<p>In Linux, there is also a plenty of obscure route attributes mostly focused
on tuning TCP performance of local connections. BIRD supports most of these
attributes, see Linux or iproute2 documentation for their meaning. Attributes
-<cf/krt_lock_*/ and <cf/krt_feature_*/ have type bool, others have type int.
-Supported attributes are:
+<cf/krt_lock_*/ and <cf/krt_feature_*/ have type bool, <cf/krt_congctl/ has type
+string, others have type int. Supported attributes are:
<cf/krt_mtu/, <cf/krt_lock_mtu/, <cf/krt_window/, <cf/krt_lock_window/,
<cf/krt_rtt/, <cf/krt_lock_rtt/, <cf/krt_rttvar/, <cf/krt_lock_rttvar/,
<cf/krt_sstresh/, <cf/krt_lock_sstresh/, <cf/krt_cwnd/, <cf/krt_lock_cwnd/,
<cf/krt_advmss/, <cf/krt_lock_advmss/, <cf/krt_reordering/, <cf/krt_lock_reordering/,
<cf/krt_hoplimit/, <cf/krt_lock_hoplimit/, <cf/krt_rto_min/, <cf/krt_lock_rto_min/,
-<cf/krt_initcwnd/, <cf/krt_initrwnd/, <cf/krt_quickack/,
+<cf/krt_initcwnd/, <cf/krt_initrwnd/, <cf/krt_quickack/, <cf/krt_congctl/,
<cf/krt_feature_ecn/, <cf/krt_feature_allfrag/
<sect1>Example
KRT_PREFSRC, KRT_REALM, KRT_SCOPE, KRT_MTU, KRT_WINDOW,
KRT_RTT, KRT_RTTVAR, KRT_SSTRESH, KRT_CWND, KRT_ADVMSS, KRT_REORDERING,
KRT_HOPLIMIT, KRT_INITCWND, KRT_RTO_MIN, KRT_INITRWND, KRT_QUICKACK,
- KRT_LOCK_MTU, KRT_LOCK_WINDOW, KRT_LOCK_RTT, KRT_LOCK_RTTVAR,
+ KRT_CONGCTL, KRT_LOCK_MTU, KRT_LOCK_WINDOW, KRT_LOCK_RTT, KRT_LOCK_RTTVAR,
KRT_LOCK_SSTRESH, KRT_LOCK_CWND, KRT_LOCK_ADVMSS, KRT_LOCK_REORDERING,
KRT_LOCK_HOPLIMIT, KRT_LOCK_RTO_MIN, KRT_FEATURE_ECN, KRT_FEATURE_ALLFRAG)
dynamic_attr: KRT_RTO_MIN { $$ = f_new_dynamic_attr(EAF_TYPE_INT, T_INT, EA_KRT_RTO_MIN); } ;
dynamic_attr: KRT_INITRWND { $$ = f_new_dynamic_attr(EAF_TYPE_INT, T_INT, EA_KRT_INITRWND); } ;
dynamic_attr: KRT_QUICKACK { $$ = f_new_dynamic_attr(EAF_TYPE_INT, T_INT, EA_KRT_QUICKACK); } ;
+dynamic_attr: KRT_CONGCTL { $$ = f_new_dynamic_attr(EAF_TYPE_STRING, T_STRING, EA_KRT_CONGCTL); } ;
/* Bits of EA_KRT_LOCK, based on RTAX_* constants */
static inline u32 rta_get_u32(struct rtattr *a)
{ return *(u32 *) RTA_DATA(a); }
+static inline const char *rta_get_str(struct rtattr *a)
+{ return RTA_DATA(a); }
+
static inline ip4_addr rta_get_ip4(struct rtattr *a)
{ return ip4_ntoh(*(ip4_addr *) RTA_DATA(a)); }
nl_add_attr(h, bufsize, code, &data, 4);
}
+static inline void
+nl_add_attr_str(struct nlmsghdr *h, unsigned bufsize, int code, const char *str)
+{
+ nl_add_attr(h, bufsize, code, str, strlen(str) + 1);
+}
+
static inline void
nl_add_attr_ip4(struct nlmsghdr *h, uint bufsize, int code, ip4_addr ip4)
{
return NULL;
}
+STATIC_ASSERT(EA_KRT_METRICS + RTAX_CC_ALGO == EA_KRT_CONGCTL);
+
static void
-nl_add_metrics(struct nlmsghdr *h, uint bufsize, u32 *metrics, int max)
+nl_add_metrics(struct nlmsghdr *h, uint bufsize, u32 *metrics, const char *cc_algo, int max)
{
struct rtattr *a = nl_open_attr(h, bufsize, RTA_METRICS);
int t;
for (t = 1; t < max; t++)
if (metrics[0] & (1 << t))
- nl_add_attr_u32(h, bufsize, t, metrics[t]);
