#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/proc_internal.h>
#include <sys/kauth.h>
#include <sys/msg.h>
#include <sys/malloc.h>
#include <mach/mach_types.h>
#include <bsm/audit_kernel.h>
#include <sys/filedesc.h>
#include <sys/file_internal.h>
#include <sys/sysctl.h>
#include <sys/sysproto.h>
#include <sys/ipcs.h>
static void msginit(void *);
#define MSG_DEBUG
#undef MSG_DEBUG_OK
static void msg_freehdr(struct msg *msghdr);
typedef int sy_call_t(struct proc *, void *, int *);
static sy_call_t *msgcalls[] = {
(sy_call_t *)msgctl, (sy_call_t *)msgget,
(sy_call_t *)msgsnd, (sy_call_t *)msgrcv
};
static int nfree_msgmaps;
static short free_msgmaps;
static struct msg *free_msghdrs;
char *msgpool;
struct msgmap *msgmaps;
struct msg *msghdrs;
struct user_msqid_ds *msqids;
static lck_grp_t *sysv_msg_subsys_lck_grp;
static lck_grp_attr_t *sysv_msg_subsys_lck_grp_attr;
static lck_attr_t *sysv_msg_subsys_lck_attr;
static lck_mtx_t sysv_msg_subsys_mutex;
#define SYSV_MSG_SUBSYS_LOCK() lck_mtx_lock(&sysv_msg_subsys_mutex)
#define SYSV_MSG_SUBSYS_UNLOCK() lck_mtx_unlock(&sysv_msg_subsys_mutex)
void sysv_msg_lock_init(void);
#ifdef __APPLE_API_PRIVATE
struct msginfo msginfo = {
MSGMAX,
MSGMNI,
MSGMNB,
MSGTQL,
MSGSSZ,
MSGSEG
};
#endif
__private_extern__ void
sysv_msg_lock_init( void )
{
sysv_msg_subsys_lck_grp_attr = lck_grp_attr_alloc_init();
lck_grp_attr_setstat(sysv_msg_subsys_lck_grp_attr);
sysv_msg_subsys_lck_grp = lck_grp_alloc_init("sysv_msg_subsys_lock", sysv_msg_subsys_lck_grp_attr);
sysv_msg_subsys_lck_attr = lck_attr_alloc_init();
lck_mtx_init(&sysv_msg_subsys_mutex, sysv_msg_subsys_lck_grp, sysv_msg_subsys_lck_attr);
}
static __inline__ user_time_t
sysv_msgtime(void)
{
struct timeval tv;
microtime(&tv);
return (tv.tv_sec);
}
static void
msqid_ds_64to32(struct user_msqid_ds *in, struct msqid_ds *out)
{
out->msg_perm = in->msg_perm;
out->msg_qnum = in->msg_qnum;
out->msg_cbytes = in->msg_cbytes;
out->msg_qbytes = in->msg_qbytes;
out->msg_lspid = in->msg_lspid;
out->msg_lrpid = in->msg_lrpid;
out->msg_stime = in->msg_stime;
out->msg_rtime = in->msg_rtime;
out->msg_ctime = in->msg_ctime;
}
static void
msqid_ds_32to64(struct msqid_ds *in, struct user_msqid_ds *out)
{
out->msg_ctime = in->msg_ctime;
out->msg_rtime = in->msg_rtime;
out->msg_stime = in->msg_stime;
out->msg_lrpid = in->msg_lrpid;
out->msg_lspid = in->msg_lspid;
out->msg_qbytes = in->msg_qbytes;
out->msg_cbytes = in->msg_cbytes;
out->msg_qnum = in->msg_qnum;
out->msg_perm = in->msg_perm;
}
void
msginit(__unused void *dummy)
{
static int initted = 0;
register int i;
if (initted)
return;
initted = 1;
msgpool = (char *)_MALLOC(msginfo.msgmax, M_SHM, M_WAITOK);
MALLOC(msgmaps, struct msgmap *,
sizeof(struct msgmap) * msginfo.msgseg,
M_SHM, M_WAITOK);
MALLOC(msghdrs, struct msg *,
sizeof(struct msg) * msginfo.msgtql,
