#include <vnet/vnet.h>
#include <vnet/ip/ip.h>
-static int comma_split (u8 *s, u8 **a, u8 **b)
+/** \file
+
+ Dynamically compute IP feature subgraph ordering by performing a
+ topological sort across a set of "feature A before feature B" and
+ "feature C after feature B" constraints.
+
+ Use the topological sort result to set up vnet_config_main_t's for
+ use at runtime.
+
+ Feature subgraph arcs are simple enough. They start at specific
+ fixed nodes, and end at specific fixed nodes. In between, a
+ per-interface current feature configuration dictates which
+ additional nodes each packet visits. Each so-called feature node
+ can [of course] drop any specific packet.
+
+ See ip4_forward.c, ip6_forward.c in this directory to see the
+ current rx-unicast, rx-multicast, and tx feature subgraph arc
+ definitions.
+
+ Let's say that we wish to add a new feature to the ip4 unicast
+ feature subgraph arc, which needs to run before @c ip4-lookup. In
+ either base code or a plugin,
+ <CODE><PRE>
+ #include <vnet/ip/ip_feature_registration.h>
+ </PRE></CODE>
+
+ and add the new feature as shown:
+
+ <CODE><PRE>
+ VNET_IP4_UNICAST_FEATURE_INIT (ip4_lookup, static) =
+ {
+ .node_name = "my-ip4-unicast-feature",
+ .runs_before = ORDER_CONSTRAINTS {"ip4-lookup", 0}
+ .feature_index = &my_feature_index,
+ };
+ </PRE></CODE>
+
+ Here's the standard coding pattern to enable / disable
+ @c my-ip4-unicast-feature on an interface:
+
+ <CODE><PRE>
+ ip4_main_t *im = &ip4_main;
+ ip_lookup_main_t *lm = &im->lookup_main;
+ ip_config_main_t *rx_cm =
+ &lm->feature_config_mains[VNET_IP_RX_UNICAST_FEAT];
+
+ sw_if_index = <interface-handle>
+ ci = rx_cm->config_index_by_sw_if_index[sw_if_index];
+ ci = (is_add
+ ? vnet_config_add_feature
+ : vnet_config_del_feature)
+ (vm, &rx_cm->config_main,
+ ci,
+ my_feature_index,
+ 0 / * &config struct if feature uses private config data * /,
+ 0 / * sizeof config struct if feature uses private config data * /);
+ rx_cm->config_index_by_sw_if_index[sw_if_index] = ci;
+ </PRE></CODE>
+
+ For tx features, add this line after setting
+ <CODE><PRE>
+ tx_cm->config_index_by_sw_if_index = ci.
+ </PRE></CODE>
+
+ This maintains a
+ per-interface "at least one TX feature enabled" bitmap:
+
+ <CODE><PRE>
+ vnet_config_update_tx_feature_count (lm, tx_cm, sw_if_index, is_add);
+ </PRE></CODE>
+
+ Here's how to obtain the correct next node index in packet
+ processing code, aka in the implementation of @c my-ip4-unicast-feature:
+
+ <CODE><PRE>
+ ip_lookup_main_t * lm = sm->ip4_lookup_main;
+ ip_config_main_t * cm = &lm->feature_config_mains[VNET_IP_RX_UNICAST_FEAT];
+
+ Call @c vnet_get_config_data to set next0, and to advance
+ @c b0->current_config_index:
+
+ config_data0 = vnet_get_config_data (&cm->config_main,
+ &b0->current_config_index,
+ &next0,
+ 0 / * sizeof config data * /);
+ </PRE></CODE>
+
+ Nodes are free to drop or otherwise redirect packets. Packets
+ which "pass" should be enqueued via the next0 arc computed by
+ vnet_get_config_data.
