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_owner = current->files;
 122         fl->fl_pid   = (pid_t)lock->svid;
 123         fl->fl_flags = FL_POSIX;
 124         fl->fl_type  = F_RDLCK;         /* as good as anything else */
 125         p = xdr_decode_hyper(p, &start);
 126         p = xdr_decode_hyper(p, &len);
 127         end = start + len - 1;
 128
 129         fl->fl_start = s64_to_loff_t(start);
 130
 131         if (len == 0 || end < 0)
 132                 fl->fl_end = OFFSET_MAX;
 133         else
 134                 fl->fl_end = s64_to_loff_t(end);
 135         return p;
 136 }
 137
 138 /*
 139  * Encode result of a TEST/TEST_MSG call
 140  */
 141 static __be32 *
 142 nlm4_encode_testres(__be32 *p, struct nlm_res *resp)
 143 {
 144         s64             start, len;
 145
 146         dprintk("xdr: before encode_testres (p %p resp %p)\n", p, resp);
 147         if (!(p = nlm4_encode_cookie(p, &resp->cookie)))
 148                 return NULL;
 149         *p++ = resp->status;
 150
 151         if (resp->status == nlm_lck_denied) {
 152                 struct file_lock        *fl = &resp->lock.fl;
 153
 154                 *p++ = (fl->fl_type == F_RDLCK)? xdr_zero : xdr_one;
 155                 *p++ = htonl(resp->lock.svid);
 156
 157                 /* Encode owner handle. */
 158                 if (!(p = xdr_encode_netobj(p, &resp->lock.oh)))
 159                         return NULL;
 160
 161                 start = loff_t_to_s64(fl->fl_start);
 162                 if (fl->fl_end == OFFSET_MAX)
 163                         len = 0;
 164                 else
 165                         len = loff_t_to_s64(fl->fl_end - fl->fl_start + 1);
 166
 167                 p = xdr_encode_hyper(p, start);
 168                 p = xdr_encode_hyper(p, len);
 169                 dprintk("xdr: encode_testres (status %u pid %d type %d start %Ld end %Ld)\n",
 170                         resp->status, (int)resp->lock.svid, fl->fl_type,
 171                         (long long)fl->fl_start,  (long long)fl->fl_end);
 172         }
 173
 174         dprintk("xdr: after encode_testres (p %p resp %p)\n", p, resp);
 175         return p;
 176 }
 177
 178
 179 /*
 180  * First, the server side XDR functions
 181  */
 182 int
 183 nlm4svc_decode_testargs(struct svc_rqst *rqstp, __be32 *p)
 184 {
 185         struct nlm_args *argp = rqstp->rq_argp;
 186         u32     exclusive;
 187
 188         if (!(p = nlm4_decode_cookie(p, &argp->cookie)))
 189                 return 0;
 190
 191         exclusive = ntohl(*p++);
 192         if (!(p = nlm4_decode_lock(p, &argp->lock)))
 193                 return 0;
 194         if (exclusive)
 195                 argp->lock.fl.fl_type = F_WRLCK;
 196
 197         return xdr_argsize_check(rqstp, p);
 198 }
 199
 200 int
 201 nlm4svc_encode_testres(struct svc_rqst *rqstp, __be32 *p)
 202 {
 203         struct nlm_res *resp = rqstp->rq_resp;
 204
 205         if (!(p = nlm4_encode_testres(p, resp)))
 206                 return 0;
 207         return xdr_ressize_check(rqstp, p);
 208 }
 209
 210 int
 211 nlm4svc_decode_lockargs(struct svc_rqst *rqstp, __be32 *p)
 212 {
 213         struct nlm_args *argp = rqstp->rq_argp;
 214         u32     exclusive;
 215
 216         if (!(p = nlm4_decode_cookie(p, &argp->cookie)))
 217                 return 0;
 218         argp->block  = ntohl(*p++);
 219         exclusive    = ntohl(*p++);
 220         if (!(p = nlm4_decode_lock(p, &argp->lock)))
 221                 return 0;
 222         if (exclusive)
 223                 argp->lock.fl.fl_type = F_WRLCK;
 224         argp->reclaim = ntohl(*p++);
 225         argp->state   = ntohl(*p++);
 226         argp->monitor = 1;              /* monitor client by default */
 227
 228         return xdr_argsize_check(rqstp, p);
 229 }
 230
 231 int
 232 nlm4svc_decode_cancargs(struct svc_rqst *rqstp, __be32 *p)
 233 {
 234         struct nlm_args *argp = rqstp->rq_argp;
