[pxar.git] / src / format.rs

//! *pxar* binary format definition
//!
//! Please note the all values are stored in little endian ordering.
//!
//! The Archive contains a list of items. Each item starts with a `Header`, followed by the
//! item data.

use std::cmp::Ordering;
use std::ffi::{CStr, OsStr};
use std::io;
use std::mem::size_of;
use std::os::unix::ffi::OsStrExt;
use std::path::Path;

use endian_trait::Endian;
use siphasher::sip::SipHasher24;

pub mod acl;

/// While these constants correspond to `libc::S_` constants, we need these to be fixed for the
/// format itself, so we redefine them here.
///
/// Additionally this gets rid of a bunch of casts between u32 and u64.
///
/// You can usually find the values for these in `/usr/include/linux/stat.h`.
#[rustfmt::skip]
pub mod mode {
    pub const IFMT   : u64 = 0o0170000;

    pub const IFSOCK : u64 = 0o0140000;
    pub const IFLNK  : u64 = 0o0120000;
    pub const IFREG  : u64 = 0o0100000;
    pub const IFBLK  : u64 = 0o0060000;
    pub const IFDIR  : u64 = 0o0040000;
    pub const IFCHR  : u64 = 0o0020000;
    pub const IFIFO  : u64 = 0o0010000;

    pub const ISUID  : u64 = 0o0004000;
    pub const ISGID  : u64 = 0o0002000;
    pub const ISVTX  : u64 = 0o0001000;
}

pub const PXAR_ENTRY: u64 = 0x1396fabcea5bbb51;
pub const PXAR_FILENAME: u64 = 0x6dbb6ebcb3161f0b;
pub const PXAR_SYMLINK: u64 = 0x664a6fb6830e0d6c;
pub const PXAR_DEVICE: u64 = 0xac3dace369dfe643;
pub const PXAR_XATTR: u64 = 0xb8157091f80bc486;
pub const PXAR_ACL_USER: u64 = 0x297dc88b2ef12faf;
pub const PXAR_ACL_GROUP: u64 = 0x36f2acb56cb3dd0b;
pub const PXAR_ACL_GROUP_OBJ: u64 = 0x23047110441f38f3;
pub const PXAR_ACL_DEFAULT: u64 = 0xfe3eeda6823c8cd0;
pub const PXAR_ACL_DEFAULT_USER: u64 = 0xbdf03df9bd010a91;
pub const PXAR_ACL_DEFAULT_GROUP: u64 = 0xa0cb1168782d1f51;
pub const PXAR_FCAPS: u64 = 0xf7267db0afed0629;
pub const PXAR_QUOTA_PROJID: u64 = 0x161baf2d8772a72b;

/// Marks item as hardlink
/// compute_goodbye_hash(b"__PROXMOX_FORMAT_HARDLINK__");
pub const PXAR_HARDLINK: u64 = 0x2c5e06f634f65b86;
/// Marks the beginnig of the payload (actual content) of regular files
pub const PXAR_PAYLOAD: u64 = 0x8b9e1d93d6dcffc9;
/// Marks item as entry of goodbye table
pub const PXAR_GOODBYE: u64 = 0xdfd35c5e8327c403;
/// The end marker used in the GOODBYE object
pub const PXAR_GOODBYE_TAIL_MARKER: u64 = 0x57446fa533702943;

#[derive(Debug, Endian)]
#[repr(C)]
pub struct Header {
    /// The item type (see `PXAR_` constants).
    pub htype: u64,
    /// The size of the item, including the size of `Header`.
    full_size: u64,
}

impl Header {
    #[inline]
    pub fn with_full_size(htype: u64, full_size: u64) -> Self {
        Self { htype, full_size }
    }

    #[inline]
    pub fn with_content_size(htype: u64, content_size: u64) -> Self {
        Self::with_full_size(htype, content_size + size_of::<Header>() as u64)
    }

    #[inline]
    pub fn full_size(&self) -> u64 {
        self.full_size
    }

    #[inline]
    pub fn content_size(&self) -> u64 {
        self.full_size() - (size_of::<Self>() as u64)
    }
}

