!15 fix issue: "Current password:" is repeated twice when executing the passwd command as a normal user and the input password is wrong.
From: @panxh_purple Reviewed-by: @zhujianwei001 Signed-off-by: @zhujianwei001
This commit is contained in:
commit
1ac303200d
276
Move-check_user_in_passwd-from-pam_localuser.c-to-pa.patch
Normal file
276
Move-check_user_in_passwd-from-pam_localuser.c-to-pa.patch
Normal file
@ -0,0 +1,276 @@
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|
From c9593778a6133bf29eb2f47c24cc6d2f5d729fc8 Mon Sep 17 00:00:00 2001
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|
From: Fabrice Fontaine <fontaine.fabrice@gmail.com>
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Date: Thu, 11 Jun 2020 17:39:03 +0200
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Subject: [PATCH] Move check_user_in_passwd from pam_localuser.c to pam_modutil
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|
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|
Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
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* modules/pam_localuser/pam_localuser.c: Include
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<security/pam_modutil.h>.
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(pam_sm_authenticate): Replace check_user_in_passwd with
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pam_modutil_check_user_in_passwd.
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(check_user_in_passwd): Rename to pam_modutil_check_user_in_passwd,
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move to ...
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* libpam/pam_modutil_check_user.c: ... new file.
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* libpam/Makefile.am (libpam_la_SOURCES): Add pam_modutil_check_user.c.
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* libpam/include/security/pam_modutil.h
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(pam_modutil_check_user_in_passwd): New function declaration.
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* libpam/libpam.map (LIBPAM_MODUTIL_1.4.1): New interface.
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|
Co-authored-by: Dmitry V. Levin <ldv@altlinux.org>
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---
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|
libpam/Makefile.am | 1 +
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|
libpam/include/security/pam_modutil.h | 5 ++
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|
libpam/libpam.map | 5 ++
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|
libpam/pam_modutil_check_user.c | 90 +++++++++++++++++++++++++++++++++++
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|
modules/pam_localuser/pam_localuser.c | 86 +--------------------------------
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|
5 files changed, 103 insertions(+), 84 deletions(-)
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create mode 100644 libpam/pam_modutil_check_user.c
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|
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diff --git a/libpam/Makefile.am b/libpam/Makefile.am
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index 9252a83..11a1f32 100644
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--- a/libpam/Makefile.am
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+++ b/libpam/Makefile.am
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@@ -35,6 +35,7 @@ libpam_la_SOURCES = pam_account.c pam_auth.c pam_data.c pam_delay.c \
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pam_misc.c pam_password.c pam_prelude.c \
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pam_session.c pam_start.c pam_strerror.c \
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pam_vprompt.c pam_syslog.c pam_dynamic.c pam_audit.c \
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+ pam_modutil_check_user.c \
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pam_modutil_cleanup.c pam_modutil_getpwnam.c pam_modutil_ioloop.c \
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pam_modutil_getgrgid.c pam_modutil_getpwuid.c pam_modutil_getgrnam.c \
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pam_modutil_getspnam.c pam_modutil_getlogin.c pam_modutil_ingroup.c \
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diff --git a/libpam/include/security/pam_modutil.h b/libpam/include/security/pam_modutil.h
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index 3a6aec6..33f87b9 100644
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--- a/libpam/include/security/pam_modutil.h
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+++ b/libpam/include/security/pam_modutil.h
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@@ -58,6 +58,11 @@ extern "C" {
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#include <security/_pam_types.h>
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+extern int PAM_NONNULL((1,2))
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+pam_modutil_check_user_in_passwd(pam_handle_t *pamh,
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+ const char *user_name,
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+ const char *file_name);
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+
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extern struct passwd * PAM_NONNULL((1,2))
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pam_modutil_getpwnam(pam_handle_t *pamh, const char *user);
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diff --git a/libpam/libpam.map b/libpam/libpam.map
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|
index c9690a9..3cc7ef3 100644
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--- a/libpam/libpam.map
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+++ b/libpam/libpam.map
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@@ -82,3 +82,8 @@ LIBPAM_1.4 {
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|
global:
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pam_start_confdir;
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} LIBPAM_1.0;
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+
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+LIBPAM_MODUTIL_1.4.1 {
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+ global:
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+ pam_modutil_check_user_in_passwd;
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+} LIBPAM_MODUTIL_1.3.2;
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diff --git a/libpam/pam_modutil_check_user.c b/libpam/pam_modutil_check_user.c
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new file mode 100644
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index 0000000..898b13a
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--- /dev/null
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+++ b/libpam/pam_modutil_check_user.c
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@@ -0,0 +1,90 @@
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|
+#include "pam_modutil_private.h"
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|
+#include <security/pam_ext.h>
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|
+
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|
+#include <stdio.h>
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|
+#include <string.h>
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+#include <syslog.h>
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|
+
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|
+int
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|
+pam_modutil_check_user_in_passwd(pam_handle_t *pamh,
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+ const char *user_name,
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|
+ const char *file_name)
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|
+{
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|
+ int rc;
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+ size_t user_len;
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+ FILE *fp;
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|
+ char line[BUFSIZ];
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+
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+ /* Validate the user name. */
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+ if ((user_len = strlen(user_name)) == 0) {
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+ pam_syslog(pamh, LOG_NOTICE, "user name is not valid");
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+ return PAM_SERVICE_ERR;
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+ }
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|
+
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+ if (user_len > sizeof(line) - sizeof(":")) {
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+ pam_syslog(pamh, LOG_NOTICE, "user name is too long");
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+ return PAM_SERVICE_ERR;
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|
+ }
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+
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+ if (strchr(user_name, ':') != NULL) {
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+ /*
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+ * "root:x" is not a local user name even if the passwd file
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+ * contains a line starting with "root:x:".
