ip.c File Reference

IP-agnostic packet. More...

#include "ip.h"
#include "rohc_utils.h"
#include "protocols/ip_numbers.h"
#include "protocols/ipv4.h"
#include "protocols/ipv6.h"
#include <string.h>
#include <assert.h>

Include dependency graph for ip.c:

Functions
static bool	ip_find_next_layer (const struct ip_packet *const ip, struct net_hdr *const nh, struct net_hdr *const nl)
	Find the next header and next layer transported by an IP packet.
static bool	ext_get_next_layer (const struct net_hdr *const nh, struct net_hdr *const nl)
	Find the next layer transported by an IP extension.
static bool	ext_get_next_header (const uint8_t *const ext, const size_t ext_len, struct net_hdr *const nh)
	Find the next header transported by an IP extension.
bool	ip_create (struct ip_packet *const ip, const uint8_t *const packet, const size_t size)
	Create an IP packet from raw data.
const uint8_t *	ip_get_raw_data (const struct ip_packet *const ip)
	Get the IP raw data (header + payload).
bool	ip_get_inner_packet (const struct ip_packet *const outer, struct ip_packet *const inner)
	Get the inner IP packet (IP in IP).
uint8_t *	ip_get_next_header (const struct ip_packet *const ip, uint8_t *const type)
	Get the IP next header.
uint8_t *	ip_get_next_layer (const struct ip_packet *const ip)
	Get the next header (but skip IP extensions).
uint8_t *	ip_get_next_ext_from_ip (const struct ip_packet *const ip, uint8_t *const type)
	Get the next extension header of IPv6 packets from an IPv6 header.
uint8_t *	ip_get_next_ext_from_ext (const uint8_t *const ext, uint8_t *const type)
	Get the next extension header of IPv6 packets from another extension.
unsigned short	ip_get_extension_size (const uint8_t *const ext)
	Get the size of an IPv6 extension.
unsigned short	ip_get_total_extension_size (const struct ip_packet *const ip)
	Get the size of the extension list.
bool	ip_is_fragment (const struct ip_packet *const ip)
	Whether the IP packet is an IP fragment or not.
unsigned int	ip_get_totlen (const struct ip_packet *const ip)
	Get the total length of an IP packet.
unsigned int	ip_get_hdrlen (const struct ip_packet *const ip)
	Get the length of an IP header.
ip_version	ip_get_version (const struct ip_packet *const ip)
	Get the IP version of an IP packet.
void	ip_set_version (struct ip_packet *const ip, const ip_version value)
	Set the IP version of an IP packet.
uint8_t	ip_get_protocol (const struct ip_packet *const ip)
	Get the protocol transported by an IP packet.
void	ip_set_protocol (struct ip_packet *const ip, const uint8_t value)
	Set the protocol transported by an IP packet.
unsigned int	ip_get_tos (const struct ip_packet *const ip)
	Get the IPv4 Type Of Service (TOS) or IPv6 Traffic Class (TC) of an IP packet.
void	ip_set_tos (struct ip_packet *const ip, const uint8_t value)
	Set the IPv4 Type Of Service (TOS) or IPv6 Traffic Class (TC) of an IP packet.
unsigned int	ip_get_ttl (const struct ip_packet *const ip)
	Get the IPv4 Time To Live (TTL) or IPv6 Hop Limit (HL) of an IP packet.
void	ip_set_ttl (struct ip_packet *const ip, const uint8_t value)
	Set the IPv4 Time To Live (TTL) or IPv6 Hop Limit (HL) of an IP packet.
void	ip_set_saddr (struct ip_packet *const ip, const uint8_t *value)
	Set the Source Address of an IP packet.
void	ip_set_daddr (struct ip_packet *const ip, const uint8_t *value)
	Set the Destination Address of an IP packet.
struct ipv4_hdr *	ipv4_get_header (const struct ip_packet *const ip)
	Get the IPv4 header.
uint16_t	ipv4_get_id (const struct ip_packet *const ip)
	Get the IP-ID of an IPv4 packet.
uint16_t	ipv4_get_id_nbo (const struct ip_packet *const ip, const unsigned int nbo)
	Get the IP-ID of an IPv4 packet in Network Byte Order.
void	ipv4_set_id (struct ip_packet *const ip, const int value)
	Set the IP-ID of an IPv4 packet.
int	ipv4_get_df (const struct ip_packet *const ip)
	Get the Don't Fragment (DF) bit of an IPv4 packet.
void	ipv4_set_df (struct ip_packet *const ip, const int value)
	Set the Don't Fragment (DF) bit of an IPv4 packet.
uint32_t	ipv4_get_saddr (const struct ip_packet *const ip)
	Get the source address of an IPv4 packet.
uint32_t	ipv4_get_daddr (const struct ip_packet *const ip)
	Get the destination address of an IPv4 packet.
struct ipv6_hdr *	ipv6_get_header (const struct ip_packet *const ip)
	Get the IPv6 header.
uint32_t	ip_get_flow_label (const struct ip_packet *const ip)
	Get the flow label of an IPv6 packet.
void	ip_set_flow_label (struct ip_packet *const ip, const uint32_t value)
	Set the flow label of an IPv6 packet.
struct ipv6_addr *	ipv6_get_saddr (const struct ip_packet *const ip)
	Get the source address of an IPv6 packet.
struct ipv6_addr *	ipv6_get_daddr (const struct ip_packet *const ip)
	Get the destination address of an IPv6 packet.

