sysv_ipc.c revision 1.20
1 /* $NetBSD: sysv_ipc.c,v 1.20 2007/02/09 21:55:31 ad Exp $ */ 2 3 /*- 4 * Copyright (c) 1998, 2007 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Charles M. Hannum. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the NetBSD 21 * Foundation, Inc. and its contributors. 22 * 4. Neither the name of The NetBSD Foundation nor the names of its 23 * contributors may be used to endorse or promote products derived 24 * from this software without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 29 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 36 * POSSIBILITY OF SUCH DAMAGE. 37 */ 38 39 #include <sys/cdefs.h> 40 __KERNEL_RCSID(0, "$NetBSD: sysv_ipc.c,v 1.20 2007/02/09 21:55:31 ad Exp $"); 41 42 #include "opt_sysv.h" 43 44 #include <sys/param.h> 45 #include <sys/kernel.h> 46 #include <sys/proc.h> 47 #include <sys/ipc.h> 48 #ifdef SYSVMSG 49 #include <sys/msg.h> 50 #endif 51 #ifdef SYSVSEM 52 #include <sys/sem.h> 53 #endif 54 #ifdef SYSVSHM 55 #include <sys/shm.h> 56 #endif 57 #include <sys/systm.h> 58 #include <sys/malloc.h> 59 #include <sys/mount.h> 60 #include <sys/vnode.h> 61 #include <sys/stat.h> 62 #include <sys/sysctl.h> 63 #include <sys/kauth.h> 64 65 /* 66 * Check for ipc permission 67 */ 68 69 int 70 ipcperm(kauth_cred_t cred, struct ipc_perm *perm, int mode) 71 { 72 mode_t mask; 73 int ismember = 0; 74 75 if (kauth_authorize_generic(cred, KAUTH_GENERIC_ISSUSER, NULL) == 0) 76 return (0); 77 78 if (mode == IPC_M) { 79 if (kauth_cred_geteuid(cred) == perm->uid || 80 kauth_cred_geteuid(cred) == perm->cuid) 81 return (0); 82 return (EPERM); 83 } 84 85 mask = 0; 86 87 if (kauth_cred_geteuid(cred) == perm->uid || 88 kauth_cred_geteuid(cred) == perm->cuid) { 89 if (mode & IPC_R) 90 mask |= S_IRUSR; 91 if (mode & IPC_W) 92 mask |= S_IWUSR; 93 return ((perm->mode & mask) == mask ? 0 : EACCES); 94 } 95 96 if (kauth_cred_getegid(cred) == perm->gid || 97 (kauth_cred_ismember_gid(cred, perm->gid, &ismember) == 0 && ismember) || 98 kauth_cred_getegid(cred) == perm->cgid || 99 (kauth_cred_ismember_gid(cred, perm->cgid, &ismember) == 0 && ismember)) { 100 if (mode & IPC_R) 101 mask |= S_IRGRP; 102 if (mode & IPC_W) 103 mask |= S_IWGRP; 104 return ((perm->mode & mask) == mask ? 0 : EACCES); 105 } 106 107 if (mode & IPC_R) 108 mask |= S_IROTH; 109 if (mode & IPC_W) 110 mask |= S_IWOTH; 111 return ((perm->mode & mask) == mask ? 0 : EACCES); 112 } 113 114 /* 115 * sysctl helper routine for kern.ipc.sysvipc_info subtree. 116 */ 117 118 #define FILL_PERM(src, dst) do { \ 119 (dst)._key = (src)._key; \ 120 (dst).uid = (src).uid; \ 121 (dst).gid = (src).gid; \ 122 (dst).cuid = (src).cuid; \ 123 (dst).cgid = (src).cgid; \ 124 (dst).mode = (src).mode; \ 125 (dst)._seq = (src)._seq; \ 126 } while (/*CONSTCOND*/ 0); 127 128 #define FILL_MSG(src, dst) do { \ 129 FILL_PERM((src).msg_perm, (dst).msg_perm); \ 130 (dst).msg_qnum = (src).msg_qnum; \ 131 (dst).msg_qbytes = (src).msg_qbytes; \ 132 (dst)._msg_cbytes = (src)._msg_cbytes; \ 133 (dst).msg_lspid = (src).msg_lspid; \ 134 (dst).msg_lrpid = (src).msg_lrpid; \ 135 (dst).msg_stime = (src).msg_stime; \ 136 (dst).msg_rtime = (src).msg_rtime; \ 137 (dst).msg_ctime = (src).msg_ctime; \ 138 } while (/*CONSTCOND*/ 0) 139 140 #define FILL_SEM(src, dst) do { \ 141 FILL_PERM((src).sem_perm, (dst).sem_perm); \ 142 (dst).sem_nsems = (src).sem_nsems; \ 143 (dst).sem_otime = (src).sem_otime; \ 144 (dst).sem_ctime = (src).sem_ctime; \ 145 } while (/*CONSTCOND*/ 0) 146 147 #define FILL_SHM(src, dst) do { \ 148 FILL_PERM((src).shm_perm, (dst).shm_perm); \ 149 (dst).shm_segsz = (src).shm_segsz; \ 150 (dst).shm_lpid = (src).shm_lpid; \ 151 (dst).shm_cpid = (src).shm_cpid; \ 152 (dst).shm_atime = (src).shm_atime; \ 153 (dst).shm_dtime = (src).shm_dtime; \ 154 (dst).shm_ctime = (src).shm_ctime; \ 155 (dst).shm_nattch = (src).shm_nattch; \ 156 } while (/*CONSTCOND*/ 0) 157 158 static int 159 