M_SHM, M_WAITOK);
MALLOC(msqids, struct user_msqid_ds *,
sizeof(struct user_msqid_ds) * msginfo.msgmni,
M_SHM, M_WAITOK);
i = 8;
while (i < 1024 && i != msginfo.msgssz)
i <<= 1;
if (i != msginfo.msgssz) {
printf("msginfo.msgssz=%d (0x%x)\n", msginfo.msgssz,
msginfo.msgssz);
panic("msginfo.msgssz not a small power of 2");
}
if (msginfo.msgseg > 32767) {
printf("msginfo.msgseg=%d\n", msginfo.msgseg);
panic("msginfo.msgseg > 32767");
}
if (msgmaps == NULL)
panic("msgmaps is NULL");
for (i = 0; i < msginfo.msgseg; i++) {
if (i > 0)
msgmaps[i-1].next = i;
msgmaps[i].next = -1;
}
free_msgmaps = 0;
nfree_msgmaps = msginfo.msgseg;
if (msghdrs == NULL)
panic("msghdrs is NULL");
for (i = 0; i < msginfo.msgtql; i++) {
msghdrs[i].msg_type = 0;
if (i > 0)
msghdrs[i-1].msg_next = &msghdrs[i];
msghdrs[i].msg_next = NULL;
}
free_msghdrs = &msghdrs[0];
if (msqids == NULL)
panic("msqids is NULL");
for (i = 0; i < msginfo.msgmni; i++) {
msqids[i].msg_qbytes = 0;
msqids[i].msg_perm.seq = 0;
}
}
int
msgsys(struct proc *p, struct msgsys_args *uap, register_t *retval)
{
if (uap->which >= sizeof(msgcalls)/sizeof(msgcalls[0]))
return (EINVAL);
return ((*msgcalls[uap->which])(p, &uap->a2, retval));
}
static void
msg_freehdr(struct msg *msghdr)
{
while (msghdr->msg_ts > 0) {
short next;
if (msghdr->msg_spot < 0 || msghdr->msg_spot >= msginfo.msgseg)
panic("msghdr->msg_spot out of range");
next = msgmaps[msghdr->msg_spot].next;
msgmaps[msghdr->msg_spot].next = free_msgmaps;
free_msgmaps = msghdr->msg_spot;
nfree_msgmaps++;
msghdr->msg_spot = next;
if (msghdr->msg_ts >= msginfo.msgssz)
msghdr->msg_ts -= msginfo.msgssz;
else
msghdr->msg_ts = 0;
}
if (msghdr->msg_spot != -1)
panic("msghdr->msg_spot != -1");
msghdr->msg_next = free_msghdrs;
free_msghdrs = msghdr;
}
int
msgctl(struct proc *p, struct msgctl_args *uap, register_t *retval)
{
int msqid = uap->msqid;
int cmd = uap->cmd;
kauth_cred_t cred = kauth_cred_get();
int rval, eval;
struct user_msqid_ds msqbuf;
struct user_msqid_ds *msqptr;
struct user_msqid_ds umsds;
SYSV_MSG_SUBSYS_LOCK();
msginit( 0);
#ifdef MSG_DEBUG_OK
printf("call to msgctl(%d, %d, 0x%qx)\n", msqid, cmd, uap->buf);
#endif
AUDIT_ARG(svipc_cmd, cmd);
AUDIT_ARG(svipc_id, msqid);
msqid = IPCID_TO_IX(msqid);
if (msqid < 0 || msqid >= msginfo.msgmni) {
#ifdef MSG_DEBUG_OK
printf("msqid (%d) out of range (0<=msqid<%d)\n", msqid,
msginfo.msgmni);
#endif
eval = EINVAL;
goto msgctlout;
}
msqptr = &msqids[msqid];
if (msqptr->msg_qbytes == 0) {
#ifdef MSG_DEBUG_OK
printf("no such msqid\n");
#endif
eval = EINVAL;
goto msgctlout;
}
if (msqptr->msg_perm.seq != IPCID_TO_SEQ(uap->msqid)) {
#ifdef MSG_DEBUG_OK
printf("wrong sequence number\n");
#endif
eval = EINVAL;
goto msgctlout;
}
eval = 0;
rval = 0;
switch (cmd) {
case IPC_RMID:
{
struct msg *msghdr;
if ((eval = ipcperm(cred, &msqptr->msg_perm, IPC_M)))
