fs/lockd/xdr.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * linux/fs/lockd/xdr.c
   4  *
   5  * XDR support for lockd and the lock client.
   6  *
   7  * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
   8  */
   9
  10 #include <linux/types.h>
  11 #include <linux/sched.h>
  12 #include <linux/nfs.h>
  13
  14 #include <linux/sunrpc/xdr.h>
  15 #include <linux/sunrpc/clnt.h>
  16 #include <linux/sunrpc/svc.h>
  17 #include <linux/sunrpc/stats.h>
  18 #include <linux/lockd/lockd.h>
  19
  20 #include <uapi/linux/nfs2.h>
  21
  22 #define NLMDBG_FACILITY         NLMDBG_XDR
  23
  24
  25 static inline loff_t
  26 s32_to_loff_t(__s32 offset)
  27 {
  28         return (loff_t)offset;
  29 }
  30
  31 static inline __s32
  32 loff_t_to_s32(loff_t offset)
  33 {
  34         __s32 res;
  35         if (offset >= NLM_OFFSET_MAX)
  36                 res = NLM_OFFSET_MAX;
  37         else if (offset <= -NLM_OFFSET_MAX)
  38                 res = -NLM_OFFSET_MAX;
  39         else
  40                 res = offset;
  41         return res;
  42 }
  43
  44 /*
  45  * XDR functions for basic NLM types
  46  */
  47 static __be32 *nlm_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 inline __be32 *
  75 nlm_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 nlm_decode_fh(__be32 *p, struct nfs_fh *f)
  85 {
  86         unsigned int    len;
  87
  88         if ((len = ntohl(*p++)) != NFS2_FHSIZE) {
  89                 dprintk("lockd: bad fhandle size %d (should be %d)\n",
  90                         len, NFS2_FHSIZE);
  91                 return NULL;
  92         }
  93         f->size = NFS2_FHSIZE;
  94         memset(f->data, 0, sizeof(f->data));
  95         memcpy(f->data, p, NFS2_FHSIZE);
  96         return p + XDR_QUADLEN(NFS2_FHSIZE);
  97 }
  98
  99 /*
 100  * Encode and decode owner handle
 101  */
 102 static inline __be32 *
 103 nlm_decode_oh(__be32 *p, struct xdr_netobj *oh)
 104 {
 105         return xdr_decode_netobj(p, oh);
 106 }
 107
 108 static inline __be32 *
 109 nlm_encode_oh(__be32 *p, struct xdr_netobj *oh)
 110 {
 111         return xdr_encode_netobj(p, oh);
 112 }
 113
 114 static __be32 *
 115 nlm_decode_lock(__be32 *p, struct nlm_lock *lock)
 116 {
 117         struct file_lock        *fl = &lock->fl;
 118         s32                     start, len, end;
 119
 120         if (!(p = xdr_decode_string_inplace(p, &lock->caller,
 121                                             &lock->len,
 122                                             NLM_MAXSTRLEN))
 123          || !(p = nlm_decode_fh(p, &lock->fh))
 124          || !(p = nlm_decode_oh(p, &lock->oh)))
 125                 return NULL;
 126         lock->svid  = ntohl(*p++);
 127
 128         locks_init_lock(fl);
 129         fl->fl_owner = current->files;
 130         fl->fl_pid   = (pid_t)lock->svid;
 131         fl->fl_flags = FL_POSIX;
 132         fl->fl_type  = F_RDLCK;         /* as good as anything else */
 133         start = ntohl(*p++);
 134         len = ntohl(*p++);
 135         end = start + len - 1;
 136
 137         fl->fl_start = s32_to_loff_t(start);
 138
 139         if (len == 0 || end < 0)
 140                 fl->fl_end = OFFSET_MAX;
 141         else
 142                 fl->fl_end = s32_to_loff_t(end);
 143         return p;
 144 }
 145
 146 /*
 147  * Encode result of a TEST/TEST_MSG call
 148  */
