-/* authd/dns.h - header for authd DNS functions
+/* authd/dns.c - authd DNS functions
* Copyright (c) 2016 William Pitcock <nenolod@dereferenced.org>
*
* Permission to use, copy, modify, and/or distribute this software for any
#include "authd.h"
#include "dns.h"
+#include "notice.h"
+#include "res.h"
-static void
-submit_dns_answer(void *userdata, struct DNSReply *reply)
+static void handle_lookup_ip_reply(void *data, struct DNSReply *reply);
+static void handle_lookup_hostname_reply(void *data, struct DNSReply *reply);
+
+uint64_t query_count = 0;
+
+/* A bit different from ircd... you just get a dns_query object.
+ *
+ * It gets freed whenever the res code gets back to us.
+ */
+struct dns_query *
+lookup_ip(const char *host, int aftype, DNSCB callback, void *data)
{
- struct dns_request *req = userdata;
- char response[64] = "*";
- char status = 'E';
+ struct dns_query *query = rb_malloc(sizeof(struct dns_query));
+ int g_type;
- if (reply == NULL)
+ if(aftype == AF_INET)
+ {
+ query->type = QUERY_A;
+ g_type = T_A;
+ }
+ else if(aftype == AF_INET6)
{
- rb_helper_write(authd_helper, "E %s E %c *\n", req->reqid, req->type);
- goto cleanup;
+ query->type = QUERY_AAAA;
+ g_type = T_AAAA;
}
+ else
+ {
+ rb_free(query);
+ return NULL;
+ }
+
+ query->id = query_count++;
+ query->callback = callback;
+ query->data = data;
+
+ query->query.ptr = query;
+ query->query.callback = handle_lookup_ip_reply;
+
+ gethost_byname_type(host, &query->query, g_type);
+
+ return query;
+}
- switch (req->type)
+/* See lookup_ip's comment */
+struct dns_query *
+lookup_hostname(const char *ip, DNSCB callback, void *data)
+{
+ struct dns_query *query = rb_malloc(sizeof(struct dns_query));
+ int aftype;
+
+ if(!rb_inet_pton_sock(ip, (struct sockaddr *)&query->addr))
{
- case '4':
- if (GET_SS_FAMILY(&reply->addr) == AF_INET)
- {
- status = 'O';
- rb_inet_ntop_sock((struct sockaddr *) &reply->addr, response, sizeof(response));
- }
- break;
-#ifdef RB_IPV6
- case '6':
- if (GET_SS_FAMILY(&reply->addr) == AF_INET6)
- {
- char tmpres[63];
- rb_inet_ntop_sock((struct sockaddr *) &reply->addr, tmpres, sizeof(tmpres));
+ rb_free(query);
+ return NULL;
+ }
- if (*tmpres == ':')
- {
- rb_strlcpy(response, "0", sizeof(response));
- rb_strlcat(response, tmpres, sizeof(response));
- }
- else
- rb_strlcpy(response, tmpres, sizeof(response));
+ aftype = GET_SS_FAMILY(&query->addr);
- status = 'O';
- }
- break;
-#endif
- case 'R':
- {
- struct sockaddr_in *ip, *ip_fwd;
- ip = (struct sockaddr_in *) &req->addr;
- ip_fwd = (struct sockaddr_in *) &reply->addr;
+ if(aftype == AF_INET)
+ query->type = QUERY_PTR_A;
+ else if(aftype == AF_INET6)
+ query->type = QUERY_PTR_AAAA;
+ else
+ {
+ rb_free(query);
+ return NULL;
+ }
- if(ip->sin_addr.s_addr == ip_fwd->sin_addr.s_addr && strlen(reply->h_name) < 63)
- {
