X-Git-Url: http://tinc-vpn.org/git/browse?a=blobdiff_plain;f=src%2Fsubnet_parse.c;fp=src%2Fsubnet_parse.c;h=a3c904f5945ae8ca4693e80ff9bff3de30f74ff3;hb=3c7003893fe2f82023d0d4f54b488bb7a16d0007;hp=0000000000000000000000000000000000000000;hpb=e72e6febfeddbd4354560388c8e0e125a8017909;p=tinc diff --git a/src/subnet_parse.c b/src/subnet_parse.c new file mode 100644 index 00000000..a3c904f5 --- /dev/null +++ b/src/subnet_parse.c @@ -0,0 +1,382 @@ +/* + subnet_parse.c -- handle subnet parsing + Copyright (C) 2000-2012 Guus Sliepen , + 2000-2005 Ivo Timmermans + + 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. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License along + with this program; if not, write to the Free Software Foundation, Inc., + 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. +*/ + +#include "system.h" + +#include "logger.h" +#include "net.h" +#include "netutl.h" +#include "subnet.h" +#include "utils.h" +#include "xalloc.h" + +/* Subnet mask handling */ + +int maskcmp(const void *va, const void *vb, int masklen) { + int i, m, result; + const char *a = va; + const char *b = vb; + + for(m = masklen, i = 0; m >= 8; m -= 8, i++) { + result = a[i] - b[i]; + if(result) + return result; + } + + if(m) + return (a[i] & (0x100 - (1 << (8 - m)))) - + (b[i] & (0x100 - (1 << (8 - m)))); + + return 0; +} + +void mask(void *va, int masklen, int len) { + int i; + char *a = va; + + i = masklen / 8; + masklen %= 8; + + if(masklen) + a[i++] &= (0x100 - (1 << (8 - masklen))); + + for(; i < len; i++) + a[i] = 0; +} + +void maskcpy(void *va, const void *vb, int masklen, int len) { + int i, m; + char *a = va; + const char *b = vb; + + for(m = masklen, i = 0; m >= 8; m -= 8, i++) + a[i] = b[i]; + + if(m) { + a[i] = b[i] & (0x100 - (1 << (8 - m))); + i++; + } + + for(; i < len; i++) + a[i] = 0; +} + +bool maskcheck(const void *va, int masklen, int len) { + int i; + const char *a = va; + + i = masklen / 8; + masklen %= 8; + + if(masklen && a[i++] & (0xff >> masklen)) + return false; + + for(; i < len; i++) + if(a[i] != 0) + return false; + + return true; +} + +/* Subnet comparison */ + +static int subnet_compare_mac(const subnet_t *a, const subnet_t *b) { + int result; + + result = memcmp(&a->net.mac.address, &b->net.mac.address, sizeof a->net.mac.address); + + if(result) + return result; + + result = a->weight - b->weight; + + if(result || !a->owner || !b->owner) + return result; + + return strcmp(a->owner->name, b->owner->name); +} + +static int subnet_compare_ipv4(const subnet_t *a, const subnet_t *b) { + int result; + + result = b->net.ipv4.prefixlength - a->net.ipv4.prefixlength; + + if(result) + return result; + + result = memcmp(&a->net.ipv4.address, &b->net.ipv4.address, sizeof(ipv4_t)); + + if(result) + return result; + + result = a->weight - b->weight; + + if(result || !a->owner || !b->owner) + return result; + + return strcmp(a->owner->name, b->owner->name); +} + +static int subnet_compare_ipv6(const subnet_t *a, const subnet_t *b) { + int result; + + result = b->net.ipv6.prefixlength - a->net.ipv6.prefixlength; + + if(result) + return result; + + result = memcmp(&a->net.ipv6.address, &b->net.ipv6.address, sizeof(ipv6_t)); + + if(result) + return result; + + result = a->weight - b->weight; + + if(result || !a->owner || !b->owner) + return result; + + return strcmp(a->owner->name, b->owner->name); +} + +int subnet_compare(const subnet_t *a, const subnet_t *b) { + int result; + + result = a->type - b->type; + + if(result) + return result; + + switch (a->type) { + case SUBNET_MAC: + return subnet_compare_mac(a, b); + case SUBNET_IPV4: + return subnet_compare_ipv4(a, b); + case SUBNET_IPV6: + return subnet_compare_ipv6(a, b); + default: + logger(DEBUG_ALWAYS, LOG_ERR, "subnet_compare() was called with unknown subnet type %d, exitting!", a->type); + exit(1); + } + + return 0; +} + +/* Ascii representation of subnets */ + +bool str2net(subnet_t *subnet, const char *subnetstr) { + int i, l; + uint16_t x[8]; + int weight = 10; + + if(sscanf(subnetstr, "%hu.%hu.%hu.