goto msgctlout;
msghdr = msqptr->msg_first;
while (msghdr != NULL) {
struct msg *msghdr_tmp;
msqptr->msg_cbytes -= msghdr->msg_ts;
msqptr->msg_qnum--;
msghdr_tmp = msghdr;
msghdr = msghdr->msg_next;
msg_freehdr(msghdr_tmp);
}
if (msqptr->msg_cbytes != 0)
panic("msg_cbytes is messed up");
if (msqptr->msg_qnum != 0)
panic("msg_qnum is messed up");
msqptr->msg_qbytes = 0;
wakeup((caddr_t)msqptr);
}
break;
case IPC_SET:
if ((eval = ipcperm(cred, &msqptr->msg_perm, IPC_M)))
goto msgctlout;
SYSV_MSG_SUBSYS_UNLOCK();
if (IS_64BIT_PROCESS(p)) {
eval = copyin(uap->buf, &msqbuf, sizeof(struct user_msqid_ds));
} else {
eval = copyin(uap->buf, &msqbuf, sizeof(struct msqid_ds));
msqid_ds_32to64((struct msqid_ds *)&msqbuf, &msqbuf);
}
if (eval)
return(eval);
SYSV_MSG_SUBSYS_LOCK();
if (msqbuf.msg_qbytes > msqptr->msg_qbytes) {
eval = suser(cred, &p->p_acflag);
if (eval)
goto msgctlout;
}
if (msqbuf.msg_qbytes > (msglen_t)msginfo.msgmnb) {
#ifdef MSG_DEBUG_OK
printf("can't increase msg_qbytes beyond %d (truncating)\n",
msginfo.msgmnb);
#endif
msqbuf.msg_qbytes = msginfo.msgmnb;
}
if (msqbuf.msg_qbytes == 0) {
#ifdef MSG_DEBUG_OK
printf("can't reduce msg_qbytes to 0\n");
#endif
eval = EINVAL;
goto msgctlout;
}
msqptr->msg_perm.uid = msqbuf.msg_perm.uid;
msqptr->msg_perm.gid = msqbuf.msg_perm.gid;
msqptr->msg_perm.mode = (msqptr->msg_perm.mode & ~0777) |
(msqbuf.msg_perm.mode & 0777);
msqptr->msg_qbytes = msqbuf.msg_qbytes;
msqptr->msg_ctime = sysv_msgtime();
break;
case IPC_STAT:
if ((eval = ipcperm(cred, &msqptr->msg_perm, IPC_R))) {
#ifdef MSG_DEBUG_OK
printf("requester doesn't have read access\n");
#endif
goto msgctlout;
}
bcopy(msqptr, &umsds, sizeof(struct user_msqid_ds));
SYSV_MSG_SUBSYS_UNLOCK();
if (IS_64BIT_PROCESS(p)) {
eval = copyout(&umsds, uap->buf, sizeof(struct user_msqid_ds));
} else {
struct msqid_ds msqid_ds32;
msqid_ds_64to32(&umsds, &msqid_ds32);
eval = copyout(&msqid_ds32, uap->buf, sizeof(struct msqid_ds));
}
SYSV_MSG_SUBSYS_LOCK();
break;
default:
#ifdef MSG_DEBUG_OK
printf("invalid command %d\n", cmd);
#endif
eval = EINVAL;
goto msgctlout;
}
if (eval == 0)
*retval = rval;
msgctlout:
SYSV_MSG_SUBSYS_UNLOCK();
return(eval);
}
int
msgget(__unused struct proc *p, struct msgget_args *uap, register_t *retval)
{
int msqid, eval;
int key = uap->key;
int msgflg = uap->msgflg;
kauth_cred_t cred = kauth_cred_get();
struct user_msqid_ds *msqptr = NULL;
SYSV_MSG_SUBSYS_LOCK();
msginit( 0);
#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->msg_qbytes != 0 &&
msqptr->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->msg_perm, msgflg & 0700 ))) {
#ifdef MSG_DEBUG_OK
printf("requester doesn't have 0%o access\n",
msgflg & 0700);
#endif
goto msggetout;
}
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++) {
msqptr = &msqids[msqid];
if (msqptr->msg_qbytes == 0 &&
