int
sys_msgget(struct proc *p, void *v, register_t *retval)
{
struct sys_msgget_args /* {
syscallarg(key_t) key;
syscallarg(int) msgflg;
} */ *uap = v;
int msqid, eval;
int key = SCARG(uap, key);
int msgflg = SCARG(uap, msgflg);
struct ucred *cred = p->p_ucred;
struct msqid_kernel *msqkptr = NULL;
DPRINTF(("msgget(0x%x, 0%o)\n", key, msgflg));
if (key != IPC_PRIVATE) {
for (msqid = 0; msqid < msginfo.msgmni; msqid++) {
msqkptr = &msqids[msqid];
if (msqkptr->u.msg_qbytes != 0 &&
msqkptr->u.msg_perm.key == key)
break;
}
if (msqid < msginfo.msgmni) {
DPRINTF(("found public key\n"));
if ((msgflg & IPC_CREAT) && (msgflg & IPC_EXCL)) {
DPRINTF(("not exclusive\n"));
return (EEXIST);
}
if ((eval = ipcperm(cred, &msqkptr->u.msg_perm,
msgflg & 0700 ))) {
DPRINTF(("requester doesn't have 0%o access\n",
msgflg & 0700));
return (eval);
}
#ifdef MAC
eval = mac_sysvmsq_check_msqget(cred, msqkptr);
if (eval)
return (eval);
#endif
goto found;
}
}
DPRINTF(("need to allocate the msqid_ds\n"));
if (key == IPC_PRIVATE || (msgflg & IPC_CREAT)) {
for (msqid = 0; msqid < msginfo.msgmni; msqid++) {
/*
* Look for an unallocated and unlocked msqid_ds.
* msqid_ds's can be locked by msgsnd or msgrcv while
* they are copying the message in/out. We can't
* re-use the entry until they release it.
*/
msqkptr = &msqids[msqid];
if (msqkptr->u.msg_qbytes == 0 &&
(msqkptr->u.msg_perm.mode & MSG_LOCKED) == 0)
break;
}
if (msqid == msginfo.msgmni) {
DPRINTF(("no more msqid_ds's available\n"));
return (ENOSPC);
}
DPRINTF(("msqid %d is available\n", msqid));
msqkptr->u.msg_perm.key = key;
msqkptr->u.msg_perm.cuid = cred->cr_uid;
msqkptr->u.msg_perm.uid = cred->cr_uid;
msqkptr->u.msg_perm.cgid = cred->cr_gid;
msqkptr->u.msg_perm.gid = cred->cr_gid;
msqkptr->u.msg_perm.mode = (msgflg & 0777);
/* Make sure that the returned msqid is unique */
msqkptr->u.msg_perm.seq =
(msqkptr->u.msg_perm.seq + 1) & 0x7fff;
msqkptr->u.msg_first = NULL;
msqkptr->u.msg_last = NULL;
msqkptr->u.msg_cbytes = 0;
msqkptr->u.msg_qnum = 0;
msqkptr->u.msg_qbytes = msginfo.msgmnb;
msqkptr->u.msg_lspid = 0;
msqkptr->u.msg_lrpid = 0;
msqkptr->u.msg_stime = 0;
msqkptr->u.msg_rtime = 0;
msqkptr->u.msg_ctime = time_second;
#ifdef MAC
mac_sysvmsq_create(cred, msqkptr);
#endif
} else {
DPRINTF(("didn't find it and wasn't asked to create it\n"));
return (ENOENT);
}
found:
/* Construct the unique msqid */
*retval = IXSEQ_TO_IPCID(msqid, msqkptr->u.msg_perm);
return (0);
}
int
msgget(__unused struct proc *p, struct msgget_args *uap, int32_t *retval)
{
int msqid, eval;
int key = uap->key;
int msgflg = uap->msgflg;
kauth_cred_t cred = kauth_cred_get();
