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freebsd-dev/sys/kern/kern_rctl.c
Kip Macy 8451d0dd78 In order to maximize the re-usability of kernel code in user space this 
patch modifies makesyscalls.sh to prefix all of the non-compatibility
calls (e.g. not linux_, freebsd32_) with sys_ and updates the kernel
entry points and all places in the code that use them. It also
fixes an additional name space collision between the kernel function
psignal and the libc function of the same name by renaming the kernel
psignal kern_psignal(). By introducing this change now we will ease future
MFCs that change syscalls.

Reviewed by:	rwatson
Approved by:	re (bz)
2011-09-16 13:58:51 +00:00

1839 lines
44 KiB
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Raw Blame History

/*-
* 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/param.h>
#include <sys/bus.h>
#include <sys/malloc.h>
#include <sys/queue.h>
#include <sys/refcount.h>
#include <sys/jail.h>
#include <sys/kernel.h>
#include <sys/limits.h>
#include <sys/loginclass.h>
#include <sys/priv.h>
#include <sys/proc.h>
#include <sys/racct.h>
#include <sys/rctl.h>
#include <sys/resourcevar.h>
#include <sys/sx.h>
#include <sys/sysent.h>
#include <sys/sysproto.h>
#include <sys/systm.h>
#include <sys/types.h>
#include <sys/eventhandler.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/rwlock.h>
#include <sys/sbuf.h>
#include <sys/taskqueue.h>
#include <sys/tree.h>
#include <vm/uma.h>
#ifdef RCTL
#ifndef RACCT
#error "The RCTL option requires the RACCT option"
#endif
FEATURE(rctl, "Resource Limits");
#define HRF_DEFAULT 0
#define HRF_DONT_INHERIT 1
#define HRF_DONT_ACCUMULATE 2
/* Default buffer size for rctl_get_rules(2). */
#define RCTL_DEFAULT_BUFSIZE 4096
#define RCTL_LOG_BUFSIZE 128
/*
* 'rctl_rule_link' connects a rule with every racct it's related to.
* For example, rule 'user:X:openfiles:deny=N/process' is linked
* with uidinfo for user X, and to each process of that user.
*/
struct rctl_rule_link {
LIST_ENTRY(rctl_rule_link) rrl_next;
struct rctl_rule *rrl_rule;
int rrl_exceeded;
};
struct dict {
const char *d_name;
int d_value;
};
static struct dict subjectnames[] = {
{ "process", RCTL_SUBJECT_TYPE_PROCESS },
{ "user", RCTL_SUBJECT_TYPE_USER },
{ "loginclass", RCTL_SUBJECT_TYPE_LOGINCLASS },
{ "jail", RCTL_SUBJECT_TYPE_JAIL },
{ NULL, -1 }};
static struct dict resourcenames[] = {
{ "cputime", RACCT_CPU },
{ "datasize", RACCT_DATA },
{ "stacksize", RACCT_STACK },
{ "coredumpsize", RACCT_CORE },
{ "memoryuse", RACCT_RSS },
{ "memorylocked", RACCT_MEMLOCK },
{ "maxproc", RACCT_NPROC },
{ "openfiles", RACCT_NOFILE },
{ "vmemoryuse", RACCT_VMEM },
{ "pseudoterminals", RACCT_NPTS },
{ "swapuse", RACCT_SWAP },
{ "nthr", RACCT_NTHR },
{ "msgqqueued", RACCT_MSGQQUEUED },
{ "msgqsize", RACCT_MSGQSIZE },
{ "nmsgq", RACCT_NMSGQ },
{ "nsem", RACCT_NSEM },
{ "nsemop", RACCT_NSEMOP },
{ "nshm", RACCT_NSHM },
{ "shmsize", RACCT_SHMSIZE },
{ "wallclock", RACCT_WALLCLOCK },
{ NULL, -1 }};
static struct dict actionnames[] = {
{ "sighup", RCTL_ACTION_SIGHUP },
{ "sigint", RCTL_ACTION_SIGINT },
{ "sigquit", RCTL_ACTION_SIGQUIT },
{ "sigill", RCTL_ACTION_SIGILL },
{ "sigtrap", RCTL_ACTION_SIGTRAP },
{ "sigabrt", RCTL_ACTION_SIGABRT },
{ "sigemt", RCTL_ACTION_SIGEMT },
{ "sigfpe", RCTL_ACTION_SIGFPE },
{ "sigkill", RCTL_ACTION_SIGKILL },
{ "sigbus", RCTL_ACTION_SIGBUS },
{ "sigsegv", RCTL_ACTION_SIGSEGV },
{ "sigsys", RCTL_ACTION_SIGSYS },
{ "sigpipe", RCTL_ACTION_SIGPIPE },
{ "sigalrm", RCTL_ACTION_SIGALRM },
{ "sigterm", RCTL_ACTION_SIGTERM },
{ "sigurg", RCTL_ACTION_SIGURG },
{ "sigstop", RCTL_ACTION_SIGSTOP },
{ "sigtstp", RCTL_ACTION_SIGTSTP },
{ "sigchld", RCTL_ACTION_SIGCHLD },
{ "sigttin", RCTL_ACTION_SIGTTIN },
{ "sigttou", RCTL_ACTION_SIGTTOU },
{ "sigio", RCTL_ACTION_SIGIO },
{ "sigxcpu", RCTL_ACTION_SIGXCPU },
{ "sigxfsz", RCTL_ACTION_SIGXFSZ },
{ "sigvtalrm", RCTL_ACTION_SIGVTALRM },
{ "sigprof", RCTL_ACTION_SIGPROF },
{ "sigwinch", RCTL_ACTION_SIGWINCH },
{ "siginfo", RCTL_ACTION_SIGINFO },
{ "sigusr1", RCTL_ACTION_SIGUSR1 },
{ "sigusr2", RCTL_ACTION_SIGUSR2 },
{ "sigthr", RCTL_ACTION_SIGTHR },
{ "deny", RCTL_ACTION_DENY },
{ "log", RCTL_ACTION_LOG },
{ "devctl", RCTL_ACTION_DEVCTL },
{ NULL, -1 }};
static void rctl_init(void);
SYSINIT(rctl, SI_SUB_RACCT, SI_ORDER_FIRST, rctl_init, NULL);
static uma_zone_t rctl_rule_link_zone;
static uma_zone_t rctl_rule_zone;
static struct rwlock rctl_lock;
RW_SYSINIT(rctl_lock, &rctl_lock, "RCTL lock");
static int rctl_rule_fully_specified(const struct rctl_rule *rule);
static void rctl_rule_to_sbuf(struct sbuf *sb, const struct rctl_rule *rule);
MALLOC_DEFINE(M_RCTL, "rctl", "Resource Limits");
static const char *
rctl_subject_type_name(int subject)
{
int i;
for (i = 0; subjectnames[i].d_name != NULL; i++) {
if (subjectnames[i].d_value == subject)
return (subjectnames[i].d_name);
}
panic("rctl_subject_type_name: unknown subject type %d", subject);
}
static const char *
rctl_action_name(int action)
{
int i;
for (i = 0; actionnames[i].d_name != NULL; i++) {
if (actionnames[i].d_value == action)
return (actionnames[i].d_name);
}
panic("rctl_action_name: unknown action %d", action);
}
const char *
rctl_resource_name(int resource)
{
int i;
for (i = 0; resourcenames[i].d_name != NULL; i++) {
if (resourcenames[i].d_value == resource)
return (resourcenames[i].d_name);
}
panic("rctl_resource_name: unknown resource %d", resource);
}
/*
* Return the amount of resource that can be allocated by 'p' before
* hitting 'rule'.
