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-rw-r--r--src/vnet/bfd/bfd_main.c628
1 files changed, 568 insertions, 60 deletions
diff --git a/src/vnet/bfd/bfd_main.c b/src/vnet/bfd/bfd_main.c
index 7e1a2ef24a7..8f2fae2b795 100644
--- a/src/vnet/bfd/bfd_main.c
+++ b/src/vnet/bfd/bfd_main.c
@@ -25,6 +25,9 @@
#include <vnet/bfd/bfd_debug.h>
#include <vnet/bfd/bfd_protocol.h>
#include <vnet/bfd/bfd_main.h>
+#if WITH_LIBSSL > 0
+#include <openssl/sha.h>
+#endif
static u64
bfd_us_to_clocks (bfd_main_t * bm, u64 us)
@@ -41,6 +44,23 @@ static u32 bfd_node_index_by_transport[] = {
#undef F
};
+static u8 *
+format_bfd_auth_key (u8 * s, va_list * args)
+{
+ const bfd_auth_key_t *key = va_arg (*args, bfd_auth_key_t *);
+ if (key)
+ {
+ s = format (s, "{auth-type=%u:%s, conf-key-id=%u, use-count=%u}, ",
+ key->auth_type, bfd_auth_type_str (key->auth_type),
+ key->conf_key_id, key->use_count);
+ }
+ else
+ {
+ s = format (s, "{none}");
+ }
+ return s;
+}
+
/*
* We actually send all bfd pkts to the "error" node after scanning
* them, so the graph node has only one next-index. The "error-drop"
@@ -67,6 +87,9 @@ bfd_set_defaults (bfd_main_t * bm, bfd_session_t * bs)
bs->desired_min_tx_clocks = bfd_us_to_clocks (bm, bs->desired_min_tx_us);
bs->remote_min_rx_us = 1;
bs->remote_demand = 0;
+ bs->auth.remote_seq_number = 0;
+ bs->auth.remote_seq_number_known = 0;
+ bs->auth.local_seq_number = random_u32 (&bm->random_seed);
}
static void
@@ -288,7 +311,7 @@ bfd_del_session (uword bs_idx)
else
{
BFD_ERR ("no such session");
- return VNET_API_ERROR_BFD_NOENT;
+ return VNET_API_ERROR_BFD_ENOENT;
}
return 0;
}
@@ -319,16 +342,10 @@ bfd_state_string (bfd_state_e state)
#undef F
}
-vnet_api_error_t
-bfd_session_set_flags (u32 bs_idx, u8 admin_up_down)
+void
+bfd_session_set_flags (bfd_session_t * bs, u8 admin_up_down)
{
bfd_main_t *bm = &bfd_main;
- if (pool_is_free_index (bm->sessions, bs_idx))
- {
- BFD_ERR ("invalid bs_idx=%u", bs_idx);
- return VNET_API_ERROR_BFD_NOENT;
- }
- bfd_session_t *bs = pool_elt_at_index (bm->sessions, bs_idx);
if (admin_up_down)
{
bfd_set_state (bm, bs, BFD_STATE_down, 0);
@@ -338,7 +355,6 @@ bfd_session_set_flags (u32 bs_idx, u8 admin_up_down)
bfd_set_diag (bs, BFD_DIAG_CODE_neighbor_sig_down);
bfd_set_state (bm, bs, BFD_STATE_admin_down, 0);
}
- return 0;
}
u8 *
@@ -351,8 +367,8 @@ bfd_input_format_trace (u8 * s, va_list * args)
if (t->len > STRUCT_SIZE_OF (bfd_pkt_t, head))
{
s = format (s, "BFD v%u, diag=%u(%s), state=%u(%s),\n"
- " flags=(P:%u, F:%u, C:%u, A:%u, D:%u, M:%u), detect_mult=%u, "
- "length=%u\n",
+ " flags=(P:%u, F:%u, C:%u, A:%u, D:%u, M:%u), "
+ "detect_mult=%u, length=%u\n",
bfd_pkt_get_version (pkt), bfd_pkt_get_diag_code (pkt),
bfd_diag_code_string (bfd_pkt_get_diag_code (pkt)),
bfd_pkt_get_state (pkt),
@@ -362,8 +378,8 @@ bfd_input_format_trace (u8 * s, va_list * args)
bfd_pkt_get_auth_present (pkt), bfd_pkt_get_demand (pkt),
bfd_pkt_get_multipoint (pkt), pkt->head.detect_mult,
