extensions: libxt_NFLOG: Add translation to nft

PATCH In review Shivani Bhardwaj 3 participants 5 messages Dec 21, 2015 – Dec 22, 2015 netfilter

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Shivani Bhardwaj

author

2015-12-21 17:36 UTC #0 lore raw

PATCH 1/1 extensions: libxt_NFLOG: Add translation to nft

Add translation for NF Logging to nftables.

Examples:

$ sudo iptables-translate -A OUTPUT -j NFLOG --nflog-group 30
nft add rule ip filter OUTPUT counter log group 30

$ sudo iptables-translate -A FORWARD -j NFLOG --nflog-group 32 --nflog-prefix "Prefix 1.0"
nft add rule ip filter FORWARD counter log prefix \"Prefix 1.0\" log group 32

$ sudo iptables-translate -I INPUT -j NFLOG --nflog-range 256
nft insert rule ip filter INPUT counter log snaplen 256

$ sudo iptables-translate -I INPUT -j NFLOG --nflog-threshold 25
nft insert rule ip filter INPUT counter log queue-threshold 25

Signed-off-by Shivani Bhardwaj <[email protected]>

---
 extensions/libxt_NFLOG.c | 28 +++++++++++++++++++++++++++-
 1 file changed, 27 insertions(+), 1 deletion(-)

extensions/libxt_NFLOG.c +27 -1

index 448576a..3d05ce0 100644
@@ -72,7 +72,7 @@ static void nflog_print(const struct xt_nflog_info *info, char *prefix)
 }
 
 static void NFLOG_print(const void *ip, const struct xt_entry_target *target,
-                        int numeric)
+			int numeric)
 {
 	const struct xt_nflog_info *info = (struct xt_nflog_info *)target->data;

@@ -86,6 +86,31 @@ static void NFLOG_save(const void *ip, const struct xt_entry_target *target)
 	nflog_print(info, "--");
 }
 
+static void nflog_print_xlate(const struct xt_nflog_info *info,
+			      char *prefix, struct xt_buf *buf)
+{
+	if (info->prefix[0] != '\0')
+		xt_buf_add(buf, "%slog prefix \\\"%s\\\" ",
+			   prefix, info->prefix);
+	if (info->group)
+		xt_buf_add(buf, "%slog group %u ", prefix, info->group);
+	if (info->len)
+		xt_buf_add(buf, "%slog snaplen %u ", prefix, info->len);
+	if (info->threshold != XT_NFLOG_DEFAULT_THRESHOLD)
+		xt_buf_add(buf, "%slog queue-threshold %u ",
+			   prefix, info->threshold);
+}
+
+static int NFLOG_xlate(const struct xt_entry_target *target,
+		       struct xt_buf *buf, int numeric)
+{
+	const struct xt_nflog_info *info = (struct xt_nflog_info *)target->data;
+
+	nflog_print_xlate(info, "", buf);
+
+	return 1;
+}
+
 static struct xtables_target nflog_target = {
 	.family		= NFPROTO_UNSPEC,
 	.name		= "NFLOG",

@@ -98,6 +123,7 @@ static struct xtables_target nflog_target = {
 	.print		= NFLOG_print,
 	.save		= NFLOG_save,
 	.x6_options	= NFLOG_opts,
+	.xlate		= NFLOG_xlate,
 };
 
 void _init(void)

Signature · 1 line

1.9.1

Arturo Borrero Gonzalez

2015-12-22 12:40 UTC #1 lore raw

Quoted 10 lines · Shivani Bhardwaj

Add translation for NF Logging to nftables.

Examples:

$ sudo iptables-translate -A OUTPUT -j NFLOG --nflog-group 30
nft add rule ip filter OUTPUT counter log group 30

$ sudo iptables-translate -A FORWARD -j NFLOG --nflog-group 32 --nflog-prefix "Prefix 1.0"
nft add rule ip filter FORWARD counter log prefix \"Prefix 1.0\" log group 32

Hi Shivani,

I think that rule should translate to:
nft add rule ip filter FORWARD counter log prefix \"Prefix 1.0\" group 32

so, avoid using multiple 'log' keywords, which will load several nftables log expressions.

Quoted 6 lines

extensions/libxt_NFLOG.c +5 -0

+static void nflog_print_xlate(const struct xt_nflog_info *info,
+                             char *prefix, struct xt_buf *buf)
+{
+       if (info->prefix[0] != '\0')
+               xt_buf_add(buf, "%slog prefix \\\"%s\\\" ",

extensions/libxt_NFLOG.c static void NFLOG_save(const void *ip, const struct xt_entry_target *target) · line 103

Quoted 10 lines

extensions/libxt_NFLOG.c +10 -0

+                          prefix, info->prefix);
+       if (info->group)
+               xt_buf_add(buf, "%slog group %u ", prefix, info->group);
+       if (info->len)
+               xt_buf_add(buf, "%slog snaplen %u ", prefix, info->len);
+       if (info->threshold != XT_NFLOG_DEFAULT_THRESHOLD)
+               xt_buf_add(buf, "%slog queue-threshold %u ",
+                          prefix, info->threshold);
+}
+

You may revisit this function.