*/
static int64_t
rctl_available_resource(const struct proc *p, const struct rctl_rule *rule)
{
int resource;
int64_t available = INT64_MAX;
struct ucred *cred = p->p_ucred;
rw_assert(&rctl_lock, RA_LOCKED);
resource = rule->rr_resource;
switch (rule->rr_per) {
case RCTL_SUBJECT_TYPE_PROCESS:
available = rule->rr_amount -
p->p_racct->r_resources[resource];
break;
case RCTL_SUBJECT_TYPE_USER:
available = rule->rr_amount -
cred->cr_ruidinfo->ui_racct->r_resources[resource];
break;
case RCTL_SUBJECT_TYPE_LOGINCLASS:
available = rule->rr_amount -
cred->cr_loginclass->lc_racct->r_resources[resource];
break;
case RCTL_SUBJECT_TYPE_JAIL:
available = rule->rr_amount -
cred->cr_prison->pr_prison_racct->prr_racct->
r_resources[resource];
break;
default:
panic("rctl_compute_available: unknown per %d",
rule->rr_per);
}
return (available);
}
/*
* Return non-zero if allocating 'amount' by proc 'p' would exceed
* resource limit specified by 'rule'.
*/
static int
rctl_would_exceed(const struct proc *p, const struct rctl_rule *rule,
int64_t amount)
{
int64_t available;
rw_assert(&rctl_lock, RA_LOCKED);
available = rctl_available_resource(p, rule);
if (available >= amount)
return (0);
return (1);
}
/*
* Check whether the proc 'p' can allocate 'amount' of 'resource' in addition
* to what it keeps allocated now. Returns non-zero if the allocation should
* be denied, 0 otherwise.
*/
int
rctl_enforce(struct proc *p, int resource, uint64_t amount)
{
struct rctl_rule *rule;
struct rctl_rule_link *link;
struct sbuf sb;
int should_deny = 0;
char *buf;
static int curtime = 0;
static struct timeval lasttime;
rw_rlock(&rctl_lock);
/*
* There may be more than one matching rule; go through all of them.
* Denial should be done last, after logging and sending signals.
*/
LIST_FOREACH(link, &p->p_racct->r_rule_links, rrl_next) {
rule = link->rrl_rule;
if (rule->rr_resource != resource)
continue;
if (!rctl_would_exceed(p, rule, amount)) {
link->rrl_exceeded = 0;
continue;
}
switch (rule->rr_action) {
case RCTL_ACTION_DENY:
should_deny = 1;
continue;
case RCTL_ACTION_LOG:
/*
* If rrl_exceeded != 0, it means we've already
* logged a warning for this process.
*/
if (link->rrl_exceeded != 0)
continue;
if (!ppsratecheck(&lasttime, &curtime, 10))
continue;
buf = malloc(RCTL_LOG_BUFSIZE, M_RCTL, M_NOWAIT);
if (buf == NULL) {
printf("rctl_enforce: out of memory\n");
continue;
}
sbuf_new(&sb, buf, RCTL_LOG_BUFSIZE, SBUF_FIXEDLEN);
rctl_rule_to_sbuf(&sb, rule);
sbuf_finish(&sb);
printf("rctl: rule \"%s\" matched by pid %d "
"(%s), uid %d, jail %s\n", sbuf_data(&sb),
p->p_pid, p->p_comm, p->p_ucred->cr_uid,
p->p_ucred->cr_prison->pr_prison_racct->prr_name);
sbuf_delete(&sb);
free(buf, M_RCTL);
link->rrl_exceeded = 1;
continue;
case RCTL_ACTION_DEVCTL:
if (link->rrl_exceeded != 0)
continue;
buf = malloc(RCTL_LOG_BUFSIZE, M_RCTL, M_NOWAIT);
if (buf == NULL) {
printf("rctl_enforce: out of memory\n");
continue;
}
sbuf_new(&sb, buf, RCTL_LOG_BUFSIZE, SBUF_FIXEDLEN);
sbuf_printf(&sb, "rule=");
rctl_rule_to_sbuf(&sb, rule);
sbuf_printf(&sb, " pid=%d ruid=%d jail=%s",
p->p_pid, p->p_ucred->cr_ruid,
p->p_ucred->cr_prison->pr_prison_racct->prr_name);
sbuf_finish(&sb);
devctl_notify_f("RCTL", "rule", "matched",
sbuf_data(&sb), M_NOWAIT);
sbuf_delete(&sb);
free(buf, M_RCTL);
link->rrl_exceeded = 1;
continue;
default:
if (link->rrl_exceeded != 0)
continue;
KASSERT(rule->rr_action > 0 &&
rule->rr_action <= RCTL_ACTION_SIGNAL_MAX,
("rctl_enforce: unknown action %d",
rule->rr_action));
/*
* We're supposed to send a signal, but the process
* is not fully initialized yet, probably because we
* got called from fork1(). For now just deny the
* allocation instead.
*/
if (p->p_state != PRS_NORMAL) {
should_deny = 1;
continue;
}
/*
* We're using the fact that RCTL_ACTION_SIG* values
* are equal to their counterparts from sys/signal.h.
*/
kern_psignal(p, rule->rr_action);
link->rrl_exceeded = 1;
continue;
}
}
rw_runlock(&rctl_lock);
if (should_deny) {
/*
* Return fake error code; the caller should change it
* into one proper for the situation - EFSIZ, ENOMEM etc.
*/
return (EDOOFUS);
}
return (0);
}
uint64_t
rctl_get_limit(struct proc *p, int resource)
{
struct rctl_rule *rule;
struct rctl_rule_link *link;
uint64_t amount = UINT64_MAX;
rw_rlock(&rctl_lock);
/*
* There may be more than one matching rule; go through all of them.
* Denial should be done last, after logging and sending signals.
*/
LIST_FOREACH(link, &p->p_racct->r_rule_links, rrl_next) {
rule = link->rrl_rule;
if (rule->rr_resource != resource)
continue;
if (rule->rr_action != RCTL_ACTION_DENY)
continue;
if (rule->rr_amount < amount)
amount = rule->rr_amount;
}
rw_runlock(&rctl_lock);
return (amount);
}
uint64_t
rctl_get_available(struct proc *p, int resource)
{
struct rctl_rule *rule;
struct rctl_rule_link *link;
int64_t available, minavailable, allocated;
minavailable = INT64_MAX;
rw_rlock(&rctl_lock);
/*
* There may be more than one matching rule; go through all of them.