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|
+ */
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+ return PAM_PERM_DENIED;
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+ }
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+
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+ /* Open the passwd file. */
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+ if (file_name == NULL) {
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|
+ file_name = "/etc/passwd";
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|
+ }
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|
+ if ((fp = fopen(file_name, "r")) == NULL) {
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|
+ pam_syslog(pamh, LOG_ERR, "error opening %s: %m", file_name);
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+ return PAM_SERVICE_ERR;
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|
+ }
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+
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+ /*
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|
+ * Scan the file using fgets() instead of fgetpwent_r() because
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|
+ * the latter is not flexible enough in handling long lines
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+ * in passwd files.
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|
+ */
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+ rc = PAM_PERM_DENIED;
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+ while (fgets(line, sizeof(line), fp) != NULL) {
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+ size_t line_len;
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|
+ const char *str;
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+
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+ /*
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+ * Does this line start with the user name
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+ * followed by a colon?
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+ */
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+ if (strncmp(user_name, line, user_len) == 0 &&
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+ line[user_len] == ':') {
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+ rc = PAM_SUCCESS;
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+ break;
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+ }
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+ /* Has a newline been read? */
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+ line_len = strlen(line);
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+ if (line_len < sizeof(line) - 1 ||
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+ line[line_len - 1] == '\n') {
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+ /* Yes, continue with the next line. */
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+ continue;
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+ }
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+
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+ /* No, read till the end of this line first. */
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+ while ((str = fgets(line, sizeof(line), fp)) != NULL) {
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+ line_len = strlen(line);
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+ if (line_len == 0 ||
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+ line[line_len - 1] == '\n') {
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+ break;
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+ }
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+ }
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+ if (str == NULL) {
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+ /* fgets returned NULL, we are done. */
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+ break;
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+ }
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+ /* Continue with the next line. */
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+ }
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+
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+ fclose(fp);
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+ return rc;
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+}
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diff --git a/modules/pam_localuser/pam_localuser.c b/modules/pam_localuser/pam_localuser.c
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index cb50752..a9f2233 100644
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--- a/modules/pam_localuser/pam_localuser.c
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+++ b/modules/pam_localuser/pam_localuser.c
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@@ -45,92 +45,10 @@
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#include <unistd.h>
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#include <security/pam_modules.h>
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+#include <security/pam_modutil.h>
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#include <security/pam_ext.h>
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#include "pam_inline.h"
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-static int
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-check_user_in_passwd(pam_handle_t *pamh, const char *user_name,
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- const char *file_name)
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-{
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- int rc;
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- size_t user_len;
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- FILE *fp;
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- char line[BUFSIZ];
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-
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|
- /* Validate the user name. */
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|
- if ((user_len = strlen(user_name)) == 0) {
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|
- pam_syslog(pamh, LOG_NOTICE, "user name is not valid");
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|
- return PAM_SERVICE_ERR;
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|
- }
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|
-
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|
- if (user_len > sizeof(line) - sizeof(":")) {
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|
- pam_syslog(pamh, LOG_NOTICE, "user name is too long");
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|
- return PAM_SERVICE_ERR;
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|
- }
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||||||
|
-
|
||||||
|
- if (strchr(user_name, ':') != NULL) {
|
||||||
|
- /*
|
||||||
|
- * "root:x" is not a local user name even if the passwd file
|
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|
- * contains a line starting with "root:x:".
