resolved: add a DNS client stub resolver

Let's turn resolved into a something truly useful: a fully asynchronous
DNS stub resolver that subscribes to network changes.

(More to come: caching, LLMNR, mDNS/DNS-SD, DNSSEC, IDN, NSS module)

4 files changed, 30 insertions, 0 deletions

diff --git a/src/shared/bus-errors.h b/src/shared/bus-errors.h
index 48a2b4ef1b..388b42b4fd 100644
--- a/src/shared/bus-errors.h
+++ b/src/shared/bus-errors.h
@@ -59,3 +59,7 @@
 #define BUS_ERROR_AUTOMATIC_TIME_SYNC_ENABLED "org.freedesktop.timedate1.AutomaticTimeSyncEnabled"
 
 #define BUS_ERROR_NO_SUCH_PROCESS "org.freedesktop.systemd1.NoSuchProcess"
+
+#define BUS_ERROR_NO_NAME_SERVERS "org.freedesktop.resolve1.NoNameServers"
+#define BUS_ERROR_INVALID_REPLY "org.freedesktop.resolve1.InvalidReply"
+#define _BUS_ERROR_DNS "org.freedesktop.resolve1.DnsError."
diff --git a/src/shared/in-addr-util.c b/src/shared/in-addr-util.c
index 98d2446e5d..6ece85e37d 100644
--- a/src/shared/in-addr-util.c
+++ b/src/shared/in-addr-util.c
@@ -209,3 +209,25 @@ int in_addr_from_string(unsigned family, const char *s, union in_addr_union *ret
 
         return 0;
 }
+
+int in_addr_from_string_auto(const char *s, unsigned *family, union in_addr_union *ret) {
+        int r;
+
+        assert(s);
+        assert(family);
+        assert(ret);
+
+        r = in_addr_from_string(AF_INET, s, ret);
+        if (r >= 0) {
+                *family = AF_INET;
+                return 0;
+        }
+
+        r = in_addr_from_string(AF_INET6, s, ret);
+        if (r >= 0) {
+                *family = AF_INET6;
+                return 0;
+        }
+
+        return -EINVAL;
+}
diff --git a/src/shared/in-addr-util.h b/src/shared/in-addr-util.h
index ae3aa9021d..108f1f3ace 100644
--- a/src/shared/in-addr-util.h
+++ b/src/shared/in-addr-util.h
@@ -37,6 +37,7 @@ int in_addr_prefix_intersect(unsigned family, const union in_addr_union *a, unsi
 int in_addr_prefix_next(unsigned family, union in_addr_union *u, unsigned prefixlen);
 int in_addr_to_string(unsigned family, const union in_addr_union *u, char **ret);
 int in_addr_from_string(unsigned family, const char *s, union in_addr_union *ret);
+int in_addr_from_string_auto(const char *s, unsigned *family, union in_addr_union *ret);
 
 static inline size_t PROTO_ADDRESS_SIZE(int proto) {
         assert(proto == AF_INET || proto == AF_INET6);
diff --git a/src/shared/macro.h b/src/shared/macro.h
index 70c5fb50a7..5619c32e45 100644
--- a/src/shared/macro.h
+++ b/src/shared/macro.h
@@ -241,6 +241,9 @@ static inline unsigned long ALIGN_POWER2(unsigned long u) {
 #define PTR_TO_UINT64(p) ((uint64_t) ((uintptr_t) (p)))
 #define UINT64_TO_PTR(u) ((void *) ((uintptr_t) (u)))
 
+#define PTR_TO_SIZE(p) ((size_t) ((uintptr_t) (p)))
+#define SIZE_TO_PTR(u) ((void *) ((uintptr_t) (u)))
+
 #define memzero(x,l) (memset((x), 0, (l)))
 #define zero(x) (memzero(&(x), sizeof(x)))