struct msqid_kernel *msqptr = NULL;
SYSV_MSG_SUBSYS_LOCK();
if (!msginit(0)) {
eval = ENOMEM;
goto msggetout;
}
#ifdef MSG_DEBUG_OK
printf("msgget(0x%x, 0%o)\n", key, msgflg);
#endif
if (key != IPC_PRIVATE) {
for (msqid = 0; msqid < msginfo.msgmni; msqid++) {
msqptr = &msqids[msqid];
if (msqptr->u.msg_qbytes != 0 &&
msqptr->u.msg_perm._key == key)
break;
}
if (msqid < msginfo.msgmni) {
#ifdef MSG_DEBUG_OK
printf("found public key\n");
#endif
if ((msgflg & IPC_CREAT) && (msgflg & IPC_EXCL)) {
#ifdef MSG_DEBUG_OK
printf("not exclusive\n");
#endif
eval = EEXIST;
goto msggetout;
}
if ((eval = ipcperm(cred, &msqptr->u.msg_perm, msgflg & 0700 ))) {
#ifdef MSG_DEBUG_OK
printf("requester doesn't have 0%o access\n",
msgflg & 0700);
#endif
goto msggetout;
}
#if CONFIG_MACF
eval = mac_sysvmsq_check_msqget(cred, msqptr);
if (eval)
goto msggetout;
#endif
goto found;
}
}
#ifdef MSG_DEBUG_OK
printf("need to allocate the user_msqid_ds\n");
#endif
if (key == IPC_PRIVATE || (msgflg & IPC_CREAT)) {
for (msqid = 0; msqid < msginfo.msgmni; msqid++) {
/*
* Look for an unallocated and unlocked user_msqid_ds.
* user_msqid_ds's can be locked by msgsnd or msgrcv
* while they are copying the message in/out. We
* can't re-use the entry until they release it.
*/
msqptr = &msqids[msqid];
if (msqptr->u.msg_qbytes == 0 &&
(msqptr->u.msg_perm.mode & MSG_LOCKED) == 0)
break;
}
if (msqid == msginfo.msgmni) {
#ifdef MSG_DEBUG_OK
printf("no more user_msqid_ds's available\n");
#endif
eval = ENOSPC;
goto msggetout;
}
#ifdef MSG_DEBUG_OK
printf("msqid %d is available\n", msqid);
#endif
msqptr->u.msg_perm._key = key;
msqptr->u.msg_perm.cuid = kauth_cred_getuid(cred);
msqptr->u.msg_perm.uid = kauth_cred_getuid(cred);
msqptr->u.msg_perm.cgid = kauth_cred_getgid(cred);
msqptr->u.msg_perm.gid = kauth_cred_getgid(cred);
msqptr->u.msg_perm.mode = (msgflg & 0777);
/* Make sure that the returned msqid is unique */
msqptr->u.msg_perm._seq++;
msqptr->u.msg_first = NULL;
msqptr->u.msg_last = NULL;
msqptr->u.msg_cbytes = 0;
msqptr->u.msg_qnum = 0;
msqptr->u.msg_qbytes = msginfo.msgmnb;
msqptr->u.msg_lspid = 0;
msqptr->u.msg_lrpid = 0;
msqptr->u.msg_stime = 0;
msqptr->u.msg_rtime = 0;
msqptr->u.msg_ctime = sysv_msgtime();
#if CONFIG_MACF
mac_sysvmsq_label_associate(cred, msqptr);
#endif
} else {
#ifdef MSG_DEBUG_OK
printf("didn't find it and wasn't asked to create it\n");
#endif
eval = ENOENT;
goto msggetout;
}
found:
/* Construct the unique msqid */
*retval = IXSEQ_TO_IPCID(msqid, msqptr->u.msg_perm);
AUDIT_ARG(svipc_id, *retval);
eval = 0;
msggetout:
SYSV_MSG_SUBSYS_UNLOCK();
return(eval);
}
