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+++ LICENSE-slock
@@ -0,0 +1,24 @@
+MIT/X Consortium License
+
+© 2015-2016 Markus Teich <markus.teich@stusta.mhn.de>
+© 2014 Dimitris Papastamos <sin@2f30.org>
+© 2006-2014 Anselm R Garbe <anselm@garbe.us>
+© 2014-2016 Laslo Hunhold <dev@frign.de>
+
+Permission is hereby granted, free of charge, to any person obtaining a
+copy of this software and associated documentation files (the "Software"),
+to deal in the Software without restriction, including without limitation
+the rights to use, copy, modify, merge, publish, distribute, sublicense,
+and/or sell copies of the Software, and to permit persons to whom the
+Software is furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+DEALINGS IN THE SOFTWARE.
+++ Makefile
@@ -20,9 +20,9 @@
LIBS += -lev
LIBS += -lm
-# OpenBSD lacks PAM, use bsd_auth(3) instead.
+# On OpenBSD we use bsd_auth(3) instead.
ifneq ($(UNAME),OpenBSD)
- LIBS += -lpam
+ LIBS += -lcrypt
endif
FILES:=$(wildcard *.c)
@@ -50,9 +50,7 @@
install: all
$(INSTALL) -d $(DESTDIR)$(PREFIX)/bin
- $(INSTALL) -d $(DESTDIR)$(SYSCONFDIR)/pam.d
$(INSTALL) -m 755 i3lock $(DESTDIR)$(PREFIX)/bin/i3lock
- $(INSTALL) -m 644 i3lock.pam $(DESTDIR)$(SYSCONFDIR)/pam.d/i3lock
uninstall:
rm -f $(DESTDIR)$(PREFIX)/bin/i3lock
@@ -61,7 +59,7 @@
[ ! -d i3lock-${VERSION} ] || rm -rf i3lock-${VERSION}
[ ! -e i3lock-${VERSION}.tar.bz2 ] || rm i3lock-${VERSION}.tar.bz2
mkdir i3lock-${VERSION}
- cp *.c *.h i3lock.1 i3lock.pam Makefile LICENSE README.md CHANGELOG i3lock-${VERSION}
+ cp *.c *.h i3lock.1 Makefile LICENSE README.md CHANGELOG i3lock-${VERSION}
sed -e 's/^I3LOCK_VERSION:=\(.*\)/I3LOCK_VERSION:=$(shell /bin/echo '${I3LOCK_VERSION}' | sed 's/\\/\\\\/g')/g;s/^VERSION:=\(.*\)/VERSION:=${VERSION}/g' Makefile > i3lock-${VERSION}/Makefile
tar cfj i3lock-${VERSION}.tar.bz2 i3lock-${VERSION}
rm -rf i3lock-${VERSION}
+++ i3lock.1
@@ -43,8 +43,6 @@
You can specify either a background color or a PNG image which will be displayed while your screen is locked.
.IP \[bu]
You can specify whether i3lock should bell upon a wrong password.
-.IP \[bu]
-i3lock uses PAM and therefore is compatible with LDAP, etc.
.SH OPTIONS
@@ -66,8 +64,7 @@
.B \-u, \-\-no-unlock-indicator
Disable the unlock indicator. i3lock will by default show an unlock indicator
after pressing keys. This will give feedback for every keypress and it will
-show you the current PAM state (whether your password is currently being
-verified or whether it is wrong).
+show you whether your password is currently being verified or whether it is wrong.
.TP
.BI \-i\ path \fR,\ \fB\-\-image= path
@@ -95,7 +92,7 @@
.TP
.B \-e, \-\-ignore-empty-password
When an empty password is provided by the user, do not validate
-it. Without this option, the empty password will be provided to PAM
+it. Without this option, the empty password will be validated
and, if invalid, the user will have to wait a few seconds before
another try. This can be useful if the XF86ScreenSaver key is used to
put a laptop to sleep and bounce on resume or if you happen to wake up
+++ i3lock.c
@@ -21,7 +21,9 @@
#ifdef __OpenBSD__
#include <bsd_auth.h>
#else
-#include <security/pam_appl.h>
+#include <shadow.h>
+#include <grp.h>
+#include <errno.h>
#endif
#include <getopt.h>
#include <string.h>
@@ -57,7 +59,7 @@
xcb_window_t win;
static xcb_cursor_t cursor;
#ifndef __OpenBSD__
-static pam_handle_t *pam_handle;
+const char *hash = NULL;
#endif
int input_position = 0;
/* Holds the password you enter (in UTF-8). */
@@ -90,6 +92,37 @@
bool ignore_empty_password = false;
bool skip_repeated_empty_password = false;
+/*
+ * Shamelessly stolen from slock. See LICENSE-slock.
+ * This adjusts the process' out of memory score,
+ * so it isn't killed by the kernel under any circumstances.
+ */
+#ifdef __linux__
+#include <fcntl.h>
+#include <linux/oom.h>
+
+static void
+dontkillme(void)
+{
+ FILE *f;
+ const char oomfile[] = "/proc/self/oom_score_adj";
+
+ if (!(f = fopen(oomfile, "w"))) {
+ if (errno == ENOENT)
+ return;
+ errx(EXIT_FAILURE, "i3lock: fopen %s: %s", oomfile, strerror(errno));
+ }
+ fprintf(f, "%d", OOM_SCORE_ADJ_MIN);
+ if (fclose(f)) {
+ if (errno == EACCES)
+ errx(EXIT_FAILURE, "i3lock: unable to disable OOM killer. "
+ "Make sure to suid or sgid i3lock.");
+ else
+ errx(EXIT_FAILURE, "i3lock: fclose %s: %s", oomfile, strerror(errno));
+ }
+}
+#endif
+
/* isutf, u8_dec © 2005 Jeff Bezanson, public domain */
#define isutf(c) (((c)&0xC0) != 0x80)
@@ -281,16 +314,16 @@
exit(0);
}
#else
- if (pam_authenticate(pam_handle, 0) == PAM_SUCCESS) {
- DEBUG("successfully authenticated\n");
- clear_password_memory();
+ /*
+ * Shamelessly stolen from slock. See LICENSE-slock.