(msqptr->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->msg_perm.key = key;
msqptr->msg_perm.cuid = kauth_cred_getuid(cred);
msqptr->msg_perm.uid = kauth_cred_getuid(cred);
msqptr->msg_perm.cgid = cred->cr_gid;
msqptr->msg_perm.gid = cred->cr_gid;
msqptr->msg_perm.mode = (msgflg & 0777);
msqptr->msg_perm.seq++;
msqptr->msg_first = NULL;
msqptr->msg_last = NULL;
msqptr->msg_cbytes = 0;
msqptr->msg_qnum = 0;
msqptr->msg_qbytes = msginfo.msgmnb;
msqptr->msg_lspid = 0;
msqptr->msg_lrpid = 0;
msqptr->msg_stime = 0;
msqptr->msg_rtime = 0;
msqptr->msg_ctime = sysv_msgtime();
} else {
#ifdef MSG_DEBUG_OK
printf("didn't find it and wasn't asked to create it\n");
#endif
eval = ENOENT;
goto msggetout;
}
found:
*retval = IXSEQ_TO_IPCID(msqid, msqptr->msg_perm);
AUDIT_ARG(svipc_id, *retval);
eval = 0;
msggetout:
SYSV_MSG_SUBSYS_UNLOCK();
return(eval);
}
int
msgsnd(struct proc *p, struct msgsnd_args *uap, register_t *retval)
{
int msqid = uap->msqid;
user_addr_t user_msgp = uap->msgp;
size_t msgsz = (size_t)uap->msgsz;
int msgflg = uap->msgflg;
int segs_needed, eval;
struct user_msqid_ds *msqptr;
struct msg *msghdr;
short next;
user_long_t msgtype;
SYSV_MSG_SUBSYS_LOCK();
msginit( 0);
#ifdef MSG_DEBUG_OK
printf("call to msgsnd(%d, 0x%qx, %d, %d)\n", msqid, user_msgp, msgsz,
msgflg);
#endif
AUDIT_ARG(svipc_id, msqid);
msqid = IPCID_TO_IX(msqid);
if (msqid < 0 || msqid >= msginfo.msgmni) {
#ifdef MSG_DEBUG_OK
printf("msqid (%d) out of range (0<=msqid<%d)\n", msqid,
msginfo.msgmni);
#endif
eval = EINVAL;
goto msgsndout;
}
msqptr = &msqids[msqid];
if (msqptr->msg_qbytes == 0) {
#ifdef MSG_DEBUG_OK
printf("no such message queue id\n");
#endif
eval = EINVAL;
goto msgsndout;
}
if (msqptr->msg_perm.seq != IPCID_TO_SEQ(uap->msqid)) {
#ifdef MSG_DEBUG_OK
printf("wrong sequence number\n");
#endif
eval = EINVAL;
goto msgsndout;
}
if ((eval = ipcperm(kauth_cred_get(), &msqptr->msg_perm, IPC_W))) {
#ifdef MSG_DEBUG_OK
printf("requester doesn't have write access\n");
#endif
goto msgsndout;
}
segs_needed = (msgsz + msginfo.msgssz - 1) / msginfo.msgssz;
#ifdef MSG_DEBUG_OK
printf("msgsz=%d, msgssz=%d, segs_needed=%d\n", msgsz, msginfo.msgssz,
segs_needed);
#endif
for (;;) {
int need_more_resources = 0;
if (msgsz > msqptr->msg_qbytes) {
#ifdef MSG_DEBUG_OK
printf("msgsz > msqptr->msg_qbytes\n");
#endif
eval = EINVAL;
goto msgsndout;
}
if (msqptr->msg_perm.mode & MSG_LOCKED) {
#ifdef MSG_DEBUG_OK
printf("msqid is locked\n");
#endif
need_more_resources = 1;
}
if (msgsz + msqptr->msg_cbytes > msqptr->msg_qbytes) {
#ifdef MSG_DEBUG_OK
printf("msgsz + msg_cbytes > msg_qbytes\n");
#endif
need_more_resources = 1;
}
if (segs_needed > nfree_msgmaps) {
#ifdef MSG_DEBUG_OK
printf("segs_needed > nfree_msgmaps\n");
#endif
need_more_resources = 1;
}
if (free_msghdrs == NULL) {
#ifdef MSG_DEBUG_OK
printf("no more msghdrs\n");
