fs/nfsd/nfs3acl.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Process version 3 NFSACL requests.
   4  *
   5  * Copyright (C) 2002-2003 Andreas Gruenbacher <agruen@suse.de>
   6  */
   7
   8 #include "nfsd.h"
   9 /* FIXME: nfsacl.h is a broken header */
  10 #include <linux/nfsacl.h>
  11 #include <linux/gfp.h>
  12 #include "cache.h"
  13 #include "xdr3.h"
  14 #include "vfs.h"
  15
  16 /*
  17  * NULL call.
  18  */
  19 static __be32
  20 nfsd3_proc_null(struct svc_rqst *rqstp)
  21 {
  22         return rpc_success;
  23 }
  24
  25 /*
  26  * Get the Access and/or Default ACL of a file.
  27  */
  28 static __be32 nfsd3_proc_getacl(struct svc_rqst *rqstp)
  29 {
  30         struct nfsd3_getaclargs *argp = rqstp->rq_argp;
  31         struct nfsd3_getaclres *resp = rqstp->rq_resp;
  32         struct posix_acl *acl;
  33         struct inode *inode;
  34         svc_fh *fh;
  35
  36         fh = fh_copy(&resp->fh, &argp->fh);
  37         resp->status = fh_verify(rqstp, &resp->fh, 0, NFSD_MAY_NOP);
  38         if (resp->status != nfs_ok)
  39                 goto out;
  40
  41         inode = d_inode(fh->fh_dentry);
  42
  43         if (argp->mask & ~NFS_ACL_MASK) {
  44                 resp->status = nfserr_inval;
  45                 goto out;
  46         }
  47         resp->mask = argp->mask;
  48
  49         if (resp->mask & (NFS_ACL|NFS_ACLCNT)) {
  50                 acl = get_acl(inode, ACL_TYPE_ACCESS);
  51                 if (acl == NULL) {
  52                         /* Solaris returns the inode's minimum ACL. */
  53                         acl = posix_acl_from_mode(inode->i_mode, GFP_KERNEL);
  54                 }
  55                 if (IS_ERR(acl)) {
  56                         resp->status = nfserrno(PTR_ERR(acl));
  57                         goto fail;
  58                 }
  59                 resp->acl_access = acl;
  60         }
  61         if (resp->mask & (NFS_DFACL|NFS_DFACLCNT)) {
  62                 /* Check how Solaris handles requests for the Default ACL
  63                    of a non-directory! */
  64                 acl = get_acl(inode, ACL_TYPE_DEFAULT);
  65                 if (IS_ERR(acl)) {
  66                         resp->status = nfserrno(PTR_ERR(acl));
  67                         goto fail;
  68                 }
  69                 resp->acl_default = acl;
  70         }
  71
  72         /* resp->acl_{access,default} are released in nfs3svc_release_getacl. */
  73 out:
  74         return rpc_success;
  75
  76 fail:
  77         posix_acl_release(resp->acl_access);
  78         posix_acl_release(resp->acl_default);
  79         goto out;
  80 }
  81
  82 /*
  83  * Set the Access and/or Default ACL of a file.
