[mirror_ubuntu-bionic-kernel.git] / net / mpls / internal.h

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef MPLS_INTERNAL_H
#define MPLS_INTERNAL_H
#include <net/mpls.h>

/* put a reasonable limit on the number of labels
 * we will accept from userspace
 */
#define MAX_NEW_LABELS 30

struct mpls_entry_decoded {
	u32 label;
	u8 ttl;
	u8 tc;
	u8 bos;
};

struct mpls_pcpu_stats {
	struct mpls_link_stats	stats;
	struct u64_stats_sync	syncp;
};

struct mpls_dev {
	int				input_enabled;
	struct net_device		*dev;
	struct mpls_pcpu_stats __percpu	*stats;

	struct ctl_table_header		*sysctl;
	struct rcu_head			rcu;
};

#if BITS_PER_LONG == 32

#define MPLS_INC_STATS_LEN(mdev, len, pkts_field, bytes_field)		\
	do {								\
		__typeof__(*(mdev)->stats) *ptr =			\
			raw_cpu_ptr((mdev)->stats);			\
		local_bh_disable();					\
		u64_stats_update_begin(&ptr->syncp);			\
		ptr->stats.pkts_field++;				\
		ptr->stats.bytes_field += (len);			\
		u64_stats_update_end(&ptr->syncp);			\
		local_bh_enable();					\
	} while (0)

#define MPLS_INC_STATS(mdev, field)					\
	do {								\
		__typeof__(*(mdev)->stats) *ptr =			\
			raw_cpu_ptr((mdev)->stats);			\
		local_bh_disable();					\
		u64_stats_update_begin(&ptr->syncp);			\
		ptr->stats.field++;					\
		u64_stats_update_end(&ptr->syncp);			\
		local_bh_enable();					\
	} while (0)

#else

#define MPLS_INC_STATS_LEN(mdev, len, pkts_field, bytes_field)		\
	do {								\
		this_cpu_inc((mdev)->stats->stats.pkts_field);		\
		this_cpu_add((mdev)->stats->stats.bytes_field, (len));	\
	} while (0)

#define MPLS_INC_STATS(mdev, field)			\
	this_cpu_inc((mdev)->stats->stats.field)

#endif

struct sk_buff;

#define LABEL_NOT_SPECIFIED (1 << 20)

/* This maximum ha length copied from the definition of struct neighbour */
#define VIA_ALEN_ALIGN sizeof(unsigned long)
#define MAX_VIA_ALEN (ALIGN(MAX_ADDR_LEN, VIA_ALEN_ALIGN))

enum mpls_payload_type {
	MPT_UNSPEC, /* IPv4 or IPv6 */
	MPT_IPV4 = 4,
	MPT_IPV6 = 6,

	/* Other types not implemented:
	 *  - Pseudo-wire with or without control word (RFC4385)
	 *  - GAL (RFC5586)
	 */
};

struct mpls_nh { /* next hop label forwarding entry */
	struct net_device __rcu *nh_dev;

	/* nh_flags is accessed under RCU in the packet path; it is
	 * modified handling netdev events with rtnl lock held
	 */
	unsigned int		nh_flags;
	u8			nh_labels;
	u8			nh_via_alen;
	u8			nh_via_table;
	u8			nh_reserved1;

	u32			nh_label[0];
};

/* offset of via from beginning of mpls_nh */
#define MPLS_NH_VIA_OFF(num_labels) \
		ALIGN(sizeof(struct mpls_nh) + (num_labels) * sizeof(u32), \
		      VIA_ALEN_ALIGN)

/* all nexthops within a route have the same size based on the
 * max number of labels and max via length across all nexthops
 */
#define MPLS_NH_SIZE(num_labels, max_via_alen)		\
		(MPLS_NH_VIA_OFF((num_labels)) +	\
		ALIGN((max_via_alen), VIA_ALEN_ALIGN))

enum mpls_ttl_propagation {
	MPLS_TTL_PROP_DEFAULT,
	MPLS_TTL_PROP_ENABLED,
	MPLS_TTL_PROP_DISABLED,
};

/* The route, nexthops and vias are stored together in the same memory
 * block:
 *
 * +----------------------+
 * | mpls_route           |
 * +----------------------+
 * | mpls_nh 0            |
 * +----------------------+
 * | alignment padding    |   4 bytes for odd number of labels
 * +----------------------+
 * | via[rt_max_alen] 0   |
 * +----------------------+
 * | alignment padding    |   via's aligned on sizeof(unsigned long)
 * +----------------------+
 * | ...                  |
 * +----------------------+
 * | mpls_nh n-1          |
 * +----------------------+
 * | via[rt_max_alen] n-1 |
 * +----------------------+
 */
struct mpls_route { /* next hop label forwarding entry */
	struct rcu_head		rt_rcu;
	u8			rt_protocol;
	u8			rt_payload_type;
	u8			rt_max_alen;
	u8			rt_ttl_propagate;
	u8			rt_nhn;
	/* rt_nhn_alive is accessed under RCU in the packet path; it
	 * is modified handling netdev events with rtnl lock held
	 */
	u8			rt_nhn_alive;
	u8			rt_nh_size;
	u8			rt_via_offset;
	u8			rt_reserved1;
	struct mpls_nh		rt_nh[0];
};

