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37f5bef63

Denys Vlasenko

2010-04-05

FAILED Duration: 28s

Subject

libbb: split update_utmp from login/getty in preparation to use it for telnetd

Binary

No binary (build failed)

Architecture & Compiler Flags

Architecture: x86_64-linux-gnu Compiler: gcc (Ubuntu 11.4.0-1ubuntu1~22.04.3) 11.4.0

—

Build Log

(log yok)

Commit Diff GitHub →

coreutils/who.c +1 -1 include/libbb.h +6 -0 init/halt.c +0 -1 libbb/Kbuild +2 -0 libbb/utmp.c +92 -0 loginutils/getty.c +2 -59 loginutils/login.c +14 -98

coreutils/who.c+1 -1

@@ -16,7 +16,7 @@
	*
	*----------------------------------------------------------------------
	*/
-	/* BB_AUDIT SUSv3 _NOT_ compliant -- missing options -b, -d, -H, -l, -m, -p, -q, -r, -s, -t, -T, -u; Missing argument 'file'. */
+	/* BB_AUDIT SUSv3 _NOT_ compliant -- missing options -b, -d, -l, -m, -p, -q, -r, -s, -t, -T, -u; Missing argument 'file'. */

	#include "libbb.h"
	#include <utmp.h>

include/libbb.h+6 -0

@@ -796,6 +796,12 @@ void die_if_bad_username(const char* name) FAST_FUNC;
	#define die_if_bad_username(name) ((void)(name))
	#endif

+	#if ENABLE_FEATURE_UTMP
+	void FAST_FUNC update_utmp(int new_type, const char short_tty, const char username, const char *opt_host);
+	#else
+	# define update_utmp(new_type, short_tty, username, opt_host) ((void)0)
+	#endif
+
	int execable_file(const char *name) FAST_FUNC;
	char find_execable(const char filename, char **PATHp) FAST_FUNC;
	int exists_execable(const char *filename) FAST_FUNC;

init/halt.c+0 -1

@@ -30,7 +30,6 @@ static void write_wtmp(void)
	if (uname(&uts) == 0)
	safe_strncpy(utmp.ut_host, uts.release, sizeof(utmp.ut_host));
	updwtmp(bb_path_wtmp_file, &utmp);
-
	}
	#else
	#define write_wtmp() ((void)0)

libbb/Kbuild+2 -0

@@ -120,6 +120,8 @@ lib-y += xgethostbyname.o
	lib-y += xreadlink.o
	lib-y += xrealloc_vector.o

+	lib-$(CONFIG_FEATURE_UTMP) += utmp.o
+
	# A mix of optimizations (why build stuff we know won't be used)
	# and objects which may fail to build (SELinux on selinux-less system)
	lib-$(CONFIG_SELINUX) += selinux_common.o