#endif
need_more_resources = 1;
}
if (need_more_resources) {
int we_own_it;
if ((msgflg & IPC_NOWAIT) != 0) {
#ifdef MSG_DEBUG_OK
printf("need more resources but caller doesn't want to wait\n");
#endif
eval = EAGAIN;
goto msgsndout;
}
if ((msqptr->msg_perm.mode & MSG_LOCKED) != 0) {
#ifdef MSG_DEBUG_OK
printf("we don't own the user_msqid_ds\n");
#endif
we_own_it = 0;
} else {
#ifdef MSG_DEBUG_OK
printf("we own the user_msqid_ds\n");
#endif
msqptr->msg_perm.mode |= MSG_LOCKED;
we_own_it = 1;
}
#ifdef MSG_DEBUG_OK
printf("goodnight\n");
#endif
eval = msleep((caddr_t)msqptr, &sysv_msg_subsys_mutex, (PZERO - 4) | PCATCH,
"msgwait", 0);
#ifdef MSG_DEBUG_OK
printf("good morning, eval=%d\n", eval);
#endif
if (we_own_it)
msqptr->msg_perm.mode &= ~MSG_LOCKED;
if (eval != 0) {
#ifdef MSG_DEBUG_OK
printf("msgsnd: interrupted system call\n");
#endif
eval = EINTR;
goto msgsndout;
}
if (msqptr->msg_qbytes == 0) {
#ifdef MSG_DEBUG_OK
printf("msqid deleted\n");
#endif
#ifdef EIDRM
eval = EIDRM;
#else
eval = EINVAL;
#endif
goto msgsndout;
}
} else {
#ifdef MSG_DEBUG_OK
printf("got all the resources that we need\n");
#endif
break;
}
}
if (msqptr->msg_perm.mode & MSG_LOCKED)
panic("msg_perm.mode & MSG_LOCKED");
if (segs_needed > nfree_msgmaps)
panic("segs_needed > nfree_msgmaps");
if (msgsz + msqptr->msg_cbytes > msqptr->msg_qbytes)
panic("msgsz + msg_cbytes > msg_qbytes");
if (free_msghdrs == NULL)
panic("no more msghdrs");
if ((msqptr->msg_perm.mode & MSG_LOCKED) != 0)
panic("user_msqid_ds is already locked");
msqptr->msg_perm.mode |= MSG_LOCKED;
msghdr = free_msghdrs;
free_msghdrs = msghdr->msg_next;
msghdr->msg_spot = -1;
msghdr->msg_ts = msgsz;
while (segs_needed > 0) {
if (nfree_msgmaps <= 0)
panic("not enough msgmaps");
if (free_msgmaps == -1)
panic("nil free_msgmaps");
next = free_msgmaps;
if (next <= -1)
panic("next too low #1");
if (next >= msginfo.msgseg)
panic("next out of range #1");
#ifdef MSG_DEBUG_OK
printf("allocating segment %d to message\n", next);
#endif
free_msgmaps = msgmaps[next].next;
nfree_msgmaps--;
msgmaps[next].next = msghdr->msg_spot;
msghdr->msg_spot = next;
segs_needed--;
}
if (IS_64BIT_PROCESS(p)) {
SYSV_MSG_SUBSYS_UNLOCK();
eval = copyin(user_msgp, &msgtype, sizeof(msgtype));
SYSV_MSG_SUBSYS_LOCK();
msghdr->msg_type = CAST_DOWN(long,msgtype);
user_msgp = user_msgp + sizeof(msgtype);
} else {
SYSV_MSG_SUBSYS_UNLOCK();
eval = copyin(user_msgp, &msghdr->msg_type, sizeof(long));
SYSV_MSG_SUBSYS_LOCK();
user_msgp = user_msgp + sizeof(long);
}
if (eval != 0) {
#ifdef MSG_DEBUG_OK
printf("error %d copying the message type\n", eval);
#endif
msg_freehdr(msghdr);
msqptr->msg_perm.mode &= ~MSG_LOCKED;
wakeup((caddr_t)msqptr);
goto msgsndout;
}
if (msghdr->msg_type < 1) {
msg_freehdr(msghdr);
msqptr->msg_perm.mode &= ~MSG_LOCKED;
wakeup((caddr_t)msqptr);
#ifdef MSG_DEBUG_OK