* Denial should be done last, after logging and sending signals.
*/
LIST_FOREACH(link, &p->p_racct->r_rule_links, rrl_next) {
rule = link->rrl_rule;
if (rule->rr_resource != resource)
continue;
if (rule->rr_action != RCTL_ACTION_DENY)
continue;
available = rctl_available_resource(p, rule);
if (available < minavailable)
minavailable = available;
}
rw_runlock(&rctl_lock);
/*
* XXX: Think about this _hard_.
*/
allocated = p->p_racct->r_resources[resource];
if (minavailable < INT64_MAX - allocated)
minavailable += allocated;
if (minavailable < 0)
minavailable = 0;
return (minavailable);
}
static int
rctl_rule_matches(const struct rctl_rule *rule, const struct rctl_rule *filter)
{
if (filter->rr_subject_type != RCTL_SUBJECT_TYPE_UNDEFINED) {
if (rule->rr_subject_type != filter->rr_subject_type)
return (0);
switch (filter->rr_subject_type) {
case RCTL_SUBJECT_TYPE_PROCESS:
if (filter->rr_subject.rs_proc != NULL &&
rule->rr_subject.rs_proc !=
filter->rr_subject.rs_proc)
return (0);
break;
case RCTL_SUBJECT_TYPE_USER:
if (filter->rr_subject.rs_uip != NULL &&
rule->rr_subject.rs_uip !=
filter->rr_subject.rs_uip)
return (0);
break;
case RCTL_SUBJECT_TYPE_LOGINCLASS:
if (filter->rr_subject.rs_loginclass != NULL &&
rule->rr_subject.rs_loginclass !=
filter->rr_subject.rs_loginclass)
return (0);
break;
case RCTL_SUBJECT_TYPE_JAIL:
if (filter->rr_subject.rs_prison_racct != NULL &&
rule->rr_subject.rs_prison_racct !=
filter->rr_subject.rs_prison_racct)
return (0);
break;
default:
panic("rctl_rule_matches: unknown subject type %d",
filter->rr_subject_type);
}
}
if (filter->rr_resource != RACCT_UNDEFINED) {
if (rule->rr_resource != filter->rr_resource)
return (0);
}
if (filter->rr_action != RCTL_ACTION_UNDEFINED) {
if (rule->rr_action != filter->rr_action)
return (0);
}
if (filter->rr_amount != RCTL_AMOUNT_UNDEFINED) {
if (rule->rr_amount != filter->rr_amount)
return (0);
}
if (filter->rr_per != RCTL_SUBJECT_TYPE_UNDEFINED) {
if (rule->rr_per != filter->rr_per)
return (0);
}
return (1);
}
static int
str2value(const char *str, int *value, struct dict *table)
{
int i;
if (value == NULL)
return (EINVAL);
for (i = 0; table[i].d_name != NULL; i++) {
if (strcasecmp(table[i].d_name, str) == 0) {
*value = table[i].d_value;
return (0);
}
}
return (EINVAL);
}
static int
str2id(const char *str, id_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 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);
}
/*
* Connect the rule to the racct, increasing refcount for the rule.
*/
static void
rctl_racct_add_rule(struct racct *racct, struct rctl_rule *rule)
{
struct rctl_rule_link *link;
KASSERT(rctl_rule_fully_specified(rule), ("rule not fully specified"));
rctl_rule_acquire(rule);
link = uma_zalloc(rctl_rule_link_zone, M_WAITOK);
link->rrl_rule = rule;
link->rrl_exceeded = 0;
rw_wlock(&rctl_lock);
LIST_INSERT_HEAD(&racct->r_rule_links, link, rrl_next);
rw_wunlock(&rctl_lock);
}
static int
rctl_racct_add_rule_locked(struct racct *racct, struct rctl_rule *rule)
{
struct rctl_rule_link *link;
KASSERT(rctl_rule_fully_specified(rule), ("rule not fully specified"));
rw_assert(&rctl_lock, RA_WLOCKED);
link = uma_zalloc(rctl_rule_link_zone, M_NOWAIT);
if (link == NULL)
return (ENOMEM);
rctl_rule_acquire(rule);
link->rrl_rule = rule;
link->rrl_exceeded = 0;
LIST_INSERT_HEAD(&racct->r_rule_links, link, rrl_next);
return (0);
}
/*
* Remove limits for a rules matching the filter and release
* the refcounts for the rules, possibly freeing them. Returns
* the number of limit structures removed.
*/
static int
rctl_racct_remove_rules(struct racct *racct,
const struct rctl_rule *filter)
{
int removed = 0;
struct rctl_rule_link *link, *linktmp;
rw_assert(&rctl_lock, RA_WLOCKED);
LIST_FOREACH_SAFE(link, &racct->r_rule_links, rrl_next, linktmp) {
if (!rctl_rule_matches(link->rrl_rule, filter))
continue;
LIST_REMOVE(link, rrl_next);
rctl_rule_release(link->rrl_rule);
uma_zfree(rctl_rule_link_zone, link);
removed++;
}
return (removed);
}
static void
rctl_rule_acquire_subject(struct rctl_rule *rule)
{
switch (rule->rr_subject_type) {
case RCTL_SUBJECT_TYPE_UNDEFINED:
case RCTL_SUBJECT_TYPE_PROCESS:
break;
case RCTL_SUBJECT_TYPE_JAIL:
if (rule->rr_subject.rs_prison_racct != NULL)
prison_racct_hold(rule->rr_subject.rs_prison_racct);
break;
case RCTL_SUBJECT_TYPE_USER:
if (rule->rr_subject.rs_uip != NULL)
uihold(rule->rr_subject.rs_uip);
break;
case RCTL_SUBJECT_TYPE_LOGINCLASS:
if (rule->rr_subject.rs_loginclass != NULL)
loginclass_hold(rule->rr_subject.rs_loginclass);
break;
default:
panic("rctl_rule_acquire_subject: unknown subject type %d",
rule->rr_subject_type);
}
}
static void
rctl_rule_release_subject(struct rctl_rule *rule)
{
switch (rule->rr_subject_type) {
case RCTL_SUBJECT_TYPE_UNDEFINED:
case RCTL_SUBJECT_TYPE_PROCESS:
break;
case RCTL_SUBJECT_TYPE_JAIL:
if (rule->rr_subject.rs_prison_racct != NULL)
prison_racct_free(rule->rr_subject.rs_prison_racct);
break;
case RCTL_SUBJECT_TYPE_USER:
if (rule->rr_subject.rs_uip != NULL)
uifree(rule->rr_subject.rs_uip);
break;
case RCTL_SUBJECT_TYPE_LOGINCLASS:
if (rule->rr_subject.rs_loginclass != NULL)
loginclass_free(rule->rr_subject.rs_loginclass);
break;
default:
panic("rctl_rule_release_subject: unknown subject type %d",
rule->rr_subject_type);
}
}
struct rctl_rule *
rctl_rule_alloc(int flags)
{
struct rctl_rule *rule;
rule = uma_zalloc(rctl_rule_zone, flags);
if (rule == NULL)
return (NULL);
rule->rr_subject_type = RCTL_SUBJECT_TYPE_UNDEFINED;
rule->rr_subject.rs_proc = NULL;
rule->rr_subject.rs_uip = NULL;
rule->rr_subject.rs_loginclass = NULL;
