src/pxar/flags.rs

   1 //! Feature flags for *pxar* allow to control what is stored/restored in/from the
   2 //! archive.
   3 //! Flags for known supported features for a given filesystem can be derived
   4 //! from the superblocks magic number.
   5
   6 /// FAT-style 2s time granularity
   7 pub const WITH_2SEC_TIME: u64                   = 0x40;
   8 /// Preserve read only flag of files
   9 pub const WITH_READ_ONLY: u64                   = 0x80;
  10 /// Preserve unix permissions
  11 pub const WITH_PERMISSIONS: u64                 = 0x100;
  12 /// Include symbolik links
  13 pub const WITH_SYMLINKS: u64                    = 0x200;
  14 /// Include device nodes
  15 pub const WITH_DEVICE_NODES: u64                = 0x400;
  16 /// Include FIFOs
  17 pub const WITH_FIFOS: u64                       = 0x800;
  18 /// Include Sockets
  19 pub const WITH_SOCKETS: u64                     = 0x1000;
  20
  21 /// Preserve DOS file flag `HIDDEN`
  22 pub const WITH_FLAG_HIDDEN: u64                 = 0x2000;
  23 /// Preserve DOS file flag `SYSTEM`
  24 pub const WITH_FLAG_SYSTEM: u64                 = 0x4000;
  25 /// Preserve DOS file flag `ARCHIVE`
  26 pub const WITH_FLAG_ARCHIVE: u64                = 0x8000;
  27
  28 // chattr() flags
  29 /// Linux file attribute `APPEND`
  30 pub const WITH_FLAG_APPEND: u64                 = 0x10000;
  31 /// Linux file attribute `NOATIME`
  32 pub const WITH_FLAG_NOATIME: u64                = 0x20000;
  33 /// Linux file attribute `COMPR`
  34 pub const WITH_FLAG_COMPR: u64                  = 0x40000;
  35 /// Linux file attribute `NOCOW`
  36 pub const WITH_FLAG_NOCOW: u64                  = 0x80000;
  37 /// Linux file attribute `NODUMP`
  38 pub const WITH_FLAG_NODUMP: u64                 = 0x100000;
  39 /// Linux file attribute `DIRSYNC`
  40 pub const WITH_FLAG_DIRSYNC: u64                = 0x200000;
  41 /// Linux file attribute `IMMUTABLE`
  42 pub const WITH_FLAG_IMMUTABLE: u64              = 0x400000;
  43 /// Linux file attribute `SYNC`
  44 pub const WITH_FLAG_SYNC: u64                   = 0x800000;
  45 /// Linux file attribute `NOCOMP`
  46 pub const WITH_FLAG_NOCOMP: u64                 = 0x1000000;
  47 /// Linux file attribute `PROJINHERIT`
  48 pub const WITH_FLAG_PROJINHERIT: u64            = 0x2000000;
  49
  50
  51 /// Preserve BTRFS subvolume flag
  52 pub const WITH_SUBVOLUME: u64                   = 0x4000000;
  53 /// Preserve BTRFS read-only subvolume flag
  54 pub const WITH_SUBVOLUME_RO: u64                = 0x8000000;
  55
  56 /// Preserve Extended Attribute metadata
  57 pub const WITH_XATTRS: u64                      = 0x10000000;
  58 /// Preserve Access Control List metadata
  59 pub const WITH_ACL: u64                         = 0x20000000;
  60 /// Preserve SELinux security context
  61 pub const WITH_SELINUX: u64                     = 0x40000000;
  62 /// Preserve "security.capability" xattr
  63 pub const WITH_FCAPS: u64                       = 0x80000000;
  64
  65 /// Preserve XFS/ext4/ZFS project quota ID
  66 pub const WITH_QUOTA_PROJID: u64                = 0x100000000;
  67
  68 /// Support ".pxarexclude" files
  69 pub const EXCLUDE_FILE: u64                     = 0x1000000000000000;
  70 /// the purpose of this flag is still unclear
  71 pub const SHA512_256: u64                       = 0x2000000000000000;
  72 /// Exclude submounts
  73 pub const EXCLUDE_SUBMOUNTS: u64                = 0x4000000000000000;
  74 /// Exclude entries with chattr flag NODUMP
  75 pub const EXCLUDE_NODUMP: u64                   = 0x8000000000000000;
  76
  77 /// Definitions of typical feature flags for the *pxar* encoder/decoder.
  78 /// By this expensive syscalls for unsupported features are avoided.