#define for_nexthops(rt) {						\
	int nhsel; struct mpls_nh *nh;  u8 *__nh;			\
	for (nhsel = 0, nh = (rt)->rt_nh, __nh = (u8 *)((rt)->rt_nh);	\
	     nhsel < (rt)->rt_nhn;					\
	     __nh += rt->rt_nh_size, nh = (struct mpls_nh *)__nh, nhsel++)

#define change_nexthops(rt) {						\
	int nhsel; struct mpls_nh *nh; u8 *__nh;			\
	for (nhsel = 0, nh = (struct mpls_nh *)((rt)->rt_nh),		\
			__nh = (u8 *)((rt)->rt_nh);			\
	     nhsel < (rt)->rt_nhn;					\
	     __nh += rt->rt_nh_size, nh = (struct mpls_nh *)__nh, nhsel++)

#define endfor_nexthops(rt) }

static inline struct mpls_shim_hdr mpls_entry_encode(u32 label, unsigned ttl, unsigned tc, bool bos)
{
	struct mpls_shim_hdr result;
	result.label_stack_entry =
		cpu_to_be32((label << MPLS_LS_LABEL_SHIFT) |
			    (tc << MPLS_LS_TC_SHIFT) |
			    (bos ? (1 << MPLS_LS_S_SHIFT) : 0) |
			    (ttl << MPLS_LS_TTL_SHIFT));
	return result;
}

static inline struct mpls_entry_decoded mpls_entry_decode(struct mpls_shim_hdr *hdr)
{
	struct mpls_entry_decoded result;
	unsigned entry = be32_to_cpu(hdr->label_stack_entry);

	result.label = (entry & MPLS_LS_LABEL_MASK) >> MPLS_LS_LABEL_SHIFT;
	result.ttl = (entry & MPLS_LS_TTL_MASK) >> MPLS_LS_TTL_SHIFT;
	result.tc =  (entry & MPLS_LS_TC_MASK) >> MPLS_LS_TC_SHIFT;
	result.bos = (entry & MPLS_LS_S_MASK) >> MPLS_LS_S_SHIFT;

	return result;
}

static inline struct mpls_dev *mpls_dev_get(const struct net_device *dev)
{
	return rcu_dereference_rtnl(dev->mpls_ptr);
}

int nla_put_labels(struct sk_buff *skb, int attrtype,  u8 labels,
		   const u32 label[]);
int nla_get_labels(const struct nlattr *nla, u8 max_labels, u8 *labels,
		   u32 label[], struct netlink_ext_ack *extack);
bool mpls_output_possible(const struct net_device *dev);
unsigned int mpls_dev_mtu(const struct net_device *dev);
bool mpls_pkt_too_big(const struct sk_buff *skb, unsigned int mtu);
void mpls_stats_inc_outucastpkts(struct net_device *dev,
				 const struct sk_buff *skb);

