luci-lib-ip: add functions to deal with IPv6 mapped IPv6

[project/luci.git] / libs / luci-lib-ip / src / ip.c

diff --git a/libs/luci-lib-ip/src/ip.c b/libs/luci-lib-ip/src/ip.c
index 8c9155b..b91966c 100644 (file)
--- a/libs/luci-lib-ip/src/ip.c
+++ b/libs/luci-lib-ip/src/ip.c
@@ -126,27 +126,23 @@ static bool parse_mask(int family, const char *mask, int *bits)
 
 static bool parse_cidr(const char *dest, cidr_t *pp)
 {
-       char *p, *a, buf[INET6_ADDRSTRLEN * 2 + 2];
+       char *p, buf[INET6_ADDRSTRLEN * 2 + 2];
        uint8_t bitlen = 0;
 
        strncpy(buf, dest, sizeof(buf) - 1);
 
-       a = buf;
        p = strchr(buf, '/');
 
        if (p)
                *p++ = 0;
 
-       if (!strncasecmp(buf, "::ffff:", 7))
-               a += 7;
-
-       if (inet_pton(AF_INET, a, &pp->addr.v4))
+       if (inet_pton(AF_INET, buf, &pp->addr.v4))
        {
                bitlen = 32;
                pp->family = AF_INET;
                pp->len = sizeof(struct in_addr);
        }
-       else if (inet_pton(AF_INET6, a, &pp->addr.v6))
+       else if (inet_pton(AF_INET6, buf, &pp->addr.v6))
        {
                bitlen = 128;
                pp->family = AF_INET6;
@@ -299,10 +295,10 @@ static int _cidr_new(lua_State *L, int index, int family, bool mask)
                        cidr.family = AF_INET6;
                        cidr.bits = 128;
                        cidr.len = sizeof(cidr.addr.v6);
-                       cidr.addr.v6.s6_addr[15] = n;
-                       cidr.addr.v6.s6_addr[14] = (n >> 8);
-                       cidr.addr.v6.s6_addr[13] = (n >> 16);
-                       cidr.addr.v6.s6_addr[12] = (n >> 24);
+                       cidr.addr.v6.s6_addr[12] = n;
+                       cidr.addr.v6.s6_addr[13] = (n >> 8);
+                       cidr.addr.v6.s6_addr[14] = (n >> 16);
+                       cidr.addr.v6.s6_addr[15] = (n >> 24);
                }
                else
                {
@@ -383,6 +379,31 @@ static int cidr_is4linklocal(lua_State *L)
        return 1;
 }
 
+static bool _is_mapped4(cidr_t *p)
+{
+       return (p->family == AF_INET6 &&
+               p->addr.v6.s6_addr[0] == 0 &&
+               p->addr.v6.s6_addr[1] == 0 &&
+               p->addr.v6.s6_addr[2] == 0 &&
+               p->addr.v6.s6_addr[3] == 0 &&
+               p->addr.v6.s6_addr[4] == 0 &&
+               p->addr.v6.s6_addr[5] == 0 &&
+               p->addr.v6.s6_addr[6] == 0 &&
+               p->addr.v6.s6_addr[7] == 0 &&
+               p->addr.v6.s6_addr[8] == 0 &&
+               p->addr.v6.s6_addr[9] == 0 &&
+               p->addr.v6.s6_addr[10] == 0xFF &&
+               p->addr.v6.s6_addr[11] == 0xFF);
+}
+
+static int cidr_is6mapped4(lua_State *L)
+{
+       cidr_t *p = L_checkcidr(L, 1, NULL);
+
+       lua_pushboolean(L, _is_mapped4(p));
+       return 1;
+}
+
 static int cidr_is6(lua_State *L)
 {
        cidr_t *p = L_checkcidr(L, 1, NULL);
@@ -550,6 +571,26 @@ static int cidr_broadcast(lua_State *L)
        return 1;
 }
 
+static int cidr_mapped4(lua_State *L)
+{
+       cidr_t *p1 = L_checkcidr(L, 1, NULL);
+       cidr_t *p2;
+
+       if (!_is_mapped4(p1))
+               return 0;
+
+       if (!(p2 = lua_newuserdata(L, sizeof(*p2))))
+               return 0;
+
+       p2->family = AF_INET;
+       p2->bits = (p1->bits > 32) ? 32 : p1->bits;
+       memcpy(&p2->addr.v4, p1->addr.v6.s6_addr + 12, sizeof(p2->addr.v4));
+
+       luaL_getmetatable(L, LUCI_IP_CIDR);
+       lua_setmetatable(L, -2);
+       return 1;
+}
+
 static int cidr_contains(lua_State *L)
 {
        cidr_t *p1 = L_checkcidr(L, 1, NULL);
@@ -586,7 +627,7 @@ static int _cidr_add_sub(lua_State *L, bool add)
        {
                if (p1->family == AF_INET6)
                {
-                       for (i = 0, carry = 0; i < sizeof(r); i++)
+                       for (i = 0, carry = 0; i < sizeof(r.addr.v6.s6_addr); i++)
                        {
                                if (add)
                                {
@@ -1123,7 +1164,7 @@ out:
 
 static int neighbor_dump(lua_State *L)
 {
-       cidr_t p;
+       cidr_t p = { };
        const char *s;
        struct ether_addr *mac;
        struct dump_filter filter = { .type = 0xFF & ~NUD_NOARP };
@@ -1309,6 +1350,7 @@ static const luaL_reg ip_cidr_methods[] = {
        { "is4linklocal",       cidr_is4linklocal },
        { "is6",                        cidr_is6          },
        { "is6linklocal",       cidr_is6linklocal },
+       { "is6mapped4",         cidr_is6mapped4   },
        { "lower",                      cidr_lower        },
        { "higher",                     cidr_higher       },
        { "equal",                      cidr_equal        },
@@ -1317,6 +1359,7 @@ static const luaL_reg ip_cidr_methods[] = {
        { "host",                       cidr_host         },
        { "mask",                       cidr_mask         },
        { "broadcast",          cidr_broadcast    },
+       { "mapped4",            cidr_mapped4      },
        { "contains",       cidr_contains     },
        { "add",                        cidr_add          },
        { "sub",                        cidr_sub          },