diff options
| author | Reyk Floeter <reyk@cvs.openbsd.org> | 2015-02-10 06:40:09 +0000 |
|---|---|---|
| committer | Reyk Floeter <reyk@cvs.openbsd.org> | 2015-02-10 06:40:09 +0000 |
| commit | 30d20b716e66b1f85838cb182cf559a5dbb74f8d (patch) | |
| tree | 7f5ff89475eaf36c7543b26cd2df180930ed47cc /usr.sbin/ntpd/config.c | |
| parent | f1fa0ce413d09843226a5aecc06902194ce48d33 (diff) | |
Add support for "constraints": when configured, ntpd(8) will query the
time from HTTPS servers, by parsing the Date: header, and use the
median constraint time as a boundary to verify NTP responses. This
adds some level of authentication and protection against MITM attacks
while preserving the accuracy of the NTP protocol; without relying on
authentication options for NTP that are basically unavailable at
present. This is an initial implementation and the semantics will be
improved once it is in the tree.
Discussed with deraadt@ and henning@
OK henning@
Diffstat (limited to 'usr.sbin/ntpd/config.c')
| -rw-r--r-- | usr.sbin/ntpd/config.c | 16 |
1 files changed, 15 insertions, 1 deletions
diff --git a/usr.sbin/ntpd/config.c b/usr.sbin/ntpd/config.c index e2443e65445..35d7b31f742 100644 --- a/usr.sbin/ntpd/config.c +++ b/usr.sbin/ntpd/config.c @@ -1,4 +1,4 @@ -/* $OpenBSD: config.c,v 1.25 2015/02/08 04:54:15 reyk Exp $ */ +/* $OpenBSD: config.c,v 1.26 2015/02/10 06:40:08 reyk Exp $ */ /* * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org> @@ -33,6 +33,7 @@ struct ntp_addr *host_v4(const char *); struct ntp_addr *host_v6(const char *); static u_int32_t maxid = 0; +static u_int32_t constraint_maxid = 0; void host(const char *s, struct ntp_addr **hn) @@ -193,3 +194,16 @@ new_sensor(char *device) return (s); } + +struct constraint * +new_constraint(void) +{ + struct constraint *p; + + if ((p = calloc(1, sizeof(struct constraint))) == NULL) + fatal("new_constraint calloc"); + p->id = ++constraint_maxid; + + return (p); +} + |