fs/lockd/xdr4.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * linux/fs/lockd/xdr4.c
   4  *
   5  * XDR support for lockd and the lock client.
   6  *
   7  * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
   8  * Copyright (C) 1999, Trond Myklebust <trond.myklebust@fys.uio.no>
   9  */
  10
  11 #include <linux/types.h>
  12 #include <linux/sched.h>
  13 #include <linux/nfs.h>
  14
  15 #include <linux/sunrpc/xdr.h>
  16 #include <linux/sunrpc/clnt.h>
  17 #include <linux/sunrpc/svc.h>
  18 #include <linux/sunrpc/stats.h>
  19 #include <linux/lockd/lockd.h>
  20
  21 #define NLMDBG_FACILITY         NLMDBG_XDR
  22
  23 static inline loff_t
  24 s64_to_loff_t(__s64 offset)
  25 {
  26         return (loff_t)offset;
  27 }
  28
  29
  30 static inline s64
  31 loff_t_to_s64(loff_t offset)
  32 {
  33         s64 res;
  34         if (offset > NLM4_OFFSET_MAX)
  35                 res = NLM4_OFFSET_MAX;
  36         else if (offset < -NLM4_OFFSET_MAX)
  37                 res = -NLM4_OFFSET_MAX;
  38         else
  39                 res = offset;
  40         return res;
  41 }
  42
  43 /*
  44  * XDR functions for basic NLM types
  45  */
  46 static __be32 *
  47 nlm4_decode_cookie(__be32 *p, struct nlm_cookie *c)
  48 {
  49         unsigned int    len;
  50
  51         len = ntohl(*p++);
  52
  53         if(len==0)
  54         {
  55                 c->len=4;
  56                 memset(c->data, 0, 4);  /* hockeypux brain damage */
  57         }
  58         else if(len<=NLM_MAXCOOKIELEN)
  59         {
  60                 c->len=len;
  61                 memcpy(c->data, p, len);
  62                 p+=XDR_QUADLEN(len);
  63         }
  64         else
  65         {
  66                 dprintk("lockd: bad cookie size %d (only cookies under "
  67                         "%d bytes are supported.)\n",
  68                                 len, NLM_MAXCOOKIELEN);
  69                 return NULL;
  70         }
  71         return p;
  72 }
  73
  74 static __be32 *
  75 nlm4_encode_cookie(__be32 *p, struct nlm_cookie *c)
  76 {
  77         *p++ = htonl(c->len);
  78         memcpy(p, c->data, c->len);
  79         p+=XDR_QUADLEN(c->len);
  80         return p;
  81 }
  82
  83 static __be32 *
  84 nlm4_decode_fh(__be32 *p, struct nfs_fh *f)
  85 {
  86         memset(f->data, 0, sizeof(f->data));
  87         f->size = ntohl(*p++);
  88         if (f->size > NFS_MAXFHSIZE) {
  89                 dprintk("lockd: bad fhandle size %d (should be <=%d)\n",
  90                         f->size, NFS_MAXFHSIZE);
  91                 return NULL;
  92         }
  93         memcpy(f->data, p, f->size);
  94         return p + XDR_QUADLEN(f->size);
  95 }
  96
  97 /*
  98  * Encode and decode owner handle
  99  */
 100 static __be32 *
 101 nlm4_decode_oh(__be32 *p, struct xdr_netobj *oh)
 102 {
 103         return xdr_decode_netobj(p, oh);
 104 }
 105
 106 static __be32 *
 107 nlm4_decode_lock(__be32 *p, struct nlm_lock *lock)
 108 {
 109         struct file_lock        *fl = &lock->fl;
 110         __u64                   len, start;
 111         __s64                   end;
 112
 113         if (!(p = xdr_decode_string_inplace(p, &lock->caller,
 114                                             &lock->len, NLM_MAXSTRLEN))
 115          || !(p = nlm4_decode_fh(p, &lock->fh))
 116          || !(p = nlm4_decode_oh(p, &lock->oh)))
 117                 return NULL;
 118         lock->svid  = ntohl(*p++);
 119
 120         locks_init_lock(fl);
 121         fl->fl_flags = FL_POSIX;
 122         fl->fl_type  = F_RDLCK;         /* as good as anything else */
 123         p = xdr_decode_hyper(p, &start);
 124         p = xdr_decode_hyper(p, &len);
 125         end = start + len - 1;