printf("mtype (%d) < 1\n", msghdr->msg_type);
#endif
eval = EINVAL;
goto msgsndout;
}
next = msghdr->msg_spot;
while (msgsz > 0) {
size_t tlen;
if (msgsz > (size_t)msginfo.msgssz)
tlen = msginfo.msgssz;
else
tlen = msgsz;
if (next <= -1)
panic("next too low #2");
if (next >= msginfo.msgseg)
panic("next out of range #2");
SYSV_MSG_SUBSYS_UNLOCK();
eval = copyin(user_msgp, &msgpool[next * msginfo.msgssz], tlen);
SYSV_MSG_SUBSYS_LOCK();
if (eval != 0) {
#ifdef MSG_DEBUG_OK
printf("error %d copying in message segment\n", eval);
#endif
msg_freehdr(msghdr);
msqptr->msg_perm.mode &= ~MSG_LOCKED;
wakeup((caddr_t)msqptr);
goto msgsndout;
}
msgsz -= tlen;
user_msgp = user_msgp + tlen;
next = msgmaps[next].next;
}
if (next != -1)
panic("didn't use all the msg segments");
msqptr->msg_perm.mode &= ~MSG_LOCKED;
if (msqptr->msg_qbytes == 0) {
msg_freehdr(msghdr);
wakeup((caddr_t)msqptr);
#ifdef EIDRM
eval = EIDRM;
#else
eval = EINVAL;
#endif
goto msgsndout;
}
if (msqptr->msg_first == NULL) {
msqptr->msg_first = msghdr;
msqptr->msg_last = msghdr;
} else {
msqptr->msg_last->msg_next = msghdr;
msqptr->msg_last = msghdr;
}
msqptr->msg_last->msg_next = NULL;
msqptr->msg_cbytes += msghdr->msg_ts;
msqptr->msg_qnum++;
msqptr->msg_lspid = p->p_pid;
msqptr->msg_stime = sysv_msgtime();
wakeup((caddr_t)msqptr);
*retval = 0;
eval = 0;
msgsndout:
SYSV_MSG_SUBSYS_UNLOCK();
return(eval);
}
int
msgrcv(struct proc *p, struct msgrcv_args *uap, user_ssize_t *retval)
{
int msqid = uap->msqid;
user_addr_t user_msgp = uap->msgp;
size_t msgsz = (size_t)uap->msgsz;
long msgtyp = (long)uap->msgtyp;
int msgflg = uap->msgflg;
size_t len;
struct user_msqid_ds *msqptr;
struct msg *msghdr;
int eval;
short next;
user_long_t msgtype;
long msg_type_long;
SYSV_MSG_SUBSYS_LOCK();
msginit( 0);
#ifdef MSG_DEBUG_OK
printf("call to msgrcv(%d, 0x%qx, %d, %ld, %d)\n", msqid, user_msgp,
msgsz, msgtyp, msgflg);
#endif
AUDIT_ARG(svipc_id, msqid);
msqid = IPCID_TO_IX(msqid);
if (msqid < 0 || msqid >= msginfo.msgmni) {
#ifdef MSG_DEBUG_OK
printf("msqid (%d) out of range (0<=msqid<%d)\n", msqid,
msginfo.msgmni);
#endif
eval = EINVAL;
goto msgrcvout;
}
msqptr = &msqids[msqid];
if (msqptr->msg_qbytes == 0) {
#ifdef MSG_DEBUG_OK
printf("no such message queue id\n");
#endif
eval = EINVAL;
goto msgrcvout;
}
if (msqptr->msg_perm.seq != IPCID_TO_SEQ(uap->msqid)) {
#ifdef MSG_DEBUG_OK
printf("wrong sequence number\n");
#endif
eval = EINVAL;
goto msgrcvout;
}
if ((eval = ipcperm(kauth_cred_get(), &msqptr->msg_perm, IPC_R))) {
#ifdef MSG_DEBUG_OK
printf("requester doesn't have read access\n");
#endif
goto msgrcvout;
}
msghdr = NULL;
while (msghdr == NULL) {
if (msgtyp == 0) {
msghdr = msqptr->msg_first;
if (msghdr != NULL) {
if (msgsz < msghdr->msg_ts &&
(msgflg & MSG_NOERROR) == 0) {
#ifdef MSG_DEBUG_OK
printf("first message on the queue is too big (want %d, got %d)\n",
