--- /dev/null
+/*
+ * Copyright (c) 2020 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <urpf/urpf.h>
+
+#include <vnet/fib/fib_table.h>
+
+/* *INDENT-OFF* */
+static const char *urpf_feat_arcs[N_AF][VLIB_N_DIR] =
+{
+ [AF_IP4] = {
+ [VLIB_RX] = "ip4-unicast",
+ [VLIB_TX] = "ip4-output",
+ },
+ [AF_IP6] = {
+ [VLIB_RX] = "ip6-unicast",
+ [VLIB_TX] = "ip6-output",
+ },
+};
+
+static const char *urpf_feats[N_AF][VLIB_N_DIR][URPF_N_MODES] =
+{
+ [AF_IP4] = {
+ [VLIB_RX] = {
+ [URPF_MODE_STRICT] = "ip4-rx-urpf-strict",
+ [URPF_MODE_LOOSE] = "ip4-rx-urpf-loose",
+ },
+ [VLIB_TX] = {
+ [URPF_MODE_STRICT] = "ip4-tx-urpf-strict",
+ [URPF_MODE_LOOSE] = "ip4-tx-urpf-loose",
+ },
+ },
+ [AF_IP6] = {
+ [VLIB_RX] = {
+ [URPF_MODE_STRICT] = "ip6-rx-urpf-strict",
+ [URPF_MODE_LOOSE] = "ip6-rx-urpf-loose",
+ },
+ [VLIB_TX] = {
+ [URPF_MODE_STRICT] = "ip6-tx-urpf-strict",
+ [URPF_MODE_LOOSE] = "ip6-tx-urpf-loose",
+ },
+ },
+};
+/* *INDENT-ON* */
+
+/**
+ * Per-af, per-direction, per-interface uRPF configs
+ */
+static urpf_mode_t *urpf_cfgs[N_AF][VLIB_N_DIR];
+
+u8 *
+format_urpf_mode (u8 * s, va_list * a)
+{
+ urpf_mode_t mode = va_arg (*a, int);
+
+ switch (mode)
+ {
+#define _(a,b) \
+ case URPF_MODE_##a: \
+ return (format (s, "%s", b));
+ foreach_urpf_mode
+#undef _
+ }
+
+ return (format (s, "unknown"));
+}
+
+static uword
+unformat_urpf_mode (unformat_input_t * input, va_list * args)
+{
+ urpf_mode_t *mode = va_arg (*args, urpf_mode_t *);
+
+ if (0)
+ ;
+#define _(a,b) \
+ else if (unformat (input, b)) \
+ { \
+ *mode = URPF_MODE_##a; \
+ return (1); \
+ }
+ foreach_urpf_mode
+#undef _
+ return 0;
+}
+
+void
+urpf_update (urpf_mode_t mode,
+ u32 sw_if_index, ip_address_family_t af, vlib_dir_t dir)
+{
+ urpf_mode_t old;
+
+ vec_validate_init_empty (urpf_cfgs[af][dir], sw_if_index, URPF_MODE_OFF);
+ old = urpf_cfgs[af][dir][sw_if_index];
+
+ if (mode != old)
+ {
+ if (URPF_MODE_OFF != old)
+ /* disable what we have */
+ vnet_feature_enable_disable (urpf_feat_arcs[af][dir],
+ urpf_feats[af][dir][old],
+ sw_if_index, 0, 0, 0);
+
+ if (URPF_MODE_OFF != mode)
+ /* enable what's new */
+ vnet_feature_enable_disable (urpf_feat_arcs[af][dir],
+ urpf_feats[af][dir][mode],
+ sw_if_index, 1, 0, 0);
+ }
+ /* else - no change to existing config */
+
+ urpf_cfgs[af][dir][sw_if_index] = mode;
+}
+
+static clib_error_t *
+urpf_cli_update (vlib_main_t * vm,
+ unformat_input_t * input, vlib_cli_command_t * cmd)
+{
+ unformat_input_t _line_input, *line_input = &_line_input;
+ vnet_main_t *vnm = vnet_get_main ();
+ clib_error_t *error = NULL;
+ ip_address_family_t af;
+ urpf_mode_t mode;
+ u32 sw_if_index;
+ vlib_dir_t dir;
+
+ sw_if_index = ~0;
+ af = AF_IP4;
+ dir = VLIB_RX;
+ mode = URPF_MODE_STRICT;
+
+ if (!unformat_user (input, unformat_line_input, line_input))
+ return 0;
+
+ while (unformat_check_input (line_input) != UNFORMAT_END_OF_INPUT)
+ {
+ if (unformat (line_input, "%U",
+ unformat_vnet_sw_interface, vnm, &sw_if_index))
+ ;
+ else if (unformat (line_input, "%U", unformat_urpf_mode, &mode))
+ ;
+ else if (unformat (line_input, "%U", unformat_ip_address_family, &af))
+ ;
+ else if (unformat (line_input, "%U", unformat_vlib_rx_tx, &dir))
+ ;
+ else
+ {
+ error = unformat_parse_error (line_input);
+ goto done;
+ }
+ }
+
+ if (~0 == sw_if_index)
+ {
+ error = clib_error_return (0, "unknown interface `%U'",
+ format_unformat_error, line_input);
+ goto done;
+ }
+
+ urpf_update (mode, sw_if_index, af, dir);
+done:
+ unformat_free (line_input);
+
+ return error;
+}
+
+/*?
+ * This command configures uRPF on an interface.
+ * Two flavours are supported (the default is strict):
+ * - loose: accept ingress packet if there is a route to reach the source
+ * - strict: accept ingress packet if it arrived on an interface which
+ * the route to the source uses. i.e. an interface that the source
+ * is reachable via.
+ *
+ * @cliexpar
+ * @parblock
+ * Example of graph node before range checking is enabled:
+ * @cliexstart{show vlib graph ip4-rx-urpf-strict}
+ * Name Next Previous
+ * ip4-rx-urpf-strict ip4-drop [0]
+ * @cliexend
+ *
+ * Example of how to enable unicast source checking on an interface:
+ * @cliexcmd{set urpf ip4 rx GigabitEthernet2/0/0 loose}
+ *
+ * Example of graph node after range checking is enabled:
+ * @cliexstart{show vlib graph ip4-rx-urpf-loose}
+ * Name Next Previous
+ * ip4-rx-urpf-loose ip4-drop [0] ip4-input-no-checksum
+ * ip4-source-and-port-range- ip4-input
+ * @cliexend
+ *
+ * Example of how to display the feature enabed on an interface:
+ * @cliexstart{show ip interface features GigabitEthernet2/0/0}
+ * IP feature paths configured on GigabitEthernet2/0/0...
+ *
+ * ipv4 unicast:
+ * ip4-rx-urpf-loose
+ * ip4-lookup
+ *
+ * ipv4 multicast:
+ * ip4-lookup-multicast
+ *
+ * ipv4 multicast:
+ * interface-output
+ *
+ * ipv6 unicast:
+ * ip6-lookup
+ *
+ * ipv6 multicast:
+ * ip6-lookup
+ *
+ * ipv6 multicast:
+ * interface-output
+ * @cliexend
+ *
+ * Example of how to disable unicast source checking on an interface:
+ * @cliexcmd{set urpf ip4 off GigabitEthernet2/0/0}
+ * @endparblock
+?*/
+/* *INDENT-OFF* */
+VLIB_CLI_COMMAND (set_interface_ip_source_check_command, static) = {
+ .path = "set urpf",
+ .function = urpf_cli_update,
+ .short_help = "set urpf [ip4|ip6] [rx|tx] [off|strict|loose] <INTERFACE>",
+};
+/* *INDENT-ON* */
+
+static clib_error_t *
+urpf_cli_accept (vlib_main_t * vm,
+ unformat_input_t * input, vlib_cli_command_t * cmd)
+{
+ unformat_input_t _line_input, *line_input = &_line_input;
+ clib_error_t *error = NULL;
+ fib_prefix_t fpfx;
+ ip_prefix_t pfx;
+ u32 table_id, is_add, fib_index;
+
+ is_add = 1;
+ table_id = 0;
+
+ /* Get a line of input. */
+ if (!unformat_user (input, unformat_line_input, line_input))
+ return 0;
+
+ while (unformat_check_input (line_input) != UNFORMAT_END_OF_INPUT)
+ {
+ if (unformat (line_input, "table %d", &table_id))
+ ;
+ else if (unformat (line_input, "del"))
+ is_add = 0;
+ else if (unformat (line_input, "add"))
+ is_add = 1;
+ else if (unformat (line_input, "%U", unformat_ip_prefix, &pfx))
+ ;
+ else
+ {
+ error = unformat_parse_error (line_input);
+ goto done;
+ }
+ }
+
+ ip_prefix_to_fib_prefix (&pfx, &fpfx);
+
+ fib_index = fib_table_find (fpfx.fp_proto, table_id);
+
+ if (~0 == fib_index)
+ {
+ error = clib_error_return (0, "Nonexistent table id %d", table_id);
+ goto done;
+ }
+
+ if (is_add)
+ fib_table_entry_special_add (fib_index,
+ &fpfx,
+ FIB_SOURCE_URPF_EXEMPT, FIB_ENTRY_FLAG_DROP);
+ else
+ fib_table_entry_special_remove (fib_index, &fpfx, FIB_SOURCE_URPF_EXEMPT);
+
+done:
+ unformat_free (line_input);
+
+ return (error);
+}
+
+/*?
+ * Add an exemption for a prefix to pass the Unicast Reverse Path
+ * Forwarding (uRPF) loose check. This is for testing purposes only.
+ * If the '<em>table</em>' is not enter it is defaulted to 0. Default
+ * is to '<em>add</em>'. VPP always performs a loose uRPF check for
+ * for-us traffic.
+ *
+ * @cliexpar
+ * Example of how to add a uRPF exception to a FIB table to pass the
+ * loose RPF tests:
+ * @cliexcmd{set urpf-accept table 7 10.0.0.0/8 add}
+?*/
+/* *INDENT-OFF* */
+VLIB_CLI_COMMAND (urpf_accept_command, static) = {
+ .path = "set urpf-accept",
+ .function = urpf_cli_accept,
+ .short_help = "urpf-accept [table <table-id>] [add|del] <PREFIX>",
+};
+/* *INDENT-ON* */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
Code Review / vpp.git / blobdiff