%hu/%d#%d", + &x[0], &x[1], &x[2], &x[3], &l, &weight) >= 5) { + if(l < 0 || l > 32) + return false; + + subnet->type = SUBNET_IPV4; + subnet->net.ipv4.prefixlength = l; + subnet->weight = weight; + + for(i = 0; i < 4; i++) { + if(x[i] > 255) + return false; + subnet->net.ipv4.address.x[i] = x[i]; + } + + return true; + } + + if(sscanf(subnetstr, "%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx/%d#%d", + &x[0], &x[1], &x[2], &x[3], &x[4], &x[5], &x[6], &x[7], + &l, &weight) >= 9) { + if(l < 0 || l > 128) + return false; + + subnet->type = SUBNET_IPV6; + subnet->net.ipv6.prefixlength = l; + subnet->weight = weight; + + for(i = 0; i < 8; i++) + subnet->net.ipv6.address.x[i] = htons(x[i]); + + return true; + } + + if(sscanf(subnetstr, "%hu.%hu.%hu.%hu#%d", &x[0], &x[1], &x[2], &x[3], &weight) >= 4) { + subnet->type = SUBNET_IPV4; + subnet->net.ipv4.prefixlength = 32; + subnet->weight = weight; + + for(i = 0; i < 4; i++) { + if(x[i] > 255) + return false; + subnet->net.ipv4.address.x[i] = x[i]; + } + + return true; + } + + if(sscanf(subnetstr, "%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx#%d", + &x[0], &x[1], &x[2], &x[3], &x[4], &x[5], &x[6], &x[7], &weight) >= 8) { + subnet->type = SUBNET_IPV6; + subnet->net.ipv6.prefixlength = 128; + subnet->weight = weight; + + for(i = 0; i < 8; i++) + subnet->net.ipv6.address.x[i] = htons(x[i]); + + return true; + } + + if(sscanf(subnetstr, "%hx:%hx:%hx:%hx:%hx:%hx#%d", + &x[0], &x[1], &x[2], &x[3], &x[4], &x[5], &weight) >= 6) { + subnet->type = SUBNET_MAC; + subnet->weight = weight; + + for(i = 0; i < 6; i++) + subnet->net.mac.address.x[i] = x[i]; + + return true; + } + + // IPv6 short form + if(strstr(subnetstr, "::")) { + const char *p; + char *q; + int colons = 0; + + // Count number of colons + for(p = subnetstr; *p; p++) + if(*p == ':') + colons++; + + if(colons > 7) + return false; + + // Scan numbers before the double colon + p = subnetstr; + for(i = 0; i < colons; i++) { + if(*p == ':') + break; + x[i] = strtoul(p, &q, 0x10); + if(!q || p == q || *q != ':') + return false; + p = ++q; + } + + p++; + colons -= i; + if(!i) { + p++; + colons--; + } + + if(!*p || *p == '/' || *p == '#') + colons--; + + // Fill in the blanks + for(; i < 8 - colons; i++) + x[i] = 0; + + // Scan the remaining numbers + for(; i < 8; i++) { + x[i] = strtoul(p, &q, 0x10); + if(!q || p == q) + return false; + if(i == 7) { + p = q; + break; + } + if(*q != ':') + return false; + p = ++q; + } + + l = 128; + if(*p == '/') + sscanf(p, "/%d#%d", &l, &weight); + else if(*p == '#') + sscanf(p, "#%d", &weight); + + if(l < 0 || l > 128) + return false; + + subnet->type = SUBNET_IPV6; + subnet->net.ipv6.prefixlength = l; + subnet->weight = weight; + + for(i = 0; i < 8; i++) + subnet->net.ipv6.address.x[i] = htons(x[i]); + + return true; + } + + return false; +} + +bool net2str(char *netstr, int len, const subnet_t *subnet) { + if(!netstr || !subnet) { + logger(DEBUG_ALWAYS, LOG_ERR, "net2str() was called with netstr=%p, subnet=%p!", netstr, subnet); + return false; + } + + switch (subnet->type) { + case SUBNET_MAC: + snprintf(netstr, len, "%hx:%hx:%hx:%hx:%hx:%hx#%d", + subnet->net.mac.address.x[0], + subnet->net.mac.address.x[1], + subnet->net.mac.address.x[2], + subnet->net.mac.address.x[3], + subnet->net.mac.address.x[4], + subnet->net.mac.address.x[5], + subnet->weight); + break; + + case SUBNET_IPV4: + snprintf(netstr, len, "%hu.%hu.%hu.%hu/%d#%d", + subnet->net.ipv4.address.x[0], + subnet->net.ipv4.address.x[1], + subnet->net.ipv4.address.x[2], + subnet->net.ipv4.address.x[3], + subnet->net.ipv4.prefixlength, + subnet->weight); + break; + + case SUBNET_IPV6: + snprintf(netstr, len, "%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx/%d#%d", + ntohs(subnet->net.ipv6.address.x[0]), + ntohs(subnet->net.ipv6.address.x[1]), + ntohs(subnet->net.ipv6.address.x[2]), + ntohs(subnet->net.ipv6.address.x[3]), + ntohs(subnet->net.ipv6.address.x[4]), + ntohs(subnet->net.ipv6.address.x[5]), + ntohs(subnet->net.ipv6.address.x[6]), + ntohs(subnet->net.ipv6.address.x[7]), + subnet->net.ipv6.prefixlength, + subnet->weight); + break; + + default: + logger(DEBUG_ALWAYS, LOG_ERR, "net2str() was called with unknown subnet type %d, exiting!", subnet->type); + exit(1); + } + + return true; +}