umdnsd: Replace strerror(errno) with %m.
[project/mdnsd.git] / service.c
index 32c3d62..97b6f91 100644 (file)
--- a/service.c
+++ b/service.c
 #include <arpa/nameser.h>
 #include <sys/socket.h>
 
-#include <ifaddrs.h>
 #include <resolv.h>
 #include <glob.h>
 #include <stdio.h>
 #include <time.h>
 
-#include <uci.h>
-#include <uci_blob.h>
-
 #include <libubus.h>
 #include <libubox/vlist.h>
 #include <libubox/uloop.h>
@@ -38,6 +34,7 @@
 #include "announce.h"
 
 enum {
+       SERVICE_INSTANCE,
        SERVICE_SERVICE,
        SERVICE_PORT,
        SERVICE_TXT,
@@ -50,6 +47,7 @@ struct service {
        time_t t;
 
        const char *id;
+       const char *instance;
        const char *service;
        const uint8_t *txt;
        int txt_len;
@@ -58,6 +56,7 @@ struct service {
 };
 
 static const struct blobmsg_policy service_policy[__SERVICE_MAX] = {
+       [SERVICE_INSTANCE] = { .name = "instance", .type = BLOBMSG_TYPE_STRING },
        [SERVICE_SERVICE] = { .name = "service", .type = BLOBMSG_TYPE_STRING },
        [SERVICE_PORT] = { .name = "port", .type = BLOBMSG_TYPE_INT32 },
        [SERVICE_TXT] = { .name = "txt", .type = BLOBMSG_TYPE_ARRAY },
@@ -69,16 +68,23 @@ service_update(struct vlist_tree *tree, struct vlist_node *node_new,
 
 static struct blob_buf b;
 static VLIST_TREE(services, avl_strcmp, service_update, false, false);
-static char *sdudp =  "_services._dns-sd._udp.local";
-static char *sdtcp =  "_services._dns-sd._tcp.local";
 static int service_init_announce;
 
+/**
+ * service_instance_name - construct Service Instance Name as in RFC 6763
+ *
+ * RFC 6763 specifies Service Instance Names in the following way:
+ *
+ * Service Instance Name = <Instance> . <Service> . <Domain>
+ *
+ * @s: service to generate service instance name for
+ */
 static const char *
-service_name(const char *domain)
+service_instance_name(struct service *s)
 {
        static char buffer[256];
 
-       snprintf(buffer, sizeof(buffer), "%s.%s", mdns_hostname, domain);
+       snprintf(buffer, sizeof(buffer), "%s.%s", s->instance, s->service);
 
        return buffer;
 }
@@ -110,121 +116,75 @@ service_add_srv(struct service *s, int ttl)
 
 #define TOUT_LOOKUP    60
 
-static int
+static time_t
 service_timeout(struct service *s)
 {
-       time_t t = time(NULL);
+       time_t t = monotonic_time();
 
-       if (t - s->t <= TOUT_LOOKUP)
+       if (t - s->t <= TOUT_LOOKUP) {
+               DBG(2, "t=%lu, s->t=%lu, t - s->t = %lu\n", t, s->t, t - s->t);
                return 0;
-
-       s->t = t;
-
-       return 1;
-}
-
-void
-service_reply_a(struct interface *iface, int type, int ttl)
-{
-       struct ifaddrs *ifap, *ifa;
-       struct sockaddr_in *sa;
-       struct sockaddr_in6 *sa6;
-
-       getifaddrs(&ifap);
-
-       dns_init_answer();
-       for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
-               if (strcmp(ifa->ifa_name, iface->name))
-                       continue;
-               if (ifa->ifa_addr->sa_family==AF_INET) {
-                       sa = (struct sockaddr_in *) ifa->ifa_addr;
-                       dns_add_answer(TYPE_A, (uint8_t *) &sa->sin_addr, 4, ttl);
-               }
-               if (ifa->ifa_addr->sa_family==AF_INET6) {
-                       uint8_t ll_prefix[] = {0xfe, 0x80 };
-                       sa6 = (struct sockaddr_in6 *) ifa->ifa_addr;
-                       if (!memcmp(&sa6->sin6_addr, &ll_prefix, 2))
-                               dns_add_answer(TYPE_AAAA, (uint8_t *) &sa6->sin6_addr, 16, ttl);
-               }
        }
-       dns_send_answer(iface, mdns_hostname_local);
 
