procps/skill.c
Craig Small 536cea324b kill: -l space between name parses correctly
kill -lHUP would work correctly, but kill -l HUP would not.

The list option in kill was hit by a quirk of getopt_long where an
option with an optional argument would not attempt to get the argument
beyond the space, even though a mandatory argument would do that.

The fix is a kludge to scan to the next argument and if it looks
like something we can use, use it. Lucky for us, the list option is
one where parsing can stop immediately.

Thanks to Brian Vandenberg for the way forward.

References:
 http://stackoverflow.com/questions/1052746/getopt-does-not-parse-optional-arguments-to-parameters
 https://bugs.debian.org/854407
2017-02-07 22:05:18 +11:00

768 lines
18 KiB
C

/*
* skill.c - send a signal to process
* Copyright 1998-2002 by Albert Cahalan
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <ctype.h>
#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <getopt.h>
#include <limits.h>
#include <pwd.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/resource.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/types.h>
#include <unistd.h>
#include "c.h"
#include "fileutils.h"
#include "nsutils.h"
#include "strutils.h"
#include "nls.h"
#include "xalloc.h"
#include "proc/pwcache.h"
#include "proc/sig.h"
#include "proc/devname.h"
#include "proc/procps.h" /* char *pwcache_get_user(uid_t uid) */
#include "proc/readproc.h"
#include "proc/version.h" /* procps_version */
#include "rpmatch.h"
#define DEFAULT_NICE 4
struct run_time_conf_t {
int fast;
int interactive;
int verbose;
int warnings;
int noaction;
int debugging;
};
static int tty_count, uid_count, cmd_count, pid_count, namespace_count;
static int *ttys;
static uid_t *uids;
static const char **cmds;
static int *pids;
static char **namespaces;
static int ns_pid;
static proc_t ns_task;
#define ENLIST(thing,addme) do{ \
if(!thing##s) thing##s = xmalloc(sizeof(*thing##s)*saved_argc); \
thing##s[thing##_count++] = addme; \
}while(0)
static int my_pid;
static int saved_argc;
static int sig_or_pri;
enum {
PROG_UNKNOWN,
PROG_KILL,
PROG_SKILL,
PROG_SNICE
};
static int program = PROG_UNKNOWN;
static void display_kill_version(void)
{
fprintf(stdout, PROCPS_NG_VERSION);
}
static int ns_flags = 0x3f;
static int parse_namespaces(char *optarg)
{
char *ptr = optarg, *tmp;
int len, id;
ns_flags = 0;
while (1) {
if (strchr(ptr, ',') == NULL) {
len = -1;
tmp = strdup(ptr);
} else {
len = strchr(ptr, ',') - ptr;
tmp = strndup(ptr, len);
}
id = get_ns_id(tmp);
if (id == -1) {
fprintf(stderr, "%s is not a valid namespace\n", tmp);
free(tmp);
return 1;
}
ns_flags |= (1 << id);
ENLIST(namespace, tmp);
if (len == -1)
break;
ptr+= len + 1;
}
return 0;
}
/* kill or nice a process */
static void hurt_proc(int tty, int uid, int pid, const char *restrict const cmd,
struct run_time_conf_t *run_time)
{
int failed;
char dn_buf[1000];
dev_to_tty(dn_buf, 999, tty, pid, ABBREV_DEV);
if (run_time->interactive) {
char *buf;
size_t len = 0;
fprintf(stderr, "%-8s %-8s %5d %-16.16s ? ",
(char *)dn_buf, pwcache_get_user(uid), pid, cmd);
fflush (stdout);
if (getline(&buf, &len, stdin) == -1)
return;
if (rpmatch(buf) < 1) {
free(buf);
return;
}
free(buf);
}
/* do the actual work */
errno = 0;
if (program == PROG_SKILL)
failed = kill(pid, sig_or_pri);
else
failed = setpriority(PRIO_PROCESS, pid, sig_or_pri);
if ((run_time->warnings && failed) || run_time->debugging || run_time->verbose) {
