diff options
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/netdevice.h | 4 | ||||
| -rw-r--r-- | include/linux/socket.h | 6 | ||||
| -rw-r--r-- | include/net/mctp.h | 231 | ||||
| -rw-r--r-- | include/net/mctpdevice.h | 36 | ||||
| -rw-r--r-- | include/net/net_namespace.h | 4 | ||||
| -rw-r--r-- | include/net/netns/mctp.h | 36 | ||||
| -rw-r--r-- | include/uapi/linux/if_arp.h | 1 | ||||
| -rw-r--r-- | include/uapi/linux/if_ether.h | 3 | ||||
| -rw-r--r-- | include/uapi/linux/if_link.h | 10 | ||||
| -rw-r--r-- | include/uapi/linux/mctp.h | 36 |
10 files changed, 366 insertions, 1 deletions
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 226bbee06730..d63a94ecbf3b 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -1823,6 +1823,7 @@ enum netdev_ml_priv_type { * @ieee802154_ptr: IEEE 802.15.4 low-rate Wireless Personal Area Network * device struct * @mpls_ptr: mpls_dev struct pointer + * @mctp_ptr: MCTP specific data * * @dev_addr: Hw address (before bcast, * because most packets are unicast) @@ -2110,6 +2111,9 @@ struct net_device { #if IS_ENABLED(CONFIG_MPLS_ROUTING) struct mpls_dev __rcu *mpls_ptr; #endif +#if IS_ENABLED(CONFIG_MCTP) + struct mctp_dev __rcu *mctp_ptr; +#endif /* * Cache lines mostly used on receive path (including eth_type_trans()) diff --git a/include/linux/socket.h b/include/linux/socket.h index 0d8e3dcb7f88..fd9ce51582d8 100644 --- a/include/linux/socket.h +++ b/include/linux/socket.h @@ -223,8 +223,11 @@ struct ucred { * reuses AF_INET address family */ #define AF_XDP 44 /* XDP sockets */ +#define AF_MCTP 45 /* Management component + * transport protocol + */ -#define AF_MAX 45 /* For now.. */ +#define AF_MAX 46 /* For now.. */ /* Protocol families, same as address families. */ #define PF_UNSPEC AF_UNSPEC @@ -274,6 +277,7 @@ struct ucred { #define PF_QIPCRTR AF_QIPCRTR #define PF_SMC AF_SMC #define PF_XDP AF_XDP +#define PF_MCTP AF_MCTP #define PF_MAX AF_MAX /* Maximum queue length specifiable by listen. */ diff --git a/include/net/mctp.h b/include/net/mctp.h new file mode 100644 index 000000000000..54bbe042c973 --- /dev/null +++ b/include/net/mctp.h @@ -0,0 +1,231 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Management Component Transport Protocol (MCTP) + * + * Copyright (c) 2021 Code Construct + * Copyright (c) 2021 Google + */ + +#ifndef __NET_MCTP_H +#define __NET_MCTP_H + +#include <linux/bits.h> +#include <linux/mctp.h> +#include <net/net_namespace.h> +#include <net/sock.h> + +/* MCTP packet definitions */ +struct mctp_hdr { + u8 ver; + u8 dest; + u8 src; + u8 flags_seq_tag; +}; + +#define MCTP_VER_MIN 1 +#define MCTP_VER_MAX 1 + +/* Definitions for flags_seq_tag field */ +#define MCTP_HDR_FLAG_SOM BIT(7) +#define MCTP_HDR_FLAG_EOM BIT(6) +#define MCTP_HDR_FLAG_TO BIT(3) +#define MCTP_HDR_FLAGS GENMASK(5, 3) +#define MCTP_HDR_SEQ_SHIFT 4 +#define MCTP_HDR_SEQ_MASK GENMASK(1, 0) +#define MCTP_HDR_TAG_SHIFT 0 +#define MCTP_HDR_TAG_MASK GENMASK(2, 0) + +#define MCTP_HEADER_MAXLEN 4 + +#define MCTP_INITIAL_DEFAULT_NET 1 + +static inline bool mctp_address_ok(mctp_eid_t eid) +{ + return eid >= 8 && eid < 255; +} + +static inline struct mctp_hdr *mctp_hdr(struct sk_buff *skb) +{ + return (struct mctp_hdr *)skb_network_header(skb); +} + +/* socket implementation */ +struct mctp_sock { + struct sock sk; + + /* bind() params */ + int bind_net; + mctp_eid_t bind_addr; + __u8 bind_type; + + /* list of mctp_sk_key, for incoming tag lookup. updates protected + * by sk->net->keys_lock + */ + struct hlist_head keys; +}; + +/* Key for matching incoming packets to sockets or reassembly contexts. + * Packets are matched on (src,dest,tag). + * + * Lifetime requirements: + * + * - keys are free()ed via RCU + * + * - a mctp_sk_key contains a reference to a struct sock; this is valid + * for the life of the key. On sock destruction (through unhash), the key is + * removed from lists (see below), and will not be observable after a RCU + * grace period. + * + * any RX occurring within that grace period may still queue to the socket, + * but will hit the SOCK_DEAD case before the socket is freed. + * + * - these mctp_sk_keys appear on two lists: + * 1) the struct mctp_sock->keys list + * 2) the struct netns_mctp->keys list + * + * updates to either list are performed under the netns_mctp->keys + * lock. + * + * - a key may have a sk_buff attached as part of an in-progress message + * reassembly (->reasm_head). The reassembly context is protected by + * reasm_lock, which may be acquired with the keys lock (above) held, if + * necessary. Consequently, keys lock *cannot* be acquired with the + * reasm_lock held. + * + * - there are two destruction paths for a mctp_sk_key: + * + * - through socket unhash (see mctp_sk_unhash). This performs the list + * removal under keys_lock. + * + * - where a key is established to receive a reply message: after receiving + * the (complete) reply, or during reassembly errors. Here, we clean up + * the reassembly context (marking reasm_dead, to prevent another from + * starting), and remove the socket from the netns & socket lists. + */ +struct mctp_sk_key { + mctp_eid_t peer_addr; + mctp_eid_t local_addr; + __u8 tag; /* incoming tag match; invert TO for local */ + + /* we hold a ref to sk when set */ + struct sock *sk; + + /* routing lookup list */ + struct hlist_node hlist; + + /* per-socket list */ + struct hlist_node sklist; + + /* incoming fragment reassembly context */ + spinlock_t reasm_lock; + struct sk_buff *reasm_head; + struct sk_buff **reasm_tailp; + bool reasm_dead; + u8 last_seq; + + struct rcu_head rcu; +}; + +struct mctp_skb_cb { + unsigned int magic; + unsigned int net; + mctp_eid_t src; +}; + +/* skb control-block accessors with a little extra debugging for initial + * development. + * + * TODO: remove checks & mctp_skb_cb->magic; replace callers of __mctp_cb + * with mctp_cb(). + * + * __mctp_cb() is only for the initial ingress code; we should see ->magic set + * at all times after this. + */ +static inline struct mctp_skb_cb *__mctp_cb(struct sk_buff *skb) +{ + struct mctp_skb_cb *cb = (void *)skb->cb; + + cb->magic = 0x4d435450; + return cb; +} + +static inline struct mctp_skb_cb *mctp_cb(struct sk_buff *skb) +{ + struct mctp_skb_cb *cb = (void *)skb->cb; + + WARN_ON(cb->magic != 0x4d435450); + return (void *)(skb->cb); +} + +/* Route definition. + * + * These are held in the pernet->mctp.routes list, with RCU protection for + * removed routes. We hold a reference to the netdev; routes need to be + * dropped on NETDEV_UNREGISTER events. + * + * Updates to the route table are performed