/**
* Translates the name of a service location (for example, a host name) and/or
* a service name and returns a set of socket addresses and associated
* information to be used in creating a socket with which to address the
* specified service.
* Memory for the result is allocated internally and must be freed by calling
* lwip_freeaddrinfo()!
*
* Due to a limitation in dns_gethostbyname, only the first address of a
* host is returned.
* Also, service names are not supported (only port numbers)!
*
* @param nodename descriptive name or address string of the host
* (may be NULL -> local address)
* @param servname port number as string of NULL
* @param hints structure containing input values that set socktype and protocol
* @param res pointer to a pointer where to store the result (set to NULL on failure)
* @return 0 on success, non-zero on failure
*
* @todo: implement AI_V4MAPPED, AI_ADDRCONFIG
*/
int
lwip_getaddrinfo(const char *nodename, const char *servname,
const struct addrinfo *hints, struct addrinfo **res)
{
err_t err;
ip_addr_t addr;
struct addrinfo *ai;
struct sockaddr_storage *sa = NULL;
int port_nr = 0;
size_t total_size;
size_t namelen = 0;
int ai_family;
if (res == NULL) {
return EAI_FAIL;
}
*res = NULL;
if ((nodename == NULL) && (servname == NULL)) {
return EAI_NONAME;
}
if (hints != NULL) {
ai_family = hints->ai_family;
if ((ai_family != AF_UNSPEC)
#if LWIP_IPV4
&& (ai_family != AF_INET)
#endif /* LWIP_IPV4 */
#if LWIP_IPV6
&& (ai_family != AF_INET6)
#endif /* LWIP_IPV6 */
) {
return EAI_FAMILY;
}
} else {
ai_family = AF_UNSPEC;
}
if (servname != NULL) {
/* service name specified: convert to port number
* @todo?: currently, only ASCII integers (port numbers) are supported (AI_NUMERICSERV)! */
port_nr = atoi(servname);
if ((port_nr <= 0) || (port_nr > 0xffff)) {
return EAI_SERVICE;
}
}
if (nodename != NULL) {
/* service location specified, try to resolve */
if ((hints != NULL) && (hints->ai_flags & AI_NUMERICHOST)) {
/* no DNS lookup, just parse for an address string */
if (!ipaddr_aton(nodename, &addr)) {
return EAI_NONAME;
}
#if LWIP_IPV4 && LWIP_IPV6
if ((IP_IS_V6_VAL(addr) && ai_family == AF_INET) ||
(IP_IS_V4_VAL(addr) && ai_family == AF_INET6)) {
return EAI_NONAME;
}
#endif /* LWIP_IPV4 && LWIP_IPV6 */
} else {
#if LWIP_IPV4 && LWIP_IPV6
/* AF_UNSPEC: prefer IPv4 */
u8_t type = NETCONN_DNS_IPV4_IPV6;
if (ai_family == AF_INET) {
type = NETCONN_DNS_IPV4;
} else if (ai_family == AF_INET6) {
type = NETCONN_DNS_IPV6;
}
#endif /* LWIP_IPV4 && LWIP_IPV6 */
err = netconn_gethostbyname_addrtype(nodename, &addr, type);
if (err != ERR_OK) {
return EAI_FAIL;
}
}
} else {
/* service location specified, use loopback address */
if ((hints != NULL) && (hints->ai_flags & AI_PASSIVE)) {
ip_addr_set_any(ai_family == AF_INET6, &addr);
} else {
ip_addr_set_loopback(ai_family == AF_INET6, &addr);
}
}
total_size = sizeof(struct addrinfo) + sizeof(struct sockaddr_storage);
if (nodename != NULL) {
namelen = strlen(nodename);
if (namelen > DNS_MAX_NAME_LENGTH) {
/* invalid name length */
return EAI_FAIL;
}
LWIP_ASSERT("namelen is too long", total_size + namelen + 1 > total_size);
total_size += namelen + 1;
}
/* If this fails, please report to lwip-devel! :-) */
LWIP_ASSERT("total_size <= NETDB_ELEM_SIZE: please report this!",
total_size <= NETDB_ELEM_SIZE);
ai = (struct addrinfo *)memp_malloc(MEMP_NETDB);
if (ai == NULL) {
return EAI_MEMORY;
}
memset(ai, 0, total_size);
/* cast through void* to get rid of alignment warnings */
sa = (struct sockaddr_storage *)(void*)((u8_t*)ai + sizeof(struct addrinfo));
if (IP_IS_V6_VAL(addr)) {
#if LWIP_IPV6
struct sockaddr_in6 *sa6 = (struct sockaddr_in6*)sa;
/* set up sockaddr */
inet6_addr_from_ip6addr(&sa6->sin6_addr, ip_2_ip6(&addr));
sa6->sin6_family = AF_INET6;
sa6->sin6_len = sizeof(struct sockaddr_in6);
sa6->sin6_port = lwip_htons((u16_t)port_nr);
ai->ai_family = AF_INET6;
#endif /* LWIP_IPV6 */
