/*!
** @brief Lookup a DAG based using a host or service name.
**
** The name should be a string such as www_s.example.xia or host.example.xia.
** By convention services are indicated by '_s' appended to the service name.
** The memory returned is dynamically allocated and should be released with a
** call to free() when the caller is done with it.
**
** This is a very simple implementation of the name query function.
** It will be replaces in a future release.
**
** @param name The name of an XIA service or host.
**
** @returns a character point to the dag on success
** @returns NULL on failure
**
*/
int XgetDAGbyName(const char *name, sockaddr_x *addr, socklen_t *addrlen)
{
int sock;
sockaddr_x ns_dag;
char pkt[NS_MAX_PACKET_SIZE];
char *dag;
char _name[NS_MAX_DAG_LENGTH], _dag[NS_MAX_DAG_LENGTH];
int result;
if (!addr || !addrlen || *addrlen < sizeof(sockaddr_x)) {
errno = EINVAL;
return -1;
}
// see if name is registered in the local hosts.xia file
if((dag = hostsLookup(name))) {
Graph g(dag);
free(dag);
// check to see if the returned dag was valid
// we may want a better check for this in the future
if (g.num_nodes() > 0) {
std::string s = g.dag_string();
g.fill_sockaddr((sockaddr_x*)addr);
*addrlen = sizeof(sockaddr_x);
return 0;
}
}
// not found locally, check the name server
if ((sock = Xsocket(AF_XIA, SOCK_DGRAM, 0)) < 0)
return -1;
//Read the nameserver DAG (the one that the name-query will be sent to)
if ( XreadNameServerDAG(sock, &ns_dag) < 0 ) {
LOG("Unable to find nameserver address");
errno = NO_RECOVERY;
return -1;
}
//Construct a name-query packet
ns_pkt query_pkt;
query_pkt.type = NS_TYPE_QUERY;
query_pkt.name = strdup(name);
memset(pkt, 0, sizeof(pkt));
int offset = 0;
memcpy(pkt, &query_pkt.type, sizeof(query_pkt.type));
offset += sizeof(query_pkt.type);
memcpy(pkt+offset, query_pkt.name, strlen(query_pkt.name)+1);
offset += strlen(query_pkt.name)+1;
//Send a name query to the name server
Xsendto(sock, pkt, offset, 0, (const struct sockaddr*)&ns_dag, sizeof(sockaddr_x));
//Check the response from the name server
memset(pkt, 0, sizeof(pkt));
int rc = Xrecvfrom(sock, pkt, NS_MAX_PACKET_SIZE, 0, NULL, NULL);
if (rc < 0) { perror("recvfrom"); }
memset(_name, '\0', NS_MAX_DAG_LENGTH);
memset(_dag, '\0', NS_MAX_DAG_LENGTH);
ns_pkt *tmp = (ns_pkt *)pkt;
char* tmp_name = (char*)(pkt+sizeof(tmp->type));
char* tmp_dag = (char*)(pkt+sizeof(tmp->type)+ strlen(tmp_name)+1);
switch (tmp->type) {
case NS_TYPE_RESPONSE:
sprintf(_name, "%s", tmp_name);
sprintf(_dag, "%s", tmp_dag);
result = 1;
break;
case NS_TYPE_RESPONSE_ERROR:
result = -1;
break;
default:
LOG("Unknown nameserver response");
result = -1;
break;
}
Xclose(sock);
free(query_pkt.name);
if (result < 0) {
return result;
}
Graph g(_dag);
g.fill_sockaddr(addr);
return 0;
}
/*!
