usr.bin/ipcs/ipc.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-3-Clause
   3  *
   4  * Copyright (c) 1994 SigmaSoft, Th. Lockert <tholo@sigmasoft.com>
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. The name of the author may not be used to endorse or promote products
  16  *    derived from this software without specific prior written permission.
  17  *
  18  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
  19  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
  20  * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
  21  * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  22  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  23  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
  24  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
  25  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  26  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  27  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  28  *
  29  * The split of ipcs.c into ipcs.c and ipc.c to accommodate the
  30  * changes in ipcrm.c was done by Edwin Groothuis <edwin@FreeBSD.org>
  31  */
  32
  33 #include <sys/cdefs.h>
  34 __FBSDID("$FreeBSD$");
  35
  36 #include <sys/types.h>
  37 #include <sys/sysctl.h>
  38 #define _WANT_SYSVMSG_INTERNALS
  39 #include <sys/msg.h>
  40 #define _WANT_SYSVSEM_INTERNALS
  41 #include <sys/sem.h>
  42 #define _WANT_SYSVSHM_INTERNALS
  43 #include <sys/shm.h>
  44
  45 #include <assert.h>
  46 #include <err.h>
  47 #include <kvm.h>
  48 #include <nlist.h>
  49 #include <stddef.h>
  50
  51 #include "ipc.h"
  52
  53 int     use_sysctl = 1;
  54 struct semid_kernel     *sema;
  55 struct seminfo          seminfo;
  56 struct msginfo          msginfo;
  57 struct msqid_kernel     *msqids;
  58 struct shminfo          shminfo;
  59 struct shmid_kernel     *shmsegs;
  60
  61 struct nlist symbols[] = {
  62         { .n_name = "sema" },
  63         { .n_name = "seminfo" },
  64         { .n_name = "msginfo" },
  65         { .n_name = "msqids" },
  66         { .n_name = "shminfo" },
  67         { .n_name = "shmsegs" },
  68         { .n_name = NULL }
  69 };
  70
  71 #define SHMINFO_XVEC    X(shmmax, sizeof(u_long))                       \
  72                         X(shmmin, sizeof(u_long))                       \
  73                         X(shmmni, sizeof(u_long))                       \
  74                         X(shmseg, sizeof(u_long))                       \
  75                         X(shmall, sizeof(u_long))
  76
  77 #define SEMINFO_XVEC    X(semmni, sizeof(int))                          \
  78                         X(semmns, sizeof(int))                          \
  79                         X(semmnu, sizeof(int))                          \
  80                         X(semmsl, sizeof(int))                          \
  81                         X(semopm, sizeof(int))                          \
  82                         X(semume, sizeof(int))                          \
  83                         X(semusz, sizeof(int))                          \
  84                         X(semvmx, sizeof(int))                          \
  85                         X(semaem, sizeof(int))
  86
  87 #define MSGINFO_XVEC    X(msgmax, sizeof(int))                          \
  88                         X(msgmni, sizeof(int))                          \
  89                         X(msgmnb, sizeof(int))                          \
  90                         X(msgtql, sizeof(int))                          \
  91                         X(msgssz, sizeof(int))                          \
  92                         X(msgseg, sizeof(int))
  93
  94 #define X(a, b) { "kern.ipc." #a, offsetof(TYPEC, a), (b) },
  95 #define TYPEC   struct shminfo
  96 static struct scgs_vector shminfo_scgsv[] = { SHMINFO_XVEC { .sysctl=NULL } };
  97 #undef  TYPEC
  98 #define TYPEC   struct seminfo
  99 static struct scgs_vector seminfo_scgsv[] = { SEMINFO_XVEC { .sysctl=NULL } };
 100 #undef  TYPEC
 101 #define TYPEC   struct msginfo
 102 static struct scgs_vector msginfo_scgsv[] = { MSGINFO_XVEC { .sysctl=NULL } };
 103 #undef  TYPEC
 104 #undef  X
 105
 106 kvm_t *kd;
 107
 108 void
 109 sysctlgatherstruct(void *addr, size_t size, struct scgs_vector *vecarr)
 110 {
 111         struct scgs_vector *xp;