---

Detailed Description

IP-agnostic packet.

Author:

Didier Barvaux <didier.barvaux@toulouse.viveris.com>

Didier Barvaux <didier@barvaux.org>

---

Function Documentation

static bool ext_get_next_header	(	const uint8_t *const	ext,
		const size_t	ext_len,
		struct net_hdr *const	nh
	)			[static]

Find the next header transported by an IP extension.

Parameters:

	ext	The extension header
	ext_len	The maximum length of the extension
[out]	nh	The next header transported by the extension header

Returns:

true if the extension is well-formed, false otherwise

static bool ext_get_next_layer	(	const struct net_hdr *const	nh,
		struct net_hdr *const	nl
	)			[static]

Find the next layer transported by an IP extension.

Parameters:

	nh	The first IP extension
[out]	nl	The next layer

Returns:

true if all extensions are well-formed, false otherwise

bool ip_create	(	struct ip_packet *const	ip,
		const uint8_t *const	packet,
		const size_t	size
	)

Create an IP packet from raw data.

Parameters:

	ip	OUT: The IP packet to create
	packet	The IP packet data
	size	The length of the IP packet data

Returns:

Whether the IP packet was successfully created or not

static bool ip_find_next_layer	(	const struct ip_packet *const	ip,
		struct net_hdr *const	nh,
		struct net_hdr *const	nl
	)			[static]

Find the next header and next layer transported by an IP packet.

Private functions used by the IP module: (please do not use directly)

Parameters:

	ip	The IP packet to analyze
[out]	nh	The first IP extension or the transport layer
[out]	nl	The transport layer

Returns:

true if all extensions are well-formed, false otherwise

unsigned short ip_get_extension_size

(

const uint8_t *const

ext

)

Get the size of an IPv6 extension.

Parameters:

ext

The extension

Returns:

The size of the extension

uint32_t ip_get_flow_label

(

const struct ip_packet *const

ip

)

Get the flow label of an IPv6 packet.

The function does not handle ip_packet whose ip_packet::version is not IPV6.

Parameters:

ip

The IPv6 packet to analyze

Returns:

The flow label of the given IPv6 packet

unsigned int ip_get_hdrlen

(

const struct ip_packet *const

ip

)

Get the length of an IP header.

The function does not handle ip_packet whose ip_packet::version is IP_UNKNOWN.

Parameters:

ip

The IP packet to analyze

Returns:

The length of the IP header if successful, 0 otherwise

bool ip_get_inner_packet	(	const struct ip_packet *const	outer,
		struct ip_packet *const	inner
	)

Get the inner IP packet (IP in IP).

The function does not handle ip_packet whose ip_packet::version is IP_UNKNOWN.

Parameters:

	outer	The outer IP packet to analyze
	inner	The inner IP packet to create

Returns:

Whether the inner IP header is successfully created or not

uint8_t* ip_get_next_ext_from_ext	(	const uint8_t *const	ext,
		uint8_t *const	type
	)

Get the next extension header of IPv6 packets from another extension.

Parameters:

	ext	The extension to analyse
	type	OUT: The type of the next header If there is no next header the value must be ignored

Returns:

The next extension header, NULL if there is no more extension

uint8_t* ip_get_next_ext_from_ip	(	const struct ip_packet *const	ip,
		uint8_t *const	type
	)

Get the next extension header of IPv6 packets from an IPv6 header.

The function does not handle ip_packet whose ip_packet::version is IP_UNKNOWN.