+*/
+
+static int
+comma_split (u8 * s, u8 ** a, u8 ** b)
{
*a = s;
else
return 1;
- *b = (u8 *) (s+1);
+ *b = (u8 *) (s + 1);
return 0;
}
clib_error_t *
ip_feature_init_cast (vlib_main_t * vm,
- ip_config_main_t * cm,
- vnet_config_main_t * vcm,
- char **feature_start_nodes,
- int num_feature_start_nodes,
- vnet_cast_t cast,
- int is_ip4)
+ ip_config_main_t * cm,
+ vnet_config_main_t * vcm,
+ char **feature_start_nodes,
+ int num_feature_start_nodes,
+ vnet_cast_t cast, int is_ip4)
{
- uword * index_by_name;
- uword * reg_by_index;
- u8 ** node_names = 0;
- u8 * node_name;
- char ** these_constraints;
- char * this_constraint_c;
- u8 ** constraints = 0;
- u8 * constraint_tuple;
- u8 * this_constraint;
- u8 ** orig, ** closure;
- uword * p;
+ uword *index_by_name;
+ uword *reg_by_index;
+ u8 **node_names = 0;
+ u8 *node_name;
+ char **these_constraints;
+ char *this_constraint_c;
+ u8 **constraints = 0;
+ u8 *constraint_tuple;
+ u8 *this_constraint;
+ u8 **orig, **closure;
+ uword *p;
int i, j, k;
- u8 * a_name, * b_name;
+ u8 *a_name, *b_name;
int a_index, b_index;
int n_features;
- u32 * result = 0;
- vnet_ip_feature_registration_t * this_reg, * first_reg = 0;
- char ** feature_nodes = 0;
- hash_pair_t * hp;
- u8 ** keys_to_delete = 0;
- ip4_main_t * im4 = &ip4_main;
- ip6_main_t * im6 = &ip6_main;
+ u32 *result = 0;
+ vnet_ip_feature_registration_t *this_reg, *first_reg = 0;
+ char **feature_nodes = 0;
+ hash_pair_t *hp;
+ u8 **keys_to_delete = 0;
+ ip4_main_t *im4 = &ip4_main;
+ ip6_main_t *im6 = &ip6_main;
index_by_name = hash_create_string (0, sizeof (uword));
reg_by_index = hash_create (0, sizeof (uword));
if (cast == VNET_IP_RX_UNICAST_FEAT)
{
if (is_ip4)
- first_reg = im4->next_uc_feature;
+ first_reg = im4->next_uc_feature;
else
- first_reg = im6->next_uc_feature;
+ first_reg = im6->next_uc_feature;
}
else if (cast == VNET_IP_RX_MULTICAST_FEAT)
{
if (is_ip4)
- first_reg = im4->next_mc_feature;
+ first_reg = im4->next_mc_feature;
else
- first_reg = im6->next_mc_feature;
- }
+ first_reg = im6->next_mc_feature;
+ }
else if (cast == VNET_IP_TX_FEAT)
{
if (is_ip4)
- first_reg = im4->next_tx_feature;
+ first_reg = im4->next_tx_feature;
else
- first_reg = im6->next_tx_feature;
+ first_reg = im6->next_tx_feature;
}
-
+
this_reg = first_reg;
/* pass 1, collect feature node names, construct a before b pairs */
while (this_reg)
{
node_name = format (0, "%s%c", this_reg->node_name, 0);
- hash_set (reg_by_index, vec_len(node_names), (uword) this_reg);
+ hash_set (reg_by_index, vec_len (node_names), (uword) this_reg);
- hash_set_mem (index_by_name, node_name, vec_len(node_names));
+ hash_set_mem (index_by_name, node_name, vec_len (node_names));
vec_add1 (node_names, node_name);
these_constraints = this_reg->runs_before;
- while (these_constraints && these_constraints [0])
- {
- this_constraint_c = these_constraints[0];
+ while (these_constraints && these_constraints[0])
+ {
+ this_constraint_c = these_constraints[0];
- constraint_tuple = format (0, "%s,%s%c", node_name,
- this_constraint_c, 0);
- vec_add1 (constraints, constraint_tuple);
- these_constraints++;
- }
+ constraint_tuple = format (0, "%s,%s%c", node_name,
+ this_constraint_c, 0);
+ vec_add1 (constraints, constraint_tuple);
+ these_constraints++;
+ }
these_constraints = this_reg->runs_after;
- while (these_constraints && these_constraints [0])
- {
- this_constraint_c = these_constraints[0];
+ while (these_constraints && these_constraints[0])
+ {
+ this_constraint_c = these_constraints[0];
- constraint_tuple = format (0, "%s,%s%c",
- this_constraint_c,
- node_name, 0);
- vec_add1 (constraints, constraint_tuple);
- these_constraints++;
- }
+ constraint_tuple = format (0, "%s,%s%c",
+ this_constraint_c, node_name, 0);
+ vec_add1 (constraints, constraint_tuple);
+ these_constraints++;
+ }
this_reg = this_reg->next;
}
this_constraint = constraints[i];
if (comma_split (this_constraint, &a_name, &b_name))
- return clib_error_return (0, "comma_split failed!");
-
+ return clib_error_return (0, "comma_split failed!");
+
p = hash_get_mem (index_by_name, a_name);
- /*
+ /*
* Note: the next two errors mean that the xxx_FEATURE_INIT macros are
* b0rked. As in: if you code "A depends on B," and you forget
- * to define a FEATURE_INIT macro for B, you lose.
