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Diffstat (limited to 'vendor/gimli/src/read/aranges.rs')
| -rw-r--r-- | vendor/gimli/src/read/aranges.rs | 660 |
1 files changed, 660 insertions, 0 deletions
diff --git a/vendor/gimli/src/read/aranges.rs b/vendor/gimli/src/read/aranges.rs new file mode 100644 index 0000000..83159b6 --- /dev/null +++ b/vendor/gimli/src/read/aranges.rs @@ -0,0 +1,660 @@ +use crate::common::{DebugArangesOffset, DebugInfoOffset, Encoding, SectionId}; +use crate::endianity::Endianity; +use crate::read::{EndianSlice, Error, Range, Reader, ReaderOffset, Result, Section}; + +/// The `DebugAranges` struct represents the DWARF address range information +/// found in the `.debug_aranges` section. +#[derive(Debug, Default, Clone, Copy)] +pub struct DebugAranges<R> { + section: R, +} + +impl<'input, Endian> DebugAranges<EndianSlice<'input, Endian>> +where + Endian: Endianity, +{ + /// Construct a new `DebugAranges` instance from the data in the `.debug_aranges` + /// section. + /// + /// It is the caller's responsibility to read the `.debug_aranges` section and + /// present it as a `&[u8]` slice. That means using some ELF loader on + /// Linux, a Mach-O loader on macOS, etc. + /// + /// ``` + /// use gimli::{DebugAranges, LittleEndian}; + /// + /// # let buf = []; + /// # let read_debug_aranges_section = || &buf; + /// let debug_aranges = + /// DebugAranges::new(read_debug_aranges_section(), LittleEndian); + /// ``` + pub fn new(section: &'input [u8], endian: Endian) -> Self { + DebugAranges { + section: EndianSlice::new(section, endian), + } + } +} + +impl<R: Reader> DebugAranges<R> { + /// Iterate the sets of entries in the `.debug_aranges` section. + /// + /// Each set of entries belongs to a single unit. + pub fn headers(&self) -> ArangeHeaderIter<R> { + ArangeHeaderIter { + input: self.section.clone(), + offset: DebugArangesOffset(R::Offset::from_u8(0)), + } + } + + /// Get the header at the given offset. + pub fn header(&self, offset: DebugArangesOffset<R::Offset>) -> Result<ArangeHeader<R>> { + let mut input = self.section.clone(); + input.skip(offset.0)?; + ArangeHeader::parse(&mut input, offset) + } +} + +impl<T> DebugAranges<T> { + /// Create a `DebugAranges` section that references the data in `self`. + /// + /// This is useful when `R` implements `Reader` but `T` does not. + /// + /// ## Example Usage + /// + /// ```rust,no_run + /// # let load_section = || unimplemented!(); + /// // Read the DWARF section into a `Vec` with whatever object loader you're using. + /// let owned_section: gimli::DebugAranges<Vec<u8>> = load_section(); + /// // Create a reference to the DWARF section. + /// let section = owned_section.borrow(|section| { + /// gimli::EndianSlice::new(§ion, gimli::LittleEndian) + /// }); + /// ``` + pub fn borrow<'a, F, R>(&'a self, mut borrow: F) -> DebugAranges<R> + where + F: FnMut(&'a T) -> R, + { + borrow(&self.section).into() + } +} + +impl<R> Section<R> for DebugAranges<R> { + fn id() -> SectionId { + SectionId::DebugAranges + } + + fn reader(&self) -> &R { + &self.section + } +} + +impl<R> From<R> for DebugAranges<R> { + fn from(section: R) -> Self { + DebugAranges { section } + } +} + +/// An iterator over the headers of a `.debug_aranges` section. +#[derive(Clone, Debug)] +pub struct ArangeHeaderIter<R: Reader> { + input: R, + offset: DebugArangesOffset<R::Offset>, +} + +impl<R: Reader> ArangeHeaderIter<R> { + /// Advance the iterator to the next header. + pub fn next(&mut self) -> Result<Option<ArangeHeader<R>>> { + if self.input.is_empty() { + return Ok(None); + } + + let len = self.input.len(); + match ArangeHeader::parse(&mut self.input, self.offset) { + Ok(header) => { + self.offset.0 += len - self.input.len(); + Ok(Some(header)) + } + Err(e) => { + self.input.empty(); + Err(e) + } + } + } +} + +#[cfg(feature = "fallible-iterator")] +impl<R: Reader> fallible_iterator::FallibleIterator for ArangeHeaderIter<R> { + type Item = ArangeHeader<R>; + type Error = Error; + + fn next(&mut self) -> ::core::result::Result<Option<Self::Item>, Self::Error> { + ArangeHeaderIter::next(self) + } +} + +/// A header for a set of entries in the `.debug_arange` section. +/// +/// These entries all belong to a single unit. +#[derive(Debug, Clone, PartialEq, Eq)] +pub struct ArangeHeader<R, Offset = <R as Reader>::Offset> +where + R: Reader<Offset = Offset>, + Offset: ReaderOffset, +{ + offset: DebugArangesOffset<Offset>, + encoding: Encoding, + length: Offset, + debug_info_offset: DebugInfoOffset<Offset>, + segment_size: u8, + entries: R, +} + +impl<R, Offset> ArangeHeader<R, Offset> +where + R: Reader<Offset = Offset>, + Offset: ReaderOffset, +{ + fn parse(input: &mut R, offset: DebugArangesOffset<Offset>) -> Result<Self> { + let (length, format) = input.read_initial_length()?; + let mut rest = input.split(length)?; + + // Check the version. The DWARF 5 spec says that this is always 2, but version 3 + // has been observed in the wild, potentially due to a bug; see + // https://github.com/gimli-rs/gimli/issues/559 for more information. + // lldb allows versions 2 through 5, possibly by mistake. + let version = rest.read_u16()?; + if version != 2 && version != 3 { + return Err(Error::UnknownVersion(u64::from(version))); + } + + let debug_info_offset = rest.read_offset(format).map(DebugInfoOffset)?; + let address_size = rest.read_u8()?; + let segment_size = rest.read_u8()?; + + // unit_length + version + offset + address_size + segment_size + let header_length = format.initial_length_size() + 2 + format.word_size() + 1 + 1; + + // The first tuple following the header in each set begins at an offset that is + // a multiple of the size of a single tuple (that is, the size of a segment selector + // plus twice the size of an address). + let tuple_length = address_size + .checked_mul(2) + .and_then(|x| x.checked_add(segment_size)) + .ok_or(Error::InvalidAddressRange)?; + if tuple_length == 0 { + return Err(Error::InvalidAddressRange)?; + } + let padding = if header_length % tuple_length == 0 { + 0 + } else { + tuple_length - header_length % tuple_length + }; + rest.skip(R::Offset::from_u8(padding))?; + + let encoding = Encoding { + format, + version, + address_size, + // TODO: segment_size + }; + Ok(ArangeHeader { + offset, + encoding, + length, + debug_info_offset, + segment_size, + entries: rest, + }) + } + + /// Return the offset of this header within the `.debug_aranges` section. + #[inline] + pub fn offset(&self) -> DebugArangesOffset<Offset> { + self.offset + } + + /// Return the length of this set of entries, including the header. + #[inline] + pub fn length(&self) -> Offset { + self.length + } + + /// Return the encoding parameters for this set of entries. + #[inline] + pub fn encoding(&self) -> Encoding { + self.encoding + } + + /// Return the segment size for this set of entries. + #[inline] + pub fn segment_size(&self) -> u8 { + self.segment_size + } + + /// Return the offset into the .debug_info section for this set of arange entries. + #[inline] + pub fn debug_info_offset(&self) -> DebugInfoOffset<Offset> { + self.debug_info_offset + } + + /// Return the arange entries in this set. + #[inline] + pub fn entries(&self) -> ArangeEntryIter<R> { + ArangeEntryIter { + input: self.entries.clone(), + encoding: self.encoding, + segment_size: self.segment_size, + } + } +} + +/// An iterator over the aranges from a `.debug_aranges` section. +/// +/// Can be [used with +/// `FallibleIterator`](./index.html#using-with-fallibleiterator). +#[derive(Debug, Clone)] +pub struct ArangeEntryIter<R: Reader> { + input: R, + encoding: Encoding, + segment_size: u8, +} + +impl<R: Reader> ArangeEntryIter<R> { + /// Advance the iterator and return the next arange. + /// + /// Returns the newly parsed arange as `Ok(Some(arange))`. Returns `Ok(None)` + /// when iteration is complete and all aranges have already been parsed and + /// yielded. If an error occurs while parsing the next arange, then this error + /// is returned as `Err(e)`, and all subsequent calls return `Ok(None)`. + pub fn next(&mut self) -> Result<Option<ArangeEntry>> { + if self.input.is_empty() { + return Ok(None); + } + + match ArangeEntry::parse(&mut self.input, self.encoding, self.segment_size) { + Ok(Some(entry)) => Ok(Some(entry)), + Ok(None) => { + self.input.empty(); + Ok(None) + } + Err(e) => { + self.input.empty(); + Err(e) + } + } + } +} + +#[cfg(feature = "fallible-iterator")] +impl<R: Reader> fallible_iterator::FallibleIterator for ArangeEntryIter<R> { + type Item = ArangeEntry; + type Error = Error; + + fn next(&mut self) -> ::core::result::Result<Option<Self::Item>, Self::Error> { + ArangeEntryIter::next(self) + } +} + +/// A single parsed arange. +#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord)] +pub struct ArangeEntry { + segment: Option<u64>, + address: u64, + length: u64, +} + +impl ArangeEntry { + /// Parse a single arange. Return `None` for the null arange, `Some` for an actual arange. + fn parse<R: Reader>( + input: &mut R, + encoding: Encoding, + segment_size: u8, + ) -> Result<Option<Self>> { + let address_size = encoding.address_size; + + let tuple_length = R::Offset::from_u8(2 * address_size + segment_size); + if tuple_length > input.len() { + input.empty(); + return Ok(None); + } + + let segment = if segment_size != 0 { + input.read_address(segment_size)? + } else { + 0 + }; + let address = input.read_address(address_size)?; + let length = input.read_address(address_size)?; + + match (segment, address, length) { + // This is meant to be a null terminator, but in practice it can occur + // before the end, possibly due to a linker omitting a function and + // leaving an unrelocated entry. + (0, 0, 0) => Self::parse(input, encoding, segment_size), + _ => Ok(Some(ArangeEntry { + segment: if segment_size != 0 { + Some(segment) + } else { + None + }, + address, + length, + })), + } + } + + /// Return the segment selector of this arange. + #[inline] + pub fn segment(&self) -> Option<u64> { + self.segment + } + + /// Return the beginning address of this arange. + #[inline] + pub fn address(&self) -> u64 { + self.address + } + + /// Return the length of this arange. + #[inline] + pub fn length(&self) -> u64 { + self.length + } + + /// Return the range. + #[inline] + pub fn range(&self) -> Range { + Range { + begin: self.address, + end: self.address.wrapping_add(self.length), + } + } +} + +#[cfg(test)] +mod tests { + use super::*; + use crate::common::{DebugInfoOffset, Format}; + use crate::endianity::LittleEndian; + use crate::read::EndianSlice; + + #[test] + fn test_iterate_headers() { + #[rustfmt::skip] + let buf = [ + // 32-bit length = 28. + 0x1c, 0x00, 0x00, 0x00, + // Version. + 0x02, 0x00, + // Offset. + 0x01, 0x02, 0x03, 0x04, + // Address size. + 0x04, + // Segment size. + 0x00, + // Dummy padding and arange tuples. + 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + + // 32-bit length = 36. + 0x24, 0x00, 0x00, 0x00, + // Version. + 0x02, 0x00, + // Offset. + 0x11, 0x12, 0x13, 0x14, + // Address size. + 0x04, + // Segment size. + 0x00, + // Dummy padding and arange tuples. + 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + ]; + + let debug_aranges = DebugAranges::new(&buf, LittleEndian); + let mut headers = debug_aranges.headers(); + + let header = headers + .next() + .expect("should parse header ok") + .expect("should have a header"); + assert_eq!(header.offset(), DebugArangesOffset(0)); + assert_eq!(header.debug_info_offset(), DebugInfoOffset(0x0403_0201)); + + let header = headers + .next() + .expect("should parse header ok") + .expect("should have a header"); + assert_eq!(header.offset(), DebugArangesOffset(0x20)); + assert_eq!(header.debug_info_offset(), DebugInfoOffset(0x1413_1211)); + } + + #[test] + fn test_parse_header_ok() { + #[rustfmt::skip] + let buf = [ + // 32-bit length = 32. + 0x20, 0x00, 0x00, 0x00, + // Version. + 0x02, 0x00, + // Offset. + 0x01, 0x02, 0x03, 0x04, + // Address size. + 0x08, + // Segment size. + 0x04, + // Length to here = 12, tuple length = 20. + // Padding to tuple length multiple = 4. + 0x10, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, + + // Dummy arange tuple data. + 0x20, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, + + // Dummy next arange. + 0x30, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, + ]; + + let rest = &mut EndianSlice::new(&buf, LittleEndian); + + let header = + ArangeHeader::parse(rest, DebugArangesOffset(0x10)).expect("should parse header ok"); + + assert_eq!