[thirdparty/bird.git] / lib / flowspec.h

/*
 *	BIRD Library -- Flow specification (RFC 5575)
 *
 *	(c) 2016 CZ.NIC z.s.p.o.
 *
 *	Can be freely distributed and used under the terms of the GNU GPL.
 */

#ifndef _BIRD_FLOWSPEC_H_
#define _BIRD_FLOWSPEC_H_

#include "nest/bird.h"
#include "lib/buffer.h"
#include "lib/net.h"


/* Flow component operators */
#define FLOW_OP_TRUE		0x00	/* 0b000 */
#define FLOW_OP_EQ		0x01	/* 0b001 */
#define FLOW_OP_GT		0x02	/* 0b010 */
#define FLOW_OP_GEQ		0x03	/* 0b011 */
#define FLOW_OP_LT		0x04	/* 0b100 */
#define FLOW_OP_LEQ		0x05	/* 0b101 */
#define FLOW_OP_NEQ		0x06	/* 0b110 */
#define FLOW_OP_FALSE		0x07	/* 0b111 */

#define FLOW_OP_OR		0x00
#define FLOW_OP_AND		0x40


/* Types of components in flowspec */
enum flow_type {
  FLOW_TYPE_DST_PREFIX 		=  1,
  FLOW_TYPE_SRC_PREFIX 		=  2,
  FLOW_TYPE_IP_PROTOCOL 	=  3,
  FLOW_TYPE_NEXT_HEADER 	=  3,	/* IPv6 */
  FLOW_TYPE_PORT 		=  4,
  FLOW_TYPE_DST_PORT 		=  5,
  FLOW_TYPE_SRC_PORT 		=  6,
  FLOW_TYPE_ICMP_TYPE 		=  7,
  FLOW_TYPE_ICMP_CODE 		=  8,
  FLOW_TYPE_TCP_FLAGS 		=  9,
  FLOW_TYPE_PACKET_LENGTH 	= 10,
  FLOW_TYPE_DSCP 		= 11,	/* DiffServ Code Point */
  FLOW_TYPE_FRAGMENT 		= 12,
  FLOW_TYPE_LABEL 		= 13,	/* IPv6 */
  FLOW_TYPE_MAX
};

const char *flow_type_str(enum flow_type type, int ipv6);


/*
 * 	Length
 */

uint flow_write_length(byte *data, u16 len);

static inline u16 flow_hdr_length(const byte *data)
{ return ((*data & 0xf0) == 0xf0) ? 2 : 1; }

static inline u16 flow_read_length(const byte *data)
{ return ((*data & 0xf0) == 0xf0) ? get_u16(data) & 0x0fff : *data; }

static inline u16 flow4_get_length(const net_addr_flow4 *f)
{ return f->length - sizeof(net_addr_flow4); }

static inline u16 flow6_get_length(const net_addr_flow6 *f)
{ return f->length - sizeof(net_addr_flow6); }

static inline void flow4_set_length(net_addr_flow4 *f, u16 len)
{ f->length = sizeof(net_addr_flow4) + flow_write_length(f->data, len) + len; }

static inline void flow6_set_length(net_addr_flow6 *f, u16 len)
{ f->length = sizeof(net_addr_flow6) + flow_write_length(f->data, len) + len; }


/*
 * 	Iterators
 */

const byte *flow4_first_part(const net_addr_flow4 *f);
const byte *flow6_first_part(const net_addr_flow6 *f);
const byte *flow4_next_part(const byte *pos, const byte *end);
const byte *flow6_next_part(const byte *pos, const byte *end);


/*
 * 	Flowspec Builder
 */

/* A data structure for keep a state of flow builder */
struct flow_builder {
  BUFFER(byte) data;
  enum flow_type this_type;
  enum flow_type last_type;
  u16 last_op_offset;			/* Position of last operator in data.data */
  int ipv6;
  struct {
    u16 offset;				/* Beginning of a component */
    u16 length;				/* Length of a component */
  } parts[FLOW_TYPE_MAX];		/* Indexing all components */
};

struct flow_builder *flow_builder_init(pool *pool);
void flow_builder_clear(struct flow_builder *fb);
void flow_builder_set_type(struct flow_builder *fb, enum flow_type p);
int flow_builder4_add_pfx(struct flow_builder *fb, const net_addr_ip4 *n4);
int flow_builder6_add_pfx(struct flow_builder *fb, const net_addr_ip6 *n6, u32 offset);
int flow_builder_add_op_val(struct flow_builder *fb, byte op, u32 value);
int flow_builder_add_val_mask(struct flow_builder *fb, byte op, u32 value, u32 mask);
net_addr_flow4 *flow_builder4_finalize(struct flow_builder *fb, linpool *lpool);
net_addr_flow6 *flow_builder6_finalize(struct flow_builder *fb, linpool *lpool);


