[Olsr-dev] [PATCH v1 1/1] lq_packet: only report a neighbour once in a hello message
Ferry Huberts
(spam-protected)
Mon Jan 16 18:14:42 CET 2017
I think I may have stumbled onto a MUCH easier fix to this problem.
The actual problem is quite involved (with fragmented hello messages etc) but it all boils down to a later UNSPEC link overwriting a previous SYM/ASYM/other link on the receiving end.
Since the neighbours in a hello message are already ordered when the hello message is sent out, the following patch also solves it.
Opinions?
diff --git a/src/lq_packet.c b/src/lq_packet.c
index d44e654..287f4b4 100644
--- a/src/lq_packet.c
+++ b/src/lq_packet.c
@@ -326,7 +326,7 @@ serialize_common(struct olsr_common *comm)
static void
serialize_lq_hello(struct lq_hello_message *lq_hello, struct interface_olsr *outif)
{
- static const int LINK_ORDER[] = { SYM_LINK, UNSPEC_LINK, ASYM_LINK, LOST_LINK };
+ static const int LINK_ORDER[] = { UNSPEC_LINK, LOST_LINK, ASYM_LINK, SYM_LINK };
int rem, size, req, expected_size = 0;
struct lq_hello_info_header *info_head;
struct lq_hello_neighbor *neigh;
On 13/01/17 09:05, Ferry Huberts wrote:
> From: "Iwan G. Flameling" <(spam-protected)>
>
> A while ago we noticed that neighbours of nodes with multiple interfaces
> on the same medium report infinite costs on their links to those nodes.
>
> This problem is 100% reproducible.
>
> Below is the setup in which we noticed the problem.
>
> wlan0 wlan0
> 172.31.175.97/16 172.31.175.61/16
> (((*))) ------------------------------------------------- (((*)))
> | |
> | |
> | |
> ____|___ 172.29.175.97/15 ________ 172.29.175.61/15 ____|____
> | |-eth1.2580---------| |--------eth1.2580-| |
> | Node 97 | | Switch | | Node 61 |
> |_________|-eth2.2580---------|________| |_________|
> 172.28.175.97/15
>
> In this setup node 97 will report normal link costs for its (wired) links
> to node 61 (see the first table below), while node 61 will report infinite
> link costs for both its (wired) links to node 97 (see the second table
> below).
>
> Table: Links (node 97)
> Local IP Remote IP Hyst. LQ NLQ Cost
> 172.29.175.97 172.29.175.61 0.000 1.000 1.000 0.100
> 172.28.175.97 172.29.175.61 0.000 1.000 1.000 0.100
> 172.31.175.97 172.31.175.61 0.000 1.000 1.000 1.000
>
> Table: Links (node 61)
> Local IP Remote IP Hyst. LQ NLQ Cost
> 172.29.175.61 172.29.175.97 0.000 1.000 0.000 INFINITE
> 172.29.175.61 172.28.175.97 0.000 1.000 0.000 INFINITE
> 172.31.175.61 172.31.175.97 0.000 1.000 1.000 1.000
>
> Checking the HELLO messages that are received on node 61 from node 97,
> we see the following:
>
> [node 61] # tcpdump -vni eth1.2580 udp port 698
> tcpdump: listening on eth1.2580, link-type EN10MB (Ethernet), capture size 262144 bytes
> 06:21:23.528204 IP (tos 0xc0, ttl 1, id 42455, offset 0, flags [DF], proto UDP (17), length 80)
> 172.28.175.97.698 > 255.255.255.255.698: OLSRv4, seq 0xf7c0, length 52
> Hello-LQ Message (0xc9), originator 172.31.175.97, ttl 1, hop 0
> vtime 3.000s, msg-seq 0x533d, length 48
> hello-time 1.000s, MPR willingness 3
> link-type Symmetric, neighbor-type Symmetric, len 12
> neighbor 172.29.175.61, link-quality 0.00%, neighbor-link-quality 0.00%
> link-type Unspecified, neighbor-type Symmetric, len 20
> neighbor 172.31.175.61, link-quality 0.00%, neighbor-link-quality 0.00%
> neighbor 172.29.175.61, link-quality 0.00%, neighbor-link-quality 0.00%
>
> Node 61 receives HELLO messages from node 97 that report (amongst others):
> 1- a SYMMETRIC link-type to node 61 (172.29.175.61)
> 2- an UNSPECIFIED link-type to node 61 (172.29.175.61)
>
> Clearly, this is 'confusing' and the root cause of why node 61 reports
> infinite costs for the links, as shown above.