#[derive(Clone, Debug, Default, Endian)]
#[repr(C)]
pub struct Entry {
    pub mode: u64,
    pub flags: u64,
    pub uid: u32,
    pub gid: u32,
    pub mtime: u64,
}

/// Builder pattern methods.
impl Entry {
    pub const fn mode(self, mode: u64) -> Self {
        Self { mode, ..self }
    }

    pub const fn flags(self, flags: u64) -> Self {
        Self { flags, ..self }
    }

    pub const fn uid(self, uid: u32) -> Self {
        Self { uid, ..self }
    }

    pub const fn gid(self, gid: u32) -> Self {
        Self { gid, ..self }
    }

    pub const fn mtime(self, mtime: u64) -> Self {
        Self { mtime, ..self }
    }

    pub const fn set_dir(self) -> Self {
        let mode = self.mode;
        self.mode((mode & !mode::IFMT) | mode::IFDIR)
    }

    pub const fn set_regular_file(self) -> Self {
        let mode = self.mode;
        self.mode((mode & !mode::IFMT) | mode::IFREG)
    }

    pub const fn set_symlink(self) -> Self {
        let mode = self.mode;
        self.mode((mode & !mode::IFMT) | mode::IFLNK)
    }

    pub const fn set_blockdev(self) -> Self {
        let mode = self.mode;
        self.mode((mode & !mode::IFMT) | mode::IFBLK)
    }

    pub const fn set_chardev(self) -> Self {
        let mode = self.mode;
        self.mode((mode & !mode::IFMT) | mode::IFCHR)
    }

    pub const fn set_fifo(self) -> Self {
        let mode = self.mode;
        self.mode((mode & !mode::IFMT) | mode::IFIFO)
    }
}

/// Convenience accessor methods.
impl Entry {
    /// Get the mtime as duration since the epoch.
    pub fn mtime_as_duration(&self) -> std::time::Duration {
        std::time::Duration::from_nanos(self.mtime)
    }

    /// Get the file type portion of the mode bitfield.
    pub fn get_file_bits(&self) -> u64 {
        self.mode & mode::IFMT
    }

    /// Get the permission portion of the mode bitfield.
    pub fn get_permission_bits(&self) -> u64 {
        self.mode & !mode::IFMT
    }
}

/// Convenience methods.
impl Entry {
    /// Get the file type (`mode & mode::IFMT`).
    pub fn file_type(&self) -> u64 {
        self.mode & mode::IFMT
    }

    /// Get the file mode bits (`mode & !mode::IFMT`).
    pub fn file_mode(&self) -> u64 {
        self.mode & !mode::IFMT
    }

    /// Check whether this is a directory.
    pub fn is_dir(&self) -> bool {
        (self.mode & mode::IFMT) == mode::IFDIR
    }

    /// Check whether this is a symbolic link.
    pub fn is_symlink(&self) -> bool {
        (self.mode & mode::IFMT) == mode::IFLNK
    }

    /// Check whether this is a device node.
    pub fn is_device(&self) -> bool {
        let fmt = self.mode & mode::IFMT;
        fmt == mode::IFCHR || fmt == mode::IFBLK
    }

    /// Check whether this is a block device node.
    pub fn is_blockdev(&self) -> bool {
        let fmt = self.mode & mode::IFMT;
        fmt == mode::IFBLK
    }

    /// Check whether this is a character device node.
    pub fn is_chardev(&self) -> bool {
        let fmt = self.mode & mode::IFMT;
        fmt == mode::IFCHR
    }

    /// Check whether this is a regular file.
    pub fn is_regular_file(&self) -> bool {
        (self.mode & mode::IFMT) == mode::IFREG
    }

    /// Check whether this is a named pipe (FIFO).
    pub fn is_fifo(&self) -> bool {
        (self.mode & mode::IFMT) == mode::IFIFO
    }

    /// Check whether this is a named socket.
    pub fn is_socket(&self) -> bool {
        (self.mode & mode::IFMT) == mode::IFSOCK
    }
}

impl From<&std::fs::Metadata> for Entry {
    fn from(meta: &std::fs::Metadata) -> Entry {
        #[cfg(unix)]
        use std::os::unix::fs::MetadataExt;

        let this = Entry::default();