sysctl_kern_sysvipc(SYSCTLFN_ARGS) 160 { 161 void *where = oldp; 162 size_t *sizep = oldlenp; 163 #ifdef SYSVMSG 164 struct msg_sysctl_info *msgsi = NULL; 165 #endif 166 #ifdef SYSVSEM 167 struct sem_sysctl_info *semsi = NULL; 168 #endif 169 #ifdef SYSVSHM 170 struct shm_sysctl_info *shmsi = NULL; 171 #endif 172 size_t infosize, dssize, tsize, buflen; 173 void *bf = NULL; 174 char *start; 175 int32_t nds; 176 int i, error, ret; 177 178 if (namelen != 1) 179 return EINVAL; 180 181 start = where; 182 buflen = *sizep; 183 184 switch (*name) { 185 case KERN_SYSVIPC_MSG_INFO: 186 #ifdef SYSVMSG 187 infosize = sizeof(msgsi->msginfo); 188 nds = msginfo.msgmni; 189 dssize = sizeof(msgsi->msgids[0]); 190 break; 191 #else 192 return EINVAL; 193 #endif 194 case KERN_SYSVIPC_SEM_INFO: 195 #ifdef SYSVSEM 196 infosize = sizeof(semsi->seminfo); 197 nds = seminfo.semmni; 198 dssize = sizeof(semsi->semids[0]); 199 break; 200 #else 201 return EINVAL; 202 #endif 203 case KERN_SYSVIPC_SHM_INFO: 204 #ifdef SYSVSHM 205 infosize = sizeof(shmsi->shminfo); 206 nds = shminfo.shmmni; 207 dssize = sizeof(shmsi->shmids[0]); 208 break; 209 #else 210 return EINVAL; 211 #endif 212 default: 213 return EINVAL; 214 } 215 /* 216 * Round infosize to 64 bit boundary if requesting more than just 217 * the info structure or getting the total data size. 218 */ 219 if (where == NULL || *sizep > infosize) 220 infosize = roundup(infosize, sizeof(quad_t)); 221 tsize = infosize + nds * dssize; 222 223 /* Return just the total size required. */ 224 if (where == NULL) { 225 *sizep = tsize; 226 return 0; 227 } 228 229 /* Not enough room for even the info struct. */ 230 if (buflen < infosize) { 231 *sizep = 0; 232 return ENOMEM; 233 } 234 bf = malloc(min(tsize, buflen), M_TEMP, M_WAITOK | M_ZERO); 235 236 switch (*name) { 237 #ifdef SYSVMSG 238 case KERN_SYSVIPC_MSG_INFO: 239 msgsi = (struct msg_sysctl_info *)bf; 240 msgsi->msginfo = msginfo; 241 break; 242 #endif 243 #ifdef SYSVSEM 244 case KERN_SYSVIPC_SEM_INFO: 245 semsi = (struct sem_sysctl_info *)bf; 246 semsi->seminfo = seminfo; 247 break; 248 #endif 249 #ifdef SYSVSHM 250 case KERN_SYSVIPC_SHM_INFO: 251 shmsi = (struct shm_sysctl_info *)bf; 252 shmsi->shminfo = shminfo; 253 break; 254 #endif 255 } 256 buflen -= infosize; 257 258 ret = 0; 259 if (buflen > 0) { 260 /* Fill in the IPC data structures. */ 261 for (i = 0; i < nds; i++) { 262 if (buflen < dssize) { 263 ret = ENOMEM; 264 break; 265 } 266 switch (*name) { 267 #ifdef SYSVMSG 268 case KERN_SYSVIPC_MSG_INFO: 269 mutex_enter(&msgmutex); 270 FILL_MSG(msqs[i].msq_u, msgsi->msgids[i]); 271 mutex_exit(&msgmutex); 272 break; 273 #endif 274 #ifdef SYSVSEM 275 case KERN_SYSVIPC_SEM_INFO: 276 FILL_SEM(sema[i], semsi->semids[i]); 277 break; 278 #endif 279 #ifdef SYSVSHM 280 case KERN_SYSVIPC_SHM_INFO: 281 FILL_SHM(shmsegs[i], shmsi->shmids[i]); 282 break; 283 #endif 284 } 285 buflen -= dssize; 286 } 287 } 288 *sizep -= buflen; 289 error = copyout(bf, start, *sizep); 290 /* If copyout succeeded, use return code set earlier. */ 291 if (error == 0) 292 error = ret; 293 if (bf) 294 free(bf, M_TEMP); 295 return error; 296 } 297 298 #undef FILL_PERM 299 #undef FILL_MSG 300 #undef FILL_SEM 301 #undef FILL_SHM 302 303 SYSCTL_SETUP(sysctl_ipc_setup, "sysctl kern.ipc subtree setup") 304 { 305 sysctl_createv(clog, 0, NULL, NULL, 306 CTLFLAG_PERMANENT, 307 CTLTYPE_NODE, "kern", NULL, 308 NULL, 0, NULL, 0, 309 CTL_KERN, CTL_EOL); 310 311 sysctl_createv(clog, 0, NULL, NULL, 312 CTLFLAG_PERMANENT, 313 CTLTYPE_NODE, "ipc", 314 SYSCTL_DESCR("SysV IPC options"), 315 NULL, 0, NULL, 0, 316 CTL_KERN, KERN_SYSVIPC, CTL_EOL); 317 318 sysctl_createv(clog, 0, NULL, NULL, 319 CTLFLAG_PERMANENT, 320 CTLTYPE_STRUCT, "sysvipc_info", 321 SYSCTL_DESCR("System V style IPC information"), 322 sysctl_kern_sysvipc, 0, NULL, 0, 323 CTL_KERN, KERN_SYSVIPC, KERN_SYSVIPC_INFO, CTL_EOL); 324 } 325
Indexes created Wed Sep 24 22:09:59 GMT 2025