 235         u32     exclusive;
 236
 237         if (!(p = nlm4_decode_cookie(p, &argp->cookie)))
 238                 return 0;
 239         argp->block = ntohl(*p++);
 240         exclusive = ntohl(*p++);
 241         if (!(p = nlm4_decode_lock(p, &argp->lock)))
 242                 return 0;
 243         if (exclusive)
 244                 argp->lock.fl.fl_type = F_WRLCK;
 245         return xdr_argsize_check(rqstp, p);
 246 }
 247
 248 int
 249 nlm4svc_decode_unlockargs(struct svc_rqst *rqstp, __be32 *p)
 250 {
 251         struct nlm_args *argp = rqstp->rq_argp;
 252
 253         if (!(p = nlm4_decode_cookie(p, &argp->cookie))
 254          || !(p = nlm4_decode_lock(p, &argp->lock)))
 255                 return 0;
 256         argp->lock.fl.fl_type = F_UNLCK;
 257         return xdr_argsize_check(rqstp, p);
 258 }
 259
 260 int
 261 nlm4svc_decode_shareargs(struct svc_rqst *rqstp, __be32 *p)
 262 {
 263         struct nlm_args *argp = rqstp->rq_argp;
 264         struct nlm_lock *lock = &argp->lock;
 265
 266         memset(lock, 0, sizeof(*lock));
 267         locks_init_lock(&lock->fl);
 268         lock->svid = ~(u32) 0;
 269         lock->fl.fl_pid = (pid_t)lock->svid;
 270
 271         if (!(p = nlm4_decode_cookie(p, &argp->cookie))
 272          || !(p = xdr_decode_string_inplace(p, &lock->caller,
 273                                             &lock->len, NLM_MAXSTRLEN))
 274          || !(p = nlm4_decode_fh(p, &lock->fh))
 275          || !(p = nlm4_decode_oh(p, &lock->oh)))
 276                 return 0;
 277         argp->fsm_mode = ntohl(*p++);
 278         argp->fsm_access = ntohl(*p++);
 279         return xdr_argsize_check(rqstp, p);
 280 }
 281
 282 int
 283 nlm4svc_encode_shareres(struct svc_rqst *rqstp, __be32 *p)
 284 {
 285         struct nlm_res *resp = rqstp->rq_resp;
 286
 287         if (!(p = nlm4_encode_cookie(p, &resp->cookie)))
 288                 return 0;
 289         *p++ = resp->status;
 290         *p++ = xdr_zero;                /* sequence argument */
 291         return xdr_ressize_check(rqstp, p);
 292 }
 293
 294 int
 295 nlm4svc_encode_res(struct svc_rqst *rqstp, __be32 *p)
 296 {
 297         struct nlm_res *resp = rqstp->rq_resp;
 298
 299         if (!(p = nlm4_encode_cookie(p, &resp->cookie)))
 300                 return 0;
 301         *p++ = resp->status;
 302         return xdr_ressize_check(rqstp, p);
 303 }
 304
 305 int
 306 nlm4svc_decode_notify(struct svc_rqst *rqstp, __be32 *p)
 307 {
 308         struct nlm_args *argp = rqstp->rq_argp;
 309         struct nlm_lock *lock = &argp->lock;
 310
 311         if (!(p = xdr_decode_string_inplace(p, &lock->caller,
 312                                             &lock->len, NLM_MAXSTRLEN)))
 313                 return 0;
 314         argp->state = ntohl(*p++);
 315         return xdr_argsize_check(rqstp, p);
 316 }
 317
 318 int
 319 nlm4svc_decode_reboot(struct svc_rqst *rqstp, __be32 *p)
 320 {
 321         struct nlm_reboot *argp = rqstp->rq_argp;
 322
 323         if (!(p = xdr_decode_string_inplace(p, &argp->mon, &argp->len, SM_MAXSTRLEN)))
 324                 return 0;
 325         argp->state = ntohl(*p++);
 326         memcpy(&argp->priv.data, p, sizeof(argp->priv.data));
 327         p += XDR_QUADLEN(SM_PRIV_SIZE);
 328         return xdr_argsize_check(rqstp, p);
 329 }
 330
 331 int
 332 nlm4svc_decode_res(struct svc_rqst *rqstp, __be32 *p)
 333 {
 334         struct nlm_res *resp = rqstp->rq_argp;
 335
 336         if (!(p = nlm4_decode_cookie(p, &resp->cookie)))
 337                 return 0;
 338         resp->status = *p++;
 339         return xdr_argsize_check(rqstp, p);
 340 }
 341
 342 int
 343 nlm4svc_decode_void(struct svc_rqst *rqstp, __be32 *p)
 344 {
 345         return xdr_argsize_check(rqstp, p);
 346 }
 347
 348 int
 349 nlm4svc_encode_void(struct svc_rqst *rqstp, __be32 *p)
 350 {
 351         return xdr_ressize_check(rqstp, p);
 352 }