diff options
author | ed <ed@FreeBSD.org> | 2009-12-03 15:48:24 +0000 |
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committer | ed <ed@FreeBSD.org> | 2009-12-03 15:48:24 +0000 |
commit | 879c7d27302e0fb0654529de4b88f210ee11b022 (patch) | |
tree | c0f0fe174257910e3a7d7dcda57958d8ade8bfa9 /libexec | |
parent | b6cdcc994062fb93affd9d473219a5f06d4029ff (diff) | |
download | FreeBSD-src-879c7d27302e0fb0654529de4b88f210ee11b022.zip FreeBSD-src-879c7d27302e0fb0654529de4b88f210ee11b022.tar.gz |
Add a new library: libulog.
One of the things I really want to do, is to get rid of the limitations
of our current utmp(5) mechanism:
- It only allows 8 byte TTY device names.
- The hostname only allows 16 bytes of storage.
I'm not a big fan of <utmpx.h>, but I think we should at least try to
add parts of it. Unfortunately we cannot implement <utmpx.h>, because we
miss various fields, such as ut_id, ut_pid, etc. The API provided by
libulog shares some similarities with <utmpx.h>, so it shouldn't be too
hard to port these applications eventually. In most simple cases, it
should just be a matter of removing the ulog_ prefix everywhere.
As a bonus, it also implements a function called ulog_login_pseudo(),
which allows unprivileged applications to write log entries, provided
they have a valid file descriptor to a pseudo-terminal master device.
libulog will allow a smoother transition to a new file format by adding
a library interface to deal with utmp/wtmp/lastlog files. I initially
thought about adding the functionality to libutil, but because I'm not
planning on keeping this library around forever, we'd better keep it
separated.
Next items on the todo list:
1. Port applications in the base system (and ports) to libulog, instead
of letting them use <utmp.h>.
2. Remove <utmp.h>, implement <utmpx.h> and reimplement this library on
top.
3. Port as many applications as possible back to <utmpx.h>.
Diffstat (limited to 'libexec')
-rw-r--r-- | libexec/Makefile | 1 | ||||
-rw-r--r-- | libexec/ulog-helper/Makefile | 13 | ||||
-rw-r--r-- | libexec/ulog-helper/ulog-helper.c | 81 |
3 files changed, 95 insertions, 0 deletions
diff --git a/libexec/Makefile b/libexec/Makefile index 26a8ff2..78953b4 100644 --- a/libexec/Makefile +++ b/libexec/Makefile @@ -29,6 +29,7 @@ SUBDIR= ${_atrun} \ ${_telnetd} \ tftpd \ ${_tftp-proxy} \ + ulog-helper \ ${_ypxfr} .if ${MK_AT} != "no" diff --git a/libexec/ulog-helper/Makefile b/libexec/ulog-helper/Makefile new file mode 100644 index 0000000..c420200 --- /dev/null +++ b/libexec/ulog-helper/Makefile @@ -0,0 +1,13 @@ +# $FreeBSD$ + +PROG= ulog-helper +BINOWN= root +BINMODE=4555 +NO_MAN= + +DPADD= ${LIBULOG} +LDADD= -lulog + +WARNS?= 6 + +.include <bsd.prog.mk> diff --git a/libexec/ulog-helper/ulog-helper.c b/libexec/ulog-helper/ulog-helper.c new file mode 100644 index 0000000..ecf6507 --- /dev/null +++ b/libexec/ulog-helper/ulog-helper.c @@ -0,0 +1,81 @@ +/*- + * Copyright (c) 2009 Ed Schouten <ed@FreeBSD.org> + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include <pwd.h> +#include <unistd.h> +#include <stdlib.h> +#include <string.h> +#include <sysexits.h> +#include <ulog.h> + +/* + * This setuid helper utility writes user login records to disk. + * Unprivileged processes are not capable of writing records to utmp, + * wtmp and lastlog, but we do want to allow this for pseudo-terminals. + * Because a file descriptor to a pseudo-terminal master device can only + * be obtained by processes using the pseudo-terminal, we expect such a + * descriptor on stdin. + * + * It uses the real user ID of the calling process to determine the + * username. It does allow users to log arbitrary hostnames. + */ + +int +main(int argc, char *argv[]) +{ + const char *line; + + /* Device line name. */ + if ((line = ptsname(STDIN_FILENO)) == NULL) + return (EX_USAGE); + + if ((argc == 2 || argc == 3) && strcmp(argv[1], "login") == 0) { + struct passwd *pwd; + const char *host = NULL; + + /* Username. */ + pwd = getpwuid(getuid()); + if (pwd == NULL) + return (EX_OSERR); + + /* Hostname. */ + if (argc == 3) + host = argv[2]; + + if (ulog_login(line, pwd->pw_name, host) != 0) + return (EX_OSFILE); + return (EX_OK); + } else if (argc == 2 && strcmp(argv[1], "logout") == 0) { + if (ulog_logout(line) != 0) + return (EX_OSFILE); + return (EX_OK); + } + + return (EX_USAGE); +} |