CCM PDUs may take a different path through the network depending on the VLAN tag they carry. In order to exercise these paths, it may be advantageous to use a random VLAN tag.
Signed-off-by: Ethan Jackson <[email protected]> --- lib/cfm.c | 13 +++++++++---- lib/cfm.h | 3 ++- vswitchd/bridge.c | 13 +++++++++++-- vswitchd/vswitch.xml | 3 ++- 4 files changed, 24 insertions(+), 8 deletions(-) diff --git a/lib/cfm.c b/lib/cfm.c index 8d90829..10a9428 100644 --- a/lib/cfm.c +++ b/lib/cfm.c @@ -30,6 +30,7 @@ #include "ofpbuf.h" #include "packets.h" #include "poll-loop.h" +#include "random.h" #include "timer.h" #include "timeval.h" #include "unixctl.h" @@ -96,7 +97,7 @@ struct cfm { uint32_t seq; /* The sequence number of our last CCM. */ uint8_t ccm_interval; /* The CCM transmission interval. */ int ccm_interval_ms; /* 'ccm_interval' in milliseconds. */ - uint16_t ccm_vlan; /* Vlan tag of CCM PDUs. */ + uint16_t ccm_vlan; /* Vlan tag of CCM PDUs. UINT16_MAX if random. */ uint8_t ccm_pcp; /* Priority of CCM PDUs. */ uint8_t maid[CCM_MAID_LEN]; /* The MAID of this CFM. */ @@ -391,13 +392,17 @@ void cfm_compose_ccm(struct cfm *cfm, struct ofpbuf *packet, uint8_t eth_src[ETH_ADDR_LEN]) { + uint16_t ccm_vlan; struct ccm *ccm; timer_set_duration(&cfm->tx_timer, cfm->ccm_interval_ms); eth_compose(packet, cfm_ccm_addr(cfm), eth_src, ETH_TYPE_CFM, sizeof *ccm); - if (cfm->ccm_vlan || cfm->ccm_pcp) { - uint16_t tci = cfm->ccm_vlan | (cfm->ccm_pcp << VLAN_PCP_SHIFT); + ccm_vlan = cfm->ccm_vlan != UINT16_MAX ? cfm->ccm_vlan : random_uint16(); + ccm_vlan = ccm_vlan & VLAN_VID_MASK; + + if (ccm_vlan || cfm->ccm_pcp) { + uint16_t tci = ccm_vlan | (cfm->ccm_pcp << VLAN_PCP_SHIFT); eth_push_vlan(packet, htons(tci)); } @@ -455,7 +460,7 @@ cfm_configure(struct cfm *cfm, const struct cfm_settings *s) interval = ms_to_ccm_interval(s->interval); interval_ms = ccm_interval_to_ms(interval); - cfm->ccm_vlan = s->ccm_vlan & VLAN_VID_MASK; + cfm->ccm_vlan = s->ccm_vlan; cfm->ccm_pcp = s->ccm_pcp & (VLAN_PCP_MASK >> VLAN_PCP_SHIFT); if (cfm->extended && interval_ms != s->interval) { interval = 0; diff --git a/lib/cfm.h b/lib/cfm.h index 6d23293..c706c70 100644 --- a/lib/cfm.h +++ b/lib/cfm.h @@ -51,7 +51,8 @@ struct cfm_settings { int interval; /* The requested transmission interval. */ bool extended; /* Run in extended mode. */ bool opup; /* Operational State. */ - uint16_t ccm_vlan; /* CCM Vlan tag. Zero if none. */ + uint16_t ccm_vlan; /* CCM Vlan tag. Zero if none. + UINT16_MAX if random. */ uint8_t ccm_pcp; /* CCM Priority. Zero if none. */ }; diff --git a/vswitchd/bridge.c b/vswitchd/bridge.c index 4761cbf..64d7c4d 100644 --- a/vswitchd/bridge.c +++ b/vswitchd/bridge.c @@ -3226,6 +3226,7 @@ iface_configure_cfm(struct iface *iface) { const struct ovsrec_interface *cfg = iface->cfg; const char *extended_str, *opstate_str; + const char *cfm_ccm_vlan; struct cfm_settings s; if (!cfg->n_cfm_mpid) { @@ -3236,14 +3237,22 @@ iface_configure_cfm(struct iface *iface) s.mpid = *cfg->cfm_mpid; s.interval = atoi(get_interface_other_config(iface->cfg, "cfm_interval", "0")); - s.ccm_vlan = atoi(get_interface_other_config(iface->cfg, "cfm_ccm_vlan", - "0")); + cfm_ccm_vlan = get_interface_other_config(iface->cfg, "cfm_ccm_vlan", "0"); s.ccm_pcp = atoi(get_interface_other_config(iface->cfg, "cfm_ccm_pcp", "0")); if (s.interval <= 0) { s.interval = 1000; } + if (!strcasecmp("random", cfm_ccm_vlan)) { + s.ccm_vlan = UINT16_MAX; + } else { + s.ccm_vlan = atoi(cfm_ccm_vlan); + if (s.ccm_vlan == UINT16_MAX) { + s.ccm_vlan = 0; + } + } + extended_str = get_interface_other_config(iface->cfg, "cfm_extended", "false"); s.extended = !strcasecmp("true", extended_str); diff --git a/vswitchd/vswitch.xml b/vswitchd/vswitch.xml index 7739793..3ea6810 100644 --- a/vswitchd/vswitch.xml +++ b/vswitchd/vswitch.xml @@ -1768,7 +1768,8 @@ <column name="other_config" key="cfm_ccm_vlan" type='{"type": "integer", "minInteger": 1, "maxInteger": 4095}'> When set, the CFM module will apply a VLAN tag to all CCMs it generates - with the given value. + with the given value. May be the string "random" in which case each + CCM will be tagged with a different randomly generated VLAN. </column> <column name="other_config" key="cfm_ccm_pcp" -- 1.7.9.2 _______________________________________________ dev mailing list [email protected] http://openvswitch.org/mailman/listinfo/dev