#endif /* MPLS_INTERNAL_H */
Commit	Line	Data
b2441318	1	/* SPDX-License-Identifier: GPL-2.0 */
0189197f EB	2	#ifndef MPLS_INTERNAL_H
0189197f EB	3	#define MPLS_INTERNAL_H
9095e10e	4	#include <net/mpls.h>
0189197f	5
1511009c DA	6	/* put a reasonable limit on the number of labels
	7	* we will accept from userspace
	8	*/
	9	#define MAX_NEW_LABELS 30
	10
0189197f EB	11	struct mpls_entry_decoded {
	12	u32 label;
	13	u8 ttl;
	14	u8 tc;
	15	u8 bos;
	16	};
	17
27d69105 RS	18	struct mpls_pcpu_stats {
	19	struct mpls_link_stats stats;
	20	struct u64_stats_sync syncp;
	21	};
	22
03c57747	23	struct mpls_dev {
27d69105	24	int input_enabled;
24045a03	25	struct net_device *dev;
27d69105 RS	26	struct mpls_pcpu_stats __percpu *stats;
	27
	28	struct ctl_table_header *sysctl;
	29	struct rcu_head rcu;
03c57747 RS	30	};
03c57747 RS	31
27d69105 RS	32	#if BITS_PER_LONG == 32
	33
	34	#define MPLS_INC_STATS_LEN(mdev, len, pkts_field, bytes_field) \
	35	do { \
	36	__typeof__((mdev)->stats) ptr = \
	37	raw_cpu_ptr((mdev)->stats); \
	38	local_bh_disable(); \
	39	u64_stats_update_begin(&ptr->syncp); \
	40	ptr->stats.pkts_field++; \
	41	ptr->stats.bytes_field += (len); \
	42	u64_stats_update_end(&ptr->syncp); \
	43	local_bh_enable(); \
	44	} while (0)
	45
	46	#define MPLS_INC_STATS(mdev, field) \
	47	do { \
	48	__typeof__((mdev)->stats) ptr = \
	49	raw_cpu_ptr((mdev)->stats); \
	50	local_bh_disable(); \
	51	u64_stats_update_begin(&ptr->syncp); \
	52	ptr->stats.field++; \
	53	u64_stats_update_end(&ptr->syncp); \
	54	local_bh_enable(); \
	55	} while (0)
	56
	57	#else
	58
	59	#define MPLS_INC_STATS_LEN(mdev, len, pkts_field, bytes_field) \
	60	do { \
	61	this_cpu_inc((mdev)->stats->stats.pkts_field); \
	62	this_cpu_add((mdev)->stats->stats.bytes_field, (len)); \
	63	} while (0)
	64
	65	#define MPLS_INC_STATS(mdev, field) \
	66	this_cpu_inc((mdev)->stats->stats.field)
	67
	68	#endif
	69
0189197f EB	70	struct sk_buff;
0189197f EB	71
f8efb73c	72	#define LABEL_NOT_SPECIFIED (1 << 20)
f8efb73c RP	73
f8efb73c RP	74	/* This maximum ha length copied from the definition of struct neighbour */
cf4b24f0 RS	75	#define VIA_ALEN_ALIGN sizeof(unsigned long)
cf4b24f0 RS	76	#define MAX_VIA_ALEN (ALIGN(MAX_ADDR_LEN, VIA_ALEN_ALIGN))
f8efb73c RP	77
	78	enum mpls_payload_type {
	79	MPT_UNSPEC, /* IPv4 or IPv6 */
	80	MPT_IPV4 = 4,
	81	MPT_IPV6 = 6,
	82
	83	/* Other types not implemented:
	84	* - Pseudo-wire with or without control word (RFC4385)
	85	* - GAL (RFC5586)
	86	*/
	87	};
	88
	89	struct mpls_nh { /* next hop label forwarding entry */
	90	struct net_device __rcu *nh_dev;
39eb8cd1 DA	91
	92	/* nh_flags is accessed under RCU in the packet path; it is
	93	* modified handling netdev events with rtnl lock held
	94	*/
c89359a4	95	unsigned int nh_flags;
f8efb73c RP	96	u8 nh_labels;
	97	u8 nh_via_alen;
	98	u8 nh_via_table;
59b20966 DA	99	u8 nh_reserved1;
	100
	101	u32 nh_label[0];
f8efb73c RP	102	};
f8efb73c RP	103
59b20966 DA	104	/* offset of via from beginning of mpls_nh */
	105	#define MPLS_NH_VIA_OFF(num_labels) \
	106	ALIGN(sizeof(struct mpls_nh) + (num_labels) * sizeof(u32), \
	107	VIA_ALEN_ALIGN)
	108
	109	/* all nexthops within a route have the same size based on the
	110	* max number of labels and max via length across all nexthops
	111	*/
	112	#define MPLS_NH_SIZE(num_labels, max_via_alen) \
	113	(MPLS_NH_VIA_OFF((num_labels)) + \
	114	ALIGN((max_via_alen), VIA_ALEN_ALIGN))
	115
5b441ac8 RS	116	enum mpls_ttl_propagation {
	117	MPLS_TTL_PROP_DEFAULT,
	118	MPLS_TTL_PROP_ENABLED,
	119	MPLS_TTL_PROP_DISABLED,
	120	};
	121
cf4b24f0 RS	122	/* The route, nexthops and vias are stored together in the same memory
