/*
subnet_parse.c -- handle subnet parsing
- Copyright (C) 2000-2012 Guus Sliepen <guus@tinc-vpn.org>,
+ Copyright (C) 2000-2021 Guus Sliepen <guus@tinc-vpn.org>,
2000-2005 Ivo Timmermans
This program is free software; you can redistribute it and/or modify
for(m = masklen, i = 0; m >= 8; m -= 8, i++) {
result = a[i] - b[i];
- if(result)
+
+ if(result) {
return result;
+ }
}
if(m)
return (a[i] & (0x100 - (1 << (8 - m)))) -
- (b[i] & (0x100 - (1 << (8 - m))));
+ (b[i] & (0x100 - (1 << (8 - m))));
return 0;
}
i = masklen / 8;
masklen %= 8;
- if(masklen)
+ if(masklen) {
a[i++] &= (0x100 - (1 << (8 - masklen)));
+ }
- for(; i < len; i++)
+ for(; i < len; i++) {
a[i] = 0;
+ }
}
void maskcpy(void *va, const void *vb, int masklen, int len) {
char *a = va;
const char *b = vb;
- for(m = masklen, i = 0; m >= 8; m -= 8, i++)
+ 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++)
+ for(; i < len; i++) {
a[i] = 0;
+ }
+}
+
+bool subnetcheck(const subnet_t subnet) {
+ if(((subnet.type == SUBNET_IPV4)
+ && !maskcheck(&subnet.net.ipv4.address, subnet.net.ipv4.prefixlength, sizeof(subnet.net.ipv4.address)))
+ || ((subnet.type == SUBNET_IPV6)
+ && !maskcheck(&subnet.net.ipv6.address, subnet.net.ipv6.prefixlength, sizeof(subnet.net.ipv6.address)))) {
+ return false;
+ }
+
+ return true;
}
bool maskcheck(const void *va, int masklen, int len) {
i = masklen / 8;
masklen %= 8;
- if(masklen && a[i++] & (0xff >> masklen))
+ if(masklen && a[i++] & (0xff >> masklen)) {
return false;
+ }
for(; i < len; i++)
- if(a[i] != 0)
+ if(a[i] != 0) {
return false;
+ }
return true;
}
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);
+ result = memcmp(&a->net.mac.address, &b->net.mac.address, sizeof(a->net.mac.address));
- if(result)
+ if(result) {
return result;
+ }
result = a->weight - b->weight;
- if(result || !a->owner || !b->owner)
+ if(result || !a->owner || !b->owner) {
return result;
+ }
return strcmp(a->owner->name, b->owner->name);
}
result = b->net.ipv4.prefixlength - a->net.ipv4.prefixlength;
- if(result)
+ if(result) {
return result;
+ }
result = memcmp(&a->net.ipv4.address, &b->net.ipv4.address, sizeof(ipv4_t));
- if(result)
+ if(result) {
return result;
+ }
result = a->weight - b->weight;
- if(result || !a->owner || !b->owner)
+ if(result || !a->owner || !b->owner) {
return result;
+ }
return strcmp(a->owner->name, b->owner->name);
}
result = b->net.ipv6.prefixlength - a->net.ipv6.prefixlength;
- if(result)
+ if(result) {
return result;
+ }
result = memcmp(&a->net.ipv6.address, &b->net.ipv6.address, sizeof(ipv6_t));
- if(result)
+ if(result) {
return result;
+ }
result = a->weight - b->weight;
- if(result || !a->owner || !b->owner)
+ if(result || !a->owner || !b->owner) {
return result;
+ }
return strcmp(a->owner->name, b->owner->name);
}
result = a->type - b->type;
- if(result)
+ if(result) {
return result;
+ }
- switch (a->type) {
+ 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);
bool str2net(subnet_t *subnet, const char *subnetstr) {
char str[1024];
strncpy(str, subnetstr, sizeof(str));
+ str[sizeof(str) - 1] = 0;
int consumed;
int weight = DEFAULT_WEIGHT;
char *weight_separator = strchr(str, '#');
- if (weight_separator) {
+
+ if(weight_separator) {
char *weight_str = weight_separator + 1;
- if (sscanf(weight_str, "%d%n", &weight, &consumed) < 1)
+
+ if(sscanf(weight_str, "%d%n", &weight, &consumed) < 1) {
return false;
- if (weight_str[consumed])
+ }
+
+ if(weight_str[consumed]) {
return false;
+ }
+
*weight_separator = 0;
}
int prefixlength = -1;
char *prefixlength_separator = strchr(str, '/');
- if (prefixlength_separator) {
- char* prefixlength_str = prefixlength_separator + 1;
- if (sscanf(prefixlength_str, "%d%n", &prefixlength, &consumed) < 1)
+
+ if(prefixlength_separator) {
+ char *prefixlength_str = prefixlength_separator + 1;
+
+ if(sscanf(prefixlength_str, "%d%n", &prefixlength, &consumed) < 1) {
return false;
- if (prefixlength_str[consumed])
+ }
+
+ if(prefixlength_str[consumed]) {
return false;
+ }
+
*prefixlength_separator = 0;
- if (prefixlength < 0)
+ if(prefixlength < 0) {
return false;
+ }
}
uint16_t x[8];
- if (sscanf(str, "%hx:%hx:%hx:%hx:%hx:%hx%n", &x[0], &x[1], &x[2], &x[3], &x[4], &x[5], &consumed) >= 6 && !str[consumed]) {
+
+ if(sscanf(str, "%hx:%hx:%hx:%hx:%hx:%hx%n", &x[0], &x[1], &x[2], &x[3], &x[4], &x[5], &consumed) >= 6 && !str[consumed]) {
/*
Normally we should check that each part has two digits to prevent ambiguities.
