2 * linux/fs/nfs/callback_xdr.c
4 * Copyright (C) 2004 Trond Myklebust
6 * NFSv4 callback encode/decode procedures
8 #include <linux/kernel.h>
9 #include <linux/sunrpc/svc.h>
10 #include <linux/nfs4.h>
11 #include <linux/nfs_fs.h>
15 #define CB_OP_TAGLEN_MAXSZ (512)
16 #define CB_OP_HDR_RES_MAXSZ (2 + CB_OP_TAGLEN_MAXSZ)
17 #define CB_OP_GETATTR_BITMAP_MAXSZ (4)
18 #define CB_OP_GETATTR_RES_MAXSZ (CB_OP_HDR_RES_MAXSZ + \
19 CB_OP_GETATTR_BITMAP_MAXSZ + \
21 #define CB_OP_RECALL_RES_MAXSZ (CB_OP_HDR_RES_MAXSZ)
23 #define NFSDBG_FACILITY NFSDBG_CALLBACK
25 typedef __be32 (*callback_process_op_t)(void *, void *);
26 typedef __be32 (*callback_decode_arg_t)(struct svc_rqst *, struct xdr_stream *, void *);
27 typedef __be32 (*callback_encode_res_t)(struct svc_rqst *, struct xdr_stream *, void *);
31 callback_process_op_t process_op;
32 callback_decode_arg_t decode_args;
33 callback_encode_res_t encode_res;
37 static struct callback_op callback_ops[];
39 static __be32 nfs4_callback_null(struct svc_rqst *rqstp, void *argp, void *resp)
41 return htonl(NFS4_OK);
44 static int nfs4_decode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
46 return xdr_argsize_check(rqstp, p);
49 static int nfs4_encode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
51 return xdr_ressize_check(rqstp, p);
54 static __be32 *read_buf(struct xdr_stream *xdr, int nbytes)
58 p = xdr_inline_decode(xdr, nbytes);
59 if (unlikely(p == NULL))
60 printk(KERN_WARNING "NFSv4 callback reply buffer overflowed!\n");
64 static __be32 decode_string(struct xdr_stream *xdr, unsigned int *len, const char **str)
69 if (unlikely(p == NULL))
70 return htonl(NFS4ERR_RESOURCE);
74 p = read_buf(xdr, *len);
75 if (unlikely(p == NULL))
76 return htonl(NFS4ERR_RESOURCE);
77 *str = (const char *)p;
84 static __be32 decode_fh(struct xdr_stream *xdr, struct nfs_fh *fh)
89 if (unlikely(p == NULL))
90 return htonl(NFS4ERR_RESOURCE);
92 if (fh->size > NFS4_FHSIZE)
93 return htonl(NFS4ERR_BADHANDLE);
94 p = read_buf(xdr, fh->size);
95 if (unlikely(p == NULL))
96 return htonl(NFS4ERR_RESOURCE);
97 memcpy(&fh->data[0], p, fh->size);
98 memset(&fh->data[fh->size], 0, sizeof(fh->data) - fh->size);
102 static __be32 decode_bitmap(struct xdr_stream *xdr, uint32_t *bitmap)
105 unsigned int attrlen;
107 p = read_buf(xdr, 4);
108 if (unlikely(p == NULL))
109 return htonl(NFS4ERR_RESOURCE);
111 p = read_buf(xdr, attrlen << 2);
112 if (unlikely(p == NULL))
113 return htonl(NFS4ERR_RESOURCE);
114 if (likely(attrlen > 0))
115 bitmap[0] = ntohl(*p++);
117 bitmap[1] = ntohl(*p);
121 static __be32 decode_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
125 p = read_buf(xdr, 16);
126 if (unlikely(p == NULL))
127 return htonl(NFS4ERR_RESOURCE);
128 memcpy(stateid->data, p, 16);
132 static __be32 decode_compound_hdr_arg(struct xdr_stream *xdr, struct cb_compound_hdr_arg *hdr)
135 unsigned int minor_version;
138 status = decode_string(xdr, &hdr->taglen, &hdr->tag);
139 if (unlikely(status != 0))
141 /* We do not like overly long tags! */
142 if (hdr->taglen > CB_OP_TAGLEN_MAXSZ - 12) {
143 printk("NFSv4 CALLBACK %s: client sent tag of length %u\n",
144 __FUNCTION__, hdr->taglen);
145 return htonl(NFS4ERR_RESOURCE);
147 p = read_buf(xdr, 12);
148 if (unlikely(p == NULL))
149 return htonl(NFS4ERR_RESOURCE);
150 minor_version = ntohl(*p++);
151 /* Check minor version is zero. */
152 if (minor_version != 0) {
153 printk(KERN_WARNING "%s: NFSv4 server callback with illegal minor version %u!\n",
154 __FUNCTION__, minor_version);
155 return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
157 hdr->callback_ident = ntohl(*p++);
158 hdr->nops = ntohl(*p);
162 static __be32 decode_op_hdr(struct xdr_stream *xdr, unsigned int *op)
