NetBSD/sys/kern/sysv_ipc.c

318 lines
7.8 KiB
C

/* $NetBSD: sysv_ipc.c,v 1.21 2008/04/28 20:24:05 martin Exp $ */
/*-
* Copyright (c) 1998, 2007 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Charles M. Hannum.
*
* 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: sysv_ipc.c,v 1.21 2008/04/28 20:24:05 martin Exp $");
#include "opt_sysv.h"
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/proc.h>
#include <sys/ipc.h>
#ifdef SYSVMSG
#include <sys/msg.h>
#endif
#ifdef SYSVSEM
#include <sys/sem.h>
#endif
#ifdef SYSVSHM
#include <sys/shm.h>
#endif
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/mount.h>
#include <sys/vnode.h>
#include <sys/stat.h>
#include <sys/sysctl.h>
#include <sys/kauth.h>
/*
* Check for ipc permission
*/
int
ipcperm(kauth_cred_t cred, struct ipc_perm *perm, int mode)
{
mode_t mask;
int ismember = 0;
if (kauth_authorize_generic(cred, KAUTH_GENERIC_ISSUSER, NULL) == 0)
return (0);
if (mode == IPC_M) {
if (kauth_cred_geteuid(cred) == perm->uid ||
kauth_cred_geteuid(cred) == perm->cuid)
return (0);
return (EPERM);
}
mask = 0;
if (kauth_cred_geteuid(cred) == perm->uid ||
kauth_cred_geteuid(cred) == perm->cuid) {
if (mode & IPC_R)
mask |= S_IRUSR;
if (mode & IPC_W)
mask |= S_IWUSR;
return ((perm->mode & mask) == mask ? 0 : EACCES);
}
if (kauth_cred_getegid(cred) == perm->gid ||
(kauth_cred_ismember_gid(cred, perm->gid, &ismember) == 0 && ismember) ||
kauth_cred_getegid(cred) == perm->cgid ||
(kauth_cred_ismember_gid(cred, perm->cgid, &ismember) == 0 && ismember)) {
if (mode & IPC_R)
mask |= S_IRGRP;
if (mode & IPC_W)
mask |= S_IWGRP;
return ((perm->mode & mask) == mask ? 0 : EACCES);
}
if (mode & IPC_R)
mask |= S_IROTH;
if (mode & IPC_W)
mask |= S_IWOTH;
return ((perm->mode & mask) == mask ? 0 : EACCES);
}
/*
* sysctl helper routine for kern.ipc.sysvipc_info subtree.
*/
#define FILL_PERM(src, dst) do { \
(dst)._key = (src)._key; \
(dst).uid = (src).uid; \
(dst).gid = (src).gid; \
(dst).cuid = (src).cuid; \
(dst).cgid = (src).cgid; \
(dst).mode = (src).mode; \
(dst)._seq = (src)._seq; \
} while (/*CONSTCOND*/ 0);
#define FILL_MSG(src, dst) do { \
FILL_PERM((src).msg_perm, (dst).msg_perm); \
(dst).msg_qnum = (src).msg_qnum; \
(dst).msg_qbytes = (src).msg_qbytes; \
(dst)._msg_cbytes = (src)._msg_cbytes; \
(dst).msg_lspid = (src).msg_lspid; \
(dst).msg_lrpid = (src).msg_lrpid; \
(dst).msg_stime = (src).msg_stime; \
(dst).msg_rtime = (src).msg_rtime; \
(dst).msg_ctime = (src).msg_ctime; \
} while (/*CONSTCOND*/ 0)
#define FILL_SEM(src, dst) do { \
FILL_PERM((src).sem_perm, (dst).sem_perm); \
(dst).sem_nsems = (src).sem_nsems; \
(dst).sem_otime = (src).sem_otime; \
(dst).sem_ctime = (src).sem_ctime; \
} while (/*CONSTCOND*/ 0)
#define FILL_SHM(src, dst) do { \
FILL_PERM((src).shm_perm, (dst).shm_perm); \
(dst).shm_segsz = (src).shm_segsz; \
(dst).shm_lpid = (src).shm_lpid; \
(dst).shm_cpid = (src).shm_cpid; \
(dst).shm_atime = (src).shm_atime; \
(dst).shm_dtime = (src).shm_dtime; \
(dst).shm_ctime = (src).shm_ctime; \
(dst).shm_nattch = (src).shm_nattch; \
} while (/*CONSTCOND*/ 0)
static int
sysctl_kern_sysvipc(SYSCTLFN_ARGS)
{
void *where = oldp;
size_t *sizep = oldlenp;
