Add rctl. It's used by racct to take user-configurable actions based

on the set of rules it maintains and the current resource usage.  It also
privides userland API to manage that ruleset.

Sponsored by:	The FreeBSD Foundation
Reviewed by:	kib (earlier version)

sys/compat/freebsd32/syscalls.master

@@ -965,3 +965,18 @@
 523	AUE_NULL	NOPROTO	{ int getloginclass(char *namebuf, \
 				    size_t namelen); }
 524	AUE_NULL	NOPROTO	{ int setloginclass(const char *namebuf); }
+525	AUE_NULL	NOPROTO	{ int rctl_get_racct(const void *inbufp, \
+				    size_t inbuflen, void *outbufp, \
+				    size_t outbuflen); }
+526	AUE_NULL	NOPROTO	{ int rctl_get_rules(const void *inbufp, \
+				    size_t inbuflen, void *outbufp, \
+				    size_t outbuflen); }
+527	AUE_NULL	NOPROTO	{ int rctl_get_limits(const void *inbufp, \
+				    size_t inbuflen, void *outbufp, \
+				    size_t outbuflen); }
+528	AUE_NULL	NOPROTO	{ int rctl_add_rule(const void *inbufp, \
+				    size_t inbuflen, void *outbufp, \
+				    size_t outbuflen); }
+529	AUE_NULL	NOPROTO	{ int rctl_remove_rule(const void *inbufp, \
+				    size_t inbuflen, void *outbufp, \
+				    size_t outbuflen); }

sys/conf/NOTES

@@ -2933,6 +2933,9 @@ options 	AAC_DEBUG	# Debugging levels:
 # Resource Accounting
 options 	RACCT
 
+# Resource Limits
+options 	RCTL
+
 # Yet more undocumented options for linting.
 # BKTR_ALLOC_PAGES has no effect except to cause warnings, and
 # BROOKTREE_ALLOC_PAGES hasn't actually been superseded by it, since the

sys/conf/files

@@ -2226,6 +2226,7 @@ kern/kern_priv.c		standard
 kern/kern_proc.c		standard
 kern/kern_prot.c		standard
 kern/kern_racct.c		standard
+kern/kern_rctl.c		standard
 kern/kern_resource.c		standard
 kern/kern_rmlock.c		standard
 kern/kern_rwlock.c		standard

sys/conf/options

@@ -876,6 +876,9 @@ IPOIB_CM	opt_ofed.h
 # Resource Accounting
 RACCT		opt_global.h
 
+# Resource Limits
+RCTL		opt_global.h
+
 # At least one of the AR71XX ubiquiti boards has a Redboot configuration
 # that "lies" about the amount of RAM it has. Until a cleaner method is
 # defined, this option will suffice in overriding what Redboot says.

sys/kern/kern_jail.c

@@ -50,6 +50,7 @@ __FBSDID("$FreeBSD$");
 #include <sys/lock.h>
 #include <sys/mutex.h>
 #include <sys/racct.h>
+#include <sys/rctl.h>
 #include <sys/sx.h>
 #include <sys/sysent.h>
 #include <sys/namei.h>
@@ -2532,6 +2533,9 @@ prison_deref(struct prison *pr, int flags)
 		if (pr->pr_cpuset != NULL)
 			cpuset_rel(pr->pr_cpuset);
 		osd_jail_exit(pr);
+#ifdef RCTL
+		rctl_racct_release(pr->pr_racct);
+#endif
 		racct_destroy(&pr->pr_racct);
 		free(pr, M_PRISON);
 

sys/kern/syscalls.master

@@ -929,5 +929,20 @@
 523	AUE_NULL	STD	{ int getloginclass(char *namebuf, \
 				    size_t namelen); }
 524	AUE_NULL	STD	{ int setloginclass(const char *namebuf); }
+525	AUE_NULL	STD	{ int rctl_get_racct(const void *inbufp, \
+				    size_t inbuflen, void *outbufp, \
+				    size_t outbuflen); }
+526	AUE_NULL	STD	{ int rctl_get_rules(const void *inbufp, \
+				    size_t inbuflen, void *outbufp, \
+				    size_t outbuflen); }
+527	AUE_NULL	STD	{ int rctl_get_limits(const void *inbufp, \
+				    size_t inbuflen, void *outbufp, \
+				    size_t outbuflen); }
+528	AUE_NULL	STD	{ int rctl_add_rule(const void *inbufp, \
+				    size_t inbuflen, void *outbufp, \
+				    size_t outbuflen); }
+529	AUE_NULL	STD	{ int rctl_remove_rule(const void *inbufp, \
+				    size_t inbuflen, void *outbufp, \
+				    size_t outbuflen); }
 ; Please copy any additions and changes to the following compatability tables:
 ; sys/compat/freebsd32/syscalls.master