        #[cfg(unix)]
        let this = this
            .uid(meta.uid())
            .gid(meta.gid())
            .mode(meta.mode() as u64)
            .mtime(meta.mtime() as u64);

        let file_type = meta.file_type();
        let mode = this.mode;
        let this = if file_type.is_dir() {
            this.mode(mode | mode::IFDIR)
        } else if file_type.is_symlink() {
            this.mode(mode | mode::IFLNK)
        } else {
            this.mode(mode | mode::IFREG)
        };

        this
    }
}

#[derive(Clone, Debug)]
pub struct Filename {
    pub name: Vec<u8>,
}

#[derive(Clone, Debug)]
pub struct Symlink {
    pub data: Vec<u8>,
}

impl Symlink {
    pub fn as_os_str(&self) -> &OsStr {
        self.as_ref()
    }
}

impl AsRef<[u8]> for Symlink {
    fn as_ref(&self) -> &[u8] {
        &self.data
    }
}

impl AsRef<OsStr> for Symlink {
    fn as_ref(&self) -> &OsStr {
        OsStr::from_bytes(&self.data[..self.data.len().max(1) - 1])
    }
}

#[derive(Clone, Debug)]
pub struct Hardlink {
    pub offset: u64,
    pub data: Vec<u8>,
}

impl Hardlink {
    pub fn as_os_str(&self) -> &OsStr {
        self.as_ref()
    }
}

impl AsRef<[u8]> for Hardlink {
    fn as_ref(&self) -> &[u8] {
        &self.data
    }
}

impl AsRef<OsStr> for Hardlink {
    fn as_ref(&self) -> &OsStr {
        OsStr::from_bytes(&self.data[..self.data.len().max(1) - 1])
    }
}

#[derive(Clone, Debug, Eq)]
#[repr(C)]
pub struct XAttr {
    pub(crate) data: Vec<u8>,
    pub(crate) name_len: usize,
}

impl XAttr {
    pub fn new<N: AsRef<[u8]>, V: AsRef<[u8]>>(name: N, value: V) -> Self {
        let name = name.as_ref();
        let value = value.as_ref();
        let mut data = Vec::with_capacity(name.len() + value.len() + 1);
        data.extend(name);
        data.push(0);
        data.extend(value);
        Self {
            data,
            name_len: name.len(),
        }
    }

    pub fn name(&self) -> &CStr {
        unsafe { CStr::from_bytes_with_nul_unchecked(&self.data[..self.name_len + 1]) }
    }

    pub fn value(&self) -> &[u8] {
        &self.data[(self.name_len + 1)..]
    }
}

impl Ord for XAttr {
    fn cmp(&self, other: &XAttr) -> Ordering {
        self.name().cmp(&other.name())
    }
}

impl PartialOrd for XAttr {
    fn partial_cmp(&self, other: &XAttr) -> Option<Ordering> {
        Some(self.cmp(other))
    }
}

impl PartialEq for XAttr {
    fn eq(&self, other: &XAttr) -> bool {
        self.name() == other.name()
    }
}

#[derive(Clone, Debug, Endian)]
#[repr(C)]
pub struct Device {
    pub major: u64,
    pub minor: u64,
}

#[cfg(target_os = "linux")]
impl Device {
    /// Get a `dev_t` value for this device.
    #[rustfmt::skip]
    pub fn to_dev_t(&self) -> u64 {
        // see bits/sysmacros.h
        ((self.major & 0x0000_0fff) << 8) |
        ((self.major & 0xffff_f000) << 32) |
         (self.minor & 0x0000_00ff) |
        ((self.minor & 0xffff_ff00) << 12)
    }

    /// Get a `Device` from a `dev_t` value.
    #[rustfmt::skip]
    pub fn from_dev_t(dev: u64) -> Self {
        // see to_dev_t
        Self {
            major: (dev >>  8) & 0x0000_0fff |
                   (dev >> 32) & 0xffff_f000,
            minor:  dev        & 0x0000_00ff |
                   (dev >> 12) & 0xffff_ff00,
        }
    }
}

