From 861f1da0731bf29dcb9221c4f22c76b40ec15a78 Mon Sep 17 00:00:00 2001 From: NIIBE Yutaka Date: Wed, 20 Jun 2018 08:59:05 +0900 Subject: [PATCH] libdns: Let kernel to decide the local port. * dirmngr/dns.c (LEAVE_SELECTION_OF_PORT_TO_KERNEL): New. (dns_socket): Don't select ephemeral port in user space. -- There is no good reason to bind local port aggressively. It might be some reason to do so, then, a user can specify it in /etc/resolv.conf by the second argument of "interface" directive. At least, it causes a problem on Windows. Binding a specified port in user space can trigger the Firewall dialog on Windows. Since it can be considered valid question, it is better not to bind with an ephemeral port which is selected in user space, by default. GnuPG-bug-id: 3610 Signed-off-by: NIIBE Yutaka --- dirmngr/dns.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/dirmngr/dns.c b/dirmngr/dns.c index 908bf157a..f82ed26cf 100644 --- a/dirmngr/dns.c +++ b/dirmngr/dns.c @@ -7121,6 +7121,8 @@ static int dns_socket(struct sockaddr *local, int type, int *error_) { if (type != SOCK_DGRAM) return fd; +#define LEAVE_SELECTION_OF_PORT_TO_KERNEL +#if !defined(LEAVE_SELECTION_OF_PORT_TO_KERNEL) /* * FreeBSD, Linux, OpenBSD, OS X, and Solaris use random ports by * default. Though the ephemeral range is quite small on OS X @@ -7146,6 +7148,7 @@ static int dns_socket(struct sockaddr *local, int type, int *error_) { /* NB: continue to next bind statement */ } +#endif if (0 == bind(fd, local, dns_sa_len(local))) return fd;