resolver: Log reason for DNS resolution failure

[secnet.git] / secnet.h

diff --git a/secnet.h b/secnet.h
index 44b180f043d04baa27ac6cc8155f13cbc69067e6..a38b77c00f6f78e3bbe94a3683222f554afe0905 100644 (file)
--- a/secnet.h
+++ b/secnet.h
@@ -3,16 +3,27 @@
 #ifndef secnet_h
 #define secnet_h
 
+#define ADNS_FEATURE_MANYAF
+
 #include "config.h"
 #include <stdlib.h>
 #include <stdarg.h>
 #include <stdio.h>
 #include <string.h>
 #include <assert.h>
+#include <fcntl.h>
+#include <unistd.h>
 #include <sys/poll.h>
 #include <sys/types.h>
 #include <sys/time.h>
 #include <netinet/in.h>
+#include <arpa/inet.h>
+
+#define MAX_PEER_ADDRS 5
+/* send at most this many copies; honour at most that many addresses */
+
+struct comm_if;
+struct comm_addr;
 
 typedef char *string_t;
 typedef const char *cstring_t;
@@ -21,6 +32,14 @@ typedef const char *cstring_t;
 #define True  (_Bool)1
 typedef _Bool bool_t;
 
+union iaddr {
+    struct sockaddr sa;
+    struct sockaddr_in sin;
+#ifdef CONFIG_IPV6
+    struct sockaddr_in6 sin6;
+#endif
+};
+
 #define ASSERT(x) do { if (!(x)) { fatal("assertion failed line %d file " \
                                         __FILE__,__LINE__); } } while(0)
 
@@ -97,7 +116,7 @@ extern cstring_t *dict_keys(dict_t *dict);
 
 /* List-manipulation functions */
 extern list_t *list_new(void);
-extern int32_t list_length(list_t *a);
+extern int32_t list_length(const list_t *a);
 extern list_t *list_append(list_t *a, item_t *i);
 extern list_t *list_append_list(list_t *a, list_t *b);
 /* Returns an item from the list (index starts at 0), or NULL */
@@ -136,6 +155,9 @@ extern char *safe_strdup(const char *string, const char *message);
 extern void *safe_malloc(size_t size, const char *message);
 extern void *safe_malloc_ary(size_t size, size_t count, const char *message);
 
+void setcloexec(int fd); /* cannot fail */
+void pipe_cloexec(int fd[2]); /* pipe(), setcloexec() twice; cannot fail */
+
 extern int sys_cmd(const char *file, const char *argc, ...);
 
 extern uint64_t now_global;
@@ -272,9 +294,10 @@ struct buffer_if;
    type. 'address' will be NULL if there was a problem with the query. It
    will be freed once resolve_answer_fn returns. It is in network byte
    order. */
-/* XXX extend to be able to provide multiple answers */
-typedef void resolve_answer_fn(void *st, struct in_addr *addr);
+typedef void resolve_answer_fn(void *st, const struct comm_addr *addrs,
+                              int naddrs, const char *failwhy);
 typedef bool_t resolve_request_fn(void *st, cstring_t name,
+                                 int remoteport, struct comm_if *comm,
                                  resolve_answer_fn *cb, void *cst);
 struct resolver_if {
     void *st;
@@ -320,7 +343,8 @@ struct comm_addr {
        must start by memsetting it with FILLZERO, or some
        equivalent. */
     struct comm_if *comm;
-    struct sockaddr_in sin;
+    union iaddr ia;
+    int ix;
 };
 
 /* Return True if the packet was processed, and shouldn't be passed to
@@ -333,6 +357,9 @@ typedef void comm_release_notify_fn(void *commst, void *nst,
                                    comm_notify_fn *fn);
 typedef bool_t comm_sendmsg_fn(void *commst, struct buffer_if *buf,
                               const struct comm_addr *dest);
+  /* Only returns false if (we know that) the local network
+   * environment is such that this address cannot work; transient
+   * or unknown/unexpected failures return true. */
 typedef const char *comm_addr_to_string_fn(void *commst,
                                           const struct comm_addr *ca);
         /* Returned string is in a static buffer. */
@@ -344,6 +371,11 @@ struct comm_if {
     comm_addr_to_string_fn *addr_to_string;
 };
 
+static inline const char *comm_addr_to_string(const struct comm_addr *ca)
+{
+    return ca->comm->addr_to_string(ca->comm->st, ca);
+}
+
 /* LOG interface */
 
 #define LOG_MESSAGE_BUFLEN 1023
@@ -494,7 +526,7 @@ struct buffer_if {
     uint8_t *base;
     uint8_t *start;
     int32_t size; /* Size of buffer contents */
-    int32_t len; /* Total length allocated at base */
+    int32_t alloclen; /* Total length allocated at base */
 };
 
 /***** LOG functions *****/
@@ -540,5 +572,19 @@ extern void log_from_fd(int fd, cstring_t prefix, struct log_if *log);
 #define STRING(x) STRING2(x)
 
 #define FILLZERO(obj) (memset(&(obj),0,sizeof((obj))))
+#define ARRAY_SIZE(ary) (sizeof(ary)/sizeof(ary[0]))
+
+/*
+ * void COPY_OBJ(  OBJECT& dst, const OBJECT& src);
+ * void COPY_ARRAY(OBJECT *dst, const OBJECT *src, INTEGER count);
+ *   // Typesafe: we check that the type OBJECT is the same in both cases.
+ *   // It is OK to use COPY_OBJ on an array object, proviced it's
+ *   // _actually_ the whole array object and not decayed into a
+ *   // pointer (e.g. a formal parameter).
+ */
+#define COPY_OBJ(dst,src) \
+    (&(dst)==&(src), memcpy(&(dst),&(src),sizeof((dst))))
+#define COPY_ARRAY(dst,src,count) \
+    (&(dst)[0]==&(src)[0], memcpy((dst),(src),sizeof((dst)[0])*(count)))
 
 #endif /* secnet_h */