>
> We pose that in a HELLO message the same neighbour should NEVER be
> reported with conflicting information.
>
> Proposed solution:
>
> 1- NEVER report a neighbour more than once in a HELLO message
> 2- Use the 'best' values for a neighbour that is reported in a HELLO
> message
>
> This requires:
>
> 1- De-duplication of neighbours when constructing a HELLO message.
>
> 2- When a neighbour is already present in the HELLO message
> that is under construction then he 'best' values must be determined
> and those in the neighbour that is already present should only be
> overwritten if those are worse.
>
> This patch implements that solution.
>
> Signed-off-by: Iwan G. Flameling <(spam-protected)>
> Signed-off-by: Ferry Huberts <(spam-protected)>
> ---
> src/lq_packet.c | 52 ++++++++++++----
> src/lq_plugin.c | 5 +-
> src/lq_plugin.h | 4 +-
> src/lq_plugin_default_ff.c | 13 +++-
> src/lq_plugin_default_ffeth.c | 13 +++-
> src/lq_plugin_default_float.c | 19 +++++-
> src/lq_plugin_default_fpm.c | 19 +++++-
> src/olsr_protocol.h | 136 ++++++++++++++++++++++++++++++++++++++++++
> 8 files changed, 236 insertions(+), 25 deletions(-)
>
> diff --git a/src/lq_packet.c b/src/lq_packet.c
> index d44e654..2e8e027 100644
> --- a/src/lq_packet.c
> +++ b/src/lq_packet.c
> @@ -68,6 +68,21 @@ bool lq_tc_pending = false;
> static uint32_t msg_buffer_aligned[(MAXMESSAGESIZE - OLSR_HEADERSIZE) / sizeof(uint32_t) + 1];
> static unsigned char *const msg_buffer = (unsigned char *)msg_buffer_aligned;
>
> +static struct lq_hello_neighbor * neigh_find(struct link_entry *link, struct lq_hello_message *lq_hello) {
> + struct lq_hello_neighbor *neigh;
> +
> + assert(link);
> + assert(lq_hello);
> +
> + for (neigh = lq_hello->neigh; neigh; neigh = neigh->next) {
> + if (ipequal(&link->neighbor_iface_addr, &neigh->addr)) {
> + return neigh;
> + }
> + }
> +
> + return NULL ;
> +}
> +
> static void
> create_lq_hello(struct lq_hello_message *lq_hello, struct interface_olsr *outif)
> {
> @@ -92,46 +107,57 @@ create_lq_hello(struct lq_hello_message *lq_hello, struct interface_olsr *outif)
> // loop through the link set
>
> OLSR_FOR_ALL_LINK_ENTRIES(walker) {
> + uint8_t link_type;
> + uint8_t neigh_type;
>
> // allocate a neighbour entry
> - struct lq_hello_neighbor *neigh = olsr_malloc_lq_hello_neighbor("Build LQ_HELLO");
> + struct lq_hello_neighbor *neigh = neigh_find(walker, lq_hello);
> + bool neigh_is_new = (neigh == NULL );
> + neigh = neigh_is_new ? olsr_malloc_lq_hello_neighbor("Build LQ_HELLO") : neigh;
>
> // a) this neighbor interface IS NOT visible via the output interface
> if (!ipequal(&walker->local_iface_addr, &outif->ip_addr))
> - neigh->link_type = UNSPEC_LINK;
> + link_type = UNSPEC_LINK;
>
> // b) this neighbor interface IS visible via the output interface
>
> else
> - neigh->link_type = lookup_link_status(walker);
> + link_type = lookup_link_status(walker);
> +
> + if (neigh_is_new || link_type_compare(neigh->link_type, link_type))
> + neigh->link_type = link_type;
>
> // set the entry's link quality
> - olsr_copy_hello_lq(neigh, walker);
> + olsr_copy_hello_lq(neigh, walker, neigh_is_new);
>
> // set the entry's neighbour type
>
> if (walker->neighbor->is_mpr)
> - neigh->neigh_type = MPR_NEIGH;
> + neigh_type = MPR_NEIGH;
>
