In article <[EMAIL PROTECTED]>,
Martin Burnicki <[EMAIL PROTECTED]> wrote:
>AFAIK ntpd has to manage the binding to interfaces at least if autokey is
>enabled since the signature hash also includes the IP address of the
>interface via which a packet is sent.
At least some operating systems (don't know about Linux) allow this to
be controlled using a control message. For example, from the FreeBSD
6.3 ip(4) manual page:
The source address to be used for outgoing UDP datagrams on a socket that
is not bound to a specific IP address can be specified as ancillary data
with a type code of IP_SENDSRCADDR. The msg_control field in the msghdr
structure should point to a buffer that contains a cmsghdr structure fol-
lowed by the IP address. The cmsghdr fields should have the following
values:
cmsg_len = sizeof(struct in_addr)
cmsg_level = IPPROTO_IP
cmsg_type = IP_SENDSRCADDR
For convenience, IP_SENDSRCADDR is defined to have the same value as
IP_RECVDSTADDR, so the IP_RECVDSTADDR control message from recvmsg(2) can
be used directly as a control message for sendmsg(2).
The IPV6_PKTINFO message is used for analogous functions in IPv6.
-GAWollman
--
Garrett A. Wollman | The real tragedy of human existence is not that we are
[EMAIL PROTECTED]| nasty by nature, but that a cruel structural asymmetry
Opinions not those | grants to rare events of meanness such power to shape
of MIT or CSAIL. | our history. - S.J. Gould, Ten Thousand Acts of Kindness
_______________________________________________
questions mailing list
[email protected]
https://lists.ntp.org/mailman/listinfo/questions
