From: Lorenzo Colitti Date: Thu, 3 Nov 2016 17:23:42 +0000 (+0900) Subject: net: core: add UID to flows, rules, and routes X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=092f27a6bfb1e847a5a6d6f2703ee976e745aac9;p=GitHub%2FLineageOS%2Fandroid_kernel_samsung_universal7580.git net: core: add UID to flows, rules, and routes - Define a new FIB rule attributes, FRA_UID_RANGE, to describe a range of UIDs. - Define a RTA_UID attribute for per-UID route lookups and dumps. - Support passing these attributes to and from userspace via rtnetlink. The value INVALID_UID indicates no UID was specified. - Add a UID field to the flow structures. [Backport of net-next 622ec2c9d52405973c9f1ca5116eb1c393adfc7d] Bug: 16355602 Change-Id: I7e3ab388ed862c4b7e39dc8b0209d977cb1129ac Signed-off-by: Lorenzo Colitti Signed-off-by: David S. Miller --- diff --git a/include/net/fib_rules.h b/include/net/fib_rules.h index e361f488242..21666fbdb72 100644 --- a/include/net/fib_rules.h +++ b/include/net/fib_rules.h @@ -8,6 +8,11 @@ #include #include +struct fib_kuid_range { + kuid_t start; + kuid_t end; +}; + struct fib_rule { struct list_head list; atomic_t refcnt; @@ -23,6 +28,7 @@ struct fib_rule { struct fib_rule __rcu *ctarget; char iifname[IFNAMSIZ]; char oifname[IFNAMSIZ]; + struct fib_kuid_range uid_range; struct rcu_head rcu; struct net * fr_net; }; @@ -80,7 +86,8 @@ struct fib_rules_ops { [FRA_FWMARK] = { .type = NLA_U32 }, \ [FRA_FWMASK] = { .type = NLA_U32 }, \ [FRA_TABLE] = { .type = NLA_U32 }, \ - [FRA_GOTO] = { .type = NLA_U32 } + [FRA_GOTO] = { .type = NLA_U32 }, \ + [FRA_UID_RANGE] = { .len = sizeof(struct fib_rule_uid_range) } static inline void fib_rule_get(struct fib_rule *rule) { diff --git a/include/net/flow.h b/include/net/flow.h index 0eb5516a4ca..1964eeb57a3 100644 --- a/include/net/flow.h +++ b/include/net/flow.h @@ -10,6 +10,7 @@ #include #include #include +#include /* * ifindex generation is per-net namespace, and loopback is @@ -31,6 +32,7 @@ struct flowi_common { #define FLOWI_FLAG_CAN_SLEEP 0x02 #define FLOWI_FLAG_KNOWN_NH 0x04 __u32 flowic_secid; + kuid_t flowic_uid; }; union flowi_uli { @@ -67,6 +69,7 @@ struct flowi4 { #define flowi4_proto __fl_common.flowic_proto #define flowi4_flags __fl_common.flowic_flags #define flowi4_secid __fl_common.flowic_secid +#define flowi4_uid __fl_common.flowic_uid /* (saddr,daddr) must be grouped, same order as in IP header */ __be32 saddr; @@ -123,6 +126,7 @@ struct flowi6 { #define flowi6_proto __fl_common.flowic_proto #define flowi6_flags __fl_common.flowic_flags #define flowi6_secid __fl_common.flowic_secid +#define flowi6_uid __fl_common.flowic_uid struct in6_addr daddr; struct in6_addr saddr; __be32 flowlabel; @@ -166,6 +170,7 @@ struct flowi { #define flowi_proto u.__fl_common.flowic_proto #define flowi_flags u.__fl_common.flowic_flags #define flowi_secid u.__fl_common.flowic_secid +#define flowi_uid u.__fl_common.flowic_uid } __attribute__((__aligned__(BITS_PER_LONG/8))); static inline struct flowi *flowi4_to_flowi(struct flowi4 *fl4) diff --git a/include/uapi/linux/fib_rules.h b/include/uapi/linux/fib_rules.h index 51da65b68b8..209abc4faf7 100644 --- a/include/uapi/linux/fib_rules.h +++ b/include/uapi/linux/fib_rules.h @@ -29,6 +29,11 @@ struct fib_rule_hdr { __u32 flags; }; +struct fib_rule_uid_range { + __u32 start; + __u32 end; +}; + enum { FRA_UNSPEC, FRA_DST, /* destination address */ @@ -49,6 +54,9 @@ enum { FRA_TABLE, /* Extended table id */ FRA_FWMASK, /* mask for netfilter mark */ FRA_OIFNAME, + FRA_PAD, + FRA_L3MDEV, /* iif or oif is l3mdev goto its table */ + FRA_UID_RANGE, /* UID range */ __FRA_MAX }; diff --git a/include/uapi/linux/rtnetlink.h b/include/uapi/linux/rtnetlink.h