/*
* Get the access information from the cache or callup to the mountd
* to get and cache the access information in the kernel.
*/
int
nfsauth_cache_get(struct exportinfo *exi, struct svc_req *req, int flavor)
{
struct netbuf addr;
struct netbuf *claddr;
struct auth_cache **head;
struct auth_cache *ap;
int access;
varg_t varg = {0};
nfsauth_res_t res = {0};
XDR xdrs_a;
XDR xdrs_r;
size_t absz;
caddr_t abuf;
size_t rbsz = (size_t)(BYTES_PER_XDR_UNIT * 2);
char result[BYTES_PER_XDR_UNIT * 2] = {0};
caddr_t rbuf = (caddr_t)&result;
int last = 0;
door_arg_t da;
door_info_t di;
door_handle_t dh;
uint_t ntries = 0;
/*
* Now check whether this client already
* has an entry for this flavor in the cache
* for this export.
* Get the caller's address, mask off the
* parts of the address that do not identify
* the host (port number, etc), and then hash
* it to find the chain of cache entries.
*/
claddr = svc_getrpccaller(req->rq_xprt);
addr = *claddr;
addr.buf = kmem_alloc(addr.len, KM_SLEEP);
bcopy(claddr->buf, addr.buf, claddr->len);
addrmask(&addr, svc_getaddrmask(req->rq_xprt));
head = &exi->exi_cache[hash(&addr)];
rw_enter(&exi->exi_cache_lock, RW_READER);
for (ap = *head; ap; ap = ap->auth_next) {
if (EQADDR(&addr, &ap->auth_addr) && flavor == ap->auth_flavor)
break;
}
if (ap) { /* cache hit */
access = ap->auth_access;
ap->auth_time = gethrestime_sec();
nfsauth_cache_hit++;
}
rw_exit(&exi->exi_cache_lock);
if (ap) {
kmem_free(addr.buf, addr.len);
return (access);
}
nfsauth_cache_miss++;
/*
* No entry in the cache for this client/flavor
* so we need to call the nfsauth service in the
* mount daemon.
*/
retry:
mutex_enter(&mountd_lock);
dh = mountd_dh;
if (dh)
door_ki_hold(dh);
mutex_exit(&mountd_lock);
if (dh == NULL) {
/*
* The rendezvous point has not been established yet !
* This could mean that either mountd(1m) has not yet
* been started or that _this_ routine nuked the door
* handle after receiving an EINTR for a REVOKED door.
*
* Returning NFSAUTH_DROP will cause the NFS client
* to retransmit the request, so let's try to be more
* rescillient and attempt for ntries before we bail.
*/
if (++ntries % NFSAUTH_DR_TRYCNT) {
delay(hz);
goto retry;
}
sys_log("nfsauth: mountd has not established door");
kmem_free(addr.buf, addr.len);
return (NFSAUTH_DROP);
}
ntries = 0;
varg.vers = V_PROTO;
varg.arg_u.arg.cmd = NFSAUTH_ACCESS;
varg.arg_u.arg.areq.req_client.n_len = addr.len;
varg.arg_u.arg.areq.req_client.n_bytes = addr.buf;
varg.arg_u.arg.areq.req_netid = svc_getnetid(req->rq_xprt);
varg.arg_u.arg.areq.req_path = exi->exi_export.ex_path;
varg.arg_u.arg.areq.req_flavor = flavor;
/*
* Setup the XDR stream for encoding the arguments. Notice that
* in addition to the args having variable fields (req_netid and
* req_path), the argument data structure is itself versioned,
* so we need to make sure we can size the arguments buffer
* appropriately to encode all the args. If we can't get sizing
* info _or_ properly encode the arguments, there's really no
* point in continuting, so we fail the request.
*/
DTRACE_PROBE1(nfsserv__func__nfsauth__varg, varg_t *, &varg);
if ((absz = xdr_sizeof(xdr_varg, (void *)&varg)) == 0) {
door_ki_rele(dh);
kmem_free(addr.buf, addr.len);
return (NFSAUTH_DENIED);
}
abuf = (caddr_t)kmem_alloc(absz, KM_SLEEP);
xdrmem_create(&xdrs_a, abuf, absz, XDR_ENCODE);
if (!xdr_varg(&xdrs_a, &varg)) {
door_ki_rele(dh);
goto fail;
}
XDR_DESTROY(&xdrs_a);
/*
* The result (nfsauth_res_t) is always two int's, so we don't
* have to dynamically size (or allocate) the results buffer.
* Now that we've got what we need, we prep the door arguments
* and place the call.
*/
da.data_ptr = (char *)abuf;
da.data_size = absz;
da.desc_ptr = NULL;
da.desc_num = 0;
da.rbuf = (char *)rbuf;
da.rsize = rbsz;
switch (door_ki_upcall_limited(dh, &da, NULL, SIZE_MAX, 0)) {
case 0: /* Success */
if (da.data_ptr != da.rbuf && da.data_size == 0) {
/*
* The door_return that contained the data
* failed ! We're here because of the 2nd
* door_return (w/o data) such that we can
* get control of the thread (and exit
* gracefully).