Parameters:

	ip	The IP packet to analyze
	type	OUT: The type of the next header If there is no next header the value must be ignored

Returns:

The next extension header, NULL if there is no extension

uint8_t* ip_get_next_header	(	const struct ip_packet *const	ip,
		uint8_t *const	type
	)

Get the IP next header.

The function does not handle ip_packet whose ip_packet::version is IP_UNKNOWN.

Parameters:

	ip	The IP packet to analyze
	type	OUT: The type of the next header

Returns:

The next header if successful, NULL otherwise

uint8_t* ip_get_next_layer

(

const struct ip_packet *const

ip

)

Get the next header (but skip IP extensions).

The function does not handle ip_packet whose ip_packet::version is IP_UNKNOWN.

Parameters:

ip

The IP packet to analyze

Returns:

The next header that is not an IP extension if there is one, NULL if there is none

uint8_t ip_get_protocol

(

const struct ip_packet *const

ip

)

Get the protocol transported by an IP packet.

The protocol returned is the one transported by the last known IP extension header if any is found.

The function handles ip_packet whose ip_packet::version is IP_UNKNOWN. It always returns the special value 0.

Parameters:

ip

The IP packet to analyze

Returns:

The protocol number that identify the protocol transported by the given IP packet, 0 if the packet is not IPv4 nor IPv6

const uint8_t* ip_get_raw_data

(

const struct ip_packet *const

ip

)

Get the IP raw data (header + payload).

The function handles ip_packet whose ip_packet::version is IP_UNKNOWN.

Parameters:

ip

The IP packet to analyze

Returns:

The IP raw data (header + payload)

unsigned int ip_get_tos

(

const struct ip_packet *const

ip

)

Get the IPv4 Type Of Service (TOS) or IPv6 Traffic Class (TC) of an IP packet.

The function does not handle ip_packet whose ip_packet::version is IP_UNKNOWN.

Parameters:

ip

The IP packet to analyze

Returns:

The TOS or TC value if successful, 0 otherwise

unsigned short ip_get_total_extension_size

(

const struct ip_packet *const

ip

)

Get the size of the extension list.

The function does not handle ip_packet whose ip_packet::version is IP_UNKNOWN.

Parameters:

ip

The packet to analyse

Returns:

The size of extension list

unsigned int ip_get_totlen

(

const struct ip_packet *const

ip

)

Get the total length of an IP packet.

The function handles ip_packet whose ip_packet::version is IP_UNKNOWN.

Parameters:

ip

The IP packet to analyze

Returns:

The total length of the IP packet

unsigned int ip_get_ttl

(

const struct ip_packet *const

ip

)

Get the IPv4 Time To Live (TTL) or IPv6 Hop Limit (HL) of an IP packet.

The function does not handle ip_packet whose ip_packet::version is IP_UNKNOWN.

Parameters:

ip

The IP packet to analyze

Returns:

The TTL or HL value if successful, 0 otherwise

ip_version ip_get_version

(

const struct ip_packet *const

ip

)

Get the IP version of an IP packet.

The function handles ip_packet whose ip_packet::version is IP_UNKNOWN.

Parameters:

ip

The IP packet to analyze

Returns:

The version of the IP packet

bool ip_is_fragment

(

const struct ip_packet *const

ip

)

Whether the IP packet is an IP fragment or not.

The IP packet is a fragment if the MF (More Fragments) bit is set or the Fragment Offset field is non-zero.

The function does not handle ip_packet whose ip_packet::version is IP_UNKNOWN.

Parameters:

ip

The IP packet to analyze

Returns:

Whether the IP packet is an IP fragment or not

void ip_set_daddr	(	struct ip_packet *const	ip,
		const uint8_t *	value
	)

Set the Destination Address of an IP packet.

The function does not handle ip_packet whose ip_packet::version is IP_UNKNOWN.

Parameters:

	ip	The IP packet to modify
	value	The IP address value

void ip_set_flow_label	(	struct ip_packet *const	ip,
		const uint32_t	value
	)

Set the flow label of an IPv6 packet.

The function does not handle ip_packet whose ip_packet::version is not IPV6.

Parameters:

	ip	The IPv6 packet to modify
	value	The flow label value

void ip_set_protocol	(	struct ip_packet *const	ip,
		const uint8_t	value
	)

Set the protocol transported by an IP packet.

The function does not handle ip_packet whose ip_packet::version is IP_UNKNOWN.

Parameters:

	ip	The IP packet to modify
	value	The protocol value

void ip_set_saddr	(	struct ip_packet *const	ip,
		const uint8_t *	value
	)

Set the Source Address of an IP packet.

The function does not handle ip_packet whose ip_packet::version is IP_UNKNOWN.