fprintf(stderr, "%-8s %-8s %5d %-16.16s ",
(char *)dn_buf, pwcache_get_user(uid), pid, cmd);
perror("");
return;
}
if (run_time->interactive)
return;
if (run_time->noaction) {
printf("%d\n", pid);
return;
}
}
/* check one process */
static void check_proc(int pid, struct run_time_conf_t *run_time)
{
char buf[128];
struct stat statbuf;
proc_t task;
char *tmp;
int tty;
int fd;
int i;
if (pid == my_pid || pid == 0)
return;
/* pid (cmd) state ppid pgrp session tty */
sprintf(buf, "/proc/%d/stat", pid);
fd = open(buf, O_RDONLY);
if (fd == -1) {
/* process exited maybe */
if (run_time->warnings)
xwarn(_("cannot open file %s"), buf);
return;
}
fstat(fd, &statbuf);
if (uids) {
/* check the EUID */
i = uid_count;
while (i--)
if (uids[i] == statbuf.st_uid)
break;
if (i == -1)
goto closure;
}
if (read(fd, buf, 128) <= 0)
goto closure;
buf[127] = '\0';
tmp = strrchr(buf, ')');
*tmp++ = '\0';
i = 5;
while (i--)
while (*tmp++ != ' ')
/* scan to find tty */ ;
tty = atoi(tmp);
if (ttys) {
i = tty_count;
while (i--)
if (ttys[i] == tty)
break;
if (i == -1)
goto closure;
}
tmp = strchr(buf, '(') + 1;
if (cmds) {
i = cmd_count;
/* fast comparison trick -- useful? */
while (i--)
if (cmds[i][0] == *tmp && !strcmp(cmds[i], tmp))
break;
if (i == -1)
goto closure;
}
if (ns_pid) {
if (ns_read(pid, &task))
goto closure;
for (i = 0; i < NUM_NS; i++) {
if (ns_flags & (1 << i)) {
if (task.ns[i] != ns_task.ns[i])
goto closure;
}
}
}
/* This is where we kill/nice something. */
/* for debugging purposes?
fprintf(stderr, "PID %d, UID %d, TTY %d,%d, COMM %s\n",
pid, statbuf.st_uid, tty >> 8, tty & 0xf, tmp);
*/
hurt_proc(tty, statbuf.st_uid, pid, tmp, run_time);
closure:
/* kill/nice _first_ to avoid PID reuse */
close(fd);
}
/* debug function */
static void show_lists(void)
{
int i;
fprintf(stderr, "signal: %d\n", sig_or_pri);
fprintf(stderr, "%d TTY: ", tty_count);
if (ttys) {
i = tty_count;
while (i--) {
fprintf(stderr, "%d,%d%c", (ttys[i] >> 8) & 0xff,
ttys[i] & 0xff, i ? ' ' : '\n');
}
} else
fprintf(stderr, "\n");
fprintf(stderr, "%d UID: ", uid_count);
if (uids) {
i = uid_count;
while (i--)
fprintf(stderr, "%d%c", uids[i], i ? ' ' : '\n');
} else
fprintf(stderr, "\n");
fprintf(stderr, "%d PID: ", pid_count);
if (pids) {
i = pid_count;
while (i--)
fprintf(stderr, "%d%c", pids[i], i ? ' ' : '\n');
} else
fprintf(stderr, "\n");
fprintf(stderr, "%d CMD: ", cmd_count);
if (cmds) {
i = cmd_count;
while (i--)
fprintf(stderr, "%s%c", cmds[i], i ? ' ' : '\n');
} else
fprintf(stderr, "\n");
}
/* iterate over all PIDs */
static void iterate(struct run_time_conf_t *run_time)
{
int pid;
DIR *d;
struct dirent *de;
if (pids) {
pid = pid_count;
while (pid--)
check_proc(pids[pid], run_time);
return;
}
#if 0
/* could setuid() and kill -1 to have the kernel wipe out a user */
if (!ttys && !cmds && !pids && !run_time->interactive) {
}
#endif
d = opendir("/proc");
if (!d)
xerr(EXIT_FAILURE, "/proc");
while ((de = readdir(d))) {
if (de->d_name[0] > '9')
continue;
if (de->d_name[0] < '1')
continue;
pid = atoi(de->d_name);
if (pid)
check_proc(pid, run_time);
}
closedir(d);
}
/* kill help */
static void __attribute__ ((__noreturn__)) kill_usage(FILE * out)
{
fputs(USAGE_HEADER, out);
fprintf(out,
_(" %s [options] <pid> [...]\n"), program_invocation_short_name);
fputs(USAGE_OPTIONS, out);
fputs(_(" <pid> [...] send signal to every <pid> listed\n"), out);
fputs(_(" -<signal>, -s, --signal <signal>\n"
" specify the <signal> to be sent\n"), out);
