diff options
| -rw-r--r-- | include/linux/netfilter/nfnetlink_osf.h | 3 | ||||
| -rw-r--r-- | include/uapi/linux/netfilter/nf_tables.h | 7 | ||||
| -rw-r--r-- | net/netfilter/nfnetlink_osf.c | 46 | ||||
| -rw-r--r-- | net/netfilter/nft_osf.c | 15 |
4 files changed, 44 insertions, 27 deletions
diff --git a/include/linux/netfilter/nfnetlink_osf.h b/include/linux/netfilter/nfnetlink_osf.h index ecf7dab81e9e..c6000046c966 100644 --- a/include/linux/netfilter/nfnetlink_osf.h +++ b/include/linux/netfilter/nfnetlink_osf.h @@ -27,6 +27,7 @@ bool nf_osf_match(const struct sk_buff *skb, u_int8_t family, const struct list_head *nf_osf_fingers); const char *nf_osf_find(const struct sk_buff *skb, - const struct list_head *nf_osf_fingers); + const struct list_head *nf_osf_fingers, + const int ttl_check); #endif /* _NFOSF_H */ diff --git a/include/uapi/linux/netfilter/nf_tables.h b/include/uapi/linux/netfilter/nf_tables.h index 5444e76870bb..579974b0bf0d 100644 --- a/include/uapi/linux/netfilter/nf_tables.h +++ b/include/uapi/linux/netfilter/nf_tables.h @@ -1511,9 +1511,16 @@ enum nft_flowtable_hook_attributes { }; #define NFTA_FLOWTABLE_HOOK_MAX (__NFTA_FLOWTABLE_HOOK_MAX - 1) +/** + * enum nft_osf_attributes - nftables osf expression netlink attributes + * + * @NFTA_OSF_DREG: destination register (NLA_U32: nft_registers) + * @NFTA_OSF_TTL: Value of the TTL osf option (NLA_U8) + */ enum nft_osf_attributes { NFTA_OSF_UNSPEC, NFTA_OSF_DREG, + NFTA_OSF_TTL, __NFTA_OSF_MAX, }; #define NFTA_OSF_MAX (__NFTA_OSF_MAX - 1) diff --git a/net/netfilter/nfnetlink_osf.c b/net/netfilter/nfnetlink_osf.c index 00db27dfd2ff..6f41dd74729d 100644 --- a/net/netfilter/nfnetlink_osf.c +++ b/net/netfilter/nfnetlink_osf.c @@ -30,32 +30,27 @@ EXPORT_SYMBOL_GPL(nf_osf_fingers); static inline int nf_osf_ttl(const struct sk_buff *skb, int ttl_check, unsigned char f_ttl) { + struct in_device *in_dev = __in_dev_get_rcu(skb->dev); const struct iphdr *ip = ip_hdr(skb); - - if (ttl_check != -1) { - if (ttl_check == NF_OSF_TTL_TRUE) - return ip->ttl == f_ttl; - if (ttl_check == NF_OSF_TTL_NOCHECK) - return 1; - else if (ip->ttl <= f_ttl) - return 1; - else { - struct in_device *in_dev = __in_dev_get_rcu(skb->dev); - int ret = 0; - - for_ifa(in_dev) { - if (inet_ifa_match(ip->saddr, ifa)) { - ret = (ip->ttl == f_ttl); - break; - } - } - endfor_ifa(in_dev); - - return ret; + int ret = 0; + + if (ttl_check == NF_OSF_TTL_TRUE) + return ip->ttl == f_ttl; + if (ttl_check == NF_OSF_TTL_NOCHECK) + return 1; + else if (ip->ttl <= f_ttl) + return 1; + + for_ifa(in_dev) { + if (inet_ifa_match(ip->saddr, ifa)) { + ret = (ip->ttl == f_ttl); + break; } } - return ip->ttl == f_ttl; + endfor_ifa(in_dev); + + return ret; } struct nf_osf_hdr_ctx { @@ -213,7 +208,7 @@ nf_osf_match(const struct sk_buff *skb, u_int8_t family, if (!tcp) return false; - ttl_check = (info->flags & NF_OSF_TTL) ? info->ttl : -1; + ttl_check = (info->flags & NF_OSF_TTL) ? info->ttl : 0; list_for_each_entry_rcu(kf, &nf_osf_fingers[ctx.df], finger_entry) { @@ -257,7 +252,8 @@ nf_osf_match(const struct sk_buff *skb, u_int8_t family, EXPORT_SYMBOL_GPL(nf_osf_match); const char *nf_osf_find(const struct sk_buff *skb, - const struct list_head *nf_osf_fingers) + const struct list_head *nf_osf_fingers, + const int ttl_check) { const struct iphdr *ip = ip_hdr(skb); const struct nf_osf_user_finger *f; @@ -275,7 +271,7 @@ const char *nf_osf_find(const struct sk_buff *skb, list_for_each_entry_rcu(kf, &nf_osf_fingers[ctx.df], finger_entry) { f = &kf->finger; - if (!nf_osf_match_one(skb, f, -1, &ctx)) + if (!nf_osf_match_one(skb, f, ttl_check, &ctx)) continue; genre = f->genre; diff --git a/net/netfilter/nft_osf.c b/net/netfilter/nft_osf.c index a35fb59ace73..0b452fd470c4 100644 --- a/net/netfilter/nft_osf.c +++ b/net/netfilter/nft_osf.c @@ -6,10 +6,12 @@ struct nft_osf { enum nft_registers dreg:8; + u8 ttl; }; static const struct nla_policy nft_osf_policy[NFTA_OSF_MAX + 1] = { [NFTA_OSF_DREG] = { .type = NLA_U32 }, + [NFTA_OSF_TTL] = { .type = NLA_U8 }, }; static void nft_osf_eval(const struct nft_expr *expr, struct nft_regs *regs, @@ -33,7 +35,7 @@ static void nft_osf_eval(const struct nft_expr *expr, struct nft_regs *regs, return; } - os_name = nf_osf_find(skb, nf_osf_fingers); + os_name = nf_osf_find(skb, nf_osf_fingers, priv->ttl); if (!os_name) strncpy((char *)dest, "unknown", NFT_OSF_MAXGENRELEN); else @@ -46,6 +48,14 @@ static int nft_osf_init(const struct nft_ctx *ctx, { struct nft_osf *priv = nft_expr_priv(expr); int err; + u8 ttl; + + if (nla_get_u8(tb[NFTA_OSF_TTL])) { + ttl = nla_get_u8(tb[NFTA_OSF_TTL]); + if (ttl > 2) + return -EINVAL; + priv->ttl = ttl; + } priv->dreg = nft_parse_register(tb[NFTA_OSF_DREG]); err = nft_validate_register_store(ctx, priv->dreg, NULL, @@ -60,6 +70,9 @@ static int nft_osf_dump(struct sk_buff *skb, const struct nft_expr *expr) { const struct nft_osf *priv = nft_expr_priv(expr); + if (nla_put_u8(skb, NFTA_OSF_TTL, priv->ttl)) + goto nla_put_failure; + if (nft_dump_register(skb, NFTA_OSF_DREG, priv->dreg)) goto nla_put_failure; |