CONTRIB: ip6range: add a network IPv6 range to mask converter
It can be used to convert some Maxmind geolocation IPv6 lists using the
CVS format to IPv6 networks format.
diff --git a/contrib/ip6range/ip6range.c b/contrib/ip6range/ip6range.c
new file mode 100644
index 0000000..293e7d2
--- /dev/null
+++ b/contrib/ip6range/ip6range.c
@@ -0,0 +1,396 @@
+/*
+ * network range to IP+mask converter
+ *
+ * Copyright 2011-2012 Willy Tarreau <w@1wt.eu>
+ *
+ * This program reads lines starting by two IP addresses and outputs them with
+ * the two IP addresses replaced by a netmask covering the range between these
+ * IPs (inclusive). When multiple ranges are needed, as many lines are emitted.
+ * The IP addresses may be delimited by spaces, tabs or commas. Quotes are
+ * stripped, and lines beginning with a sharp character ('#') are ignored. The
+ * IP addresses may be either in the dotted format or represented as a 32-bit
+ * integer value in network byte order.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <arpa/inet.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define MAXLINE 1024
+
+static inline void in6_bswap(struct in6_addr *a)
+{
+ a->in6_u.u6_addr32[0] = ntohl(a->in6_u.u6_addr32[0]);
+ a->in6_u.u6_addr32[1] = ntohl(a->in6_u.u6_addr32[1]);
+ a->in6_u.u6_addr32[2] = ntohl(a->in6_u.u6_addr32[2]);
+ a->in6_u.u6_addr32[3] = ntohl(a->in6_u.u6_addr32[3]);
+}
+
+/* returns a string version of an IPv6 address in host order */
+static const char *get_ipv6_addr(struct in6_addr *addr)
+{
+ struct in6_addr a;
+ static char out[INET6_ADDRSTRLEN + 1];
+
+ memcpy(&a, addr, sizeof(struct in6_addr));
+ in6_bswap(&a);
+ return inet_ntop(AF_INET6, &a, out, INET6_ADDRSTRLEN + 1);
+}
+
+static const char *get_addr(struct in6_addr *addr)
+{
+ static char out[50];
+ snprintf(out, 50, "%08x:%08x:%08x:%08x",
+ addr->in6_u.u6_addr32[0],
+ addr->in6_u.u6_addr32[1],
+ addr->in6_u.u6_addr32[2],
+ addr->in6_u.u6_addr32[3]);
+ return out;
+}
+
+/* a <= b */
+static inline int a_le_b(struct in6_addr *a, struct in6_addr *b)
+{
+ if (a->in6_u.u6_addr32[0] < b->in6_u.u6_addr32[0]) return 1;
+ if (a->in6_u.u6_addr32[0] > b->in6_u.u6_addr32[0]) return 0;
+ if (a->in6_u.u6_addr32[1] < b->in6_u.u6_addr32[1]) return 1;
+ if (a->in6_u.u6_addr32[1] > b->in6_u.u6_addr32[1]) return 0;
+ if (a->in6_u.u6_addr32[2] < b->in6_u.u6_addr32[2]) return 1;
+ if (a->in6_u.u6_addr32[2] > b->in6_u.u6_addr32[2]) return 0;
+ if (a->in6_u.u6_addr32[3] < b->in6_u.u6_addr32[3]) return 1;
+ if (a->in6_u.u6_addr32[3] > b->in6_u.u6_addr32[3]) return 0;
+ return 1;
+}
+
+/* a == b */
+static inline int a_eq_b(struct in6_addr *a, struct in6_addr *b)
+{
+ if (a->in6_u.u6_addr32[0] != b->in6_u.u6_addr32[0]) return 0;
+ if (a->in6_u.u6_addr32[1] != b->in6_u.u6_addr32[1]) return 0;
+ if (a->in6_u.u6_addr32[2] != b->in6_u.u6_addr32[2]) return 0;
+ if (a->in6_u.u6_addr32[3] != b->in6_u.u6_addr32[3]) return 0;
+ return 1;
+}
+
+/* a > b */
