fs/nfsd/lockd.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * This file contains all the stubs needed when communicating with lockd.
   4  * This level of indirection is necessary so we can run nfsd+lockd without
   5  * requiring the nfs client to be compiled in/loaded, and vice versa.
   6  *
   7  * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
   8  */
   9
  10 #include <linux/file.h>
  11 #include <linux/lockd/bind.h>
  12 #include "nfsd.h"
  13 #include "vfs.h"
  14
  15 #define NFSDDBG_FACILITY                NFSDDBG_LOCKD
  16
  17 #ifdef CONFIG_LOCKD_V4
  18 #define nlm_stale_fh    nlm4_stale_fh
  19 #define nlm_failed      nlm4_failed
  20 #else
  21 #define nlm_stale_fh    nlm_lck_denied_nolocks
  22 #define nlm_failed      nlm_lck_denied_nolocks
  23 #endif
  24 /*
  25  * Note: we hold the dentry use count while the file is open.
  26  */
  27 static __be32
  28 nlm_fopen(struct svc_rqst *rqstp, struct nfs_fh *f, struct file **filp,
  29                 int mode)
  30 {
  31         __be32          nfserr;
  32         int             access;
  33         struct svc_fh   fh;
  34
  35         /* must initialize before using! but maxsize doesn't matter */
  36         fh_init(&fh,0);
  37         fh.fh_handle.fh_size = f->size;
  38         memcpy(&fh.fh_handle.fh_raw, f->data, f->size);
  39         fh.fh_export = NULL;
  40
  41         /*
  42          * Allow BYPASS_GSS as some client implementations use AUTH_SYS
  43          * for NLM even when GSS is used for NFS.
  44          * Allow OWNER_OVERRIDE as permission might have been changed
  45          * after the file was opened.
  46          * Pass MAY_NLM so that authentication can be completely bypassed
  47          * if NFSEXP_NOAUTHNLM is set.  Some older clients use AUTH_NULL
  48          * for NLM requests.
  49          */
  50         access = (mode == O_WRONLY) ? NFSD_MAY_WRITE : NFSD_MAY_READ;
  51         access |= NFSD_MAY_NLM | NFSD_MAY_OWNER_OVERRIDE | NFSD_MAY_BYPASS_GSS;
  52         nfserr = nfsd_open(rqstp, &fh, S_IFREG, access, filp);
  53         fh_put(&fh);
  54         /* We return nlm error codes as nlm doesn't know
  55          * about nfsd, but nfsd does know about nlm..
  56          */
  57         switch (nfserr) {
  58         case nfs_ok:
  59                 return 0;
  60         case nfserr_dropit:
  61                 return nlm_drop_reply;
  62         case nfserr_stale:
  63                 return nlm_stale_fh;
  64         default:
  65                 return nlm_failed;
  66         }
  67 }
  68
  69 static void
  70 nlm_fclose(struct file *filp)
  71 {
  72         fput(filp);
  73 }
  74
  75 static const struct nlmsvc_binding nfsd_nlm_ops = {
  76         .fopen          = nlm_fopen,            /* open file for locking */
  77         .fclose         = nlm_fclose,           /* close file */
  78 };
  79
  80 void
  81 nfsd_lockd_init(void)
  82 {
  83         dprintk("nfsd: initializing lockd\n");
  84         nlmsvc_ops = &nfsd_nlm_ops;
  85 }
  86
  87 void
  88 nfsd_lockd_shutdown(void)
  89 {
  90         nlmsvc_ops = NULL;
  91 }