under rtnl; all reads under RCU, + * so routes cannot be referenced over a RCU grace period. Specifically: A + * caller cannot block between mctp_route_lookup and passing the route to + * mctp_do_route. + */ +struct mctp_route { + mctp_eid_t min, max; + + struct mctp_dev *dev; + unsigned int mtu; + int (*output)(struct mctp_route *route, + struct sk_buff *skb); + + struct list_head list; + refcount_t refs; + struct rcu_head rcu; +}; + +/* route interfaces */ +struct mctp_route *mctp_route_lookup(struct net *net, unsigned int dnet, + mctp_eid_t daddr); + +int mctp_do_route(struct mctp_route *rt, struct sk_buff *skb); + +int mctp_local_output(struct sock *sk, struct mctp_route *rt, + struct sk_buff *skb, mctp_eid_t daddr, u8 req_tag); + +/* routing <--> device interface */ +unsigned int mctp_default_net(struct net *net); +int mctp_default_net_set(struct net *net, unsigned int index); +int mctp_route_add_local(struct mctp_dev *mdev, mctp_eid_t addr); +int mctp_route_remove_local(struct mctp_dev *mdev, mctp_eid_t addr); +void mctp_route_remove_dev(struct mctp_dev *mdev); + +/* neighbour definitions */ +enum mctp_neigh_source { + MCTP_NEIGH_STATIC, + MCTP_NEIGH_DISCOVER, +}; + +struct mctp_neigh { + struct mctp_dev *dev; + mctp_eid_t eid; + enum mctp_neigh_source source; + + unsigned char ha[MAX_ADDR_LEN]; + + struct list_head list; + struct rcu_head rcu; +}; + +int mctp_neigh_init(void); +void mctp_neigh_exit(void); + +// ret_hwaddr may be NULL, otherwise must have space for MAX_ADDR_LEN +int mctp_neigh_lookup(struct mctp_dev *dev, mctp_eid_t eid, + void *ret_hwaddr); +void mctp_neigh_remove_dev(struct mctp_dev *mdev); + +int mctp_routes_init(void); +void mctp_routes_exit(void); + +void mctp_device_init(void); +void mctp_device_exit(void); + +#endif /* __NET_MCTP_H */ diff --git a/include/net/mctpdevice.h b/include/net/mctpdevice.h new file mode 100644 index 000000000000..57e773ff08bb --- /dev/null +++ b/include/net/mctpdevice.h @@ -0,0 +1,36 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Management Component Transport Protocol (MCTP) - device + * definitions. + * + * Copyright (c) 2021 Code Construct + * Copyright (c) 2021 Google + */ + +#ifndef __NET_MCTPDEVICE_H +#define __NET_MCTPDEVICE_H + +#include <linux/list.h> +#include <linux/types.h> +#include <linux/refcount.h> + +struct mctp_dev { + struct net_device *dev; + + unsigned int net; + + /* Only modified under RTNL. Reads have addrs_lock held */ + u8 *addrs; + size_t num_addrs; + spinlock_t addrs_lock; + + struct rcu_head rcu; +}; + +#define MCTP_INITIAL_DEFAULT_NET 1 + +struct mctp_dev *mctp_dev_get_rtnl(const struct net_device *dev); +struct mctp_dev *__mctp_dev_get(const struct net_device *dev); +struct mctp_dev *mctp_dev_get_rtnl(const struct net_device *dev); + +#endif /* __NET_MCTPDEVICE_H */ diff --git a/include/net/net_namespace.h b/include/net/net_namespace.h index 12cf6d7ea62c..cc54750dd3db 100644 --- a/include/net/net_namespace.h +++ b/include/net/net_namespace.h @@ -34,6 +34,7 @@ #include <net/netns/xdp.h> #include <net/netns/smc.h> #include <net/netns/bpf.h> +#include <net/netns/mctp.h> #include <linux/ns_common.h> #include <linux/idr.h> #include <linux/skbuff.h> @@ -167,6 +168,9 @@ struct net { #ifdef CONFIG_XDP_SOCKETS struct netns_xdp xdp; #endif +#if