extensions: libip6t_icmp6: Add translation to nft

PATCH Superseded Laura Garcia Liebana 2 participants 4 messages Mar 6, 2016 – Mar 7, 2016 netfilter

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Laura Garcia Liebana

author

2016-03-06 22:23 UTC #0 lore raw

PATCH v2 1/1 extensions: libip6t_icmp6: Add translation to nft

Add translation for icmpv6 to nftables. Not supported types in nftables
are: no-route, communication-prohibited, beyond-scope, address-unreachable, port-unreachable, failed-policy, reject-route, ttl-zero-during-transit, ttl-zero-during-reassembly, bad-header, unknown-header-type and unknown-option.

Examples:

$ ip6tables-translate -t filter -A INPUT -m icmp6 --icmpv6-type 1 -j LOG
nft add rule ip6 filter INPUT icmpv6 type destination-unreachable counter log level warn

$ ip6tables-translate -t filter -A INPUT -m icmp6 --icmpv6-type neighbour-advertisement -j LOG
nft add rule ip6 filter INPUT icmpv6 type nd-neighbor-advert counter log level warn

$ ip6tables-translate -t filter -A INPUT -m icmp6 ! --icmpv6-type packet-too-big -j LOG
nft add rule ip6 filter INPUT icmpv6 type != packet-too-big counter log level warn

Signed-off-by Laura Garcia Liebana <[email protected]>

---
v2:
- Detection of not supported types in nftables, as Shivani suggested.

 extensions/libip6t_icmp6.c | 53 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 53 insertions(+)

extensions/libip6t_icmp6.c +53 -0

index e183ce6..70f9c21 100644
@@ -222,6 +222,58 @@ static void icmp6_save(const void *ip, const struct xt_entry_match *match)
 		printf("/%u", icmpv6->code[0]);
 }
 
+static unsigned int type_xlate_print(struct xt_xlate *xl, unsigned int icmptype,
+			     unsigned int code_min, unsigned int code_max)
+{
+	unsigned int i;
+
+	if (code_min == code_max)
+		return 0;
+
+	switch (icmptype) {
+	case 133:
+		xt_xlate_add(xl, "nd-router-solicit");
+		break;
+	case 134:
+		xt_xlate_add(xl, "nd-router-advert");
+		break;
+	case 135:
+		xt_xlate_add(xl, "nd-neighbor-solicit");
+		break;
+	case 136:
+		xt_xlate_add(xl, "nd-neighbor-advert");
+		break;
+	case 137:
+		xt_xlate_add(xl, "nd-redirect");
+		break;
+	default:
+		for (i = 0; ARRAY_SIZE(icmpv6_codes); ++i)
+			if (icmpv6_codes[i].type == icmptype &&
+			    icmpv6_codes[i].code_min == code_min &&
+			    icmpv6_codes[i].code_max == code_max)
+				break;
+			xt_xlate_add(xl, icmpv6_codes[i].name);
+	}
+
+	return 1;
+}
+
+static int icmp6_xlate(const struct xt_entry_match *match, struct xt_xlate *xl,
+		       int numeric)
+{
+	const struct ip6t_icmp *info = (struct ip6t_icmp *)match->data;
+
+	xt_xlate_add(xl, "icmpv6 type%s ",
+		     (info->invflags & IP6T_ICMP_INV) ? " !=" : "");
+
+	if (!type_xlate_print(xl, info->type, info->code[0], info->code[1]))
+		return 0;
+
+	xt_xlate_add(xl, " ");
+
+	return 1;
+}
+
 static struct xtables_match icmp6_mt6_reg = {
 	.name 		= "icmp6",
 	.version 	= XTABLES_VERSION,

@@ -234,6 +286,7 @@ static struct xtables_match icmp6_mt6_reg = {
 	.save		= icmp6_save,
 	.x6_parse	= icmp6_parse,
 	.x6_options	= icmp6_opts,
+	.xlate		= icmp6_xlate,
 };
 
 void _init(void)

Signature · 1 line

2.7.0

Pablo Neira Ayuso

maintainer

2016-03-07 17:11 UTC #1 lore raw

Quoted 47 lines · Laura Garcia Liebana

Examples:

$ ip6tables-translate -t filter -A INPUT -m icmp6 --icmpv6-type 1 -j LOG
nft add rule ip6 filter INPUT icmpv6 type destination-unreachable counter log level warn