pkt->head.length);
- if (t->len >= sizeof (bfd_pkt_t)
- && pkt->head.length >= sizeof (bfd_pkt_t))
+ if (t->len >= sizeof (bfd_pkt_t) &&
+ pkt->head.length >= sizeof (bfd_pkt_t))
{
s = format (s, " my discriminator: %u\n", pkt->my_disc);
s = format (s, " your discriminator: %u\n", pkt->your_disc);
@@ -430,8 +446,7 @@ bfd_add_transport_layer (vlib_main_t * vm, vlib_buffer_t * b,
}
static vlib_buffer_t *
-bfd_create_frame (vlib_main_t * vm, vlib_node_runtime_t * rt,
- bfd_session_t * bs)
+bfd_create_frame_to_next_node (vlib_main_t * vm, bfd_session_t * bs)
{
u32 bi;
if (vlib_buffer_alloc (vm, &bi, 1) != 1)
@@ -454,13 +469,82 @@ bfd_create_frame (vlib_main_t * vm, vlib_node_runtime_t * rt,
return b;
}
+#if WITH_LIBSSL > 0
+static void
+bfd_add_sha1_auth_section (vlib_buffer_t * b, bfd_session_t * bs)
+{
+ bfd_pkt_with_sha1_auth_t *pkt = vlib_buffer_get_current (b);
+ bfd_auth_sha1_t *auth = &pkt->sha1_auth;
+ b->current_length += sizeof (*auth);
+ pkt->pkt.head.length += sizeof (*auth);
+ bfd_pkt_set_auth_present (&pkt->pkt);
+ memset (auth, 0, sizeof (*auth));
+ auth->type_len.type = bs->auth.curr_key->auth_type;
+ /*
+ * only meticulous authentication types require incrementing seq number
+ * for every message, but doing so doesn't violate the RFC
+ */
+ ++bs->auth.local_seq_number;
+ auth->type_len.len = sizeof (bfd_auth_sha1_t);
+ auth->key_id = bs->auth.curr_bfd_key_id;
+ auth->seq_num = clib_host_to_net_u32 (bs->auth.local_seq_number);
+ /*
+ * first copy the password into the packet, then calculate the hash
+ * and finally replace the password with the calculated hash
+ */
+ clib_memcpy (auth->hash, bs->auth.curr_key->key,
+ sizeof (bs->auth.curr_key->key));
+ unsigned char hash[sizeof (auth->hash)];
+ SHA1 ((unsigned char *) pkt, sizeof (*pkt), hash);
+ BFD_DBG ("hashing: %U", format_hex_bytes, pkt, sizeof (*pkt));
+ clib_memcpy (auth->hash, hash, sizeof (hash));
+#endif
+}
+
+static void
+bfd_add_auth_section (vlib_buffer_t * b, bfd_session_t * bs)
+{
+ if (bs->auth.curr_key)
+ {
+ const bfd_auth_type_e auth_type = bs->auth.curr_key->auth_type;
+ switch (auth_type)
+ {
+ case BFD_AUTH_TYPE_reserved:
+ /* fallthrough */
+ case BFD_AUTH_TYPE_simple_password:
+ /* fallthrough */
+ case BFD_AUTH_TYPE_keyed_md5:
+ /* fallthrough */
+ case BFD_AUTH_TYPE_meticulous_keyed_md5:
+ clib_warning ("Internal error, unexpected BFD auth type '%d'",
+ auth_type);
+ break;
+#if WITH_LIBSSL > 0
+ case BFD_AUTH_TYPE_keyed_sha1:
+ /* fallthrough */
+ case BFD_AUTH_TYPE_meticulous_keyed_sha1:
+ bfd_add_sha1_auth_section (b, bs);
+ break;
+#else
+ case BFD_AUTH_TYPE_keyed_sha1:
+ /* fallthrough */
+ case BFD_AUTH_TYPE_meticulous_keyed_sha1:
+ clib_warning ("Internal error, unexpected BFD auth type '%d'",
+ auth_type);
+ break;
+#endif
+ }
+ }
+}
+
static void
bfd_init_control_frame (vlib_buffer_t * b, bfd_session_t * bs)
{
bfd_pkt_t *pkt = vlib_buffer_get_current (b);
- const u32 bfd_length = 24;
- memset (pkt, 0, sizeof (*pkt));
+ u32 bfd_length = 0;
+ bfd_length = sizeof (bfd_pkt_t);
+ memset (pkt, 0, sizeof (*pkt));
bfd_pkt_set_version (pkt, 1);
bfd_pkt_set_diag_code (pkt, bs->local_diag);
bfd_pkt_set_state (pkt, bs->local_state);
@@ -477,6 +561,7 @@ bfd_init_control_frame (vlib_buffer_t * b, bfd_session_t * bs)
pkt->req_min_rx = clib_host_to_net_u32 (bs->required_min_rx_us);
pkt->req_min_echo_rx = clib_host_to_net_u32 (bs->required_min_echo_rx_us);
b->current_length = bfd_length;
+ bfd_add_auth_section (b, bs);
}
static void
@@ -502,7 +587,7 @@ bfd_send_periodic (vlib_main_t * vm, vlib_node_runtime_t * rt,
if (now + bm->wheel_inaccuracy >= bs->tx_timeout_clocks)
{
BFD_DBG ("Send periodic control frame for bs_idx=%lu", bs->bs_idx);
- vlib_buffer_t *b = bfd_create_frame (vm, rt, bs);
+ vlib_buffer_t *b = bfd_create_frame_to_next_node (vm, bs);
if (!b)
{
return;
@@ -522,7 +607,8 @@ bfd_send_periodic (vlib_main_t * vm, vlib_node_runtime_t * rt,
}
void
-bfd_send_final (vlib_main_t * vm, vlib_buffer_t * b, bfd_session_t * bs)
+bfd_init_final_control_frame (vlib_main_t * vm, vlib_buffer_t * b,
+ bfd_session_t * bs)
{
BFD_DBG ("Send final control frame for bs_idx=%lu", bs->bs_idx);
bfd_init_control_frame (b, bs);
@@ -624,13 +710,17 @@ bfd_process (vlib_main_t * vm, vlib_node_runtime_t * rt, vlib_frame_t * f)
* each event or timeout */
break;
case BFD_EVENT_NEW_SESSION:
- do
+ if (!pool_is_free_index (bm->sessions, *event_data))
{
bfd_session_t *bs =
pool_elt_at_index (bm->sessions, *event_data);
bfd_send_periodic (vm, rt, bm, bs, now, 1);
}
- while (0);
+ else
+ {
+ BFD_DBG ("Ignoring event for non-existent session index %u",
+ (u32) * event_data);
+ }
break;
default:
clib_warning ("BUG: event type 0x%wx", event_type);
@@ -710,22 +800,25 @@ VNET_HW_INTERFACE_LINK_UP_DOWN_FUNCTION (bfd_hw_interface_up_down);
static clib_error_t *
bfd_main_init (vlib_main_t * vm)
{
+#if BFD_DEBUG
+ setbuf (stdout, NULL);
+#endif
bfd_main_t *bm = &bfd_main;
bm->random_seed = random_default_seed ();
bm->vlib_main = vm;
bm->vnet_main = vnet_get_main ();
memset (&bm->wheel, 0, sizeof (bm->wheel));
- bm->cpu_cps = 2590000000; // vm->clib_time.clocks_per_second;
+ bm->cpu_cps = vm->clib_time.clocks_per_second;
BFD_DBG ("cps is %.2f", bm->cpu_cps);
const u64 now = clib_cpu_time_now ();
timing_wheel_init (&bm->wheel, now, bm->cpu_cps);
bm->wheel_inaccuracy = 2 << bm->wheel.log2_clocks_per_bin;
vlib_node_t *node = NULL;
-#define F(t, n) \
- node = vlib_get_node_by_name (vm, (u8 *)n); \
- bfd_node_index_by_transport[BFD_TRANSPORT_##t] = node->index;\
- BFD_DBG("node '%s' has index %u", n, node->index);
+#define F(t, n) \
+ node = vlib_get_node_by_name (vm, (u8 *)n); \
+ bfd_node_index_by_transport[BFD_TRANSPORT_##t] = node->index; \
+ BFD_DBG ("node '%s' has index %u", n, node->index);
foreach_bfd_transport (F);
#undef F
return 0;
@@ -750,6 +843,14 @@ bfd_get_session (bfd_main_t * bm, bfd_transport_t t)
void
bfd_put_session (bfd_main_t * bm, bfd_session_t * bs)
{
+ if (bs->auth.curr_key)
+ {
+ --bs->auth.curr_key->use_count;
+ }
+ if (bs->auth.next_key)
+ {
+ --bs->auth.next_key->use_count;
+ }
hash_unset (bm->session_by_disc, bs->local_discr);
pool_put (bm->sessions, bs);
}
@@ -793,7 +894,7 @@ bfd_verify_pkt_common (const bfd_pkt_t * pkt)
}
if (pkt->head.length < sizeof (bfd_pkt_t) ||
(bfd_pkt_get_auth_present (pkt) &&
- pkt->head.length < sizeof (bfd_pkt_with_auth_t)))
+ pkt->head.length < sizeof (bfd_pkt_with_common_auth_t)))
{
BFD_ERR ("BFD verification failed - unexpected length: '%d' (auth "
"present: %d)",
@@ -831,6 +932,226 @@ bfd_verify_pkt_common (const bfd_pkt_t * pkt)
return 1;
}
+static void
+bfd_session_switch_auth_to_next (bfd_session_t * bs)
+{
+ BFD_DBG ("Switching authentication key from %U to %U for bs_idx=%u",
+ format_bfd_auth_key, bs->auth.curr_key, format_bfd_auth_key,
+ bs->auth.next_key, bs->bs_idx);
+ bs->auth.is_delayed = 0;
+ if (bs->auth.curr_key)
+ {
+ --bs->auth.curr_key->use_count;
+ }
+ bs->auth.curr_key = bs->auth.next_key;
+ bs->auth.next_key = NULL;
+ bs->auth.curr_bfd_key_id = bs->auth.next_bfd_key_id;
+}
+
+static int
+bfd_auth_type_is_meticulous (bfd_auth_type_e auth_type)
+{
+ if (BFD_AUTH_TYPE_meticulous_keyed_md5 == auth_type ||
+ BFD_AUTH_TYPE_meticulous_keyed_sha1 == auth_type)
+ {
+ return 1;
+ }
+ return 0;
+}
+
+static int
+bfd_verify_pkt_auth_seq_num (bfd_session_t * bs,
+ u32 received_seq_num, int is_meticulous)
+{
+ /*
+ * RFC 5880 6.8.1:
+ *
+ * This variable MUST be set to zero after no packets have been
+ * received on this session for at least twice the Detection Time.
+ */
+ u64 now = clib_cpu_time_now ();
+ if (now - bs->last_rx_clocks > bs->detection_time_clocks * 2)
+ {
+ BFD_DBG ("BFD peer unresponsive for %lu clocks, which is > 2 * "
+ "detection_time=%u clocks, resetting remote_seq_number_known "
+ "flag",
+ now - bs->last_rx_clocks, bs->detection_time_clocks * 2);
+ bs->auth.remote_seq_number_known = 0;
+ }
+ if (bs->auth.remote_seq_number_known)
+ {
+ /* remote sequence number is known, verify its validity */
+ const u32 max_u32 = 0xffffffff;
+ /* the calculation might wrap, account for the special case... */
+ if (bs->auth.remote_seq_number > max_u32 - 3 * bs->local_detect_mult)
+ {
+ /*
+ * special case
+ *
+ * x y z
+ * |----------+----------------------------+-----------|
+ * 0 ^ ^ 0xffffffff
+ * | remote_seq_num------+
+ * |
+ * +-----(remote_seq_num + 3*detect_mult) % * 0xffffffff
+ *
+ * x + y + z = 0xffffffff
+ * x + z = 3 * detect_mult
+ */
+ const u32 z = max_u32 - bs->auth.remote_seq_number;
+ const u32 x = 3 * bs->local_detect_mult - z;
+ if (received_seq_num > x &&
+ received_seq_num < bs->auth.remote_seq_number + is_meticulous)
+ {
+ BFD_ERR
+ ("Recvd sequence number=%u out of ranges <0, %u>, <%u, %u>",
+ received_seq_num, x,
+ bs->auth.remote_seq_number + is_meticulous, max_u32);
+ return 0;
+ }
+ }
+ else
+ {
+ /* regular case */
+ const u32 min = bs->auth.remote_seq_number + is_meticulous;
+ const u32 max =