Parameters:

	ip	The IP packet to modify
	value	The IP address value

void ip_set_tos	(	struct ip_packet *const	ip,
		const uint8_t	value
	)

Set the IPv4 Type Of Service (TOS) or IPv6 Traffic Class (TC) of an IP packet.

The function does not handle ip_packet whose ip_packet::version is IP_UNKNOWN.

Parameters:

	ip	The IP packet to modify
	value	The TOS/TC value

void ip_set_ttl	(	struct ip_packet *const	ip,
		const uint8_t	value
	)

Set the IPv4 Time To Live (TTL) or IPv6 Hop Limit (HL) of an IP packet.

The function does not handle ip_packet whose ip_packet::version is IP_UNKNOWN.

Parameters:

	ip	The IP packet to modify
	value	The TTL/HL value

void ip_set_version	(	struct ip_packet *const	ip,
		const ip_version	value
	)

Set the IP version of an IP packet.

Parameters:

	ip	The IP packet to modify
	value	The version value

uint32_t ipv4_get_daddr

(

const struct ip_packet *const

ip

)

Get the destination address of an IPv4 packet.

The function does not handle ip_packet whose ip_packet::version is not IPV4.

Parameters:

ip

The IPv4 packet to analyze

Returns:

The source address of the given IPv4 packet

int ipv4_get_df

(

const struct ip_packet *const

ip

)

Get the Don't Fragment (DF) bit of an IPv4 packet.

The function does not handle ip_packet whose ip_packet::version is not IPV4.

Parameters:

ip

The IP packet to analyze

Returns:

The DF bit

struct ipv4_hdr* ipv4_get_header

(

const struct ip_packet *const

ip

)

[read]

Get the IPv4 header.

The function does not handle ip_packet whose ip_packet::version is not IPV4.

Parameters:

ip

The IP packet to analyze

Returns:

The IP header

uint16_t ipv4_get_id

(

const struct ip_packet *const

ip

)

Get the IP-ID of an IPv4 packet.

The IP-ID value is returned as-is (ie. not automatically converted to the host byte order).

The function does not handle ip_packet whose ip_packet::version is not IPV4.

Parameters:

ip

The IP packet to analyze

Returns:

The IP-ID

uint16_t ipv4_get_id_nbo	(	const struct ip_packet *const	ip,
		const unsigned int	nbo
	)

Get the IP-ID of an IPv4 packet in Network Byte Order.

The function does not handle ip_packet whose ip_packet::version is not IPV4.

Parameters:

	ip	The IP packet to analyze
	nbo	The NBO flag (if RND = 1, use NBO = 1)

Returns:

The IP-ID

uint32_t ipv4_get_saddr

(

const struct ip_packet *const

ip

)

Get the source address of an IPv4 packet.

The function does not handle ip_packet whose ip_packet::version is not IPV4.

Parameters:

ip

The IPv4 packet to analyze

Returns:

The source address of the given IPv4 packet

void ipv4_set_df	(	struct ip_packet *const	ip,
		const int	value
	)

Set the Don't Fragment (DF) bit of an IPv4 packet.

The function does not handle ip_packet whose ip_packet::version is not IPV4.

Parameters:

	ip	The IP packet to modify
	value	The value of the DF bit

void ipv4_set_id	(	struct ip_packet *const	ip,
		const int	value
	)

Set the IP-ID of an IPv4 packet.

The IP-ID value is set as-is (ie. not automatically converted to the host byte order).

The function does not handle ip_packet whose ip_packet::version is not IPV4.

Parameters:

	ip	The IP packet to modify
	value	The IP-ID value

struct ipv6_addr* ipv6_get_daddr

(

const struct ip_packet *const

ip

)

[read]

Get the destination address of an IPv6 packet.

The function does not handle ip_packet whose ip_packet::version is not IPV6.

Parameters:

ip

The IPv6 packet to analyze

Returns:

The source address of the given IPv6 packet

struct ipv6_hdr* ipv6_get_header

(

const struct ip_packet *const

ip

)

[read]

Get the IPv6 header.

The function does not handle ip_packet whose ip_packet::version is not IPV6.

Parameters:

ip

The IP packet to analyze

Returns:

The IP header if IPv6

struct ipv6_addr* ipv6_get_saddr

(

const struct ip_packet *const

ip

)

[read]

Get the source address of an IPv6 packet.

The function does not handle ip_packet whose ip_packet::version is not IPV6.

Parameters:

ip

The IPv6 packet to analyze

Returns:

The source address of the given IPv6 packet