$ ip6tables-translate -t filter -A INPUT -m icmp6 --icmpv6-type neighbour-advertisement -j LOG
nft add rule ip6 filter INPUT icmpv6 type nd-neighbor-advert counter log level warn

$ ip6tables-translate -t filter -A INPUT -m icmp6 ! --icmpv6-type packet-too-big -j LOG
nft add rule ip6 filter INPUT icmpv6 type != packet-too-big counter log level warn

Signed-off-by Laura Garcia Liebana <[email protected]>

---
v2:
- Detection of not supported types in nftables, as Shivani suggested.

 extensions/libip6t_icmp6.c | 53 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 53 insertions(+)

extensions/libip6t_icmp6.c +14 -0

index e183ce6..70f9c21 100644
@@ -222,6 +222,58 @@ static void icmp6_save(const void *ip, const struct xt_entry_match *match)
 		printf("/%u", icmpv6->code[0]);
 }
 
+static unsigned int type_xlate_print(struct xt_xlate *xl, unsigned int icmptype,
+			     unsigned int code_min, unsigned int code_max)
+{
+	unsigned int i;
+
+	if (code_min == code_max)
+		return 0;
+
+	switch (icmptype) {
+	case 133:
+		xt_xlate_add(xl, "nd-router-solicit");
+		break;
+	case 134:
+		xt_xlate_add(xl, "nd-router-advert");

extensions/libip6t_icmp6.c static void icmp6_save(const void *ip, const struct xt_entry_match *match) · line 248

Quoted 10 lines

extensions/libip6t_icmp6.c +10 -0

+		break;
+	case 135:
+		xt_xlate_add(xl, "nd-neighbor-solicit");
+		break;
+	case 136:
+		xt_xlate_add(xl, "nd-neighbor-advert");
+		break;
+	case 137:
+		xt_xlate_add(xl, "nd-redirect");
+		break;

Could you generalize this code a bit?

#define XT_ICMPV6_TYPE(type) (ND_ROUTER_SOLICIT - type)

static const char *icmp6_type_xlate_array[] = {
[XT_ICMPV6_TYPE(ND_ROUTER_SOLICIT))] = "nd-router-solicit",
[XT_ICMPV6_TYPE(ND_ROUTER_ADVERT)] = "nd-router-advert",
...
[XT_ICMPV6_TYPE(ND_REDIRECT)] = "nd-redirect",
};

static const char *icmp6_type_xlate(unsigned int type)

{
        unsigned type

        if (type < ND_ROUTER_SOLICIT || type > ND_REDIRECT))
                return NULL;

        return icmp6_type_xlate_array[XT_ICMPV6_TYPE(type)];
}

Then, from type_xlate_print() use this icmp6_type_xlate().

extensions/libip6t_icmp6.c static void icmp6_save(const void *ip, const struct xt_entry_match *match) · line 250

Quoted 2 lines

extensions/libip6t_icmp6.c +2 -0

+	default:
+		for (i = 0; ARRAY_SIZE(icmpv6_codes); ++i)

BTW, missing opening bracket here

extensions/libip6t_icmp6.c static void icmp6_save(const void *ip, const struct xt_entry_match *match) · line 255

Quoted 5 lines

extensions/libip6t_icmp6.c +5 -0

+			if (icmpv6_codes[i].type == icmptype &&
+			    icmpv6_codes[i].code_min == code_min &&
+			    icmpv6_codes[i].code_max == code_max)
+				break;
+			xt_xlate_add(xl, icmpv6_codes[i].name);

and closing bracket here '}'

BTW, do you really need this code now that we just skip when we get an icmp code?

