Implements default router preference (RFC 4191) for RAdv.

Thanks to Baptiste Jonglez for the patch.
This commit is contained in:
Ondrej Zajicek 2014-07-07 22:56:21 +02:00
parent 6285793f18
commit 751482899c
5 changed files with 30 additions and 6 deletions

View file

@ -3013,6 +3013,10 @@ definitions, prefix definitions and DNS definitions:
as a default router. For <cf/sensitive/ option, see <ref id="dsc-trigger" name="trigger">. as a default router. For <cf/sensitive/ option, see <ref id="dsc-trigger" name="trigger">.
Default: 3 * <cf/max ra interval/, <cf/sensitive/ yes. Default: 3 * <cf/max ra interval/, <cf/sensitive/ yes.
<tag>default preference low|medium|high</tag>
This option specifies the Default Router Preference value to advertise
to hosts. Default: medium.
<tag>rdnss local <m/switch/</tag> <tag>rdnss local <m/switch/</tag>
Use only local (interface-specific) RDNSS definitions for this Use only local (interface-specific) RDNSS definitions for this
interface. Otherwise, both global and local definitions are used. Could interface. Otherwise, both global and local definitions are used. Could

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@ -30,9 +30,9 @@ CF_KEYWORDS(RADV, PREFIX, INTERFACE, MIN, MAX, RA, DELAY, INTERVAL,
MANAGED, OTHER, CONFIG, LINK, MTU, REACHABLE, TIME, RETRANS, MANAGED, OTHER, CONFIG, LINK, MTU, REACHABLE, TIME, RETRANS,
TIMER, CURRENT, HOP, LIMIT, DEFAULT, VALID, PREFERRED, MULT, TIMER, CURRENT, HOP, LIMIT, DEFAULT, VALID, PREFERRED, MULT,
LIFETIME, SKIP, ONLINK, AUTONOMOUS, RDNSS, DNSSL, NS, DOMAIN, LIFETIME, SKIP, ONLINK, AUTONOMOUS, RDNSS, DNSSL, NS, DOMAIN,
LOCAL, TRIGGER, SENSITIVE) LOCAL, TRIGGER, SENSITIVE, PREFERENCE, LOW, MEDIUM, HIGH)
%type<i> radv_mult radv_sensitive %type<i> radv_mult radv_sensitive radv_preference
CF_GRAMMAR CF_GRAMMAR
@ -84,6 +84,7 @@ radv_iface_start:
RADV_IFACE->current_hop_limit = DEFAULT_CURRENT_HOP_LIMIT; RADV_IFACE->current_hop_limit = DEFAULT_CURRENT_HOP_LIMIT;
RADV_IFACE->default_lifetime = -1; RADV_IFACE->default_lifetime = -1;
RADV_IFACE->default_lifetime_sensitive = 1; RADV_IFACE->default_lifetime_sensitive = 1;
RADV_IFACE->default_preference = RA_PREF_MEDIUM;
}; };
radv_iface_item: radv_iface_item:
@ -101,6 +102,7 @@ radv_iface_item:
if (($3 < 0) || ($3 > 9000)) cf_error("Default lifetime must be in range 0-9000"); if (($3 < 0) || ($3 > 9000)) cf_error("Default lifetime must be in range 0-9000");
if ($4 != -1) RADV_IFACE->default_lifetime_sensitive = $4; if ($4 != -1) RADV_IFACE->default_lifetime_sensitive = $4;
} }
| DEFAULT PREFERENCE radv_preference { RADV_IFACE->default_preference = $3; }
| PREFIX radv_prefix { add_tail(&RADV_IFACE->pref_list, NODE this_radv_prefix); } | PREFIX radv_prefix { add_tail(&RADV_IFACE->pref_list, NODE this_radv_prefix); }
| RDNSS { init_list(&radv_dns_list); } radv_rdnss { add_tail_list(&RADV_IFACE->rdnss_list, &radv_dns_list); } | RDNSS { init_list(&radv_dns_list); } radv_rdnss { add_tail_list(&RADV_IFACE->rdnss_list, &radv_dns_list); }
| DNSSL { init_list(&radv_dns_list); } radv_dnssl { add_tail_list(&RADV_IFACE->dnssl_list, &radv_dns_list); } | DNSSL { init_list(&radv_dns_list); } radv_dnssl { add_tail_list(&RADV_IFACE->dnssl_list, &radv_dns_list); }
@ -108,6 +110,11 @@ radv_iface_item:
| DNSSL LOCAL bool { RADV_IFACE->dnssl_local = $3; } | DNSSL LOCAL bool { RADV_IFACE->dnssl_local = $3; }
; ;
radv_preference:
LOW { $$ = RA_PREF_LOW; }
| MEDIUM { $$ = RA_PREF_MEDIUM; }
| HIGH { $$ = RA_PREF_HIGH; }
radv_iface_finish: radv_iface_finish:
{ {
struct radv_iface_config *ic = RADV_IFACE; struct radv_iface_config *ic = RADV_IFACE;

