sulogin: agetty: use the plymouth local protocol instead the plymouth binary

for stopping plymouthd.  That do not depend on the existence of
the plymouth binary if it e.g. becomes uninstalled or an other
service is providing plymouthd facilities.

[kzak@redhat.com: - fix compiler warnings [-Wpointer-sign]
                  - use sizeof() for write_all()
                  - cast to char* for read_all]

Signed-off-by: Werner Fink <werner@suse.de>
Signed-off-by: Karel Zak <kzak@redhat.com>

5 files changed, 223 insertions, 82 deletions

diff --git a/include/plymouth-ctrl.h b/include/plymouth-ctrl.h
new file mode 100644
index 000000000..e1df363eb
--- /dev/null
+++ b/include/plymouth-ctrl.h
@@ -0,0 +1,65 @@
+/*
+ * plymouth-ctrl.h	Header file for communcations with plymouthd
+ *
+ * Copyright (c) 2016 SUSE Linux GmbH, All rights reserved.
+ * Copyright (c) 2016 Werner Fink <werner@suse.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *  
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program (see the file COPYING); if not, write to the
+ * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
+ * MA 02110-1301, USA.
+ *
+ * Author: Werner Fink <werner@suse.de>
+ */
+
+/*
+ * Taken from plymouth 0.9.0 src/ply-boot-protocol.h
+ */
+
+#ifndef UTIL_LINUX_PLYMOUTH_CTRL_H
+#define UTIL_LINUX_PLYMOUTH_CTRL_H
+
+#define PLYMOUTH_SOCKET_PATH	"\0/org/freedesktop/plymouthd"
+#define ANSWER_TYP		'\x2'
+#define ANSWER_ENQ		'\x5'
+#define ANSWER_ACK		'\x6'
+#define ANSWER_MLT		'\t'
+#define ANSWER_NCK		'\x15'
+
+#define MAGIC_PRG_STOP		'A'
+#define MAGIC_PRG_CONT		'a'
+#define MAGIC_UPDATE		'U'
+#define MAGIC_SYS_UPDATE	'u'
+#define MAGIC_SYS_INIT		'S'
+#define MAGIC_DEACTIVATE	'D'
+#define MAGIC_REACTIVATE	'r'
+#define MAGIC_SHOW_SPLASH	'$'
+#define MAGIC_HIDE_SPLASH	'H'
+#define MAGIC_CHMOD		'C'
+#define MAGIC_CHROOT		'R'
+#define MAGIC_ACTIVE_VT		'V'
+#define MAGIC_QUESTION		'W'
+#define MAGIC_SHOW_MSG		'M'
+#define MAGIC_HIDE_MSG		'm'
+#define MAGIC_KEYSTROKE		'K'
+#define MAGIC_KEYSTROKE_RM	'L'
+#define MAGIC_PING		'P'
+#define MAGIC_QUIT		'Q'
+#define MAGIC_CACHED_PWD	'c'
+#define MAGIC_ASK_PWD		'*'
+#define MAGIC_DETAILS		'!'
+
+#define PLYMOUTH_TERMIOS_FLAGS_DELAY	30
+extern int plymouth_command(int cmd, ...);
+
+#endif /* UTIL_LINUX_PLYMOUTH_CTRL_H */
diff --git a/lib/Makemodule.am b/lib/Makemodule.am
index 092d54e74..b2172db13 100644
--- a/lib/Makemodule.am
+++ b/lib/Makemodule.am
@@ -16,6 +16,7 @@ libcommon_la_SOURCES = \
 	lib/md5.c \
 	lib/pager.c \
 	lib/path.c \
+	lib/plymouth-ctrl.c \
 	lib/randutils.c \
 	lib/setproctitle.c \
 	lib/strutils.c \
diff --git a/lib/plymouth-ctrl.c b/lib/plymouth-ctrl.c
new file mode 100644
index 000000000..2a1b2ce3e
--- /dev/null
+++ b/lib/plymouth-ctrl.c
@@ -0,0 +1,147 @@
+/*
+ * plymouth-ctrl.c	Simply communcations with plymouthd
+ *			to avoid forked sub processes and/or
+ *			misssed plymouth send commands tool
+ *			due a plymouthd replacment.
+ *
+ * Copyright (c) 2016 SUSE Linux GmbH, All rights reserved.
+ * Copyright (c) 2016 Werner Fink <werner@suse.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program (see the file COPYING); if not, write to the
+ * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
+ * MA 02110-1301, USA.
+ *
+ * Author: Werner Fink <werner@suse.de>
+ */
+
+#include <errno.h>
+#include <limits.h>
+#include <poll.h>
+#include <signal.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <sys/mman.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <sys/un.h>
+#include <unistd.h>
+
+#include "all-io.h"
+#include "c.h"
+#include "nls.h"
+#include "plymouth-ctrl.h"
+
+static int can_read(int fd, const long timeout)
+{
+	struct pollfd fds = {
+		.fd = fd,
+		.events = POLLIN|POLLPRI,
+		.revents = 0,
+	};
+	int ret;
+
+	do {
+		ret = poll(&fds, 1, timeout);
+	} while ((ret < 0) && (errno == EINTR));
+
+	return (ret == 1) && (fds.revents & (POLLIN|POLLPRI));
+}
+
+static int open_un_socket_and_connect(void)
+{
+	struct sockaddr_un su = {		/* The abstract UNIX socket of plymouth */
+		.sun_family = AF_UNIX,
+		.sun_path = PLYMOUTH_SOCKET_PATH,
+	};
+	const int one = 1;
+	int fd, ret;
+
+	fd = socket(PF_UNIX, SOCK_STREAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
+	if (fd < 0) {
+		warnx(_("can not open UNIX socket"));
+		goto err;
+	}
+
+	ret = setsockopt(fd, SOL_SOCKET, SO_PASSCRED, &one, (socklen_t)sizeof(one));
+	if (ret < 0) {
+		warnx(_("can not set option for UNIX socket"));
+		close(fd);
+		fd = -1;
+		goto err;
+	}
+
+	/*
+	 * Please note that the PLYMOUTH_SOCKET_PATH has a
+	 * leading NULL byte to mark it as an abstract socket
+	 */
+	ret = connect(fd, &su, offsetof(struct sockaddr_un, sun_path) + 1 + strlen(su.sun_path+1));
+	if (ret < 0) {
+		if (errno != ECONNREFUSED)
+			warnx(_("can not connect on UNIX socket"));
+		close(fd);
+		fd = -1;
+		goto err;
+	}
+err:
+	return fd;
+}
+
+int plymouth_command(int cmd, ...)
+{
+	uint8_t answer[2], command[2];
+	struct sigaction sp, op;
+	int fdsock = -1, ret = 0;
+
+	sigemptyset (&sp.sa_mask);
+	sp.sa_handler = SIG_IGN;
+	sp.sa_flags = SA_RESTART;
+	sigaction(SIGPIPE, &sp, &op);
+
+	/*
+	 * The plymouthd does read at least two bytes.
+	 */
+	command[1] = '\0';
+	switch (cmd) {
+	case MAGIC_PING:
+		fdsock = open_un_socket_and_connect();
+		if (fdsock >= 0) {
+			command[0] = cmd;
+			write_all(fdsock, command, sizeof(command));
+		}
+		break;
+	case MAGIC_QUIT:
+		fdsock = open_un_socket_and_connect();
+		if (fdsock >= 0) {
+			command[0] = cmd;
+			write_all(fdsock, command, sizeof(command));
+		}
+		break;
+	default:
+		warnx(_("the plymouth request %c is not implemented"), cmd);
+	case '?':
+		goto err;
+	}
+
+	answer[0] = '\0';
+	if (fdsock >= 0) {
+		if (can_read(fdsock, 1000))
+			read_all(fdsock, (char *) &answer[0], sizeof(answer));
+		close(fdsock);
+	}
+	sigaction(SIGPIPE, &op, NULL);
+	ret = (answer[0] == ANSWER_ACK) ? 1 : 0;
+err:
+	return ret;
+}
+
diff --git a/login-utils/sulogin.c b/login-utils/sulogin.c
index 601d38caf..8d6e65229 100644
--- a/login-utils/sulogin.c
+++ b/login-utils/sulogin.c
@@ -58,6 +58,7 @@
 #include "closestream.h"
 #include "nls.h"
 #include "pathnames.h"
+#include "plymouth-ctrl.h"
 #include "strutils.h"
 #include "ttyutils.h"
 #include "sulogin-consoles.h"
@@ -92,42 +93,6 @@ static int locked_account_password(const char *passwd)
 	return 0;
 }
 