fputs(_(" -l, --list=[<signal>] list all signal names, or convert one to a name\n"), out);
fputs(_(" -L, --table list all signal names in a nice table\n"), out);
fputs(USAGE_SEPARATOR, out);
fputs(USAGE_HELP, out);
fputs(USAGE_VERSION, out);
fprintf(out, USAGE_MAN_TAIL("kill(1)"));
exit(out == stderr ? EXIT_FAILURE : EXIT_SUCCESS);
}
/* skill and snice help */
static void __attribute__ ((__noreturn__)) skillsnice_usage(FILE * out)
{
fputs(USAGE_HEADER, out);
if (program == PROG_SKILL) {
fprintf(out,
_(" %s [signal] [options] <expression>\n"),
program_invocation_short_name);
} else {
fprintf(out,
_(" %s [new priority] [options] <expression>\n"),
program_invocation_short_name);
}
fputs(USAGE_OPTIONS, out);
fputs(_(" -f, --fast fast mode (not implemented)\n"), out);
fputs(_(" -i, --interactive interactive\n"), out);
fputs(_(" -l, --list list all signal names\n"), out);
fputs(_(" -L, --table list all signal names in a nice table\n"), out);
fputs(_(" -n, --no-action do not actually kill processes; just print what would happen\n"), out);
fputs(_(" -v, --verbose explain what is being done\n"), out);
fputs(_(" -w, --warnings enable warnings (not implemented)\n"), out);
fputs(USAGE_SEPARATOR, out);
fputs(_("Expression can be: terminal, user, pid, command.\n"
"The options below may be used to ensure correct interpretation.\n"), out);
fputs(_(" -c, --command <command> expression is a command name\n"), out);
fputs(_(" -p, --pid <pid> expression is a process id number\n"), out);
fputs(_(" -t, --tty <tty> expression is a terminal\n"), out);
fputs(_(" -u, --user <username> expression is a username\n"), out);
fputs(USAGE_SEPARATOR, out);
fputs(_("Alternatively, expression can be:\n"), out);
fputs(_(" --ns <pid> match the processes that belong to the same\n"
" namespace as <pid>\n"), out);
fputs(_(" --nslist <ns,...> list which namespaces will be considered for\n"
" the --ns option; available namespaces are\n:"
" ipc, mnt, net, pid, user, uts\n"), out);
fputs(USAGE_SEPARATOR, out);
fputs(USAGE_SEPARATOR, out);
fputs(USAGE_HELP, out);
fputs(USAGE_VERSION, out);
if (program == PROG_SKILL) {
fprintf(out,
_("\n"
"The default signal is TERM. Use -l or -L to list available signals.\n"
"Particularly useful signals include HUP, INT, KILL, STOP, CONT, and 0.\n"
"Alternate signals may be specified in three ways: -SIGKILL -KILL -9\n"));
fprintf(out, USAGE_MAN_TAIL("skill(1)"));
} else {
fprintf(out,
_("\n"
"The default priority is +4. (snice +4 ...)\n"
"Priority numbers range from +20 (slowest) to -20 (fastest).\n"
"Negative priority numbers are restricted to administrative users.\n"));
fprintf(out, USAGE_MAN_TAIL("snice(1)"));
}
exit(out == stderr ? EXIT_FAILURE : EXIT_SUCCESS);
}
static int skill_sig_option(int *argc, char **argv)
{
int i;
int signo = -1;
for (i = 1; i < *argc; i++) {
if (argv[i][0] == '-') {
signo = signal_name_to_number(argv[i] + 1);
if (-1 < signo) {
memmove(argv + i, argv + i + 1,
sizeof(char *) * (*argc - i));
(*argc)--;
return signo;
}
}
}
return signo;
}
/* kill */
static void __attribute__ ((__noreturn__))
kill_main(int argc, char **argv)
{
int signo, i;
int loop = 1;
long pid;
int exitvalue = EXIT_SUCCESS;
int optindex;
char *sig_option;
static const struct option longopts[] = {
{"list", optional_argument, NULL, 'l'},
{"table", no_argument, NULL, 'L'},
{"signal", required_argument, NULL, 's'},
{"help", no_argument, NULL, 'h'},
{"version", no_argument, NULL, 'V'},
{NULL, 0, NULL, 0}
};
setlocale (LC_ALL, "");
bindtextdomain(PACKAGE, LOCALEDIR);