+static inline int a_gt_b(struct in6_addr *a, struct in6_addr *b)
+{
+ if (a->in6_u.u6_addr32[0] > b->in6_u.u6_addr32[0]) return 1;
+ if (a->in6_u.u6_addr32[0] < b->in6_u.u6_addr32[0]) return 0;
+ if (a->in6_u.u6_addr32[1] > b->in6_u.u6_addr32[1]) return 1;
+ if (a->in6_u.u6_addr32[1] < b->in6_u.u6_addr32[1]) return 0;
+ if (a->in6_u.u6_addr32[2] > b->in6_u.u6_addr32[2]) return 1;
+ if (a->in6_u.u6_addr32[2] < b->in6_u.u6_addr32[2]) return 0;
+ if (a->in6_u.u6_addr32[3] > b->in6_u.u6_addr32[3]) return 1;
+ if (a->in6_u.u6_addr32[3] < b->in6_u.u6_addr32[3]) return 0;
+ return 0;
+}
+
+/* ( 1 << m ) - 1 -> r */
+static inline struct in6_addr *hmask(unsigned int b, struct in6_addr *r)
+{
+
+ if (b < 32) {
+ r->in6_u.u6_addr32[3] = (1 << b) - 1;
+ r->in6_u.u6_addr32[2] = 0;
+ r->in6_u.u6_addr32[1] = 0;
+ r->in6_u.u6_addr32[0] = 0;
+ }
+ else if (b < 64) {
+ r->in6_u.u6_addr32[3] = 0xffffffff;
+ r->in6_u.u6_addr32[2] = (1 << (b - 32)) - 1;
+ r->in6_u.u6_addr32[1] = 0;
+ r->in6_u.u6_addr32[0] = 0;
+ }
+ else if (b < 96) {
+ r->in6_u.u6_addr32[3] = 0xffffffff;
+ r->in6_u.u6_addr32[2] = 0xffffffff;
+ r->in6_u.u6_addr32[1] = (1 << (b - 64)) - 1;
+ r->in6_u.u6_addr32[0] = 0;
+ }
+ else if (b < 128) {
+ r->in6_u.u6_addr32[3] = 0xffffffff;
+ r->in6_u.u6_addr32[2] = 0xffffffff;
+ r->in6_u.u6_addr32[1] = 0xffffffff;
+ r->in6_u.u6_addr32[0] = (1 << (b - 96)) - 1;
+ }
+ else {
+ r->in6_u.u6_addr32[3] = 0xffffffff;
+ r->in6_u.u6_addr32[2] = 0xffffffff;
+ r->in6_u.u6_addr32[1] = 0xffffffff;
+ r->in6_u.u6_addr32[0] = 0xffffffff;
+ }
+ return r;
+}
+
+/* 1 << b -> r */
+static inline struct in6_addr *one_ls_b(unsigned int b, struct in6_addr *r)
+{
+ if (b < 32) {
+ r->in6_u.u6_addr32[3] = 1 << b;
+ r->in6_u.u6_addr32[2] = 0;
+ r->in6_u.u6_addr32[1] = 0;
+ r->in6_u.u6_addr32[0] = 0;
+ }
+ else if (b < 64) {
+ r->in6_u.u6_addr32[3] = 0;
+ r->in6_u.u6_addr32[2] = 1 << (b - 32);
+ r->in6_u.u6_addr32[1] = 0;
+ r->in6_u.u6_addr32[0] = 0;
+ }
+ else if (b < 96) {
+ r->in6_u.u6_addr32[3] = 0;
+ r->in6_u.u6_addr32[2] = 0;
+ r->in6_u.u6_addr32[1] = 1 << (b - 64);
+ r->in6_u.u6_addr32[0] = 0;
+ }
+ else if (b < 128) {
+ r->in6_u.u6_addr32[3] = 0;
+ r->in6_u.u6_addr32[2] = 0;
+ r->in6_u.u6_addr32[1] = 0;
+ r->in6_u.u6_addr32[0] = 1 << (b - 96);
+ }
+ else {
+ r->in6_u.u6_addr32[3] = 0;
+ r->in6_u.u6_addr32[2] = 0;
+ r->in6_u.u6_addr32[1] = 0;
+ r->in6_u.u6_addr32[0] = 0;
+ }
+ return r;
+}
+
+/* a + b -> r */
+static inline struct in6_addr *a_plus_b(struct in6_addr *a, struct in6_addr *b, struct in6_addr *r)
+{
+ unsigned long long int c = 0;
+ int i;
+
+ for (i=3; i>=0; i--) {
+ c = (unsigned long long int)a->in6_u.u6_addr32[i] +
+ (unsigned long long int)b->in6_u.u6_addr32[i] + c;
+ r->in6_u.u6_addr32[i] = c;
+ c >>= 32;
+ }
+
+ return r;
+}
+
+/* a - b -> r */
+static inline struct in6_addr *a_minus_b(struct in6_addr *a, struct in6_addr *b, struct in6_addr *r)
+{
+ signed long long int c = 0;
+ signed long long int d;
+ int i;
+
