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)
137 status = decode_string(xdr, &hdr->taglen, &hdr->tag);
138 if (unlikely(status != 0))
140 /* We do not like overly long tags! */
141 if (hdr->taglen > CB_OP_TAGLEN_MAXSZ - 12) {
142 printk("NFSv4 CALLBACK %s: client sent tag of length %u\n",
143 __func__, hdr->taglen);
144 return htonl(NFS4ERR_RESOURCE);
146 p = read_buf(xdr, 12);
147 if (unlikely(p == NULL))
148 return htonl(NFS4ERR_RESOURCE);
149 hdr->minorversion = ntohl(*p++);
150 /* Check minor version is zero. */
151 if (hdr->minorversion != 0) {
152 printk(KERN_WARNING "%s: NFSv4 server callback with "
153 "illegal minor version %u!\n",
154 __func__, hdr->minorversion);
155 return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
157 hdr->callback_ident = ntohl(*p++);
158 hdr->nops = ntohl(*p);
159 dprintk("%s: minorversion %d nops %d\n", __func__,
160 hdr->minorversion, hdr->nops);
164 static __be32 decode_op_hdr(struct xdr_stream *xdr, unsigned int *op)
167 p = read_buf(xdr, 4);
168 if (unlikely(p == NULL))
169 return htonl(NFS4ERR_RESOURCE);
174 static __be32 decode_getattr_args(struct svc_rqst *rqstp, struct xdr_stream *xdr, struct cb_getattrargs *args)
178 status = decode_fh(xdr, &args->fh);
179 if (unlikely(status != 0))
181 args->addr = svc_addr(rqstp);
182 status = decode_bitmap(xdr, args->bitmap);
184 dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
188 static __be32 decode_recall_args(struct svc_rqst *rqstp, struct xdr_stream *xdr, struct cb_recallargs *args)
193 args->addr = svc_addr(rqstp);
194 status = decode_stateid(xdr, &args->stateid);
195 if (unlikely(status != 0))
197 p = read_buf(xdr, 4);
198 if (unlikely(p == NULL)) {
199 status = htonl(NFS4ERR_RESOURCE);
202 args->truncate = ntohl(*p);
203 status = decode_fh(xdr, &args->fh);
205 dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
209 static __be32 encode_string(struct xdr_stream *xdr, unsigned int len, const char *str)
213 p = xdr_reserve_space(xdr, 4 + len);
214 if (unlikely(p == NULL))
215 return htonl(NFS4ERR_RESOURCE);
216 xdr_encode_opaque(p, str, len);
220 #define CB_SUPPORTED_ATTR0 (FATTR4_WORD0_CHANGE|FATTR4_WORD0_SIZE)
221 #define CB_SUPPORTED_ATTR1 (FATTR4_WORD1_TIME_METADATA|FATTR4_WORD1_TIME_MODIFY)
222 static __be32 encode_attr_bitmap(struct xdr_stream *xdr, const uint32_t *bitmap, __be32 **savep)
227 bm[0] = htonl(bitmap[0] & CB_SUPPORTED_ATTR0);
228 bm[1] = htonl(bitmap[1] & CB_SUPPORTED_ATTR1);
230 p = xdr_reserve_space(xdr, 16);
231 if (unlikely(p == NULL))
232 return htonl(NFS4ERR_RESOURCE);
236 } else if (bm[0] != 0) {
237 p = xdr_reserve_space(xdr, 12);
238 if (unlikely(p == NULL))
239 return htonl(NFS4ERR_RESOURCE);
243 p = xdr_reserve_space(xdr, 8);
244 if (unlikely(p == NULL))
245 return htonl(NFS4ERR_RESOURCE);
252 static __be32 encode_attr_change(struct xdr_stream *xdr, const uint32_t *bitmap, uint64_t change)
256 if (!(bitmap[0] & FATTR4_WORD0_CHANGE))
258 p = xdr_reserve_space(xdr, 8);
260 return htonl(NFS4ERR_RESOURCE);
261 p = xdr_encode_hyper(p, change);
265 static __be32 encode_attr_size(struct xdr_stream *xdr, const uint32_t *bitmap, uint64_t size)
269 if (!(bitmap[0] & FATTR4_WORD0_SIZE))
271 p = xdr_reserve_space(xdr, 8);
273 return htonl(NFS4ERR_RESOURCE);
274 p = xdr_encode_hyper(p, size);
278 static __be32 encode_attr_time(struct xdr_stream *xdr, const struct timespec *time)
282 p = xdr_reserve_space(xdr, 12);
284 return htonl(NFS4ERR_RESOURCE);
285 p = xdr_encode_hyper(p, time->tv_sec);
286 *p = htonl(time->tv_nsec);
290 static __be32 encode_attr_ctime(struct xdr_stream *xdr, const uint32_t *bitmap, const struct timespec *time)
292 if (!(bitmap[1] & FATTR4_WORD1_TIME_METADATA))
294 return encode_attr_time(xdr,time);
297 static __be32 encode_attr_mtime(struct xdr_stream *xdr, const uint32_t *bitmap, const struct timespec *time)
299 if (!(bitmap[1] & FATTR4_WORD1_TIME_MODIFY))
301 return encode_attr_time(xdr,time);
304 static __be32 encode_compound_hdr_res(struct xdr_stream *xdr, struct cb_compound_hdr_res *hdr)
308 hdr->status = xdr_reserve_space(xdr, 4);
309 if (unlikely(hdr->status == NULL))
310 return htonl(NFS4ERR_RESOURCE);
311 status = encode_string(xdr, hdr->taglen, hdr->tag);
312 if (unlikely(status != 0))
