/*
 * Copyright (c) 1994 Adam Glass
 * 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.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by Adam Glass.
 * 4. The name of the Author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY Adam Glass ``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 Adam Glass 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: src/usr.bin/ipcrm/ipcrm.c,v 1.11 2002/09/04 23:29:02 dwmalone Exp $");

#include <sys/types.h>
#include <sys/sysctl.h>
#include <sys/cdefs.h>
#define _KERNEL
#include <sys/ipc.h>
#include <sys/msg.h>
#include <sys/sem.h>
#include <sys/shm.h>
#undef _KERNEL
#include <ctype.h>
#include <err.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <assert.h>
#include <limits.h>
#include <fcntl.h>
#include <nlist.h>
#include <kvm.h>

#define IPC_TO_STR(x) (x == 'Q' ? "msq" : (x == 'M' ? "shm" : "sem"))
#define IPC_TO_STRING(x) (x == 'Q' ? "message queue" : \
			  (x == 'M' ? "shared memory segment" : "semaphore"))

/* Copied from ipcs/ipcs.c */
/* SysCtlGatherStruct structure. */
struct scgs_vector {
	const char *sysctl;
	off_t offset;
	size_t size;
};

static struct semid_kernel	*sema;
static struct seminfo	seminfo;
static struct msginfo	msginfo;
static struct msqid_kernel	*msqids;
static struct shminfo	shminfo;
static struct shmid_kernel	*shmsegs;

void	kget(int idx, void *addr, size_t size);
void	sysctlgatherstruct(void *addr, size_t size, struct scgs_vector *vec);

static struct nlist symbols[] = {
	{"sema"},
#define X_SEMA		0
	{"seminfo"},
#define X_SEMINFO	1
	{"msginfo"},
#define X_MSGINFO	2
	{"msqids"},
#define X_MSQIDS	3
	{"shminfo"},
#define X_SHMINFO	4
	{"shmsegs"},
#define X_SHMSEGS	5
	{NULL}
};

#define	SHMINFO_XVEC				\
	X(shmmax, sizeof(int))			\
	X(shmmin, sizeof(int))			\
	X(shmmni, sizeof(int))			\
	X(shmseg, sizeof(int))			\
	X(shmall, sizeof(int))

#define	SEMINFO_XVEC				\
	X(semmap, sizeof(int))			\
	X(semmni, sizeof(int))			\
	X(semmns, sizeof(int))			\
	X(semmnu, sizeof(int))			\
	X(semmsl, sizeof(int))			\
	X(semopm, sizeof(int))			\
	X(semume, sizeof(int))			\
	X(semusz, sizeof(int))			\
	X(semvmx, sizeof(int))			\
	X(semaem, sizeof(int))

#define	MSGINFO_XVEC				\
	X(msgmax, sizeof(int))			\
	X(msgmni, sizeof(int))			\
	X(msgmnb, sizeof(int))			\
	X(msgtql, sizeof(int))			\
	X(msgssz, sizeof(int))			\
	X(msgseg, sizeof(int))

#define	X(a, b)	{ "kern.ipc." #a, __offsetof(TYPEC, a), (b) },
#define	TYPEC	struct shminfo
struct scgs_vector shminfo_scgsv[] = { SHMINFO_XVEC { NULL } };
#undef	TYPEC
#define	TYPEC	struct seminfo
struct scgs_vector seminfo_scgsv[] = { SEMINFO_XVEC { NULL } };
#undef	TYPEC
#define	TYPEC	struct msginfo
struct scgs_vector msginfo_scgsv[] = { MSGINFO_XVEC { NULL } };
#undef	TYPEC
#undef	X

static int errflg;
static int signaled;
static int use_sysctl = 1;

void usage(void);
int msgrm(key_t, int);
int shmrm(key_t, int);
int semrm(key_t, int);
void not_configured(int);

void
usage(void)
{
	fprintf(stderr, "%s\n%s\n",
		"usage: ipcrm [-q msqid] [-m shmid] [-s semid]",
		"             [-Q msgkey] [-M shmkey] [-S semkey] ...");
	exit(1);
}

int
msgrm(key_t key, int id)
{
	if (key) {
		id = msgget(key, 0);
		if (id == -1)
			return -1;
	}
	if (id == -1) {
		struct msqid_kernel *kxmsqids;
		size_t kxmsqids_len;
		int num;