** @brief Register a service or hostname with the name server.
**
** Register a host or service name with the XIA nameserver.
** By convention services are indicated by '_s' appended to the service name.
** The memory returned is dynamically allocated and should be released with a
** call to free() when the caller is done with it.
**
** This is a very simple implementation and will be replaced in a
** future release. This version does not check correctness of the name or dag,
** nor does it check to ensure that the client is allowed to bind to name.
**
** @param name - The name of an XIA service or host.
** @param DAG - the DAG to be bound to name.
**
** @returns 0 on success
** @returns -1 on failure with errno set
**
*/
int XregisterName(const char *name, sockaddr_x *DAG) {
int sock;
sockaddr_x ns_dag;
char pkt[NS_MAX_PACKET_SIZE];
char _name[NS_MAX_DAG_LENGTH], _dag[NS_MAX_DAG_LENGTH];
int result;
if ((sock = Xsocket(AF_XIA, SOCK_DGRAM, 0)) < 0)
return -1;
//Read the nameserver DAG (the one that the name-registration will be sent to)
if (XreadNameServerDAG(sock, &ns_dag) < 0) {
LOG("Unable to find nameserver address");
errno = NO_RECOVERY;
return -1;
}
if (!DAG) {
errno = EINVAL;
return -1;
}
Graph g(DAG);
if (g.num_nodes() <= 0) {
errno = EINVAL;
return -1;
}
//Construct a registration packet
ns_pkt register_pkt;
register_pkt.type = NS_TYPE_REGISTER;
register_pkt.name = strdup(name);
register_pkt.dag = strdup(g.dag_string().c_str());
memset(pkt, 0, sizeof(pkt));
int offset = 0;
memcpy(pkt, ®ister_pkt.type, sizeof(register_pkt.type));
offset += sizeof(register_pkt.type);
memcpy(pkt+offset, register_pkt.name, strlen(register_pkt.name)+1);
offset += strlen(register_pkt.name)+1;
memcpy(pkt+offset, register_pkt.dag, strlen(register_pkt.dag)+1);
offset += strlen(register_pkt.dag)+1;
//Send the name registration packet to the name server
//FIXME: use sockaddr here
Xsendto(sock, pkt, offset, 0, (const struct sockaddr *)&ns_dag, sizeof(sockaddr_x));
//Check the response from the name server
memset(pkt, 0, sizeof(pkt));
int rc = Xrecvfrom(sock, pkt, NS_MAX_PACKET_SIZE, 0, NULL, NULL);
if (rc < 0) { perror("recvfrom"); }
memset(_name, '\0', NS_MAX_DAG_LENGTH);
memset(_dag, '\0', NS_MAX_DAG_LENGTH);
ns_pkt *tmp = (ns_pkt *)pkt;
char* tmp_name = (char*)(pkt+sizeof(tmp->type));
char* tmp_dag = (char*)(pkt+sizeof(tmp->type)+ strlen(tmp_name)+1);
switch (tmp->type) {
case NS_TYPE_RESPONSE:
sprintf(_name, "%s", tmp_name);
sprintf(_dag, "%s", tmp_dag);
result = 0;
break;
case NS_TYPE_RESPONSE_ERROR:
result = -1;
break;
default:
fprintf(stderr, "dafault\n");
result = -1;
break;
}
free(register_pkt.name);
free(register_pkt.dag);
Xclose(sock);
return result;
}
/*!
** @brief Lookup a DAG based using a host or service name.
**
** The name should be a string such as www_s.example.xia or host.example.xia.
** By convention services are indicated by '_s' appended to the service name.
** The memory returned is dynamically allocated and should be released with a
** call to free() when the caller is done with it.
**
** This is a very simple implementation of the name query function.
** It will be replaces in a future release.
**
** @param name The name of an XIA service or host.
**
** @returns a character point to the dag on success
** @returns NULL on failure
**
*/
char *XgetDAGbyName(const char *name) {
int sock;
char pkt[NS_MAX_PACKET_SIZE],ddag[NS_MAX_PACKET_SIZE], ns_dag[NS_MAX_PACKET_SIZE];
char *dag;
char _name[NS_MAX_DAG_LENGTH], _dag[NS_MAX_DAG_LENGTH];
int result;
//Open socket
sock=Xsocket(XSOCK_DGRAM);
//Read the nameserver DAG (the one that the name-query will be sent to)
if ( XreadNameServerDAG(sock, ns_dag) < 0 )
error("Reading nameserver address");
//Construct a name-query packet
ns_pkt query_pkt;
query_pkt.type = NS_TYPE_QUERY;
query_pkt.name = (char*)malloc(strlen(name)+1);
sprintf(query_pkt.name, "%s", name);
//query_pkt.dag = (char*)malloc(strlen(DAG)+1);
//sprintf(query_pkt.dag, "%s", DAG);
memset(pkt, 0, sizeof(pkt));
int offset = 0;
memcpy(pkt, &query_pkt.type, sizeof(query_pkt.type));
offset += sizeof(query_pkt.type);
memcpy(pkt+offset, query_pkt.name, strlen(query_pkt.name)+1);
offset += strlen(query_pkt.name)+1;
//memcpy(pkt+offset, query_pkt.dag, strlen(query_pkt.dag)+1);
//offset += strlen(query_pkt.dag)+1;
//Send a name query to the name server
Xsendto(sock, pkt, offset, 0, ns_dag, strlen(ns_dag)+1);
//Check the response from the name server
memset(pkt, 0, sizeof(pkt));
memset(ddag, 0, sizeof(ddag));
size_t ddaglen = sizeof(ddag);
int rc = Xrecvfrom(sock, pkt, NS_MAX_PACKET_SIZE, 0, ddag, &ddaglen);
if (rc < 0) { error("recvfrom"); }
memset(_name, '\0', NS_MAX_DAG_LENGTH);
memset(_dag, '\0', NS_MAX_DAG_LENGTH);
ns_pkt *tmp = (ns_pkt *)pkt;
char* tmp_name = (char*)(pkt+sizeof(tmp->type));
char* tmp_dag = (char*)(pkt+sizeof(tmp->type)+ strlen(tmp_name)+1);
switch (tmp->type) {
case NS_TYPE_RESPONSE:
sprintf(_name, "%s", tmp_name);
sprintf(_dag, "%s", tmp_dag);
result = 1;
break;
case NS_TYPE_RESPONSE_ERROR:
result = -1;
break;
default:
fprintf(stderr, "dafault\n");
result = -1;
break;
}
if (result < 0) {
return NULL;
}
dag = (char*)malloc(sizeof(_dag) + 1);
strcpy(dag, _dag);
//Close socket
Xclose(sock);
free(query_pkt.name);
return dag;
}
