diff --git a/include/net/netns/xfrm.h b/include/net/netns/xfrm.h index e946366e8ba5f2..88c647302977a2 100644 --- a/include/net/netns/xfrm.h +++ b/include/net/netns/xfrm.h @@ -65,6 +65,13 @@ struct netns_xfrm { u32 sysctl_aevent_rseqth; int sysctl_larval_drop; u32 sysctl_acq_expires; + + u8 policy_default; +#define XFRM_POL_DEFAULT_IN 1 +#define XFRM_POL_DEFAULT_OUT 2 +#define XFRM_POL_DEFAULT_FWD 4 +#define XFRM_POL_DEFAULT_MASK 7 + #ifdef CONFIG_SYSCTL struct ctl_table_header *sysctl_hdr; #endif diff --git a/include/net/xfrm.h b/include/net/xfrm.h index cbff7c2a97246a..2308210793a016 100644 --- a/include/net/xfrm.h +++ b/include/net/xfrm.h @@ -1075,6 +1075,22 @@ xfrm_state_addr_cmp(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x, un } #ifdef CONFIG_XFRM +static inline bool +xfrm_default_allow(struct net *net, int dir) +{ + u8 def = net->xfrm.policy_default; + + switch (dir) { + case XFRM_POLICY_IN: + return def & XFRM_POL_DEFAULT_IN ? false : true; + case XFRM_POLICY_OUT: + return def & XFRM_POL_DEFAULT_OUT ? false : true; + case XFRM_POLICY_FWD: + return def & XFRM_POL_DEFAULT_FWD ? false : true; + } + return false; +} + int __xfrm_policy_check(struct sock *, int dir, struct sk_buff *skb, unsigned short family); @@ -1088,9 +1104,13 @@ static inline int __xfrm_policy_check2(struct sock *sk, int dir, if (sk && sk->sk_policy[XFRM_POLICY_IN]) return __xfrm_policy_check(sk, ndir, skb, family); - return (!net->xfrm.policy_count[dir] && !secpath_exists(skb)) || - (skb_dst(skb) && (skb_dst(skb)->flags & DST_NOPOLICY)) || - __xfrm_policy_check(sk, ndir, skb, family); + if (xfrm_default_allow(net, dir)) + return (!net->xfrm.policy_count[dir] && !secpath_exists(skb)) || + (skb_dst(skb) && (skb_dst(skb)->flags & DST_NOPOLICY)) || + __xfrm_policy_check(sk, ndir, skb, family); + else + return (skb_dst(skb) && (skb_dst(skb)->flags & DST_NOPOLICY)) || + __xfrm_policy_check(sk, ndir, skb, family); } static inline int xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, unsigned short family) @@ -1142,9 +1162,13 @@ static inline int xfrm_route_forward(struct sk_buff *skb, unsigned short family) { struct net *net = dev_net(skb->dev); - return !net->xfrm.policy_count[XFRM_POLICY_OUT] || - (skb_dst(skb)->flags & DST_NOXFRM) || - __xfrm_route_forward(skb, family); + if (xfrm_default_allow(net, XFRM_POLICY_FWD)) + return !net->xfrm.policy_count[XFRM_POLICY_OUT] || + (skb_dst(skb)->flags & DST_NOXFRM) || + __xfrm_route_forward(skb, family); + else + return (skb_dst(skb)->flags & DST_NOXFRM) || + __xfrm_route_forward(skb, family); } static inline int xfrm4_route_forward(struct sk_buff *skb) diff --git a/include/uapi/linux/xfrm.h b/include/uapi/linux/xfrm.h index ffc6a5391bb7bb..6e809510619251 100644 --- a/include/uapi/linux/xfrm.h +++ b/include/uapi/linux/xfrm.h @@ -213,6 +213,11 @@ enum { XFRM_MSG_GETSPDINFO, #define XFRM_MSG_GETSPDINFO XFRM_MSG_GETSPDINFO + XFRM_MSG_SETDEFAULT, +#define XFRM_MSG_SETDEFAULT XFRM_MSG_SETDEFAULT + XFRM_MSG_GETDEFAULT, +#define XFRM_MSG_GETDEFAULT XFRM_MSG_GETDEFAULT + XFRM_MSG_MAPPING, #define XFRM_MSG_MAPPING XFRM_MSG_MAPPING __XFRM_MSG_MAX @@ -508,6 +513,11 @@ struct xfrm_user_offload { #define XFRM_OFFLOAD_IPV6 1 #define XFRM_OFFLOAD_INBOUND 2 +struct xfrm_userpolicy_default { + __u8 dirmask; + __u8 action; +}; + #ifndef __KERNEL__ /* backwards compatibility for userspace */ #define XFRMGRP_ACQUIRE 1 diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c index 827d842550217f..d5cb082e11fc31 100644 --- a/net/xfrm/xfrm_policy.c +++ b/net/xfrm/xfrm_policy.c @@ -3165,6 +3165,11 @@ struct dst_entry *xfrm_lookup_with_ifid(struct net *net, return dst; nopol: + if (!