Expect object handling

Functions
struct nf_expect *	nfexp_new (void)
void	nfexp_destroy (struct nf_expect *exp)
size_t	nfexp_sizeof (const struct nf_expect *exp)
size_t	nfexp_maxsize (void)
struct nf_expect *	nfexp_clone (const struct nf_expect *exp)
int	nfexp_cmp (const struct nf_expect *exp1, const struct nf_expect *exp2, unsigned int flags)
void	nfexp_set_attr (struct nf_expect *exp, const enum nf_expect_attr type, const void *value)
void	nfexp_set_attr_u8 (struct nf_expect *exp, const enum nf_expect_attr type, uint8_t value)
void	nfexp_set_attr_u16 (struct nf_expect *exp, const enum nf_expect_attr type, uint16_t value)
void	nfexp_set_attr_u32 (struct nf_expect *exp, const enum nf_expect_attr type, uint32_t value)
const void *	nfexp_get_attr (const struct nf_expect *exp, const enum nf_expect_attr type)
uint8_t	nfexp_get_attr_u8 (const struct nf_expect *exp, const enum nf_expect_attr type)
uint16_t	nfexp_get_attr_u16 (const struct nf_expect *exp, const enum nf_expect_attr type)
uint32_t	nfexp_get_attr_u32 (const struct nf_expect *exp, const enum nf_expect_attr type)
int	nfexp_attr_is_set (const struct nf_expect *exp, const enum nf_expect_attr type)
int	nfexp_attr_unset (struct nf_expect *exp, const enum nf_expect_attr type)
int	nfexp_snprintf (char *buf, unsigned int size, const struct nf_expect *exp, unsigned int msg_type, unsigned int out_type, unsigned int flags)

Detailed Description

Function Documentation

int nfexp_attr_is_set	(	const struct nf_expect *	exp,
		const enum nf_expect_attr	type
	)

nfexp_attr_is_set - check if a certain attribute is set

Parameters

exp	pointer to a valid expectation object
type	attribute type

On error, -1 is returned and errno is set appropiately, otherwise the value of the attribute is returned.

Definition at line 445 of file expect/api.c.

int nfexp_attr_unset	(	struct nf_expect *	exp,
		const enum nf_expect_attr	type
	)

nfexp_attr_unset - unset a certain attribute

Parameters

type	attribute type
exp	pointer to a valid expectation object

On error, -1 is returned and errno is set appropiately, otherwise 0 is returned.

Definition at line 465 of file expect/api.c.

struct nf_expect* nfexp_clone

(

const struct nf_expect *

exp

)

nfexp_clone - clone a expectation object

Parameters

exp	pointer to a valid expectation object

On error, NULL is returned and errno is appropiately set. Otherwise, a valid pointer to the clone expect is returned.

Definition at line 88 of file expect/api.c.

int nfexp_cmp	(	const struct nf_expect *	exp1,
		const struct nf_expect *	exp2,
		unsigned int	flags
	)

nfexp_cmp - compare two expectation objects

Parameters

exp1	pointer to a valid expectation object
exp2	pointer to a valid expectation object
flags	flags

This function only compare attribute set in both objects, by default the comparison is not strict, ie. if a certain attribute is not set in one of the objects, then such attribute is not used in the comparison. If you want more strict comparisons, you can use the appropriate flags to modify this behaviour (see NFCT_CMP_STRICT and NFCT_CMP_MASK).

The available flags are:

• NFCT_CMP_STRICT: the compared objects must have the same attributes and the same values, otherwise it returns that the objects are different.
• NFCT_CMP_MASK: the first object is used as mask, this means that if an attribute is present in exp1 but not in exp2, this function returns that the objects are different.

Other existing flags that are used by nfct_cmp() are ignored.

If both conntrack object are equal, this function returns 1, otherwise 0 is returned.

Definition at line 126 of file expect/api.c.

void nfexp_destroy

(

struct nf_expect *

exp

)

nfexp_destroy - release an expectation object

Parameters

exp	pointer to the expectation object

Definition at line 45 of file expect/api.c.

const void* nfexp_get_attr	(	const struct nf_expect *	exp,
		const enum nf_expect_attr	type
	)

nfexp_get_attr - get an expect attribute

Parameters

exp	pointer to a valid expect
type	attribute type

In case of success a valid pointer to the attribute requested is returned, on error NULL is returned and errno is set appropiately.

Definition at line 371 of file expect/api.c.

uint16_t nfexp_get_attr_u16	(	const struct nf_expect *	exp,
		const enum nf_expect_attr	type
	)

nfexp_get_attr_u16 - get attribute of unsigned 16-bits long

Parameters

exp	pointer to a valid expectation
type	attribute type

Returns the value of the requested attribute, if the attribute is not set, 0 is returned. In order to check if the attribute is set or not, use nfexp_attr_is_set.