		kget(X_MSGINFO, &msginfo, sizeof(msginfo));
		kxmsqids_len = sizeof(struct msqid_kernel) * msginfo.msgmni;
		kxmsqids = malloc(kxmsqids_len);
		kget(X_MSQIDS, kxmsqids, kxmsqids_len);
		num = msginfo.msgmni;
		while (num-- && !signaled)
			if (kxmsqids[num].u.msg_qbytes != 0) {
				id = IXSEQ_TO_IPCID(num, kxmsqids[num].u.msg_perm);
				if (msgctl(id, IPC_RMID, NULL) < 0) {
					warn("msqid(%d): ", id);
					errflg++;
				}
			}
		return signaled ? -1 : 0;	/* errors maybe handled above */
	}
	return msgctl(id, IPC_RMID, NULL);
}

int
shmrm(key_t key, int id)
{
	if (key) {
		id = shmget(key, 0, 0);
		if (id == -1)
			return -1;
	}
	if (id == -1) {
		struct shmid_kernel *kxshmids;
		size_t kxshmids_len;
		int num;

		kget(X_SHMINFO, &shminfo, sizeof(shminfo));
		kxshmids_len = sizeof(struct shmid_kernel) * shminfo.shmmni;
		kxshmids = malloc(kxshmids_len);
		kget(X_SHMSEGS, kxshmids, kxshmids_len);
		num = shminfo.shmmni;
		while (num-- && !signaled)
			if (kxshmids[num].u.shm_perm.mode & 0x0800) {
				id = IXSEQ_TO_IPCID(num, kxshmids[num].u.shm_perm);
				if (shmctl(id, IPC_RMID, NULL) < 0) {
					warn("shmid(%d): ", id);
					errflg++;
				}
			}
		return signaled ? -1 : 0;	/* errors maybe handled above */
	}
	return shmctl(id, IPC_RMID, NULL);
}

int
semrm(key_t key, int id)
{
	union semun arg;

	if (key) {
		id = semget(key, 0, 0);
		if (id == -1)
			return -1;
	}
	if (id == -1) {
		struct semid_kernel *kxsema;
		size_t kxsema_len;
		int num;

		kget(X_SEMINFO, &seminfo, sizeof(seminfo));
		kxsema_len = sizeof(struct semid_kernel) * seminfo.semmni;
		kxsema = malloc(kxsema_len);
		kget(X_SEMA, kxsema, kxsema_len);
		num = seminfo.semmni;
		while (num-- && !signaled)
			if ((kxsema[num].u.sem_perm.mode & SEM_ALLOC) != 0) {
				id = IXSEQ_TO_IPCID(num, kxsema[num].u.sem_perm);
				if (semctl(id, IPC_RMID, NULL) < 0) {
					warn("semid(%d): ", id);
					errflg++;
				}
			}
		return signaled ? -1 : 0;	/* errors maybe handled above */
	}
	return semctl(id, 0, IPC_RMID, arg);
}

void
not_configured(int signo __unused)
{
	signaled++;
}

int
main(int argc, char *argv[])
{
	int c, result, target_id;
	key_t target_key;

	errflg = 0;
	signal(SIGSYS, not_configured);
	while ((c = getopt(argc, argv, ":q:m:s:Q:M:S:y")) != -1) {

		signaled = 0;
		switch (c) {
		case 'q':
		case 'm':
		case 's':
			target_id = atoi(optarg);
			if (c == 'q')
				result = msgrm(0, target_id);
			else if (c == 'm')
				result = shmrm(0, target_id);
			else
				result = semrm(0, target_id);
			if (result < 0) {
				errflg++;
				if (!signaled)
					warn("%sid(%d): ", IPC_TO_STR(toupper(c)), target_id);
				else
					warnx("%ss are not configured in the running kernel",
					      IPC_TO_STRING(toupper(c)));
			}
			break;
		case 'Q':
		case 'M':
		case 'S':
			target_key = atol(optarg);
			if (target_key == IPC_PRIVATE) {
				warnx("can't remove private %ss", IPC_TO_STRING(c));
				continue;
			}
			if (c == 'Q')
				result = msgrm(target_key, 0);
			else if (c == 'M')
				result = shmrm(target_key, 0);
			else
				result = semrm(target_key, 0);
			if (result < 0) {
				errflg++;
				if (!signaled)
					warn("%ss(%ld): ", IPC_TO_STR(c), target_key);
				else
					warnx("%ss are not configured in the running kernel",
					      IPC_TO_STRING(c));
			}
			break;
		case 'y':
			use_sysctl = 0;
			break;
		case ':':
			fprintf(stderr, "option -%c requires an argument\n", optopt);
			usage();
		case '?':
			fprintf(stderr, "unrecognized option: -%c\n", optopt);
			usage();
		}
	}

	if (optind != argc) {
		fprintf(stderr, "unknown argument: %s\n", argv[optind]);
		usage();
	}
	exit(errflg);
}