-#ifdef TIOCGLCKTRMIOS
-/*
- * For the case plymouth is found on this system
- */
-static int plymouth_command(const char* arg)
-{
-	const char *cmd = "/usr/bin/plymouth";
-	static int has_plymouth = 1;
-	pid_t pid;
-
-	if (!has_plymouth)
-		return 127;
-
-	pid = fork();
-	if (!pid) {
-		int fd = open("/dev/null", O_RDWR);
-		if (fd < 0)
-			exit(127);
-		dup2(fd, 0);
-		dup2(fd, 1);
-		dup2(fd, 2);
-		if (fd > 2)
-			close(fd);
-		execl(cmd, cmd, arg, (char *) NULL);
-		exit(127);
-	} else if (pid > 0) {
-		int status;
-		waitpid(pid, &status, 0);
-		if (status == 127)
-			has_plymouth = 0;
-		return status;
-	}
-	return 1;
-}
-#endif
-
 /*
  * Fix the tty modes and set reasonable defaults.
  */
@@ -138,8 +103,9 @@ static void tcinit(struct console *con)
 	struct termios lock;
 	int fd = con->fd;
 #ifdef TIOCGLCKTRMIOS
-	int i = (plymouth_command("--ping")) ? 20 : 0;
-
+	int i = (plymouth_command(MAGIC_PING)) ? PLYMOUTH_TERMIOS_FLAGS_DELAY : 0;
+	if (i)
+		plymouth_command(MAGIC_QUIT);
 	while (i-- > 0) {
 		/*
 		 * With plymouth the termios flags become changed after this
@@ -150,8 +116,6 @@ static void tcinit(struct console *con)
 			break;
 		if (!lock.c_iflag && !lock.c_oflag && !lock.c_cflag && !lock.c_lflag)
 			break;
-		if (i == 15 && plymouth_command("quit") != 0)
-			break;
 		sleep(1);
 	}
 	memset(&lock, 0, sizeof(struct termios));
diff --git a/term-utils/agetty.c b/term-utils/agetty.c
index 6d610c608..ab82fdbc8 100644
--- a/term-utils/agetty.c
+++ b/term-utils/agetty.c
@@ -41,6 +41,7 @@
 #include "all-io.h"
 #include "nls.h"
 #include "pathnames.h"
+#include "plymouth-ctrl.h"
 #include "c.h"
 #include "widechar.h"
 #include "ttyutils.h"
@@ -138,9 +139,6 @@ static int inotify_fd = AGETTY_RELOAD_FDNONE;
 static int netlink_fd = AGETTY_RELOAD_FDNONE;
 #endif
 