 149 static __be32 *
 150 nlm_encode_testres(__be32 *p, struct nlm_res *resp)
 151 {
 152         s32             start, len;
 153
 154         if (!(p = nlm_encode_cookie(p, &resp->cookie)))
 155                 return NULL;
 156         *p++ = resp->status;
 157
 158         if (resp->status == nlm_lck_denied) {
 159                 struct file_lock        *fl = &resp->lock.fl;
 160
 161                 *p++ = (fl->fl_type == F_RDLCK)? xdr_zero : xdr_one;
 162                 *p++ = htonl(resp->lock.svid);
 163
 164                 /* Encode owner handle. */
 165                 if (!(p = xdr_encode_netobj(p, &resp->lock.oh)))
 166                         return NULL;
 167
 168                 start = loff_t_to_s32(fl->fl_start);
 169                 if (fl->fl_end == OFFSET_MAX)
 170                         len = 0;
 171                 else
 172                         len = loff_t_to_s32(fl->fl_end - fl->fl_start + 1);
 173
 174                 *p++ = htonl(start);
 175                 *p++ = htonl(len);
 176         }
 177
 178         return p;
 179 }
 180
 181
 182 /*
 183  * First, the server side XDR functions
 184  */
 185 int
 186 nlmsvc_decode_testargs(struct svc_rqst *rqstp, __be32 *p)
 187 {
 188         struct nlm_args *argp = rqstp->rq_argp;
 189         u32     exclusive;
 190
 191         if (!(p = nlm_decode_cookie(p, &argp->cookie)))
 192                 return 0;
 193
 194         exclusive = ntohl(*p++);
 195         if (!(p = nlm_decode_lock(p, &argp->lock)))
 196                 return 0;
 197         if (exclusive)
 198                 argp->lock.fl.fl_type = F_WRLCK;
 199
 200         return xdr_argsize_check(rqstp, p);
 201 }
 202
 203 int
 204 nlmsvc_encode_testres(struct svc_rqst *rqstp, __be32 *p)
 205 {
 206         struct nlm_res *resp = rqstp->rq_resp;
 207
 208         if (!(p = nlm_encode_testres(p, resp)))
 209                 return 0;
 210         return xdr_ressize_check(rqstp, p);
 211 }
 212
 213 int
 214 nlmsvc_decode_lockargs(struct svc_rqst *rqstp, __be32 *p)
 215 {
 216         struct nlm_args *argp = rqstp->rq_argp;
 217         u32     exclusive;
 218
 219         if (!(p = nlm_decode_cookie(p, &argp->cookie)))
 220                 return 0;
 221         argp->block  = ntohl(*p++);
 222         exclusive    = ntohl(*p++);
 223         if (!(p = nlm_decode_lock(p, &argp->lock)))
 224                 return 0;
 225         if (exclusive)
 226                 argp->lock.fl.fl_type = F_WRLCK;
 227         argp->reclaim = ntohl(*p++);
 228         argp->state   = ntohl(*p++);
 229         argp->monitor = 1;              /* monitor client by default */
 230
 231         return xdr_argsize_check(rqstp, p);
 232 }
 233
 234 int
 235 nlmsvc_decode_cancargs(struct svc_rqst *rqstp, __be32 *p)
 236 {
 237         struct nlm_args *argp = rqstp->rq_argp;
 238         u32     exclusive;
 239
 240         if (!(p = nlm_decode_cookie(p, &argp->cookie)))
 241                 return 0;
 242         argp->block = ntohl(*p++);
 243         exclusive = ntohl(*p++);
 244         if (!(p = nlm_decode_lock(p, &argp->lock)))
 245                 return 0;
 246         if (exclusive)
 247                 argp->lock.fl.fl_type = F_WRLCK;
 248         return xdr_argsize_check(rqstp, p);
 249 }
 250
 251 int
 252 nlmsvc_decode_unlockargs(struct svc_rqst *rqstp, __be32 *p)
 253 {
