This new function returns the OS genre as a string. Plan is to use to
from the new nft_osf extension.
Note that this doesn't yet support ttl options, but it could be easily
extended to do so.
Tested-by: Fernando Fernandez Mancera <ffmancera@xxxxxxxxxx>
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
---
include/linux/netfilter/nf_osf.h | 9 +++++++++
net/netfilter/nf_osf.c | 30 ++++++++++++++++++++++++++++++
2 files changed, 39 insertions(+)
diff --git a/include/linux/netfilter/nf_osf.h b/include/linux/netfilter/nf_osf.h
index 0e114c492fb8..aee460fcbd31 100644
--- a/include/linux/netfilter/nf_osf.h
+++ b/include/linux/netfilter/nf_osf.h
@@ -1,3 +1,7 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _NFOSF_H
+#define _NFOSF_H
+
#include <uapi/linux/netfilter/nf_osf.h>
/* Initial window size option state machine: multiple of mss, mtu or
@@ -31,3 +35,8 @@ bool nf_osf_match(const struct sk_buff *skb, u_int8_t family,
int hooknum, struct net_device *in, struct net_device *out,
const struct nf_osf_info *info, struct net *net,
const struct list_head *nf_osf_fingers);
+
+const char *nf_osf_find(const struct sk_buff *skb,
+ const struct list_head *nf_osf_fingers);
+
+#endif /* _NFOSF_H */
diff --git a/net/netfilter/nf_osf.c b/net/netfilter/nf_osf.c
index b44d62d5d9a9..f4c75e982902 100644
--- a/net/netfilter/nf_osf.c
+++ b/net/netfilter/nf_osf.c
@@ -249,4 +249,34 @@ 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 iphdr *ip = ip_hdr(skb);
+ const struct nf_osf_user_finger *f;
+ unsigned char opts[MAX_IPOPTLEN];
+ const struct nf_osf_finger *kf;
+ struct nf_osf_hdr_ctx ctx;
+ const struct tcphdr *tcp;
+ const char *genre = NULL;
+
+ memset(&ctx, 0, sizeof(ctx));
+
+ tcp = nf_osf_hdr_ctx_init(&ctx, skb, ip, opts);
+ if (!tcp)
+ return false;
+
+ 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))
+ continue;
+
+ genre = f->genre;
+ break;
+ }
+
+ return genre;
+}
+EXPORT_SYMBOL_GPL(nf_osf_find);
+
MODULE_LICENSE("GPL");
--
2.11.0
--
To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
