[mirror_frr.git] / lib / mpls.h

/*
 * MPLS definitions
 * Copyright 2015 Cumulus Networks, Inc.
 *
 * This file is part of GNU Zebra.
 *
 * GNU Zebra is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published
 * by the Free Software Foundation; either version 2, or (at your
 * option) any later version.
 *
 * GNU Zebra is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; see the file COPYING; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
 */

#ifndef _QUAGGA_MPLS_H
#define _QUAGGA_MPLS_H

#include <arpa/inet.h>

/* Well-known MPLS label values (RFC 3032 etc). */
#define MPLS_V4_EXP_NULL_LABEL             0
#define MPLS_RA_LABEL                      1
#define MPLS_V6_EXP_NULL_LABEL             2
#define MPLS_IMP_NULL_LABEL                3
#define MPLS_ENTROPY_LABEL_INDICATOR       7
#define MPLS_GAL_LABEL                     13
#define MPLS_OAM_ALERT_LABEL               14
#define MPLS_EXTENSION_LABEL               15

/* Minimum and maximum label values */
#define MPLS_MIN_RESERVED_LABEL            0
#define MPLS_MAX_RESERVED_LABEL            15
#define MPLS_MIN_UNRESERVED_LABEL          16
#define MPLS_MAX_UNRESERVED_LABEL          1048575

/* Default min and max SRGB label range */
/* Even if the SRGB allows to manage different Label space between routers,
 * if an operator want to use the same SRGB for all its router, we must fix
 * a common range. However, Cisco start its SRGB at 16000 and Juniper ends
 * its SRGB at 16384 for OSPF. Thus, by fixing the minimum SRGB label to
 * 8000 we could deal with both Cisco and Juniper.
 */
#define MPLS_DEFAULT_MIN_SRGB_LABEL        8000
#define MPLS_DEFAULT_MAX_SRGB_LABEL        50000
#define MPLS_DEFAULT_MIN_SRGB_SIZE         5000
#define MPLS_DEFAULT_MAX_SRGB_SIZE         20000

/* Maximum # labels that can be pushed. */
#define MPLS_MAX_LABELS                    16

#define IS_MPLS_RESERVED_LABEL(label)                                          \
	(label >= MPLS_MIN_RESERVED_LABEL && label <= MPLS_MAX_RESERVED_LABEL)

#define IS_MPLS_UNRESERVED_LABEL(label)                                        \
	(label >= MPLS_MIN_UNRESERVED_LABEL                                    \
	 && label <= MPLS_MAX_UNRESERVED_LABEL)

/* Definitions for a MPLS label stack entry (RFC 3032). This encodes the
 * label, EXP, BOS and TTL fields.
 */
typedef unsigned int mpls_lse_t;

#define MPLS_LS_LABEL_MASK             0xFFFFF000
#define MPLS_LS_LABEL_SHIFT            12
#define MPLS_LS_EXP_MASK               0x00000E00
#define MPLS_LS_EXP_SHIFT              9
#define MPLS_LS_S_MASK                 0x00000100
#define MPLS_LS_S_SHIFT                8
#define MPLS_LS_TTL_MASK               0x000000FF
#define MPLS_LS_TTL_SHIFT              0

#define MPLS_LABEL_VALUE(lse)                                                  \
	((lse & MPLS_LS_LABEL_MASK) >> MPLS_LS_LABEL_SHIFT)
#define MPLS_LABEL_EXP(lse) ((lse & MPLS_LS_EXP_MASK) >> MPLS_LS_EXP_SHIFT)
#define MPLS_LABEL_BOS(lse) ((lse & MPLS_LS_S_MASK) >> MPLS_LS_S_SHIFT)
#define MPLS_LABEL_TTL(lse) ((lse & MPLS_LS_TTL_MASK) >> MPLS_LS_TTL_SHIFT)

#define IS_MPLS_LABEL_BOS(ls)          (MPLS_LABEL_BOS(ls) == 1)