> else if (walker->neighbor->status == SYM)
> - neigh->neigh_type = SYM_NEIGH;
> + neigh_type = SYM_NEIGH;
>
> else if (walker->neighbor->status == NOT_SYM)
> - neigh->neigh_type = NOT_NEIGH;
> + neigh_type = NOT_NEIGH;
>
> else {
> OLSR_PRINTF(0, "Error: neigh_type undefined");
> - neigh->neigh_type = NOT_NEIGH;
> + neigh_type = NOT_NEIGH;
> }
>
> - // set the entry's neighbour interface address
> + if (neigh_is_new || neigh_type_compare(neigh->neigh_type, neigh_type))
> + neigh->neigh_type = neigh_type;
>
> - neigh->addr = walker->neighbor_iface_addr;
> + if (neigh_is_new) {
> + // set the entry's neighbour interface address
>
> - // queue the neighbour entry
> - neigh->next = lq_hello->neigh;
> - lq_hello->neigh = neigh;
> + neigh->addr = walker->neighbor_iface_addr;
>
> + // queue the neighbour entry
> + neigh->next = lq_hello->neigh;
> + lq_hello->neigh = neigh;
> + }
> }
> OLSR_FOR_ALL_LINK_ENTRIES_END(walker);
> }
> diff --git a/src/lq_plugin.c b/src/lq_plugin.c
> index a917c84..01c6e4e 100644
> --- a/src/lq_plugin.c
> +++ b/src/lq_plugin.c
> @@ -351,13 +351,14 @@ get_linkcost_scaled(olsr_linkcost cost, bool route)
> *
> * @param target pointer to target lq_hello_neighbor
> * @param source pointer to source link_entry
> + * @param force true to force the copy, otherwise only copy when source is 'better' than target
> */
> void
> -olsr_copy_hello_lq(struct lq_hello_neighbor *target, struct link_entry *source)
> +olsr_copy_hello_lq(struct lq_hello_neighbor *target, struct link_entry *source, bool force)
> {
> assert((const char *)target + sizeof(*target) >= (const char *)target->linkquality);
> assert((const char *)source + sizeof(*source) >= (const char *)source->linkquality);
> - active_lq_handler->copy_link_lq_into_neigh(target->linkquality, source->linkquality);
> + active_lq_handler->copy_link_lq_into_neigh(target->linkquality, source->linkquality, force);
> }
>
> /**
> diff --git a/src/lq_plugin.h b/src/lq_plugin.h
> index 747a70c..26baba4 100644
> --- a/src/lq_plugin.h
> +++ b/src/lq_plugin.h
> @@ -76,7 +76,7 @@ struct lq_handler {
> void (*packet_loss_handler) (struct link_entry * entry, void *lq, bool lost);
>
> void (*memorize_foreign_hello) (void *local, void *foreign);
> - void (*copy_link_lq_into_neigh) (void *target, void *source);
> + void (*copy_link_lq_into_neigh) (void *target, void *source, bool force);
> void (*copy_link_lq_into_tc) (void *target, void *source);
> void (*clear_hello) (void *target);
> void (*clear_tc) (void *target);
> @@ -134,7 +134,7 @@ const char *get_linkcost_text(olsr_linkcost cost, bool route, struct lqtextbuffe
> double get_linkcost_scaled(olsr_linkcost cost, bool route);
>
> void olsr_clear_hello_lq(struct link_entry */*link*/);
> -void olsr_copy_hello_lq(struct lq_hello_neighbor *target, struct link_entry *source);
> +void olsr_copy_hello_lq(struct lq_hello_neighbor *target, struct link_entry *source, bool force);
> void olsr_copylq_link_entry_2_tc_mpr_addr(struct tc_mpr_addr *target, struct link_entry *source);
> void olsr_copylq_link_entry_2_tc_edge_entry(struct tc_edge_entry *target, struct link_entry *source);
> void olsr_clear_tc_lq(struct tc_mpr_addr *target);
> diff --git a/src/lq_plugin_default_ff.c b/src/lq_plugin_default_ff.c
> index 3d6ba6a..fa617e3 100644
