| /* |
| * 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->s6_addr32[0] = ntohl(a->s6_addr32[0]); |
| a->s6_addr32[1] = ntohl(a->s6_addr32[1]); |
| a->s6_addr32[2] = ntohl(a->s6_addr32[2]); |
| a->s6_addr32[3] = ntohl(a->s6_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->s6_addr32[0], |
| addr->s6_addr32[1], |
| addr->s6_addr32[2], |
| addr->s6_addr32[3]); |
| return out; |
| } |
| |
| /* a <= b */ |
| static inline int a_le_b(struct in6_addr *a, struct in6_addr *b) |
| { |
| if (a->s6_addr32[0] < b->s6_addr32[0]) return 1; |
| if (a->s6_addr32[0] > b->s6_addr32[0]) return 0; |
| if (a->s6_addr32[1] < b->s6_addr32[1]) return 1; |
| if (a->s6_addr32[1] > b->s6_addr32[1]) return 0; |
| if (a->s6_addr32[2] < b->s6_addr32[2]) return 1; |
| if (a->s6_addr32[2] > b->s6_addr32[2]) return 0; |
| if (a->s6_addr32[3] < b->s6_addr32[3]) return 1; |
| if (a->s6_addr32[3] > b->s6_addr32[3]) return 0; |
| return 1; |
| } |
| |
| /* a == b */ |
| static inline int a_eq_b(struct in6_addr *a, struct in6_addr *b) |
| { |
| if (a->s6_addr32[0] != b->s6_addr32[0]) return 0; |
| if (a->s6_addr32[1] != b->s6_addr32[1]) return 0; |
| if (a->s6_addr32[2] != b->s6_addr32[2]) return 0; |
| if (a->s6_addr32[3] != b->s6_addr32[3]) return 0; |
| return 1; |
| } |
| |
| /* a > b */ |
| static inline int a_gt_b(struct in6_addr *a, struct in6_addr *b) |
| { |
| if (a->s6_addr32[0] > b->s6_addr32[0]) return 1; |
| if (a->s6_addr32[0] < b->s6_addr32[0]) return 0; |
| if (a->s6_addr32[1] > b->s6_addr32[1]) return 1; |
| if (a->s6_addr32[1] < b->s6_addr32[1]) return 0; |
| if (a->s6_addr32[2] > b->s6_addr32[2]) return 1; |
| if (a->s6_addr32[2] < b->s6_addr32[2]) return 0; |
| if (a->s6_addr32[3] > b->s6_addr32[3]) return 1; |
| if (a->s6_addr32[3] < b->s6_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->s6_addr32[3] = (1 << b) - 1; |
| r->s6_addr32[2] = 0; |
| r->s6_addr32[1] = 0; |
| r->s6_addr32[0] = 0; |
| } |
| else if (b < 64) { |
| r->s6_addr32[3] = 0xffffffff; |
| r->s6_addr32[2] = (1 << (b - 32)) - 1; |
| r->s6_addr32[1] = 0; |
| r->s6_addr32[0] = 0; |
| } |
| else if (b < 96) { |
| r->s6_addr32[3] = 0xffffffff; |
| r->s6_addr32[2] = 0xffffffff; |
| r->s6_addr32[1] = (1 << (b - 64)) - 1; |
| r->s6_addr32[0] = 0; |
| } |
| else if (b < 128) { |
| r->s6_addr32[3] = 0xffffffff; |
| r->s6_addr32[2] = 0xffffffff; |
| r->s6_addr32[1] = 0xffffffff; |
| r->s6_addr32[0] = (1 << (b - 96)) - 1; |
| } |
| else { |
| r->s6_addr32[3] = 0xffffffff; |
| r->s6_addr32[2] = 0xffffffff; |
| r->s6_addr32[1] = 0xffffffff; |
| r->s6_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->s6_addr32[3] = 1 << b; |
| r->s6_addr32[2] = 0; |
| r->s6_addr32[1] = 0; |
| r->s6_addr32[0] = 0; |
| } |
| else if (b < 64) { |
| r->s6_addr32[3] = 0; |
| r->s6_addr32[2] = 1 << (b - 32); |
| r->s6_addr32[1] = 0; |
| r->s6_addr32[0] = 0; |
| } |
| else if (b < 96) { |
| r->s6_addr32[3] = 0; |
| r->s6_addr32[2] = 0; |
| r->s6_addr32[1] = 1 << (b - 64); |
| r->s6_addr32[0] = 0; |
| } |
| else if (b < 128) { |
| r->s6_addr32[3] = 0; |
| r->s6_addr32[2] = 0; |
| r->s6_addr32[1] = 0; |
| r->s6_addr32[0] = 1 << (b - 96); |
| } |
| else { |
| r->s6_addr32[3] = 0; |
| r->s6_addr32[2] = 0; |
| r->s6_addr32[1] = 0; |
| r->s6_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->s6_addr32[i] + |
| (unsigned long long int)b->s6_addr32[i] + c; |
| r->s6_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->s6_addr32[3] = 0xffffffff; |
| r->s6_addr32[2] = 0xffffffff; |
| r->s6_addr32[1] = 0xffffffff; |
| r->s6_addr32[0] = 0xffffffff; |
| return r; |
| } |
| |
| for (i=3; i>=0; i--) { |
| d = (unsigned long long int)b->s6_addr32[i] + c; |
| c = (unsigned long long int)a->s6_addr32[i]; |
| if (c < d) |
| c += 0x100000000ULL; |
| c -= d; |
| r->s6_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->s6_addr32[0] = a->s6_addr32[0] & b->s6_addr32[0]; |
| r->s6_addr32[1] = a->s6_addr32[1] & b->s6_addr32[1]; |
| r->s6_addr32[2] = a->s6_addr32[2] & b->s6_addr32[2]; |
| r->s6_addr32[3] = a->s6_addr32[3] & b->s6_addr32[3]; |
| return r; |
| } |
| |
| /* a != 0 */ |
| int is_set(struct in6_addr *a) |
| { |
| return a->s6_addr32[0] || |
| a->s6_addr32[1] || |
| a->s6_addr32[2] || |
| a->s6_addr32[3]; |
| } |
| |
| /* 1 */ |
| static struct in6_addr one = { .s6_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); |
| } |
| |
| int 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); |
| } |
| } |
| return 0; |
| } |