rule->rr_subject.rs_prison_racct = NULL;
rule->rr_per = RCTL_SUBJECT_TYPE_UNDEFINED;
rule->rr_resource = RACCT_UNDEFINED;
rule->rr_action = RCTL_ACTION_UNDEFINED;
rule->rr_amount = RCTL_AMOUNT_UNDEFINED;
refcount_init(&rule->rr_refcount, 1);
return (rule);
}
struct rctl_rule *
rctl_rule_duplicate(const struct rctl_rule *rule, int flags)
{
struct rctl_rule *copy;
copy = uma_zalloc(rctl_rule_zone, flags);
if (copy == NULL)
return (NULL);
copy->rr_subject_type = rule->rr_subject_type;
copy->rr_subject.rs_proc = rule->rr_subject.rs_proc;
copy->rr_subject.rs_uip = rule->rr_subject.rs_uip;
copy->rr_subject.rs_loginclass = rule->rr_subject.rs_loginclass;
copy->rr_subject.rs_prison_racct = rule->rr_subject.rs_prison_racct;
copy->rr_per = rule->rr_per;
copy->rr_resource = rule->rr_resource;
copy->rr_action = rule->rr_action;
copy->rr_amount = rule->rr_amount;
refcount_init(&copy->rr_refcount, 1);
rctl_rule_acquire_subject(copy);
return (copy);
}
void
rctl_rule_acquire(struct rctl_rule *rule)
{
KASSERT(rule->rr_refcount > 0, ("rule->rr_refcount <= 0"));
refcount_acquire(&rule->rr_refcount);
}
static void
rctl_rule_free(void *context, int pending)
{
struct rctl_rule *rule;
rule = (struct rctl_rule *)context;
KASSERT(rule->rr_refcount == 0, ("rule->rr_refcount != 0"));
/*
* We don't need locking here; rule is guaranteed to be inaccessible.
*/
rctl_rule_release_subject(rule);
uma_zfree(rctl_rule_zone, rule);
}
void
rctl_rule_release(struct rctl_rule *rule)
{
KASSERT(rule->rr_refcount > 0, ("rule->rr_refcount <= 0"));
if (refcount_release(&rule->rr_refcount)) {
/*
* rctl_rule_release() is often called when iterating
* over all the uidinfo structures in the system,
* holding uihashtbl_lock. Since rctl_rule_free()
* might end up calling uifree(), this would lead
* to lock recursion. Use taskqueue to avoid this.
*/
TASK_INIT(&rule->rr_task, 0, rctl_rule_free, rule);
taskqueue_enqueue(taskqueue_thread, &rule->rr_task);
}
}
static int
rctl_rule_fully_specified(const struct rctl_rule *rule)
{
switch (rule->rr_subject_type) {
case RCTL_SUBJECT_TYPE_UNDEFINED:
return (0);
case RCTL_SUBJECT_TYPE_PROCESS:
if (rule->rr_subject.rs_proc == NULL)
return (0);
break;
case RCTL_SUBJECT_TYPE_USER:
if (rule->rr_subject.rs_uip == NULL)
return (0);
break;
case RCTL_SUBJECT_TYPE_LOGINCLASS:
if (rule->rr_subject.rs_loginclass == NULL)
return (0);
break;
case RCTL_SUBJECT_TYPE_JAIL:
if (rule->rr_subject.rs_prison_racct == NULL)
return (0);
break;
default:
panic("rctl_rule_fully_specified: unknown subject type %d",
rule->rr_subject_type);
}
if (rule->rr_resource == RACCT_UNDEFINED)
return (0);
if (rule->rr_action == RCTL_ACTION_UNDEFINED)
return (0);
if (rule->rr_amount == RCTL_AMOUNT_UNDEFINED)
return (0);
if (rule->rr_per == RCTL_SUBJECT_TYPE_UNDEFINED)
return (0);
return (1);
}
static int
rctl_string_to_rule(char *rulestr, struct rctl_rule **rulep)
{
int error = 0;
char *subjectstr, *subject_idstr, *resourcestr, *actionstr,
*amountstr, *perstr;
struct rctl_rule *rule;
id_t id;
rule = rctl_rule_alloc(M_WAITOK);
subjectstr = strsep(&rulestr, ":");
subject_idstr = strsep(&rulestr, ":");
resourcestr = strsep(&rulestr, ":");
actionstr = strsep(&rulestr, "=/");
amountstr = strsep(&rulestr, "/");
perstr = rulestr;
if (subjectstr == NULL || subjectstr[0] == '\0')
rule->rr_subject_type = RCTL_SUBJECT_TYPE_UNDEFINED;
else {
error = str2value(subjectstr, &rule->rr_subject_type, subjectnames);
if (error != 0)
goto out;
}
if (subject_idstr == NULL || subject_idstr[0] == '\0') {
rule->rr_subject.rs_proc = NULL;
rule->rr_subject.rs_uip = NULL;
rule->rr_subject.rs_loginclass = NULL;
rule->rr_subject.rs_prison_racct = NULL;
} else {
switch (rule->rr_subject_type) {
case RCTL_SUBJECT_TYPE_UNDEFINED:
error = EINVAL;
goto out;
case RCTL_SUBJECT_TYPE_PROCESS:
error = str2id(subject_idstr, &id);
if (error != 0)
goto out;
sx_assert(&allproc_lock, SA_LOCKED);
rule->rr_subject.rs_proc = pfind(id);
if (rule->rr_subject.rs_proc == NULL) {
error = ESRCH;
goto out;
}
PROC_UNLOCK(rule->rr_subject.rs_proc);
break;
case RCTL_SUBJECT_TYPE_USER:
error = str2id(subject_idstr, &id);
if (error != 0)
goto out;
rule->rr_subject.rs_uip = uifind(id);
break;
case RCTL_SUBJECT_TYPE_LOGINCLASS:
rule->rr_subject.rs_loginclass =
loginclass_find(subject_idstr);
if (rule->rr_subject.rs_loginclass == NULL) {
error = ENAMETOOLONG;
goto out;
}
break;
case RCTL_SUBJECT_TYPE_JAIL:
rule->rr_subject.rs_prison_racct =
prison_racct_find(subject_idstr);
if (rule->rr_subject.rs_prison_racct == NULL) {
error = ENAMETOOLONG;
goto out;
}
break;
default:
panic("rctl_string_to_rule: unknown subject type %d",
rule->rr_subject_type);
}
}
if (resourcestr == NULL || resourcestr[0] == '\0')
rule->rr_resource = RACCT_UNDEFINED;
else {
error = str2value(resourcestr, &rule->rr_resource,
resourcenames);
if (error != 0)
goto out;
}
if (actionstr == NULL || actionstr[0] == '\0')
rule->rr_action = RCTL_ACTION_UNDEFINED;
else {
error = str2value(actionstr, &rule->rr_action, actionnames);
if (error != 0)
goto out;
}
if (amountstr == NULL || amountstr[0] == '\0')
rule->rr_amount = RCTL_AMOUNT_UNDEFINED;
else {
error = str2int64(amountstr, &rule->rr_amount);
if (error != 0)
goto out;
if (RACCT_IS_IN_MILLIONS(rule->rr_resource))
rule->rr_amount *= 1000000;
}
if (perstr == NULL || perstr[0] == '\0')
rule->rr_per = RCTL_SUBJECT_TYPE_UNDEFINED;
else {
error = str2value(perstr, &rule->rr_per, subjectnames);
if (error != 0)
goto out;
}
out:
if (error == 0)
*rulep = rule;
else
rctl_rule_release(rule);
return (error);
}
/*
* Link a rule with all the subjects it applies to.
