/*
XDR functions to encode/decode NLM version 4 RPC arguments and results.
*/
#include <linux/types.h>
#include <linux/sunrpc/xdr.h>
#include <linux/sunrpc/clnt.h>
#include <linux/sunrpc/stats.h>
#include <linux/lockd/lockd.h>
#define NLMDBG_FACILITY NLMDBG_XDR
#if (NLMCLNT_OHSIZE > XDR_MAX_NETOBJ)
# error "NLM host name cannot be larger than XDR_MAX_NETOBJ!"
#endif
#if (NLMCLNT_OHSIZE > NLM_MAXSTRLEN)
# error "NLM host name cannot be larger than NLM's maximum string length!"
#endif
/*
* Declare the space requirements for NLM arguments and replies as
* number of 32bit-words
*/
#define NLM4_void_sz (0)
#define NLM4_cookie_sz (1+(NLM_MAXCOOKIELEN>>2))
#define NLM4_caller_sz (1+(NLMCLNT_OHSIZE>>2))
#define NLM4_owner_sz (1+(NLMCLNT_OHSIZE>>2))
#define NLM4_fhandle_sz (1+(NFS3_FHSIZE>>2))
#define NLM4_lock_sz (5+NLM4_caller_sz+NLM4_owner_sz+NLM4_fhandle_sz)
#define NLM4_holder_sz (6+NLM4_owner_sz)
#define NLM4_testargs_sz (NLM4_cookie_sz+1+NLM4_lock_sz)
#define NLM4_lockargs_sz (NLM4_cookie_sz+4+NLM4_lock_sz)
#define NLM4_cancargs_sz (NLM4_cookie_sz+2+NLM4_lock_sz)
#define NLM4_unlockargs_sz (NLM4_cookie_sz+NLM4_lock_sz)
#define NLM4_testres_sz (NLM4_cookie_sz+1+NLM4_holder_sz)
#define NLM4_res_sz (NLM4_cookie_sz+1)
#define NLM4_norep_sz (0)
static s64 loff_t_to_s64(loff_t offset)
{
s64 res;
if (offset >= NLM4_OFFSET_MAX)
res = NLM4_OFFSET_MAX;
else if (offset <= -NLM4_OFFSET_MAX)
res = -NLM4_OFFSET_MAX;
else
res = offset;
return res;
}
static void nlm4_compute_offsets(const struct nlm_lock *lock,
u64 *l_offset, u64 *l_len)
{
const struct file_lock *fl = &lock->fl;
*l_offset = loff_t_to_s64(fl->fl_start);
if (fl->fl_end == OFFSET_MAX)
*l_len = 0;
else
*l_len = loff_t_to_s64(fl->fl_end - fl->fl_start + 1);
}
/*
* Handle decode buffer overflows out-of-line.
*/
static void print_overflow_msg(const char *func, const struct xdr_stream *xdr)
{
dprintk("lockd: %s prematurely hit the end of our receive buffer. "
"Remaining buffer length is %tu words.\n",
func, xdr->end - xdr->p);
}
/*
* Encode/decode NLMv4 basic data types
*
* Basic NLMv4 data types are defined in Appendix II, section 6.1.4
* of RFC 1813: "NFS Version 3 Protocol Specification" and in Chapter
* 10 of X/Open's "Protocols for Interworking: XNFS, Version 3W".
*
* Not all basic data types have their own encoding and decoding
* functions. For run-time efficiency, some data types are encoded
* or decoded inline.
*/
static void encode_bool(struct xdr_stream *xdr, const int value)
{
__be32 *p;
p = xdr_reserve_space(xdr, 4);
*p = value ? xdr_one : xdr_zero;
}
static void encode_int32(struct xdr_stream *xdr, const s32 value)
{
__be32 *p;
p = xdr_reserve_space(xdr, 4);
*p = cpu_to_be32(value);
}
/*
* typedef opaque netobj<MAXNETOBJ_SZ>
*/
static void encode_netobj(struct xdr_stream *xdr,
const u8 *data, const unsigned int length)
{
__be32 *p;
p = xdr_reserve_space(xdr, 4 + length);
xdr_encode_opaque(p, data, length);
}
static int decode_netobj(struct xdr_stream *xdr,
struct xdr_netobj *obj)
{
u32 length;
__be32 *p;
p = xdr_inline_decode(xdr, 4);
if (unlikely(p == NULL))
goto out_overflow;
length = be32_to_cpup(p++);
if (unlikely(length > XDR_MAX_NETOBJ))
goto out_size;
obj->len = length;
obj->data = (u8 *)p;
return 0;
out_size:
dprintk("NFS: returned netobj was too long: %u\n", length);
return -EIO;
out_overflow:
print_overflow_msg(__func__, xdr);
return -EIO;
}
/*
* netobj cookie;
*/
static void encode_cookie(struct xdr_stream *xdr,
const struct nlm_cookie *cookie)
{
encode_netobj(xdr, (u8 *)&cookie->data, cookie->len);
}
static int decode_cookie(struct xdr_stream *xdr,
struct nlm_cookie *cookie)
{
u32 length;
__be32 *p;
p = xdr_inline_decode(xdr, 4);
if (unlikely(p == NULL))
goto out_overflow;
length = be32_to_cpup(p++);
/* apparently HPUX can return empty cookies */
if (length == 0)
goto out_hpux;
if (length > NLM_MAXCOOKIELEN)
goto out_size;
p = xdr_inline_decode(xdr, length);
if (unlikely(p == NULL))
goto out_overflow;
cookie->len = length;
memcpy(cookie->data, p, length);
return 0;
out_hpux:
cookie->len = 4;
memset(cookie->data, 0, 4);
return 0;
out_size:
dprintk("NFS: returned cookie was too long: %u\n", length);
return -EIO;
out_overflow:
print_overflow_msg(__func__, xdr);
return -EIO;
}
/*
* netobj fh;
*/
static void encode_fh(struct xdr_stream *xdr, const struct nfs_fh *fh)
{
encode_netobj(xdr, (u8 *)&fh->data, fh->size);
}
/*
* enum nlm4_stats {
* NLM4_GRANTED = 0,
* NLM4_DENIED = 1,
* NLM4_DENIED_NOLOCKS = 2,
* NLM4_BLOCKED = 3,
* NLM4_DENIED_GRACE_PERIOD = 4,
* NLM4_DEADLCK = 5,
* NLM4_ROFS = 6,
* NLM4_STALE_FH = 7,
* NLM4_FBIG = 8,
* NLM4_FAILED = 9
* };
*
* struct nlm4_stat {
* nlm4_stats stat;
* };
*
* NB: we don't swap bytes for the NLM status values. The upper
* layers deal directly with the status value in network byte
* order.