- rb_strlcpy(response, reply->h_name, sizeof(response));
- status = 'O';
- }
- }
+ query->id = query_count++;
+ query->callback = callback;
+ query->data = data;
+
+ query->query.ptr = query;
+ query->query.callback = handle_lookup_hostname_reply;
+
+ gethost_byaddr(&query->addr, &query->query);
+
+ return query;
+}
+
+/* Cancel a pending query */
+void
+cancel_query(struct dns_query *query)
+{
+ query->callback = query->data = NULL;
+}
+
+/* Callback from gethost_byname_type */
+static void
+handle_lookup_ip_reply(void *data, struct DNSReply *reply)
+{
+ struct dns_query *query = data;
+ char ip[HOSTIPLEN] = "*";
+
+ if(query == NULL)
+ {
+ /* Shouldn't happen */
+ warn_opers(L_CRIT, "DNS: handle_lookup_ip_reply: query == NULL!");
+ exit(EX_DNS_ERROR);
+ }
+
+ if(reply == NULL)
+ goto end;
+
+ switch(query->type)
+ {
+ case QUERY_A:
+ if(GET_SS_FAMILY(&reply->addr) == AF_INET)
+ rb_inet_ntop_sock((struct sockaddr *)&reply->addr, ip, sizeof(ip));
break;
-#ifdef RB_IPV6
- case 'S':
+ case QUERY_AAAA:
+ if(GET_SS_FAMILY(&reply->addr) == AF_INET6)
{
- struct sockaddr_in6 *ip, *ip_fwd;
- ip = (struct sockaddr_in6 *) &req->addr;
- ip_fwd = (struct sockaddr_in6 *) &reply->addr;
-
- if(memcmp(&ip->sin6_addr, &ip_fwd->sin6_addr, sizeof(struct in6_addr)) == 0 && strlen(reply->h_name) < 63)
+ rb_inet_ntop_sock((struct sockaddr *)&reply->addr, ip, sizeof(ip));
+ if(ip[0] == ':')
{
- rb_strlcpy(response, reply->h_name, sizeof(response));
- status = 'O';
+ memmove(&ip[1], ip, strlen(ip));
+ ip[0] = '0';
}
}
break;
-#endif
default:
- exit(7);
+ warn_opers(L_CRIT, "DNS: handle_lookup_ip_reply: unknown query type %d",
+ query->type);
+ exit(EX_DNS_ERROR);
}
- rb_helper_write(authd_helper, "E %s %c %c %s\n", req->reqid, status, req->type, response);
-cleanup:
- rb_free(req);
+end:
+ if(query->callback)
+ query->callback(ip, ip[0] != '*', query->type, query->data);
+
+ rb_free(query);
}
-void
-resolve_dns(int parc, char *parv[])
+/* Callback from gethost_byaddr */
+static void
+handle_lookup_hostname_reply(void *data, struct DNSReply *reply)
{
- struct dns_request *req;
- char *requestid = parv[1];
- char *qtype = parv[2];
- char *rec = parv[3];
- int type;
+ struct dns_query *query = data;
+ char *hostname = NULL;
+
+ if(query == NULL)
+ {
+ /* Shouldn't happen */
+ warn_opers(L_CRIT, "DNS: handle_lookup_hostname_reply: query == NULL!");
+ exit(EX_DNS_ERROR);
+ }
- req = rb_malloc(sizeof(*req));
- rb_strlcpy(req->reqid, requestid, sizeof(req->reqid));
- req->type = *qtype;
+ if(reply == NULL)
+ goto end;
- switch (req->type)
+ if(query->type == QUERY_PTR_A)
+ {
+ struct sockaddr_in *ip, *ip_fwd;
+ ip = (struct sockaddr_in *) &query->addr;
+ ip_fwd = (struct sockaddr_in *) &reply->addr;
+
+ if(ip->sin_addr.s_addr == ip_fwd->sin_addr.s_addr)
+ hostname = reply->h_name;
+ }
+ else if(query->type == QUERY_PTR_AAAA)
+ {
