[PATCH nf-next] netfilter: osf: add deprecation notices

[Florian Westphal <fw@strlen.de>]

The p0f fingerprints haven't been updated in years, it doesn't look like
this feature is still in a useful/working state.

Add deprecation notices.  We can remove them again if people still use this
feature.

Signed-off-by: Florian Westphal <fw@strlen.de>
---
 net/netfilter/nfnetlink_osf.c | 3 +++
 net/netfilter/nft_osf.c       | 3 +++
 net/netfilter/xt_osf.c        | 3 +++
 3 files changed, 9 insertions(+)

diff --git a/net/netfilter/nfnetlink_osf.c b/net/netfilter/nfnetlink_osf.c
index d64ce21c7b55..ca943ea71d1a 100644
--- a/net/netfilter/nfnetlink_osf.c
+++ b/net/netfilter/nfnetlink_osf.c
@@ -423,6 +423,9 @@ static int __init nfnl_osf_init(void)
 	int err = -EINVAL;
 	int i;
 
+	pr_warn_once("The osf nfnetlink helper is deprecated and scheduled to be removed in 2027.\n"
+		     "Please contact the netfilter-devel mailing list\n");
+
 	for (i = 0; i < ARRAY_SIZE(nf_osf_fingers); ++i)
 		INIT_LIST_HEAD(&nf_osf_fingers[i]);
 
diff --git a/net/netfilter/nft_osf.c b/net/netfilter/nft_osf.c
index 18003433476c..38d3260a954c 100644
--- a/net/netfilter/nft_osf.c
+++ b/net/netfilter/nft_osf.c
@@ -147,6 +147,9 @@ static struct nft_expr_type nft_osf_type __read_mostly = {
 
 static int __init nft_osf_module_init(void)
 {
+	pr_warn_once("The osf expression is deprecated and scheduled to be removed in 2027.\n"
+		     "Please contact the netfilter-devel mailing list or update your nftables rules\n");
+
 	return nft_register_expr(&nft_osf_type);
 }
 
diff --git a/net/netfilter/xt_osf.c b/net/netfilter/xt_osf.c
index dc9485854002..0d8ee8542e16 100644
--- a/net/netfilter/xt_osf.c
+++ b/net/netfilter/xt_osf.c
@@ -48,6 +48,9 @@ static int __init xt_osf_init(void)
 {
 	int err;
 
+	pr_warn_once("The osf match is deprecated and scheduled to be removed in 2027.\n"
+		     "Please contact the netfilter-devel mailing list or update your iptables rules\n");
+
 	err = xt_register_match(&xt_osf_match);
 	if (err) {
 		pr_err("Failed to register OS fingerprint "
-- 
2.53.0