+ /* Check sign. Return 0xff..ff (-1) if the result is less than 0. */
+ if (a_gt_b(b, a)) {
+ r->in6_u.u6_addr32[3] = 0xffffffff;
+ r->in6_u.u6_addr32[2] = 0xffffffff;
+ r->in6_u.u6_addr32[1] = 0xffffffff;
+ r->in6_u.u6_addr32[0] = 0xffffffff;
+ return r;
+ }
+
+ for (i=3; i>=0; i--) {
+ d = (unsigned long long int)b->in6_u.u6_addr32[i] + c;
+ c = (unsigned long long int)a->in6_u.u6_addr32[i];
+ if (c < d)
+ c += 0x100000000ULL;
+ c -= d;
+ r->in6_u.u6_addr32[i] = c;
+ c >>= 32;
+ }
+
+ return r;
+}
+
+/* a & b -> r */
+static inline struct in6_addr *a_and_b(struct in6_addr *a, struct in6_addr *b, struct in6_addr *r)
+{
+ r->in6_u.u6_addr32[0] = a->in6_u.u6_addr32[0] & b->in6_u.u6_addr32[0];
+ r->in6_u.u6_addr32[1] = a->in6_u.u6_addr32[1] & b->in6_u.u6_addr32[1];
+ r->in6_u.u6_addr32[2] = a->in6_u.u6_addr32[2] & b->in6_u.u6_addr32[2];
+ r->in6_u.u6_addr32[3] = a->in6_u.u6_addr32[3] & b->in6_u.u6_addr32[3];
+ return r;
+}
+
+/* a != 0 */
+int is_set(struct in6_addr *a)
+{
+ return a->in6_u.u6_addr32[0] ||
+ a->in6_u.u6_addr32[1] ||
+ a->in6_u.u6_addr32[2] ||
+ a->in6_u.u6_addr32[3];
+}
+
+/* 1 */
+static struct in6_addr one = { .in6_u.u6_addr32 = {0, 0, 0, 1} };
+
+/* print all networks present between address <low> and address <high> in
+ * cidr format, followed by <eol>.
+ */
+static void convert_range(struct in6_addr *low, struct in6_addr *high, const char *eol, const char *pfx)
+{
+ int bit;
+ struct in6_addr r0;
+ struct in6_addr r1;
+
+ if (a_eq_b(low, high)) {
+ /* single value */
+ printf("%s%s%s%s\n", pfx?pfx:"", pfx?" ":"", get_ipv6_addr(low), eol);
+ return;
+ }
+ else if (a_gt_b(low, high)) {
+ struct in6_addr *swap = low;
+ low = high;
+ high = swap;
+ }
+
+ if (a_eq_b(low, a_plus_b(high, &one, &r0))) {
+ /* full range */
+ printf("%s%s::/0%s\n", pfx?pfx:"", pfx?" ":"", eol);
+ return;
+ }
+ //printf("low=%08x high=%08x\n", low, high);
+
+ bit = 0;
+ while (bit < 128 && a_le_b(a_plus_b(low, hmask(bit, &r0), &r0), high)) {
+
+ /* enlarge mask */
+ if (is_set(a_and_b(low, one_ls_b(bit, &r0), &r0))) {
+ /* can't aggregate anymore, dump and retry from the same bit */
+ printf("%s%s%s/%d%s\n", pfx?pfx:"", pfx?" ":"", get_ipv6_addr(low), 128-bit, eol);
+ a_plus_b(low, one_ls_b(bit, &r0), low);
+ }
+ else {
+ /* try to enlarge the mask as much as possible first */
+ bit++;
+ //printf(" ++bit=%d\n", bit);
+ }
+ }
+ //printf("stopped 1 at low=%08x, bit=%d\n", low, bit);
+
+ bit = 127;
+ while (bit >= 0 && is_set(a_plus_b(a_minus_b(high, low, &r0), &one, &r0))) {
+
+ /* shrink mask */
+ if (is_set(a_and_b(a_plus_b(a_minus_b(high, low, &r0), &one, &r0), one_ls_b(bit, &r1), &r1))) {
+ /* large bit accepted, dump and go on from the same bit */
+ //printf("max: %08x/%d\n", low, 32-bit);
+ printf("%s%s%s/%d%s\n", pfx?pfx:"", pfx?" ":"", get_ipv6_addr(low), 128-bit, eol);
+ a_plus_b(low, one_ls_b(bit, &r0), low);
+ }
+ else {
+ bit--;
+ //printf(" --bit=%d, low=%08x\n", bit, low);
+ }
+ }
+ //printf("stopped at low=%08x\n", low);