/*
 * 	Validation
 */

/* Results of validation Flow specification */
enum flow_validated_state {
  FLOW_ST_UNKNOWN_COMPONENT,
  FLOW_ST_VALID,
  FLOW_ST_NOT_COMPLETE,
  FLOW_ST_EXCEED_MAX_PREFIX_LENGTH,
  FLOW_ST_EXCEED_MAX_PREFIX_OFFSET,
  FLOW_ST_EXCEED_MAX_VALUE_LENGTH,
  FLOW_ST_BAD_TYPE_ORDER,
  FLOW_ST_AND_BIT_SHOULD_BE_UNSET,
  FLOW_ST_ZERO_BIT_SHOULD_BE_UNSED,
  FLOW_ST_DEST_PREFIX_REQUIRED,
  FLOW_ST_INVALID_TCP_FLAGS,
  FLOW_ST_CANNOT_USE_DONT_FRAGMENT
};

const char *flow_validated_state_str(enum flow_validated_state code);
enum flow_validated_state flow4_validate(const byte *nlri, uint len);
enum flow_validated_state flow6_validate(const byte *nlri, uint len);
void flow_check_cf_value_length(struct flow_builder *fb, u32 expr);
void flow_check_cf_bmk_values(struct flow_builder *fb, u8 neg, u32 val, u32 mask);
void flow4_validate_cf(net_addr_flow4 *f);
void flow6_validate_cf(net_addr_flow6 *f);


/*
 * 	Net Formatting
 */

uint flow4_net_format(char *buf, uint blen, const net_addr_flow4 *f);
uint flow6_net_format(char *buf, uint blen, const net_addr_flow6 *f);