 254         struct nlm_args *argp = rqstp->rq_argp;
 255
 256         if (!(p = nlm_decode_cookie(p, &argp->cookie))
 257          || !(p = nlm_decode_lock(p, &argp->lock)))
 258                 return 0;
 259         argp->lock.fl.fl_type = F_UNLCK;
 260         return xdr_argsize_check(rqstp, p);
 261 }
 262
 263 int
 264 nlmsvc_decode_shareargs(struct svc_rqst *rqstp, __be32 *p)
 265 {
 266         struct nlm_args *argp = rqstp->rq_argp;
 267         struct nlm_lock *lock = &argp->lock;
 268
 269         memset(lock, 0, sizeof(*lock));
 270         locks_init_lock(&lock->fl);
 271         lock->svid = ~(u32) 0;
 272         lock->fl.fl_pid = (pid_t)lock->svid;
 273
 274         if (!(p = nlm_decode_cookie(p, &argp->cookie))
 275          || !(p = xdr_decode_string_inplace(p, &lock->caller,
 276                                             &lock->len, NLM_MAXSTRLEN))
 277          || !(p = nlm_decode_fh(p, &lock->fh))
 278          || !(p = nlm_decode_oh(p, &lock->oh)))
 279                 return 0;
 280         argp->fsm_mode = ntohl(*p++);
 281         argp->fsm_access = ntohl(*p++);
 282         return xdr_argsize_check(rqstp, p);
 283 }
 284
 285 int
 286 nlmsvc_encode_shareres(struct svc_rqst *rqstp, __be32 *p)
 287 {
 288         struct nlm_res *resp = rqstp->rq_resp;
 289
 290         if (!(p = nlm_encode_cookie(p, &resp->cookie)))
 291                 return 0;
 292         *p++ = resp->status;
 293         *p++ = xdr_zero;                /* sequence argument */
 294         return xdr_ressize_check(rqstp, p);
 295 }
 296
 297 int
 298 nlmsvc_encode_res(struct svc_rqst *rqstp, __be32 *p)
 299 {
 300         struct nlm_res *resp = rqstp->rq_resp;
 301
 302         if (!(p = nlm_encode_cookie(p, &resp->cookie)))
 303                 return 0;
 304         *p++ = resp->status;
 305         return xdr_ressize_check(rqstp, p);
 306 }
 307
 308 int
 309 nlmsvc_decode_notify(struct svc_rqst *rqstp, __be32 *p)
 310 {
 311         struct nlm_args *argp = rqstp->rq_argp;
 312         struct nlm_lock *lock = &argp->lock;
 313
 314         if (!(p = xdr_decode_string_inplace(p, &lock->caller,
 315                                             &lock->len, NLM_MAXSTRLEN)))
 316                 return 0;
 317         argp->state = ntohl(*p++);
 318         return xdr_argsize_check(rqstp, p);
 319 }
 320
 321 int
 322 nlmsvc_decode_reboot(struct svc_rqst *rqstp, __be32 *p)
 323 {
 324         struct nlm_reboot *argp = rqstp->rq_argp;
 325
 326         if (!(p = xdr_decode_string_inplace(p, &argp->mon, &argp->len, SM_MAXSTRLEN)))
 327                 return 0;
 328         argp->state = ntohl(*p++);
 329         memcpy(&argp->priv.data, p, sizeof(argp->priv.data));
 330         p += XDR_QUADLEN(SM_PRIV_SIZE);
 331         return xdr_argsize_check(rqstp, p);
 332 }
 333
 334 int
 335 nlmsvc_decode_res(struct svc_rqst *rqstp, __be32 *p)
 336 {
 337         struct nlm_res *resp = rqstp->rq_argp;
 338
 339         if (!(p = nlm_decode_cookie(p, &resp->cookie)))
 340                 return 0;
 341         resp->status = *p++;
 342         return xdr_argsize_check(rqstp, p);
 343 }
 344
 345 int
 346 nlmsvc_decode_void(struct svc_rqst *rqstp, __be32 *p)
 347 {
 348         return xdr_argsize_check(rqstp, p);
 349 }
 350
 351 int
 352 nlmsvc_encode_void(struct svc_rqst *rqstp, __be32 *p)
 353 {
 354         return xdr_ressize_check(rqstp, p);
 355 }