(dst_orig->dev->flags & IFF_LOOPBACK) && + !xfrm_default_allow(net, dir)) { + err = -EPERM; + goto error; + } if (!(flags & XFRM_LOOKUP_ICMP)) { dst = dst_orig; goto ok; @@ -3553,6 +3558,11 @@ int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, } if (!pol) { + if (!xfrm_default_allow(net, dir)) { + XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS); + return 0; + } + if (sp && secpath_has_nontransport(sp, 0, &xerr_idx)) { xfrm_secpath_reject(xerr_idx, skb, &fl); XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS); @@ -3607,6 +3617,12 @@ int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, tpp[ti++] = &pols[pi]->xfrm_vec[i]; } xfrm_nr = ti; + + if (!xfrm_default_allow(net, dir) && !xfrm_nr) { + XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOSTATES); + goto reject; + } + if (npols > 1) { xfrm_tmpl_sort(stp, tpp, xfrm_nr, family); tpp = stp; diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c index b47d613409b70a..4eafd1130c3e2f 100644 --- a/net/xfrm/xfrm_user.c +++ b/net/xfrm/xfrm_user.c @@ -1961,6 +1961,54 @@ static struct sk_buff *xfrm_policy_netlink(struct sk_buff *in_skb, return skb; } +static int xfrm_set_default(struct sk_buff *skb, struct nlmsghdr *nlh, + struct nlattr **attrs) +{ + struct net *net = sock_net(skb->sk); + struct xfrm_userpolicy_default *up = nlmsg_data(nlh); + u8 dirmask = (1 << up->dirmask) & XFRM_POL_DEFAULT_MASK; + u8 old_default = net->xfrm.policy_default; + + net->xfrm.policy_default = (old_default & (0xff ^ dirmask)) + | (up->action << up->dirmask); + + rt_genid_bump_all(net); + + return 0; +} + +static int xfrm_get_default(struct sk_buff *skb, struct nlmsghdr *nlh, + struct nlattr **attrs) +{ + struct sk_buff *r_skb; + struct nlmsghdr *r_nlh; + struct net *net = sock_net(skb->sk); + struct xfrm_userpolicy_default *r_up, *up; + int len = NLMSG_ALIGN(sizeof(struct xfrm_userpolicy_default)); + u32 portid = NETLINK_CB(skb).portid; + u32 seq = nlh->nlmsg_seq; + + up = nlmsg_data(nlh); + + r_skb = nlmsg_new(len, GFP_ATOMIC); + if (!r_skb) + return -ENOMEM; + + r_nlh = nlmsg_put(r_skb, portid, seq, XFRM_MSG_GETDEFAULT, sizeof(*r_up), 0); + if (!r_nlh) { + kfree_skb(r_skb); + return -EMSGSIZE; + } + + r_up = nlmsg_data(r_nlh); + + r_up->action = ((net->xfrm.policy_default & (1 << up->dirmask)) >> up->dirmask); + r_up->dirmask = up->dirmask; + nlmsg_end(r_skb, r_nlh); + + return nlmsg_unicast(net->xfrm.nlsk, r_skb, portid); +} + static int xfrm_get_policy(struct sk_buff *skb, struct nlmsghdr *nlh, struct nlattr **attrs) { @@ -2664,6 +2712,8 @@ const int xfrm_msg_min[XFRM_NR_MSGTYPES] = { [XFRM_MSG_GETSADINFO - XFRM_MSG_BASE] = sizeof(u32), [XFRM_MSG_NEWSPDINFO - XFRM_MSG_BASE] = sizeof(u32), [XFRM_MSG_GETSPDINFO - XFRM_MSG_BASE] = sizeof(u32), + [XFRM_MSG_SETDEFAULT - XFRM_MSG_BASE] = XMSGSIZE(xfrm_userpolicy_default), + [XFRM_MSG_GETDEFAULT - XFRM_MSG_BASE] = XMSGSIZE(xfrm_userpolicy_default), }; EXPORT_SYMBOL_GPL(xfrm_msg_min); @@ -2743,6 +2793,8 @@ static const struct xfrm_link { .nla_pol = xfrma_spd_policy, .nla_max = XFRMA_SPD_MAX }, [XFRM_MSG_GETSPDINFO - XFRM_MSG_BASE] = { .doit = xfrm_get_spdinfo }, + [XFRM_MSG_SETDEFAULT - XFRM_MSG_BASE] = { .doit = xfrm_set_default }, + [XFRM_MSG_GETDEFAULT - XFRM_MSG_BASE] = { .doit = xfrm_get_default }, }; static int xfrm_user_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh,