freebsd-dev/usr.bin/rctl/rctl.c
Pedro F. Giffuni 1de7b4b805 various: general adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

No functional change intended.
2017-11-27 15:37:16 +00:00

689 lines
14 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2010 The FreeBSD Foundation
* All rights reserved.
*
* This software was developed by Edward Tomasz Napierala under sponsorship
* from the FreeBSD Foundation.
*
* 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.
*
* $FreeBSD$
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <sys/rctl.h>
#include <sys/sysctl.h>
#include <assert.h>
#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <getopt.h>
#include <grp.h>
#include <libutil.h>
#include <pwd.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define RCTL_DEFAULT_BUFSIZE 128 * 1024
static int
parse_user(const char *s, id_t *uidp, const char *unexpanded_rule)
{
char *end;
struct passwd *pwd;
pwd = getpwnam(s);
if (pwd != NULL) {
*uidp = pwd->pw_uid;
return (0);
}
if (!isnumber(s[0])) {
warnx("malformed rule '%s': unknown user '%s'",
unexpanded_rule, s);
return (1);
}
*uidp = strtod(s, &end);
if ((size_t)(end - s) != strlen(s)) {
warnx("malformed rule '%s': trailing characters "
"after numerical id", unexpanded_rule);
return (1);
}
return (0);
}
static int
parse_group(const char *s, id_t *gidp, const char *unexpanded_rule)
{
char *end;
struct group *grp;
grp = getgrnam(s);
if (grp != NULL) {
*gidp = grp->gr_gid;
return (0);
}
if (!isnumber(s[0])) {
warnx("malformed rule '%s': unknown group '%s'",
unexpanded_rule, s);
return (1);
}
*gidp = strtod(s, &end);
if ((size_t)(end - s) != strlen(s)) {
warnx("malformed rule '%s': trailing characters "
"after numerical id", unexpanded_rule);
return (1);
}
return (0);
}
/*
* Replace human-readable number with its expanded form.
*/
static char *
expand_amount(const char *rule, const char *unexpanded_rule)
{
uint64_t num;
const char *subject, *subject_id, *resource, *action, *amount, *per;
char *copy, *expanded, *tofree;
int ret;
tofree = copy = strdup(rule);
if (copy == NULL) {
warn("strdup");
return (NULL);
}
subject = strsep(&copy, ":");
subject_id = strsep(&copy, ":");
resource = strsep(&copy, ":");
action = strsep(&copy, "=/");
amount = strsep(&copy, "/");
per = copy;
if (amount == NULL || strlen(amount) == 0) {
/*
* The "copy" has already been tinkered with by strsep().
*/
free(tofree);
copy = strdup(rule);
if (copy == NULL) {
warn("strdup");
return (NULL);
}
return (copy);
}
assert(subject != NULL);
assert(subject_id != NULL);
assert(resource != NULL);
assert(action != NULL);
if (expand_number(amount, &num)) {
warnx("malformed rule '%s': invalid numeric value '%s'",
unexpanded_rule, amount);
free(tofree);
return (NULL);
}
if (per == NULL) {
ret = asprintf(&expanded, "%s:%s:%s:%s=%ju",
subject, subject_id, resource, action, (uintmax_t)num);
} else {
ret = asprintf(&expanded, "%s:%s:%s:%s=%ju/%s",
subject, subject_id, resource, action, (uintmax_t)num, per);
}
if (ret <= 0) {
warn("asprintf");
free(tofree);
return (NULL);
}
free(tofree);
return (expanded);
}
static char *
expand_rule(const char *rule, bool resolve_ids)
{
id_t id;
const char *subject, *textid, *rest;
char *copy, *expanded, *resolved, *tofree;
int error, ret;
tofree = copy = strdup(rule);
if (copy == NULL) {
warn("strdup");
return (NULL);
}
subject = strsep(&copy, ":");
textid = strsep(&copy, ":");
if (textid == NULL) {
warnx("malformed rule '%s': missing subject", rule);
return (NULL);
}
if (copy != NULL)
rest = copy;
else
rest = "";
if (strcasecmp(subject, "u") == 0)
subject = "user";
else if (strcasecmp(subject, "g") == 0)
subject = "group";
else if (strcasecmp(subject, "p") == 0)
subject = "process";
else if (strcasecmp(subject, "l") == 0 ||
strcasecmp(subject, "c") == 0 ||
strcasecmp(subject, "class") == 0)
subject = "loginclass";
else if (strcasecmp(subject, "j") == 0)
subject = "jail";
if (resolve_ids &&
strcasecmp(subject, "user") == 0 && strlen(textid) > 0) {
error = parse_user(textid, &id, rule);
if (error != 0) {
free(tofree);
return (NULL);
}
ret = asprintf(&resolved, "%s:%d:%s", subject, (int)id, rest);
} else if (resolve_ids &&
strcasecmp(subject, "group") == 0 && strlen(textid) > 0) {
error = parse_group(textid, &id, rule);
if (error != 0) {
free(tofree);
return (NULL);
}
ret = asprintf(&resolved, "%s:%d:%s", subject, (int)id, rest);
} else {
ret = asprintf(&resolved, "%s:%s:%s", subject, textid, rest);
}
if (ret <= 0) {
warn("asprintf");
free(tofree);
return (NULL);
}
free(tofree);
expanded = expand_amount(resolved, rule);
free(resolved);
return (expanded);
}
static char *
humanize_ids(char *rule)
{
id_t id;
struct passwd *pwd;
struct group *grp;
const char *subject, *textid, *rest;
char *end, *humanized;
int ret;
subject = strsep(&rule, ":");
textid = strsep(&rule, ":");
if (textid == NULL)
errx(1, "rule passed from the kernel didn't contain subject");
if (rule != NULL)
rest = rule;
else
rest = "";
/* Replace numerical user and group ids with names. */
if (strcasecmp(subject, "user") == 0) {
id = strtod(textid, &end);
if ((size_t)(end - textid) != strlen(textid))
errx(1, "malformed uid '%s'", textid);
pwd = getpwuid(id);
if (pwd != NULL)
textid = pwd->pw_name;
} else if (strcasecmp(subject, "group") == 0) {
id = strtod(textid, &end);
if ((size_t)(end - textid) != strlen(textid))
errx(1, "malformed gid '%s'", textid);
grp = getgrgid(id);
if (grp != NULL)
textid = grp->gr_name;
}
ret = asprintf(&humanized, "%s:%s:%s", subject, textid, rest);
if (ret <= 0)
err(1, "asprintf");
return (humanized);
}
static int
str2int64(const char *str, int64_t *value)
{
char *end;
if (str == NULL)
return (EINVAL);
*value = strtoul(str, &end, 10);
if ((size_t)(end - str) != strlen(str))
return (EINVAL);
return (0);
}
static char *
humanize_amount(char *rule)
{
int64_t num;
const char *subject, *subject_id, *resource, *action, *amount, *per;
char *copy, *humanized, buf[6], *tofree;
int ret;
tofree = copy = strdup(rule);
if (copy == NULL)
err(1, "strdup");
subject = strsep(&copy, ":");
subject_id = strsep(&copy, ":");
resource = strsep(&copy, ":");
action = strsep(&copy, "=/");
amount = strsep(&copy, "/");
per = copy;
if (amount == NULL || strlen(amount) == 0 ||
str2int64(amount, &num) != 0) {
free(tofree);
return (rule);
}
assert(subject != NULL);
assert(subject_id != NULL);
assert(resource != NULL);
assert(action != NULL);
if (humanize_number(buf, sizeof(buf), num, "", HN_AUTOSCALE,
HN_DECIMAL | HN_NOSPACE) == -1)
err(1, "humanize_number");
if (per == NULL) {
ret = asprintf(&humanized, "%s:%s:%s:%s=%s",
subject, subject_id, resource, action, buf);
} else {
ret = asprintf(&humanized, "%s:%s:%s:%s=%s/%s",
subject, subject_id, resource, action, buf, per);
}
if (ret <= 0)
err(1, "asprintf");
free(tofree);
return (humanized);
}
/*
* Print rules, one per line.