#[cfg(all(test, target_os = "linux"))]
#[test]
fn test_linux_devices() {
    let c_dev = unsafe { ::libc::makedev(0xabcd_1234, 0xdcba_5678) };
    let dev = Device::from_dev_t(c_dev);
    assert_eq!(dev.to_dev_t(), c_dev);
}

#[derive(Clone, Debug)]
#[repr(C)]
pub struct FCaps {
    pub data: Vec<u8>,
}

#[derive(Clone, Copy, Debug, Endian)]
#[repr(C)]
pub struct QuotaProjectId {
    pub projid: u64,
}

#[derive(Clone, Debug, Endian)]
#[repr(C)]
pub struct GoodbyeItem {
    /// SipHash24 of the directory item name. The last GOODBYE item uses the special hash value
    /// `PXAR_GOODBYE_TAIL_MARKER`.
    pub hash: u64,

    /// The offset from the start of the GOODBYE object to the start of the matching directory item
    /// (point to a FILENAME). The last GOODBYE item points to the start of the matching ENTRY
    /// object.
    pub offset: u64,

    /// The overall size of the directory item. This includes the FILENAME header. In other words,
    /// `goodbye_start - offset + size` points to the end of the directory.
    ///
    /// The last GOODBYE item repeats the size of the GOODBYE item.
    pub size: u64,
}

impl GoodbyeItem {
    pub fn new(name: &[u8], offset: u64, size: u64) -> Self {
        let hash = hash_filename(name);
        Self { hash, offset, size }
    }
}

pub fn hash_filename(name: &[u8]) -> u64 {
    use std::hash::Hasher;
    let mut hasher = SipHasher24::new_with_keys(0x8574442b0f1d84b3, 0x2736ed30d1c22ec1);
    hasher.write(name);
    hasher.finish()
}

pub fn path_is_legal_component(path: &Path) -> bool {
    let mut components = path.components();
    match components.next() {
        Some(std::path::Component::Normal(_)) => (),
        _ => return false,
    }
    components.next().is_none()
}

