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_flags = FL_POSIX;
 130         fl->fl_type  = F_RDLCK;         /* as good as anything else */
 131         start = ntohl(*p++);
 132         len = ntohl(*p++);
 133         end = start + len - 1;
 134
 135         fl->fl_start = s32_to_loff_t(start);
 136
 137         if (len == 0 || end < 0)
 138                 fl->fl_end = OFFSET_MAX;
 139         else
 140                 fl->fl_end = s32_to_loff_t(end);
 141         return p;
 142 }
 143
 144 /*
 145  * Encode result of a TEST/TEST_MSG call
 146  */
 147 static __be32 *
 148 nlm_encode_testres(__be32 *p, struct nlm_res *resp)
 149 {
 150         s32             start, len;
 151
 152         if (!(p = nlm_encode_cookie(p, &resp->cookie)))
 153                 return NULL;
 154         *p++ = resp->status;
 155
 156         if (resp->status == nlm_lck_denied) {
 157                 struct file_lock        *fl = &resp->lock.fl;
 158
 159                 *p++ = (fl->fl_type == F_RDLCK)? xdr_zero : xdr_one;
 160                 *p++ = htonl(resp->lock.svid);
 161
 162                 /* Encode owner handle. */
 163                 if (!(p = xdr_encode_netobj(p, &resp->lock.oh)))
 164                         return NULL;
 165
 166                 start = loff_t_to_s32(fl->fl_start);
 167                 if (fl->fl_end == OFFSET_MAX)
 168                         len = 0;
 169                 else
 170                         len = loff_t_to_s32(fl->fl_end - fl->fl_start + 1);
 171
 172                 *p++ = htonl(start);
 173                 *p++ = htonl(len);
 174         }
 175
 176         return p;
 177 }
 178
 179
 180 /*
 181  * First, the server side XDR functions
 182  */
 183 int
 184 nlmsvc_decode_testargs(struct svc_rqst *rqstp, __be32 *p)
 185 {
 186         struct nlm_args *argp = rqstp->rq_argp;
 187         u32     exclusive;
 188
 189         if (!(p = nlm_decode_cookie(p, &argp->cookie)))
 190                 return 0;
 191
 192         exclusive = ntohl(*p++);
 193         if (!(p = nlm_decode_lock(p, &argp->lock)))
 194                 return 0;
 195         if (exclusive)
 196                 argp->lock.fl.fl_type = F_WRLCK;
 197
 198         return xdr_argsize_check(rqstp, p);
 199 }
 200
 201 int
 202 nlmsvc_encode_testres(struct svc_rqst *rqstp, __be32 *p)
 203 {
 204         struct nlm_res *resp = rqstp->rq_resp;
 205
 206         if (!(p = nlm_encode_testres(p, resp)))
 207                 return 0;
 208         return xdr_ressize_check(rqstp, p);
 209 }
 210
 211 int
 212 nlmsvc_decode_lockargs(struct svc_rqst *rqstp, __be32 *p)
 213 {
 214         struct nlm_args *argp = rqstp->rq_argp;
 215         u32     exclusive;
 216
 217         if (!(p = nlm_decode_cookie(p, &argp->cookie)))
 218                 return 0;
 219         argp->block  = ntohl(*p++);
 220         exclusive    = ntohl(*p++);
 221         if (!(p = nlm_decode_lock(p, &argp->lock)))
 222                 return 0;
 223         if (exclusive)
 224                 argp->lock.fl.fl_type = F_WRLCK;
 225         argp->reclaim = ntohl(*p++);
 226         argp->state   = ntohl(*p++);
 227         argp->monitor = 1;              /* monitor client by default */
 228
 229         return xdr_argsize_check(rqstp, p);
 230 }
 231
 232 int
 233 nlmsvc_decode_cancargs(struct svc_rqst *rqstp, __be32 *p)
 234 {
 235         struct nlm_args *argp = rqstp->rq_argp;
 236         u32     exclusive;
 237
 238         if (!(p = nlm_decode_cookie(p, &argp->cookie)))
 239                 return 0;
 240         argp->block = ntohl(*p++);
 241         exclusive = ntohl(*p++);
 242         if (!(p = nlm_decode_lock(p, &argp->lock)))
 243                 return 0;
 244         if (exclusive)
 245                 argp->lock.fl.fl_type = F_WRLCK;
 246         return xdr_argsize_check(rqstp, p);
 247 }
 248
 249 int
 250 nlmsvc_decode_unlockargs(struct svc_rqst *rqstp, __be32 *p)
 251 {
 252         struct nlm_args *argp = rqstp->rq_argp;
 253
 254         if (!(p = nlm_decode_cookie(p, &argp->cookie))
 255          || !(p = nlm_decode_lock(p, &argp->lock)))
 256                 return 0;
 257         argp->lock.fl.fl_type = F_UNLCK;
 258         return xdr_argsize_check(rqstp, p);
 259 }
 260
 261 int
 262 nlmsvc_decode_shareargs(struct svc_rqst *rqstp, __be32 *p)
 263 {
 264         struct nlm_args *argp = rqstp->rq_argp;
 265         struct nlm_lock *lock = &argp->lock;
 266
 267         memset(lock, 0, sizeof(*lock));
 268         locks_init_lock(&lock->fl);
 269         lock->svid = ~(u32) 0;
 270
 271         if (!(p = nlm_decode_cookie(p, &argp->cookie))
 272          || !(p = xdr_decode_string_inplace(p, &lock->caller,
 273                                             &lock->len, NLM_MAXSTRLEN))
 274          || !(p = nlm_decode_fh(p, &lock->fh))
 275          || !(p = nlm_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 nlmsvc_encode_shareres(struct svc_rqst *rqstp, __be32 *p)
 284 {
 285         struct nlm_res *resp = rqstp->rq_resp;
 286
 287         if (!(p = nlm_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 nlmsvc_encode_res(struct svc_rqst *rqstp, __be32 *p)
 296 {
 297         struct nlm_res *resp = rqstp->rq_resp;
 298
 299         if (!(p = nlm_encode_cookie(p, &resp->cookie)))
 300                 return 0;
 301         *p++ = resp->status;
 302         return xdr_ressize_check(rqstp, p);
 303 }
 304
 305 int
 306 nlmsvc_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 nlmsvc_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 nlmsvc_decode_res(struct svc_rqst *rqstp, __be32 *p)
 333 {
 334         struct nlm_res *resp = rqstp->rq_argp;
 335
 336         if (!(p = nlm_decode_cookie(p, &resp->cookie)))
 337                 return 0;
 338         resp->status = *p++;
 339         return xdr_argsize_check(rqstp, p);
 340 }
 341
 342 int
 343 nlmsvc_decode_void(struct svc_rqst *rqstp, __be32 *p)
 344 {
 345         return xdr_argsize_check(rqstp, p);
 346 }
 347
 348 int
 349 nlmsvc_encode_void(struct svc_rqst *rqstp, __be32 *p)
 350 {
 351         return xdr_ressize_check(rqstp, p);
 352 }