+ */
+ char *inputhash;
- /* PAM credentials should be refreshed, this will for example update any kerberos tickets.
- * Related to credentials pam_end() needs to be called to cleanup any temporary
- * credentials like kerberos /tmp/krb5cc_pam_* files which may of been left behind if the
- * refresh of the credentials failed. */
- pam_setcred(pam_handle, PAM_REFRESH_CRED);
- pam_end(pam_handle, PAM_SUCCESS);
+ if (!(inputhash = crypt(password, hash)))
+ fprintf(stderr, "i3lock: crypt: %s", strerror(errno));
+ else if (!strcmp(inputhash, hash)) {
+ DEBUG("successfully authenticated");
+ clear_password_memory();
exit(0);
}
@@ -626,39 +659,6 @@
redraw_screen();
}
-#ifndef __OpenBSD__
-/*
- * Callback function for PAM. We only react on password request callbacks.
- *
- */
-static int conv_callback(int num_msg, const struct pam_message **msg,
- struct pam_response **resp, void *appdata_ptr) {
- if (num_msg == 0)
- return 1;
-
- /* PAM expects an array of responses, one for each message */
- if ((*resp = calloc(num_msg, sizeof(struct pam_response))) == NULL) {
- perror("calloc");
- return 1;
- }
-
- for (int c = 0; c < num_msg; c++) {
- if (msg[c]->msg_style != PAM_PROMPT_ECHO_OFF &&
- msg[c]->msg_style != PAM_PROMPT_ECHO_ON)
- continue;
-
- /* return code is currently not used but should be set to zero */
- resp[c]->resp_retcode = 0;
- if ((resp[c]->resp = strdup(password)) == NULL) {
- perror("strdup");
- return 1;
- }
- }
-
- return 0;
-}
-#endif
-
/*
* This callback is only a dummy, see xcb_prepare_cb and xcb_check_cb.
* See also man libev(3): "ev_prepare" and "ev_check" - customise your event loop
@@ -813,10 +813,6 @@
struct passwd *pw;
char *username;
char *image_path = NULL;
-#ifndef __OpenBSD__
- int ret;
- struct pam_conv conv = {conv_callback, NULL};
-#endif
int curs_choice = CURS_NONE;
int o;
int optind = 0;
@@ -842,6 +838,48 @@
if ((username = pw->pw_name) == NULL)
errx(EXIT_FAILURE, "pw->pw_name is NULL.\n");
+#ifndef __OpenBSD__
+ /*
+ * Shamelessly stolen from slock. See LICENSE-slock.
+ *
+ * Slock has code to make it run as nobody:nogroup, which has the added
+ * security that the locker can only be killed by root.
+ * It causes problems with the xcb_connect in raise_loop, however,
+ * and I'm not aware of any other methods to keep the calling user from
+ * killing the locker.
+ * This means that a malicious program running as your user
+ * could easily bypass your locker by killing it.
+ * However, if such a program even manages to be running, you're pretty
+ * screwed regardless.
+ */
+
+#ifdef __linux__
+ dontkillme();
+#endif
+
+ hash = pw->pw_passwd;
+
+ if (!strcmp(hash, "x")) {
+ struct spwd *sp;
+ if (!(sp = getspnam(pw->pw_name)))
+ errx(EXIT_FAILURE, "i3lock: getspnam: cannot retrieve shadow entry. "
+ "Make sure to suid or sgid i3lock.");
+ hash = sp->sp_pwdp;
+ }
+
+ errno = 0;
+ if (!crypt("", hash))
+ errx(EXIT_FAILURE, "i3lock: crypt: %s", strerror(errno));
+
+ /* drop privileges */
+ if (setgroups(0, NULL) < 0)
+ errx(EXIT_FAILURE, "i3lock: setgroups: %s", strerror(errno));
+ if (setgid(pw->pw_gid) < 0)
+ errx(EXIT_FAILURE, "i3lock: setgid: %s", strerror(errno));
+ if (setuid(pw->pw_uid) < 0)
+ errx(EXIT_FAILURE, "i3lock: setuid: %s", strerror(errno));
+#endif
+
char *optstring = "hvnbdc:p:ui:teI:f";
while ((o = getopt_long(argc, argv, optstring, longopts, &optind)) != -1) {
switch (o) {
@@ -910,15 +948,6 @@
* the unlock indicator upon keypresses. */
srand(time(NULL));
-#ifndef __OpenBSD__
- /* Initialize PAM */
- if ((ret = pam_start("i3lock", username, &conv, &pam_handle)) != PAM_SUCCESS)
- errx(EXIT_FAILURE, "PAM: %s", pam_strerror(pam_handle, ret));
-
- if ((ret = pam_set_item(pam_handle, PAM_TTY, getenv("DISPLAY"))) != PAM_SUCCESS)
- errx(EXIT_FAILURE, "PAM: %s", pam_strerror(pam_handle, ret));
-#endif
-
/* Using mlock() as non-super-user seems only possible in Linux.
* Users of other operating systems should use encrypted swap/no swap
* (or remove the ifdef and run i3lock as super-user).
+++ i3lock.pam
@@ -1,6 +0,0 @@
-#
-# PAM configuration file for the i3lock screen locker. By default, it includes
-# the 'login' configuration file (see /etc/pam.d/login)
-#
-
-auth include login
|