diff options
| -rw-r--r-- | MAINTAINERS | 1 | ||||
| -rw-r--r-- | include/linux/netdevice.h | 4 | ||||
| -rw-r--r-- | include/net/mctp.h | 14 | ||||
| -rw-r--r-- | include/net/mctpdevice.h | 35 | ||||
| -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 | 1 | ||||
| -rw-r--r-- | net/mctp/Makefile | 2 | ||||
| -rw-r--r-- | net/mctp/af_mctp.c | 8 | ||||
| -rw-r--r-- | net/mctp/device.c | 414 |
10 files changed, 491 insertions, 1 deletions
diff --git a/MAINTAINERS b/MAINTAINERS index e95eb3b00cd2..c2943c227ee6 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -11039,6 +11039,7 @@ L: netdev@vger.kernel.org S: Maintained F: drivers/net/mctp/ F: include/net/mctp.h +F: include/net/mctpdevice.h F: net/mctp/ MAN-PAGES: MANUAL PAGES FOR LINUX -- Sections 2, 3, 4, 5, and 7 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/net/mctp.h b/include/net/mctp.h index 4c01e083be45..61452e03aa85 100644 --- a/include/net/mctp.h +++ b/include/net/mctp.h @@ -10,6 +10,7 @@ #define __NET_MCTP_H #include <linux/bits.h> +#include <linux/mctp.h> /* MCTP packet definitions */ struct mctp_hdr { @@ -32,4 +33,17 @@ struct mctp_hdr { #define MCTP_HDR_TAG_SHIFT 0 #define MCTP_HDR_TAG_MASK GENMASK(2, 0) +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); +} + +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..71a11012fac7 --- /dev/null +++ b/include/net/mctpdevice.h @@ -0,0 +1,35 @@ +/* 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); + +#endif /* __NET_MCTPDEVICE_H */ 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 index 52b54d13f385..a9d8edb3402b 100644 --- a/include/uapi/linux/mctp.h +++ b/include/uapi/linux/mctp.h @@ -26,6 +26,7 @@ struct sockaddr_mctp { }; #define MCTP_NET_ANY 0x0 +#define MCTP_NET_DEFAULT 0x0 #define MCTP_ADDR_NULL 0x00 #define MCTP_ADDR_ANY 0xff diff --git a/net/mctp/Makefile b/net/mctp/Makefile index 7c056b1b7939..2ea98c27b262 100644 --- a/net/mctp/Makefile +++ b/net/mctp/Makefile @@ -1,3 +1,3 @@ # SPDX-License-Identifier: GPL-2.0 obj-$(CONFIG_MCTP) += mctp.o -mctp-objs := af_mctp.o +mctp-objs := af_mctp.o device.o diff --git a/net/mctp/af_mctp.c b/net/mctp/af_mctp.c index b3aeca6486e3..401b4fa141a5 100644 --- a/net/mctp/af_mctp.c +++ b/net/mctp/af_mctp.c @@ -6,13 +6,18 @@ * Copyright (c) 2021 Google */ +#include <linux/if_arp.h> #include <linux/net.h> #include <linux/mctp.h> #include <linux/module.h> #include <linux/socket.h> +#include <net/mctp.h> +#include <net/mctpdevice.h> #include <net/sock.h> +/* socket implementation */ + struct mctp_sock { struct sock sk; }; @@ -152,6 +157,8 @@ static __init int mctp_init(void) if (rc) goto err_unreg_sock; + mctp_device_init(); + return 0; err_unreg_sock: @@ -162,6 +169,7 @@ err_unreg_sock: static __exit void mctp_exit(void) { + mctp_device_exit(); proto_unregister(&mctp_proto); sock_unregister(PF_MCTP); } diff --git a/net/mctp/device.c b/net/mctp/device.c new file mode 100644 index 000000000000..877abe5312cd --- /dev/null +++ b/net/mctp/device.c @@ -0,0 +1,414 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Management