pub fn check_file_name(path: &Path) -> io::Result<()> {
    if !path_is_legal_component(path) {
        io_bail!("invalid file name in archive: {:?}", path);
    } else {
        Ok(())
    }
}
Commit	Line	Data
6cd4f635 WB	1	//! pxar binary format definition
	2	//!
	3	//! Please note the all values are stored in little endian ordering.
	4	//!
	5	//! The Archive contains a list of items. Each item starts with a `Header`, followed by the
	6	//! item data.
	7
	8	use std::cmp::Ordering;
2c442007	9	use std::ffi::{CStr, OsStr};
6cd4f635 WB	10	use std::io;
6cd4f635 WB	11	use std::mem::size_of;
54912ae6	12	use std::os::unix::ffi::OsStrExt;
6cd4f635 WB	13	use std::path::Path;
	14
	15	use endian_trait::Endian;
	16	use siphasher::sip::SipHasher24;
	17
	18	pub mod acl;
	19
70acf637 WB	20	/// While these constants correspond to `libc::S_` constants, we need these to be fixed for the
	21	/// format itself, so we redefine them here.
	22	///
	23	/// Additionally this gets rid of a bunch of casts between u32 and u64.
	24	///
	25	/// You can usually find the values for these in `/usr/include/linux/stat.h`.
	26	#[rustfmt::skip]
	27	pub mod mode {
	28	pub const IFMT : u64 = 0o0170000;
	29
	30	pub const IFSOCK : u64 = 0o0140000;
	31	pub const IFLNK : u64 = 0o0120000;
	32	pub const IFREG : u64 = 0o0100000;
	33	pub const IFBLK : u64 = 0o0060000;
	34	pub const IFDIR : u64 = 0o0040000;
	35	pub const IFCHR : u64 = 0o0020000;
	36	pub const IFIFO : u64 = 0o0010000;
a13a2f74	37
70acf637 WB	38	pub const ISUID : u64 = 0o0004000;
	39	pub const ISGID : u64 = 0o0002000;
	40	pub const ISVTX : u64 = 0o0001000;
	41	}
	42
6cd4f635 WB	43	pub const PXAR_ENTRY: u64 = 0x1396fabcea5bbb51;
	44	pub const PXAR_FILENAME: u64 = 0x6dbb6ebcb3161f0b;
	45	pub const PXAR_SYMLINK: u64 = 0x664a6fb6830e0d6c;
	46	pub const PXAR_DEVICE: u64 = 0xac3dace369dfe643;
	47	pub const PXAR_XATTR: u64 = 0xb8157091f80bc486;
	48	pub const PXAR_ACL_USER: u64 = 0x297dc88b2ef12faf;
	49	pub const PXAR_ACL_GROUP: u64 = 0x36f2acb56cb3dd0b;
	50	pub const PXAR_ACL_GROUP_OBJ: u64 = 0x23047110441f38f3;
	51	pub const PXAR_ACL_DEFAULT: u64 = 0xfe3eeda6823c8cd0;
	52	pub const PXAR_ACL_DEFAULT_USER: u64 = 0xbdf03df9bd010a91;
	53	pub const PXAR_ACL_DEFAULT_GROUP: u64 = 0xa0cb1168782d1f51;
	54	pub const PXAR_FCAPS: u64 = 0xf7267db0afed0629;
	55	pub const PXAR_QUOTA_PROJID: u64 = 0x161baf2d8772a72b;
	56
	57	/// Marks item as hardlink
	58	/// compute_goodbye_hash(b"__PROXMOX_FORMAT_HARDLINK__");
	59	pub const PXAR_HARDLINK: u64 = 0x2c5e06f634f65b86;
	60	/// Marks the beginnig of the payload (actual content) of regular files
	61	pub const PXAR_PAYLOAD: u64 = 0x8b9e1d93d6dcffc9;
	62	/// Marks item as entry of goodbye table
	63	pub const PXAR_GOODBYE: u64 = 0xdfd35c5e8327c403;
	64	/// The end marker used in the GOODBYE object
	65	pub const PXAR_GOODBYE_TAIL_MARKER: u64 = 0x57446fa533702943;
	66
	67	#[derive(Debug, Endian)]
	68	#[repr(C)]
	69	pub struct Header {
	70	/// The item type (see `PXAR_` constants).
	71	pub htype: u64,
	72	/// The size of the item, including the size of `Header`.
	73	full_size: u64,
	74	}
	75
	76	impl Header {
70acf637 WB	77	#[inline]
	78	pub fn with_full_size(htype: u64, full_size: u64) -> Self {
	79	Self { htype, full_size }
	80	}
	81
	82	#[inline]
	83	pub fn with_content_size(htype: u64, content_size: u64) -> Self {
	84	Self::with_full_size(htype, content_size + size_of::<Header>() as u64)