Quoted 35 lines

extensions/libip6t_icmp6.c +22 -0

+	}
+
+	return 1;
+}
+
+static int icmp6_xlate(const struct xt_entry_match *match, struct xt_xlate *xl,
+		       int numeric)
+{
+	const struct ip6t_icmp *info = (struct ip6t_icmp *)match->data;
+
+	xt_xlate_add(xl, "icmpv6 type%s ",
+		     (info->invflags & IP6T_ICMP_INV) ? " !=" : "");
+
+	if (!type_xlate_print(xl, info->type, info->code[0], info->code[1]))
+		return 0;
+
+	xt_xlate_add(xl, " ");
+
+	return 1;
+}
+
 static struct xtables_match icmp6_mt6_reg = {
 	.name 		= "icmp6",
 	.version 	= XTABLES_VERSION,

@@ -234,6 +286,7 @@ static struct xtables_match icmp6_mt6_reg = {
 	.save		= icmp6_save,
 	.x6_parse	= icmp6_parse,
 	.x6_options	= icmp6_opts,
+	.xlate		= icmp6_xlate,
 };
 
 void _init(void)

Signature · 1 line

2.7.0

Laura Garcia

author

2016-03-07 18:08 UTC #2 lore raw

Quoted 80 lines · Pablo Neira Ayuso

Quoted 47 lines · Laura Garcia Liebana
Add translation for icmpv6 to nftables. Not supported types in nftables
are: no-route, communication-prohibited, beyond-scope, address-unreachable, port-unreachable, failed-policy, reject-route, ttl-zero-during-transit, ttl-zero-during-reassembly, bad-header, unknown-header-type and unknown-option.
Examples:
$ ip6tables-translate -t filter -A INPUT -m icmp6 --icmpv6-type 1 -j LOG
nft add rule ip6 filter INPUT icmpv6 type destination-unreachable counter log level warn
$ ip6tables-translate -t filter -A INPUT -m icmp6 --icmpv6-type neighbour-advertisement -j LOG
nft add rule ip6 filter INPUT icmpv6 type nd-neighbor-advert counter log level warn
$ ip6tables-translate -t filter -A INPUT -m icmp6 ! --icmpv6-type packet-too-big -j LOG
nft add rule ip6 filter INPUT icmpv6 type != packet-too-big counter log level warn
Signed-off-by Laura Garcia Liebana <[email protected]>
---
v2:
- Detection of not supported types in nftables, as Shivani suggested.
 extensions/libip6t_icmp6.c | 53 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 53 insertions(+)
extensions/libip6t_icmp6.c +14 -0
index e183ce6..70f9c21 100644
@@ -222,6 +222,58 @@ static void icmp6_save(const void *ip, const struct xt_entry_match *match)
 		printf("/%u", icmpv6->code[0]);
 }
 
+static unsigned int type_xlate_print(struct xt_xlate *xl, unsigned int icmptype,
+			     unsigned int code_min, unsigned int code_max)
+{
+	unsigned int i;
+
+	if (code_min == code_max)
+		return 0;
+
+	switch (icmptype) {
+	case 133:
+		xt_xlate_add(xl, "nd-router-solicit");
+		break;
+	case 134:
+		xt_xlate_add(xl, "nd-router-advert");
extensions/libip6t_icmp6.c static void icmp6_save(const void *ip, const struct xt_entry_match *match) · line 248
Quoted 10 lines
extensions/libip6t_icmp6.c +10 -0
+		break;
+	case 135:
+		xt_xlate_add(xl, "nd-neighbor-solicit");
+		break;
+	case 136:
+		xt_xlate_add(xl, "nd-neighbor-advert");
+		break;
+	case 137:
+		xt_xlate_add(xl, "nd-redirect");
+		break;
Could you generalize this code a bit?
#define XT_ICMPV6_TYPE(type) (ND_ROUTER_SOLICIT - type)
static const char *icmp6_type_xlate_array[] = {
[XT_ICMPV6_TYPE(ND_ROUTER_SOLICIT))] = "nd-router-solicit",
[XT_ICMPV6_TYPE(ND_ROUTER_ADVERT)] = "nd-router-advert",
...
[XT_ICMPV6_TYPE(ND_REDIRECT)] = "nd-redirect",
};
static const char *icmp6_type_xlate(unsigned int type)
{
        unsigned type

        if (type < ND_ROUTER_SOLICIT || type > ND_REDIRECT))
                return NULL;

        return icmp6_type_xlate_array[XT_ICMPV6_TYPE(type)];
}

Quoted 2 lines

Then, from type_xlate_print() use this icmp6_type_xlate().