- However, in old tinc versions net2str() will agressively return MAC addresses with one-digit parts,
+ However, in old tinc versions net2str() will aggressively return MAC addresses with one-digit parts,
so we have to accept them otherwise we would be unable to parse ADD_SUBNET messages.
*/
- if (prefixlength >= 0)
+ if(prefixlength >= 0) {
return false;
+ }
subnet->type = SUBNET_MAC;
subnet->weight = weight;
- for(int i = 0; i < 6; i++)
+
+ for(int i = 0; i < 6; i++) {
subnet->net.mac.address.x[i] = x[i];
+ }
+
return true;
}
- if (sscanf(str, "%hu.%hu.%hu.%hu%n", &x[0], &x[1], &x[2], &x[3], &consumed) >= 4 && !str[consumed]) {
- if (prefixlength == -1)
+ if(sscanf(str, "%hu.%hu.%hu.%hu%n", &x[0], &x[1], &x[2], &x[3], &consumed) >= 4 && !str[consumed]) {
+ if(prefixlength == -1) {
prefixlength = 32;
- if (prefixlength > 32)
+ }
+
+ if(prefixlength > 32) {
return false;
+ }
subnet->type = SUBNET_IPV4;
subnet->net.ipv4.prefixlength = prefixlength;
subnet->weight = weight;
+
for(int i = 0; i < 4; i++) {
- if (x[i] > 255)
+ if(x[i] > 255) {
return false;
+ }
+
subnet->net.ipv4.address.x[i] = x[i];
}
+
return true;
}
/* IPv6 */
- char* last_colon = strrchr(str, ':');
- if (last_colon && sscanf(last_colon, ":%hu.%hu.%hu.%hu%n", &x[0], &x[1], &x[2], &x[3], &consumed) >= 4 && !last_colon[consumed]) {
+ char *last_colon = strrchr(str, ':');
+
+ if(last_colon && sscanf(last_colon, ":%hu.%hu.%hu.%hu%n", &x[0], &x[1], &x[2], &x[3], &consumed) >= 4 && !last_colon[consumed]) {
/* Dotted quad suffix notation, convert to standard IPv6 notation */
- for (int i = 0; i < 4; i++)
- if (x[i] > 255)
+ for(int i = 0; i < 4; i++)
+ if(x[i] > 255) {
return false;
- sprintf(last_colon, ":%02hx%02hx:%02hx%02hx", x[0], x[1], x[2], x[3]);
+ }
+
+ snprintf(last_colon, sizeof(str) - (last_colon - str), ":%02x%02x:%02x%02x", x[0], x[1], x[2], x[3]);
}
- char* double_colon = strstr(str, "::");
- if (double_colon) {
+ char *double_colon = strstr(str, "::");
+
+ if(double_colon) {
/* Figure out how many zero groups we need to expand */
int zero_group_count = 8;
- for (const char* cur = str; *cur; *cur && cur++)
- if (*cur != ':') {
+
+ for(const char *cur = str; *cur; cur++)
+ if(*cur != ':') {
zero_group_count--;
- for (; *cur && *cur != ':'; cur++);
+
+ while(cur[1] && cur[1] != ':') {
+ cur++;
+ }
}
- if (zero_group_count < 1)
+
+ if(zero_group_count < 1) {
return false;
+ }
/* Split the double colon in the middle to make room for zero groups */
double_colon++;
memmove(double_colon + (zero_group_count * 2 - 1), double_colon, strlen(double_colon) + 1);
/* Write zero groups in the resulting gap, overwriting the second colon */
- for (int i = 0; i < zero_group_count; i++)
+ for(int i = 0; i < zero_group_count; i++) {
memcpy(&double_colon[i * 2], "0:", 2);
+ }
/* Remove any leading or trailing colons */
- if (str[0] == ':')
+ if(str[0] == ':') {
memmove(&str[0], &str[1], strlen(&str[1]) + 1);
- if (str[strlen(str) - 1] == ':')
+ }
+
+ if(str[strlen(str) - 1] == ':') {
str[strlen(str) - 1] = 0;
+ }
}
- if (sscanf(str, "%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx%n",
- &x[0], &x[1], &x[2], &x[3], &x[4], &x[5], &x[6], &x[7], &consumed) >= 8 && !str[consumed]) {
- if (prefixlength == -1)
+ if(sscanf(str, "%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx%n",
+ &x[0], &x[1], &x[2], &x[3], &x[4], &x[5], &x[6], &x[7], &consumed) >= 8 && !str[consumed]) {
+ if(prefixlength == -1) {
prefixlength = 128;
- if (prefixlength > 128)
+ }
+
+ if(prefixlength > 128) {
return false;
+ }
subnet->type = SUBNET_IPV6;
subnet->net.ipv6.prefixlength = prefixlength;
subnet->weight = weight;
