Kuo-Lang Tseng et al: add ipv6 support

1 files changed, 136 insertions, 0 deletions

diff --git a/useful_functions.c b/useful_functions.c
index 131851a..1634f22 100644
--- a/useful_functions.c
+++ b/useful_functions.c
@@ -29,6 +29,10 @@
 #include <string.h>
 #include <stdlib.h>
 #include <getopt.h>
+#include <errno.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <arpa/inet.h>
 
 const unsigned char mac_type_unicast[ETH_ALEN] =   {0,0,0,0,0,0};
 const unsigned char msk_type_unicast[ETH_ALEN] =   {1,0,0,0,0,0};
@@ -244,6 +248,7 @@ void ebt_parse_ip_address(char *address, uint32_t *addr, uint32_t *msk)
 	*addr = *addr & *msk;
 }
 
+
 /* Transform the ip mask into a string ready for output. */
 char *ebt_mask_to_dotted(uint32_t mask)
 {
@@ -276,3 +281,134 @@ char *ebt_mask_to_dotted(uint32_t mask)
 
 	return buf;
 }
+
+/* Most of the following code is derived from iptables */
+static void
+in6addrcpy(struct in6_addr *dst, struct in6_addr *src)
+{
+    memcpy(dst, src, sizeof(struct in6_addr));
+}
+
+int string_to_number_ll(const char *s, unsigned long long min,
+            unsigned long long max, unsigned long long *ret)
+{
+    unsigned long long number;
+    char *end;
+
+    /* Handle hex, octal, etc. */
+    errno = 0;
+    number = strtoull(s, &end, 0);
+    if (*end == '\0' && end != s) {
+        /* we parsed a number, let's see if we want this */
+        if (errno != ERANGE && min <= number && (!max || number <= max)) {
+            *ret = number;
+            return 0;
+        }
+    }
+    return -1;
+}
+
+int string_to_number_l(const char *s, unsigned long min, unsigned long max,
+               unsigned long *ret)
+{
+    int result;
+    unsigned long long number;
+
+    result = string_to_number_ll(s, min, max, &number);
+    *ret = (unsigned long)number;
+
+    return result;
+}
+
+int string_to_number(const char *s, unsigned int min, unsigned int max,
+        unsigned int *ret)
+{
+    int result;
+    unsigned long number;
+
+    result = string_to_number_l(s, min, max, &number);
+    *ret = (unsigned int)number;
+
+    return result;
+}
+
+static struct in6_addr *
+numeric_to_addr(const char *num)
+{
+    static struct in6_addr ap;
+    int err;
+    if ((err=inet_pton(AF_INET6, num, &ap)) == 1)
+        return &ap;
+    return (struct in6_addr *)NULL;
+}
+
+static struct in6_addr *
+parse_ip6_mask(char *mask)
+{
+    static struct in6_addr maskaddr;
+    struct in6_addr *addrp;
+    unsigned int bits;
+
+    if (mask == NULL) {
+        /* no mask at all defaults to 128 bits */
+        memset(&maskaddr, 0xff, sizeof maskaddr);
+        return &maskaddr;
+    }
+    if ((addrp = numeric_to_addr(mask)) != NULL)
+        return addrp;
+    if (string_to_number(mask, 0, 128, &bits) == -1)
+		ebt_print_error("Invalid IPv6 Mask '%s' specified", mask);
+    if (bits != 0) {
+        char *p = (char *)&maskaddr;
+        memset(p, 0xff, bits / 8);
+        memset(p + (bits / 8) + 1, 0, (128 - bits) / 8);
+        p[bits / 8] = 0xff << (8 - (bits & 7));
+        return &maskaddr;
+    }
+
+    memset(&maskaddr, 0, sizeof maskaddr);
+    return &maskaddr;
+}
+
+/* Set the ipv6 mask and address. Callers should check ebt_errormsg[0].
+ * The string pointed to by address can be altered. */
+void ebt_parse_ip6_address(char *address, struct in6_addr *addr, 
+						   struct in6_addr *msk)
+{
+    struct in6_addr *tmp_addr;
+    char buf[256];
+    char *p;
+    int i;
+    int err;
+
+    strncpy(buf, address, sizeof(buf) - 1);
+	/* first the mask */
+    buf[sizeof(buf) - 1] = '\0';
+    if ((p = strrchr(buf, '/')) != NULL) {
+        *p = '\0';
+        tmp_addr = parse_ip6_mask(p + 1);
+    } else
+        tmp_addr = parse_ip6_mask(NULL);
+    in6addrcpy(msk, tmp_addr);
+
+    /* if a null mask is given, the name is ignored, like in "any/0" */
+    if (!memcmp(msk, &in6addr_any, sizeof(in6addr_any)))
+        strcpy(buf, "::");
+
+    if ((err=inet_pton(AF_INET6, buf, addr)) < 1) {
+		ebt_print_error("Invalid IPv6 Address '%s' specified", buf);
+		return;
+	}
+
+ 	for (i = 0; i < 4; i++)
+    	addr->in6_u.u6_addr32[i] &= msk->in6_u.u6_addr32[i];
+}
+
+/* Transform the ip6 addr into a string ready for output. */
+char *ebt_ip6_to_numeric(const struct in6_addr *addrp)
+{
+    /* 0000:0000:0000:0000:0000:000.000.000.000
+     * 0000:0000:0000:0000:0000:0000:0000:0000 */
+    static char buf[50+1];
+    return (char *)inet_ntop(AF_INET6, addrp, buf, sizeof(buf));
+}