+ * to define a FEATURE_INIT macro for B, you lose.
* Nonexistent graph nodes are tolerated.
*/
if (p == 0)
- return clib_error_return (0, "feature node '%s' not found", a_name);
+ return clib_error_return (0, "feature node '%s' not found", a_name);
a_index = p[0];
p = hash_get_mem (index_by_name, b_name);
if (p == 0)
- return clib_error_return (0, "feature node '%s' not found", b_name);
+ return clib_error_return (0, "feature node '%s' not found", b_name);
b_index = p[0];
/* add a before b to the original set of constraints */
orig[a_index][b_index] = 1;
vec_free (this_constraint);
}
-
+
/* Compute the positive transitive closure of the original constraints */
closure = clib_ptclosure (orig);
/* Compute a partial order across feature nodes, if one exists. */
- again:
+again:
for (i = 0; i < n_features; i++)
{
for (j = 0; j < n_features; j++)
- {
- if (closure[i][j])
- goto item_constrained;
- }
+ {
+ if (closure[i][j])
+ goto item_constrained;
+ }
/* Item i can be output */
vec_add1 (result, i);
{
- for (k = 0; k < n_features; k++)
- closure [k][i] = 0;
- /*
- * Add a "Magic" a before a constraint.
- * This means we'll never output it again
- */
- closure [i][i] = 1;
- goto again;
+ for (k = 0; k < n_features; k++)
+ closure[k][i] = 0;
+ /*
+ * Add a "Magic" a before a constraint.
+ * This means we'll never output it again
+ */
+ closure[i][i] = 1;
+ goto again;
}
item_constrained:
;
/* see if we got a partial order... */
if (vec_len (result) != n_features)
- return clib_error_return
- (0, "ip%s_feature_init_cast (cast=%d), no partial order!",
- is_ip4 ? "4" : "6", cast);
+ return clib_error_return
+ (0, "ip%s_feature_init_cast (cast=%d), no partial order!",
+ is_ip4 ? "4" : "6", cast);
- /*
+ /*
* We win.
* Bind the index variables, and output the feature node name vector
* using the partial order we just computed. Result is in stack
* is output first, etc.
*/
- for (i = n_features-1; i >= 0; i--)
+ for (i = n_features - 1; i >= 0; i--)
{
p = hash_get (reg_by_index, result[i]);
ASSERT (p != 0);
- this_reg = (vnet_ip_feature_registration_t *)p[0];
- *this_reg->feature_index = n_features - (i+1);
+ this_reg = (vnet_ip_feature_registration_t *) p[0];
+ *this_reg->feature_index = n_features - (i + 1);
vec_add1 (feature_nodes, this_reg->node_name);
}
-
+
/* Set up the config infrastructure */
vnet_config_init (vm, vcm,
- feature_start_nodes,
- num_feature_start_nodes,
- feature_nodes,
- vec_len(feature_nodes));
+ feature_start_nodes,
+ num_feature_start_nodes,
+ feature_nodes, vec_len (feature_nodes));
/* Save a copy for show command */
if (is_ip4)
im6->feature_nodes[cast] = feature_nodes;
/* Finally, clean up all the shit we allocated */
+ /* *INDENT-OFF* */
hash_foreach_pair (hp, index_by_name,
({
vec_add1 (keys_to_delete, (u8 *)hp->key);
}));
+ /* *INDENT-ON* */
hash_free (index_by_name);
- for (i = 0; i < vec_len(keys_to_delete); i++)
+ for (i = 0; i < vec_len (keys_to_delete); i++)
vec_free (keys_to_delete[i]);
vec_free (keys_to_delete);
hash_free (reg_by_index);
_(6, VNET_IP_RX_MULTICAST_FEAT, "ip6 multicast") \
_(6, VNET_IP_TX_FEAT, "ip6 output")
+/** Display the set of available ip features.