 126
 127         fl->fl_start = s64_to_loff_t(start);
 128
 129         if (len == 0 || end < 0)
 130                 fl->fl_end = OFFSET_MAX;
 131         else
 132                 fl->fl_end = s64_to_loff_t(end);
 133         return p;
 134 }
 135
 136 /*
 137  * Encode result of a TEST/TEST_MSG call
 138  */
 139 static __be32 *
 140 nlm4_encode_testres(__be32 *p, struct nlm_res *resp)
 141 {
 142         s64             start, len;
 143
 144         dprintk("xdr: before encode_testres (p %p resp %p)\n", p, resp);
 145         if (!(p = nlm4_encode_cookie(p, &resp->cookie)))
 146                 return NULL;
 147         *p++ = resp->status;
 148
 149         if (resp->status == nlm_lck_denied) {
 150                 struct file_lock        *fl = &resp->lock.fl;
 151
 152                 *p++ = (fl->fl_type == F_RDLCK)? xdr_zero : xdr_one;
 153                 *p++ = htonl(resp->lock.svid);
 154
 155                 /* Encode owner handle. */
 156                 if (!(p = xdr_encode_netobj(p, &resp->lock.oh)))
 157                         return NULL;
 158
 159                 start = loff_t_to_s64(fl->fl_start);
 160                 if (fl->fl_end == OFFSET_MAX)
 161                         len = 0;
 162                 else
 163                         len = loff_t_to_s64(fl->fl_end - fl->fl_start + 1);
 164
 165                 p = xdr_encode_hyper(p, start);
 166                 p = xdr_encode_hyper(p, len);
 167                 dprintk("xdr: encode_testres (status %u pid %d type %d start %Ld end %Ld)\n",
 168                         resp->status, (int)resp->lock.svid, fl->fl_type,
 169                         (long long)fl->fl_start,  (long long)fl->fl_end);
 170         }
 171
 172         dprintk("xdr: after encode_testres (p %p resp %p)\n", p, resp);
 173         return p;
 174 }
 175
 176
 177 /*
 178  * First, the server side XDR functions
 179  */
 180 int
 181 nlm4svc_decode_testargs(struct svc_rqst *rqstp, __be32 *p)
 182 {
 183         struct nlm_args *argp = rqstp->rq_argp;
 184         u32     exclusive;
 185
 186         if (!(p = nlm4_decode_cookie(p, &argp->cookie)))
 187                 return 0;
 188
 189         exclusive = ntohl(*p++);
 190         if (!(p = nlm4_decode_lock(p, &argp->lock)))
 191                 return 0;
 192         if (exclusive)
 193                 argp->lock.fl.fl_type = F_WRLCK;
 194
 195         return xdr_argsize_check(rqstp, p);
 196 }
 197
 198 int
 199 nlm4svc_encode_testres(struct svc_rqst *rqstp, __be32 *p)
 200 {
 201         struct nlm_res *resp = rqstp->rq_resp;
 202
 203         if (!(p = nlm4_encode_testres(p, resp)))
 204                 return 0;
 205         return xdr_ressize_check(rqstp, p);
 206 }
 207
 208 int
 209 nlm4svc_decode_lockargs(struct svc_rqst *rqstp, __be32 *p)
 210 {
 211         struct nlm_args *argp = rqstp->rq_argp;
 212         u32     exclusive;
 213
 214         if (!(p = nlm4_decode_cookie(p, &argp->cookie)))
 215                 return 0;
 216         argp->block  = ntohl(*p++);
 217         exclusive    = ntohl(*p++);
 218         if (!(p = nlm4_decode_lock(p, &argp->lock)))
 219                 return 0;
 220         if (exclusive)
 221                 argp->lock.fl.fl_type = F_WRLCK;
 222         argp->reclaim = ntohl(*p++);
 223         argp->state   = ntohl(*p++);
 224         argp->monitor = 1;              /* monitor client by default */
 225
 226         return xdr_argsize_check(rqstp, p);
 227 }
 228
 229 int
 230 nlm4svc_decode_cancargs(struct svc_rqst *rqstp, __be32 *p)
 231 {
 232         struct nlm_args *argp = rqstp->rq_argp;
 233         u32     exclusive;
 234
 235         if (!(p = nlm4_decode_cookie(p, &argp->cookie)))
 236                 return 0;
