icmp: split icmp type printing to header file

libebt_ip will get icmp support soon, unify icmp name
mapping a bit so we can re-use this code from libebt_ip.c.

It doesn't seem to be too useful to move to libxtables
(as its icmp specific), so add a hedaer file for this to reduce
copy & paste needs.

Signed-off-by: Florian Westphal <fw@strlen.de>

3 files changed, 35 insertions, 58 deletions

diff --git a/extensions/libip6t_icmp6.c b/extensions/libip6t_icmp6.c
index 37c2bcb8..45a71875 100644
--- a/extensions/libip6t_icmp6.c
+++ b/extensions/libip6t_icmp6.c
@@ -6,17 +6,13 @@
 #include <linux/netfilter_ipv6/ip6_tables.h>
 #include <netinet/icmp6.h>
 
+#include "libxt_icmp.h"
+
 enum {
 	O_ICMPV6_TYPE = 0,
 };
 
-struct icmpv6_names {
-	const char *name;
-	uint8_t type;
-	uint8_t code_min, code_max;
-};
-
-static const struct icmpv6_names icmpv6_codes[] = {
+static const struct xt_icmp_names icmpv6_codes[] = {
 	{ "destination-unreachable", 1, 0, 0xFF },
 	{   "no-route", 1, 0, 0 },
 	{   "communication-prohibited", 1, 1, 1 },
@@ -58,34 +54,14 @@ static const struct icmpv6_names icmpv6_codes[] = {
 
 };
 
-static void
-print_icmpv6types(void)
-{
-	unsigned int i;
-	printf("Valid ICMPv6 Types:");
-
-	for (i = 0; i < ARRAY_SIZE(icmpv6_codes); ++i) {
-		if (i && icmpv6_codes[i].type == icmpv6_codes[i-1].type) {
-			if (icmpv6_codes[i].code_min == icmpv6_codes[i-1].code_min
-			    && (icmpv6_codes[i].code_max
-				== icmpv6_codes[i-1].code_max))
-				printf(" (%s)", icmpv6_codes[i].name);
-			else
-				printf("\n   %s", icmpv6_codes[i].name);
-		}
-		else
-			printf("\n%s", icmpv6_codes[i].name);
-	}
-	printf("\n");
-}
-
 static void icmp6_help(void)
 {
 	printf(
 "icmpv6 match options:\n"
 "[!] --icmpv6-type typename	match icmpv6 type\n"
 "				(or numeric type or type/code)\n");
-	print_icmpv6types();
+	printf("Valid ICMPv6 Types:");
+	xt_print_icmp_types(icmpv6_codes, ARRAY_SIZE(icmpv6_codes));
 }
 
 static const struct xt_option_entry icmp6_opts[] = {
diff --git a/extensions/libipt_icmp.c b/extensions/libipt_icmp.c
index 680a5b0c..54189976 100644
--- a/extensions/libipt_icmp.c
+++ b/extensions/libipt_icmp.c
@@ -5,6 +5,8 @@
 #include <limits.h> /* INT_MAX in ip6_tables.h */
 #include <linux/netfilter_ipv4/ip_tables.h>
 
+#include "libxt_icmp.h"
+
 /* special hack for icmp-type 'any': 
  * Up to kernel <=2.4.20 the problem was:
  * '-p icmp ' matches all icmp packets
@@ -17,13 +19,7 @@ enum {
 	O_ICMP_TYPE = 0,
 };
 
-struct icmp_names {
-	const char *name;
-	uint8_t type;
-	uint8_t code_min, code_max;
-};
-
-static const struct icmp_names icmp_codes[] = {
+static const struct xt_icmp_names icmp_codes[] = {
 	{ "any", 0xFF, 0, 0xFF },
 	{ "echo-reply", 0, 0, 0xFF },
 	/* Alias */ { "pong", 0, 0, 0xFF },
@@ -78,34 +74,14 @@ static const struct icmp_names icmp_codes[] = {
 	{ "address-mask-reply", 18, 0, 0xFF }
 };
 
-static void
-print_icmptypes(void)
-{
-	unsigned int i;
-	printf("Valid ICMP Types:");
-
-	for (i = 0; i < ARRAY_SIZE(icmp_codes); ++i) {
-		if (i && icmp_codes[i].type == icmp_codes[i-1].type) {
-			if (icmp_codes[i].code_min == icmp_codes[i-1].code_min
-			    && (icmp_codes[i].code_max
-				== icmp_codes[i-1].code_max))
-				printf(" (%s)", icmp_codes[i].name);
-			else
-				printf("\n   %s", icmp_codes[i].name);
-		}
-		else
-			printf("\n%s", icmp_codes[i].name);
-	}
-	printf("\n");
-}
-
 static void icmp_help(void)
 {
 	printf(
 "icmp match options:\n"
 "[!] --icmp-type typename	match icmp type\n"
 "[!] --icmp-type type[/code]	(or numeric type or type/code)\n");
-	print_icmptypes();
+	printf("Valid ICMP Types:");
+	xt_print_icmp_types(icmp_codes, ARRAY_SIZE(icmp_codes));
 }
 
 static const struct xt_option_entry icmp_opts[] = {
diff --git a/extensions/libxt_icmp.h b/extensions/libxt_icmp.h
new file mode 100644
index 00000000..5820206e
--- /dev/null
+++ b/extensions/libxt_icmp.h
@@ -0,0 +1,25 @@
+struct xt_icmp_names {
+	const char *name;
+	uint8_t type;
+	uint8_t code_min, code_max;
+};
+
+static void xt_print_icmp_types(const struct xt_icmp_names *icmp_codes,
+				unsigned int n_codes)
+{
+	unsigned int i;
+
+	for (i = 0; i < n_codes; ++i) {
+		if (i && icmp_codes[i].type == icmp_codes[i-1].type) {
+			if (icmp_codes[i].code_min == icmp_codes[i-1].code_min
+			    && (icmp_codes[i].code_max
+				== icmp_codes[i-1].code_max))
+				printf(" (%s)", icmp_codes[i].name);
+			else
+				printf("\n   %s", icmp_codes[i].name);
+		}
+		else
+			printf("\n%s", icmp_codes[i].name);
+	}
+	printf("\n");
+}