} else {
#if LWIP_IPV4
struct sockaddr_in *sa4 = (struct sockaddr_in*)sa;
/* set up sockaddr */
inet4_addr_from_ip4addr(&sa4->sin_addr, ip_2_ip4(&addr));
sa4->sin_family = AF_INET;
sa4->sin_len = sizeof(struct sockaddr_in);
sa4->sin_port = lwip_htons((u16_t)port_nr);
ai->ai_family = AF_INET;
#endif /* LWIP_IPV4 */
}
/* set up addrinfo */
if (hints != NULL) {
/* copy socktype & protocol from hints if specified */
ai->ai_socktype = hints->ai_socktype;
ai->ai_protocol = hints->ai_protocol;
}
if (nodename != NULL) {
/* copy nodename to canonname if specified */
ai->ai_canonname = ((char*)ai + sizeof(struct addrinfo) + sizeof(struct sockaddr_storage));
MEMCPY(ai->ai_canonname, nodename, namelen);
ai->ai_canonname[namelen] = 0;
}
ai->ai_addrlen = sizeof(struct sockaddr_storage);
ai->ai_addr = (struct sockaddr*)sa;
*res = ai;
return 0;
}
/**
* Translates the name of a service location (for example, a host name) and/or
* a service name and returns a set of socket addresses and associated
* information to be used in creating a socket with which to address the
* specified service.
* Memory for the result is allocated internally and must be freed by calling
* lwip_freeaddrinfo()!
*
* Due to a limitation in dns_gethostbyname, only the first address of a
* host is returned.
* Also, service names are not supported (only port numbers)!
*
* @param nodename descriptive name or address string of the host
* (may be NULL -> local address)
* @param servname port number as string of NULL
* @param hints structure containing input values that set socktype and protocol
* @param res pointer to a pointer where to store the result (set to NULL on failure)
* @return 0 on success, non-zero on failure
*/
int
lwip_getaddrinfo(const char *nodename, const char *servname,
const struct addrinfo *hints, struct addrinfo **res)
{
err_t err;
ip_addr_t addr;
struct addrinfo *ai;
struct sockaddr_in *sa = NULL;
int port_nr = 0;
size_t total_size;
size_t namelen = 0;
if (res == NULL) {
return EAI_FAIL;
}
*res = NULL;
if ((nodename == NULL) && (servname == NULL)) {
return EAI_NONAME;
}
if (servname != NULL) {
/* service name specified: convert to port number
* @todo?: currently, only ASCII integers (port numbers) are supported! */
port_nr = atoi(servname);
if ((port_nr <= 0) || (port_nr > 0xffff)) {
return EAI_SERVICE;
}
}
if (nodename != NULL) {
/* service location specified, try to resolve */
err = netconn_gethostbyname(nodename, &addr);
if (err != ERR_OK) {
return EAI_FAIL;
}
} else {
/* service location specified, use loopback address */
ip_addr_set_loopback(&addr);
}
total_size = sizeof(struct addrinfo) + sizeof(struct sockaddr_in);
if (nodename != NULL) {
namelen = strlen(nodename);
LWIP_ASSERT("namelen is too long", (namelen + 1) <= (mem_size_t)-1);
total_size += namelen + 1;
}
/* If this fails, please report to lwip-devel! :-) */
LWIP_ASSERT("total_size <= NETDB_ELEM_SIZE: please report this!",
total_size <= NETDB_ELEM_SIZE);
ai = (struct addrinfo *)memp_malloc(MEMP_NETDB);
if (ai == NULL) {
goto memerr;
}
memset(ai, 0, total_size);
sa = (struct sockaddr_in*)((u8_t*)ai + sizeof(struct addrinfo));
/* set up sockaddr */
inet_addr_from_ipaddr(&sa->sin_addr, &addr);
sa->sin_family = AF_INET;
sa->sin_len = sizeof(struct sockaddr_in);
sa->sin_port = htons((u16_t)port_nr);
/* set up addrinfo */
ai->ai_family = AF_INET;
if (hints != NULL) {
/* copy socktype & protocol from hints if specified */
ai->ai_socktype = hints->ai_socktype;
ai->ai_protocol = hints->ai_protocol;
}
if (nodename != NULL) {
/* copy nodename to canonname if specified */
ai->ai_canonname = ((char*)ai + sizeof(struct addrinfo) + sizeof(struct sockaddr_in));
MEMCPY(ai->ai_canonname, nodename, namelen);
ai->ai_canonname[namelen] = 0;
}
ai->ai_addrlen = sizeof(struct sockaddr_in);
ai->ai_addr = (struct sockaddr*)sa;
*res = ai;
return 0;
memerr:
if (ai != NULL) {
memp_free(MEMP_NETDB, ai);
}
return EAI_MEMORY;
}