	85	}
	86
6cd4f635 WB	87	#[inline]
	88	pub fn full_size(&self) -> u64 {
	89	self.full_size
	90	}
	91
	92	#[inline]
	93	pub fn content_size(&self) -> u64 {
	94	self.full_size() - (size_of::<Self>() as u64)
	95	}
	96	}
	97
	98	#[derive(Clone, Debug, Default, Endian)]
	99	#[repr(C)]
	100	pub struct Entry {
	101	pub mode: u64,
	102	pub flags: u64,
	103	pub uid: u32,
	104	pub gid: u32,
	105	pub mtime: u64,
	106	}
	107
70acf637 WB	108	/// Builder pattern methods.
	109	impl Entry {
	110	pub const fn mode(self, mode: u64) -> Self {
	111	Self { mode, ..self }
	112	}
	113
	114	pub const fn flags(self, flags: u64) -> Self {
	115	Self { flags, ..self }
	116	}
	117
	118	pub const fn uid(self, uid: u32) -> Self {
	119	Self { uid, ..self }
	120	}
	121
	122	pub const fn gid(self, gid: u32) -> Self {
	123	Self { gid, ..self }
	124	}
	125
	126	pub const fn mtime(self, mtime: u64) -> Self {
	127	Self { mtime, ..self }
	128	}
	129
	130	pub const fn set_dir(self) -> Self {
	131	let mode = self.mode;
	132	self.mode((mode & !mode::IFMT) \| mode::IFDIR)
	133	}
	134
	135	pub const fn set_regular_file(self) -> Self {
	136	let mode = self.mode;
	137	self.mode((mode & !mode::IFMT) \| mode::IFREG)
	138	}
	139
	140	pub const fn set_symlink(self) -> Self {
	141	let mode = self.mode;
	142	self.mode((mode & !mode::IFMT) \| mode::IFLNK)
	143	}
	144
	145	pub const fn set_blockdev(self) -> Self {
	146	let mode = self.mode;
	147	self.mode((mode & !mode::IFMT) \| mode::IFBLK)
	148	}
	149
	150	pub const fn set_chardev(self) -> Self {
	151	let mode = self.mode;
	152	self.mode((mode & !mode::IFMT) \| mode::IFCHR)
	153	}
	154
	155	pub const fn set_fifo(self) -> Self {
	156	let mode = self.mode;
	157	self.mode((mode & !mode::IFMT) \| mode::IFIFO)
	158	}
	159	}
	160
6da548dd WB	161	/// Convenience accessor methods.
	162	impl Entry {
	163	/// Get the mtime as duration since the epoch.
	164	pub fn mtime_as_duration(&self) -> std::time::Duration {
	165	std::time::Duration::from_nanos(self.mtime)
	166	}
8617cae3 WB	167
	168	/// Get the file type portion of the mode bitfield.
	169	pub fn get_file_bits(&self) -> u64 {
	170	self.mode & mode::IFMT
	171	}
	172
	173	/// Get the permission portion of the mode bitfield.
	174	pub fn get_permission_bits(&self) -> u64 {
	175	self.mode & !mode::IFMT
	176	}
6da548dd WB	177	}
6da548dd WB	178
70acf637 WB	179	/// Convenience methods.
70acf637 WB	180	impl Entry {
21d66e10 WB	181	/// Get the file type (`mode & mode::IFMT`).
	182	pub fn file_type(&self) -> u64 {
	183	self.mode & mode::IFMT
	184	}
	185
	186	/// Get the file mode bits (`mode & !mode::IFMT`).
	187	pub fn file_mode(&self) -> u64 {
	188	self.mode & !mode::IFMT
	189	}
	190
70acf637 WB	191	/// Check whether this is a directory.
	192	pub fn is_dir(&self) -> bool {
	193	(self.mode & mode::IFMT) == mode::IFDIR
	194	}
	195
	196	/// Check whether this is a symbolic link.
	197	pub fn is_symlink(&self) -> bool {
	198	(self.mode & mode::IFMT) == mode::IFLNK
	199	}
	200
	201	/// Check whether this is a device node.
	202	pub fn is_device(&self) -> bool {
	203	let fmt = self.mode & mode::IFMT;
	204	fmt == mode::IFCHR \|\| fmt == mode::IFBLK
	205	}
	206
da286c28 WB	207	/// Check whether this is a block device node.
	208	pub fn is_blockdev(&self) -> bool {
	209	let fmt = self.mode & mode::IFMT;
	210	fmt == mode::IFBLK
	211	}