*/
DTRACE_PROBE1(nfsserv__func__nfsauth__door__nil,
door_arg_t *, &da);
door_ki_rele(dh);
goto fail;
} else if (rbuf != da.rbuf) {
/*
* nfscmd_send(arg, result)
*
* Send a command to the daemon listening on the door. The result is
* returned in the result pointer if the function return value is
* NFSCMD_ERR_SUCCESS. Otherwise it is the error value.
*/
int
nfscmd_send(nfscmd_arg_t *arg, nfscmd_res_t *res)
{
door_handle_t dh;
door_arg_t da;
door_info_t di;
int ntries = 0;
int last = 0;
retry:
mutex_enter(&nfscmd_lock);
dh = nfscmd_dh;
if (dh != NULL)
door_ki_hold(dh);
mutex_exit(&nfscmd_lock);
if (dh == NULL) {
/*
* The rendezvous point has not been established yet !
* This could mean that either mountd(1m) has not yet
* been started or that _this_ routine nuked the door
* handle after receiving an EINTR for a REVOKED door.
*
* Returning NFSAUTH_DROP will cause the NFS client
* to retransmit the request, so let's try to be more
* rescillient and attempt for ntries before we bail.
*/
if (++ntries % NFSCMD_DR_TRYCNT) {
delay(hz);
goto retry;
}
return (NFSCMD_ERR_DROP);
}
da.data_ptr = (char *)arg;
da.data_size = sizeof (nfscmd_arg_t);
da.desc_ptr = NULL;
da.desc_num = 0;
da.rbuf = (char *)res;
da.rsize = sizeof (nfscmd_res_t);
switch (door_ki_upcall(dh, &da)) {
case 0:
/* Success */
break;
case EAGAIN:
/* Need to retry a couple of times */
door_ki_rele(dh);
delay(hz);
goto retry;
/* NOTREACHED */
case EINTR:
if (!door_ki_info(dh, &di)) {
if (di.di_attributes & DOOR_REVOKED) {
/*
* The server barfed and revoked
* the (existing) door on us; we
* want to wait to give smf(5) a
* chance to restart mountd(1m)
* and establish a new door handle.
*/
mutex_enter(&nfscmd_lock);
if (dh == nfscmd_dh)
nfscmd_dh = NULL;
mutex_exit(&nfscmd_lock);
door_ki_rele(dh);
delay(hz);
goto retry;
}
/*
* If the door was _not_ revoked on us,
* then more than likely we took an INTR,
* so we need to fail the operation.
*/
door_ki_rele(dh);
}
/*
* The only failure that can occur from getting
* the door info is EINVAL, so we let the code
* below handle it.
*/
/* FALLTHROUGH */
case EBADF:
case EINVAL:
default:
/*
* If we have a stale door handle, give smf a last
* chance to start it by sleeping for a little bit.
* If we're still hosed, we'll fail the call.
*
* Since we're going to reacquire the door handle
* upon the retry, we opt to sleep for a bit and
* _not_ to clear mountd_dh. If mountd restarted
* and was able to set mountd_dh, we should see
* the new instance; if not, we won't get caught
* up in the retry/DELAY loop.
*/
door_ki_rele(dh);
if (!last) {
delay(hz);
last++;
goto retry;
}
res->error = NFSCMD_ERR_FAIL;
break;
}
return (res->error);
}
/*
* Callup to the mountd to get access information in the kernel.
*/
static bool_t
nfsauth_retrieve(struct exportinfo *exi, char *req_netid, int flavor,
struct netbuf *addr, int *access, uid_t clnt_uid, gid_t clnt_gid,
uint_t clnt_gids_cnt, const gid_t *clnt_gids, uid_t *srv_uid,
gid_t *srv_gid, uint_t *srv_gids_cnt, gid_t **srv_gids)
{
varg_t varg = {0};
nfsauth_res_t res = {0};
XDR xdrs;
size_t absz;
caddr_t abuf;
int last = 0;
door_arg_t da;
door_info_t di;
door_handle_t dh;
uint_t ntries = 0;
/*
* No entry in the cache for this client/flavor
* so we need to call the nfsauth service in the
* mount daemon.