- for(int i = 0; i < 8; i++)
+
+ for(int i = 0; i < 8; i++) {
subnet->net.ipv6.address.x[i] = htons(x[i]);
+ }
+
return true;
}
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);
+ logger(DEBUG_ALWAYS, LOG_ERR, "net2str() was called with netstr=%p, subnet=%p!", (void *)netstr, (void *)subnet);
return false;
}
int result;
int prefixlength = -1;
- switch (subnet->type) {
- case SUBNET_MAC:
- result = snprintf(netstr, len, "%02hx:%02hx:%02hx:%02hx:%02hx:%02hx",
- 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:
- result = snprintf(netstr, len, "%hu.%hu.%hu.%hu",
- subnet->net.ipv4.address.x[0],
- subnet->net.ipv4.address.x[1],
- subnet->net.ipv4.address.x[2],
- subnet->net.ipv4.address.x[3]);
- prefixlength = subnet->net.ipv4.prefixlength;
- if (prefixlength == 32)
- prefixlength = -1;
- break;
-
- case SUBNET_IPV6:
- result = snprintf(netstr, len, "%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx",
- 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]));
- prefixlength = subnet->net.ipv6.prefixlength;
- if (prefixlength == 128)
- prefixlength = -1;
- break;
-
- default:
- logger(DEBUG_ALWAYS, LOG_ERR, "net2str() was called with unknown subnet type %d, exiting!", subnet->type);
- exit(1);
+
+ switch(subnet->type) {
+ case SUBNET_MAC:
+ result = snprintf(netstr, len, "%02x:%02x:%02x:%02x:%02x:%02x",
+ 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]);
+ netstr += result;
+ len -= result;
+ break;
+
+ case SUBNET_IPV4:
+ result = snprintf(netstr, len, "%u.%u.%u.%u",
+ subnet->net.ipv4.address.x[0],
+ subnet->net.ipv4.address.x[1],
+ subnet->net.ipv4.address.x[2],
+ subnet->net.ipv4.address.x[3]);
+ netstr += result;
+ len -= result;
+ prefixlength = subnet->net.ipv4.prefixlength;
+
+ if(prefixlength == 32) {
+ prefixlength = -1;
+ }
+
+ break;
+
+ case SUBNET_IPV6: {
+ /* Find the longest sequence of consecutive zeroes */
+ int max_zero_length = 0;
+ int max_zero_length_index = 0;
+ int current_zero_length = 0;
+ int current_zero_length_index = 0;
+
+ for(int i = 0; i < 8; i++) {
+ if(subnet->net.ipv6.address.x[i] != 0) {
+ current_zero_length = 0;
+ } else {
+ if(current_zero_length == 0) {
+ current_zero_length_index = i;
+ }
+
+ current_zero_length++;
+
+ if(current_zero_length > max_zero_length) {
+ max_zero_length = current_zero_length;
+ max_zero_length_index = current_zero_length_index;
+ }
+ }
+ }
+
+ /* Print the address */
+ for(int i = 0; i < 8;) {
+ if(max_zero_length > 1 && max_zero_length_index == i) {
+ /* Shorten the representation as per RFC 5952 */
+ const char *const FORMATS[] = { "%.1s", "%.2s", "%.3s" };
+ const char *const *format = &FORMATS[0];
+
+ if(i == 0) {
+ format++;
+ }
+
+ if(i + max_zero_length == 8) {
+ format++;
+ }
+
+ result = snprintf(netstr, len, *format, ":::");
+ i += max_zero_length;
+ } else {
+ result = snprintf(netstr, len, "%x:", ntohs(subnet->net.ipv6.address.x[i]));
+ i++;
+ }
+
+ netstr += result;
+ len -= result;
+ }
+
+ /* Remove the trailing colon */
+ netstr--;
+ len++;
+ *netstr = 0;
+
+ prefixlength = subnet->net.ipv6.prefixlength;
+
+ if(prefixlength == 128) {
+ prefixlength = -1;
+ }
+
+ break;
}
- netstr += result;
- len -= result;
- if (prefixlength >= 0) {
+ default:
+ logger(DEBUG_ALWAYS, LOG_ERR, "net2str() was called with unknown subnet type %d, exiting!", subnet->type);
+ exit(1);
+ }
+
+ if(prefixlength >= 0) {
result = snprintf(netstr, len, "/%d", prefixlength);
netstr += result;
len -= result;
}
- if (subnet->weight != DEFAULT_WEIGHT) {
+ if(subnet->weight != DEFAULT_WEIGHT) {
snprintf(netstr, len, "#%d", subnet->weight);
- netstr += result;
- len -= result;
}
return true;