|
||||||
|
- */
|
||||||
|
- return PAM_PERM_DENIED;
|
||||||
|
- }
|
||||||
|
-
|
||||||
|
- /* Open the passwd file. */
|
||||||
|
- if (file_name == NULL) {
|
||||||
|
- file_name = "/etc/passwd";
|
||||||
|
- }
|
||||||
|
- if ((fp = fopen(file_name, "r")) == NULL) {
|
||||||
|
- pam_syslog(pamh, LOG_ERR, "error opening %s: %m", file_name);
|
||||||
|
- return PAM_SERVICE_ERR;
|
||||||
|
- }
|
||||||
|
-
|
||||||
|
- /*
|
||||||
|
- * Scan the file using fgets() instead of fgetpwent_r() because
|
||||||
|
- * the latter is not flexible enough in handling long lines
|
||||||
|
- * in passwd files.
|
||||||
|
- */
|
||||||
|
- rc = PAM_PERM_DENIED;
|
||||||
|
- while (fgets(line, sizeof(line), fp) != NULL) {
|
||||||
|
- size_t line_len;
|
||||||
|
- const char *str;
|
||||||
|
-
|
||||||
|
- /*
|
||||||
|
- * Does this line start with the user name
|
||||||
|
- * followed by a colon?
|
||||||
|
- */
|
||||||
|
- if (strncmp(user_name, line, user_len) == 0 &&
|
||||||
|
- line[user_len] == ':') {
|
||||||
|
- rc = PAM_SUCCESS;
|
||||||
|
- break;
|
||||||
|
- }
|
||||||
|
- /* Has a newline been read? */
|
||||||
|
- line_len = strlen(line);
|
||||||
|
- if (line_len < sizeof(line) - 1 ||
|
||||||
|
- line[line_len - 1] == '\n') {
|
||||||
|
- /* Yes, continue with the next line. */
|
||||||
|
- continue;
|
||||||
|
- }
|
||||||
|
-
|
||||||
|
- /* No, read till the end of this line first. */
|
||||||
|
- while ((str = fgets(line, sizeof(line), fp)) != NULL) {
|
||||||
|
- line_len = strlen(line);
|
||||||
|
- if (line_len == 0 ||
|
||||||
|
- line[line_len - 1] == '\n') {
|
||||||
|
- break;
|
||||||
|
- }
|
||||||
|
- }
|
||||||
|
- if (str == NULL) {
|
||||||
|
- /* fgets returned NULL, we are done. */
|
||||||
|
- break;
|
||||||
|
- }
|
||||||
|
- /* Continue with the next line. */
|
||||||
|
- }
|
||||||
|
-
|
||||||
|
- fclose(fp);
|
||||||
|
- return rc;
|
||||||
|
-}
|
||||||
|
-
|
||||||
|
int
|
||||||
|
pam_sm_authenticate(pam_handle_t *pamh, int flags UNUSED,
|
||||||
|
int argc, const char **argv)
|
||||||
|
@@ -173,7 +91,7 @@ pam_sm_authenticate(pam_handle_t *pamh, int flags UNUSED,
|
||||||
|
return rc == PAM_CONV_AGAIN ? PAM_INCOMPLETE : rc;
|
||||||
|
}
|
||||||
|
|
||||||
|
- return check_user_in_passwd(pamh, user_name, file_name);
|
||||||
|
+ return pam_modutil_check_user_in_passwd(pamh, user_name, file_name);
|
||||||
|
}
|
||||||
|
|
||||||
|
int
|
||||||
|
--
|
||||||
|
1.8.3.1
|
||||||
|
|
||||||
10
pam.spec
10
pam.spec
@ -4,7 +4,7 @@
|
|||||||
%define _pamconfdir %{_sysconfdir}/pam.d
|
%define _pamconfdir %{_sysconfdir}/pam.d
|
||||||
Name: pam
|
Name: pam
|
||||||
Version: 1.4.0
|
Version: 1.4.0
|
||||||
Release: 1
|
Release: 2
|
||||||
Summary: Pluggable Authentication Modules for Linux
|
Summary: Pluggable Authentication Modules for Linux
|
||||||
License: BSD and GPLv2+
|
License: BSD and GPLv2+
|
||||||
URL: http://www.linux-pam.org/
|
URL: http://www.linux-pam.org/
|
||||||
@ -21,6 +21,9 @@ Source18: https://www.gnu.org/licenses/old-licenses/gpl-2.0.txt
