/* _gethostaddr
*
* gets the address of a host passed by name, and fills out a sockaddr
* structure
*
* Arguments:
* L lua State
* addr ip address or hostname
* type SOCK_STREAM or SOCK_DGRAM
* port port number for sockaddr
* family (out) address family (AF_INET or AF_INET6) of address
* protocol (out) protocol of address
* sa (out) pointer to struct sockaddr to fill with data.
* slen (inout) length of sa, and on return length of data
*
* Returns:
* 0 when the lookup succeeded, -1 otherwise
* On success, the arguments family, protocol, sa and slen will have
* been updated with values from the looked up address
*/
static int _gethostaddr(lua_State *L, const char *addr, int type, int port, int *family, int *protocol, struct sockaddr *sa, socklen_t *slen)
{
struct addrinfo hint, *info =0;
memset(&hint, 0, sizeof(hint));
hint.ai_family = AF_UNSPEC;
hint.ai_socktype = type;
if (_needsnolookup(addr))
hint.ai_flags = AI_NUMERICHOST;
int err = getaddrinfo(addr, 0, &hint, &info);
if (err != 0) {
if (info) freeaddrinfo(info);
return lsocket_error(L, gai_strerror(err));
} else if (info->ai_family != AF_INET && info->ai_family != AF_INET6) {
if (info) freeaddrinfo(info);
return lsocket_error(L, "unknown address family");
}
*family = info->ai_family;
*slen = info->ai_addrlen;
*protocol = info->ai_protocol;
memcpy(sa, info->ai_addr, *slen);
if (*family == AF_INET)
((struct sockaddr_in*) sa)->sin_port = htons(port);
else
((struct sockaddr_in6*) sa)->sin6_port = htons(port);
freeaddrinfo(info);
return 0;
}
/* ares_aresolver
*
* starts an asynchronous getaddrinfo request
*
* Arguments:
* L Lua State
*
* Lua Stack:
* 1 the name to resolve
*
* Lua Returns:
* +1 true, if the cancel request was sent, nil + error message if an
* error occurred.
*/
static int ares_aresolver(lua_State *L)
{
const char *name = luaL_checkstring(L, 1);
aResolver *ares = ares_pushaResolver(L);
struct addrinfo hint;
memset(&hint, 0, sizeof(hint));
hint.ai_family = AF_UNSPEC;
/* reduce the number of duplicate hits, this makes no difference for
* the actual dns resolving.
*/
hint.ai_protocol = IPPROTO_TCP;
hint.ai_socktype = SOCK_STREAM;
if (_needsnolookup(name))
hint.ai_flags = AI_NUMERICHOST;
ares->rq = gai_start(name, 0, &hint);
if (ares->rq == NULL)
return ares_error(L, strerror(errno));
return 1;
}
/* lsocket_resolve
*
* resolves a name to an address
*
* Arguments:
* L lua State
*
* Lua Stack:
* 1 name of host to resolve
*
* Lua Returns:
* +1 a table of all addresses the argument resolves to. For each address,
* a subtable with the fields family and addr is created.
*/
static int lsocket_resolve(lua_State *L)
{
const char *name = luaL_checkstring(L, 1);
char buf[TOSTRING_BUFSIZ];
struct addrinfo hint, *info =0;
memset(&hint, 0, sizeof(hint));
hint.ai_family = AF_UNSPEC;
if (_needsnolookup(name))
hint.ai_flags = AI_NUMERICHOST;
int err = getaddrinfo(name, 0, &hint, &info);
if (err != 0) {
if (info) freeaddrinfo(info);
return lsocket_error(L, gai_strerror(err));
}
int i = 1;
lua_newtable(L);
while (info) {
if (info->ai_family == AF_INET || info->ai_family == AF_INET6) {
lua_newtable(L);
lua_pushliteral(L, "family");
lua_pushstring(L, info->ai_family == AF_INET ? LSOCKET_INET : LSOCKET_INET6);
lua_rawset(L, -3);
lua_pushliteral(L, "addr");
lua_pushstring(L, _addr2string(info->ai_addr, buf, TOSTRING_BUFSIZ));
lua_rawset(L, -3);
lua_rawseti(L, -2, i++);
info = info->ai_next;
}
/* silently ignore unknown address families */
}
freeaddrinfo(info);
return 1;
}