-       freeifaddrs(ifap);
+       return t;
 }
 
 static void
-service_reply_single(struct interface *iface, struct service *s, const char *match, int ttl, int force)
+service_reply_single(struct interface *iface, struct sockaddr *to, struct service *s, int ttl, int force)
 {
-       const char *host = service_name(s->service);
+       const char *host = service_instance_name(s);
        char *service = strstr(host, "._");
+       time_t t = service_timeout(s);
+
 
-       if (!force && (!s->active || !service || !service_timeout(s)))
+       if (!force && (!s->active || !service || !t))
                return;
 
        service++;
 
-       if (match && strcmp(match, s->service))
-               return;
+       s->t = t;
 
        dns_init_answer();
-       service_add_ptr(service_name(s->service), ttl);
-       dns_send_answer(iface, service);
+       service_add_ptr(service_instance_name(s), ttl);
+       dns_send_answer(iface, to, service);
 
        dns_init_answer();
        service_add_srv(s, ttl);
        if (s->txt && s->txt_len)
                dns_add_answer(TYPE_TXT, (uint8_t *) s->txt, s->txt_len, ttl);
-       dns_send_answer(iface, host);
+       dns_send_answer(iface, to, host);
 }
 
 void
-service_reply(struct interface *iface, const char *match, int ttl)
+service_reply(struct interface *iface, struct sockaddr *to, const char *instance, const char *service_domain, int ttl)
 {
        struct service *s;
 
-       vlist_for_each_element(&services, s, node)
-               service_reply_single(iface, s, match, ttl, 0);
-
-       if (match)
-               return;
-
-       service_reply_a(iface, TYPE_A, ttl);
+       vlist_for_each_element(&services, s, node) {
+               if (instance && strcmp(s->instance, instance))
+                       continue;
+               if (service_domain && strcmp(s->service, service_domain))
+                       continue;
+               service_reply_single(iface, to, s, ttl, 0);
+       }
 }
 
 void
-service_announce_services(struct interface *iface, const char *service)
+service_announce_services(struct interface *iface, struct sockaddr *to, int ttl)
 {
        struct service *s;
-       int tcp = 1;
-
-       if (!strcmp(service, sdudp))
-               tcp = 0;
-       else if (strcmp(service, sdtcp))
-               return;
 
        vlist_for_each_element(&services, s, node) {
-               if (!strstr(s->service, "._tcp") && tcp)
-                       continue;
-               if (!strstr(s->service, "._udp") && !tcp)
-                       continue;
                s->t = 0;
-               dns_init_answer();
-               service_add_ptr(s->service, announce_ttl);
-               if (tcp)
-                       dns_send_answer(iface, sdtcp);
-               else
-                       dns_send_answer(iface, sdudp);
-               service_reply(iface, s->service, announce_ttl);
+               if (ttl) {
+                       dns_init_answer();
+                       service_add_ptr(s->service, ttl);
+                       dns_send_answer(iface, to, C_DNS_SD);
+               }
+               service_reply_single(iface, to, s, ttl, 0);
        }
 }
 