*/
static void encode_nlm4_stat(struct xdr_stream *xdr,
const __be32 stat)
{
__be32 *p;
BUG_ON(be32_to_cpu(stat) > NLM_FAILED);
p = xdr_reserve_space(xdr, 4);
*p = stat;
}
static int decode_nlm4_stat(struct xdr_stream *xdr, __be32 *stat)
{
__be32 *p;
p = xdr_inline_decode(xdr, 4);
if (unlikely(p == NULL))
goto out_overflow;
if (unlikely(ntohl(*p) > ntohl(nlm4_failed)))
goto out_bad_xdr;
*stat = *p;
return 0;
out_bad_xdr:
dprintk("%s: server returned invalid nlm4_stats value: %u\n",
__func__, be32_to_cpup(p));
return -EIO;
out_overflow:
print_overflow_msg(__func__, xdr);
return -EIO;
}
/*
* struct nlm4_holder {
* bool exclusive;
* int32 svid;
* netobj oh;
* uint64 l_offset;
* uint64 l_len;
* };
*/
static void encode_nlm4_holder(struct xdr_stream *xdr,
const struct nlm_res *result)
{
const struct nlm_lock *lock = &result->lock;
u64 l_offset, l_len;
__be32 *p;
encode_bool(xdr, lock->fl.fl_type == F_RDLCK);
encode_int32(xdr, lock->svid);
encode_netobj(xdr, lock->oh.data, lock->oh.len);
p = xdr_reserve_space(xdr, 4 + 4);
nlm4_compute_offsets(lock, &l_offset, &l_len);
p = xdr_encode_hyper(p, l_offset);
xdr_encode_hyper(p, l_len);
}
static int decode_nlm4_holder(struct xdr_stream *xdr, struct nlm_res *result)
{
struct nlm_lock *lock = &result->lock;
struct file_lock *fl = &lock->fl;
u64 l_offset, l_len;
u32 exclusive;
int error;
__be32 *p;
s32 end;
memset(lock, 0, sizeof(*lock));
locks_init_lock(fl);
p = xdr_inline_decode(xdr, 4 + 4);
if (unlikely(p == NULL))
goto out_overflow;
exclusive = be32_to_cpup(p++);
lock->svid = be32_to_cpup(p);
fl->fl_pid = (pid_t)lock->svid;
error = decode_netobj(xdr, &lock->oh);
if (unlikely(error))
goto out;
p = xdr_inline_decode(xdr, 8 + 8);
if (unlikely(p == NULL))
goto out_overflow;
fl->fl_flags = FL_POSIX;
fl->fl_type = exclusive != 0 ? F_WRLCK : F_RDLCK;
p = xdr_decode_hyper(p, &l_offset);
xdr_decode_hyper(p, &l_len);
end = l_offset + l_len - 1;
fl->fl_start = (loff_t)l_offset;
if (l_len == 0 || end < 0)
fl->fl_end = OFFSET_MAX;
else
fl->fl_end = (loff_t)end;
error = 0;
out:
return error;
out_overflow:
print_overflow_msg(__func__, xdr);
return -EIO;
}
/*
* string caller_name<LM_MAXSTRLEN>;
*/
static void encode_caller_name(struct xdr_stream *xdr, const char *name)
{
/* NB: client-side does not set lock->len */
u32 length = strlen(name);
__be32 *p;
p = xdr_reserve_space(xdr, 4 + length);
xdr_encode_opaque(p, name, length);
}
/*
* struct nlm4_lock {
* string caller_name<LM_MAXSTRLEN>;
* netobj fh;
* netobj oh;
* int32 svid;
* uint64 l_offset;
* uint64 l_len;
* };
*/
static void encode_nlm4_lock(struct xdr_stream *xdr,
const struct nlm_lock *lock)
{
u64 l_offset, l_len;
__be32 *p;
encode_caller_name(xdr, lock->caller);
encode_fh(xdr, &lock->fh);
encode_netobj(xdr, lock->oh.data, lock->oh.len);
p = xdr_reserve_space(xdr, 4 + 8 + 8);
*p++ = cpu_to_be32(lock->svid);
nlm4_compute_off