  79
  80 /// All chattr file attributes
  81 pub const WITH_CHATTR: u64 =
  82     WITH_FLAG_APPEND|
  83     WITH_FLAG_NOATIME|
  84     WITH_FLAG_COMPR|
  85     WITH_FLAG_NOCOW|
  86     WITH_FLAG_NODUMP|
  87     WITH_FLAG_DIRSYNC|
  88     WITH_FLAG_IMMUTABLE|
  89     WITH_FLAG_SYNC|
  90     WITH_FLAG_NOCOMP|
  91     WITH_FLAG_PROJINHERIT;
  92
  93 /// All FAT file attributes
  94 pub const WITH_FAT_ATTRS: u64 =
  95     WITH_FLAG_HIDDEN|
  96     WITH_FLAG_SYSTEM|
  97     WITH_FLAG_ARCHIVE;
  98
  99 /// All bits that may also be exposed via fuse
 100 pub const WITH_FUSE: u64 =
 101     WITH_2SEC_TIME|
 102     WITH_READ_ONLY|
 103     WITH_PERMISSIONS|
 104     WITH_SYMLINKS|
 105     WITH_DEVICE_NODES|
 106     WITH_FIFOS|
 107     WITH_SOCKETS|
 108     WITH_FAT_ATTRS|
 109     WITH_CHATTR|
 110     WITH_XATTRS;
 111
 112
 113 /// Default feature flags for encoder/decoder
 114 pub const DEFAULT: u64 =
 115     WITH_SYMLINKS|
 116     WITH_DEVICE_NODES|
 117     WITH_FIFOS|
 118     WITH_SOCKETS|
 119     WITH_FLAG_HIDDEN|
 120     WITH_FLAG_SYSTEM|
 121     WITH_FLAG_ARCHIVE|
 122     WITH_FLAG_APPEND|
 123     WITH_FLAG_NOATIME|
 124     WITH_FLAG_COMPR|
 125     WITH_FLAG_NOCOW|
 126     //WITH_FLAG_NODUMP|
 127     WITH_FLAG_DIRSYNC|
 128     WITH_FLAG_IMMUTABLE|
 129     WITH_FLAG_SYNC|
 130     WITH_FLAG_NOCOMP|
 131     WITH_FLAG_PROJINHERIT|
 132     WITH_SUBVOLUME|
 133     WITH_SUBVOLUME_RO|
 134     WITH_XATTRS|
 135     WITH_ACL|
 136     WITH_SELINUX|
 137     WITH_FCAPS|
 138     WITH_QUOTA_PROJID|
 139     EXCLUDE_NODUMP|
 140     EXCLUDE_FILE|
 141     SHA512_256;
 142
 143 // form /usr/include/linux/fs.h
 144 const FS_APPEND_FL: u32 =      0x00000020;
 145 const FS_NOATIME_FL: u32 =     0x00000080;
 146 const FS_COMPR_FL: u32 =       0x00000004;
 147 const FS_NOCOW_FL: u32 =       0x00800000;
 148 const FS_NODUMP_FL: u32 =      0x00000040;
 149 const FS_DIRSYNC_FL: u32 =     0x00010000;
 150 const FS_IMMUTABLE_FL: u32 =   0x00000010;
 151 const FS_SYNC_FL: u32 =        0x00000008;
 152 const FS_NOCOMP_FL: u32 =      0x00000400;
 153 const FS_PROJINHERIT_FL: u32 = 0x20000000;
 154
 155 static CHATTR_MAP: [(u64, u32); 10] = [
 156     ( WITH_FLAG_APPEND,      FS_APPEND_FL      ),
 157     ( WITH_FLAG_NOATIME,     FS_NOATIME_FL     ),
 158     ( WITH_FLAG_COMPR,       FS_COMPR_FL       ),
 159     ( WITH_FLAG_NOCOW,       FS_NOCOW_FL       ),
 160     ( WITH_FLAG_NODUMP,      FS_NODUMP_FL      ),
 161     ( WITH_FLAG_DIRSYNC,     FS_DIRSYNC_FL     ),
 162     ( WITH_FLAG_IMMUTABLE,   FS_IMMUTABLE_FL   ),
 163     ( WITH_FLAG_SYNC,        FS_SYNC_FL        ),
 164     ( WITH_FLAG_NOCOMP,      FS_NOCOMP_FL      ),
 165     ( WITH_FLAG_PROJINHERIT, FS_PROJINHERIT_FL ),
 166 ];
 167
 168 pub fn feature_flags_from_chattr(attr: u32) -> u64 {
 169
 170     let mut flags = 0u64;
 171
 172     for (fe_flag, fs_flag) in &CHATTR_MAP {
 173         if (attr & fs_flag) != 0 { flags = flags | fe_flag; }
 174     }
 175
 176     flags
 177 }
 178
 179 // from /usr/include/linux/msdos_fs.h
 180 const ATTR_HIDDEN: u32 =      2;
 181 const ATTR_SYS: u32 =         4;
 182 const ATTR_ARCH: u32 =       32;
 183
 184 static FAT_ATTR_MAP: [(u64, u32); 3] = [
 185     ( WITH_FLAG_HIDDEN,  ATTR_HIDDEN ),
 186     ( WITH_FLAG_SYSTEM,  ATTR_SYS    ),
 187     ( WITH_FLAG_ARCHIVE, ATTR_ARCH   ),
 188 ];
 189
 190 pub fn feature_flags_from_fat_attr(attr: u32) -> u64 {
 191
 192     let mut flags = 0u64;
 193
 194     for (fe_flag, fs_flag) in &FAT_ATTR_MAP {
 195         if (attr & fs_flag) != 0 { flags = flags | fe_flag; }
 196     }
 197
 198     flags
 199 }
 200
 201
 202 /// Return the supported *pxar* feature flags based on the magic number of the filesystem.