165 p = read_buf(xdr, 4);
166 if (unlikely(p == NULL))
167 return htonl(NFS4ERR_RESOURCE);
172 static __be32 decode_getattr_args(struct svc_rqst *rqstp, struct xdr_stream *xdr, struct cb_getattrargs *args)
176 status = decode_fh(xdr, &args->fh);
177 if (unlikely(status != 0))
179 args->addr = svc_addr(rqstp);
180 status = decode_bitmap(xdr, args->bitmap);
182 dprintk("%s: exit with status = %d\n", __FUNCTION__, ntohl(status));
186 static __be32 decode_recall_args(struct svc_rqst *rqstp, struct xdr_stream *xdr, struct cb_recallargs *args)
191 args->addr = svc_addr(rqstp);
192 status = decode_stateid(xdr, &args->stateid);
193 if (unlikely(status != 0))
195 p = read_buf(xdr, 4);
196 if (unlikely(p == NULL)) {
197 status = htonl(NFS4ERR_RESOURCE);
200 args->truncate = ntohl(*p);
201 status = decode_fh(xdr, &args->fh);
203 dprintk("%s: exit with status = %d\n", __FUNCTION__, ntohl(status));
207 static __be32 encode_string(struct xdr_stream *xdr, unsigned int len, const char *str)
211 p = xdr_reserve_space(xdr, 4 + len);
212 if (unlikely(p == NULL))
213 return htonl(NFS4ERR_RESOURCE);
214 xdr_encode_opaque(p, str, len);
218 #define CB_SUPPORTED_ATTR0 (FATTR4_WORD0_CHANGE|FATTR4_WORD0_SIZE)
219 #define CB_SUPPORTED_ATTR1 (FATTR4_WORD1_TIME_METADATA|FATTR4_WORD1_TIME_MODIFY)
220 static __be32 encode_attr_bitmap(struct xdr_stream *xdr, const uint32_t *bitmap, __be32 **savep)
225 bm[0] = htonl(bitmap[0] & CB_SUPPORTED_ATTR0);
226 bm[1] = htonl(bitmap[1] & CB_SUPPORTED_ATTR1);
228 p = xdr_reserve_space(xdr, 16);
229 if (unlikely(p == NULL))
230 return htonl(NFS4ERR_RESOURCE);
234 } else if (bm[0] != 0) {
235 p = xdr_reserve_space(xdr, 12);
236 if (unlikely(p == NULL))
237 return htonl(NFS4ERR_RESOURCE);
241 p = xdr_reserve_space(xdr, 8);
242 if (unlikely(p == NULL))
243 return htonl(NFS4ERR_RESOURCE);
250 static __be32 encode_attr_change(struct xdr_stream *xdr, const uint32_t *bitmap, uint64_t change)
254 if (!(bitmap[0] & FATTR4_WORD0_CHANGE))
256 p = xdr_reserve_space(xdr, 8);
257 if (unlikely(p == 0))
258 return htonl(NFS4ERR_RESOURCE);
259 p = xdr_encode_hyper(p, change);
263 static __be32 encode_attr_size(struct xdr_stream *xdr, const uint32_t *bitmap, uint64_t size)
267 if (!(bitmap[0] & FATTR4_WORD0_SIZE))
269 p = xdr_reserve_space(xdr, 8);
270 if (unlikely(p == 0))
271 return htonl(NFS4ERR_RESOURCE);
272 p = xdr_encode_hyper(p, size);
276 static __be32 encode_attr_time(struct xdr_stream *xdr, const struct timespec *time)
280 p = xdr_reserve_space(xdr, 12);
281 if (unlikely(p == 0))
282 return htonl(NFS4ERR_RESOURCE);
283 p = xdr_encode_hyper(p, time->tv_sec);
284 *p = htonl(time->tv_nsec);
288 static __be32 encode_attr_ctime(struct xdr_stream *xdr, const uint32_t *bitmap, const struct timespec *time)
290 if (!(bitmap[1] & FATTR4_WORD1_TIME_METADATA))
292 return encode_attr_time(xdr,time);
295 static __be32 encode_attr_mtime(struct xdr_stream *xdr, const uint32_t *bitmap, const struct timespec *time)
297 if (!(bitmap[1] & FATTR4_WORD1_TIME_MODIFY))
299 return encode_attr_time(xdr,time);
302 static __be32 encode_compound_hdr_res(struct xdr_stream *xdr, struct cb_compound_hdr_res *hdr)
306 hdr->status = xdr_reserve_space(xdr, 4);
307 if (unlikely(hdr->status == NULL))
308 return htonl(NFS4ERR_RESOURCE);
309 status = encode_string(xdr, hdr->taglen, hdr->tag);
310 if (unlikely(status != 0))
312 hdr->nops = xdr_reserve_space(xdr, 4);
313 if (unlikely(hdr->nops == NULL))
314 return htonl(NFS4ERR_RESOURCE);
318 static __be32 encode_op_hdr(struct xdr_stream *xdr, uint32_t op, __be32 res)
322 p = xdr_reserve_space(xdr, 8);
323 if (unlikely(p == NULL))
324 return htonl(NFS4ERR_RESOURCE);
330 static __be32 encode_getattr_res(struct svc_rqst *rqstp, struct xdr_stream *xdr, const struct cb_getattrres *res)
