Use AI_ADDRCONFIG for more efficient getaddrinfo

Add AI_ADDRCONFIG to the hint flags for every invocation of
getaddrinfo which wasn't already using it.  This is often the default
behavior when no hints are specified, but we tend to specify hints a
lot, so we have to say it ourselves.  AI_ADDRCONFIG causes AAAA
lookups to be skipped if the system has no public IPv6 interface
addresses, usually saving a couple of DNS queries per getaddrinfo
call and allowing DNS caching to be much more effective without the
need for negative caching.

ticket: 6923

git-svn-id: svn://anonsvn.mit.edu/krb5/trunk@24978 dc483132-0cff-0310-8789-dd5450dbe970

9 files changed, 11 insertions, 6 deletions

diff --git a/src/appl/sample/sclient/sclient.c b/src/appl/sample/sclient/sclient.c
index eb868d2d2f..7ec8edd0e6 100644
--- a/src/appl/sample/sclient/sclient.c
+++ b/src/appl/sample/sclient/sclient.c
@@ -125,6 +125,7 @@ main(int argc, char *argv[])
 
     memset(&aihints, 0, sizeof(aihints));
     aihints.ai_socktype = SOCK_STREAM;
+    aihints.ai_flags = AI_ADDRCONFIG;
     aierr = getaddrinfo(argv[1], portstr, &aihints, &ap);
     if (aierr) {
         fprintf(stderr, "%s: error looking up host '%s' port '%s'/tcp: %s\n",
diff --git a/src/kadmin/dbutil/kadm5_create.c b/src/kadmin/dbutil/kadm5_create.c
index 65cd68be5d..9d5ee1da4e 100644
--- a/src/kadmin/dbutil/kadm5_create.c
+++ b/src/kadmin/dbutil/kadm5_create.c
@@ -184,7 +184,7 @@ static int add_admin_princs(void *handle, krb5_context context, char *realm)
         goto clean_and_exit;
     }
     memset(&ai_hints, 0, sizeof(ai_hints));
-    ai_hints.ai_flags = AI_CANONNAME;
+    ai_hints.ai_flags = AI_CANONNAME | AI_ADDRCONFIG;
     gai_error = getaddrinfo(localname, (char *)NULL, &ai_hints, &ai);
     if (gai_error) {
         ret = EINVAL;
diff --git a/src/lib/kadm5/alt_prof.c b/src/lib/kadm5/alt_prof.c
index 98231ab330..6537d30257 100644
--- a/src/lib/kadm5/alt_prof.c
+++ b/src/lib/kadm5/alt_prof.c
@@ -897,7 +897,7 @@ kadm5_get_admin_service_name(krb5_context ctx,
     }
 
     memset(&hint, 0, sizeof(hint));
-    hint.ai_flags = AI_CANONNAME;
+    hint.ai_flags = AI_CANONNAME | AI_ADDRCONFIG;
     err = getaddrinfo(params_out.admin_server, NULL, &hint, &ai);
     if (err != 0) {
         ret = KADM5_CANT_RESOLVE;
diff --git a/src/lib/kadm5/clnt/client_init.c b/src/lib/kadm5/clnt/client_init.c
index 735ddfd317..d6309979ff 100644
--- a/src/lib/kadm5/clnt/client_init.c
+++ b/src/lib/kadm5/clnt/client_init.c
@@ -563,8 +563,9 @@ connect_to_server(const char *hostname, int port, int *fd)
     (void) snprintf(portbuf, sizeof(portbuf), "%d", port);
     memset(&hint, 0, sizeof(hint));
     hint.ai_socktype = SOCK_STREAM;
+    hint.ai_flags = AI_ADDRCONFIG;
 #ifdef AI_NUMERICSERV
-    hint.ai_flags = AI_NUMERICSERV;
+    hint.ai_flags |= AI_NUMERICSERV;
 #endif
     err = getaddrinfo(hostname, portbuf, &hint, &addrs);
     if (err != 0)
diff --git a/src/lib/krb5/os/hostaddr.c b/src/lib/krb5/os/hostaddr.c
index ccab1d0e4a..5046f9b318 100644
--- a/src/lib/krb5/os/hostaddr.c
+++ b/src/lib/krb5/os/hostaddr.c
@@ -41,7 +41,7 @@ krb5_os_hostaddr(krb5_context context, const char *name,
         return KRB5_ERR_BAD_HOSTNAME;
 