libbb/utmp.c+92 -0

@@ -0,0 +1,92 @@
+	/* vi: set sw=4 ts=4: */
+	/*
+	* utmp/wtmp support routines.
+	*
+	* Copyright (C) 2010 Denys Vlasenko
+	*
+	* Licensed under GPL version 2, see file LICENSE in this tarball for details.
+	*/
+	#include "libbb.h"
+	#include <utmp.h>
+
+	static void touch(const char *filename)
+	{
+	if (access(filename, R_OK \| W_OK) == -1)
+	close(open(filename, O_WRONLY \| O_CREAT, 0664));
+	}
+
+	/*
+	* Read "man utmp" to make sense out of it.
+	*/
+	void FAST_FUNC update_utmp(int new_type, const char short_tty, const char username, const char *opt_host)
+	{
+	struct utmp utent;
+	struct utmp *ut;
+	pid_t pid;
+
+	touch(_PATH_UTMP);
+	utmpname(_PATH_UTMP);
+	setutent();
+
+	pid = getpid();
+	/* Did init/getty/telnetd/sshd/... create an entry for us?
+	* It should be (new_type-1), but we'd also reuse
+	* any other potentially stale xxx_PROCESS entry */
+	while ((ut = getutent()) != NULL) {
+	if (ut->ut_pid == pid
+	// && ut->ut_line[0]
+	&& ut->ut_id[0] /* must have nonzero id */
+	&& ( ut->ut_type == INIT_PROCESS
+	\|\| ut->ut_type == LOGIN_PROCESS
+	\|\| ut->ut_type == USER_PROCESS
+	\|\| ut->ut_type == DEAD_PROCESS
+	)
+	) {
+	utent = ut; / struct copy */
+	if (ut->ut_type >= new_type) {
+	/* Stale record. Nuke hostname */
+	memset(utent.ut_host, 0, sizeof(utent.ut_host));
+	}
+	/* NB: pututline (see later) searches for matching utent
+	* using getutid(utent) - we must not change ut_id
+	* if we want exactly this record to be overwritten!
+	*/
+	break;
+	}
+	}
+	endutent();
+
+	if (!ut) {
+	/* Didn't find anything, create new one */
+	memset(&utent, 0, sizeof(utent));
+	utent.ut_pid = pid;
+	/* Invent our own ut_id. ut_id is only 4 chars wide.
+	* Try to fit something remotely meaningful... */
+	if (short_tty[0] == 'p') {
+	/* if "ptyXXX", map to "pXXX" */
+	/* if "pts/XX", map to "p/XX" */
+	utent.ut_id[0] = 'p';
+	strncpy(utent.ut_id + 1, short_tty + 3, sizeof(utent.ut_id)-1);
+	} else {
+	/* assuming it's "ttyXXXX", map to "XXXX" */
+	strncpy(utent.ut_id, short_tty + 3, sizeof(utent.ut_id));
+	}
+	}
+
+	utent.ut_type = new_type;
+	safe_strncpy(utent.ut_line, short_tty, sizeof(utent.ut_line));
+	safe_strncpy(utent.ut_user, username, sizeof(utent.ut_user));
+	if (opt_host)
+	safe_strncpy(utent.ut_host, opt_host, sizeof(utent.ut_host));
+	utent.ut_tv.tv_sec = time(NULL);
+
+	/* Update, or append new one */
+	setutent();
+	pututline(&utent);
+	endutent();
+
+	#if ENABLE_FEATURE_WTMP
+	touch(bb_path_wtmp_file);
+	updwtmp(bb_path_wtmp_file, &utent);
+	#endif
+	}

loginutils/getty.c+2 -59

@@ -19,7 +19,7 @@
	#include <syslog.h>

	#if ENABLE_FEATURE_UTMP
-	#include <utmp.h> /* updwtmp() */
+	#include <utmp.h> /* LOGIN_PROCESS */
	#endif

	#ifndef IUCLC
@@ -575,61 +575,6 @@ static void termios_final(struct options op, struct termios tp, struct chardat
	ioctl_or_perror_and_die(0, TCSETS, tp, "%s: TCSETS", op->tty);
	}

-	#if ENABLE_FEATURE_UTMP
-	static void touch(const char *filename)
-	{
-	if (access(filename, R_OK \| W_OK) == -1)
-	close(open(filename, O_WRONLY \| O_CREAT, 0664));
-	}
-
-	/* update_utmp - update our utmp entry */
-	static NOINLINE void update_utmp(const char line, char fakehost)
-	{
-	struct utmp ut;
-	struct utmp *utp;
-	int mypid = getpid();
-
-	/* In case we won't find an entry below... */
-	memset(&ut, 0, sizeof(ut));
-	safe_strncpy(ut.ut_id, line + 3, sizeof(ut.ut_id));
-
-	/*
-	* The utmp file holds miscellaneous information about things started by
-	* /sbin/init and other system-related events. Our purpose is to update
-	* the utmp entry for the current process, in particular the process type
-	* and the tty line we are listening to. Return successfully only if the
-	* utmp file can be opened for update, and if we are able to find our
-	* entry in the utmp file.
-	*/
-	touch(_PATH_UTMP);
-
-	utmpname(_PATH_UTMP);
-	setutent();
-	while ((utp = getutent()) != NULL) {
-	if (utp->ut_type == INIT_PROCESS && utp->ut_pid == mypid) {
-	memcpy(&ut, utp, sizeof(ut));
-	break;
-	}
-	}
-
-	strcpy(ut.ut_user, "LOGIN");
-	safe_strncpy(ut.ut_line, line, sizeof(ut.ut_line));
-	if (fakehost)
-	safe_strncpy(ut.ut_host, fakehost, sizeof(ut.ut_host));
-	ut.ut_tv.tv_sec = time(NULL);
-	ut.ut_type = LOGIN_PROCESS;
-	ut.ut_pid = mypid;
-
-	pututline(&ut);
-	endutent();
-
-	#if ENABLE_FEATURE_WTMP
-	touch(bb_path_wtmp_file);
-	updwtmp(bb_path_wtmp_file, &ut);
-	#endif
-	}
-	#endif /* CONFIG_FEATURE_UTMP */
-
	int getty_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
	int getty_main(int argc UNUSED_PARAM, char **argv)
	{
@@ -715,10 +660,8 @@ int getty_main(int argc UNUSED_PARAM, char **argv)
	tcsetpgrp(0, getpid());
	#endif