> --- a/src/lq_plugin_default_ff.c
> +++ b/src/lq_plugin_default_ff.c
> @@ -70,7 +70,7 @@ static void default_lq_deserialize_hello_lq_pair_ff(const uint8_t ** curr, void
> static int default_lq_serialize_tc_lq_pair_ff(unsigned char *buff, void *lq);
> static void default_lq_deserialize_tc_lq_pair_ff(const uint8_t ** curr, void *lq);
>
> -static void default_lq_copy_link2neigh_ff(void *t, void *s);
> +static void default_lq_copy_link2neigh_ff(void *t, void *s, bool force);
> static void default_lq_copy_link2tc_ff(void *target, void *source);
> static void default_lq_clear_ff(void *target);
> static void default_lq_clear_ff_hello(void *target);
> @@ -371,11 +371,18 @@ default_lq_memorize_foreign_hello_ff(void *ptrLocal, void *ptrForeign)
> }
>
> static void
> -default_lq_copy_link2neigh_ff(void *t, void *s)
> +default_lq_copy_link2neigh_ff(void *t, void *s, bool force)
> {
> struct default_lq_ff *target = t;
> struct default_lq_ff_hello *source = s;
> - *target = source->smoothed_lq;
> +
> + if (force) {
> + *target = source->smoothed_lq;
> + return;
> + }
> +
> + target->valueLq = MAX(target->valueLq, source->smoothed_lq.valueLq);
> + target->valueNlq = MAX(target->valueNlq, source->smoothed_lq.valueNlq);
> }
>
> static void
> diff --git a/src/lq_plugin_default_ffeth.c b/src/lq_plugin_default_ffeth.c
> index e78dcd7..0e9408e 100644
> --- a/src/lq_plugin_default_ffeth.c
> +++ b/src/lq_plugin_default_ffeth.c
> @@ -72,7 +72,7 @@ static void default_lq_deserialize_hello_lq_pair_ffeth(const uint8_t ** curr, vo
> static int default_lq_serialize_tc_lq_pair_ffeth(unsigned char *buff, void *lq);
> static void default_lq_deserialize_tc_lq_pair_ffeth(const uint8_t ** curr, void *lq);
>
> -static void default_lq_copy_link2neigh_ffeth(void *t, void *s);
> +static void default_lq_copy_link2neigh_ffeth(void *t, void *s, bool force);
> static void default_lq_copy_link2tc_ffeth(void *target, void *source);
> static void default_lq_clear_ffeth(void *target);
> static void default_lq_clear_ffeth_hello(void *target);
> @@ -410,11 +410,18 @@ default_lq_memorize_foreign_hello_ffeth(void *ptrLocal, void *ptrForeign)
> }
>
> static void
> -default_lq_copy_link2neigh_ffeth(void *t, void *s)
> +default_lq_copy_link2neigh_ffeth(void *t, void *s, bool force)
> {
> struct default_lq_ffeth *target = t;
> struct default_lq_ffeth_hello *source = s;
> - *target = source->smoothed_lq;
> +
> + if (force) {
> + *target = source->smoothed_lq;
> + return;
> + }
> +
> + target->valueLq = MAX(target->valueLq, source->smoothed_lq.valueLq);
> + target->valueNlq = MAX(target->valueNlq, source->smoothed_lq.valueNlq);
> }
>
> static void
> diff --git a/src/lq_plugin_default_float.c b/src/lq_plugin_default_float.c
> index 2e07686..f7e2031 100644
> --- a/src/lq_plugin_default_float.c
> +++ b/src/lq_plugin_default_float.c
> @@ -59,6 +59,7 @@ static int default_lq_serialize_hello_lq_pair_float(unsigned char *buff, void *l
> static void default_lq_deserialize_hello_lq_pair_float(const uint8_t ** curr, void *lq);
> static int default_lq_serialize_tc_lq_pair_float(unsigned char *buff, void *lq);
> static void default_lq_deserialize_tc_lq_pair_float(const uint8_t ** curr, void *lq);
> +static void default_lq_copy_link2neigh_float(void *t, void *s, bool force);