/* The remainder is from ipcs/ipcs.c */
void
sysctlgatherstruct(void *addr, size_t size, struct scgs_vector *vecarr)
{
	struct scgs_vector *xp;
	size_t tsiz;
	int rv;

	for (xp = vecarr; xp->sysctl != NULL; xp++) {
		assert(xp->offset <= size);
		tsiz = xp->size;
		rv = sysctlbyname(xp->sysctl, (char *)addr + xp->offset,
				  &tsiz, NULL, 0);
		if (rv == -1)
			err(1, "sysctlbyname: %s", xp->sysctl);
		if (tsiz != xp->size)
			errx(1, "%s size mismatch (expected %d, got %d)",
			     xp->sysctl, xp->size, tsiz);
	}
}

void
kget(int idx, void *addr, size_t size)
{
	char *symn;			/* symbol name */
	size_t tsiz;
	int rv;
	unsigned long kaddr;
	const char *sym2sysctl[] = {	/* symbol to sysctl name table */
		"kern.ipc.sema",
		"kern.ipc.seminfo",
		"kern.ipc.msginfo",
		"kern.ipc.msqids",
		"kern.ipc.shminfo",
		"kern.ipc.shmsegs" };

	assert((unsigned)idx <= sizeof(sym2sysctl) / sizeof(*sym2sysctl));
	if (!use_sysctl) {
		kvm_t *kd;
		char	kvmoferr[_POSIX2_LINE_MAX];  /* Error buf for kvm_openfiles. */
		char   *core = NULL, *namelist = NULL;

		kd = kvm_openfiles(namelist, core, NULL, O_RDONLY, kvmoferr);
		if (kd == NULL)
			errx(1, "kvm_openfiles: %s", kvmoferr);
		switch (kvm_nlist(kd, symbols)) {
		case 0:
			break;
		case -1:
			errx(1, "unable to read kernel symbol table");
		default:
#ifdef notdef		/* they'll be told more civilly later */
			warnx("nlist failed");
			for (i = 0; symbols[i].n_name != NULL; i++)
				if (symbols[i].n_value == 0)
					warnx("symbol %s not found",
					      symbols[i].n_name);
#endif
			break;
		}
		symn = symbols[idx].n_name;
		if (*symn == '_')
			symn++;
		if (symbols[idx].n_type == 0 || symbols[idx].n_value == 0)
			errx(1, "symbol %s undefined", symn);
		/*
		 * For some symbols, the value we retrieve is
		 * actually a pointer; since we want the actual value,
		 * we have to manually dereference it.
		 */
		switch (idx) {
		case X_MSQIDS:
			tsiz = sizeof(msqids);
			rv = kvm_read(kd, symbols[idx].n_value,
				      &msqids, tsiz);
			kaddr = (u_long)msqids;
			break;
		case X_SHMSEGS:
			tsiz = sizeof(shmsegs);
			rv = kvm_read(kd, symbols[idx].n_value,
				      &shmsegs, tsiz);
			kaddr = (u_long)shmsegs;
			break;
		case X_SEMA:
			tsiz = sizeof(sema);
			rv = kvm_read(kd, symbols[idx].n_value,
				      &sema, tsiz);
			kaddr = (u_long)sema;
			break;
		default:
			rv = tsiz = 0;
			kaddr = symbols[idx].n_value;
			break;
		}
		if ((unsigned)rv != tsiz)
			errx(1, "%s: %s", symn, kvm_geterr(kd));
		if ((unsigned)kvm_read(kd, kaddr, addr, size) != size)
			errx(1, "%s: %s", symn, kvm_geterr(kd));
		kvm_close(kd);
	} else {
		switch (idx) {
		case X_SHMINFO:
			sysctlgatherstruct(addr, size, shminfo_scgsv);
			break;
		case X_SEMINFO:
			sysctlgatherstruct(addr, size, seminfo_scgsv);
			break;
		case X_MSGINFO:
			sysctlgatherstruct(addr, size, msginfo_scgsv);
			break;
		default:
			tsiz = size;
			rv = sysctlbyname(sym2sysctl[idx], addr, &tsiz,
					  NULL, 0);
			if (rv == -1)
				err(1, "sysctlbyname: %s", sym2sysctl[idx]);
			if (tsiz != size)
				errx(1, "%s size mismatch "
				     "(expected %d, got %d)",
				     sym2sysctl[idx], size, tsiz);
			break;
		}
	}
}