Component Transport Protocol (MCTP) - device implementation. + * + * Copyright (c) 2021 Code Construct + * Copyright (c) 2021 Google + */ + +#include <linux/if_link.h> +#include <linux/mctp.h> +#include <linux/netdevice.h> +#include <linux/rcupdate.h> +#include <linux/rtnetlink.h> + +#include <net/addrconf.h> +#include <net/netlink.h> +#include <net/mctp.h> +#include <net/mctpdevice.h> +#include <net/sock.h> + +struct mctp_dump_cb { + int h; + int idx; + size_t a_idx; +}; + +/* unlocked: caller must hold rcu_read_lock */ +struct mctp_dev *__mctp_dev_get(const struct net_device *dev) +{ + return rcu_dereference(dev->mctp_ptr); +} + +struct mctp_dev *mctp_dev_get_rtnl(const struct net_device *dev) +{ + return rtnl_dereference(dev->mctp_ptr); +} + +static void mctp_dev_destroy(struct mctp_dev *mdev) +{ + struct net_device *dev = mdev->dev; + + dev_put(dev); + kfree_rcu(mdev, rcu); +} + +static int mctp_fill_addrinfo(struct sk_buff *skb, struct netlink_callback *cb, + struct mctp_dev *mdev, mctp_eid_t eid) +{ + struct ifaddrmsg *hdr; + struct nlmsghdr *nlh; + + nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, + RTM_NEWADDR, sizeof(*hdr), NLM_F_MULTI); + if (!nlh) + return -EMSGSIZE; + + hdr = nlmsg_data(nlh); + hdr->ifa_family = AF_MCTP; + hdr->ifa_prefixlen = 0; + hdr->ifa_flags = 0; + hdr->ifa_scope = 0; + hdr->ifa_index = mdev->dev->ifindex; + + if (nla_put_u8(skb, IFA_LOCAL, eid)) + goto cancel; + + if (nla_put_u8(skb, IFA_ADDRESS, eid)) + goto cancel; + + nlmsg_end(skb, nlh); + + return 0; + +cancel: + nlmsg_cancel(skb, nlh); + return -EMSGSIZE; +} + +static int mctp_dump_dev_addrinfo(struct mctp_dev *mdev, struct sk_buff *skb, + struct netlink_callback *cb) +{ + struct mctp_dump_cb *mcb = (void *)cb->ctx; + int rc = 0; + + for (; mcb->a_idx < mdev->num_addrs; mcb->a_idx++) { + rc = mctp_fill_addrinfo(skb, cb, mdev, mdev->addrs[mcb->a_idx]); + if (rc < 0) + break; + } + + return rc; +} + +static int mctp_dump_addrinfo(struct sk_buff *skb, struct netlink_callback *cb) +{ + struct mctp_dump_cb *mcb = (void *)cb->ctx; + struct net *net = sock_net(skb->sk); + struct hlist_head *head; + struct net_device *dev; + struct ifaddrmsg *hdr; + struct mctp_dev *mdev; + int ifindex; + int idx, rc; + + hdr = nlmsg_data(cb->nlh); + // filter by ifindex if requested + ifindex = hdr->ifa_index; + + rcu_read_lock(); + for (; mcb->h < NETDEV_HASHENTRIES; mcb->h++, mcb->idx = 0) { + idx = 0; + head = &net->dev_index_head[mcb->h]; + hlist_for_each_entry_rcu(dev, head, index_hlist) { + if (idx >= mcb->idx && + (ifindex == 0 || ifindex == dev->ifindex)) { + mdev = __mctp_dev_get(dev); + if (mdev) { + rc = mctp_dump_dev_addrinfo(mdev, + skb, cb); + // Error indicates full buffer, this + // callback will get retried. + if (rc < 0) + goto out; + } + } + idx++; + // reset for next iteration + mcb->a_idx = 0; + } + } +out: + rcu_read_unlock(); + mcb->idx = idx; + + return skb->len; +} + +static const struct nla_policy ifa_mctp_policy[IFA_MAX + 1] = { + [IFA_ADDRESS] = { .type = NLA_U8 }, + [IFA_LOCAL] = { .type = NLA_U8 }, +}; + +static int mctp_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh, + struct netlink_ext_ack *extack) +{ + struct net *net = sock_net(skb->sk); + struct nlattr *tb[IFA_MAX + 1]; + struct net_device *dev; + struct mctp_addr *addr; + struct mctp_dev *mdev; + struct ifaddrmsg *ifm; + unsigned long flags; + u8 *tmp_addrs; + int rc; + + rc = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_mctp_policy, + extack); + if (rc < 0) + return rc; + + ifm = nlmsg_data(nlh); + + if (tb[IFA_LOCAL]) + addr = nla_data(tb[IFA_LOCAL]); + else if (tb[IFA_ADDRESS]) + addr = nla_data(tb[IFA_ADDRESS]); + else + return -EINVAL; + + /* find device */ + dev = __dev_get_by_index(net, ifm->ifa_index); + if (!dev) + return -ENODEV; + + mdev = mctp_dev_get_rtnl(dev); + if (!mdev) + return -ENODEV; + + if (!mctp_address_ok(addr->s_addr)) + return -EINVAL; + + /* Prevent duplicates. Under RTNL so don't need to lock for reading */ + if (memchr(mdev->addrs, addr->s_addr, mdev->num_addrs)) + return -EEXIST; + + tmp_addrs = kmalloc(mdev->num_addrs + 1, GFP_KERNEL); + if (!tmp_addrs) + return -ENOMEM; + memcpy(tmp_addrs, mdev->addrs, mdev->num_addrs); + tmp_addrs[mdev->num_addrs] = addr->s_addr; + + /* Lock to write */ + spin_lock_irqsave(&mdev->addrs_lock, flags); + mdev->num_addrs++; + swap(mdev->addrs, tmp_addrs); + spin_unlock_irqrestore(&mdev->addrs_lock, flags); + + kfree(tmp_addrs); + + return 0; +} + +static int mctp_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh, + struct netlink_ext_ack *extack) +{ + struct net *net = sock_net(skb->sk); + struct nlattr *tb[IFA_MAX + 1]; + struct net_device *dev; + struct mctp_addr *addr; + struct mctp_dev *mdev; + struct ifaddrmsg *ifm; + unsigned long flags; + u8 *pos; + int rc; + + rc = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_mctp_policy, + extack); + if (rc < 0) + return rc; + + ifm = nlmsg_data(nlh); + + if (tb[IFA_LOCAL]) + addr = nla_data(tb[IFA_LOCAL]); + else if (tb[IFA_ADDRESS]) + addr = nla_data(tb[IFA_ADDRESS]); + else + return -EINVAL; + + /* find device */ + dev = __dev_get_by_index(net, ifm->ifa_index); + if (!dev) + return -ENODEV; + + mdev = mctp_dev_get_rtnl(dev); + if (!mdev) + return -ENODEV; + + pos = memchr(mdev->addrs, addr->s_addr, mdev->num_addrs); + if (!pos) + return -ENOENT; + + spin_lock_irqsave(&mdev->addrs_lock, flags); + memmove(pos, pos + 1, mdev->num_addrs - 1 - (pos - mdev->addrs)); + mdev->num_addrs--; + spin_unlock_irqrestore(&mdev->addrs_lock, flags); + + return 0; +} + +static struct mctp_dev *mctp_add_dev(struct net_device *dev) +{ + struct mctp_dev *mdev; + + ASSERT_RTNL(); + + mdev = kzalloc(sizeof(*mdev), GFP_KERNEL); + if (!mdev) + return ERR_PTR(-ENOMEM); + + spin_lock_init(&mdev->addrs_lock); + + mdev->net = MCTP_INITIAL_DEFAULT_NET; + + /* associate to net_device */ + rcu_assign_pointer(dev->mctp_ptr, mdev); + dev_hold(dev); + mdev->dev = dev; + + return mdev; +} + +static int mctp_fill_link_af(struct sk_buff *skb, + const struct net_device *dev, u32 ext_filter_mask) +{ + struct mctp_dev *mdev; + + mdev = mctp_dev_get_rtnl(dev); + if (!mdev) + return -ENODATA; + if (nla_put_u32(skb, IFLA_MCTP_NET, mdev->net)) + return -EMSGSIZE; + return 0; +} + +static size_t mctp_get_link_af_size(const struct net_device *dev, + u32 ext_filter_mask) +{ + struct mctp_dev *mdev; + unsigned int ret; + + /* caller holds RCU */ + mdev = __mctp_dev_get(dev); + if (!mdev) + return 0; + ret = nla_total_size(4); /* IFLA_MCTP_NET */ + return ret; +} + +static const struct nla_policy ifla_af_mctp_policy[IFLA_MCTP_MAX + 1] = { + [IFLA_MCTP_NET] = { .type = NLA_U32 }, +}; + +static int mctp_set_link_af(struct net_device *dev, const struct nlattr *attr, + struct netlink_ext_ack *extack) +{ + struct nlattr *tb[IFLA_MCTP_MAX + 1]; + struct mctp_dev *mdev; + int rc; + + rc = nla_parse_nested(tb, IFLA_MCTP_MAX, attr, ifla_af_mctp_policy, + NULL); + if (rc) + return rc; + + mdev = mctp_dev_get_rtnl(dev); + if (!mdev) + return 0; + + if (tb[IFLA_MCTP_NET]) + WRITE_ONCE(mdev->net, nla_get_u32(tb[IFLA_MCTP_NET])); + + return 0; +} + +static void mctp_unregister(struct net_device *dev) +{ + struct mctp_dev *mdev; + + mdev = mctp_dev_get_rtnl(dev); + + if (!mdev) + return; + + RCU_INIT_POINTER(mdev->dev->mctp_ptr, NULL); + + kfree(mdev->addrs); + + mctp_dev_destroy(mdev); +} + +static int mctp_register(struct net_device *dev) +{ + struct mctp_dev *mdev; + + /* Already registered? */ + if (rtnl_dereference(dev->mctp_ptr)) + return 0; + + /* only register specific types; MCTP-specific and loopback for now */ + if (dev->type != ARPHRD_MCTP && dev->type != ARPHRD_LOOPBACK) + return 0; + + mdev = mctp_add_dev(dev); + if (IS_ERR(mdev)) + return PTR_ERR(mdev); + + return 0; +} + +static int mctp_dev_notify(struct notifier_block *this, unsigned long event, + void *ptr) +{ + struct net_device *dev = netdev_notifier_info_to_dev(ptr); + int rc; + + switch (event) { + case NETDEV_REGISTER: + rc = mctp_register(dev); + if (rc) + return notifier_from_errno(rc); + break; + case NETDEV_UNREGISTER: + mctp_unregister(dev); + break; + } + + return NOTIFY_OK; +} + +static struct rtnl_af_ops mctp_af_ops = { + .family = AF_MCTP, + .fill_link_af = mctp_fill_link_af, + .get_link_af_size = mctp_get_link_af_size, + .set_link_af = mctp_set_link_af, +}; + +static struct notifier_block mctp_dev_nb = { + .notifier_call = mctp_dev_notify, + .priority = ADDRCONF_NOTIFY_PRIORITY, +}; + +void __init mctp_device_init(void) +{ + register_netdevice_notifier(&mctp_dev_nb); + + rtnl_register_module(THIS_MODULE, PF_MCTP, RTM_GETADDR, + NULL, mctp_dump_addrinfo, 0); + rtnl_register_module(THIS_MODULE, PF_MCTP, RTM_NEWADDR, + mctp_rtm_newaddr, NULL, 0); + rtnl_register_module(THIS_MODULE, PF_MCTP, RTM_DELADDR, + mctp_rtm_deladdr, NULL, 0); + rtnl_af_register(&mctp_af_ops); +} + +void __exit mctp_device_exit(void) +{ + rtnl_af_unregister(&mctp_af_ops); + rtnl_unregister(PF_MCTP, RTM_DELADDR); + rtnl_unregister(PF_MCTP, RTM_NEWADDR); + rtnl_unregister(PF_MCTP, RTM_GETADDR); + + unregister_netdevice_notifier(&mctp_dev_nb); +} |