+ if (t == RTAX_CC_ALGO)
+ nl_add_attr_str(h, bufsize, t, cc_algo);
+ else
+ nl_add_attr_u32(h, bufsize, t, metrics[t]);
nl_close_attr(h, a);
}
static int
-nl_parse_metrics(struct rtattr *hdr, u32 *metrics, int max)
+nl_parse_metrics(struct rtattr *hdr, u32 *metrics, const char **cc_algo, int max)
{
struct rtattr *a = RTA_DATA(hdr);
int len = RTA_PAYLOAD(hdr);
metrics[0] = 0;
for (; RTA_OK(a, len); a = RTA_NEXT(a, len))
{
- if (a->rta_type == RTA_UNSPEC)
+ if (a->rta_type == RTAX_UNSPEC)
continue;
if (a->rta_type >= max)
continue;
- if (RTA_PAYLOAD(a) != 4)
- return -1;
+ if (a->rta_type == RTAX_CC_ALGO)
+ {
+ *cc_algo = rta_get_str(a);
+ int slen = RTA_PAYLOAD(a);
+
+ if (!slen || ((*cc_algo)[slen - 1] != 0))
+ return -1;
- metrics[0] |= 1 << a->rta_type;
- metrics[a->rta_type] = rta_get_u32(a);
+ metrics[0] |= 1 << a->rta_type;
+ metrics[a->rta_type] = 0;
+ }
+ else
+ {
+ if (RTA_PAYLOAD(a) != 4)
+ return -1;
+
+ metrics[0] |= 1 << a->rta_type;
+ metrics[a->rta_type] = rta_get_u32(a);
+ }
}
if (len > 0)
u32 metrics[KRT_METRICS_MAX];
+ const char *cc_algo = NULL;
metrics[0] = 0;
struct ea_walk_state ews = { .eattrs = eattrs };
{
int id = ea->id - EA_KRT_METRICS;
metrics[0] |= 1 << id;
- metrics[id] = ea->u.data;
+
+ if (id == RTAX_CC_ALGO)
+ cc_algo = ea->u.ptr->data;
+ else
+ metrics[id] = ea->u.data;
}
if (metrics[0])
- nl_add_metrics(&r->h, rsize, metrics, KRT_METRICS_MAX);
+ nl_add_metrics(&r->h, rsize, metrics, cc_algo, KRT_METRICS_MAX);
switch (a->dest)
{
if (a[RTA_METRICS])
{
u32 metrics[KRT_METRICS_MAX];
+ const char *cc_algo = NULL;
ea_list *ea = lp_alloc(s->pool, sizeof(ea_list) + KRT_METRICS_MAX * sizeof(eattr));
int t, n = 0;
- if (nl_parse_metrics(a[RTA_METRICS], metrics, ARRAY_SIZE(metrics)) < 0)
+ if (nl_parse_metrics(a[RTA_METRICS], metrics, &cc_algo, ARRAY_SIZE(metrics)) < 0)
{
log(L_ERR "KRT: Received route %N with strange RTA_METRICS attribute", net->n.addr);
return;
for (t = 1; t < KRT_METRICS_MAX; t++)
if (metrics[0] & (1 << t))
- ea->attrs[n++] = (eattr) {
- .id = EA_CODE(PROTOCOL_KERNEL, KRT_METRICS_OFFSET + t),
- .flags = 0,
- .type = EAF_TYPE_INT, /* FIXME: Some are EAF_TYPE_BITFIELD */
- .u.data = metrics[t],
- };
+ if (t == RTAX_CC_ALGO)
+ {
+ struct adata *ad = lp_alloc_adata(s->pool, strlen(cc_algo));
+ memcpy(ad->data, cc_algo, ad->length);
+
+ ea->attrs[n++] = (eattr) {
+ .id = EA_KRT_CONGCTL,
+ .type = EAF_TYPE_STRING,
+ .u.ptr = ad,
+ };
+ }
+ else
+ {
+ ea->attrs[n++] = (eattr) {
+ .id = EA_KRT_METRICS + t,
+ .type = EAF_TYPE_INT, /* FIXME: Some are EAF_TYPE_BITFIELD */
+ .u.data = metrics[t],
+ };
+ }
if (n > 0)
{
static const char *krt_metrics_names[KRT_METRICS_MAX] = {
NULL, "lock", "mtu", "window", "rtt", "rttvar", "sstresh", "cwnd", "advmss",
- "reordering", "hoplimit", "initcwnd", "features", "rto_min", "initrwnd", "quickack"
+ "reordering", "hoplimit", "initcwnd", "features", "rto_min", "initrwnd", "quickack",
+ "congctl"
};
static const char *krt_features_names[KRT_FEATURES_MAX] = {