#ifdef SYSVMSG
struct msg_sysctl_info *msgsi = NULL;
#endif
#ifdef SYSVSEM
struct sem_sysctl_info *semsi = NULL;
#endif
#ifdef SYSVSHM
struct shm_sysctl_info *shmsi = NULL;
#endif
size_t infosize, dssize, tsize, buflen;
void *bf = NULL;
char *start;
int32_t nds;
int i, error, ret;
if (namelen != 1)
return EINVAL;
start = where;
buflen = *sizep;
switch (*name) {
case KERN_SYSVIPC_MSG_INFO:
#ifdef SYSVMSG
infosize = sizeof(msgsi->msginfo);
nds = msginfo.msgmni;
dssize = sizeof(msgsi->msgids[0]);
break;
#else
return EINVAL;
#endif
case KERN_SYSVIPC_SEM_INFO:
#ifdef SYSVSEM
infosize = sizeof(semsi->seminfo);
nds = seminfo.semmni;
dssize = sizeof(semsi->semids[0]);
break;
#else
return EINVAL;
#endif
case KERN_SYSVIPC_SHM_INFO:
#ifdef SYSVSHM
infosize = sizeof(shmsi->shminfo);
nds = shminfo.shmmni;
dssize = sizeof(shmsi->shmids[0]);
break;
#else
return EINVAL;
#endif
default:
return EINVAL;
}
/*
* Round infosize to 64 bit boundary if requesting more than just
* the info structure or getting the total data size.
*/
if (where == NULL || *sizep > infosize)
infosize = roundup(infosize, sizeof(quad_t));
tsize = infosize + nds * dssize;
/* Return just the total size required. */
if (where == NULL) {
*sizep = tsize;
return 0;
}
/* Not enough room for even the info struct. */
if (buflen < infosize) {
*sizep = 0;
return ENOMEM;
}
bf = malloc(min(tsize, buflen), M_TEMP, M_WAITOK | M_ZERO);
switch (*name) {
#ifdef SYSVMSG
case KERN_SYSVIPC_MSG_INFO:
msgsi = (struct msg_sysctl_info *)bf;
msgsi->msginfo = msginfo;
break;
#endif
#ifdef SYSVSEM
case KERN_SYSVIPC_SEM_INFO:
semsi = (struct sem_sysctl_info *)bf;
semsi->seminfo = seminfo;
break;
#endif
#ifdef SYSVSHM
case KERN_SYSVIPC_SHM_INFO:
shmsi = (struct shm_sysctl_info *)bf;
shmsi->shminfo = shminfo;
break;
#endif
}
buflen -= infosize;
ret = 0;
if (buflen > 0) {
/* Fill in the IPC data structures. */
for (i = 0; i < nds; i++) {
if (buflen < dssize) {
ret = ENOMEM;
break;
}
switch (*name) {
#ifdef SYSVMSG
case KERN_SYSVIPC_MSG_INFO:
mutex_enter(&msgmutex);
FILL_MSG(msqs[i].msq_u, msgsi->msgids[i]);
mutex_exit(&msgmutex);
break;
#endif
#ifdef SYSVSEM
case KERN_SYSVIPC_SEM_INFO:
FILL_SEM(sema[i], semsi->semids[i]);
break;
#endif
#ifdef SYSVSHM
case KERN_SYSVIPC_SHM_INFO:
FILL_SHM(shmsegs[i], shmsi->shmids[i]);
break;
#endif
}
buflen -= dssize;
}
}
*sizep -= buflen;
error = copyout(bf, start, *sizep);
/* If copyout succeeded, use return code set earlier. */
if (error == 0)
error = ret;
if (bf)
free(bf, M_TEMP);
return error;
}
#undef FILL_PERM
#undef FILL_MSG
#undef FILL_SEM
#undef FILL_SHM
SYSCTL_SETUP(sysctl_ipc_setup, "sysctl kern.ipc subtree setup")
{
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT,
CTLTYPE_NODE, "kern", NULL,
NULL, 0, NULL, 0,
CTL_KERN, CTL_EOL);
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT,
CTLTYPE_NODE, "ipc",
SYSCTL_DESCR("SysV IPC options"),
NULL, 0, NULL, 0,
CTL_KERN, KERN_SYSVIPC, CTL_EOL);
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT,
CTLTYPE_STRUCT, "sysvipc_info",
SYSCTL_DESCR("System V style IPC information"),
sysctl_kern_sysvipc, 0, NULL, 0,
CTL_KERN, KERN_SYSVIPC, KERN_SYSVIPC_INFO, CTL_EOL);
}