  84  */
  85 static __be32 nfsd3_proc_setacl(struct svc_rqst *rqstp)
  86 {
  87         struct nfsd3_setaclargs *argp = rqstp->rq_argp;
  88         struct nfsd3_attrstat *resp = rqstp->rq_resp;
  89         struct inode *inode;
  90         svc_fh *fh;
  91         int error;
  92
  93         fh = fh_copy(&resp->fh, &argp->fh);
  94         resp->status = fh_verify(rqstp, &resp->fh, 0, NFSD_MAY_SATTR);
  95         if (resp->status != nfs_ok)
  96                 goto out;
  97
  98         inode = d_inode(fh->fh_dentry);
  99
 100         error = fh_want_write(fh);
 101         if (error)
 102                 goto out_errno;
 103
 104         fh_lock(fh);
 105
 106         error = set_posix_acl(inode, ACL_TYPE_ACCESS, argp->acl_access);
 107         if (error)
 108                 goto out_drop_lock;
 109         error = set_posix_acl(inode, ACL_TYPE_DEFAULT, argp->acl_default);
 110
 111 out_drop_lock:
 112         fh_unlock(fh);
 113         fh_drop_write(fh);
 114 out_errno:
 115         resp->status = nfserrno(error);
 116 out:
 117         /* argp->acl_{access,default} may have been allocated in
 118            nfs3svc_decode_setaclargs. */
 119         posix_acl_release(argp->acl_access);
 120         posix_acl_release(argp->acl_default);
 121         return rpc_success;
 122 }
 123
 124 /*
 125  * XDR decode functions
 126  */
 127 static int nfs3svc_decode_getaclargs(struct svc_rqst *rqstp, __be32 *p)
 128 {
 129         struct nfsd3_getaclargs *args = rqstp->rq_argp;
 130
 131         p = nfs3svc_decode_fh(p, &args->fh);
 132         if (!p)
 133                 return 0;
 134         args->mask = ntohl(*p); p++;
 135
 136         return xdr_argsize_check(rqstp, p);
 137 }
 138
 139
 140 static int nfs3svc_decode_setaclargs(struct svc_rqst *rqstp, __be32 *p)
 141 {
 142         struct nfsd3_setaclargs *args = rqstp->rq_argp;
 143         struct kvec *head = rqstp->rq_arg.head;
 144         unsigned int base;
 145         int n;
 146
 147         p = nfs3svc_decode_fh(p, &args->fh);
 148         if (!p)
 149                 return 0;
 150         args->mask = ntohl(*p++);
 151         if (args->mask & ~NFS_ACL_MASK ||
 152             !xdr_argsize_check(rqstp, p))
 153                 return 0;
 154
 155         base = (char *)p - (char *)head->iov_base;
 156         n = nfsacl_decode(&rqstp->rq_arg, base, NULL,
 157                           (args->mask & NFS_ACL) ?
 158                           &args->acl_access : NULL);
 159         if (n > 0)
 160                 n = nfsacl_decode(&rqstp->rq_arg, base + n, NULL,
 161                                   (args->mask & NFS_DFACL) ?
 162                                   &args->acl_default : NULL);
 163         return (n > 0);
 164 }
 165
 166 /*
 167  * XDR encode functions
 168  */
 169
 170 /* GETACL */
 171 static int nfs3svc_encode_getaclres(struct svc_rqst *rqstp, __be32 *p)
 172 {
 173         struct nfsd3_getaclres *resp = rqstp->rq_resp;
 174         struct dentry *dentry = resp->fh.fh_dentry;
 175
 176         *p++ = resp->status;
 177         p = nfs3svc_encode_post_op_attr(rqstp, p, &resp->fh);
 178         if (resp->status == 0 && dentry && d_really_is_positive(dentry)) {
 179                 struct inode *inode = d_inode(dentry);
 180                 struct kvec *head = rqstp->rq_res.head;
 181                 unsigned int base;
 182                 int n;
 183                 int w;
 184
 185                 *p++ = htonl(resp->mask);
 186                 if (!xdr_ressize_check(rqstp, p))
 187                         return 0;
 188                 base = (char *)p - (char *)head->iov_base;
 189
 190                 rqstp->rq_res.page_len = w = nfsacl_size(
 191                         (resp->mask & NFS_ACL)   ? resp->acl_access  : NULL,
 192                         (resp->mask & NFS_DFACL) ? resp->acl_default : NULL);
