diff options
| author | Ed Swierk <eswierk@aristanetworks.com> | 2009-08-20 19:00:31 -0700 |
|---|---|---|
| committer | Anthony Liguori <aliguori@us.ibm.com> | 2009-08-27 20:46:58 -0500 |
| commit | df7a86ed735eafefbd046c8cad7134652fe3f600 (patch) | |
| tree | 585563918d17462f707cebdae337d5fcde45d927 /slirp/ip_icmp.c | |
| parent | ce0bd027df9c62766a5417521d0f08f27359d43f (diff) | |
slirp: Read host DNS config on demand
Currently the qemu user-mode networking stack reads the host DNS
configuration (/etc/resolv.conf or the Windows equivalent) only once
when qemu starts. This causes name lookups in the guest to fail if the
host is moved to a different network from which the original DNS servers
are unreachable, a common occurrence when the host is a laptop.
This patch changes the slirp code to read the host DNS configuration on
demand, caching the results for at most 1 second to avoid unnecessary
overhead if name lookups occur in rapid succession. On non-Windows
hosts, /etc/resolv.conf is re-read only if the file has been replaced or
if its size or mtime has changed.
Signed-off-by: Ed Swierk <eswierk@aristanetworks.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Diffstat (limited to 'slirp/ip_icmp.c')
| -rw-r--r-- | slirp/ip_icmp.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/slirp/ip_icmp.c b/slirp/ip_icmp.c index 95a4b39a4e..751a8e249a 100644 --- a/slirp/ip_icmp.c +++ b/slirp/ip_icmp.c @@ -127,7 +127,8 @@ icmp_input(struct mbuf *m, int hlen) slirp->vnetwork_addr.s_addr) { /* It's an alias */ if (so->so_faddr.s_addr == slirp->vnameserver_addr.s_addr) { - addr.sin_addr = dns_addr; + if (get_dns_addr(&addr.sin_addr) < 0) + addr.sin_addr = loopback_addr; } else { addr.sin_addr = loopback_addr; } |