*/
int
rctl_rule_add(struct rctl_rule *rule)
{
struct proc *p;
struct ucred *cred;
struct uidinfo *uip;
struct prison *pr;
struct prison_racct *prr;
struct loginclass *lc;
struct rctl_rule *rule2;
int match;
KASSERT(rctl_rule_fully_specified(rule), ("rule not fully specified"));
/*
* Some rules just don't make sense. Note that the one below
* cannot be rewritten using RACCT_IS_DENIABLE(); the RACCT_PCTCPU,
* for example, is not deniable in the racct sense, but the
* limit is enforced in a different way, so "deny" rules for %CPU
* do make sense.
*/
if (rule->rr_action == RCTL_ACTION_DENY &&
(rule->rr_resource == RACCT_CPU ||
rule->rr_resource == RACCT_WALLCLOCK))
return (EOPNOTSUPP);
if (rule->rr_per == RCTL_SUBJECT_TYPE_PROCESS &&
RACCT_IS_SLOPPY(rule->rr_resource))
return (EOPNOTSUPP);
/*
* Make sure there are no duplicated rules. Also, for the "deny"
* rules, remove ones differing only by "amount".
*/
if (rule->rr_action == RCTL_ACTION_DENY) {
rule2 = rctl_rule_duplicate(rule, M_WAITOK);
rule2->rr_amount = RCTL_AMOUNT_UNDEFINED;
rctl_rule_remove(rule2);
rctl_rule_release(rule2);
} else
rctl_rule_remove(rule);
switch (rule->rr_subject_type) {
case RCTL_SUBJECT_TYPE_PROCESS:
p = rule->rr_subject.rs_proc;
KASSERT(p != NULL, ("rctl_rule_add: NULL proc"));
/*
* No resource limits for system processes.
*/
if (p->p_flag & P_SYSTEM)
return (EPERM);
rctl_racct_add_rule(p->p_racct, rule);
/*
* In case of per-process rule, we don't have anything more
* to do.
*/
return (0);
case RCTL_SUBJECT_TYPE_USER:
uip = rule->rr_subject.rs_uip;
KASSERT(uip != NULL, ("rctl_rule_add: NULL uip"));
rctl_racct_add_rule(uip->ui_racct, rule);
break;
case RCTL_SUBJECT_TYPE_LOGINCLASS:
lc = rule->rr_subject.rs_loginclass;
KASSERT(lc != NULL, ("rctl_rule_add: NULL loginclass"));
rctl_racct_add_rule(lc->lc_racct, rule);
break;
case RCTL_SUBJECT_TYPE_JAIL:
prr = rule->rr_subject.rs_prison_racct;
KASSERT(prr != NULL, ("rctl_rule_add: NULL pr"));
rctl_racct_add_rule(prr->prr_racct, rule);
break;
default:
panic("rctl_rule_add: unknown subject type %d",
rule->rr_subject_type);
}
/*
* Now go through all the processes and add the new rule to the ones
* it applies to.
*/
sx_assert(&allproc_lock, SA_LOCKED);
FOREACH_PROC_IN_SYSTEM(p) {
if (p->p_flag & P_SYSTEM)
continue;
cred = p->p_ucred;
switch (rule->rr_subject_type) {
case RCTL_SUBJECT_TYPE_USER:
if (cred->cr_uidinfo == rule->rr_subject.rs_uip ||
cred->cr_ruidinfo == rule->rr_subject.rs_uip)
break;
continue;
case RCTL_SUBJECT_TYPE_LOGINCLASS:
if (cred->cr_loginclass == rule->rr_subject.rs_loginclass)
break;
continue;
case RCTL_SUBJECT_TYPE_JAIL:
match = 0;
for (pr = cred->cr_prison; pr != NULL; pr = pr->pr_parent) {
if (pr->pr_prison_racct == rule->rr_subject.rs_prison_racct) {
match = 1;
break;
}
}
if (match)
break;
continue;
default:
panic("rctl_rule_add: unknown subject type %d",
rule->rr_subject_type);
}
rctl_racct_add_rule(p->p_racct, rule);
}
return (0);
}
static void
rctl_rule_remove_callback(struct racct *racct, void *arg2, void *arg3)
{
struct rctl_rule *filter = (struct rctl_rule *)arg2;
int found = 0;
rw_wlock(&rctl_lock);
found += rctl_racct_remove_rules(racct, filter);
rw_wunlock(&rctl_lock);
*((int *)arg3) += found;
}
/*
* Remove all rules that match the filter.
*/
int
rctl_rule_remove(struct rctl_rule *filter)
{
int found = 0;
struct proc *p;
if (filter->rr_subject_type == RCTL_SUBJECT_TYPE_PROCESS &&
filter->rr_subject.rs_proc != NULL) {
p = filter->rr_subject.rs_proc;
rw_wlock(&rctl_lock);
found = rctl_racct_remove_rules(p->p_racct, filter);
rw_wunlock(&rctl_lock);
if (found)
return (0);
return (ESRCH);
}
loginclass_racct_foreach(rctl_rule_remove_callback, filter,
(void *)&found);
ui_racct_foreach(rctl_rule_remove_callback, filter,
(void *)&found);
prison_racct_foreach(rctl_rule_remove_callback, filter,
(void *)&found);
sx_assert(&allproc_lock, SA_LOCKED);
rw_wlock(&rctl_lock);
FOREACH_PROC_IN_SYSTEM(p) {
found += rctl_racct_remove_rules(p->p_racct, filter);
}
rw_wunlock(&rctl_lock);
if (found)
return (0);
return (ESRCH);
}
/*
* Appends a rule to the sbuf.
