4113df5 100644
--- a/login-utils/chsh.c
+++ b/login-utils/chsh.c
@@ -32,12 +32,12 @@
#include <sys/types.h>
#include <unistd.h>

+#include "auth.h"
#include "c.h"
#include "env.h"
#include "closestream.h"
#include "islocal.h"
#include "nls.h"
-#include "pamfail.h"
#include "pathnames.h"
#include "setpwnam.h"
#include "xalloc.h"
@@ -147,36 +147,9 @@ int main(int argc, char **argv)

printf(_("Changing shell for %s.\n"), pw->pw_name);

-#ifdef REQUIRE_PASSWORD
- if (uid != 0) {
- pam_handle_t *pamh = NULL;
- struct pam_conv conv = { misc_conv, NULL };
- int retcode;
-
- retcode = pam_start("chsh", pw->pw_name, &conv, &pamh);
- if (pam_fail_check(pamh, retcode))
- return EXIT_FAILURE;
-
- retcode = pam_authenticate(pamh, 0);
- if (pam_fail_check(pamh, retcode))
- return EXIT_FAILURE;
-
- retcode = pam_acct_mgmt(pamh, 0);
- if (retcode == PAM_NEW_AUTHTOK_REQD)
- retcode =
- pam_chauthtok(pamh, PAM_CHANGE_EXPIRED_AUTHTOK);
- if (pam_fail_check(pamh, retcode))
- return EXIT_FAILURE;
-
- retcode = pam_setcred(pamh, 0);
- if (pam_fail_check(pamh, retcode))
- return EXIT_FAILURE;
-
- pam_end(pamh, 0);
- /* no need to establish a session; this isn't a
- * session-oriented activity... */
+ if(!auth_pam("chsh", uid, pw->pw_name)) {
+ return EXIT_FAILURE;
}
-#endif /* REQUIRE_PASSWORD */

if (!shell) {
shell = prompt(_("New shell"), oldshell);
--
1.8.1