#define MPLS_LABEL_LEN_BITS            20

/* MPLS label value as a 32-bit (mostly we only care about the label value). */
typedef unsigned int mpls_label_t;

struct mpls_label_stack {
	uint8_t num_labels;
	uint8_t reserved[3];
	mpls_label_t label[0]; /* 1 or more labels */
};

/* The MPLS explicit-null label is 0 which means when you memset a mpls_label_t
 * to zero you have set that variable to explicit-null which was probably not
 * your intent. The work-around is to use one bit to indicate if the
 * mpls_label_t has been set by the user. MPLS_INVALID_LABEL has this bit clear
 * so that we can use MPLS_INVALID_LABEL to initialize mpls_label_t variables.
 */
#define MPLS_INVALID_LABEL                 0xFFFDFFFF

/* LSP types. */
enum lsp_types_t {
	ZEBRA_LSP_NONE = 0,   /* No LSP. */
	ZEBRA_LSP_STATIC = 1, /* Static LSP. */
	ZEBRA_LSP_LDP = 2,    /* LDP LSP. */
	ZEBRA_LSP_BGP = 3,    /* BGP LSP. */
	ZEBRA_LSP_SR = 4      /* Segment Routing LSP. */
};

/* Functions for basic label operations. */

/* Encode a label stack entry from fields; convert to network byte-order as
 * the Netlink interface expects MPLS labels to be in this format.
 */
static inline mpls_lse_t mpls_lse_encode(mpls_label_t label, u_int32_t ttl,
					 u_int32_t exp, u_int32_t bos)
{
	mpls_lse_t lse;
	lse = htonl((label << MPLS_LS_LABEL_SHIFT) | (exp << MPLS_LS_EXP_SHIFT)
		    | (bos ? (1 << MPLS_LS_S_SHIFT) : 0)
		    | (ttl << MPLS_LS_TTL_SHIFT));
	return lse;
}

/* Extract the fields from a label stack entry after converting to host-byte
 * order. This is expected to be called only for messages received over the
 * Netlink interface.
 */
static inline void mpls_lse_decode(mpls_lse_t lse, mpls_label_t *label,
				   u_int32_t *ttl, u_int32_t *exp,
				   u_int32_t *bos)
{
	mpls_lse_t local_lse;

	local_lse = ntohl(lse);
	*label = MPLS_LABEL_VALUE(local_lse);
	*exp = MPLS_LABEL_EXP(local_lse);
	*bos = MPLS_LABEL_BOS(local_lse);
	*ttl = MPLS_LABEL_TTL(local_lse);
}

/* Invalid label index value (when used with BGP Prefix-SID). Should
 * match the BGP definition.
 */
#define MPLS_INVALID_LABEL_INDEX   0xFFFFFFFF

/* Printable string for labels (with consideration for reserved values). */
static inline char *label2str(mpls_label_t label, char *buf, size_t len)
{
	switch (label) {
	case MPLS_V4_EXP_NULL_LABEL:
		strlcpy(buf, "IPv4 Explicit Null", len);
		return (buf);
	case MPLS_RA_LABEL:
		strlcpy(buf, "Router Alert", len);
		return (buf);
	case MPLS_V6_EXP_NULL_LABEL:
		strlcpy(buf, "IPv6 Explict Null", len);
		return (buf);
	case MPLS_IMP_NULL_LABEL:
		strlcpy(buf, "implicit-null", len);
		return (buf);
	case MPLS_ENTROPY_LABEL_INDICATOR:
		strlcpy(buf, "Entropy Label Indicator", len);
		return (buf);
	case MPLS_GAL_LABEL:
		strlcpy(buf, "Generic Associated Channel", len);
		return (buf);
	case MPLS_OAM_ALERT_LABEL:
		strlcpy(buf, "OAM Alert", len);
		return (buf);
	case MPLS_EXTENSION_LABEL:
		strlcpy(buf, "Extension", len);
		return (buf);
	default:
		if (label < 16)
			snprintf(buf, len, "Reserved (%u)", label);
		else
			snprintf(buf, len, "%u", label);
		return (buf);
	}
}