-void
-service_announce(struct interface *iface)
-{
-       service_announce_services(iface, sdudp);
-       service_announce_services(iface, sdtcp);
-}
-
 static void
 service_update(struct vlist_tree *tree, struct vlist_node *node_new,
               struct vlist_node *node_old)
@@ -237,7 +197,7 @@ service_update(struct vlist_tree *tree, struct vlist_node *node_new,
                if (service_init_announce)
                        vlist_for_each_element(&interfaces, iface, node) {
                                s->t = 0;
-                               service_reply_single(iface, s, NULL, announce_ttl, 1);
+                               service_reply_single(iface, NULL, s, announce_ttl, 1);
                        }
                return;
        }
@@ -245,7 +205,7 @@ service_update(struct vlist_tree *tree, struct vlist_node *node_new,
        s = container_of(node_old, struct service, node);
        if (!node_new && service_init_announce)
                vlist_for_each_element(&interfaces, iface, node)
-                       service_reply_single(iface, s, NULL, 0, 1);
+                       service_reply_single(iface, NULL, s, 0, 1);
        free(s);
 }
 
@@ -254,7 +214,7 @@ service_load_blob(struct blob_attr *b)
 {
        struct blob_attr *txt, *_tb[__SERVICE_MAX];
        struct service *s;
-       char *d_service, *d_id;
+       char *d_instance, *d_service, *d_id;
        uint8_t *d_txt;
        int rem2;
        int txt_len = 0;
@@ -264,12 +224,13 @@ service_load_blob(struct blob_attr *b)
        if (!_tb[SERVICE_PORT] || !_tb[SERVICE_SERVICE])
                return;
 
-       if (_tb[SERVICE_SERVICE])
+       if (_tb[SERVICE_TXT])
                blobmsg_for_each_attr(txt, _tb[SERVICE_TXT], rem2)
                        txt_len += 1 + strlen(blobmsg_get_string(txt));
 
        s = calloc_a(sizeof(*s),
                &d_id, strlen(blobmsg_name(b)) + 1,
+               &d_instance, _tb[SERVICE_INSTANCE] ? strlen(blobmsg_get_string(_tb[SERVICE_INSTANCE])) + 1 : 0,
                &d_service, strlen(blobmsg_get_string(_tb[SERVICE_SERVICE])) + 1,
                &d_txt, txt_len);
        if (!s)
@@ -277,13 +238,17 @@ service_load_blob(struct blob_attr *b)
 
        s->port = blobmsg_get_u32(_tb[SERVICE_PORT]);
        s->id = strcpy(d_id, blobmsg_name(b));
+       if (_tb[SERVICE_INSTANCE])
+               s->instance = strcpy(d_instance, blobmsg_get_string(_tb[SERVICE_INSTANCE]));
+       else
+               s->instance = umdns_host_label;
        s->service = strcpy(d_service, blobmsg_get_string(_tb[SERVICE_SERVICE]));
        s->active = 1;
        s->t = 0;
        s->txt_len = txt_len;
        s->txt = d_txt;
 
-       if (_tb[SERVICE_SERVICE])
+       if (_tb[SERVICE_TXT])
                blobmsg_for_each_attr(txt, _tb[SERVICE_TXT], rem2) {
                        int len = strlen(blobmsg_get_string(txt));
                        if (!len)
@@ -311,9 +276,12 @@ service_load(char *path)
 
        for (i = 0; i < gl.gl_pathc; i++) {
                blob_buf_init(&b, 0);
-               if (blobmsg_add_json_from_file(&b, gl.gl_pathv[i]))
+               if (blobmsg_add_json_from_file(&b, gl.gl_pathv[i])) {
                        blob_for_each_attr(cur, b.head, rem)
                                service_load_blob(cur);
+               } else {
+                       fprintf(stderr, "Error reading %s JSON\n", gl.gl_pathv[i]);
+               }
        }
        globfree(&gl);
 }
@@ -327,7 +295,7 @@ service_init_cb(struct ubus_request *req, int type, struct blob_attr *msg)
        get_hostname();
 
        vlist_update(&services);
-       service_load("/tmp/run/mdns/*");
+       service_load("/etc/umdns/*");
 
        blob_for_each_attr(cur, msg, rem) {
                struct blob_attr *cur2;