network: Support parsing IPv4 addresses and map them to IPv6

Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>

diff --git a/src/network.c b/src/network.c
index 9d6819cfe450382f4ad6447800b9172d785ef078..11b68dd18291376ceb64964a904299aee956a316 100644 (file)
--- a/src/network.c
+++ b/src/network.c
@@ -78,6 +78,44 @@ LOC_EXPORT int loc_network_new(struct loc_ctx* ctx, struct loc_network** network
        return 0;
 }
 
+static int loc_network_address_family(struct loc_network* network) {
+       if (IN6_IS_ADDR_V4MAPPED(&network->start_address))
+               return AF_INET;
+
+       return AF_INET6;
+}
+
+static int parse_address(struct loc_ctx* ctx, const char* string, struct in6_addr* address) {
+       DEBUG(ctx, "Paring IP address %s\n", string);
+
+       // Try parsing this as an IPv6 address
+       int r = inet_pton(AF_INET6, string, address);
+
+       // If inet_pton returns one it has been successful
+       if (r == 1) {
+               DEBUG(ctx, "%s is an IPv6 address\n", string);
+               return 0;
+       }
+
+       // Try parsing this as an IPv4 address
+       struct in_addr ipv4_address;
+       r = inet_pton(AF_INET, string, &ipv4_address);
+       if (r == 1) {
+               DEBUG(ctx, "%s is an IPv4 address\n", string);
+
+               // Convert to IPv6-mapped address
+               address->s6_addr32[0] = htonl(0x0000);
+               address->s6_addr32[1] = htonl(0x0000);
+               address->s6_addr32[2] = htonl(0xffff);
+               address->s6_addr32[3] = ipv4_address.s_addr;
+
+               return 0;
+       }
+
+       DEBUG(ctx, "%s is not an valid IP address\n", string);
+       return 1;
+}
+
 LOC_EXPORT int loc_network_new_from_string(struct loc_ctx* ctx, struct loc_network** network,
                const char* address_string) {
        struct in6_addr start_address;
@@ -94,12 +132,12 @@ LOC_EXPORT int loc_network_new_from_string(struct loc_ctx* ctx, struct loc_netwo
        unsigned int prefix = strtol(prefix_string, NULL, 10);
 
        // Parse the address
-       int r = inet_pton(AF_INET6, address_string, &start_address);
+       int r = parse_address(ctx, address_string, &start_address);
 
        // Free temporary buffer
        free(buffer);
 
-       if (r == 1) {
+       if (r == 0) {
                r = loc_network_new(ctx, network, start_address, prefix);
        }
 
@@ -127,18 +165,52 @@ LOC_EXPORT struct loc_network* loc_network_unref(struct loc_network* network) {
        return NULL;
 }
 
+static int format_ipv6_address(struct loc_network* network, char* string, size_t length) {
+       const char* ret = inet_ntop(AF_INET6, &network->start_address, string, length);
+       if (!ret)
+               return -1;
+
+       return 0;
+}
+
+static int format_ipv4_address(struct loc_network* network, char* string, size_t length) {
+       struct in_addr ipv4_address;
+       ipv4_address.s_addr = network->start_address.s6_addr32[3];
+
+       const char* ret = inet_ntop(AF_INET, &ipv4_address, string, length);
+       if (!ret)
+               return -1;
+
+       return 0;
+}
+
 LOC_EXPORT char* loc_network_str(struct loc_network* network) {
-       const size_t l = INET6_ADDRSTRLEN + 3;
+       int r;
+       const size_t length = INET6_ADDRSTRLEN + 4;
 
-       char* string = malloc(l);
+       char* string = malloc(length);
        if (!string)
                return NULL;
 
-       const char* ret = inet_ntop(AF_INET6, &network->start_address, string, l);
-       if (!ret) {
-               ERROR(network->ctx, "Could not convert network to string: %s\n", strerror(errno));
+       int family = loc_network_address_family(network);
+       switch (family) {
+               case AF_INET6:
+                       r = format_ipv6_address(network, string, length);
+                       break;
+
+               case AF_INET:
+                       r = format_ipv4_address(network, string, length);
+                       break;
 
+               default:
+                       r = -1;
+                       break;
+       }
+
+       if (r) {
+               ERROR(network->ctx, "Could not convert network to string: %s\n", strerror(errno));
                free(string);
+
                return NULL;
        }