Definition at line 414 of file expect/api.c.

uint32_t nfexp_get_attr_u32	(	const struct nf_expect *	exp,
		const enum nf_expect_attr	type
	)

nfexp_get_attr_u32 - get attribute of unsigned 32-bits long

Parameters

exp	pointer to a valid expectation
type	attribute type

Returns the value of the requested attribute, if the attribute is not set, 0 is returned. In order to check if the attribute is set or not, use nfexp_attr_is_set.

Definition at line 430 of file expect/api.c.

uint8_t nfexp_get_attr_u8	(	const struct nf_expect *	exp,
		const enum nf_expect_attr	type
	)

nfexp_get_attr_u8 - get attribute of unsigned 8-bits long

Parameters

exp	pointer to a valid expectation
type	attribute type

Returns the value of the requested attribute, if the attribute is not set, 0 is returned. In order to check if the attribute is set or not, use nfexp_attr_is_set.

Definition at line 398 of file expect/api.c.

size_t nfexp_maxsize

(

void

)

nfexp_maxsize - return the maximum size in bytes of a expect object

Use this function if you want to allocate a expect object in the stack instead of the heap. For example:

char buf[nfexp_maxsize()]; struct nf_expect *exp = (struct nf_expect *) buf; memset(exp, 0, nfexp_maxsize());

Note: As for now this function returns the same size that nfexp_sizeof(exp) does although this could change in the future. Therefore, do not assume that nfexp_sizeof(exp) == nfexp_maxsize().

Definition at line 76 of file expect/api.c.

struct nf_expect* nfexp_new

(

void

)

nfexp_new - allocate a new expectation

In case of success, this function returns a valid pointer to a memory blob, otherwise NULL is returned and errno is set appropiately.

Definition at line 28 of file expect/api.c.

void nfexp_set_attr	(	struct nf_expect *	exp,
		const enum nf_expect_attr	type,
		const void *	value
	)

nfexp_set_attr - set the value of a certain expect attribute

Parameters

exp	pointer to a valid expect
type	attribute type
value	pointer to the attribute value

Note that certain attributes are unsettable:

• ATTR_EXP_USE
• ATTR_EXP_ID
• ATTR_EXP_*_COUNTER_* The call of this function for such attributes do nothing.

Definition at line 308 of file expect/api.c.

void nfexp_set_attr_u16	(	struct nf_expect *	exp,
		const enum nf_expect_attr	type,
		uint16_t	value
	)

nfexp_set_attr_u16 - set the value of a certain expect attribute

Parameters

exp	pointer to a valid expect
type	attribute type
value	unsigned 16 bits attribute value

Definition at line 343 of file expect/api.c.

void nfexp_set_attr_u32	(	struct nf_expect *	exp,
		const enum nf_expect_attr	type,
		uint32_t	value
	)

nfexp_set_attr_u32 - set the value of a certain expect attribute

Parameters

exp	pointer to a valid expect
type	attribute type
value	unsigned 32 bits attribute value

Definition at line 356 of file expect/api.c.

void nfexp_set_attr_u8	(	struct nf_expect *	exp,
		const enum nf_expect_attr	type,
		uint8_t	value
	)

nfexp_set_attr_u8 - set the value of a certain expect attribute

Parameters

exp	pointer to a valid expect
type	attribute type
value	unsigned 8 bits attribute value

Definition at line 330 of file expect/api.c.

size_t nfexp_sizeof

(

const struct nf_expect *

exp

)

nfexp_sizeof - return the size in bytes of a certain expect object

Parameters

exp	pointer to the expect object

Definition at line 56 of file expect/api.c.

int nfexp_snprintf	(	char *	buf,
		unsigned int	size,
		const struct nf_expect *	exp,
		unsigned int	msg_type,
		unsigned int	out_type,
		unsigned int	flags
	)

nfexp_snprintf - print a conntrack object to a buffer

Parameters

buf	buffer used to build the printable conntrack
size	size of the buffer
exp	pointer to a valid expectation object
message_type	print message type (NFEXP_T_UNKNOWN, NFEXP_T_NEW,...)
output_type	print type (NFEXP_O_DEFAULT, NFEXP_O_XML, ...)
flags	extra flags for the output type (NFEXP_OF_LAYER3)

If you are listening to events, probably you want to display the message type as well. In that case, set the message type parameter to any of the known existing types, ie. NFEXP_T_NEW, NFEXP_T_UPDATE, NFEXP_T_DESTROY. If you pass NFEXP_T_UNKNOWN, the message type will not be output.

Currently, the output available are:

• NFEXP_O_DEFAULT: default /proc-like output
• NFEXP_O_XML: XML output

The output flags are:

• NFEXP_O_LAYER: include layer 3 information in the output, this is only required by NFEXP_O_DEFAULT.

On error, -1 is returned and errno is set appropiately. Otherwise, 0 is returned.

Definition at line 774 of file expect/api.c.