X-Git-Url: https://tinc-vpn.org/git/browse?a=blobdiff_plain;f=src%2Fsubnet_parse.c;h=d5b84eb647f6fa710e4f3eeb9ab2ced28ded7ae2;hb=refs%2Fheads%2F1.1;hp=c919b59a8eef028710498f77052ebb894c6ba350;hpb=04fc19112da5e7fcefefcf6e490987cdcfb6f620;p=tinc

diff --git a/src/subnet_parse.c b/src/subnet_parse.c
index c919b59a..e9271c12 100644
--- a/src/subnet_parse.c
+++ b/src/subnet_parse.c
@@ -1,6 +1,6 @@
 /*
     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
@@ -22,78 +22,94 @@
 
 #include "logger.h"
 #include "net.h"
-#include "netutl.h"
 #include "subnet.h"
-#include "utils.h"
-#include "xalloc.h"
 
 /* Changing this default will affect ADD_SUBNET messages - beware of inconsistencies between versions */
 static const int DEFAULT_WEIGHT = 10;
 
 /* 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;
+int maskcmp(const void *va, const void *vb, size_t masklen) {
+	size_t i, m;
+	const uint8_t *a = va;
+	const uint8_t *b = vb;
 
 	for(m = masklen, i = 0; m >= 8; m -= 8, i++) {
-		result = a[i] - b[i];
-		if(result)
+		int result = a[i] - b[i];
+
+		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;
 }
 
-void mask(void *va, int masklen, int len) {
-	int i;
-	char *a = va;
+void mask(void *va, size_t masklen, size_t len) {
+	size_t i;
+	uint8_t *a = va;
 
 	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) {
-	int i, m;
-	char *a = va;
-	const char *b = vb;
+void maskcpy(void *va, const void *vb, size_t masklen, size_t len) {
+	size_t i, m;
+	uint8_t *a = va;
+	const uint8_t *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 maskcheck(const void *va, int masklen, int len) {
-	int i;
-	const char *a = va;
+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, size_t masklen, size_t len) {
+	size_t i;
+	const uint8_t *a = va;
 
 	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;
 }
@@ -103,15 +119,17 @@ bool maskcheck(const void *va, int masklen, int len) {
 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);
 }
@@ -121,18 +139,21 @@ static int subnet_compare_ipv4(const subnet_t *a, const subnet_t *b) {
 
 	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);
 }
@@ -142,37 +163,42 @@ static int subnet_compare_ipv6(const subnet_t *a, const subnet_t *b) {
 
 	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);
 }
 
 int subnet_compare(const subnet_t *a, const subnet_t *b) {
-	int result;
-
-	result = a->type - b->type;
+	int result = (int)a->type - (int)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);
@@ -184,227 +210,164 @@ int subnet_compare(const subnet_t *a, const subnet_t *b) {
 /* Ascii representation of subnets */
 
 bool str2net(subnet_t *subnet, const char *subnetstr) {
-	char str[1024];
+	char str[64];
 	strncpy(str, subnetstr, sizeof(str));
-	str[sizeof str - 1] = 0;
+	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(inet_pton(AF_INET, str, &subnet->net.ipv4.address)) {
+		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)
-				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]) {
-		/* Dotted quad suffix notation, convert to standard IPv6 notation */
-		for (int i = 0; i < 4; i++)
-			if (x[i] > 255)
-				return false;
-		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) {
-		/* Figure out how many zero groups we need to expand */
-		int zero_group_count = 8;
-		for (const char* cur = str; *cur; cur++)
-			if (*cur != ':') {
-				zero_group_count--;
-				while(cur[1] && cur[1] != ':')
-					cur++;
-			}
-		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++)
-			memcpy(&double_colon[i * 2], "0:", 2);
-
-		/* Remove any leading or trailing colons */
-		if (str[0] == ':')
-			memmove(&str[0], &str[1], strlen(&str[1]) + 1);
-		if (str[strlen(str) - 1] == ':')
-			str[strlen(str) - 1] = 0;
+		return true;
 	}
 
-	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(inet_pton(AF_INET6, str, &subnet->net.ipv6.address)) {
+		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++)
-			subnet->net.ipv6.address.x[i] = htons(x[i]);
+
 		return true;
 	}
 
 	return false;
 }
 
-bool net2str(char *netstr, int len, const subnet_t *subnet) {
+bool net2str(char *netstr, size_t 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, "%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, "%hx:", 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;
+
+	switch(subnet->type) {
+	case SUBNET_MAC:
+		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]);
+		break;
+
+	case SUBNET_IPV4:
+		inet_ntop(AF_INET, &subnet->net.ipv4.address, netstr, len);
+		prefixlength = subnet->net.ipv4.prefixlength;
+
+		if(prefixlength == 32) {
+			prefixlength = -1;
+		}
+
+		break;
+
+	case SUBNET_IPV6: {
+		inet_ntop(AF_INET6, &subnet->net.ipv6.address, netstr, len);
+		prefixlength = subnet->net.ipv6.prefixlength;
+
+		if(prefixlength == 128) {
+			prefixlength = -1;
 		}
 
-		default:
-			logger(DEBUG_ALWAYS, LOG_ERR, "net2str() was called with unknown subnet type %d, exiting!", subnet->type);
-			exit(1);
+		break;
+	}
+
+	default:
+		logger(DEBUG_ALWAYS, LOG_ERR, "net2str() was called with unknown subnet type %d, exiting!", subnet->type);
+		exit(1);
 	}
 
-	if (prefixlength >= 0) {
+	size_t used = strlen(netstr);
+	netstr += used;
+	len -= used;
+
+	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;