	212
	213	/// Check whether this is a character device node.
	214	pub fn is_chardev(&self) -> bool {
	215	let fmt = self.mode & mode::IFMT;
	216	fmt == mode::IFCHR
	217	}
	218
70acf637 WB	219	/// Check whether this is a regular file.
	220	pub fn is_regular_file(&self) -> bool {
	221	(self.mode & mode::IFMT) == mode::IFREG
	222	}
2287d8b2 WB	223
	224	/// Check whether this is a named pipe (FIFO).
	225	pub fn is_fifo(&self) -> bool {
	226	(self.mode & mode::IFMT) == mode::IFIFO
	227	}
	228
	229	/// Check whether this is a named socket.
	230	pub fn is_socket(&self) -> bool {
	231	(self.mode & mode::IFMT) == mode::IFSOCK
	232	}
70acf637 WB	233	}
	234
	235	impl From<&std::fs::Metadata> for Entry {
	236	fn from(meta: &std::fs::Metadata) -> Entry {
	237	#[cfg(unix)]
	238	use std::os::unix::fs::MetadataExt;
	239
	240	let this = Entry::default();
	241
	242	#[cfg(unix)]
	243	let this = this
	244	.uid(meta.uid())
	245	.gid(meta.gid())
	246	.mode(meta.mode() as u64)
	247	.mtime(meta.mtime() as u64);
	248
	249	let file_type = meta.file_type();
	250	let mode = this.mode;
	251	let this = if file_type.is_dir() {
	252	this.mode(mode \| mode::IFDIR)
	253	} else if file_type.is_symlink() {
	254	this.mode(mode \| mode::IFLNK)
	255	} else {
	256	this.mode(mode \| mode::IFREG)
	257	};
	258
	259	this
	260	}
	261	}
	262
6cd4f635 WB	263	#[derive(Clone, Debug)]
	264	pub struct Filename {
	265	pub name: Vec<u8>,
	266	}
	267
	268	#[derive(Clone, Debug)]
	269	pub struct Symlink {
	270	pub data: Vec<u8>,
	271	}
	272
7b389f88 WB	273	impl Symlink {
	274	pub fn as_os_str(&self) -> &OsStr {
	275	self.as_ref()
	276	}
	277	}
	278
353bbf73 WB	279	impl AsRef<[u8]> for Symlink {
	280	fn as_ref(&self) -> &[u8] {
	281	&self.data
	282	}
	283	}
	284
54912ae6 WB	285	impl AsRef<OsStr> for Symlink {
54912ae6 WB	286	fn as_ref(&self) -> &OsStr {
353bbf73	287	OsStr::from_bytes(&self.data[..self.data.len().max(1) - 1])
54912ae6 WB	288	}
	289	}
	290
6cd4f635 WB	291	#[derive(Clone, Debug)]
6cd4f635 WB	292	pub struct Hardlink {
b0752929	293	pub offset: u64,
6cd4f635 WB	294	pub data: Vec<u8>,
	295	}
	296
7b389f88 WB	297	impl Hardlink {
	298	pub fn as_os_str(&self) -> &OsStr {
	299	self.as_ref()
	300	}
	301	}
	302
353bbf73 WB	303	impl AsRef<[u8]> for Hardlink {
	304	fn as_ref(&self) -> &[u8] {
	305	&self.data
	306	}
	307	}
	308
54912ae6 WB	309	impl AsRef<OsStr> for Hardlink {
54912ae6 WB	310	fn as_ref(&self) -> &OsStr {
353bbf73	311	OsStr::from_bytes(&self.data[..self.data.len().max(1) - 1])
54912ae6 WB	312	}
	313	}
	314
6cd4f635 WB	315	#[derive(Clone, Debug, Eq)]
	316	#[repr(C)]
	317	pub struct XAttr {
	318	pub(crate) data: Vec<u8>,
	319	pub(crate) name_len: usize,
	320	}
	321
	322	impl XAttr {
	323	pub fn new<N: AsRef<[u8]>, V: AsRef<[u8]>>(name: N, value: V) -> Self {
	324	let name = name.as_ref();
	325	let value = value.as_ref();
	326	let mut data = Vec::with_capacity(name.len() + value.len() + 1);
	327	data.extend(name);
	328	data.push(0);
	329	data.extend(value);
	330	Self {
	331	data,
	332	name_len: name.len(),
	333	}
	334	}
	335
2c442007	336	pub fn name(&self) -> &CStr {
2fd112ac	337	unsafe { CStr::from_bytes_with_nul_unchecked(&self.data[..self.name_len + 1]) }
6cd4f635 WB	338	}
	339
	340	pub fn value(&self) -> &[u8] {
	341	&self.data[(self.name_len + 1)..]
	342	}
	343	}
	344
	345	impl Ord for XAttr {
	346	fn cmp(&self, other: &XAttr) -> Ordering {