msgsz, msghdr->msg_ts);
#endif
eval = E2BIG;
goto msgrcvout;
}
if (msqptr->msg_first == msqptr->msg_last) {
msqptr->msg_first = NULL;
msqptr->msg_last = NULL;
} else {
msqptr->msg_first = msghdr->msg_next;
if (msqptr->msg_first == NULL)
panic("msg_first/last messed up #1");
}
}
} else {
struct msg *previous;
struct msg **prev;
previous = NULL;
prev = &(msqptr->msg_first);
while ((msghdr = *prev) != NULL) {
if (msgtyp == msghdr->msg_type ||
msghdr->msg_type <= -msgtyp) {
#ifdef MSG_DEBUG_OK
printf("found message type %d, requested %d\n",
msghdr->msg_type, msgtyp);
#endif
if (msgsz < msghdr->msg_ts &&
(msgflg & MSG_NOERROR) == 0) {
#ifdef MSG_DEBUG_OK
printf("requested message on the queue is too big (want %d, got %d)\n",
msgsz, msghdr->msg_ts);
#endif
eval = E2BIG;
goto msgrcvout;
}
*prev = msghdr->msg_next;
if (msghdr == msqptr->msg_last) {
if (previous == NULL) {
if (prev !=
&msqptr->msg_first)
panic("msg_first/last messed up #2");
msqptr->msg_first =
NULL;
msqptr->msg_last =
NULL;
} else {
if (prev ==
&msqptr->msg_first)
panic("msg_first/last messed up #3");
msqptr->msg_last =
previous;
}
}
break;
}
previous = msghdr;
prev = &(msghdr->msg_next);
}
}
if (msghdr != NULL)
break;
if ((msgflg & IPC_NOWAIT) != 0) {
#ifdef MSG_DEBUG_OK
printf("no appropriate message found (msgtyp=%d)\n",
msgtyp);
#endif
#ifdef ENOMSG
eval = ENOMSG;
#else
eval = EAGAIN;
#endif
goto msgrcvout;
}
#ifdef MSG_DEBUG_OK
printf("msgrcv: goodnight\n");
#endif
eval = msleep((caddr_t)msqptr, &sysv_msg_subsys_mutex, (PZERO - 4) | PCATCH, "msgwait",
0);
#ifdef MSG_DEBUG_OK
printf("msgrcv: good morning (eval=%d)\n", eval);
#endif
if (eval != 0) {
#ifdef MSG_DEBUG_OK
printf("msgsnd: interrupted system call\n");
#endif
eval = EINTR;
goto msgrcvout;
}
if (msqptr->msg_qbytes == 0 ||
msqptr->msg_perm.seq != IPCID_TO_SEQ(uap->msqid)) {
#ifdef MSG_DEBUG_OK
printf("msqid deleted\n");
#endif
#ifdef EIDRM
eval = EIDRM;
#else
eval = EINVAL;
#endif
goto msgrcvout;
}
}
msqptr->msg_cbytes -= msghdr->msg_ts;
msqptr->msg_qnum--;
msqptr->msg_lrpid = p->p_pid;
msqptr->msg_rtime = sysv_msgtime();
#ifdef MSG_DEBUG_OK
printf("found a message, msgsz=%d, msg_ts=%d\n", msgsz,
msghdr->msg_ts);
#endif
if (msgsz > msghdr->msg_ts)
msgsz = msghdr->msg_ts;
if (IS_64BIT_PROCESS(p)) {
msgtype = msghdr->msg_type;
SYSV_MSG_SUBSYS_UNLOCK();
eval = copyout(&msgtype, user_msgp, sizeof(msgtype));
SYSV_MSG_SUBSYS_LOCK();
user_msgp = user_msgp + sizeof(msgtype);
} else {
msg_type_long = msghdr->msg_type;
SYSV_MSG_SUBSYS_UNLOCK();
eval = copyout(&msg_type_long, user_msgp, sizeof(long));
SYSV_MSG_SUBSYS_LOCK();
user_msgp = user_msgp + sizeof(long);
}
if (eval != 0) {
#ifdef MSG_DEBUG_OK
printf("error (%d) copying out message type\n", eval);
#endif
msg_freehdr(msghdr);
wakeup((caddr_t)msqptr);
goto msgrcvout;
}
next = msghdr->msg_spot;