sys/sys/priv.h

@@ -483,10 +483,19 @@
 #define	PRIV_AFS_ADMIN		660	/* Can change AFS client settings. */
 #define	PRIV_AFS_DAEMON		661	/* Can become the AFS daemon. */
 
+/*
+ * Resource Limits privileges.
+ */
+#define	PRIV_RCTL_GET_RULES	670
+#define	PRIV_RCTL_ADD_RULE	671
+#define	PRIV_RCTL_REMOVE_RULE	672
+#define	PRIV_RCTL_GET_USAGE	673
+#define	PRIV_RCTL_GET_LIMITS	674
+
 /*
  * Track end of privilege list.
  */
-#define	_PRIV_HIGHEST		662
+#define	_PRIV_HIGHEST		675
 
 /*
  * Validate that a named privilege is known by the privilege system.  Invalid

sys/sys/rctl.h

@@ -0,0 +1,169 @@
+/*-
+ * 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.
+ *
+ * $FreeBSD$
+ */
+
+/*
+ * Resource Limits.
+ */
+
+#ifndef _RCTL_H_
+#define	_RCTL_H_
+
+#include <sys/cdefs.h>
+#include <sys/queue.h>
+#include <sys/types.h>
+#include <sys/_task.h>
+
+struct proc;
+struct uidinfo;
+struct loginclass;
+struct prison;
+struct ucred;
+struct rctl_rule_link;
+
+#ifdef _KERNEL
+
+/*
+ * Rules describe an action to be taken when conditions defined
+ * in the rule are met.  There is no global list of rules; instead,
+ * rules are linked to by the racct structures for all the subjects
+ * they apply to - for example, a rule of type "user" is linked to the
+ * appropriate struct uidinfo, and to all the processes of that user.
+ *
+ * 'rr_refcount' is equal to the number of rctl_rule_link structures
+ * pointing to the rule.
+ *
+ * This structure must never change after being added, via rctl_rule_link
+ * structures, to subjects.  In order to change a rule, add a new rule
+ * and remove the previous one.
+ */
+struct rctl_rule {
+	int		rr_subject_type;
+	union {
+		struct proc	*rs_proc;
+		struct uidinfo	*rs_uip;
+		struct loginclass *hr_loginclass;
+		struct prison	*rs_prison;
+	} rr_subject;
+	int		rr_per;
+	int		rr_resource;
+	int		rr_action;
+	int64_t		rr_amount;
+	u_int		rr_refcount;
+	struct task	rr_task;
+};
+
+/*
+ * Allowed values for rr_subject_type and rr_per fields.
+ */
+#define	RCTL_SUBJECT_TYPE_UNDEFINED	-1
+#define	RCTL_SUBJECT_TYPE_PROCESS	0x0000
+#define	RCTL_SUBJECT_TYPE_USER		0x0001
+#define	RCTL_SUBJECT_TYPE_LOGINCLASS	0x0003
+#define	RCTL_SUBJECT_TYPE_JAIL		0x0004
+#define	RCTL_SUBJECT_TYPE_MAX		RCTL_SUBJECT_TYPE_JAIL
+
+/*
+ * Allowed values for rr_action field.
+ */
+#define	RCTL_ACTION_UNDEFINED		-1
+#define	RCTL_ACTION_SIGHUP		SIGHUP
+#define	RCTL_ACTION_SIGINT		SIGINT
+#define	RCTL_ACTION_SIGQUIT		SIGQUIT
+#define	RCTL_ACTION_SIGILL		SIGILL
+#define	RCTL_ACTION_SIGTRAP		SIGTRAP
+#define	RCTL_ACTION_SIGABRT		SIGABRT
