krb5 commit: Add a family-independent bindresvport_sa function

[Greg Hudson]

https://github.com/krb5/krb5/commit/0d04b60d159ab83b943e43802b1449a3b074bc83
commit 0d04b60d159ab83b943e43802b1449a3b074bc83
Author: Andreas Schneider <asn at samba.org>
Date:   Tue May 27 19:47:22 2014 +0200

    Add a family-independent bindresvport_sa function
    
    This functions allows you to pass IPv4 and IPv6 addresses.  If no
    address is given, t will determine the family by checking the socket
    with getsockname.
    
    [ghudson at mit.edu: clarified commit message, split out setport helper,
    squashed with next commit, minimized code changes from old
    bindresvport, used socket-utils.h helpers]
    
    ticket: 7935 (new)

 src/include/gssrpc/rename.h |    1 +
 src/include/gssrpc/rpc.h    |    1 +
 src/lib/rpc/bindresvport.c  |   34 +++++++++++++++++++++++-----------
 3 files changed, 25 insertions(+), 11 deletions(-)

diff --git a/src/include/gssrpc/rename.h b/src/include/gssrpc/rename.h
index ecec66a..444bc97 100644
--- a/src/include/gssrpc/rename.h
+++ b/src/include/gssrpc/rename.h
@@ -177,6 +177,7 @@
 
 #define get_myaddress		gssrpc_get_myaddress
 #define bindresvport		gssrpc_bindresvport
+#define bindresvport_sa		gssrpc_bindresvport_sa
 #define callrpc			gssrpc_callrpc
 #define getrpcport		gssrpc_getrpcport
 
diff --git a/src/include/gssrpc/rpc.h b/src/include/gssrpc/rpc.h
index 565f1c2..2d94a7f 100644
--- a/src/include/gssrpc/rpc.h
+++ b/src/include/gssrpc/rpc.h
@@ -92,6 +92,7 @@
 GSSRPC__BEGIN_DECLS
 extern int get_myaddress(struct sockaddr_in *);
 extern int bindresvport(int, struct sockaddr_in *);
+extern int bindresvport_sa(int, struct sockaddr *);
 extern int callrpc(char *, rpcprog_t, rpcvers_t, rpcproc_t, xdrproc_t,
 		   char *, xdrproc_t , char *);
 extern int getrpcport(char *, rpcprog_t, rpcvers_t, rpcprot_t);
diff --git a/src/lib/rpc/bindresvport.c b/src/lib/rpc/bindresvport.c
index 6755f4d..fa28b60 100644
--- a/src/lib/rpc/bindresvport.c
+++ b/src/lib/rpc/bindresvport.c
@@ -1,6 +1,7 @@
 /* lib/rpc/bindresvport.c */
 /*
  * Copyright (c) 2010, Oracle America, Inc.
+ * Copyright (c) 2014, Andreas Schneider <asn at samba.org>
  *
  * All rights reserved.
  *
@@ -33,6 +34,8 @@
  */
 
 #include <string.h>
+#include <stdlib.h>
+#include <stdint.h>
 #include <unistd.h>
 #include <sys/types.h>
 #include <sys/errno.h>
@@ -40,27 +43,31 @@
 #include <netinet/in.h>
 #include <gssrpc/rpc.h>
 #include <errno.h>
+#include "socket-utils.h"
 
 /*
  * Bind a socket to a privileged IP port
  */
 int
-bindresvport(int sd, struct sockaddr_in *sockin)
+bindresvport_sa(int sd, struct sockaddr *sa)
 {
 	int res;
 	static short port;
-	struct sockaddr_in myaddr;
+	struct sockaddr_storage myaddr;
+	socklen_t salen;
 	int i;
 
 #define STARTPORT 600
 #define ENDPORT (IPPORT_RESERVED - 1)
 #define NPORTS	(ENDPORT - STARTPORT + 1)
-
-	if (sockin == (struct sockaddr_in *)0) {
-		sockin = &myaddr;
-		memset(sockin, 0, sizeof (*sockin));
-		sockin->sin_family = AF_INET;
-	} else if (sockin->sin_family != AF_INET) {
+	if (sa == NULL) {
+		salen = sizeof(myaddr);
+		sa = ss2sa(&myaddr);
+		res = getsockname(sd, sa, &salen);
+		if (res < 0)
+			return (-1);
+	}
+	if (!sa_is_inet(sa)) {
 		errno = EPFNOSUPPORT;
 		return (-1);
 	}
@@ -70,12 +77,17 @@ bindresvport(int sd, struct sockaddr_in *sockin)
 	res = -1;
 	errno = EADDRINUSE;
 	for (i = 0; i < NPORTS && res < 0 && errno == EADDRINUSE; i++) {
-		sockin->sin_port = htons(port++);
+		sa_setport(sa, htons(port++));
 		if (port > ENDPORT) {
 			port = STARTPORT;
 		}
-		res = bind(sd, (struct sockaddr *) sockin,
-			   sizeof(struct sockaddr_in));
+		res = bind(sd, sa, socklen(sa));
 	}
 	return (res);
 }
+
+int
+bindresvport(int sd, struct sockaddr_in *sockin)
+{
+	return (bindresvport_sa(sd, (struct sockaddr *)sockin));
+}