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use nom::{le_u32};
use blocks;
use util;
#[derive(Debug)]
pub enum Block<'a> {
SectionHeader(blocks::SectionHeader<'a>),
EnhancedPacket(blocks::EnhancedPacket<'a>),
InterfaceDescription(blocks::InterfaceDescription<'a>),
}
#[derive(Debug)]
pub struct RawBlock<'a> {
pub ty: u32,
pub block_length: u32,
pub body: &'a [u8],
pub check_length: u32,
}
impl<'a> RawBlock<'a> {
pub fn parse(self) -> Block<'a> {
match self.ty {
blocks::section_header::TY => Block::SectionHeader(blocks::section_header::parse(self)),
blocks::enhanced_packet::TY => Block::EnhancedPacket(blocks::enhanced_packet::parse(self)),
blocks::interface_description::TY => Block::InterfaceDescription(blocks::interface_description::parse(self)),
_ => panic!("Unknown block type {:x}", self.ty),
}
}
}
named!(pub parse_block< &[u8],RawBlock >,
chain!(
ty: le_u32 ~
block_length: le_u32 ~
body: take!((block_length - 12) as usize) ~
take!(util::pad_to_32bits((block_length - 12) as usize)) ~
check_length: le_u32 ,
||{ RawBlock {
ty: ty,
block_length: block_length,
body: body,
check_length: check_length
} }
)
);
named!(pub parse_blocks< &[u8],Vec<RawBlock> >,
many1!(parse_block)
);
#[cfg(test)]
use nom::IResult;
#[test]
fn test_parse_block() {
let input = b"\n\r\r\n\x1c\x00\x00\x00M<+\x1a\x01\x00\x00\x00\xff\xff\xff\xff\xff\xff\xff\xff\x1c\x00\x00\x00";
match parse_block(input) {
IResult::Done(left, RawBlock { ty, block_length, body, check_length }) => {
assert_eq!(left, b"");
assert_eq!(ty, 0x0A0D0D0A);
assert_eq!(block_length, 28);
assert_eq!(body, b"M<+\x1a\x01\x00\x00\x00\xff\xff\xff\xff\xff\xff\xff\xff");
assert_eq!(check_length, 28);
},
_ => {
assert_eq!(1, 2);
},
}
}
#[test]
fn test_parse_blocks() {
let input = b"\n\r\r\n\x1c\x00\x00\x00M<+\x1a\x01\x00\x00\x00\xff\xff\xff\xff\xff\xff\xff\xff\x1c\x00\x00\x00\
\n\r\r\n\x1c\x00\x00\x00M<+\x1a\x01\x00\x00\x00\xff\xff\xff\xff\xff\xff\xff\xff\x1c\x00\x00\x00";
match parse_blocks(input) {
IResult::Done(left, blocks) => {
assert_eq!(blocks.len(), 2);
for i in blocks {
let RawBlock { ty, block_length, body, check_length } = i;
assert_eq!(left, b"");
assert_eq!(ty, 0x0A0D0D0A);
assert_eq!(block_length, 28);
assert_eq!(body, b"M<+\x1a\x01\x00\x00\x00\xff\xff\xff\xff\xff\xff\xff\xff");
assert_eq!(check_length, 28);
}
},
_ => {
assert_eq!(1, 2);
},
}
}
#[test]
fn test_parse_weird_length_block() {
let input = b"\n\r\r\n\x1b\x00\x00\x00<+\x1a\x01\x00\x00\x00\xff\xff\xff\xff\xff\xff\xff\xff\x00\x1b\x00\x00\x00";
match parse_block(input) {
IResult::Done(left, RawBlock { ty, block_length, body, check_length }) => {
assert_eq!(left, b"");
assert_eq!(ty, 0x0A0D0D0A);
assert_eq!(27, block_length);
assert_eq!(body.len() + 12, block_length as usize);
assert_eq!(body, b"<+\x1a\x01\x00\x00\x00\xff\xff\xff\xff\xff\xff\xff\xff");
assert_eq!(body.len() + 12, check_length as usize);
},
_ => {
unreachable!("Couldn't parse the block");
},
}
}
#[test]
fn test_multiple_options() {
let input = b"\x0a\x0d\x0d\x0a\x40\x00\x00\x00\x4d\x3c\x2b\x1a\x01\x00\x00\x00\
\xff\xff\xff\xff\xff\xff\xff\xff\x03\x00\x0b\x00\x57\x69\x6e\x64\
\x6f\x77\x73\x20\x58\x50\x00\x00\x04\x00\x0c\x00\x54\x65\x73\x74\
\x30\x30\x34\x2e\x65\x78\x65\x00\x00\x00\x00\x00\x40\x00\x00\x00";
match parse_block(input) {
IResult::Done(left, block) => {
assert_eq!(left, b"");
if let Block::SectionHeader(blk) = block.parse() {
if let Some(opts) = blk.options {
assert_eq!(opts.options.len(), 3);
let o = &opts.options[0];
assert_eq!(o.code, 0x03);
assert_eq!(o.length, 0x0b);
assert_eq!(&o.value[..], b"Windows XP\x00");
let o = &opts.options[1];
assert_eq!(o.code, 0x04);
assert_eq!(o.length, 0x0c);
assert_eq!(&o.value[..], b"Test004.exe\x00");
let o = &opts.options[2];
assert_eq!(o.code, 0x00);
assert_eq!(o.length, 0x00);
assert_eq!(&o.value[..], b"");
} else {
unreachable!();
}
} else {
unreachable!();
}
},
_ => {
panic!("Hit a codepath we shouldn't have");
},
}
}