mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-09-12 13:55:32 +00:00
netfilter: nft_osf: Add ttl option support
Add ttl option support to the nftables "osf" expression. Signed-off-by: Fernando Fernandez Mancera <ffmancera@riseup.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit is contained in:
parent
ea9cf2a55a
commit
a218dc82f0
4 changed files with 42 additions and 25 deletions
|
@ -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 */
|
||||
|
|
|
@ -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)
|
||||
|
|
|
@ -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);
|
||||
int ret = 0;
|
||||
|
||||
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;
|
||||
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;
|
||||
}
|
||||
}
|
||||
endfor_ifa(in_dev);
|
||||
|
||||
return ret;
|
||||
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;
|
||||
|
|
|
@ -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;
|
||||
|
||||
|
|
Loading…
Reference in a new issue