textdomain(PACKAGE);
atexit(close_stdout);
if (argc < 2)
kill_usage(stderr);
signo = skill_sig_option(&argc, argv);
if (signo < 0)
signo = SIGTERM;
opterr=0; /* suppress errors on -123 */
while (loop == 1 && (i = getopt_long(argc, argv, "l::Ls:hV", longopts, &optindex)) != -1)
switch (i) {
case 'l':
sig_option = NULL;
if (optarg) {
sig_option = optarg;
} else if (argv[optindex+1] != NULL && argv[optindex+1][0] != '-') {
sig_option = argv[optindex+1];
}
if (sig_option) {
char *s;
s = strtosig(sig_option);
if (s)
printf("%s\n", s);
else
xwarnx(_("unknown signal name %s"),
sig_option);
free(s);
} else {
unix_print_signals();
}
exit(EXIT_SUCCESS);
case 'L':
pretty_print_signals();
exit(EXIT_SUCCESS);
case 's':
signo = signal_name_to_number(optarg);
break;
case 'h':
kill_usage(stdout);
case 'V':
display_kill_version();
exit(EXIT_SUCCESS);
case '?':
if (!isdigit(optopt)) {
xwarnx(_("invalid argument %c"), optopt);
kill_usage(stderr);
} else {
/* Special case for signal digit negative
* PIDs */
pid = atoi(argv[optind]);
if (kill((pid_t)pid, signo) != 0)
exitvalue = EXIT_FAILURE;
exit(exitvalue);
}
loop=0;
break;
default:
kill_usage(stderr);
}
argc -= optind;
argv += optind;
if (argc < 1)
kill_usage(stderr);
for (i = 0; i < argc; i++) {
pid = strtol_or_err(argv[i], _("failed to parse argument"));
if (!kill((pid_t) pid, signo))
continue;
error(0, errno, "(%ld)", pid);
exitvalue = EXIT_FAILURE;
continue;
}
exit(exitvalue);
}
#if 0
static void _skillsnice_usage(int line)
{
fprintf(stderr, _("something at line %d\n"), line);
skillsnice_usage(stderr);
}
#define skillsnice_usage() _skillsnice_usage(__LINE__)
#endif
#define NEXTARG (argc?( argc--, ((argptr=*++argv)) ):NULL)
/* common skill/snice argument parsing code */
static int snice_prio_option(int *argc, char **argv)
{
int i = 1, nargs = *argc;
long prio = DEFAULT_NICE;
while (i < nargs) {
if ((argv[i][0] == '-' || argv[i][0] == '+')
&& isdigit(argv[i][1])) {
prio = strtol_or_err(argv[i],
_("failed to parse argument"));
if (prio < INT_MIN || INT_MAX < prio)
xerrx(EXIT_FAILURE,
_("priority %lu out of range"), prio);
nargs--;
if (nargs - i)
memmove(argv + i, argv + i + 1,
sizeof(char *) * (nargs - i));
} else
i++;
}
*argc = nargs;
return (int)prio;
}
static void skillsnice_parse(int argc,
char **argv, struct run_time_conf_t *run_time)
{
int signo = -1;
int prino = DEFAULT_NICE;
int ch, i;
enum {
NS_OPTION = CHAR_MAX + 1,
NSLIST_OPTION,
};
static const struct option longopts[] = {
{"command", required_argument, NULL, 'c'},
{"debug", no_argument, NULL, 'd'},
{"fast", no_argument, NULL, 'f'},
{"interactive", no_argument, NULL, 'i'},
{"list", no_argument, NULL, 'l'},
{"no-action", no_argument, NULL, 'n'},
{"pid", required_argument, NULL, 'p'},
{"table", no_argument, NULL, 'L'},
{"tty", required_argument, NULL, 't'},
{"user", required_argument, NULL, 'u'},
{"ns", required_argument, NULL, NS_OPTION},
{"nslist", required_argument, NULL, NSLIST_OPTION},
{"verbose", no_argument, NULL, 'v'},
{"warnings", no_argument, NULL, 'w'},
{"help", no_argument, NULL, 'h'},
{"version", no_argument, NULL, 'V'},
{NULL, 0, NULL, 0}
};
if (argc < 2)
skillsnice_usage(stderr);
sig_or_pri = -1;
if (program == PROG_SNICE)
prino = snice_prio_option(&argc, argv);
else if (program == PROG_SKILL) {
signo = skill_sig_option(&argc, argv);
if (-1 < signo)
sig_or_pri = signo;
}
pid_count = 0;
while ((ch =
getopt_long(argc, argv, "c:dfilnp:Lt:u:vwhV", longopts,
NULL)) != -1)
switch (ch) {
case 'c':