/* constants used by ldpd */
#define MPLS_LABEL_IPV4NULL	0               /* IPv4 Explicit NULL Label */
#define MPLS_LABEL_RTALERT	1               /* Router Alert Label       */
#define MPLS_LABEL_IPV6NULL	2               /* IPv6 Explicit NULL Label */
#define MPLS_LABEL_IMPLNULL	3               /* Implicit NULL Label      */
	/*      MPLS_LABEL_RESERVED	4-15 */ /* Values 4-15 are reserved */
#define MPLS_LABEL_RESERVED_MAX 15
#define MPLS_LABEL_MAX		((1 << 20) - 1)

#endif
Commit	Line	Data
50f34207	1	/*
	2	* MPLS definitions
	3	* Copyright 2015 Cumulus Networks, Inc.
	4	*
	5	* This file is part of GNU Zebra.
	6	*
	7	* GNU Zebra is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License as published
	9	* by the Free Software Foundation; either version 2, or (at your
	10	* option) any later version.
	11	*
	12	* GNU Zebra is distributed in the hope that it will be useful, but
	13	* WITHOUT ANY WARRANTY; without even the implied warranty of
	14	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	15	* General Public License for more details.
	16	*
896014f4 DL	17	* You should have received a copy of the GNU General Public License along
	18	* with this program; see the file COPYING; if not, write to the Free Software
	19	* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
50f34207	20	*/
	21
	22	#ifndef _QUAGGA_MPLS_H
	23	#define _QUAGGA_MPLS_H
	24
fea12efb	25	#include <arpa/inet.h>
fea12efb	26
50f34207	27	/* Well-known MPLS label values (RFC 3032 etc). */
	28	#define MPLS_V4_EXP_NULL_LABEL 0
	29	#define MPLS_RA_LABEL 1
	30	#define MPLS_V6_EXP_NULL_LABEL 2
	31	#define MPLS_IMP_NULL_LABEL 3
	32	#define MPLS_ENTROPY_LABEL_INDICATOR 7
	33	#define MPLS_GAL_LABEL 13
	34	#define MPLS_OAM_ALERT_LABEL 14
	35	#define MPLS_EXTENSION_LABEL 15
	36
	37	/* Minimum and maximum label values */
	38	#define MPLS_MIN_RESERVED_LABEL 0
	39	#define MPLS_MAX_RESERVED_LABEL 15
	40	#define MPLS_MIN_UNRESERVED_LABEL 16
	41	#define MPLS_MAX_UNRESERVED_LABEL 1048575
	42
12929668	43	/* Default min and max SRGB label range */
7726c479 OD	44	/* Even if the SRGB allows to manage different Label space between routers,
	45	* if an operator want to use the same SRGB for all its router, we must fix
	46	* a common range. However, Cisco start its SRGB at 16000 and Juniper ends
	47	* its SRGB at 16384 for OSPF. Thus, by fixing the minimum SRGB label to
	48	* 8000 we could deal with both Cisco and Juniper.
	49	*/
	50	#define MPLS_DEFAULT_MIN_SRGB_LABEL 8000
cf9b9f77 OD	51	#define MPLS_DEFAULT_MAX_SRGB_LABEL 50000
	52	#define MPLS_DEFAULT_MIN_SRGB_SIZE 5000
	53	#define MPLS_DEFAULT_MAX_SRGB_SIZE 20000
12929668	54
52dd3aa4 RW	55	/* Maximum # labels that can be pushed. */