 193                 while (w > 0) {
 194                         if (!*(rqstp->rq_next_page++))
 195                                 return 0;
 196                         w -= PAGE_SIZE;
 197                 }
 198
 199                 n = nfsacl_encode(&rqstp->rq_res, base, inode,
 200                                   resp->acl_access,
 201                                   resp->mask & NFS_ACL, 0);
 202                 if (n > 0)
 203                         n = nfsacl_encode(&rqstp->rq_res, base + n, inode,
 204                                           resp->acl_default,
 205                                           resp->mask & NFS_DFACL,
 206                                           NFS_ACL_DEFAULT);
 207                 if (n <= 0)
 208                         return 0;
 209         } else
 210                 if (!xdr_ressize_check(rqstp, p))
 211                         return 0;
 212
 213         return 1;
 214 }
 215
 216 /* SETACL */
 217 static int nfs3svc_encode_setaclres(struct svc_rqst *rqstp, __be32 *p)
 218 {
 219         struct nfsd3_attrstat *resp = rqstp->rq_resp;
 220
 221         *p++ = resp->status;
 222         p = nfs3svc_encode_post_op_attr(rqstp, p, &resp->fh);
 223         return xdr_ressize_check(rqstp, p);
 224 }
 225
 226 /*
 227  * XDR release functions
 228  */
 229 static void nfs3svc_release_getacl(struct svc_rqst *rqstp)
 230 {
 231         struct nfsd3_getaclres *resp = rqstp->rq_resp;
 232
 233         fh_put(&resp->fh);
 234         posix_acl_release(resp->acl_access);
 235         posix_acl_release(resp->acl_default);
 236 }
 237
 238 struct nfsd3_voidargs { int dummy; };
 239
 240 #define ST 1            /* status*/
 241 #define AT 21           /* attributes */
 242 #define pAT (1+AT)      /* post attributes - conditional */
 243 #define ACL (1+NFS_ACL_MAX_ENTRIES*3)  /* Access Control List */
 244
 245 static const struct svc_procedure nfsd_acl_procedures3[3] = {
 246         [ACLPROC3_NULL] = {
 247                 .pc_func = nfsd3_proc_null,
 248                 .pc_decode = nfssvc_decode_voidarg,
 249                 .pc_encode = nfssvc_encode_voidres,
 250                 .pc_argsize = sizeof(struct nfsd_voidargs),
 251                 .pc_ressize = sizeof(struct nfsd_voidres),
 252                 .pc_cachetype = RC_NOCACHE,
 253                 .pc_xdrressize = ST,
 254         },
 255         [ACLPROC3_GETACL] = {
 256                 .pc_func = nfsd3_proc_getacl,
 257                 .pc_decode = nfs3svc_decode_getaclargs,
 258                 .pc_encode = nfs3svc_encode_getaclres,
 259                 .pc_release = nfs3svc_release_getacl,
 260                 .pc_argsize = sizeof(struct nfsd3_getaclargs),
 261                 .pc_ressize = sizeof(struct nfsd3_getaclres),
 262                 .pc_cachetype = RC_NOCACHE,
 263                 .pc_xdrressize = ST+1+2*(1+ACL),
 264         },
 265         [ACLPROC3_SETACL] = {
 266                 .pc_func = nfsd3_proc_setacl,
 267                 .pc_decode = nfs3svc_decode_setaclargs,
 268                 .pc_encode = nfs3svc_encode_setaclres,
 269                 .pc_release = nfs3svc_release_fhandle,
 270                 .pc_argsize = sizeof(struct nfsd3_setaclargs),
 271                 .pc_ressize = sizeof(struct nfsd3_attrstat),
 272                 .pc_cachetype = RC_NOCACHE,
 273                 .pc_xdrressize = ST+pAT,
 274         },
 275 };
 276
 277 static unsigned int nfsd_acl_count3[ARRAY_SIZE(nfsd_acl_procedures3)];
 278 const struct svc_version nfsd_acl_version3 = {
 279         .vs_vers        = 3,
 280         .vs_nproc       = 3,
 281         .vs_proc        = nfsd_acl_procedures3,
 282         .vs_count       = nfsd_acl_count3,
 283         .vs_dispatch    = nfsd_dispatch,
 284         .vs_xdrsize     = NFS3_SVC_XDRSIZE,
 285 };
 286