332 __be32 *savep = NULL;
333 __be32 status = res->status;
335 if (unlikely(status != 0))
337 status = encode_attr_bitmap(xdr, res->bitmap, &savep);
338 if (unlikely(status != 0))
340 status = encode_attr_change(xdr, res->bitmap, res->change_attr);
341 if (unlikely(status != 0))
343 status = encode_attr_size(xdr, res->bitmap, res->size);
344 if (unlikely(status != 0))
346 status = encode_attr_ctime(xdr, res->bitmap, &res->ctime);
347 if (unlikely(status != 0))
349 status = encode_attr_mtime(xdr, res->bitmap, &res->mtime);
350 *savep = htonl((unsigned int)((char *)xdr->p - (char *)(savep+1)));
352 dprintk("%s: exit with status = %d\n", __FUNCTION__, ntohl(status));
356 static __be32 process_op(struct svc_rqst *rqstp,
357 struct xdr_stream *xdr_in, void *argp,
358 struct xdr_stream *xdr_out, void *resp)
360 struct callback_op *op = &callback_ops[0];
361 unsigned int op_nr = OP_CB_ILLEGAL;
366 dprintk("%s: start\n", __FUNCTION__);
367 status = decode_op_hdr(xdr_in, &op_nr);
368 if (likely(status == 0)) {
372 op = &callback_ops[op_nr];
375 op_nr = OP_CB_ILLEGAL;
376 op = &callback_ops[0];
377 status = htonl(NFS4ERR_OP_ILLEGAL);
381 maxlen = xdr_out->end - xdr_out->p;
382 if (maxlen > 0 && maxlen < PAGE_SIZE) {
383 if (likely(status == 0 && op->decode_args != NULL))
384 status = op->decode_args(rqstp, xdr_in, argp);
385 if (likely(status == 0 && op->process_op != NULL))
386 status = op->process_op(argp, resp);
388 status = htonl(NFS4ERR_RESOURCE);
390 res = encode_op_hdr(xdr_out, op_nr, status);
393 if (op->encode_res != NULL && status == 0)
394 status = op->encode_res(rqstp, xdr_out, resp);
395 dprintk("%s: done, status = %d\n", __FUNCTION__, ntohl(status));
400 * Decode, process and encode a COMPOUND
402 static __be32 nfs4_callback_compound(struct svc_rqst *rqstp, void *argp, void *resp)
404 struct cb_compound_hdr_arg hdr_arg;
405 struct cb_compound_hdr_res hdr_res;
406 struct xdr_stream xdr_in, xdr_out;
409 unsigned int nops = 1;
411 dprintk("%s: start\n", __FUNCTION__);
413 xdr_init_decode(&xdr_in, &rqstp->rq_arg, rqstp->rq_arg.head[0].iov_base);
415 p = (__be32*)((char *)rqstp->rq_res.head[0].iov_base + rqstp->rq_res.head[0].iov_len);
416 xdr_init_encode(&xdr_out, &rqstp->rq_res, p);
418 decode_compound_hdr_arg(&xdr_in, &hdr_arg);
419 hdr_res.taglen = hdr_arg.taglen;
420 hdr_res.tag = hdr_arg.tag;
422 encode_compound_hdr_res(&xdr_out, &hdr_res);
425 status = process_op(rqstp, &xdr_in, argp, &xdr_out, resp);
428 if (nops == hdr_arg.nops)
432 *hdr_res.status = status;
433 *hdr_res.nops = htonl(nops);
434 dprintk("%s: done, status = %u\n", __FUNCTION__, ntohl(status));
439 * Define NFS4 callback COMPOUND ops.
441 static struct callback_op callback_ops[] = {
443 .res_maxsize = CB_OP_HDR_RES_MAXSZ,
446 .process_op = (callback_process_op_t)nfs4_callback_getattr,
447 .decode_args = (callback_decode_arg_t)decode_getattr_args,
448 .encode_res = (callback_encode_res_t)encode_getattr_res,
449 .res_maxsize = CB_OP_GETATTR_RES_MAXSZ,
452 .process_op = (callback_process_op_t)nfs4_callback_recall,
453 .decode_args = (callback_decode_arg_t)decode_recall_args,
454 .res_maxsize = CB_OP_RECALL_RES_MAXSZ,
459 * Define NFS4 callback procedures
461 static struct svc_procedure nfs4_callback_procedures1[] = {
463 .pc_func = nfs4_callback_null,
464 .pc_decode = (kxdrproc_t)nfs4_decode_void,
465 .pc_encode = (kxdrproc_t)nfs4_encode_void,
469 .pc_func = nfs4_callback_compound,
470 .pc_encode = (kxdrproc_t)nfs4_encode_void,
473 .pc_xdrressize = NFS4_CALLBACK_BUFSIZE,
477 struct svc_version nfs4_callback_version1 = {
479 .vs_nproc = ARRAY_SIZE(nfs4_callback_procedures1),
480 .vs_proc = nfs4_callback_procedures1,
481 .vs_xdrsize = NFS4_CALLBACK_XDRSIZE,