	56	#define MPLS_MAX_LABELS 16
	57
d62a17ae	58	#define IS_MPLS_RESERVED_LABEL(label) \
d62a17ae	59	(label >= MPLS_MIN_RESERVED_LABEL && label <= MPLS_MAX_RESERVED_LABEL)
50f34207	60
d62a17ae	61	#define IS_MPLS_UNRESERVED_LABEL(label) \
	62	(label >= MPLS_MIN_UNRESERVED_LABEL \
	63	&& label <= MPLS_MAX_UNRESERVED_LABEL)
50f34207	64
	65	/* Definitions for a MPLS label stack entry (RFC 3032). This encodes the
	66	* label, EXP, BOS and TTL fields.
	67	*/
	68	typedef unsigned int mpls_lse_t;
	69
	70	#define MPLS_LS_LABEL_MASK 0xFFFFF000
	71	#define MPLS_LS_LABEL_SHIFT 12
	72	#define MPLS_LS_EXP_MASK 0x00000E00
	73	#define MPLS_LS_EXP_SHIFT 9
	74	#define MPLS_LS_S_MASK 0x00000100
	75	#define MPLS_LS_S_SHIFT 8
	76	#define MPLS_LS_TTL_MASK 0x000000FF
	77	#define MPLS_LS_TTL_SHIFT 0
	78
d62a17ae	79	#define MPLS_LABEL_VALUE(lse) \
	80	((lse & MPLS_LS_LABEL_MASK) >> MPLS_LS_LABEL_SHIFT)
	81	#define MPLS_LABEL_EXP(lse) ((lse & MPLS_LS_EXP_MASK) >> MPLS_LS_EXP_SHIFT)
	82	#define MPLS_LABEL_BOS(lse) ((lse & MPLS_LS_S_MASK) >> MPLS_LS_S_SHIFT)
	83	#define MPLS_LABEL_TTL(lse) ((lse & MPLS_LS_TTL_MASK) >> MPLS_LS_TTL_SHIFT)
50f34207	84
	85	#define IS_MPLS_LABEL_BOS(ls) (MPLS_LABEL_BOS(ls) == 1)
	86
	87	#define MPLS_LABEL_LEN_BITS 20
	88
	89	/* MPLS label value as a 32-bit (mostly we only care about the label value). */
	90	typedef unsigned int mpls_label_t;
	91
8ecdb26e DS	92	struct mpls_label_stack {
	93	uint8_t num_labels;
	94	uint8_t reserved[3];
	95	mpls_label_t label[0]; /* 1 or more labels */
	96	};
	97
9bedbb1e DW	98	/* The MPLS explicit-null label is 0 which means when you memset a mpls_label_t
	99	* to zero you have set that variable to explicit-null which was probably not
	100	* your intent. The work-around is to use one bit to indicate if the
	101	* mpls_label_t has been set by the user. MPLS_INVALID_LABEL has this bit clear
	102	* so that we can use MPLS_INVALID_LABEL to initialize mpls_label_t variables.
	103	*/
	104	#define MPLS_INVALID_LABEL 0xFFFDFFFF
50f34207	105
ce549947	106	/* LSP types. */
d62a17ae	107	enum lsp_types_t {
	108	ZEBRA_LSP_NONE = 0, /* No LSP. */
	109	ZEBRA_LSP_STATIC = 1, /* Static LSP. */
	110	ZEBRA_LSP_LDP = 2, /* LDP LSP. */
cf9b9f77 OD	111	ZEBRA_LSP_BGP = 3, /* BGP LSP. */
cf9b9f77 OD	112	ZEBRA_LSP_SR = 4 /* Segment Routing LSP. */
ce549947 RW	113	};
ce549947 RW	114
50f34207	115	/* Functions for basic label operations. */
	116
	117	/* Encode a label stack entry from fields; convert to network byte-order as
	118	* the Netlink interface expects MPLS labels to be in this format.
	119	*/
d62a17ae	120	static inline mpls_lse_t mpls_lse_encode(mpls_label_t label, u_int32_t ttl,
d62a17ae	121	u_int32_t exp, u_int32_t bos)
50f34207	122	{