*/
static void
rctl_rule_to_sbuf(struct sbuf *sb, const struct rctl_rule *rule)
{
int64_t amount;
sbuf_printf(sb, "%s:", rctl_subject_type_name(rule->rr_subject_type));
switch (rule->rr_subject_type) {
case RCTL_SUBJECT_TYPE_PROCESS:
if (rule->rr_subject.rs_proc == NULL)
sbuf_printf(sb, ":");
else
sbuf_printf(sb, "%d:",
rule->rr_subject.rs_proc->p_pid);
break;
case RCTL_SUBJECT_TYPE_USER:
if (rule->rr_subject.rs_uip == NULL)
sbuf_printf(sb, ":");
else
sbuf_printf(sb, "%d:",
rule->rr_subject.rs_uip->ui_uid);
break;
case RCTL_SUBJECT_TYPE_LOGINCLASS:
if (rule->rr_subject.rs_loginclass == NULL)
sbuf_printf(sb, ":");
else
sbuf_printf(sb, "%s:",
rule->rr_subject.rs_loginclass->lc_name);
break;
case RCTL_SUBJECT_TYPE_JAIL:
if (rule->rr_subject.rs_prison_racct == NULL)
sbuf_printf(sb, ":");
else
sbuf_printf(sb, "%s:",
rule->rr_subject.rs_prison_racct->prr_name);
break;
default:
panic("rctl_rule_to_sbuf: unknown subject type %d",
rule->rr_subject_type);
}
amount = rule->rr_amount;
if (amount != RCTL_AMOUNT_UNDEFINED &&
RACCT_IS_IN_MILLIONS(rule->rr_resource))
amount /= 1000000;
sbuf_printf(sb, "%s:%s=%jd",
rctl_resource_name(rule->rr_resource),
rctl_action_name(rule->rr_action),
amount);
if (rule->rr_per != rule->rr_subject_type)
sbuf_printf(sb, "/%s", rctl_subject_type_name(rule->rr_per));
}
/*
* Routine used by RCTL syscalls to read in input string.
*/
static int
rctl_read_inbuf(char **inputstr, const char *inbufp, size_t inbuflen)
{
int error;
char *str;
if (inbuflen <= 0)
return (EINVAL);
str = malloc(inbuflen + 1, M_RCTL, M_WAITOK);
error = copyinstr(inbufp, str, inbuflen, NULL);
if (error != 0) {
free(str, M_RCTL);
return (error);
}
*inputstr = str;
return (0);
}
/*
* Routine used by RCTL syscalls to write out output string.
*/
static int
rctl_write_outbuf(struct sbuf *outputsbuf, char *outbufp, size_t outbuflen)
{
int error;
if (outputsbuf == NULL)
return (0);
sbuf_finish(outputsbuf);
if (outbuflen < sbuf_len(outputsbuf) + 1) {
sbuf_delete(outputsbuf);
return (ERANGE);
}
error = copyout(sbuf_data(outputsbuf), outbufp,
sbuf_len(outputsbuf) + 1);
sbuf_delete(outputsbuf);
return (error);
}
static struct sbuf *
rctl_racct_to_sbuf(struct racct *racct, int sloppy)
{
int i;
int64_t amount;
struct sbuf *sb;
sb = sbuf_new_auto();
for (i = 0; i <= RACCT_MAX; i++) {
if (sloppy == 0 && RACCT_IS_SLOPPY(i))
continue;
amount = racct->r_resources[i];
if (RACCT_IS_IN_MILLIONS(i))
amount /= 1000000;
sbuf_printf(sb, "%s=%jd,", rctl_resource_name(i), amount);
}
sbuf_setpos(sb, sbuf_len(sb) - 1);
return (sb);
}
int
sys_rctl_get_racct(struct thread *td, struct rctl_get_racct_args *uap)
{
int error;
char *inputstr;
struct rctl_rule *filter;
struct sbuf *outputsbuf = NULL;
struct proc *p;
struct uidinfo *uip;
struct loginclass *lc;
struct prison_racct *prr;
error = priv_check(td, PRIV_RCTL_GET_RACCT);
if (error != 0)
return (error);
error = rctl_read_inbuf(&inputstr, uap->inbufp, uap->inbuflen);
if (error != 0)
return (error);
sx_slock(&allproc_lock);
error = rctl_string_to_rule(inputstr, &filter);
free(inputstr, M_RCTL);
if (error != 0) {
sx_sunlock(&allproc_lock);
return (error);
}
switch (filter->rr_subject_type) {
case RCTL_SUBJECT_TYPE_PROCESS:
p = filter->rr_subject.rs_proc;
if (p == NULL) {
error = EINVAL;
goto out;
}
if (p->p_flag & P_SYSTEM) {
error = EINVAL;
goto out;
}
outputsbuf = rctl_racct_to_sbuf(p->p_racct, 0);
break;
case RCTL_SUBJECT_TYPE_USER:
uip = filter->rr_subject.rs_uip;
if (uip == NULL) {
error = EINVAL;
goto out;
}
outputsbuf = rctl_racct_to_sbuf(uip->ui_racct, 1);
break;
case RCTL_SUBJECT_TYPE_LOGINCLASS:
lc = filter->rr_subject.rs_loginclass;
if (lc == NULL) {
error = EINVAL;
goto out;
}
outputsbuf = rctl_racct_to_sbuf(lc->lc_racct, 1);
break;
case RCTL_SUBJECT_TYPE_JAIL:
prr = filter->rr_subject.rs_prison_racct;
if (prr == NULL) {
error = EINVAL;
goto out;
}
outputsbuf = rctl_racct_to_sbuf(prr->prr_racct, 1);
break;
default:
error = EINVAL;
}
out:
rctl_rule_release(filter);
sx_sunlock(&allproc_lock);
if (error != 0)
return (error);
error = rctl_write_outbuf(outputsbuf, uap->outbufp, uap->outbuflen);
return (error);
}
static void
rctl_get_rules_callback(struct racct *racct, void *arg2, void *arg3)
{
struct rctl_rule *filter = (struct rctl_rule *)arg2;
struct rctl_rule_link *link;
struct sbuf *sb = (struct sbuf *)arg3;
rw_rlock(&rctl_lock);
LIST_FOREACH(link, &racct->r_rule_links, rrl_next) {
if (!rctl_rule_matches(link->rrl_rule, filter))
continue;
rctl_rule_to_sbuf(sb, link->rrl_rule);
sbuf_printf(sb, ",");
}
rw_runlock(&rctl_lock);
}
int
sys_rctl_get_rules(struct thread *td, struct rctl_get_rules_args *uap)
{
int error;
size_t bufsize = RCTL_DEFAULT_BUFSIZE;
char *inputstr, *buf;
struct sbuf *sb;
struct rctl_rule *filter;
struct rctl_rule_link *link;
struct proc *p;
error = priv_check(td, PRIV_RCTL_GET_RULES);
if (error != 0)
return (error);
error = rctl_read_inbuf(&inputstr, uap->inbufp, uap->inbuflen);
if (error != 0)
return (error);
sx_slock(&allproc_lock);
error = rctl_string_to_rule(inputstr, &filter);
free(inputstr, M_RCTL);
if (error != 0) {
sx_sunlock(&allproc_lock);
return (error);
}
again:
buf = malloc(bufsize, M_RCTL, M_WAITOK);
sb = sbuf_new(NULL, buf, bufsize, SBUF_FIXEDLEN);
KASSERT(sb != NULL, ("sbuf_new failed"));
sx_assert(&allproc_lock, SA_LOCKED);
FOREACH_PROC_IN_SYSTEM(p) {
rw_rlock(&rctl_lock);
LIST_FOREACH(link, &p->p_racct->r_rule_links, rrl_next) {
/*
* Non-process rules will be added to the buffer later.