-	#if ENABLE_FEATURE_UTMP
	/* Update the utmp file. This tty is ours now! */
-	update_utmp(options.tty, fakehost);
-	#endif
+	update_utmp(LOGIN_PROCESS, options.tty, "LOGIN", fakehost);

	/* Initialize the termios settings (raw mode, eight-bit, blocking i/o). */
	debug("calling termios_init\n");

loginutils/login.c+14 -98

@@ -2,25 +2,26 @@
	/*
	* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
	*/
-
	#include "libbb.h"
	#include <syslog.h>
-	#include <utmp.h>
+	#if ENABLE_FEATURE_UTMP
+	# include <utmp.h> /* USER_PROCESS */
+	#endif
	#include <sys/resource.h>

	#if ENABLE_SELINUX
-	#include <selinux/selinux.h> /* for is_selinux_enabled() */
-	#include <selinux/get_context_list.h> /* for get_default_context() */
-	#include <selinux/flask.h> /* for security class definitions */
+	# include <selinux/selinux.h> /* for is_selinux_enabled() */
+	# include <selinux/get_context_list.h> /* for get_default_context() */
+	# include <selinux/flask.h> /* for security class definitions */
	#endif

	#if ENABLE_PAM
	/* PAM may include <locale.h>. We may need to undefine bbox's stub define: */
-	#undef setlocale
+	# undef setlocale
	/* For some obscure reason, PAM is not in pam/xxx, but in security/xxx.
	* Apparently they like to confuse people. */
-	#include <security/pam_appl.h>
-	#include <security/pam_misc.h>
+	# include <security/pam_appl.h>
+	# include <security/pam_misc.h>
	static const struct pam_conv conv = {
	misc_conv,
	NULL
@@ -36,87 +37,6 @@ enum {

	static char* short_tty;