index 7a2144e1afa..f4a2f522bf9 100644 --- a/include/uapi/linux/rtnetlink.h +++ b/include/uapi/linux/rtnetlink.h @@ -297,6 +297,15 @@ enum rtattr_type_t { RTA_TABLE, RTA_MARK, RTA_MFC_STATS, + RTA_UNUSED1, /* RTA_MFC_STATS in later kernels */ + RTA_VIA, + RTA_NEWDST, + RTA_PREF, + RTA_ENCAP_TYPE, + RTA_ENCAP, + RTA_EXPIRES, + RTA_PAD, + RTA_UID, __RTA_MAX }; diff --git a/net/core/fib_rules.c b/net/core/fib_rules.c index 84340a2605e..e7e914e62f5 100644 --- a/net/core/fib_rules.c +++ b/net/core/fib_rules.c @@ -17,6 +17,11 @@ #include #include +static const struct fib_kuid_range fib_kuid_range_unset = { + KUIDT_INIT(0), + KUIDT_INIT(~0), +}; + int fib_default_rule_add(struct fib_rules_ops *ops, u32 pref, u32 table, u32 flags) { @@ -32,6 +37,7 @@ int fib_default_rule_add(struct fib_rules_ops *ops, r->table = table; r->flags = flags; r->fr_net = hold_net(ops->fro_net); + r->uid_range = fib_kuid_range_unset; /* The lock is not required here, the list in unreacheable * at the moment this function is called */ @@ -179,6 +185,28 @@ void fib_rules_unregister(struct fib_rules_ops *ops) } EXPORT_SYMBOL_GPL(fib_rules_unregister); +static int uid_range_set(struct fib_kuid_range *range) +{ + return uid_valid(range->start) && uid_valid(range->end); +} + static struct fib_kuid_range nla_get_kuid_range(struct nlattr **tb) +{ + struct fib_rule_uid_range *in; + struct fib_kuid_range out; + in = (struct fib_rule_uid_range *)nla_data(tb[FRA_UID_RANGE]); + out.start = make_kuid(current_user_ns(), in->start); + out.end = make_kuid(current_user_ns(), in->end); + return out; +} + static int nla_put_uid_range(struct sk_buff *skb, struct fib_kuid_range *range) +{ + struct fib_rule_uid_range out = { + from_kuid_munged(current_user_ns(), range->start), + from_kuid_munged(current_user_ns(), range->end) + }; + return nla_put(skb, FRA_UID_RANGE, sizeof(out), &out); +} + static int fib_rule_match(struct fib_rule *rule, struct fib_rules_ops *ops, struct flowi *fl, int flags) { @@ -193,6 +221,10 @@ static int fib_rule_match(struct fib_rule *rule, struct fib_rules_ops *ops, if ((rule->mark ^ fl->flowi_mark) & rule->mark_mask) goto out; + if (uid_lt(fl->flowi_uid, rule->uid_range.start) || + uid_gt(fl->flowi_uid, rule->uid_range.end)) + goto out; + ret = ops->match(rule, fl, flags); out: return (rule->flags & FIB_RULE_INVERT) ? !ret : ret; @@ -363,6 +395,19 @@ static int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr* nlh) } else if (rule->action == FR_ACT_GOTO) goto errout_free; + if (tb[FRA_UID_RANGE]) { + if (current_user_ns() != net->user_ns) { + err = -EPERM; + goto errout_free; + } + rule->uid_range = nla_get_kuid_range(tb); + if (!uid_range_set(&rule->uid_range) || + !uid_lte(rule->uid_range.start, rule->uid_range.end)) + goto errout_free; + } else { + rule->uid_range = fib_kuid_range_unset; + } + err = ops->configure(rule, skb, frh, tb); if (err < 0) goto errout_free; @@ -422,6 +467,7 @@ static int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr* nlh) struct fib_rules_ops *ops = NULL; struct fib_rule *rule, *tmp; struct nlattr *tb[FRA_MAX+1]; + struct fib_kuid_range range; int err = -EINVAL; if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh))) @@ -441,6 +487,14 @@ static int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr* nlh) if (err < 0) goto errout; + if (tb[FRA_UID_RANGE]) { + range = nla_get_kuid_range(tb); + if (!uid_range_set(&range)) + goto errout; + } else { + range = fib_kuid_range_unset; + } + list_for_each_entry(rule, &ops->rules_list, list) { if (frh->action && (frh->action != rule->action)) continue; @@ -469,6 +523,11 @@ static int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr* nlh) (rule->mark_mask != nla_get_u32(tb[FRA_FWMASK]))) continue; + if (uid_range_set(&range) && + (!uid_eq(rule->uid_range.start, range.start) || + !uid_eq(rule->uid_range.end, range.end))) + continue; + if (!ops->compare(rule, frh, tb)) continue; @@ -525,7 +584,8 @@ static inline size_t fib_rule_nlmsg_size(struct fib_rules_ops *ops, + nla_total_size(4) /* FRA_PRIORITY */ + nla_total_size(4) /* FRA_TABLE */ + nla_total_size(4) /* FRA_FWMARK */ - + nla_total_size(4); /* FRA_FWMASK */ + + nla_total_size(4) /* FRA_FWMASK */ + + nla_total_size(sizeof(struct fib_kuid_range)); if (ops->nlmsg_payload) payload += ops->nlmsg_payload(rule); @@ -579,7 +639,9 @@ static int fib_nl_fill_rule(struct sk_buff *skb, struct fib_rule *rule, ((rule->mark_mask || rule->mark) && nla_put_u32(skb, FRA_FWMASK, rule->mark_mask)) || (rule->target && - nla_put_u32(skb, FRA_GOTO, rule->target))) + nla_put_u32(skb, FRA_GOTO, rule->target)) || + (uid_range_set(&rule->uid_range) && + nla_put_uid_range(skb, &rule->uid_range))) goto nla_put_failure; if (ops->fill(rule, skb, frh) < 0) goto nla_put_failure; diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c index 0f299ce1b4b..42da0b216bb 100644 --- a/net/ipv4/fib_frontend.c +++ b/net/ipv4/fib_frontend.c @@ -531,6 +531,7 @@ const struct nla_policy rtm_ipv4_policy[RTA_MAX + 1] = { [RTA_METRICS] = { .type = NLA_NESTED }, [RTA_MULTIPATH] = { .len = sizeof(struct rtnexthop) }, [RTA_FLOW] = { .type = NLA_U32 }, + [RTA_UID] = { .type = NLA_U32 }, }; static int rtm_to_fib_config(struct net *net, struct sk_buff *skb, diff --git a/net/ipv4/route.c b/net/ipv4/route.c index fe162ac7ecc..c564dcf2c80 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -2327,6 +2327,11 @@ static int rt_fill_info(struct net *net, __be32 dst, __be32 src, nla_put_u32(skb, RTA_MARK, fl4->flowi4_mark)) goto nla_put_failure; + if (!uid_eq(fl4->flowi4_uid, INVALID_UID) && + nla_put_u32(skb, RTA_UID, + from_kuid_munged(current_user_ns(), fl4->flowi4_uid))) + goto nla_put_failure; + error = rt->dst.error; if (rt_is_input_route(rt)) { @@ -2377,6 +2382,7 @@ static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh) int err; int mark; struct sk_buff *skb; + kuid_t uid; err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv4_policy); if (err < 0) @@ -2404,6 +2410,10 @@ static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh) dst = tb[RTA_DST] ? nla_get_be32(tb[RTA_DST]) : 0; iif = tb[RTA_IIF] ? nla_get_u32(tb[RTA_IIF]) : 0; mark = tb[RTA_MARK] ? nla_get_u32(tb[RTA_MARK]) : 0; + if (tb[RTA_UID]) + uid = make_kuid(current_user_ns(), nla_get_u32(tb[RTA_UID])); + else + uid = (iif ? INVALID_UID : current_uid()); memset(&fl4, 0, sizeof(fl4)); fl4.daddr = dst; @@ -2411,6 +2421,7 @@ static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh) fl4.flowi4_tos = rtm->rtm_tos; fl4.flowi4_oif = tb[RTA_OIF] ? nla_get_u32(tb[RTA_OIF]) : 0; fl4.flowi4_mark = mark; + fl4.flowi4_uid = uid; if (iif) { struct net_device *dev; diff --git a/net/ipv6/route.c b/net/ipv6/route.c index 7c46620fe71..4e1e02a765f 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -2244,6 +2244,7 @@ static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = { [RTA_PRIORITY] = { .type = NLA_U32 }, [RTA_METRICS] = { .type = NLA_NESTED }, [RTA_MULTIPATH] = { .len = sizeof(struct rtnexthop) }, + [RTA_UID] = { .type = NLA_U32 }, }; static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh, @@ -2632,6 +2633,12 @@ static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh) if (tb[RTA_OIF]) oif = nla_get_u32(tb[RTA_OIF]); + if (tb[RTA_UID]) + fl6.flowi6_uid = make_kuid(current_user_ns(), + nla_get_u32(tb[RTA_UID])); + else + fl6.flowi6_uid = iif ? INVALID_UID : current_uid(); + if (iif) { struct net_device *dev; int flags = 0;