+#define	RCTL_ACTION_SIGEMT		SIGEMT
+#define	RCTL_ACTION_SIGFPE		SIGFPE
+#define	RCTL_ACTION_SIGKILL		SIGKILL
+#define	RCTL_ACTION_SIGBUS		SIGBUS
+#define	RCTL_ACTION_SIGSEGV		SIGSEGV
+#define	RCTL_ACTION_SIGSYS		SIGSYS
+#define	RCTL_ACTION_SIGPIPE		SIGPIPE
+#define	RCTL_ACTION_SIGALRM		SIGALRM
+#define	RCTL_ACTION_SIGTERM		SIGTERM
+#define	RCTL_ACTION_SIGURG		SIGURG
+#define	RCTL_ACTION_SIGSTOP		SIGSTOP
+#define	RCTL_ACTION_SIGTSTP		SIGTSTP
+#define	RCTL_ACTION_SIGCHLD		SIGCHLD
+#define	RCTL_ACTION_SIGTTIN		SIGTTIN
+#define	RCTL_ACTION_SIGTTOU		SIGTTOU
+#define	RCTL_ACTION_SIGIO		SIGIO
+#define	RCTL_ACTION_SIGXCPU		SIGXCPU
+#define	RCTL_ACTION_SIGXFSZ		SIGXFSZ
+#define	RCTL_ACTION_SIGVTALRM		SIGVTALRM
+#define	RCTL_ACTION_SIGPROF		SIGPROF
+#define	RCTL_ACTION_SIGWINCH		SIGWINCH
+#define	RCTL_ACTION_SIGINFO		SIGINFO
+#define	RCTL_ACTION_SIGUSR1		SIGUSR1
+#define	RCTL_ACTION_SIGUSR2		SIGUSR2
+#define	RCTL_ACTION_SIGTHR		SIGTHR
+#define	RCTL_ACTION_SIGNAL_MAX		RCTL_ACTION_SIGTHR
+#define	RCTL_ACTION_DENY		(RCTL_ACTION_SIGNAL_MAX + 1)
+#define	RCTL_ACTION_LOG			(RCTL_ACTION_SIGNAL_MAX + 2)
+#define	RCTL_ACTION_DEVCTL		(RCTL_ACTION_SIGNAL_MAX + 3)
+#define	RCTL_ACTION_MAX			RCTL_ACTION_DEVCTL
+
+#define	RCTL_AMOUNT_UNDEFINED		-1
+
+struct rctl_rule *rctl_rule_alloc(int flags);
+struct rctl_rule *rctl_rule_duplicate(const struct rctl_rule *rule, int flags);
+void	rctl_rule_acquire(struct rctl_rule *rule);
+void	rctl_rule_release(struct rctl_rule *rule);
+int	rctl_rule_add(struct rctl_rule *rule);
+int	rctl_rule_remove(struct rctl_rule *filter);
+int	rctl_enforce(struct proc *p, int resource, uint64_t amount);
+uint64_t rctl_get_limit(struct proc *p, int resource);
+uint64_t rctl_get_available(struct proc *p, int resource);
+const char *rctl_resource_name(int resource);
+void	rctl_proc_ucred_changed(struct proc *p, struct ucred *newcred);
+int	rctl_proc_fork(struct proc *parent, struct proc *child);
+void	rctl_racct_release(struct racct *racct);
+#else /* !_KERNEL */
+
+/*
+ * Syscall interface.
+ */
+__BEGIN_DECLS
+int	rctl_get_racct(const char *inbufp, size_t inbuflen, char *outbufp,
+	    size_t outbuflen);
+int	rctl_get_rules(const char *inbufp, size_t inbuflen, char *outbufp,
+	    size_t outbuflen);
+int	rctl_get_limits(const char *inbufp, size_t inbuflen, char *outbufp,
+	    size_t outbuflen);
+int	rctl_add_rule(const char *inbufp, size_t inbuflen, char *outbufp,
+	    size_t outbuflen);
+int	rctl_remove_rule(const char *inbufp, size_t inbuflen, char *outbufp,
+	    size_t outbuflen);
+__END_DECLS
+
+#endif /* !_KERNEL */
+
+#endif /* !_RCTL_H_ */