d62a17ae	123	mpls_lse_t lse;
	124	lse = htonl((label << MPLS_LS_LABEL_SHIFT) \| (exp << MPLS_LS_EXP_SHIFT)
	125	\| (bos ? (1 << MPLS_LS_S_SHIFT) : 0)
	126	\| (ttl << MPLS_LS_TTL_SHIFT));
	127	return lse;
50f34207	128	}
	129
	130	/* Extract the fields from a label stack entry after converting to host-byte
	131	* order. This is expected to be called only for messages received over the
	132	* Netlink interface.
	133	*/
d62a17ae	134	static inline void mpls_lse_decode(mpls_lse_t lse, mpls_label_t *label,
	135	u_int32_t ttl, u_int32_t exp,
	136	u_int32_t *bos)
50f34207	137	{
d62a17ae	138	mpls_lse_t local_lse;
50f34207	139
d62a17ae	140	local_lse = ntohl(lse);
	141	*label = MPLS_LABEL_VALUE(local_lse);
	142	*exp = MPLS_LABEL_EXP(local_lse);
	143	*bos = MPLS_LABEL_BOS(local_lse);
	144	*ttl = MPLS_LABEL_TTL(local_lse);
50f34207	145	}
50f34207	146
28d58fd7 VV	147	/* Invalid label index value (when used with BGP Prefix-SID). Should
	148	* match the BGP definition.
	149	*/
	150	#define MPLS_INVALID_LABEL_INDEX 0xFFFFFFFF
	151
50f34207	152	/* Printable string for labels (with consideration for reserved values). */
d62a17ae	153	static inline char label2str(mpls_label_t label, char buf, size_t len)
50f34207	154	{
d62a17ae	155	switch (label) {
	156	case MPLS_V4_EXP_NULL_LABEL:
	157	strlcpy(buf, "IPv4 Explicit Null", len);
	158	return (buf);
	159	case MPLS_RA_LABEL:
	160	strlcpy(buf, "Router Alert", len);
	161	return (buf);
	162	case MPLS_V6_EXP_NULL_LABEL:
	163	strlcpy(buf, "IPv6 Explict Null", len);
	164	return (buf);
	165	case MPLS_IMP_NULL_LABEL:
	166	strlcpy(buf, "implicit-null", len);
	167	return (buf);
	168	case MPLS_ENTROPY_LABEL_INDICATOR:
	169	strlcpy(buf, "Entropy Label Indicator", len);
	170	return (buf);
	171	case MPLS_GAL_LABEL:
	172	strlcpy(buf, "Generic Associated Channel", len);
	173	return (buf);
	174	case MPLS_OAM_ALERT_LABEL:
	175	strlcpy(buf, "OAM Alert", len);
	176	return (buf);
	177	case MPLS_EXTENSION_LABEL:
	178	strlcpy(buf, "Extension", len);
	179	return (buf);
	180	default:
	181	if (label < 16)
	182	snprintf(buf, len, "Reserved (%u)", label);
	183	else
	184	snprintf(buf, len, "%u", label);
	185	return (buf);
	186	}
50f34207	187	}
50f34207	188
eac6e3f0 RW	189	/* constants used by ldpd */
	190	#define MPLS_LABEL_IPV4NULL 0 /* IPv4 Explicit NULL Label */
	191	#define MPLS_LABEL_RTALERT 1 /* Router Alert Label */
	192	#define MPLS_LABEL_IPV6NULL 2 /* IPv6 Explicit NULL Label */
	193	#define MPLS_LABEL_IMPLNULL 3 /* Implicit NULL Label */
9d303b37	194	/* MPLS_LABEL_RESERVED 4-15 / / Values 4-15 are reserved */
eac6e3f0 RW	195	#define MPLS_LABEL_RESERVED_MAX 15
	196	#define MPLS_LABEL_MAX ((1 << 20) - 1)
	197
50f34207	198	#endif