libxtables: Integrate getethertype.c from xtables core

This moves getethertype.c into libxtables so that both extensions and
xtables-nft-multi may use the implementations therein. New users are
libebt_arp and libebt_vlan which drop their own duplicated
implementations of getethertypebyname() for the shared one.

This change originated from a covscan report of extensions'
implementations not checking fopen() return value which should be
implicitly fixed by this as well.

Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Florian Westphal <fw@strlen.de>

5 files changed, 4 insertions, 144 deletions

diff --git a/extensions/libebt_arp.c b/extensions/libebt_arp.c
index 45fc8d73..dc8e306a 100644
--- a/extensions/libebt_arp.c
+++ b/extensions/libebt_arp.c
@@ -209,76 +209,6 @@ static int brarp_get_mac_and_mask(const char *from, unsigned char *to, unsigned
 	return 0;
 }
 
-static struct ethertypeent *brarp_getethertypeent(FILE *etherf, const char *name)
-{
-	static struct ethertypeent et_ent;
-	char *e, *found_name;
-	char line[1024];
-
-	while ((e = fgets(line, sizeof(line), etherf))) {
-		char *endptr, *cp;
-
-		if (*e == '#')
-			continue;
-
-		cp = strpbrk(e, "#\n");
-		if (cp == NULL)
-			continue;
-		*cp = '\0';
-		found_name = e;
-
-		cp = strpbrk(e, " \t");
-		if (cp == NULL)
-			continue;
-
-		*cp++ = '\0';
-		while (*cp == ' ' || *cp == '\t')
-			cp++;
-		e = strpbrk(cp, " \t");
-		if (e != NULL)
-			*e++ = '\0';
-
-		et_ent.e_ethertype = strtol(cp, &endptr, 16);
-		if (*endptr != '\0' ||
-		    (et_ent.e_ethertype < ETH_ZLEN || et_ent.e_ethertype > 0xFFFF))
-			continue;
-
-		if (strcasecmp(found_name, name) == 0)
-			return (&et_ent);
-
-		if (e != NULL) {
-			cp = e;
-			while (cp && *cp) {
-				if (*cp == ' ' || *cp == '\t') {
-					cp++;
-					continue;
-				}
-				e = cp;
-				cp = strpbrk(cp, " \t");
-				if (cp != NULL)
-					*cp++ = '\0';
-				if (strcasecmp(e, name) == 0)
-					return (&et_ent);
-				e = cp;
-			}
-		}
-	}
-
-	return NULL;
-}
-
-static struct ethertypeent *brarp_getethertypebyname(const char *name)
-{
-	struct ethertypeent *e;
-	FILE *etherf;
-
-	etherf = fopen(_PATH_ETHERTYPES, "r");
-
-	e = brarp_getethertypeent(etherf, name);
-	fclose(etherf);
-	return (e);
-}
-
 static int
 brarp_parse(int c, char **argv, int invert, unsigned int *flags,
 	    const void *entry, struct xt_entry_match **match)
@@ -334,7 +264,7 @@ brarp_parse(int c, char **argv, int invert, unsigned int *flags,
 		if (i < 0 || i >= (0x1 << 16) || *end !='\0') {
 			struct ethertypeent *ent;
 
-			ent = brarp_getethertypebyname(argv[optind - 1]);
+			ent = getethertypebyname(argv[optind - 1]);
 			if (!ent)
 				xtables_error(PARAMETER_PROBLEM, "Problem with specified ARP "
 								 "protocol type");
diff --git a/extensions/libebt_vlan.c b/extensions/libebt_vlan.c
index 4e2ea0fc..52cc99fa 100644
--- a/extensions/libebt_vlan.c
+++ b/extensions/libebt_vlan.c
@@ -50,76 +50,6 @@ static void brvlan_print_help(void)
 "--vlan-encap [!] encap : Encapsulated frame protocol (hexadecimal or name)\n");
 }
 