ENLIST(cmd, optarg);
break;
case 'd':
run_time->debugging = 1;
break;
case 'f':
run_time->fast = 1;
break;
case 'i':
run_time->interactive = 1;
break;
case 'l':
unix_print_signals();
exit(EXIT_SUCCESS);
case 'n':
run_time->noaction = 1;
break;
case 'p':
ENLIST(pid,
strtol_or_err(optarg,
_("failed to parse argument")));
pid_count++;
break;
case 'L':
pretty_print_signals();
exit(EXIT_SUCCESS);
case 't':
{
struct stat sbuf;
char path[32];
snprintf(path, 32, "/dev/%s", optarg);
if (stat(path, &sbuf) >= 0
&& S_ISCHR(sbuf.st_mode)) {
ENLIST(tty, sbuf.st_rdev);
}
}
break;
case 'u':
{
struct passwd *passwd_data;
passwd_data = getpwnam(optarg);
if (passwd_data) {
ENLIST(uid, passwd_data->pw_uid);
}
}
break;
case NS_OPTION:
ns_pid = atoi(optarg);
if (ns_pid == 0) {
xwarnx(_("invalid pid number %s"), optarg);
kill_usage(stderr);
}
if (ns_read(ns_pid, &ns_task)) {
xwarnx(_("error reading reference namespace "
"information"));
kill_usage(stderr);
}
break;
case NSLIST_OPTION:
if (parse_namespaces(optarg)) {
xwarnx(_("invalid namespace list"));
kill_usage(stderr);
}
break;
case 'v':
run_time->verbose = 1;
break;
case 'w':
run_time->warnings = 1;
break;
case 'h':
skillsnice_usage(stdout);
case 'V':
display_kill_version();
exit(EXIT_SUCCESS);
default:
skillsnice_usage(stderr);
}
argc -= optind;
argv += optind;
for (i = 0; i < argc; i++) {
long num;
char *end = NULL;
errno = 0;
num = strtol(argv[0], &end, 10);
if (errno == 0 && argv[0] != end && end != NULL && *end == '\0') {
ENLIST(pid, num);
pid_count++;
} else {
ENLIST(cmd, argv[0]);
}
argv++;
}
/* No more arguments to process. Must sanity check. */
if (!tty_count && !uid_count && !cmd_count && !pid_count && !ns_pid)
xerrx(EXIT_FAILURE, _("no process selection criteria"));
if ((run_time->fast | run_time->interactive | run_time->
verbose | run_time->warnings | run_time->noaction) & ~1)
xerrx(EXIT_FAILURE, _("general flags may not be repeated"));
if (run_time->interactive
&& (run_time->verbose | run_time->fast | run_time->noaction))
xerrx(EXIT_FAILURE, _("-i makes no sense with -v, -f, and -n"));
if (run_time->verbose && (run_time->interactive | run_time->fast))
xerrx(EXIT_FAILURE, _("-v makes no sense with -i and -f"));
if (run_time->noaction) {
program = PROG_SKILL;
/* harmless */
sig_or_pri = 0;
}
if (program == PROG_SNICE)
sig_or_pri = prino;
else if (sig_or_pri < 0)
sig_or_pri = SIGTERM;
}
/* main body */
int main(int argc, char ** argv)
{
#ifdef HAVE_PROGRAM_INVOCATION_NAME
program_invocation_name = program_invocation_short_name;
#endif
struct run_time_conf_t run_time;
memset(&run_time, 0, sizeof(struct run_time_conf_t));
my_pid = getpid();
if (strcmp(program_invocation_short_name, "kill") == 0 ||
strcmp(program_invocation_short_name, "lt-kill") == 0)
program = PROG_KILL;
else if (strcmp(program_invocation_short_name, "skill") == 0 ||
strcmp(program_invocation_short_name, "lt-skill") == 0)
program = PROG_SKILL;
else if (strcmp(program_invocation_short_name, "snice") == 0 ||
strcmp(program_invocation_short_name, "lt-snice") == 0)
program = PROG_SNICE;
switch (program) {
case PROG_SNICE:
case PROG_SKILL:
setpriority(PRIO_PROCESS, my_pid, -20);
skillsnice_parse(argc, argv, &run_time);
if (run_time.debugging)
show_lists();
iterate(&run_time);
break;
case PROG_KILL:
kill_main(argc, argv);
break;
default:
fprintf(stderr, _("skill: \"%s\" is not supported\n"),
program_invocation_short_name);
fprintf(stderr, USAGE_MAN_TAIL("skill(1)"));
return EXIT_FAILURE;
}
return EXIT_SUCCESS;
}