IS_ENABLED(CONFIG_MCTP) + struct netns_mctp mctp; +#endif #if IS_ENABLED(CONFIG_CRYPTO_USER) struct sock *crypto_nlsk; #endif diff --git a/include/net/netns/mctp.h b/include/net/netns/mctp.h new file mode 100644 index 000000000000..acedef12a35e --- /dev/null +++ b/include/net/netns/mctp.h @@ -0,0 +1,36 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * MCTP per-net structures + */ + +#ifndef __NETNS_MCTP_H__ +#define __NETNS_MCTP_H__ + +#include <linux/types.h> + +struct netns_mctp { + /* Only updated under RTNL, entries freed via RCU */ + struct list_head routes; + + /* Bound sockets: list of sockets bound by type. + * This list is updated from non-atomic contexts (under bind_lock), + * and read (under rcu) in packet rx + */ + struct mutex bind_lock; + struct hlist_head binds; + + /* tag allocations. This list is read and updated from atomic contexts, + * but elements are free()ed after a RCU grace-period + */ + spinlock_t keys_lock; + struct hlist_head keys; + + /* MCTP network */ + unsigned int default_net; + + /* neighbour table */ + struct mutex neigh_lock; + struct list_head neighbours; +}; + +#endif /* __NETNS_MCTP_H__ */ diff --git a/include/uapi/linux/if_arp.h b/include/uapi/linux/if_arp.h index c3cc5a9e5eaf..4783af9fe520 100644 --- a/include/uapi/linux/if_arp.h +++ b/include/uapi/linux/if_arp.h @@ -54,6 +54,7 @@ #define ARPHRD_X25 271 /* CCITT X.25 */ #define ARPHRD_HWX25 272 /* Boards with X.25 in firmware */ #define ARPHRD_CAN 280 /* Controller Area Network */ +#define ARPHRD_MCTP 290 #define ARPHRD_PPP 512 #define ARPHRD_CISCO 513 /* Cisco HDLC */ #define ARPHRD_HDLC ARPHRD_CISCO diff --git a/include/uapi/linux/if_ether.h b/include/uapi/linux/if_ether.h index a0b637911d3c..5f589c7a8382 100644 --- a/include/uapi/linux/if_ether.h +++ b/include/uapi/linux/if_ether.h @@ -151,6 +151,9 @@ #define ETH_P_MAP 0x00F9 /* Qualcomm multiplexing and * aggregation protocol */ +#define ETH_P_MCTP 0x00FA /* Management component transport + * protocol packets + */ /* * This is an Ethernet frame header. diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h index 4882e81514b6..49b22afab78f 100644 --- a/include/uapi/linux/if_link.h +++ b/include/uapi/linux/if_link.h @@ -1260,4 +1260,14 @@ struct ifla_rmnet_flags { __u32 mask; }; +/* MCTP section */ + +enum { + IFLA_MCTP_UNSPEC, + IFLA_MCTP_NET, + __IFLA_MCTP_MAX, +}; + +#define IFLA_MCTP_MAX (__IFLA_MCTP_MAX - 1) + #endif /* _UAPI_LINUX_IF_LINK_H */ diff --git a/include/uapi/linux/mctp.h b/include/uapi/linux/mctp.h new file mode 100644 index 000000000000..52b54d13f385 --- /dev/null +++ b/include/uapi/linux/mctp.h @@ -0,0 +1,36 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ +/* + * Management Component Transport Protocol (MCTP) + * + * Copyright (c) 2021 Code Construct + * Copyright (c) 2021 Google + */ + +#ifndef __UAPI_MCTP_H +#define __UAPI_MCTP_H + +#include <linux/types.h> + +typedef __u8 mctp_eid_t; + +struct mctp_addr { + mctp_eid_t s_addr; +}; + +struct sockaddr_mctp { + unsigned short int smctp_family; + int smctp_network; + struct mctp_addr smctp_addr; + __u8 smctp_type; + __u8 smctp_tag; +}; + +#define MCTP_NET_ANY 0x0 + +#define MCTP_ADDR_NULL 0x00 +#define MCTP_ADDR_ANY 0xff + +#define MCTP_TAG_MASK 0x07 +#define MCTP_TAG_OWNER 0x08 + +#endif /* __UAPI_MCTP_H */ |