( + *rest, + EndianSlice::new(&buf[buf.len() - 16..], LittleEndian) + ); + assert_eq!( + header, + ArangeHeader { + offset: DebugArangesOffset(0x10), + encoding: Encoding { + format: Format::Dwarf32, + version: 2, + address_size: 8, + }, + length: 0x20, + debug_info_offset: DebugInfoOffset(0x0403_0201), + segment_size: 4, + entries: EndianSlice::new(&buf[buf.len() - 32..buf.len() - 16], LittleEndian), + } + ); + } + + #[test] + fn test_parse_header_overflow_error() { + #[rustfmt::skip] + let buf = [ + // 32-bit length = 32. + 0x20, 0x00, 0x00, 0x00, + // Version. + 0x02, 0x00, + // Offset. + 0x01, 0x02, 0x03, 0x04, + // Address size. + 0xff, + // Segment size. + 0xff, + // Length to here = 12, tuple length = 20. + // Padding to tuple length multiple = 4. + 0x10, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, + + // Dummy arange tuple data. + 0x20, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, + + // Dummy next arange. + 0x30, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, + ]; + + let rest = &mut EndianSlice::new(&buf, LittleEndian); + + let error = ArangeHeader::parse(rest, DebugArangesOffset(0x10)) + .expect_err("should fail to parse header"); + assert_eq!(error, Error::InvalidAddressRange); + } + + #[test] + fn test_parse_header_div_by_zero_error() { + #[rustfmt::skip] + let buf = [ + // 32-bit length = 32. + 0x20, 0x00, 0x00, 0x00, + // Version. + 0x02, 0x00, + // Offset. + 0x01, 0x02, 0x03, 0x04, + // Address size = 0. Could cause a division by zero if we aren't + // careful. + 0x00, + // Segment size. + 0x00, + // Length to here = 12, tuple length = 20. + // Padding to tuple length multiple = 4. + 0x10, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, + + // Dummy arange tuple data. + 0x20, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, + + // Dummy next arange. + 0x30, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, + ]; + + let rest = &mut EndianSlice::new(&buf, LittleEndian); + + let error = ArangeHeader::parse(rest, DebugArangesOffset(0x10)) + .expect_err("should fail to parse header"); + assert_eq!(error, Error::InvalidAddressRange); + } + + #[test] + fn test_parse_entry_ok() { + let encoding = Encoding { + format: Format::Dwarf32, + version: 2, + address_size: 4, + }; + let segment_size = 0; + let buf = [0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09]; + let rest = &mut EndianSlice::new(&buf, LittleEndian); + let entry = + ArangeEntry::parse(rest, encoding, segment_size).expect("should parse entry ok"); + assert_eq!(*rest, EndianSlice::new(&buf[buf.len() - 1..], LittleEndian)); + assert_eq!( + entry, + Some(ArangeEntry { + segment: None, + address: 0x0403_0201, + length: 0x0807_0605, + }) + ); + } + + #[test] + fn test_parse_entry_segment() { + let encoding = Encoding { + format: Format::Dwarf32, + version: 2, + address_size: 4, + }; + let segment_size = 8; + #[rustfmt::skip] + let buf = [ + // Segment. + 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, + // Address. + 0x01, 0x02, 0x03, 0x04, + // Length. + 0x05, 0x06, 0x07, 0x08, + // Next tuple. + 0x09 + ]; + let rest = &mut EndianSlice::new(&buf, LittleEndian); + let entry = + ArangeEntry::parse(rest, encoding, segment_size).expect("should parse entry ok"); + assert_eq!(*rest, EndianSlice::new(&buf[buf.len() - 1..], LittleEndian)); + assert_eq!( + entry, + Some(ArangeEntry { + segment: Some(0x1817_1615_1413_1211), + address: 0x0403_0201, + length: 0x0807_0605, + }) + ); + } + + #[test] + fn test_parse_entry_zero() { + let encoding = Encoding { + format: Format::Dwarf32, + version: 2, + address_size: 4, + }; + let segment_size = 0; + #[rustfmt::skip] + let buf = [ + // Zero tuple. + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + // Address. + 0x01, 0x02, 0x03, 0x04, + // Length. + 0x05, 0x06, 0x07, 0x08, + // Next tuple. + 0x09 + ]; + let rest = &mut EndianSlice::new(&buf, LittleEndian); + let entry = + ArangeEntry::parse(rest, encoding, segment_size).expect("should parse entry ok"); + assert_eq!(*rest, EndianSlice::new(&buf[buf.len() - 1..], LittleEndian)); + assert_eq!( + entry, + Some(ArangeEntry { + segment: None, + address: 0x0403_0201, + length: 0x0807_0605, + }) + ); + } +} |