/rust/registry/src/index.crates.io-1949cf8c6b5b557f/ipsec-parser-0.7.0/src/esp.rs

Source
use crate::ikev2::IkeV2Header;
use crate::ikev2_parser::parse_ikev2_header;
use nom::bytes::streaming::take;
use nom::combinator::rest;
use nom::number::streaming::be_u32;
use nom::IResult;

/// Encapsulating Security Payload Packet Format
///
/// Defined in [RFC2406](https://tools.ietf.org/html/rfc2406) section 2
#[derive(Debug)]
pub struct ESPHeader<'a> {
    pub spi_index: &'a [u8],
    pub seq: u32,
    pub data: &'a [u8],
}

/// UDP-encapsulated Packet Formats
///
/// Defined in [RFC3948](https://tools.ietf.org/html/rfc3948) section 2
#[derive(Debug)]
pub enum ESPData<'a> {
    ESP(ESPHeader<'a>),
    IKE(IkeV2Header),
}

/// Parse an encapsulated ESP packet
///
/// The type of encapsulated data depends on the first field (`spi_index`): 0 is a forbidden SPI
/// index, and indicates that the header is an IKE header.
/// Any other value indicates an ESP header.
///
/// *Note: input is entirely consumed*
pub fn parse_esp_encapsulated(i: &[u8]) -> IResult<&[u8], ESPData> {
    if be_u32(i)?.1 == 0 {
        parse_ikev2_header(i).map(|x| (x.0, ESPData::IKE(x.1)))
    } else {
        parse_esp_header(i).map(|x| (x.0, ESPData::ESP(x.1)))
    }
}

/// Parse an ESP packet
///
/// The ESP header contains:
///
/// - the SPI index
/// - the sequence number
/// - the payload data (which can be encrypted)
///
/// *Note: input is entirely consumed*
pub fn parse_esp_header(i: &[u8]) -> IResult<&[u8], ESPHeader> {
    let (i, spi_index) = take(4usize)(i)?;
    let (i, seq) = be_u32(i)?;
    let (i, data) = rest(i)?;
    let hdr = ESPHeader {
        spi_index,
        seq,
        data,
    };
    Ok((i, hdr))
}

Coverage Report

Created: 2026-02-14 06:42

Line	Count	Source
1		use crate::ikev2::IkeV2Header;
2		use crate::ikev2_parser::parse_ikev2_header;
3		use nom::bytes::streaming::take;
4		use nom::combinator::rest;
5		use nom::number::streaming::be_u32;
6		use nom::IResult;
7
8		/// Encapsulating Security Payload Packet Format
9		///
10		/// Defined in [RFC2406](https://tools.ietf.org/html/rfc2406) section 2
11		#[derive(Debug)]
12		pub struct ESPHeader<'a> {
13		pub spi_index: &'a [u8],
14		pub seq: u32,
15		pub data: &'a [u8],
16		}
17
18		/// UDP-encapsulated Packet Formats
19		///
20		/// Defined in [RFC3948](https://tools.ietf.org/html/rfc3948) section 2
21		#[derive(Debug)]
22		pub enum ESPData<'a> {
23		ESP(ESPHeader<'a>),
24		IKE(IkeV2Header),
25		}
26
27		/// Parse an encapsulated ESP packet
28		///
29		/// The type of encapsulated data depends on the first field (`spi_index`): 0 is a forbidden SPI
30		/// index, and indicates that the header is an IKE header.
31		/// Any other value indicates an ESP header.
32		///
33		/// Note: input is entirely consumed
34	0	pub fn parse_esp_encapsulated(i: &[u8]) -> IResult<&[u8], ESPData> {
35	0	if be_u32(i)?.1 == 0 {
36	0	parse_ikev2_header(i).map(\|x\| (x.0, ESPData::IKE(x.1))) Unexecuted instantiation: ipsec_parser::esp::parse_esp_encapsulated::{closure#0} Unexecuted instantiation: ipsec_parser::esp::parse_esp_encapsulated::{closure#0}
37		} else {
38	0	parse_esp_header(i).map(\|x\| (x.0, ESPData::ESP(x.1))) Unexecuted instantiation: ipsec_parser::esp::parse_esp_encapsulated::{closure#1} Unexecuted instantiation: ipsec_parser::esp::parse_esp_encapsulated::{closure#1}
39		}
40	0	} Unexecuted instantiation: ipsec_parser::esp::parse_esp_encapsulated Unexecuted instantiation: ipsec_parser::esp::parse_esp_encapsulated
41
42		/// Parse an ESP packet
43		///
44		/// The ESP header contains:
45		///
46		/// - the SPI index
47		/// - the sequence number
48		/// - the payload data (which can be encrypted)
49		///
50		/// Note: input is entirely consumed
51	0	pub fn parse_esp_header(i: &[u8]) -> IResult<&[u8], ESPHeader> {
52	0	let (i, spi_index) = take(4usize)(i)?;
53	0	let (i, seq) = be_u32(i)?;
54	0	let (i, data) = rest(i)?;
55	0	let hdr = ESPHeader {
56	0	spi_index,
57	0	seq,
58	0	data,
59	0	};
60	0	Ok((i, hdr))
61	0	} Unexecuted instantiation: ipsec_parser::esp::parse_esp_header Unexecuted instantiation: ipsec_parser::esp::parse_esp_header