sockets: add ability to disable DNS resolution for InetSocketAddress

Add a 'numeric' flag to the InetSocketAddress struct to allow the
caller to indicate that DNS should be skipped for the host/port
fields. This is useful if the caller knows the address is already
numeric and wants to guarantee no (potentially blocking) DNS
lookups are attempted.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
This commit is contained in:
Daniel P. Berrange 2016-07-19 12:58:52 +01:00
parent 598cf1c805
commit 6979a813f3
2 changed files with 12 additions and 0 deletions

View file

@ -3983,6 +3983,10 @@
#
# @port: port part of the address, or lowest port if @to is present
#
# @numeric: #optional true if the host/port are guaranteed to be numeric,
# false if name resolution should be attempted. Defaults to false.
# (Since 2.9)
#
# @to: highest port to try
#
# @ipv4: whether to accept IPv4 addresses, default try both IPv4 and IPv6
@ -3997,6 +4001,7 @@
'data': {
'host': 'str',
'port': 'str',
'*numeric': 'bool',
'*to': 'uint16',
'*ipv4': 'bool',
'*ipv6': 'bool' } }

View file

@ -38,6 +38,10 @@
# define AI_V4MAPPED 0
#endif
#ifndef AI_NUMERICSERV
# define AI_NUMERICSERV 0
#endif
static int inet_getport(struct addrinfo *e)
{
@ -141,6 +145,9 @@ static int inet_listen_saddr(InetSocketAddress *saddr,
memset(&ai,0, sizeof(ai));
ai.ai_flags = AI_PASSIVE;
if (saddr->has_numeric && saddr->numeric) {
ai.ai_flags |= AI_NUMERICHOST | AI_NUMERICSERV;
}
ai.ai_family = inet_ai_family_from_address(saddr, &err);
ai.ai_socktype = SOCK_STREAM;