> static void default_lq_copy_link2tc_float(void *target, void *source);
> static void default_lq_clear_float(void *target);
> static const char *default_lq_print_float(void *ptr, char separator, struct lqtextbuffer *buffer);
> @@ -74,7 +75,7 @@ struct lq_handler lq_etx_float_handler = {
>
> &default_lq_packet_loss_worker_float,
> &default_lq_memorize_foreign_hello_float,
> - &default_lq_copy_link2tc_float,
> + &default_lq_copy_link2neigh_float,
> &default_lq_copy_link2tc_float,
> &default_lq_clear_float,
> &default_lq_clear_float,
> @@ -207,6 +208,22 @@ default_lq_memorize_foreign_hello_float(void *ptrLocal, void *ptrForeign)
> }
>
> static void
> +default_lq_copy_link2neigh_float(void *t, void *s, bool force)
> +{
> + struct default_lq_float *target = t;
> + struct default_lq_float *source = s;
> +
> + if (force) {
> + memcpy(target, source, sizeof(struct default_lq_float));
> + return;
> + }
> +
> + target->lq = MAX(target->lq, source->lq);
> + target->nlq = MAX(target->nlq, source->nlq);
> + target->quickstart = MAX(target->quickstart, source->quickstart);
> +}
> +
> +static void
> default_lq_copy_link2tc_float(void *target, void *source)
> {
> memcpy(target, source, sizeof(struct default_lq_float));
> diff --git a/src/lq_plugin_default_fpm.c b/src/lq_plugin_default_fpm.c
> index fbfa0cf..2947f92 100644
> --- a/src/lq_plugin_default_fpm.c
> +++ b/src/lq_plugin_default_fpm.c
> @@ -60,6 +60,7 @@ static int default_lq_serialize_hello_lq_pair_fpm(unsigned char *buff, void *lq)
> static void default_lq_deserialize_hello_lq_pair_fpm(const uint8_t ** curr, void *lq);
> static int default_lq_serialize_tc_lq_pair_fpm(unsigned char *buff, void *lq);
> static void default_lq_deserialize_tc_lq_pair_fpm(const uint8_t ** curr, void *lq);
> +static void default_lq_copy_link2neigh_fpm(void *t, void *s, bool force);
> static void default_lq_copy_link2tc_fpm(void *target, void *source);
> static void default_lq_clear_fpm(void *target);
> static const char *default_lq_print_fpm(void *ptr, char separator, struct lqtextbuffer *buffer);
> @@ -75,7 +76,7 @@ struct lq_handler lq_etx_fpm_handler = {
>
> &default_lq_packet_loss_worker_fpm,
> &default_lq_memorize_foreign_hello_fpm,
> - &default_lq_copy_link2tc_fpm,
> + &default_lq_copy_link2neigh_fpm,
> &default_lq_copy_link2tc_fpm,
> &default_lq_clear_fpm,
> &default_lq_clear_fpm,
> @@ -224,6 +225,22 @@ default_lq_copy_link2tc_fpm(void *target, void *source)
> }
>
> static void
> +default_lq_copy_link2neigh_fpm(void *t, void *s, bool force)
> +{
> + struct default_lq_fpm *target = t;
> + struct default_lq_fpm *source = s;
> +
> + if (force) {
> + memcpy(target, source, sizeof(struct default_lq_fpm));
> + return;
> + }
> +
> + target->valueLq = MAX(target->valueLq, source->valueLq);
> + target->valueNlq = MAX(target->valueNlq, source->valueNlq);
> + target->quickstart = MAX(target->quickstart, source->quickstart);
> +}
> +
> +static void
> default_lq_clear_fpm(void *target)
> {
> memset(target, 0, sizeof(struct default_lq_fpm));
> diff --git a/src/olsr_protocol.h b/src/olsr_protocol.h
> index a995db0..ed3e134 100644
> --- a/src/olsr_protocol.h
> +++ b/src/olsr_protocol.h
> @@ -111,6 +111,83 @@ struct olsr;
> #define HIDE_LINK 4
> #define MAX_LINK 4
>
> +/**
> + * Compare two link types.