|
|||||||
Patch0: bugfix-pam-1.1.8-faillock-failmessages.patch
|
Patch0: bugfix-pam-1.1.8-faillock-failmessages.patch
|
||||||
Patch1: bugfix-pam-1.1.8-faillock-systemtime.patch
|
Patch1: bugfix-pam-1.1.8-faillock-systemtime.patch
|
||||||
Patch2: fix-login-message.patch
|
Patch2: fix-login-message.patch
|
||||||
|
Patch3: Move-check_user_in_passwd-from-pam_localuser.c-to-pa.patch
|
||||||
|
Patch4: pam_faillock-fix-build-on-musl.patch
|
||||||
|
Patch5: pam_modutil_check_user_in_passwd-avoid-timing-attack.patch
|
||||||
|
|
||||||
BuildRequires: autoconf automake libtool bison flex sed cracklib-devel
|
BuildRequires: autoconf automake libtool bison flex sed cracklib-devel
|
||||||
BuildRequires: perl-interpreter pkgconfig gettext-devel libtirpc-devel libnsl2-devel
|
BuildRequires: perl-interpreter pkgconfig gettext-devel libtirpc-devel libnsl2-devel
|
||||||
@ -166,6 +169,11 @@ fi
|
|||||||
|
|
||||||
|
|
||||||
%changelog
|
%changelog
|
||||||
|
* Fri Sep 25 2020 panxiaohe <panxiaohe@huawei.com> - 1.4.0-2
|
||||||
|
- fix the following issue.
|
||||||
|
"Current password:" is repeated twice when executing the passwd
|
||||||
|
command as a normal user and the input password is wrong.
|
||||||
|
|
||||||
* Fri Jul 24 2020 Liquor <lirui130@huawei.com> - 1.4.0-1
|
* Fri Jul 24 2020 Liquor <lirui130@huawei.com> - 1.4.0-1
|
||||||
- update to 1.4.0
|
- update to 1.4.0
|
||||||
|
|
||||||
|
|||||||
76
pam_faillock-fix-build-on-musl.patch
Normal file
76
pam_faillock-fix-build-on-musl.patch
Normal file
@ -0,0 +1,76 @@
|
|||||||
|
From 0adbaeb273da1d45213134aa271e95987103281c Mon Sep 17 00:00:00 2001
|
||||||
|
From: Fabrice Fontaine <fontaine.fabrice@gmail.com>
|
||||||
|
Date: Thu, 11 Jun 2020 17:39:03 +0200
|
||||||
|
Subject: [PATCH] pam_faillock: fix build on musl
|
||||||
|
|
||||||
|
Use pam_modutil_check_user_in_passwd in pam_faillock.c instead of
|
||||||
|
fgetpwent_r which is not available on musl.
|
||||||
|
|
||||||
|
Resolves: https://github.com/linux-pam/linux-pam/issues/236
|
||||||
|
Resolves: https://github.com/linux-pam/linux-pam/pull/237
|
||||||
|
Fixes: http://autobuild.buildroot.org/results/0432736ffee376dd84757469434a4bbcfdcdaf4b
|
||||||
|
Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
|
||||||
|
---
|
||||||
|
modules/pam_faillock/pam_faillock.c | 39 +------------------------------------
|
||||||
|
1 file changed, 1 insertion(+), 38 deletions(-)
|
||||||
|
|
||||||
|
diff --git a/modules/pam_faillock/pam_faillock.c b/modules/pam_faillock/pam_faillock.c
|
||||||
|
index f592d0a..71988d0 100644
|
||||||
|
--- a/modules/pam_faillock/pam_faillock.c
|
||||||
|
+++ b/modules/pam_faillock/pam_faillock.c
|
||||||
|
@@ -71,8 +71,6 @@
|
||||||
|
#define MAX_TIME_INTERVAL 604800 /* 7 days */
|
||||||
|
#define FAILLOCK_CONF_MAX_LINELEN 1023
|
||||||
|
|
||||||
|
-#define PATH_PASSWD "/etc/passwd"
|
||||||
|
-
|
||||||
|
static const char default_faillock_conf[] = FAILLOCK_DEFAULT_CONF;
|
||||||
|
|
||||||
|
struct options {
|