for (len = 0; len < msgsz; len += msginfo.msgssz) {
size_t tlen;
if (msgsz > (size_t)msginfo.msgssz)
tlen = msginfo.msgssz;
else
tlen = msgsz;
if (next <= -1)
panic("next too low #3");
if (next >= msginfo.msgseg)
panic("next out of range #3");
SYSV_MSG_SUBSYS_UNLOCK();
eval = copyout(&msgpool[next * msginfo.msgssz],
user_msgp, tlen);
SYSV_MSG_SUBSYS_LOCK();
if (eval != 0) {
#ifdef MSG_DEBUG_OK
printf("error (%d) copying out message segment\n",
eval);
#endif
msg_freehdr(msghdr);
wakeup((caddr_t)msqptr);
goto msgrcvout;
}
user_msgp = user_msgp + tlen;
next = msgmaps[next].next;
}
msg_freehdr(msghdr);
wakeup((caddr_t)msqptr);
*retval = msgsz;
eval = 0;
msgrcvout:
SYSV_MSG_SUBSYS_UNLOCK();
return(eval);
}
static int
IPCS_msg_sysctl(__unused struct sysctl_oid *oidp, __unused void *arg1,
__unused int arg2, struct sysctl_req *req)
{
int error;
int cursor;
union {
struct IPCS_command u32;
struct user_IPCS_command u64;
} ipcs;
struct msqid_ds msqid_ds32;
void *msqid_dsp;
size_t ipcs_sz = sizeof(struct user_IPCS_command);
size_t msqid_ds_sz = sizeof(struct user_msqid_ds);
struct proc *p = current_proc();
if (!IS_64BIT_PROCESS(p)) {
ipcs_sz = sizeof(struct IPCS_command);
msqid_ds_sz = sizeof(struct msqid_ds);
}
if ((error = SYSCTL_IN(req, &ipcs, ipcs_sz)) != 0) {
return(error);
}
if (!IS_64BIT_PROCESS(p))
ipcs.u64.ipcs_data = CAST_USER_ADDR_T(ipcs.u32.ipcs_data);
if (ipcs.u64.ipcs_magic != IPCS_MAGIC) {
return(EINVAL);
}
SYSV_MSG_SUBSYS_LOCK();
switch(ipcs.u64.ipcs_op) {
case IPCS_MSG_CONF:
if (ipcs.u64.ipcs_datalen != sizeof(struct msginfo)) {
error = ERANGE;
break;
}
if (ipcs.u64.ipcs_cursor != 0) {
error = EINVAL;
break;
}
SYSV_MSG_SUBSYS_UNLOCK();
error = copyout(&msginfo, ipcs.u64.ipcs_data, ipcs.u64.ipcs_datalen);
SYSV_MSG_SUBSYS_LOCK();
break;
case IPCS_MSG_ITER:
msginit( 0);
cursor = ipcs.u64.ipcs_cursor;
if (cursor < 0 || cursor >= msginfo.msgmni) {
error = ERANGE;
break;
}
if (ipcs.u64.ipcs_datalen != (int)msqid_ds_sz) {
error = ENOMEM;
break;
}
for( ; cursor < msginfo.msgmni; cursor++) {
if (msqids[cursor].msg_qbytes != 0)
break;
continue;
}
if (cursor == msginfo.msgmni) {
error = ENOENT;
break;
}
msqid_dsp = &msqids[cursor];
if (!IS_64BIT_PROCESS(p)) {
msqid_ds_64to32(msqid_dsp, &msqid_ds32);
msqid_dsp = &msqid_ds32;
}
SYSV_MSG_SUBSYS_UNLOCK();
error = copyout(msqid_dsp, ipcs.u64.ipcs_data, ipcs.u64.ipcs_datalen);
if (!error) {
ipcs.u64.ipcs_cursor = cursor + 1;
if (!IS_64BIT_PROCESS(p))
ipcs.u32.ipcs_data = CAST_DOWN(void *,ipcs.u64.ipcs_data);
error = SYSCTL_OUT(req, &ipcs, ipcs_sz);
}
SYSV_MSG_SUBSYS_LOCK();
break;
default:
error = EINVAL;
break;
}
SYSV_MSG_SUBSYS_UNLOCK();
return(error);
}
SYSCTL_DECL(_kern_sysv_ipcs);
SYSCTL_PROC(_kern_sysv_ipcs, OID_AUTO, msg, CTLFLAG_RW|CTLFLAG_ANYBODY,
0, 0, IPCS_msg_sysctl,
"S,IPCS_msg_command",
"ipcs msg command interface");