From 7aa16180508db5b9d9e29d65273d975b3d5db7ad Mon Sep 17 00:00:00 2001 From: tmarkwalder Date: Wed, 3 May 2017 10:06:22 -0400 Subject: [v4_3] dhclient can now enforce require options statement in -6 mode Merges in rt41473. --- RELNOTES | 7 +++++++ client/dhc6.c | 14 ++++++++++++-- client/dhclient.conf.5 | 5 +++++ includes/site.h | 7 +++++++ 4 files changed, 31 insertions(+), 2 deletions(-) diff --git a/RELNOTES b/RELNOTES index 8aaa5891..8272e2a5 100644 --- a/RELNOTES +++ b/RELNOTES @@ -114,6 +114,13 @@ by Eric Young (eay@cryptsoft.com). BlueCat Networks for bringing the matter to our attention. [ISC-Bugs #43592] +- When running in -6 mode, dhclient can enforce the require option statement + and will discard offered leases that do not contain all the required + options specified in the client configuration. If not enabled the client + will still consider such leases. This must be enabled at compile time + (see ENFORCE_DHCPV6_CLIENT_REQUIRE in includes/site.h). + [ISC-Bugs #41473] + Changes since 4.3.5b1 - Corrected a bug which could cause the server to sporadically crash while diff --git a/client/dhc6.c b/client/dhc6.c index c8d16e8a..450afe5f 100644 --- a/client/dhc6.c +++ b/client/dhc6.c @@ -141,6 +141,8 @@ static isc_result_t dhc6_check_status(isc_result_t rval, struct option_state *options, const char *scope, unsigned *code); +static int dhc6_score_lease(struct client_state *client, + struct dhc6_lease *lease); extern int onetry; extern int stateless; @@ -3133,6 +3135,15 @@ init_handler(struct packet *packet, struct client_state *client) return; } + int lease_score = dhc6_score_lease(client, lease); +#ifdef ENFORCE_DHCPV6_CLIENT_REQUIRE + if (lease_score == 0) { + log_debug("RCV:Advertised lease scored 0, toss it."); + dhc6_lease_destroy(&lease, MDL); + return; + } +#endif + insert_lease(&client->advertised_leases, lease); /* According to RFC3315 section 17.1.2, the client MUST wait for @@ -3146,8 +3157,7 @@ init_handler(struct packet *packet, struct client_state *client) * should not if the advertise contains less than one IA and address. */ if ((client->txcount > 1) || - ((lease->pref == 255) && - (dhc6_score_lease(client, lease) > SCORE_MIN))) { + ((lease->pref == 255) && (lease_score > SCORE_MIN))) { log_debug("RCV: Advertisement immediately selected."); cancel_timeout(do_init6, client); start_selecting6(client); diff --git a/client/dhclient.conf.5 b/client/dhclient.conf.5 index d0ff1145..966970bd 100644 --- a/client/dhclient.conf.5 +++ b/client/dhclient.conf.5 @@ -266,6 +266,11 @@ options will be ignored. There is no default require list. also require domain-search; } .fi + +NOTE: For ISC DHCP release 4.3.5 and earlier, dhclient running in -6 mode does +not discard offers as described above. This has been corrected as of release +4.3.6 but must be enabled at compile time (see ENFORCE_DHCPV6_CLIENT_REQUIRE +in includes/site.h). .PP .I The .B send diff --git a/includes/site.h b/includes/site.h index 1f4407f4..4a2166cc 100644 --- a/includes/site.h +++ b/includes/site.h @@ -318,6 +318,13 @@ allow at one time. A value of 0 means there is no limit.*/ #define MAX_FD_VALUE 200 +/* Enable enforcement of the require option statement as documented + * in man page. Instructs the dhclient, when in -6 mode, to discard + * offered leases that do not contain all options specified as required + * in the client's configuration file. The client already enforces this + * in -4 mode. */ +/* #define ENFORCE_DHCPV6_CLIENT_REQUIRE */ + /* Include definitions for various options. In general these should be left as is, but if you have already defined one of these and prefer your definition you can comment the -- cgit v1.2.1