* Adding them here would result in duplicated output.
*/
if (link->rrl_rule->rr_subject_type !=
RCTL_SUBJECT_TYPE_PROCESS)
continue;
if (!rctl_rule_matches(link->rrl_rule, filter))
continue;
rctl_rule_to_sbuf(sb, link->rrl_rule);
sbuf_printf(sb, ",");
}
rw_runlock(&rctl_lock);
}
loginclass_racct_foreach(rctl_get_rules_callback, filter, sb);
ui_racct_foreach(rctl_get_rules_callback, filter, sb);
prison_racct_foreach(rctl_get_rules_callback, filter, sb);
if (sbuf_error(sb) == ENOMEM) {
sbuf_delete(sb);
free(buf, M_RCTL);
bufsize *= 4;
goto again;
}
/*
* Remove trailing ",".
*/
if (sbuf_len(sb) > 0)
sbuf_setpos(sb, sbuf_len(sb) - 1);
error = rctl_write_outbuf(sb, uap->outbufp, uap->outbuflen);
rctl_rule_release(filter);
sx_sunlock(&allproc_lock);
free(buf, M_RCTL);
return (error);
}
int
sys_rctl_get_limits(struct thread *td, struct rctl_get_limits_args *uap)
{
int error;
size_t bufsize = RCTL_DEFAULT_BUFSIZE;
char *inputstr, *buf;
struct sbuf *sb;
struct rctl_rule *filter;
struct rctl_rule_link *link;
error = priv_check(td, PRIV_RCTL_GET_LIMITS);
if (error != 0)
return (error);
error = rctl_read_inbuf(&inputstr, uap->inbufp, uap->inbuflen);
if (error != 0)
return (error);
sx_slock(&allproc_lock);
error = rctl_string_to_rule(inputstr, &filter);
free(inputstr, M_RCTL);
if (error != 0) {
sx_sunlock(&allproc_lock);
return (error);
}
if (filter->rr_subject_type == RCTL_SUBJECT_TYPE_UNDEFINED) {
rctl_rule_release(filter);
sx_sunlock(&allproc_lock);
return (EINVAL);
}
if (filter->rr_subject_type != RCTL_SUBJECT_TYPE_PROCESS) {
rctl_rule_release(filter);
sx_sunlock(&allproc_lock);
return (EOPNOTSUPP);
}
if (filter->rr_subject.rs_proc == NULL) {
rctl_rule_release(filter);
sx_sunlock(&allproc_lock);
return (EINVAL);
}
again:
buf = malloc(bufsize, M_RCTL, M_WAITOK);
sb = sbuf_new(NULL, buf, bufsize, SBUF_FIXEDLEN);
KASSERT(sb != NULL, ("sbuf_new failed"));
rw_rlock(&rctl_lock);
LIST_FOREACH(link, &filter->rr_subject.rs_proc->p_racct->r_rule_links,
rrl_next) {
rctl_rule_to_sbuf(sb, link->rrl_rule);
sbuf_printf(sb, ",");
}
rw_runlock(&rctl_lock);
if (sbuf_error(sb) == ENOMEM) {
sbuf_delete(sb);
free(buf, M_RCTL);
bufsize *= 4;
goto again;
}
/*
* Remove trailing ",".
*/
if (sbuf_len(sb) > 0)
sbuf_setpos(sb, sbuf_len(sb) - 1);
error = rctl_write_outbuf(sb, uap->outbufp, uap->outbuflen);
rctl_rule_release(filter);
sx_sunlock(&allproc_lock);
free(buf, M_RCTL);
return (error);
}
int
sys_rctl_add_rule(struct thread *td, struct rctl_add_rule_args *uap)
{
int error;
struct rctl_rule *rule;
char *inputstr;
error = priv_check(td, PRIV_RCTL_ADD_RULE);
if (error != 0)
return (error);
error = rctl_read_inbuf(&inputstr, uap->inbufp, uap->inbuflen);
if (error != 0)
return (error);
sx_slock(&allproc_lock);
error = rctl_string_to_rule(inputstr, &rule);
free(inputstr, M_RCTL);
if (error != 0) {
sx_sunlock(&allproc_lock);
return (error);
}
/*
* The 'per' part of a rule is optional.
*/
if (rule->rr_per == RCTL_SUBJECT_TYPE_UNDEFINED &&
rule->rr_subject_type != RCTL_SUBJECT_TYPE_UNDEFINED)
rule->rr_per = rule->rr_subject_type;
if (!rctl_rule_fully_specified(rule)) {
error = EINVAL;
goto out;
}
error = rctl_rule_add(rule);
out:
rctl_rule_release(rule);
sx_sunlock(&allproc_lock);
return (error);
}
int
sys_rctl_remove_rule(struct thread *td, struct rctl_remove_rule_args *uap)
{
int error;
struct rctl_rule *filter;
char *inputstr;
error = priv_check(td, PRIV_RCTL_REMOVE_RULE);
if (error != 0)
return (error);
error = rctl_read_inbuf(&inputstr, uap->inbufp, uap->inbuflen);
if (error != 0)
return (error);
sx_slock(&allproc_lock);
error = rctl_string_to_rule(inputstr, &filter);
free(inputstr, M_RCTL);
if (error != 0) {
sx_sunlock(&allproc_lock);
return (error);
}
error = rctl_rule_remove(filter);
rctl_rule_release(filter);
sx_sunlock(&allproc_lock);
return (error);
}
/*
* Update RCTL rule list after credential change.
*/
void
rctl_proc_ucred_changed(struct proc *p, struct ucred *newcred)
{
int rulecnt, i;
struct rctl_rule_link *link, *newlink;
struct uidinfo *newuip;
struct loginclass *newlc;
struct prison_racct *newprr;
LIST_HEAD(, rctl_rule_link) newrules;
newuip = newcred->cr_ruidinfo;
newlc = newcred->cr_loginclass;
newprr = newcred->cr_prison->pr_prison_racct;
LIST_INIT(&newrules);
again:
/*
* First, count the rules that apply to the process with new
* credentials.
*/
rulecnt = 0;
rw_rlock(&rctl_lock);
LIST_FOREACH(link, &p->p_racct->r_rule_links, rrl_next) {
if (link->rrl_rule->rr_subject_type ==
RCTL_SUBJECT_TYPE_PROCESS)
rulecnt++;
}
LIST_FOREACH(link, &newuip->ui_racct->r_rule_links, rrl_next)
rulecnt++;
LIST_FOREACH(link, &newlc->lc_racct->r_rule_links, rrl_next)
rulecnt++;
LIST_FOREACH(link, &newprr->prr_racct->r_rule_links, rrl_next)
rulecnt++;
rw_runlock(&rctl_lock);
/*
* Create temporary list. We've dropped the rctl_lock in order
* to use M_WAITOK.
