From 65ee00a9409f751188a8cdc0988167858eb4a536 Mon Sep 17 00:00:00 2001 From: David Ahern Date: Fri, 24 May 2019 14:43:03 -0700 Subject: [PATCH] net: nexthop uapi New UAPI for nexthops as standalone objects: - defines netlink ancillary header, struct nhmsg - RTM commands for nexthop objects, RTM_*NEXTHOP, - RTNLGRP for nexthop notifications, RTNLGRP_NEXTHOP, - Attributes for creating nexthops, NHA_* - Attribute for route specs to specify a nexthop by id, RTA_NH_ID. The nexthop attributes and semantics follow the route and RTA ones for device, gateway and lwt encap. Unique to nexthop objects are a blackhole and a group which contains references to other nexthop objects. With the exception of blackhole and group, nexthop objects MUST contain a device. Gateway and encap are optional. Nexthop groups can only reference other pre-existing nexthops by id. If the NHA_ID attribute is present that id is used for the nexthop. If not specified, one is auto assigned. Dump requests can include attributes: - NHA_GROUPS to return only nexthop groups, - NHA_MASTER to limit dumps to nexthops with devices enslaved to the given master (e.g., VRF) - NHA_OIF to limit dumps to nexthops using given device nlmsg_route_perms in selinux code is updated for the new RTM comands. Signed-off-by: David Ahern Signed-off-by: David S. Miller --- include/uapi/linux/nexthop.h | 56 ++++++++++++++++++++++++++++++++++++++++++ include/uapi/linux/rtnetlink.h | 10 ++++++++ security/selinux/nlmsgtab.c | 5 +++- 3 files changed, 70 insertions(+), 1 deletion(-) create mode 100644 include/uapi/linux/nexthop.h diff --git a/include/uapi/linux/nexthop.h b/include/uapi/linux/nexthop.h new file mode 100644 index 000000000000..7b61867e9848 --- /dev/null +++ b/include/uapi/linux/nexthop.h @@ -0,0 +1,56 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ +#ifndef _UAPI_LINUX_NEXTHOP_H +#define _UAPI_LINUX_NEXTHOP_H + +#include + +struct nhmsg { + unsigned char nh_family; + unsigned char nh_scope; /* return only */ + unsigned char nh_protocol; /* Routing protocol that installed nh */ + unsigned char resvd; + unsigned int nh_flags; /* RTNH_F flags */ +}; + +/* entry in a nexthop group */ +struct nexthop_grp { + __u32 id; /* nexthop id - must exist */ + __u8 weight; /* weight of this nexthop */ + __u8 resvd1; + __u16 resvd2; +}; + +enum { + NEXTHOP_GRP_TYPE_MPATH, /* default type if not specified */ + __NEXTHOP_GRP_TYPE_MAX, +}; + +#define NEXTHOP_GRP_TYPE_MAX (__NEXTHOP_GRP_TYPE_MAX - 1) + +enum { + NHA_UNSPEC, + NHA_ID, /* u32; id for nexthop. id == 0 means auto-assign */ + + NHA_GROUP, /* array of nexthop_grp */ + NHA_GROUP_TYPE, /* u16 one of NEXTHOP_GRP_TYPE */ + /* if NHA_GROUP attribute is added, no other attributes can be set */ + + NHA_BLACKHOLE, /* flag; nexthop used to blackhole packets */ + /* if NHA_BLACKHOLE is added, OIF, GATEWAY, ENCAP can not be set */ + + NHA_OIF, /* u32; nexthop device */ + NHA_GATEWAY, /* be32 (IPv4) or in6_addr (IPv6) gw address */ + NHA_ENCAP_TYPE, /* u16; lwt encap type */ + NHA_ENCAP, /* lwt encap data */ + + /* NHA_OIF can be appended to dump request to return only + * nexthops using given device + */ + NHA_GROUPS, /* flag; only return nexthop groups in dump */ + NHA_MASTER, /* u32; only return nexthops with given master dev */ + + __NHA_MAX, +}; + +#define NHA_MAX (__NHA_MAX - 1) +#endif diff --git a/include/uapi/linux/rtnetlink.h b/include/uapi/linux/rtnetlink.h index 46399367627f..ce2a623abb75 100644 --- a/include/uapi/linux/rtnetlink.h +++ b/include/uapi/linux/rtnetlink.h @@ -157,6 +157,13 @@ enum { RTM_GETCHAIN, #define RTM_GETCHAIN RTM_GETCHAIN + RTM_NEWNEXTHOP = 104, +#define RTM_NEWNEXTHOP RTM_NEWNEXTHOP + RTM_DELNEXTHOP, +#define RTM_DELNEXTHOP RTM_DELNEXTHOP + RTM_GETNEXTHOP, +#define RTM_GETNEXTHOP RTM_GETNEXTHOP + __RTM_MAX, #define RTM_MAX (((__RTM_MAX + 3) & ~3) - 1) }; @@ -342,6 +349,7 @@ enum rtattr_type_t { RTA_IP_PROTO, RTA_SPORT, RTA_DPORT, + RTA_NH_ID, __RTA_MAX }; @@ -704,6 +712,8 @@ enum rtnetlink_groups { #define RTNLGRP_IPV4_MROUTE_R RTNLGRP_IPV4_MROUTE_R RTNLGRP_IPV6_MROUTE_R, #define RTNLGRP_IPV6_MROUTE_R RTNLGRP_IPV6_MROUTE_R + RTNLGRP_NEXTHOP, +#define RTNLGRP_NEXTHOP RTNLGRP_NEXTHOP __RTNLGRP_MAX }; #define RTNLGRP_MAX (__RTNLGRP_MAX - 1) diff --git a/security/selinux/nlmsgtab.c b/security/selinux/nlmsgtab.c index 9cec81209617..2c75d823d8e2 100644 --- a/security/selinux/nlmsgtab.c +++ b/security/selinux/nlmsgtab.c @@ -83,6 +83,9 @@ static const struct nlmsg_perm nlmsg_route_perms[] = { RTM_NEWCHAIN, NETLINK_ROUTE_SOCKET__NLMSG_WRITE }, { RTM_DELCHAIN, NETLINK_ROUTE_SOCKET__NLMSG_WRITE }, { RTM_GETCHAIN, NETLINK_ROUTE_SOCKET__NLMSG_READ }, + { RTM_NEWNEXTHOP, NETLINK_ROUTE_SOCKET__NLMSG_WRITE }, + { RTM_DELNEXTHOP, NETLINK_ROUTE_SOCKET__NLMSG_WRITE }, + { RTM_GETNEXTHOP, NETLINK_ROUTE_SOCKET__NLMSG_READ }, }; static const struct nlmsg_perm nlmsg_tcpdiag_perms[] = @@ -166,7 +169,7 @@ int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm) * structures at the top of this file with the new mappings * before updating the BUILD_BUG_ON() macro! */ - BUILD_BUG_ON(RTM_MAX != (RTM_NEWCHAIN + 3)); + BUILD_BUG_ON(RTM_MAX != (RTM_NEWNEXTHOP + 3)); err = nlmsg_perm(nlmsg_type, perm, nlmsg_route_perms, sizeof(nlmsg_route_perms)); break; -- 2.11.0