Signature · 5 lines

Arturo Borrero González
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Arturo Borrero Gonzalez

2015-12-22 12:48 UTC #2 lore raw

In reply to Shivani Bhardwaj

extensions/libxt_NFLOG.c static void NFLOG_save(const void *ip, const struct xt_entry_target *target) · line 96

Quoted 9 lines · Shivani Bhardwaj

extensions/libxt_NFLOG.c +8 -0

+static void nflog_print_xlate(const struct xt_nflog_info *info,
+                             char *prefix, struct xt_buf *buf)
+{
+       if (info->prefix[0] != '\0')
+               xt_buf_add(buf, "%slog prefix \\\"%s\\\" ",
+                          prefix, info->prefix);
+       if (info->group)
+               xt_buf_add(buf, "%slog group %u ", prefix, info->group);

if info->group is not set, you should probably default to 0, since this group info is mandatory in nftables to consider this logging the same type of NFLOG (ie, use nfnetlink_log).

For reference, see:
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/net/netfilter/nft_log.c#n67

Signature · 5 lines

Arturo Borrero González
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the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Pablo Neira Ayuso

maintainer

2015-12-22 17:01 UTC #3 lore raw

Quoted 15 lines · Arturo Borrero Gonzalez

extensions/libxt_NFLOG.c static void NFLOG_save(const void *ip, const struct xt_entry_target *target) · line 96
Quoted 9 lines · Shivani Bhardwaj
extensions/libxt_NFLOG.c +8 -0
+static void nflog_print_xlate(const struct xt_nflog_info *info,
+                             char *prefix, struct xt_buf *buf)
+{
+       if (info->prefix[0] != '\0')
+               xt_buf_add(buf, "%slog prefix \\\"%s\\\" ",
+                          prefix, info->prefix);
+       if (info->group)
+               xt_buf_add(buf, "%slog group %u ", prefix, info->group);
if info->group is not set, you should probably default to 0, since this group info is mandatory in nftables to consider this logging the same type of NFLOG (ie, use nfnetlink_log).

Quoted 2 lines

For reference, see:
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/net/netfilter/nft_log.c#n67

Thanks Arturo.

Please Shivani, address Arturo's feedback and send me an incremental patch to fix this.

Pablo Neira Ayuso

maintainer

2015-12-22 16:44 UTC #4 lore raw

In reply to Shivani Bhardwaj

Quoted 7 lines · Shivani Bhardwaj

Add translation for NF Logging to nftables.
Examples:
$ sudo iptables-translate -A OUTPUT -j NFLOG --nflog-group 30
nft add rule ip filter OUTPUT counter log group 30

Quoted 8 lines

$ sudo iptables-translate -A FORWARD -j NFLOG --nflog-group 32 --nflog-prefix "Prefix 1.0"
nft add rule ip filter FORWARD counter log prefix \"Prefix 1.0\" log group 32

$ sudo iptables-translate -I INPUT -j NFLOG --nflog-range 256
nft insert rule ip filter INPUT counter log snaplen 256

$ sudo iptables-translate -I INPUT -j NFLOG --nflog-threshold 25
nft insert rule ip filter INPUT counter log queue-threshold 25

Applied with changes.

Quoted 33 lines

Signed-off-by Shivani Bhardwaj <[email protected]>

---
 extensions/libxt_NFLOG.c | 28 +++++++++++++++++++++++++++-
 1 file changed, 27 insertions(+), 1 deletion(-)

extensions/libxt_NFLOG.c +12 -1

index 448576a..3d05ce0 100644
@@ -72,7 +72,7 @@ static void nflog_print(const struct xt_nflog_info *info, char *prefix)
 }
 
 static void NFLOG_print(const void *ip, const struct xt_entry_target *target,
-                        int numeric)
+			int numeric)
 {
 	const struct xt_nflog_info *info = (struct xt_nflog_info *)target->data;

@@ -86,6 +86,31 @@ static void NFLOG_save(const void *ip, const struct xt_entry_target *target)
 	nflog_print(info, "--");
 }
 
+static void nflog_print_xlate(const struct xt_nflog_info *info,
+			      char *prefix, struct xt_buf *buf)
+{
+	if (info->prefix[0] != '\0')
+		xt_buf_add(buf, "%slog prefix \\\"%s\\\" ",
+			   prefix, info->prefix);
+	if (info->group)
+		xt_buf_add(buf, "%slog group %u ", prefix, info->group);
+	if (info->len)
+		xt_buf_add(buf, "%slog snaplen %u ", prefix, info->len);
+	if (info->threshold != XT_NFLOG_DEFAULT_THRESHOLD)

extensions/libxt_NFLOG.c static void NFLOG_save(const void *ip, const struct xt_entry_target *target) · line 109

Quoted 10 lines

extensions/libxt_NFLOG.c +10 -0

+		xt_buf_add(buf, "%slog queue-threshold %u ",
+			   prefix, info->threshold);
+}
+
+static int NFLOG_xlate(const struct xt_entry_target *target,
+		       struct xt_buf *buf, int numeric)
+{
+	const struct xt_nflog_info *info = (struct xt_nflog_info *)target->data;
+
+	nflog_print_xlate(info, "", buf);

^^

This is always "", so we can get rid of this extra parameter.

I have fixed this here, no need to send v2.

Thanks.