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@ -251,10 +251,11 @@ radv_prepare_ra(struct radv_iface *ifa)
pkt->code = 0; pkt->code = 0;
pkt->checksum = 0; pkt->checksum = 0;
pkt->current_hop_limit = ic->current_hop_limit; pkt->current_hop_limit = ic->current_hop_limit;
pkt->flags = (ic->managed ? OPT_RA_MANAGED : 0) |
(ic->other_config ? OPT_RA_OTHER_CFG : 0);
pkt->router_lifetime = (ra->active || !ic->default_lifetime_sensitive) ? pkt->router_lifetime = (ra->active || !ic->default_lifetime_sensitive) ?
htons(ic->default_lifetime) : 0; htons(ic->default_lifetime) : 0;
pkt->flags = (ic->managed ? OPT_RA_MANAGED : 0) |
(ic->other_config ? OPT_RA_OTHER_CFG : 0) |
(pkt->router_lifetime ? ic->default_preference : 0);
pkt->reachable_time = htonl(ic->reachable_time); pkt->reachable_time = htonl(ic->reachable_time);
pkt->retrans_timer = htonl(ic->retrans_timer); pkt->retrans_timer = htonl(ic->retrans_timer);
buf += sizeof(*pkt); buf += sizeof(*pkt);
@ -330,10 +331,15 @@ radv_send_ra(struct radv_iface *ifa, int shutdown)
if (shutdown) if (shutdown)
{ {
/* Modify router lifetime to 0, it is not restored because /*
we suppose that the iface will be removed */ * Modify router lifetime to 0, it is not restored because we suppose that
* the iface will be removed. The preference value also has to be zeroed.
* (RFC 4191 2.2: If router lifetime is 0, the preference value must be 0.)
*/
struct radv_ra_packet *pkt = (void *) ifa->sk->tbuf; struct radv_ra_packet *pkt = (void *) ifa->sk->tbuf;
pkt->router_lifetime = 0; pkt->router_lifetime = 0;
pkt->flags &= ~RA_PREF_MASK;
} }
RADV_TRACE(D_PACKETS, "Sending RA via %s", ifa->iface->name); RADV_TRACE(D_PACKETS, "Sending RA via %s", ifa->iface->name);

View file

@ -40,6 +40,7 @@
* Supported standards: * Supported standards:
* - RFC 4861 - main RA standard * - RFC 4861 - main RA standard
* - RFC 6106 - DNS extensions (RDDNS, DNSSL) * - RFC 6106 - DNS extensions (RDDNS, DNSSL)
* - RFC 4191 (partial) - Default Router Preference
*/ */
static void static void

View file

@ -80,6 +80,7 @@ struct radv_iface_config
u32 current_hop_limit; u32 current_hop_limit;
u32 default_lifetime; u32 default_lifetime;
u8 default_lifetime_sensitive; /* Whether default_lifetime depends on trigger */ u8 default_lifetime_sensitive; /* Whether default_lifetime depends on trigger */
u8 default_preference; /* Default Router Preference (RFC 4191) */
}; };
struct radv_prefix_config struct radv_prefix_config
@ -144,6 +145,11 @@ struct radv_iface
#define RA_EV_CHANGE 2 /* Change of options or prefixes */ #define RA_EV_CHANGE 2 /* Change of options or prefixes */
#define RA_EV_RS 3 /* Received RS */ #define RA_EV_RS 3 /* Received RS */
/* Default Router Preferences (RFC 4191) */
#define RA_PREF_LOW 0x18
#define RA_PREF_MEDIUM 0x00
#define RA_PREF_HIGH 0x08
#define RA_PREF_MASK 0x18
#ifdef LOCAL_DEBUG #ifdef LOCAL_DEBUG