> + *
> + * <pre>
> + * +-------------+------+------+--------+------+-----+
> + * | | link_type_new |
> + * | +------+------+--------+------+-----+
> + * | link_type | HIDE | LOST | UNSPEC | ASYM | SYM |
> + * |-------------+------+------+--------+------+-----+
> + * | HIDE | F | T | T | T | T |
> + * | LOST | F | F | T | T | T |
> + * | UNSPEC | F | F | F | T | T |
> + * | ASYM | F | F | F | F | T |
> + * | SYM | F | F | F | F | F |
> + * +-------------+------+------+--------+------+-----+
> + * </pre>
> + *
> + * @param link_type a link type
> + * @param link_type_new a (new) link type
> + * @return true when link_type_new is 'better' than link_type
> + */
> +static INLINE bool link_type_compare(int link_type, int link_type_new) {
> + switch (link_type_new) {
> + case SYM_LINK:
> + switch (link_type) {
> + case SYM_LINK:
> + return false;
> +
> + default:
> + return true;
> + }
> + break;
> +
> + case ASYM_LINK:
> + switch (link_type) {
> + case SYM_LINK:
> + case ASYM_LINK:
> + return false;
> +
> + default:
> + return true;
> + }
> + break;
> +
> + case UNSPEC_LINK:
> + switch (link_type) {
> + case SYM_LINK:
> + case ASYM_LINK:
> + case UNSPEC_LINK:
> + return false;
> +
> + default:
> + return true;
> + }
> + break;
> +
> + case LOST_LINK:
> + switch (link_type) {
> + case SYM_LINK:
> + case ASYM_LINK:
> + case UNSPEC_LINK:
> + case LOST_LINK:
> + return false;
> +
> + default:
> + return true;
> + }
> + break;
> +
> + case HIDE_LINK:
> + return false;
> +
> + default:
> + return true;
> + }
> +}
> +
> static INLINE const char * linkTypeToString(int type) {
> switch (type) {
> case ASYM_LINK:
> @@ -140,6 +217,65 @@ static INLINE const char * linkTypeToString(int type) {
> #define MPR_NEIGH 2
> #define MAX_NEIGH 2
>
> +/**
> + * Compare two neighbour types.
> + *
> + * <pre>
> + * +-------+------+-----+-----+
> + * | | neigh_new |
> + * | +------+-----+-----+
> + * | neigh | NOT | SYM | MPR |
> + * |-------+------+-----+-----+
> + * | NOT | F | T | T |
> + * | SYM | F | F | T |
> + * | MPR | F | F | F |
> + * +-------+------+-----+-----+
> + * </pre>
> + *
> + * @param neigh a neighbour type
> + * @param neigh_new a (new) neighbour type
> + * @return true when neigh_new is 'better' than neigh
> + */
> +static INLINE bool neigh_type_compare(int neigh, int neigh_new) {
> + switch (neigh_new) {
> + case MPR_NEIGH:
> + switch (neigh) {
> + case MPR_NEIGH:
> + return false;
> +
> + default:
> + return true;
> + }
> + break;
> +
> + case SYM_NEIGH:
> + switch (neigh) {
> + case MPR_NEIGH:
> + case SYM_NEIGH:
> + return false;
> +
> + default:
> + return true;
> + }
> + break;
> +
> + case NOT_NEIGH:
> + switch (neigh) {
> + case MPR_NEIGH:
> + case SYM_NEIGH:
> + case NOT_NEIGH:
> + return false;
> +
> + default:
> + return true;
> + }
> + break;
> +
> + default:
> + return true;
> + }
> +}
> +
> /*
> *Neighbor status
> */
>
--
Ferry Huberts
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