     memset (&hints, 0, sizeof (hints));
-    hints.ai_flags = AI_NUMERICHOST;
+    hints.ai_flags = AI_NUMERICHOST | AI_ADDRCONFIG;
     /* We don't care what kind at this point, really, but without
        this, we can get back multiple sockaddrs per address, for
        SOCK_DGRAM, SOCK_STREAM, and SOCK_RAW.  I haven't checked if
diff --git a/src/lib/krb5/os/hst_realm.c b/src/lib/krb5/os/hst_realm.c
index 33e13e1c59..d780433f8f 100644
--- a/src/lib/krb5/os/hst_realm.c
+++ b/src/lib/krb5/os/hst_realm.c
@@ -107,7 +107,7 @@ get_fq_hostname(char *buf, size_t bufsize, const char *name)
     int err;
 
     memset (&hints, 0, sizeof (hints));
-    hints.ai_flags = AI_CANONNAME;
+    hints.ai_flags = AI_CANONNAME | AI_ADDRCONFIG;
     err = getaddrinfo (name, 0, &hints, &ai);
     if (err)
         return krb5int_translate_gai_error (err);
diff --git a/src/lib/krb5/os/sendto_kdc.c b/src/lib/krb5/os/sendto_kdc.c
index a3eb322341..371af9d23f 100644
--- a/src/lib/krb5/os/sendto_kdc.c
+++ b/src/lib/krb5/os/sendto_kdc.c
@@ -725,8 +725,9 @@ resolve_server(krb5_context context, const struct serverlist *servers,
     memset(&hint, 0, sizeof(hint));
     hint.ai_family = entry->family;
     hint.ai_socktype = (entry->socktype != 0) ? entry->socktype : socktype1;
+    hint.ai_flags = AI_ADDRCONFIG;
 #ifdef AI_NUMERICSERV
-    hint.ai_flags = AI_NUMERICSERV;
+    hint.ai_flags |= AI_NUMERICSERV;
 #endif
     result = snprintf(portbuf, sizeof(portbuf), "%d", ntohs(entry->port));
     if (SNPRINTF_OVERFLOW(result, sizeof(portbuf)))
diff --git a/src/plugins/locate/python/py-locate.c b/src/plugins/locate/python/py-locate.c
index 23b407c633..7273026760 100644
--- a/src/plugins/locate/python/py-locate.c
+++ b/src/plugins/locate/python/py-locate.c
@@ -302,6 +302,7 @@ lookup(void *blob, enum locate_service_type svc, const char *realm,
             return -1;
         }
         aihints.ai_socktype = thissocktype;
+        aihints.ai_flags = AI_ADDRCONFIG;
         x = getaddrinfo (hoststr, portstr, &aihints, &airesult);
         if (x != 0)
             continue;
diff --git a/src/slave/kprop.c b/src/slave/kprop.c
index f1b676fb8a..1c2a93b175 100644
--- a/src/slave/kprop.c
+++ b/src/slave/kprop.c
@@ -322,6 +322,7 @@ open_connection(krb5_context context, char *host, int *fd)
     memset(&hints, 0, sizeof(hints));
     hints.ai_family = PF_UNSPEC;
     hints.ai_socktype = SOCK_STREAM;
+    hints.ai_flags = AI_ADDRCONFIG;
     error = getaddrinfo(host, port, &hints, &answers);
     if (error != 0) {
         com_err(progname, 0, "%s: %s", host, gai_strerror(error));