-static struct ethertypeent *vlan_getethertypeent(FILE *etherf, const char *name)
-{
-	static struct ethertypeent et_ent;
-	char *e, *found_name;
-	char line[1024];
-
-	while ((e = fgets(line, sizeof(line), etherf))) {
-		char *endptr, *cp;
-
-		if (*e == '#')
-			continue;
-
-		cp = strpbrk(e, "#\n");
-		if (cp == NULL)
-			continue;
-		*cp = '\0';
-		found_name = e;
-
-		cp = strpbrk(e, " \t");
-		if (cp == NULL)
-			continue;
-
-		*cp++ = '\0';
-		while (*cp == ' ' || *cp == '\t')
-			cp++;
-		e = strpbrk(cp, " \t");
-		if (e != NULL)
-			*e++ = '\0';
-
-		et_ent.e_ethertype = strtol(cp, &endptr, 16);
-		if (*endptr != '\0' ||
-		    (et_ent.e_ethertype < ETH_ZLEN || et_ent.e_ethertype > 0xFFFF))
-			continue; // skip invalid etherproto type entry
-
-		if (strcasecmp(found_name, name) == 0)
-			return (&et_ent);
-
-		if (e != NULL) {
-			cp = e;
-			while (cp && *cp) {
-				if (*cp == ' ' || *cp == '\t') {
-					cp++;
-					continue;
-				}
-				e = cp;
-				cp = strpbrk(cp, " \t");
-				if (cp != NULL)
-					*cp++ = '\0';
-				if (strcasecmp(e, name) == 0)
-					return (&et_ent);
-				e = cp;
-			}
-		}
-	}
-
-	return NULL;
-}
-
-static struct ethertypeent *brvlan_getethertypebyname(const char *name)
-{
-	struct ethertypeent *e;
-	FILE *etherf;
-
-	etherf = fopen(_PATH_ETHERTYPES, "r");
-
-	e = vlan_getethertypeent(etherf, name);
-	fclose(etherf);
-	return (e);
-}
-
 static int
 brvlan_parse(int c, char **argv, int invert, unsigned int *flags,
 	       const void *entry, struct xt_entry_match **match)
@@ -156,7 +86,7 @@ brvlan_parse(int c, char **argv, int invert, unsigned int *flags,
 			vlaninfo->invflags |= EBT_VLAN_ENCAP;
 		local.encap = strtoul(optarg, &end, 16);
 		if (*end != '\0') {
-			ethent = brvlan_getethertypebyname(optarg);
+			ethent = getethertypebyname(optarg);
 			if (ethent == NULL)
 				xtables_error(PARAMETER_PROBLEM, "Unknown --vlan-encap value ('%s')", optarg);
 			local.encap = ethent->e_ethertype;
diff --git a/iptables/Makefile.am b/iptables/Makefile.am
index d0218ddc..581dc32b 100644
--- a/iptables/Makefile.am
+++ b/iptables/Makefile.am
@@ -43,7 +43,7 @@ xtables_nft_multi_SOURCES += xtables-save.c xtables-restore.c \
 				nft-shared.c nft-ipv4.c nft-ipv6.c nft-arp.c \
 				xtables-monitor.c \
 				xtables-arp-standalone.c xtables-arp.c \
-				getethertype.c nft-bridge.c \
+				nft-bridge.c \
 				xtables-eb-standalone.c xtables-eb.c \
 				xtables-eb-translate.c \
 				xtables-translate.c
diff --git a/libxtables/Makefile.am b/libxtables/Makefile.am
index 4267cb5f..8ff6b0ca 100644
--- a/libxtables/Makefile.am
+++ b/libxtables/Makefile.am
@@ -4,7 +4,7 @@ AM_CFLAGS   = ${regular_CFLAGS}
 AM_CPPFLAGS = ${regular_CPPFLAGS} -I${top_builddir}/include -I${top_srcdir}/include -I${top_srcdir}/iptables ${kinclude_CPPFLAGS}
 
 lib_LTLIBRARIES       = libxtables.la
-libxtables_la_SOURCES = xtables.c xtoptions.c
+libxtables_la_SOURCES = xtables.c xtoptions.c getethertype.c
 libxtables_la_LDFLAGS = -version-info ${libxtables_vcurrent}:0:${libxtables_vage}
 libxtables_la_LIBADD  =
 if ENABLE_STATIC
diff --git a/iptables/getethertype.c b/libxtables/getethertype.c
index 027ef4ad..027ef4ad 100644
--- a/iptables/getethertype.c
+++ b/libxtables/getethertype.c