Quoted 13 lines

extensions/libip6t_icmp6.c static void icmp6_save(const void *ip, const struct xt_entry_match *match) · line 250
Quoted 2 lines
extensions/libip6t_icmp6.c +2 -0
+	default:
+		for (i = 0; ARRAY_SIZE(icmpv6_codes); ++i)
                                                           ^
BTW, missing opening bracket here
extensions/libip6t_icmp6.c static void icmp6_save(const void *ip, const struct xt_entry_match *match) · line 255
Quoted 5 lines
extensions/libip6t_icmp6.c +5 -0
+			if (icmpv6_codes[i].type == icmptype &&
+			    icmpv6_codes[i].code_min == code_min &&
+			    icmpv6_codes[i].code_max == code_max)
+				break;
+			xt_xlate_add(xl, icmpv6_codes[i].name);
and closing bracket here '}'

Quoted 3 lines

BTW, do you really need this code now that we just skip when we get an icmp code?

Same thing here, the brackets are not needed. It's only a indentation problem in the function xt_xlate_add.

This piece is not for icmp codes, but icmp types. We're ensuring that at the begining of the function:

+ if (code_min == code_max)
+ return 0;

Quoted 35 lines

extensions/libip6t_icmp6.c +22 -0

+	}
+
+	return 1;
+}
+
+static int icmp6_xlate(const struct xt_entry_match *match, struct xt_xlate *xl,
+		       int numeric)
+{
+	const struct ip6t_icmp *info = (struct ip6t_icmp *)match->data;
+
+	xt_xlate_add(xl, "icmpv6 type%s ",
+		     (info->invflags & IP6T_ICMP_INV) ? " !=" : "");
+
+	if (!type_xlate_print(xl, info->type, info->code[0], info->code[1]))
+		return 0;
+
+	xt_xlate_add(xl, " ");
+
+	return 1;
+}
+
 static struct xtables_match icmp6_mt6_reg = {
 	.name 		= "icmp6",
 	.version 	= XTABLES_VERSION,

@@ -234,6 +286,7 @@ static struct xtables_match icmp6_mt6_reg = {
 	.save		= icmp6_save,
 	.x6_parse	= icmp6_parse,
 	.x6_options	= icmp6_opts,
+	.xlate		= icmp6_xlate,
 };
 
 void _init(void)

Signature · 1 line

2.7.0

Pablo Neira Ayuso

maintainer

2016-03-07 18:25 UTC #3 lore raw

Quoted 39 lines · Laura Garcia

Quoted 20 lines · Pablo Neira Ayuso
#define XT_ICMPV6_TYPE(type) (ND_ROUTER_SOLICIT - type)
static const char *icmp6_type_xlate_array[] = {
[XT_ICMPV6_TYPE(ND_ROUTER_SOLICIT))] = "nd-router-solicit",
[XT_ICMPV6_TYPE(ND_ROUTER_ADVERT)] = "nd-router-advert",
...
[XT_ICMPV6_TYPE(ND_REDIRECT)] = "nd-redirect",
};
static const char *icmp6_type_xlate(unsigned int type)
{
        unsigned type

        if (type < ND_ROUTER_SOLICIT || type > ND_REDIRECT))
                return NULL;

        return icmp6_type_xlate_array[XT_ICMPV6_TYPE(type)];
}
Quoted 2 lines
Then, from type_xlate_print() use this icmp6_type_xlate().
Ok
Quoted 13 lines
extensions/libip6t_icmp6.c static void icmp6_save(const void *ip, const struct xt_entry_match *match) · line 250
Quoted 2 lines
extensions/libip6t_icmp6.c +2 -0
+	default:
+		for (i = 0; ARRAY_SIZE(icmpv6_codes); ++i)
                                                           ^
BTW, missing opening bracket here
extensions/libip6t_icmp6.c static void icmp6_save(const void *ip, const struct xt_entry_match *match) · line 255
Quoted 5 lines
extensions/libip6t_icmp6.c +5 -0
+			if (icmpv6_codes[i].type == icmptype &&
+			    icmpv6_codes[i].code_min == code_min &&
+			    icmpv6_codes[i].code_max == code_max)
+				break;
+			xt_xlate_add(xl, icmpv6_codes[i].name);
and closing bracket here '}'

Quoted 6 lines

Quoted 3 lines
BTW, do you really need this code now that we just skip when we get an icmp code?
Same thing here, the brackets are not needed. It's only a indentation problem in the function xt_xlate_add.

Ok, thanks for explaining.

Please, send a v3 with the proposed changes above and resubmit. Thanks.