#endif /* _BIRD_FLOWSPEC_H_ */
Commit	Line	Data
77234bbb OZ	1	/*
	2	* BIRD Library -- Flow specification (RFC 5575)
	3	*
	4	* (c) 2016 CZ.NIC z.s.p.o.
	5	*
	6	* Can be freely distributed and used under the terms of the GNU GPL.
	7	*/
	8
	9	#ifndef _BIRD_FLOWSPEC_H_
	10	#define _BIRD_FLOWSPEC_H_
	11
	12	#include "nest/bird.h"
	13	#include "lib/buffer.h"
	14	#include "lib/net.h"
	15
	16
734e9fb8 OZ	17	/* Flow component operators */
	18	#define FLOW_OP_TRUE 0x00 /* 0b000 */
	19	#define FLOW_OP_EQ 0x01 /* 0b001 */
	20	#define FLOW_OP_GT 0x02 /* 0b010 */
	21	#define FLOW_OP_GEQ 0x03 /* 0b011 */
	22	#define FLOW_OP_LT 0x04 /* 0b100 */
	23	#define FLOW_OP_LEQ 0x05 /* 0b101 */
	24	#define FLOW_OP_NEQ 0x06 /* 0b110 */
	25	#define FLOW_OP_FALSE 0x07 /* 0b111 */
	26
	27	#define FLOW_OP_OR 0x00
	28	#define FLOW_OP_AND 0x40
	29
	30
77234bbb OZ	31	/* Types of components in flowspec */
	32	enum flow_type {
	33	FLOW_TYPE_DST_PREFIX = 1,
	34	FLOW_TYPE_SRC_PREFIX = 2,
	35	FLOW_TYPE_IP_PROTOCOL = 3,
	36	FLOW_TYPE_NEXT_HEADER = 3, /* IPv6 */
	37	FLOW_TYPE_PORT = 4,
	38	FLOW_TYPE_DST_PORT = 5,
	39	FLOW_TYPE_SRC_PORT = 6,
	40	FLOW_TYPE_ICMP_TYPE = 7,
	41	FLOW_TYPE_ICMP_CODE = 8,
	42	FLOW_TYPE_TCP_FLAGS = 9,
	43	FLOW_TYPE_PACKET_LENGTH = 10,
	44	FLOW_TYPE_DSCP = 11, /* DiffServ Code Point */
	45	FLOW_TYPE_FRAGMENT = 12,
	46	FLOW_TYPE_LABEL = 13, /* IPv6 */
	47	FLOW_TYPE_MAX
	48	};
	49
	50	const char *flow_type_str(enum flow_type type, int ipv6);
	51
	52
	53	/*
	54	* Length
	55	*/
	56
	57	uint flow_write_length(byte *data, u16 len);
	58
ac3ad139 OZ	59	static inline u16 flow_hdr_length(const byte *data)
	60	{ return ((*data & 0xf0) == 0xf0) ? 2 : 1; }
	61
77234bbb OZ	62	static inline u16 flow_read_length(const byte *data)
	63	{ return ((data & 0xf0) == 0xf0) ? get_u16(data) & 0x0fff : data; }
	64
	65	static inline u16 flow4_get_length(const net_addr_flow4 *f)
	66	{ return f->length - sizeof(net_addr_flow4); }
	67
	68	static inline u16 flow6_get_length(const net_addr_flow6 *f)
	69	{ return f->length - sizeof(net_addr_flow6); }
	70
	71	static inline void flow4_set_length(net_addr_flow4 *f, u16 len)
	72	{ f->length = sizeof(net_addr_flow4) + flow_write_length(f->data, len) + len; }
	73
	74	static inline void flow6_set_length(net_addr_flow6 *f, u16 len)
	75	{ f->length = sizeof(net_addr_flow6) + flow_write_length(f->data, len) + len; }
	76
	77
	78	/*
	79	* Iterators
	80	*/
	81
	82	const byte flow4_first_part(const net_addr_flow4 f);
	83	const byte flow6_first_part(const net_addr_flow6 f);
	84	const byte flow4_next_part(const byte pos, const byte *end);
	85	const byte flow6_next_part(const byte pos, const byte *end);
	86
	87
	88	/*
	89	* Flowspec Builder
	90	*/
	91
	92	/* A data structure for keep a state of flow builder */
	93	struct flow_builder {
	94	BUFFER(byte) data;
	95	enum flow_type this_type;
	96	enum flow_type last_type;
	97	u16 last_op_offset; /* Position of last operator in data.data */
	98	int ipv6;
	99	struct {
	100	u16 offset; /* Beginning of a component */
	101	u16 length; /* Length of a component */
	102	} parts[FLOW_TYPE_MAX]; /* Indexing all components */
	103	};
	104
	105	struct flow_builder flow_builder_init(pool pool);
	106	void flow_builder_clear(struct flow_builder *fb);
	107	void flow_builder_set_type(struct flow_builder *fb, enum flow_type p);
	108	int flow_builder4_add_pfx(struct flow_builder fb, const net_addr_ip4 n4);
	109	int flow_builder6_add_pfx(struct flow_builder fb, const net_addr_ip6 n6, u32 offset);
	110	int flow_builder_add_op_val(struct flow_builder *fb, byte op, u32 value);
	111	int flow_builder_add_val_mask(struct flow_builder *fb, byte op, u32 value, u32 mask);
	112	net_addr_flow4 flow_builder4_finalize(struct flow_builder fb, linpool *lpool);
	113	net_addr_flow6 flow_builder6_finalize(struct flow_builder fb, linpool *lpool);
	114
	115
	116	/*
	117	* Validation
	118	*/
	119
	120	/* Results of validation Flow specification */
	121	enum flow_validated_state {
	122	FLOW_ST_UNKNOWN_COMPONENT,
	123	FLOW_ST_VALID,
	124	FLOW_ST_NOT_COMPLETE,
	125	FLOW_ST_EXCEED_MAX_PREFIX_LENGTH,
126	FLOW_ST_EXCEED_MAX_PREFIX_OFFSET,
127	FLOW_ST_EXCEED_MAX_VALUE_LENGTH,
128	FLOW_ST_BAD_TYPE_ORDER,
129	FLOW_ST_AND_BIT_SHOULD_BE_UNSET,
130	FLOW_ST_ZERO_BIT_SHOULD_BE_UNSED,
131	FLOW_ST_DEST_PREFIX_REQUIRED,
5ca4bd5d	132	FLOW_ST_INVALID_TCP_FLAGS,
77234bbb OZ	133	FLOW_ST_CANNOT_USE_DONT_FRAGMENT
	134	};
	135
	136	const char *flow_validated_state_str(enum flow_validated_state code);
	137	enum flow_validated_state flow4_validate(const byte *nlri, uint len);
	138	enum flow_validated_state flow6_validate(const byte *nlri, uint len);
	139	void flow_check_cf_value_length(struct flow_builder *fb, u32 expr);
	140	void flow_check_cf_bmk_values(struct flow_builder *fb, u8 neg, u32 val, u32 mask);
	141	void flow4_validate_cf(net_addr_flow4 *f);
	142	void flow6_validate_cf(net_addr_flow6 *f);
	143
	144
	145	/*
	146	* Net Formatting
	147	*/
	148
eeba61cc OZ	149	uint flow4_net_format(char buf, uint blen, const net_addr_flow4 f);
eeba61cc OZ	150	uint flow6_net_format(char buf, uint blen, const net_addr_flow6 f);
77234bbb OZ	151
77234bbb OZ	152	#endif /* _BIRD_FLOWSPEC_H_ */