	347	self.name().cmp(&other.name())
	348	}
	349	}
	350
	351	impl PartialOrd for XAttr {
	352	fn partial_cmp(&self, other: &XAttr) -> Option<Ordering> {
	353	Some(self.cmp(other))
	354	}
	355	}
	356
	357	impl PartialEq for XAttr {
	358	fn eq(&self, other: &XAttr) -> bool {
	359	self.name() == other.name()
	360	}
	361	}
	362
	363	#[derive(Clone, Debug, Endian)]
	364	#[repr(C)]
	365	pub struct Device {
	366	pub major: u64,
	367	pub minor: u64,
	368	}
	369
9cda3431 WB	370	#[cfg(target_os = "linux")]
	371	impl Device {
	372	/// Get a `dev_t` value for this device.
	373	#[rustfmt::skip]
	374	pub fn to_dev_t(&self) -> u64 {
	375	// see bits/sysmacros.h
	376	((self.major & 0x0000_0fff) << 8) \|
	377	((self.major & 0xffff_f000) << 32) \|
	378	(self.minor & 0x0000_00ff) \|
	379	((self.minor & 0xffff_ff00) << 12)
	380	}
2fd112ac WB	381
	382	/// Get a `Device` from a `dev_t` value.
	383	#[rustfmt::skip]
	384	pub fn from_dev_t(dev: u64) -> Self {
	385	// see to_dev_t
	386	Self {
	387	major: (dev >> 8) & 0x0000_0fff \|
	388	(dev >> 32) & 0xffff_f000,
	389	minor: dev & 0x0000_00ff \|
	390	(dev >> 12) & 0xffff_ff00,
	391	}
	392	}
	393	}
	394
	395	#[cfg(all(test, target_os = "linux"))]
	396	#[test]
	397	fn test_linux_devices() {
	398	let c_dev = unsafe { ::libc::makedev(0xabcd_1234, 0xdcba_5678) };
	399	let dev = Device::from_dev_t(c_dev);
	400	assert_eq!(dev.to_dev_t(), c_dev);
9cda3431 WB	401	}
9cda3431 WB	402
6cd4f635 WB	403	#[derive(Clone, Debug)]
	404	#[repr(C)]
	405	pub struct FCaps {
	406	pub data: Vec<u8>,
	407	}
	408
3680d0ee	409	#[derive(Clone, Copy, Debug, Endian)]
6cd4f635 WB	410	#[repr(C)]
	411	pub struct QuotaProjectId {
	412	pub projid: u64,
	413	}
	414
70acf637	415	#[derive(Clone, Debug, Endian)]
6cd4f635 WB	416	#[repr(C)]
	417	pub struct GoodbyeItem {
	418	/// SipHash24 of the directory item name. The last GOODBYE item uses the special hash value
	419	/// `PXAR_GOODBYE_TAIL_MARKER`.
	420	pub hash: u64,
	421
	422	/// The offset from the start of the GOODBYE object to the start of the matching directory item
	423	/// (point to a FILENAME). The last GOODBYE item points to the start of the matching ENTRY
	424	/// object.
	425	pub offset: u64,
	426
	427	/// The overall size of the directory item. This includes the FILENAME header. In other words,
	428	/// `goodbye_start - offset + size` points to the end of the directory.
	429	///
	430	/// The last GOODBYE item repeats the size of the GOODBYE item.
	431	pub size: u64,
	432	}
	433
	434	impl GoodbyeItem {
	435	pub fn new(name: &[u8], offset: u64, size: u64) -> Self {
	436	let hash = hash_filename(name);
	437	Self { hash, offset, size }
	438	}
	439	}
	440
	441	pub fn hash_filename(name: &[u8]) -> u64 {
	442	use std::hash::Hasher;
	443	let mut hasher = SipHasher24::new_with_keys(0x8574442b0f1d84b3, 0x2736ed30d1c22ec1);
	444	hasher.write(name);
	445	hasher.finish()
	446	}
	447
6cd4f635 WB	448	pub fn path_is_legal_component(path: &Path) -> bool {
	449	let mut components = path.components();
	450	match components.next() {
	451	Some(std::path::Component::Normal(_)) => (),
	452	_ => return false,
	453	}
	454	components.next().is_none()
	455	}
	456
	457	pub fn check_file_name(path: &Path) -> io::Result<()> {
	458	if !path_is_legal_component(path) {
	459	io_bail!("invalid file name in archive: {:?}", path);
	460	} else {
	461	Ok(())
	462	}
	463	}