314 hdr->nops = xdr_reserve_space(xdr, 4);
315 if (unlikely(hdr->nops == NULL))
316 return htonl(NFS4ERR_RESOURCE);
320 static __be32 encode_op_hdr(struct xdr_stream *xdr, uint32_t op, __be32 res)
324 p = xdr_reserve_space(xdr, 8);
325 if (unlikely(p == NULL))
326 return htonl(NFS4ERR_RESOURCE);
332 static __be32 encode_getattr_res(struct svc_rqst *rqstp, struct xdr_stream *xdr, const struct cb_getattrres *res)
334 __be32 *savep = NULL;
335 __be32 status = res->status;
337 if (unlikely(status != 0))
339 status = encode_attr_bitmap(xdr, res->bitmap, &savep);
340 if (unlikely(status != 0))
342 status = encode_attr_change(xdr, res->bitmap, res->change_attr);
343 if (unlikely(status != 0))
345 status = encode_attr_size(xdr, res->bitmap, res->size);
346 if (unlikely(status != 0))
348 status = encode_attr_ctime(xdr, res->bitmap, &res->ctime);
349 if (unlikely(status != 0))
351 status = encode_attr_mtime(xdr, res->bitmap, &res->mtime);
352 *savep = htonl((unsigned int)((char *)xdr->p - (char *)(savep+1)));
354 dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
358 static __be32 process_op(struct svc_rqst *rqstp,
359 struct xdr_stream *xdr_in, void *argp,
360 struct xdr_stream *xdr_out, void *resp)
362 struct callback_op *op = &callback_ops[0];
363 unsigned int op_nr = OP_CB_ILLEGAL;
368 dprintk("%s: start\n", __func__);
369 status = decode_op_hdr(xdr_in, &op_nr);
370 if (likely(status == 0)) {
374 op = &callback_ops[op_nr];
377 op_nr = OP_CB_ILLEGAL;
378 op = &callback_ops[0];
379 status = htonl(NFS4ERR_OP_ILLEGAL);
383 maxlen = xdr_out->end - xdr_out->p;
384 if (maxlen > 0 && maxlen < PAGE_SIZE) {
385 if (likely(status == 0 && op->decode_args != NULL))
386 status = op->decode_args(rqstp, xdr_in, argp);
387 if (likely(status == 0 && op->process_op != NULL))
388 status = op->process_op(argp, resp);
390 status = htonl(NFS4ERR_RESOURCE);
392 res = encode_op_hdr(xdr_out, op_nr, status);
395 if (op->encode_res != NULL && status == 0)
396 status = op->encode_res(rqstp, xdr_out, resp);
397 dprintk("%s: done, status = %d\n", __func__, ntohl(status));
402 * Decode, process and encode a COMPOUND
404 static __be32 nfs4_callback_compound(struct svc_rqst *rqstp, void *argp, void *resp)
406 struct cb_compound_hdr_arg hdr_arg = { 0 };
407 struct cb_compound_hdr_res hdr_res = { NULL };
408 struct xdr_stream xdr_in, xdr_out;
411 unsigned int nops = 0;
413 dprintk("%s: start\n", __func__);
415 xdr_init_decode(&xdr_in, &rqstp->rq_arg, rqstp->rq_arg.head[0].iov_base);
417 p = (__be32*)((char *)rqstp->rq_res.head[0].iov_base + rqstp->rq_res.head[0].iov_len);
418 xdr_init_encode(&xdr_out, &rqstp->rq_res, p);
420 status = decode_compound_hdr_arg(&xdr_in, &hdr_arg);
421 if (status == __constant_htonl(NFS4ERR_RESOURCE))
422 return rpc_garbage_args;
424 hdr_res.taglen = hdr_arg.taglen;
425 hdr_res.tag = hdr_arg.tag;
426 if (encode_compound_hdr_res(&xdr_out, &hdr_res) != 0)
427 return rpc_system_err;
429 while (status == 0 && nops != hdr_arg.nops) {
430 status = process_op(rqstp, &xdr_in, argp, &xdr_out, resp);
434 *hdr_res.status = status;
435 *hdr_res.nops = htonl(nops);
436 dprintk("%s: done, status = %u\n", __func__, ntohl(status));
441 * Define NFS4 callback COMPOUND ops.
443 static struct callback_op callback_ops[] = {
445 .res_maxsize = CB_OP_HDR_RES_MAXSZ,
448 .process_op = (callback_process_op_t)nfs4_callback_getattr,
449 .decode_args = (callback_decode_arg_t)decode_getattr_args,
450 .encode_res = (callback_encode_res_t)encode_getattr_res,
451 .res_maxsize = CB_OP_GETATTR_RES_MAXSZ,
454 .process_op = (callback_process_op_t)nfs4_callback_recall,
455 .decode_args = (callback_decode_arg_t)decode_recall_args,
456 .res_maxsize = CB_OP_RECALL_RES_MAXSZ,
461 * Define NFS4 callback procedures
463 static struct svc_procedure nfs4_callback_procedures1[] = {
465 .pc_func = nfs4_callback_null,
466 .pc_decode = (kxdrproc_t)nfs4_decode_void,
467 .pc_encode = (kxdrproc_t)nfs4_encode_void,
471 .pc_func = nfs4_callback_compound,
472 .pc_encode = (kxdrproc_t)nfs4_encode_void,
475 .pc_xdrressize = NFS4_CALLBACK_BUFSIZE,
479 struct svc_version nfs4_callback_version1 = {
481 .vs_nproc = ARRAY_SIZE(nfs4_callback_procedures1),
482 .vs_proc = nfs4_callback_procedures1,
483 .vs_xdrsize = NFS4_CALLBACK_XDRSIZE,