||||||
|
@@ -348,42 +346,7 @@ set_conf_opt(pam_handle_t *pamh, struct options *opts, const char *name, const c
|
||||||
|
static int
|
||||||
|
check_local_user (pam_handle_t *pamh, const char *user)
|
||||||
|
{
|
||||||
|
- struct passwd pw, *pwp;
|
||||||
|
- char buf[16384];
|
||||||
|
- int found = 0;
|
||||||
|
- FILE *fp;
|
||||||
|
- int errn;
|
||||||
|
-
|
||||||
|
- fp = fopen(PATH_PASSWD, "r");
|
||||||
|
- if (fp == NULL) {
|
||||||
|
- pam_syslog(pamh, LOG_ERR, "unable to open %s: %m",
|
||||||
|
- PATH_PASSWD);
|
||||||
|
- return -1;
|
||||||
|
- }
|
||||||
|
-
|
||||||
|
- for (;;) {
|
||||||
|
- errn = fgetpwent_r(fp, &pw, buf, sizeof (buf), &pwp);
|
||||||
|
- if (errn == ERANGE) {
|
||||||
|
- pam_syslog(pamh, LOG_WARNING, "%s contains very long lines; corrupted?",
|
||||||
|
- PATH_PASSWD);
|
||||||
|
- break;
|
||||||
|
- }
|
||||||
|
- if (errn != 0)
|
||||||
|
- break;
|
||||||
|
- if (strcmp(pwp->pw_name, user) == 0) {
|
||||||
|
- found = 1;
|
||||||
|
- break;
|
||||||
|
- }
|
||||||
|
- }
|
||||||
|
-
|
||||||
|
- fclose (fp);
|
||||||
|
-
|
||||||
|
- if (errn != 0 && errn != ENOENT) {
|
||||||
|
- pam_syslog(pamh, LOG_ERR, "unable to enumerate local accounts: %m");
|
||||||
|
- return -1;
|
||||||
|
- } else {
|
||||||
|
- return found;
|
||||||
|
- }
|
||||||
|
+ return pam_modutil_check_user_in_passwd(pamh, user, NULL) == PAM_SUCCESS;
|
||||||
|
}
|
||||||
|
|
||||||
|
static int
|
||||||
|
--
|
||||||
|
1.8.3.1
|
||||||
|
|
||||||
30
pam_modutil_check_user_in_passwd-avoid-timing-attack.patch
Normal file
30
pam_modutil_check_user_in_passwd-avoid-timing-attack.patch
Normal file
@ -0,0 +1,30 @@
|
|||||||
|
From efd2a79c11982d0feebebbf740506c9555120b97 Mon Sep 17 00:00:00 2001
|
||||||
|
From: "Dmitry V. Levin" <ldv@altlinux.org>
|
||||||
|
Date: Tue, 16 Jun 2020 15:00:00 +0000
|
||||||
|
Subject: [PATCH] pam_modutil_check_user_in_passwd: avoid timing attacks
|
||||||
|
|
||||||
|
* libpam/pam_modutil_check_user.c (pam_modutil_check_user_in_passwd): Do
|
||||||
|
not exit the file reading loop when the user is found, continue reading
|
||||||
|
the file to avoid timing attacks.
|
||||||
|
---
|
||||||
|
libpam/pam_modutil_check_user.c | 4 +++-
|
||||||
|
1 file changed, 3 insertions(+), 1 deletion(-)
|
||||||
|
|
||||||
|
diff --git a/libpam/pam_modutil_check_user.c b/libpam/pam_modutil_check_user.c
|
||||||
|
index 898b13a..cf1bd1b 100644
|
||||||
|
--- a/libpam/pam_modutil_check_user.c
|
||||||
|
+++ b/libpam/pam_modutil_check_user.c
|
||||||
|
@@ -60,7 +60,9 @@ pam_modutil_check_user_in_passwd(pam_handle_t *pamh,
|
||||||
|
if (strncmp(user_name, line, user_len) == 0 &&
|
||||||
|
line[user_len] == ':') {
|
||||||
|
rc = PAM_SUCCESS;
|
||||||
|
- break;
|
||||||
|
+ /*
|
||||||
|
+ * Continue reading the file to avoid timing attacks.
|
||||||
|
+ */
|
||||||
|
}
|
||||||
|
/* Has a newline been read? */
|
||||||
|
line_len = strlen(line);
|
||||||
|
--
|
||||||
|
1.8.3.1
|
||||||
|
|
||||||
Loading…
x
Reference in New Issue
Block a user