-#define AGETTY_PLYMOUTH		"/usr/bin/plymouth"
-#define AGETTY_PLYMOUTH_FDFILE	"/dev/null"
-
 /*
  * When multiple baud rates are specified on the command line, the first one
  * we will try is the first one specified.
@@ -309,7 +307,6 @@ static void log_warn (const char *, ...)
 static ssize_t append(char *dest, size_t len, const char  *sep, const char *src);
 static void check_username (const char* nm);
 static void login_options_to_argv(char *argv[], int *argc, char *str, char *username);
-static int plymouth_command(const char* arg);
 static void reload_agettys(void);
 
 /* Fake hostname for ut_host specified on command line. */
@@ -1180,8 +1177,9 @@ static void termio_init(struct options *op, struct termios *tp)
 	struct winsize ws;
 	struct termios lock;
 #ifdef TIOCGLCKTRMIOS
-	int i =  (plymouth_command("--ping") == 0) ? 30 : 0;
-
+	int i =  (plymouth_command(MAGIC_PING) == 0) ? PLYMOUTH_TERMIOS_FLAGS_DELAY : 0;
+	if (i)
+		plymouth_command(MAGIC_QUIT);
 	while (i-- > 0) {
 		/*
 		 * Even with TTYReset=no it seems with systemd or plymouth
@@ -1194,8 +1192,6 @@ static void termio_init(struct options *op, struct termios *tp)
 		if (!lock.c_iflag && !lock.c_oflag && !lock.c_cflag && !lock.c_lflag)
 			break;
 		debug("termios locked\n");
-		if (i == 15 && plymouth_command("quit") != 0)
-			break;
 		sleep(1);
 	}
 	memset(&lock, 0, sizeof(struct termios));
@@ -1725,7 +1721,9 @@ static void print_issue_file(struct options *op, struct termios *tp)
 /* Show login prompt, optionally preceded by /etc/issue contents. */
 static void do_prompt(struct options *op, struct termios *tp)
 {
+#ifdef AGETTY_RELOAD
 again:
+#endif
 	print_issue_file(op, tp);
 
 	if (op->flags & F_LOGINPAUSE) {
@@ -2596,40 +2594,6 @@ err:
 	log_err(_("checkname failed: %m"));
 }
 
-/*
- * For the case plymouth is found on this system
- */
-static int plymouth_command(const char* arg)
-{
-	static int has_plymouth = 1;
-	pid_t pid;
-
-	if (!has_plymouth)
-		return 127;
-
-	pid = fork();
-	if (!pid) {
-		int fd = open(AGETTY_PLYMOUTH_FDFILE, O_RDWR);
-
-		if (fd < 0)
-			err(EXIT_FAILURE,_("cannot open %s"),
-					AGETTY_PLYMOUTH_FDFILE);
-		dup2(fd, 0);
-		dup2(fd, 1);
-		dup2(fd, 2);
-		close(fd);
-		execl(AGETTY_PLYMOUTH, AGETTY_PLYMOUTH, arg, (char *) NULL);
-		exit(127);
-	} else if (pid > 0) {
-		int status;
-		waitpid(pid, &status, 0);
-		if (status == 127)
-			has_plymouth = 0;
-		return status;
-	}
-	return 1;
-}
-
 static void reload_agettys(void)
 {
 #ifdef AGETTY_RELOAD