+}
+
+static void usage(const char *argv0)
+{
+ fprintf(stderr,
+ "Usage: %s [<addr> ...] < iplist.csv\n"
+ "\n"
+ "This program reads lines starting by two IP addresses and outputs them with\n"
+ "the two IP addresses replaced by a netmask covering the range between these\n"
+ "IPs (inclusive). When multiple ranges are needed, as many lines are emitted.\n"
+ "The IP addresses may be delimited by spaces, tabs or commas. Quotes are\n"
+ "stripped, and lines beginning with a sharp character ('#') are ignored. The\n"
+ "IP addresses may be either in the dotted format or represented as a 32-bit\n"
+ "integer value in network byte order.\n"
+ "\n"
+ "For each optional <addr> specified, only the network it belongs to is returned,\n"
+ "prefixed with the <addr> value.\n"
+ "\n", argv0);
+}
+
+main(int argc, char **argv)
+{
+ char line[MAXLINE];
+ int l, lnum;
+ char *lb, *le, *hb, *he, *err;
+ struct in6_addr sa, da, ta;
+
+ if (argc > 1 && *argv[1] == '-') {
+ usage(argv[0]);
+ exit(1);
+ }
+
+ lnum = 0;
+ while (fgets(line, sizeof(line), stdin) != NULL) {
+ l = strlen(line);
+ if (l && line[l - 1] == '\n')
+ line[--l] = '\0';
+
+ lnum++;
+ /* look for the first field which must be the low address of a range,
+ * in dotted IPv4 format or as an integer. spaces and commas are
+ * considered as delimiters, quotes are removed.
+ */
+ for (lb = line; *lb == ' ' || *lb == '\t' || *lb == ',' || *lb == '"'; lb++);
+ if (!*lb || *lb == '#')
+ continue;
+ for (le = lb + 1; *le != ' ' && *le != '\t' && *le != ',' && *le != '"' && *le; le++);
+ if (!*le)
+ continue;
+ /* we have the low address between lb(included) and le(excluded) */
+ *(le++) = 0;
+
+ for (hb = le; *hb == ' ' || *hb == '\t' || *hb == ',' || *hb == '"'; hb++);
+ if (!*hb || *hb == '#')
+ continue;
+ for (he = hb + 1; *he != ' ' && *he != '\t' && *he != ',' && *he != '"' && *he; he++);
+ if (!*he)
+ continue;
+ /* we have the high address between hb(included) and he(excluded) */
+ *(he++) = 0;
+
+ /* we want to remove a possible ending quote and a possible comma,
+ * not more.
+ */
+ while (*he == '"')
+ *(he++) = ' ';
+ while (*he == ',' || *he == ' ' || *he == '\t')
+ *(he++) = ' ';
+
+ /* if the trailing string is not empty, prefix it with a space */
+ if (*(he-1) == ' ')
+ he--;
+
+ if (inet_pton(AF_INET6, lb, &sa) <= 0) {
+ fprintf(stderr, "Failed to parse source address <%s> at line %d, skipping line\n", lb, lnum);
+ continue;
+ }
+
+ if (inet_pton(AF_INET6, hb, &da) <= 0) {
+ fprintf(stderr, "Failed to parse destination address <%s> at line %d, skipping line\n", hb, lnum);
+ continue;
+ }
+
+ in6_bswap(&sa);
+ in6_bswap(&da);
+
+ if (argc > 1) {
+ for (l = 1; l < argc; l++) {
+ if (inet_pton(AF_INET6, argv[l], &da) <= 0)
+ continue;
+ in6_bswap(&ta);
+ if ((a_le_b(&sa, &ta) && a_le_b(&ta, &da)) || (a_le_b(&da, &ta) && a_le_b(&ta, &sa)))
+ convert_range(&sa, &da, he, argv[l]);
+ }
+ }
+ else {
+ convert_range(&sa, &da, he, NULL);
+ }
+ }
+}