*/
for (i = 0; i < rulecnt; i++) {
newlink = uma_zalloc(rctl_rule_link_zone, M_WAITOK);
newlink->rrl_rule = NULL;
LIST_INSERT_HEAD(&newrules, newlink, rrl_next);
}
newlink = LIST_FIRST(&newrules);
/*
* Assign rules to the newly allocated list entries.
*/
rw_wlock(&rctl_lock);
LIST_FOREACH(link, &p->p_racct->r_rule_links, rrl_next) {
if (link->rrl_rule->rr_subject_type ==
RCTL_SUBJECT_TYPE_PROCESS) {
if (newlink == NULL)
goto goaround;
rctl_rule_acquire(link->rrl_rule);
newlink->rrl_rule = link->rrl_rule;
newlink = LIST_NEXT(newlink, rrl_next);
rulecnt--;
}
}
LIST_FOREACH(link, &newuip->ui_racct->r_rule_links, rrl_next) {
if (newlink == NULL)
goto goaround;
rctl_rule_acquire(link->rrl_rule);
newlink->rrl_rule = link->rrl_rule;
newlink = LIST_NEXT(newlink, rrl_next);
rulecnt--;
}
LIST_FOREACH(link, &newlc->lc_racct->r_rule_links, rrl_next) {
if (newlink == NULL)
goto goaround;
rctl_rule_acquire(link->rrl_rule);
newlink->rrl_rule = link->rrl_rule;
newlink = LIST_NEXT(newlink, rrl_next);
rulecnt--;
}
LIST_FOREACH(link, &newprr->prr_racct->r_rule_links, rrl_next) {
if (newlink == NULL)
goto goaround;
rctl_rule_acquire(link->rrl_rule);
newlink->rrl_rule = link->rrl_rule;
newlink = LIST_NEXT(newlink, rrl_next);
rulecnt--;
}
if (rulecnt == 0) {
/*
* Free the old rule list.
*/
while (!LIST_EMPTY(&p->p_racct->r_rule_links)) {
link = LIST_FIRST(&p->p_racct->r_rule_links);
LIST_REMOVE(link, rrl_next);
rctl_rule_release(link->rrl_rule);
uma_zfree(rctl_rule_link_zone, link);
}
/*
* Replace lists and we're done.
*
* XXX: Is there any way to switch list heads instead
* of iterating here?
*/
while (!LIST_EMPTY(&newrules)) {
newlink = LIST_FIRST(&newrules);
LIST_REMOVE(newlink, rrl_next);
LIST_INSERT_HEAD(&p->p_racct->r_rule_links,
newlink, rrl_next);
}
rw_wunlock(&rctl_lock);
return;
}
goaround:
rw_wunlock(&rctl_lock);
/*
* Rule list changed while we were not holding the rctl_lock.
* Free the new list and try again.
*/
while (!LIST_EMPTY(&newrules)) {
newlink = LIST_FIRST(&newrules);
LIST_REMOVE(newlink, rrl_next);
if (newlink->rrl_rule != NULL)
rctl_rule_release(newlink->rrl_rule);
uma_zfree(rctl_rule_link_zone, newlink);
}
goto again;
}
/*
* Assign RCTL rules to the newly created process.
*/
int
rctl_proc_fork(struct proc *parent, struct proc *child)
{
int error;
struct rctl_rule_link *link;
struct rctl_rule *rule;
LIST_INIT(&child->p_racct->r_rule_links);
/*
* No limits for kernel processes.
*/
if (child->p_flag & P_SYSTEM)
return (0);
/*
* Nothing to inherit from P_SYSTEM parents.
*/
if (parent->p_racct == NULL) {
KASSERT(parent->p_flag & P_SYSTEM,
("non-system process without racct; p = %p", parent));
return (0);
}
rw_wlock(&rctl_lock);
/*
* Go through limits applicable to the parent and assign them
* to the child. Rules with 'process' subject have to be duplicated
* in order to make their rr_subject point to the new process.
*/
LIST_FOREACH(link, &parent->p_racct->r_rule_links, rrl_next) {
if (link->rrl_rule->rr_subject_type ==
RCTL_SUBJECT_TYPE_PROCESS) {
rule = rctl_rule_duplicate(link->rrl_rule, M_NOWAIT);
if (rule == NULL)
goto fail;
KASSERT(rule->rr_subject.rs_proc == parent,
("rule->rr_subject.rs_proc != parent"));
rule->rr_subject.rs_proc = child;
error = rctl_racct_add_rule_locked(child->p_racct,
rule);
rctl_rule_release(rule);
if (error != 0)
goto fail;
} else {
error = rctl_racct_add_rule_locked(child->p_racct,
link->rrl_rule);
if (error != 0)
goto fail;
}
}
rw_wunlock(&rctl_lock);
return (0);
fail:
while (!LIST_EMPTY(&child->p_racct->r_rule_links)) {
link = LIST_FIRST(&child->p_racct->r_rule_links);
LIST_REMOVE(link, rrl_next);
rctl_rule_release(link->rrl_rule);
uma_zfree(rctl_rule_link_zone, link);
}
rw_wunlock(&rctl_lock);
return (EAGAIN);
}
/*
* Release rules attached to the racct.
*/
void
rctl_racct_release(struct racct *racct)
{
struct rctl_rule_link *link;
rw_wlock(&rctl_lock);
while (!LIST_EMPTY(&racct->r_rule_links)) {
link = LIST_FIRST(&racct->r_rule_links);
LIST_REMOVE(link, rrl_next);
rctl_rule_release(link->rrl_rule);
uma_zfree(rctl_rule_link_zone, link);
}
rw_wunlock(&rctl_lock);
}
static void
rctl_init(void)
{
rctl_rule_link_zone = uma_zcreate("rctl_rule_link",
sizeof(struct rctl_rule_link), NULL, NULL, NULL, NULL,
UMA_ALIGN_PTR, UMA_ZONE_NOFREE);
rctl_rule_zone = uma_zcreate("rctl_rule", sizeof(struct rctl_rule),
NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE);
}
#else /* !RCTL */
int
sys_rctl_get_racct(struct thread *td, struct rctl_get_racct_args *uap)
{
return (ENOSYS);
}
int
sys_rctl_get_rules(struct thread *td, struct rctl_get_rules_args *uap)
{
return (ENOSYS);
}
int
sys_rctl_get_limits(struct thread *td, struct rctl_get_limits_args *uap)
{
return (ENOSYS);
}
int
sys_rctl_add_rule(struct thread *td, struct rctl_add_rule_args *uap)
{
return (ENOSYS);
}
int
sys_rctl_remove_rule(struct thread *td, struct rctl_remove_rule_args *uap)
{
return (ENOSYS);
}
#endif /* !RCTL */
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