-	#if ENABLE_FEATURE_UTMP
-	/* vv Taken from tinylogin utmp.c vv */
-	/*
-	* read_or_build_utent - see if utmp file is correct for this process
-	*
-	* System V is very picky about the contents of the utmp file
-	* and requires that a slot for the current process exist.
-	* The utmp file is scanned for an entry with the same process
-	* ID. If no entry exists the process exits with a message.
-	*
-	* The "picky" flag is for network and other logins that may
-	* use special flags. It allows the pid checks to be overridden.
-	* This means that getty should never invoke login with any
-	* command line flags.
-	*/
-
-	static void read_or_build_utent(struct utmp *utptr, int run_by_root)
-	{
-	struct utmp *ut;
-	pid_t pid = getpid();
-
-	setutent();
-
-	/* First, try to find a valid utmp entry for this process. */
-	/* If there is one, just use it. */
-	while ((ut = getutent()) != NULL) {
-	if (ut->ut_pid == pid && ut->ut_line[0] && ut->ut_id[0]
-	&& (ut->ut_type == LOGIN_PROCESS \|\| ut->ut_type == USER_PROCESS)
-	) {
-	utptr = ut; /* struct copy */
-	if (run_by_root) /* why only for root? */
-	memset(utptr->ut_host, 0, sizeof(utptr->ut_host));
-	return;
-	}
-	}
-
-	// Why? Do we require non-root to exec login from another
-	// former login process (e.g. login shell)? Some login's have
-	// login shells as children, so it won't work...
-	// if (!run_by_root)
-	// bb_error_msg_and_die("no utmp entry found");
-
-	/* Otherwise create a new one. */
-	memset(utptr, 0, sizeof(*utptr));
-	utptr->ut_type = LOGIN_PROCESS;
-	utptr->ut_pid = pid;
-	strncpy(utptr->ut_line, short_tty, sizeof(utptr->ut_line));
-	/* This one is only 4 chars wide. Try to fit something
-	* remotely meaningful by skipping "tty"... */
-	strncpy(utptr->ut_id, short_tty + 3, sizeof(utptr->ut_id));
-	strncpy(utptr->ut_user, "LOGIN", sizeof(utptr->ut_user));
-	utptr->ut_tv.tv_sec = time(NULL);
-	}
-
-	/*
-	* write_utent - put a USER_PROCESS entry in the utmp file
-	*
-	* write_utent changes the type of the current utmp entry to
-	* USER_PROCESS. the wtmp file will be updated as well.
-	*/
-	static void write_utent(struct utmp utptr, const char username)
-	{
-	utptr->ut_type = USER_PROCESS;
-	strncpy(utptr->ut_user, username, sizeof(utptr->ut_user));
-	utptr->ut_tv.tv_sec = time(NULL);
-	/* other fields already filled in by read_or_build_utent above */
-	setutent();
-	pututline(utptr);
-	endutent();
-	#if ENABLE_FEATURE_WTMP
-	if (access(bb_path_wtmp_file, R_OK\|W_OK) == -1) {
-	close(creat(bb_path_wtmp_file, 0664));
-	}
-	updwtmp(bb_path_wtmp_file, utptr);
-	#endif
-	}
-	#else /* !ENABLE_FEATURE_UTMP */
-	#define read_or_build_utent(utptr, run_by_root) ((void)0)
-	#define write_utent(utptr, username) ((void)0)
-	#endif /* !ENABLE_FEATURE_UTMP */
-
	#if ENABLE_FEATURE_NOLOGIN
	static void die_if_nologin(void)
	{
@@ -144,7 +64,7 @@ static void die_if_nologin(void)
	exit(EXIT_FAILURE);
	}
	#else
-	static ALWAYS_INLINE void die_if_nologin(void) {}
+	# define die_if_nologin() ((void)0)
	#endif

	#if ENABLE_FEATURE_SECURETTY && !ENABLE_PAM
@@ -286,11 +206,10 @@ int login_main(int argc UNUSED_PARAM, char **argv)
	unsigned opt;
	int count = 0;
	struct passwd *pw;
-	char opt_host = opt_host; / for compiler */
+	char *opt_host = NULL;
	char opt_user = opt_user; / for compiler */
	char *full_tty;
	IF_SELINUX(security_context_t user_sid = NULL;)
-	IF_FEATURE_UTMP(struct utmp utent;)
	#if ENABLE_PAM
	int pamret;
	pam_handle_t *pamh;
@@ -334,10 +253,7 @@ int login_main(int argc UNUSED_PARAM, char **argv)
	if (strncmp(full_tty, "/dev/", 5) == 0)
	short_tty += 5;

-	read_or_build_utent(&utent, run_by_root);
-
-	if (opt & LOGIN_OPT_h) {
-	IF_FEATURE_UTMP(safe_strncpy(utent.ut_host, opt_host, sizeof(utent.ut_host));)
+	if (opt_host) {
	fromhost = xasprintf(" on '%s' from '%s'", short_tty, opt_host);
	} else {
	fromhost = xasprintf(" on '%s'", short_tty);
@@ -461,8 +377,6 @@ int login_main(int argc UNUSED_PARAM, char **argv)
	if (pw->pw_uid != 0)
	die_if_nologin();

-	write_utent(&utent, username);
-
	IF_SELINUX(initselinux(username, full_tty, &user_sid));

	/* Try these, but don't complain if they fail.
@@ -470,6 +384,8 @@ int login_main(int argc UNUSED_PARAM, char **argv)
	fchown(0, pw->pw_uid, pw->pw_gid);
	fchmod(0, 0600);

+	update_utmp(USER_PROCESS, short_tty, username, run_by_root ? opt_host : NULL);
+
	/* We trust environment only if we run by root */
	if (ENABLE_LOGIN_SCRIPTS && run_by_root)
	run_login_script(pw, full_tty);