 112         size_t tsiz;
 113         int rv;
 114
 115         for (xp = vecarr; xp->sysctl != NULL; xp++) {
 116                 assert(xp->offset <= size);
 117                 tsiz = xp->size;
 118                 rv = sysctlbyname(xp->sysctl, (char *)addr + xp->offset,
 119                     &tsiz, NULL, 0);
 120                 if (rv == -1)
 121                         err(1, "sysctlbyname: %s", xp->sysctl);
 122                 if (tsiz != xp->size)
 123                         errx(1, "%s size mismatch (expected %zu, got %zu)",
 124                             xp->sysctl, xp->size, tsiz);
 125         }
 126 }
 127
 128 void
 129 kget(int idx, void *addr, size_t size)
 130 {
 131         const char *symn;               /* symbol name */
 132         size_t tsiz;
 133         int rv;
 134         unsigned long kaddr;
 135         const char *sym2sysctl[] = {    /* symbol to sysctl name table */
 136                 "kern.ipc.sema",
 137                 "kern.ipc.seminfo",
 138                 "kern.ipc.msginfo",
 139                 "kern.ipc.msqids",
 140                 "kern.ipc.shminfo",
 141                 "kern.ipc.shmsegs" };
 142
 143         assert((unsigned)idx <= sizeof(sym2sysctl) / sizeof(*sym2sysctl));
 144         if (!use_sysctl) {
 145                 symn = symbols[idx].n_name;
 146                 if (*symn == '_')
 147                         symn++;
 148                 if (symbols[idx].n_type == 0 || symbols[idx].n_value == 0)
 149                         errx(1, "symbol %s undefined", symn);
 150                 /*
 151                  * For some symbols, the value we retrieve is
 152                  * actually a pointer; since we want the actual value,
 153                  * we have to manually dereference it.
 154                  */
 155                 switch (idx) {
 156                 case X_MSQIDS:
 157                         tsiz = sizeof(msqids);
 158                         rv = kvm_read(kd, symbols[idx].n_value,
 159                             &msqids, tsiz);
 160                         kaddr = (u_long)msqids;
 161                         break;
 162                 case X_SHMSEGS:
 163                         tsiz = sizeof(shmsegs);
 164                         rv = kvm_read(kd, symbols[idx].n_value,
 165                             &shmsegs, tsiz);
 166                         kaddr = (u_long)shmsegs;
 167                         break;
 168                 case X_SEMA:
 169                         tsiz = sizeof(sema);
 170                         rv = kvm_read(kd, symbols[idx].n_value,
 171                             &sema, tsiz);
 172                         kaddr = (u_long)sema;
 173                         break;
 174                 default:
 175                         rv = tsiz = 0;
 176                         kaddr = symbols[idx].n_value;
 177                         break;
 178                 }
 179                 if ((unsigned)rv != tsiz)
 180                         errx(1, "%s: %s", symn, kvm_geterr(kd));
 181                 if ((unsigned)kvm_read(kd, kaddr, addr, size) != size)
 182                         errx(1, "%s: %s", symn, kvm_geterr(kd));
 183         } else {
 184                 switch (idx) {
 185                 case X_SHMINFO:
 186                         sysctlgatherstruct(addr, size, shminfo_scgsv);
 187                         break;
 188                 case X_SEMINFO:
 189                         sysctlgatherstruct(addr, size, seminfo_scgsv);
 190                         break;
 191                 case X_MSGINFO:
 192                         sysctlgatherstruct(addr, size, msginfo_scgsv);
 193                         break;
 194                 default:
 195                         tsiz = size;
 196                         rv = sysctlbyname(sym2sysctl[idx], addr, &tsiz,
 197                             NULL, 0);
 198                         if (rv == -1)
 199                                 err(1, "sysctlbyname: %s", sym2sysctl[idx]);
 200                         if (tsiz != size)
 201                                 errx(1, "%s size mismatch "
 202                                     "(expected %zu, got %zu)",
 203                                     sym2sysctl[idx], size, tsiz);
 204                         break;
 205                 }
 206         }
 207 }