+ Useful for verifying that expected features are present
+*/
+
static clib_error_t *
show_ip_features_command_fn (vlib_main_t * vm,
- unformat_input_t * input,
- vlib_cli_command_t * cmd)
+ unformat_input_t * input,
+ vlib_cli_command_t * cmd)
{
- ip4_main_t * im4 = &ip4_main;
- ip6_main_t * im6 = &ip6_main;
+ ip4_main_t *im4 = &ip4_main;
+ ip6_main_t *im6 = &ip6_main;
int i;
- char ** features;
+ char **features;
vlib_cli_output (vm, "Available IP feature nodes");
return 0;
}
+/* *INDENT-OFF* */
VLIB_CLI_COMMAND (show_ip_features_command, static) = {
.path = "show ip features",
.short_help = "show ip features",
.function = show_ip_features_command_fn,
};
+/* *INDENT-ON* */
+
+/** Display the set of IP features configured on a specific interface
+ */
static clib_error_t *
show_ip_interface_features_command_fn (vlib_main_t * vm,
- unformat_input_t * input,
- vlib_cli_command_t * cmd)
+ unformat_input_t * input,
+ vlib_cli_command_t * cmd)
{
- vnet_main_t * vnm = vnet_get_main();
- ip4_main_t * im4 = &ip4_main;
- ip_lookup_main_t * lm4 = &im4->lookup_main;
- ip6_main_t * im6 = &ip6_main;
- ip_lookup_main_t * lm6 = &im6->lookup_main;
-
- ip_lookup_main_t * lm;
- ip_config_main_t * cm;
- vnet_config_main_t * vcm;
- vnet_config_t * cfg;
+ vnet_main_t *vnm = vnet_get_main ();
+ ip4_main_t *im4 = &ip4_main;
+ ip_lookup_main_t *lm4 = &im4->lookup_main;
+ ip6_main_t *im6 = &ip6_main;
+ ip_lookup_main_t *lm6 = &im6->lookup_main;
+
+ ip_lookup_main_t *lm;
+ ip_config_main_t *cm;
+ vnet_config_main_t *vcm;
+ vnet_config_t *cfg;
u32 cfg_index;
- vnet_config_feature_t * feat;
- vlib_node_t * n;
+ vnet_config_feature_t *feat;
+ vlib_node_t *n;
u32 sw_if_index;
u32 node_index;
u32 current_config_index;
int i, af;
u32 cast;
- if (! unformat (input, "%U", unformat_vnet_sw_interface,
- vnm, &sw_if_index))
+ if (!unformat (input, "%U", unformat_vnet_sw_interface, vnm, &sw_if_index))
return clib_error_return (0, "Interface not specified...");
vlib_cli_output (vm, "IP feature paths configured on %U...",
- format_vnet_sw_if_index_name, vnm, sw_if_index);
+ format_vnet_sw_if_index_name, vnm, sw_if_index);
+
-
for (af = 0; af < 2; af++)
{
if (af == 0)
- lm = lm4;
+ lm = lm4;
else
- lm = lm6;
+ lm = lm6;
for (cast = VNET_IP_RX_UNICAST_FEAT; cast < VNET_N_IP_FEAT; cast++)
- {
- cm = lm->feature_config_mains + cast;
- vcm = &cm->config_main;
-
- vlib_cli_output (vm, "\nipv%s %scast:",
- (af == 0) ? "4" : "6",
- cast == VNET_IP_RX_UNICAST_FEAT ?
- "uni": "multi");
-
- current_config_index = vec_elt (cm->config_index_by_sw_if_index,
- sw_if_index);
-
- ASSERT(current_config_index
- < vec_len (vcm->config_pool_index_by_user_index));
-
- cfg_index =
- vcm->config_pool_index_by_user_index[current_config_index];
- cfg = pool_elt_at_index (vcm->config_pool, cfg_index);
-
- for (i = 0; i < vec_len(cfg->features); i++)
- {
- feat = cfg->features + i;
- node_index = feat->node_index;
- n = vlib_get_node (vm, node_index);
- vlib_cli_output (vm, " %v", n->name);
- }
- }
+ {
+ cm = lm->feature_config_mains + cast;
+ vcm = &cm->config_main;
+
+ vlib_cli_output (vm, "\nipv%s %scast:",
+ (af == 0) ? "4" : "6",
+ cast == VNET_IP_RX_UNICAST_FEAT ? "uni" : "multi");
+
+ current_config_index = vec_elt (cm->config_index_by_sw_if_index,
+ sw_if_index);
+
+ ASSERT (current_config_index
+ < vec_len (vcm->config_pool_index_by_user_index));
+
+ cfg_index =
+ vcm->config_pool_index_by_user_index[current_config_index];
+ cfg = pool_elt_at_index (vcm->config_pool, cfg_index);
+
+ for (i = 0; i < vec_len (cfg->features); i++)
+ {
+ feat = cfg->features + i;
+ node_index = feat->node_index;
+ n = vlib_get_node (vm, node_index);
+ vlib_cli_output (vm, " %v", n->name);
+ }
+ }
}
return 0;
}
+/* *INDENT-OFF* */
VLIB_CLI_COMMAND (show_ip_interface_features_command, static) = {
.path = "show ip interface features",
.short_help = "show ip interface features <intfc>",
.function = show_ip_interface_features_command_fn,
};
+/* *INDENT-ON* */
-
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
Code Review / vpp.git / commitdiff