 237         argp->block = ntohl(*p++);
 238         exclusive = ntohl(*p++);
 239         if (!(p = nlm4_decode_lock(p, &argp->lock)))
 240                 return 0;
 241         if (exclusive)
 242                 argp->lock.fl.fl_type = F_WRLCK;
 243         return xdr_argsize_check(rqstp, p);
 244 }
 245
 246 int
 247 nlm4svc_decode_unlockargs(struct svc_rqst *rqstp, __be32 *p)
 248 {
 249         struct nlm_args *argp = rqstp->rq_argp;
 250
 251         if (!(p = nlm4_decode_cookie(p, &argp->cookie))
 252          || !(p = nlm4_decode_lock(p, &argp->lock)))
 253                 return 0;
 254         argp->lock.fl.fl_type = F_UNLCK;
 255         return xdr_argsize_check(rqstp, p);
 256 }
 257
 258 int
 259 nlm4svc_decode_shareargs(struct svc_rqst *rqstp, __be32 *p)
 260 {
 261         struct nlm_args *argp = rqstp->rq_argp;
 262         struct nlm_lock *lock = &argp->lock;
 263
 264         memset(lock, 0, sizeof(*lock));
 265         locks_init_lock(&lock->fl);
 266         lock->svid = ~(u32) 0;
 267
 268         if (!(p = nlm4_decode_cookie(p, &argp->cookie))
 269          || !(p = xdr_decode_string_inplace(p, &lock->caller,
 270                                             &lock->len, NLM_MAXSTRLEN))
 271          || !(p = nlm4_decode_fh(p, &lock->fh))
 272          || !(p = nlm4_decode_oh(p, &lock->oh)))
 273                 return 0;
 274         argp->fsm_mode = ntohl(*p++);
 275         argp->fsm_access = ntohl(*p++);
 276         return xdr_argsize_check(rqstp, p);
 277 }
 278
 279 int
 280 nlm4svc_encode_shareres(struct svc_rqst *rqstp, __be32 *p)
 281 {
 282         struct nlm_res *resp = rqstp->rq_resp;
 283
 284         if (!(p = nlm4_encode_cookie(p, &resp->cookie)))
 285                 return 0;
 286         *p++ = resp->status;
 287         *p++ = xdr_zero;                /* sequence argument */
 288         return xdr_ressize_check(rqstp, p);
 289 }
 290
 291 int
 292 nlm4svc_encode_res(struct svc_rqst *rqstp, __be32 *p)
 293 {
 294         struct nlm_res *resp = rqstp->rq_resp;
 295
 296         if (!(p = nlm4_encode_cookie(p, &resp->cookie)))
 297                 return 0;
 298         *p++ = resp->status;
 299         return xdr_ressize_check(rqstp, p);
 300 }
 301
 302 int
 303 nlm4svc_decode_notify(struct svc_rqst *rqstp, __be32 *p)
 304 {
 305         struct nlm_args *argp = rqstp->rq_argp;
 306         struct nlm_lock *lock = &argp->lock;
 307
 308         if (!(p = xdr_decode_string_inplace(p, &lock->caller,
 309                                             &lock->len, NLM_MAXSTRLEN)))
 310                 return 0;
 311         argp->state = ntohl(*p++);
 312         return xdr_argsize_check(rqstp, p);
 313 }
 314
 315 int
 316 nlm4svc_decode_reboot(struct svc_rqst *rqstp, __be32 *p)
 317 {
 318         struct nlm_reboot *argp = rqstp->rq_argp;
 319
 320         if (!(p = xdr_decode_string_inplace(p, &argp->mon, &argp->len, SM_MAXSTRLEN)))
 321                 return 0;
 322         argp->state = ntohl(*p++);
 323         memcpy(&argp->priv.data, p, sizeof(argp->priv.data));
 324         p += XDR_QUADLEN(SM_PRIV_SIZE);
 325         return xdr_argsize_check(rqstp, p);
 326 }
 327
 328 int
 329 nlm4svc_decode_res(struct svc_rqst *rqstp, __be32 *p)
 330 {
 331         struct nlm_res *resp = rqstp->rq_argp;
 332
 333         if (!(p = nlm4_decode_cookie(p, &resp->cookie)))
 334                 return 0;
 335         resp->status = *p++;
 336         return xdr_argsize_check(rqstp, p);
 337 }
 338
 339 int
 340 nlm4svc_decode_void(struct svc_rqst *rqstp, __be32 *p)
 341 {
 342         return xdr_argsize_check(rqstp, p);
 343 }
 344
 345 int
 346 nlm4svc_encode_void(struct svc_rqst *rqstp, __be32 *p)
 347 {
 348         return xdr_ressize_check(rqstp, p);
 349 }