+ struct sockaddr_in6 *ip, *ip_fwd;
+ ip = (struct sockaddr_in6 *) &query->addr;
+ ip_fwd = (struct sockaddr_in6 *) &reply->addr;
+
+ if(memcmp(&ip->sin6_addr, &ip_fwd->sin6_addr, sizeof(struct in6_addr)) == 0)
+ hostname = reply->h_name;
+ }
+ else
+ {
+ /* Shouldn't happen */
+ warn_opers(L_CRIT, "DNS: handle_lookup_hostname_reply: unknown query type %d",
+ query->type);
+ exit(EX_DNS_ERROR);
+ }
+end:
+ if(query->callback)
+ query->callback(hostname, hostname != NULL, query->type, query->data);
+
+ rb_free(query);
+}
+
+static void
+submit_dns_answer(const char *reply, bool status, query_type type, void *data)
+{
+ char *id = data;
+
+ if(!id || type == QUERY_INVALID)
+ {
+ warn_opers(L_CRIT, "DNS: submit_dns_answer gave us a bad query");
+ exit(EX_DNS_ERROR);
+ }
+
+ if(reply == NULL || status == false)
+ {
+ rb_helper_write(authd_helper, "E %s E %c *", id, type);
+ rb_free(id);
+ return;
+ }
+
+ rb_helper_write(authd_helper, "E %s O %c %s", id, type, reply);
+ rb_free(id);
+}
+
+void
+handle_resolve_dns(int parc, char *parv[])
+{
+ char *id = rb_strdup(parv[1]);
+ char qtype = *parv[2];
+ char *record = parv[3];
+ int aftype = AF_INET;
+
+ switch(qtype)
{
- case '4':
- type = T_A;
- break;
case '6':
- type = T_AAAA;
+ aftype = AF_INET6;
+ case '4':
+ if(!lookup_ip(record, aftype, submit_dns_answer, id))
+ submit_dns_answer(NULL, false, qtype, NULL);
break;
- case 'R':
case 'S':
- if(!rb_inet_pton_sock(rec, (struct sockaddr *) &req->addr))
- exit(6);
- type = T_PTR;
+ case 'R':
+ if(!lookup_hostname(record, submit_dns_answer, id))
+ submit_dns_answer(NULL, false, qtype, NULL);
break;
+ default:
+ warn_opers(L_CRIT, "DNS: handle_resolve_dns got an unknown query: %c", qtype);
+ exit(EX_DNS_ERROR);
}
+}
- req->query.ptr = req;
- req->query.callback = submit_dns_answer;
+void
+enumerate_nameservers(uint32_t rid, const char letter)
+{
+ char buf[(HOSTIPLEN + 1) * IRCD_MAXNS];
+ size_t s = 0;
- if (type != T_PTR)
- gethost_byname_type(rec, &req->query, type);
- else
- gethost_byaddr(&req->addr, &req->query);
+ if (!irc_nscount)
+ {
+ /* Shouldn't happen */
+ warn_opers(L_CRIT, "DNS: no name servers!");
+ stats_error(rid, letter, "NONAMESERVERS");
+ exit(EX_DNS_ERROR);
+ }
+
+ for(int i = 0; i < irc_nscount; i++)
+ {
+ char addr[HOSTIPLEN];
+ size_t addrlen;
+
+ rb_inet_ntop_sock((struct sockaddr *)&irc_nsaddr_list[i], addr, sizeof(addr));
+
+ if (!addr[0])
+ {
+ /* Shouldn't happen */
+ warn_opers(L_CRIT, "DNS: bad nameserver!");
+ stats_error(rid, letter, "INVALIDNAMESERVER");
+ exit(EX_DNS_ERROR);
+ }
+
+ addrlen = strlen(addr) + 1;
+ (void)snprintf(&buf[s], sizeof(buf) - s, "%s ", addr);
+ s += addrlen;
+ }
+
+ if(s > 0)
+ buf[--s] = '\0';
+
+ stats_result(rid, letter, "%s", buf);
+}
+
+void
+reload_nameservers(const char letter)
+{
+ /* Not a whole lot to it */
+ restart_resolver();
}