 203 pub fn feature_flags_from_magic(magic: i64) -> u64 {
 204     use crate::tools::fs::magic::*;
 205     match magic {
 206         MSDOS_SUPER_MAGIC => {
 207             WITH_2SEC_TIME|
 208             WITH_READ_ONLY|
 209             WITH_FAT_ATTRS
 210         },
 211         EXT4_SUPER_MAGIC => {
 212             WITH_2SEC_TIME|
 213             WITH_READ_ONLY|
 214             WITH_PERMISSIONS|
 215             WITH_SYMLINKS|
 216             WITH_DEVICE_NODES|
 217             WITH_FIFOS|
 218             WITH_SOCKETS|
 219             WITH_FLAG_APPEND|
 220             WITH_FLAG_NOATIME|
 221             WITH_FLAG_NODUMP|
 222             WITH_FLAG_DIRSYNC|
 223             WITH_FLAG_IMMUTABLE|
 224             WITH_FLAG_SYNC|
 225             WITH_XATTRS|
 226             WITH_ACL|
 227             WITH_SELINUX|
 228             WITH_FCAPS|
 229             WITH_QUOTA_PROJID
 230         },
 231         XFS_SUPER_MAGIC => {
 232             WITH_2SEC_TIME|
 233             WITH_READ_ONLY|
 234             WITH_PERMISSIONS|
 235             WITH_SYMLINKS|
 236             WITH_DEVICE_NODES|
 237             WITH_FIFOS|
 238             WITH_SOCKETS|
 239             WITH_FLAG_APPEND|
 240             WITH_FLAG_NOATIME|
 241             WITH_FLAG_NODUMP|
 242             WITH_FLAG_IMMUTABLE|
 243             WITH_FLAG_SYNC|
 244             WITH_XATTRS|
 245             WITH_ACL|
 246             WITH_SELINUX|
 247             WITH_FCAPS|
 248             WITH_QUOTA_PROJID
 249         },
 250         ZFS_SUPER_MAGIC => {
 251             WITH_2SEC_TIME|
 252             WITH_READ_ONLY|
 253             WITH_PERMISSIONS|
 254             WITH_SYMLINKS|
 255             WITH_DEVICE_NODES|
 256             WITH_FIFOS|
 257             WITH_SOCKETS|
 258             WITH_FLAG_APPEND|
 259             WITH_FLAG_NOATIME|
 260             WITH_FLAG_NODUMP|
 261             WITH_FLAG_DIRSYNC|
 262             WITH_FLAG_IMMUTABLE|
 263             WITH_FLAG_SYNC|
 264             WITH_XATTRS|
 265             WITH_ACL|
 266             WITH_SELINUX|
 267             WITH_FCAPS|
 268             WITH_QUOTA_PROJID
 269         },
 270         BTRFS_SUPER_MAGIC => {
 271             WITH_2SEC_TIME|
 272             WITH_READ_ONLY|
 273             WITH_PERMISSIONS|
 274             WITH_SYMLINKS|
 275             WITH_DEVICE_NODES|
 276             WITH_FIFOS|
 277             WITH_SOCKETS|
 278             WITH_FLAG_APPEND|
 279             WITH_FLAG_NOATIME|
 280             WITH_FLAG_COMPR|
 281             WITH_FLAG_NOCOW|
 282             WITH_FLAG_NODUMP|
 283             WITH_FLAG_DIRSYNC|
 284             WITH_FLAG_IMMUTABLE|
 285             WITH_FLAG_SYNC|
 286             WITH_FLAG_NOCOMP|
 287             WITH_XATTRS|
 288             WITH_ACL|
 289             WITH_SELINUX|
 290             WITH_SUBVOLUME|
 291             WITH_SUBVOLUME_RO|
 292             WITH_FCAPS
 293         },
 294         TMPFS_MAGIC => {
 295             WITH_2SEC_TIME|
 296             WITH_READ_ONLY|
 297             WITH_PERMISSIONS|
 298             WITH_SYMLINKS|
 299             WITH_DEVICE_NODES|
 300             WITH_FIFOS|
 301             WITH_SOCKETS|
 302             WITH_ACL|
 303             WITH_SELINUX
 304         },
 305         // FUSE mounts are special as the supported feature set
 306         // is not clear a priori.
 307         FUSE_SUPER_MAGIC => {
 308             WITH_FUSE
 309         },
 310         _ => {
 311             WITH_2SEC_TIME|
 312             WITH_READ_ONLY|
 313             WITH_PERMISSIONS|
 314             WITH_SYMLINKS|
 315             WITH_DEVICE_NODES|
 316             WITH_FIFOS|
 317             WITH_SOCKETS
 318         },
 319     }
 320 }