	123	* block:
	124	*
	125	* +----------------------+
	126	* \| mpls_route \|
	127	* +----------------------+
	128	* \| mpls_nh 0 \|
	129	* +----------------------+
59b20966	130	* \| alignment padding \| 4 bytes for odd number of labels
cf4b24f0 RS	131	* +----------------------+
	132	* \| via[rt_max_alen] 0 \|
	133	* +----------------------+
59b20966 DA	134	* \| alignment padding \| via's aligned on sizeof(unsigned long)
59b20966 DA	135	* +----------------------+
cf4b24f0 RS	136	* \| ... \|
cf4b24f0 RS	137	* +----------------------+
59b20966 DA	138	* \| mpls_nh n-1 \|
59b20966 DA	139	* +----------------------+
cf4b24f0 RS	140	* \| via[rt_max_alen] n-1 \|
	141	* +----------------------+
	142	*/
f8efb73c RP	143	struct mpls_route { /* next hop label forwarding entry */
	144	struct rcu_head rt_rcu;
	145	u8 rt_protocol;
	146	u8 rt_payload_type;
cf4b24f0	147	u8 rt_max_alen;
5b441ac8	148	u8 rt_ttl_propagate;
77ef013a	149	u8 rt_nhn;
39eb8cd1 DA	150	/* rt_nhn_alive is accessed under RCU in the packet path; it
	151	* is modified handling netdev events with rtnl lock held
	152	*/
77ef013a	153	u8 rt_nhn_alive;
59b20966 DA	154	u8 rt_nh_size;
	155	u8 rt_via_offset;
	156	u8 rt_reserved1;
f8efb73c RP	157	struct mpls_nh rt_nh[0];
	158	};
	159
	160	#define for_nexthops(rt) { \
59b20966 DA	161	int nhsel; struct mpls_nh nh; u8 __nh; \
59b20966 DA	162	for (nhsel = 0, nh = (rt)->rt_nh, __nh = (u8 *)((rt)->rt_nh); \
f8efb73c	163	nhsel < (rt)->rt_nhn; \
59b20966	164	__nh += rt->rt_nh_size, nh = (struct mpls_nh *)__nh, nhsel++)
f8efb73c RP	165
f8efb73c RP	166	#define change_nexthops(rt) { \
59b20966 DA	167	int nhsel; struct mpls_nh nh; u8 __nh; \
	168	for (nhsel = 0, nh = (struct mpls_nh *)((rt)->rt_nh), \
	169	__nh = (u8 *)((rt)->rt_nh); \
f8efb73c	170	nhsel < (rt)->rt_nhn; \
59b20966	171	__nh += rt->rt_nh_size, nh = (struct mpls_nh *)__nh, nhsel++)
f8efb73c RP	172
	173	#define endfor_nexthops(rt) }
	174
0189197f EB	175	static inline struct mpls_shim_hdr mpls_entry_encode(u32 label, unsigned ttl, unsigned tc, bool bos)
	176	{
	177	struct mpls_shim_hdr result;
	178	result.label_stack_entry =
	179	cpu_to_be32((label << MPLS_LS_LABEL_SHIFT) \|
	180	(tc << MPLS_LS_TC_SHIFT) \|
	181	(bos ? (1 << MPLS_LS_S_SHIFT) : 0) \|
	182	(ttl << MPLS_LS_TTL_SHIFT));
	183	return result;
	184	}
	185
	186	static inline struct mpls_entry_decoded mpls_entry_decode(struct mpls_shim_hdr *hdr)
	187	{
	188	struct mpls_entry_decoded result;
	189	unsigned entry = be32_to_cpu(hdr->label_stack_entry);
	190
	191	result.label = (entry & MPLS_LS_LABEL_MASK) >> MPLS_LS_LABEL_SHIFT;
	192	result.ttl = (entry & MPLS_LS_TTL_MASK) >> MPLS_LS_TTL_SHIFT;
	193	result.tc = (entry & MPLS_LS_TC_MASK) >> MPLS_LS_TC_SHIFT;
	194	result.bos = (entry & MPLS_LS_S_MASK) >> MPLS_LS_S_SHIFT;
	195
	196	return result;
	197	}
	198
27d69105 RS	199	static inline struct mpls_dev mpls_dev_get(const struct net_device dev)
	200	{
	201	return rcu_dereference_rtnl(dev->mpls_ptr);
	202	}
	203
face0188 RP	204	int nla_put_labels(struct sk_buff *skb, int attrtype, u8 labels,
face0188 RP	205	const u32 label[]);
a4ac8c98	206	int nla_get_labels(const struct nlattr nla, u8 max_labels, u8 labels,
a1f10abe	207	u32 label[], struct netlink_ext_ack *extack);
face0188 RP	208	bool mpls_output_possible(const struct net_device *dev);
	209	unsigned int mpls_dev_mtu(const struct net_device *dev);
	210	bool mpls_pkt_too_big(const struct sk_buff *skb, unsigned int mtu);
27d69105 RS	211	void mpls_stats_inc_outucastpkts(struct net_device *dev,
27d69105 RS	212	const struct sk_buff *skb);
966bae33	213
0189197f	214	#endif /* MPLS_INTERNAL_H */