*/
static void
print_rules(char *rules, int hflag, int nflag)
{
char *rule;
while ((rule = strsep(&rules, ",")) != NULL) {
if (rule[0] == '\0')
break; /* XXX */
if (nflag == 0)
rule = humanize_ids(rule);
if (hflag)
rule = humanize_amount(rule);
printf("%s\n", rule);
}
}
static void
enosys(void)
{
int error, racct_enable;
size_t racct_enable_len;
racct_enable_len = sizeof(racct_enable);
error = sysctlbyname("kern.racct.enable",
&racct_enable, &racct_enable_len, NULL, 0);
if (error != 0) {
if (errno == ENOENT)
errx(1, "RACCT/RCTL support not present in kernel; see rctl(8) for details");
err(1, "sysctlbyname");
}
if (racct_enable == 0)
errx(1, "RACCT/RCTL present, but disabled; enable using kern.racct.enable=1 tunable");
}
static int
add_rule(const char *rule, const char *unexpanded_rule)
{
int error;
error = rctl_add_rule(rule, strlen(rule) + 1, NULL, 0);
if (error != 0) {
if (errno == ENOSYS)
enosys();
warn("failed to add rule '%s'", unexpanded_rule);
}
return (error);
}
static int
show_limits(const char *filter, const char *unexpanded_rule,
int hflag, int nflag)
{
int error;
char *outbuf = NULL;
size_t outbuflen = RCTL_DEFAULT_BUFSIZE / 4;
for (;;) {
outbuflen *= 4;
outbuf = realloc(outbuf, outbuflen);
if (outbuf == NULL)
err(1, "realloc");
error = rctl_get_limits(filter, strlen(filter) + 1,
outbuf, outbuflen);
if (error == 0)
break;
if (errno == ERANGE)
continue;
if (errno == ENOSYS)
enosys();
warn("failed to get limits for '%s'", unexpanded_rule);
free(outbuf);
return (error);
}
print_rules(outbuf, hflag, nflag);
free(outbuf);
return (error);
}
static int
remove_rule(const char *filter, const char *unexpanded_rule)
{
int error;
error = rctl_remove_rule(filter, strlen(filter) + 1, NULL, 0);
if (error != 0) {
if (errno == ENOSYS)
enosys();
warn("failed to remove rule '%s'", unexpanded_rule);
}
return (error);
}
static char *
humanize_usage_amount(char *usage)
{
int64_t num;
const char *resource, *amount;
char *copy, *humanized, buf[6], *tofree;
int ret;
tofree = copy = strdup(usage);
if (copy == NULL)
err(1, "strdup");
resource = strsep(&copy, "=");
amount = copy;
assert(resource != NULL);
assert(amount != NULL);
if (str2int64(amount, &num) != 0 ||
humanize_number(buf, sizeof(buf), num, "", HN_AUTOSCALE,
HN_DECIMAL | HN_NOSPACE) == -1) {
free(tofree);
return (usage);
}
ret = asprintf(&humanized, "%s=%s", resource, buf);
if (ret <= 0)
err(1, "asprintf");
free(tofree);
return (humanized);
}
/*
* Query the kernel about a resource usage and print it out.