*/
varg.vers = V_PROTO;
varg.arg_u.arg.cmd = NFSAUTH_ACCESS;
varg.arg_u.arg.areq.req_client.n_len = addr->len;
varg.arg_u.arg.areq.req_client.n_bytes = addr->buf;
varg.arg_u.arg.areq.req_netid = req_netid;
varg.arg_u.arg.areq.req_path = exi->exi_export.ex_path;
varg.arg_u.arg.areq.req_flavor = flavor;
varg.arg_u.arg.areq.req_clnt_uid = clnt_uid;
varg.arg_u.arg.areq.req_clnt_gid = clnt_gid;
varg.arg_u.arg.areq.req_clnt_gids.len = clnt_gids_cnt;
varg.arg_u.arg.areq.req_clnt_gids.val = (gid_t *)clnt_gids;
DTRACE_PROBE1(nfsserv__func__nfsauth__varg, varg_t *, &varg);
/*
* Setup the XDR stream for encoding the arguments. Notice that
* in addition to the args having variable fields (req_netid and
* req_path), the argument data structure is itself versioned,
* so we need to make sure we can size the arguments buffer
* appropriately to encode all the args. If we can't get sizing
* info _or_ properly encode the arguments, there's really no
* point in continuting, so we fail the request.
*/
if ((absz = xdr_sizeof(xdr_varg, &varg)) == 0) {
*access = NFSAUTH_DENIED;
return (FALSE);
}
abuf = (caddr_t)kmem_alloc(absz, KM_SLEEP);
xdrmem_create(&xdrs, abuf, absz, XDR_ENCODE);
if (!xdr_varg(&xdrs, &varg)) {
XDR_DESTROY(&xdrs);
goto fail;
}
XDR_DESTROY(&xdrs);
/*
* Prepare the door arguments
*
* We don't know the size of the message the daemon
* will pass back to us. By setting rbuf to NULL,
* we force the door code to allocate a buf of the
* appropriate size. We must set rsize > 0, however,
* else the door code acts as if no response was
* expected and doesn't pass the data to us.
*/
da.data_ptr = (char *)abuf;
da.data_size = absz;
da.desc_ptr = NULL;
da.desc_num = 0;
da.rbuf = NULL;
da.rsize = 1;
retry:
mutex_enter(&mountd_lock);
dh = mountd_dh;
if (dh != NULL)
door_ki_hold(dh);
mutex_exit(&mountd_lock);
if (dh == NULL) {
/*
* The rendezvous point has not been established yet!
* This could mean that either mountd(1m) has not yet
* been started or that _this_ routine nuked the door
* handle after receiving an EINTR for a REVOKED door.
*
* Returning NFSAUTH_DROP will cause the NFS client
* to retransmit the request, so let's try to be more
* rescillient and attempt for ntries before we bail.
*/
if (++ntries % NFSAUTH_DR_TRYCNT) {
delay(hz);
goto retry;
}
kmem_free(abuf, absz);
sys_log("nfsauth: mountd has not established door");
*access = NFSAUTH_DROP;
return (FALSE);
}
ntries = 0;
/*
* Now that we've got what we need, place the call.
*/
switch (door_ki_upcall_limited(dh, &da, NULL, SIZE_MAX, 0)) {
case 0: /* Success */
door_ki_rele(dh);
if (da.data_ptr == NULL && da.data_size == 0) {
/*
* The door_return that contained the data
* failed! We're here because of the 2nd
* door_return (w/o data) such that we can
* get control of the thread (and exit
* gracefully).
*/
DTRACE_PROBE1(nfsserv__func__nfsauth__door__nil,
door_arg_t *, &da);
goto fail;
}
break;
case EAGAIN:
/*
* Server out of resources; back off for a bit
*/
door_ki_rele(dh);
delay(hz);
goto retry;
/* NOTREACHED */
case EINTR:
if (!door_ki_info(dh, &di)) {
door_ki_rele(dh);
if (di.di_attributes & DOOR_REVOKED) {
/*
* The server barfed and revoked
* the (existing) door on us; we
* want to wait to give smf(5) a
* chance to restart mountd(1m)
* and establish a new door handle.
*/
mutex_enter(&mountd_lock);
if (dh == mountd_dh) {
door_ki_rele(mountd_dh);
mountd_dh = NULL;
}
mutex_exit(&mountd_lock);
delay(hz);
goto retry;
}
/*
* If the door was _not_ revoked on us,
* then more than likely we took an INTR,
* so we need to fail the operation.
*/
goto fail;
}
/*
* The only failure that can occur from getting
* the door info is EINVAL, so we let the code
* below handle it.
*/
/* FALLTHROUGH */
case EBADF:
case EINVAL:
default:
/*
* If we have a stale door handle, give smf a last
* chance to start it by sleeping for a little bit.
* If we're still hosed, we'll fail the call.
*
* Since we're going to reacquire the door handle
* upon the retry, we opt to sleep for a bit and
* _not_ to clear mountd_dh. If mountd restarted
* and was able to set mountd_dh, we should see
* the new instance; if not, we won't get caught
* up in the retry/DELAY loop.
*/
door_ki_rele(dh);
if (!last) {
delay(hz);
last++;
goto retry;
}
sys_log("nfsauth: stale mountd door handle");
goto fail;
}