*/
static int
show_usage(const char *filter, const char *unexpanded_rule, int hflag)
{
int error;
char *copy, *outbuf = NULL, *tmp;
size_t outbuflen = RCTL_DEFAULT_BUFSIZE / 4;
for (;;) {
outbuflen *= 4;
outbuf = realloc(outbuf, outbuflen);
if (outbuf == NULL)
err(1, "realloc");
error = rctl_get_racct(filter, strlen(filter) + 1,
outbuf, outbuflen);
if (error == 0)
break;
if (errno == ERANGE)
continue;
if (errno == ENOSYS)
enosys();
warn("failed to show resource consumption for '%s'",
unexpanded_rule);
free(outbuf);
return (error);
}
copy = outbuf;
while ((tmp = strsep(&copy, ",")) != NULL) {
if (tmp[0] == '\0')
break; /* XXX */
if (hflag)
tmp = humanize_usage_amount(tmp);
printf("%s\n", tmp);
}
free(outbuf);
return (error);
}
/*
* Query the kernel about resource limit rules and print them out.
*/
static int
show_rules(const char *filter, const char *unexpanded_rule,
int hflag, int nflag)
{
int error;
char *outbuf = NULL;
size_t filterlen, outbuflen = RCTL_DEFAULT_BUFSIZE / 4;
if (filter != NULL)
filterlen = strlen(filter) + 1;
else
filterlen = 0;
for (;;) {
outbuflen *= 4;
outbuf = realloc(outbuf, outbuflen);
if (outbuf == NULL)
err(1, "realloc");
error = rctl_get_rules(filter, filterlen, outbuf, outbuflen);
if (error == 0)
break;
if (errno == ERANGE)
continue;
if (errno == ENOSYS)
enosys();
warn("failed to show rules for '%s'", unexpanded_rule);
free(outbuf);
return (error);
}
print_rules(outbuf, hflag, nflag);
free(outbuf);
return (error);
}
static void
usage(void)
{
fprintf(stderr, "usage: rctl [ -h ] [-a rule | -l filter | -r filter "
"| -u filter | filter]\n");
exit(1);
}
int
main(int argc, char **argv)
{
int ch, aflag = 0, hflag = 0, nflag = 0, lflag = 0, rflag = 0,
uflag = 0;
char *rule = NULL, *unexpanded_rule;
int i, cumulated_error, error;
while ((ch = getopt(argc, argv, "ahlnru")) != -1) {
switch (ch) {
case 'a':
aflag = 1;
break;
case 'h':
hflag = 1;
break;
case 'l':
lflag = 1;
break;
case 'n':
nflag = 1;
break;
case 'r':
rflag = 1;
break;
case 'u':
uflag = 1;
break;
case '?':
default:
usage();
}
}
argc -= optind;
argv += optind;
if (aflag + lflag + rflag + uflag > 1)
errx(1, "at most one of -a, -l, -r, or -u may be specified");
if (argc == 0) {
if (aflag + lflag + rflag + uflag == 0) {
rule = strdup("::");
show_rules(rule, rule, hflag, nflag);
return (0);
}
usage();
}
cumulated_error = 0;
for (i = 0; i < argc; i++) {
unexpanded_rule = argv[i];
/*
* Skip resolving if passed -n _and_ -a. Ignore -n otherwise,
* so we can still do "rctl -n u:root" and see the rules without
* resolving the UID.
*/
if (aflag != 0 && nflag != 0)
rule = expand_rule(unexpanded_rule, false);
else
rule = expand_rule(unexpanded_rule, true);
if (rule == NULL) {
cumulated_error++;
continue;
}
/*
* The reason for passing the unexpanded_rule is to make
* it easier for the user to search for the problematic
* rule in the passed input.
*/
if (aflag) {
error = add_rule(rule, unexpanded_rule);
} else if (lflag) {
error = show_limits(rule, unexpanded_rule,
hflag, nflag);
} else if (rflag) {
error = remove_rule(rule, unexpanded_rule);
} else if (uflag) {
error = show_usage(rule, unexpanded_rule, hflag);
} else {
error = show_rules(rule, unexpanded_rule,
hflag, nflag);
}
if (error != 0)
cumulated_error++;
free(rule);
}
return (cumulated_error);
}