+ bs->auth.remote_seq_number + 3 * bs->local_detect_mult;
+ if (received_seq_num < min || received_seq_num > max)
+ {
+ BFD_ERR ("Recvd sequence number=%u out of range <%u, %u>",
+ received_seq_num, min, max);
+ return 0;
+ }
+ }
+ }
+ return 1;
+}
+
+static int
+bfd_verify_pkt_auth_key_sha1 (const bfd_pkt_t * pkt, u32 pkt_size,
+ bfd_session_t * bs, u8 bfd_key_id,
+ bfd_auth_key_t * auth_key)
+{
+ ASSERT (auth_key->auth_type == BFD_AUTH_TYPE_keyed_sha1 ||
+ auth_key->auth_type == BFD_AUTH_TYPE_meticulous_keyed_sha1);
+
+ u8 result[SHA_DIGEST_LENGTH];
+ bfd_pkt_with_common_auth_t *with_common = (void *) pkt;
+ if (pkt_size < sizeof (*with_common))
+ {
+ BFD_ERR ("Packet size too small to hold authentication common header");
+ return 0;
+ }
+ if (with_common->common_auth.type != auth_key->auth_type)
+ {
+ BFD_ERR ("BFD auth type mismatch, packet auth=%d:%s doesn't match "
+ "in-use auth=%d:%s",
+ with_common->common_auth.type,
+ bfd_auth_type_str (with_common->common_auth.type),
+ auth_key->auth_type, bfd_auth_type_str (auth_key->auth_type));
+ return 0;
+ }
+ bfd_pkt_with_sha1_auth_t *with_sha1 = (void *) pkt;
+ if (pkt_size < sizeof (*with_sha1) ||
+ with_sha1->sha1_auth.type_len.len < sizeof (with_sha1->sha1_auth))
+ {
+ BFD_ERR
+ ("BFD size mismatch, payload size=%u, expected=%u, auth_len=%u, "
+ "expected=%u", pkt_size, sizeof (*with_sha1),
+ with_sha1->sha1_auth.type_len.len, sizeof (with_sha1->sha1_auth));
+ return 0;
+ }
+ if (with_sha1->sha1_auth.key_id != bfd_key_id)
+ {
+ BFD_ERR
+ ("BFD key ID mismatch, packet key ID=%u doesn't match key ID=%u%s",
+ with_sha1->sha1_auth.key_id, bfd_key_id,
+ bs->
+ auth.is_delayed ? " (but a delayed auth change is scheduled)" : "");
+ return 0;
+ }
+ SHA_CTX ctx;
+ if (!SHA1_Init (&ctx))
+ {
+ BFD_ERR ("SHA1_Init failed");
+ return 0;
+ }
+ /* ignore last 20 bytes - use the actual key data instead pkt data */
+ if (!SHA1_Update (&ctx, with_sha1,
+ sizeof (*with_sha1) - sizeof (with_sha1->sha1_auth.hash)))
+ {
+ BFD_ERR ("SHA1_Update failed");
+ return 0;
+ }
+ if (!SHA1_Update (&ctx, auth_key->key, sizeof (auth_key->key)))
+ {
+ BFD_ERR ("SHA1_Update failed");
+ return 0;
+ }
+ if (!SHA1_Final (result, &ctx))
+ {
+ BFD_ERR ("SHA1_Final failed");
+ return 0;
+ }
+ if (0 == memcmp (result, with_sha1->sha1_auth.hash, SHA_DIGEST_LENGTH))
+ {
+ return 1;
+ }
+ BFD_ERR ("SHA1 hash: %U doesn't match the expected value: %U",
+ format_hex_bytes, with_sha1->sha1_auth.hash, SHA_DIGEST_LENGTH,
+ format_hex_bytes, result, SHA_DIGEST_LENGTH);
+ return 0;
+}
+
+static int
+bfd_verify_pkt_auth_key (const bfd_pkt_t * pkt, u32 pkt_size,
+ bfd_session_t * bs, u8 bfd_key_id,
+ bfd_auth_key_t * auth_key)
+{
+ switch (auth_key->auth_type)
+ {
+ case BFD_AUTH_TYPE_reserved:
+ clib_warning ("Internal error, unexpected auth_type=%d:%s",
+ auth_key->auth_type,
+ bfd_auth_type_str (auth_key->auth_type));
+ return 0;
+ case BFD_AUTH_TYPE_simple_password:
+ clib_warning
+ ("Internal error, not implemented, unexpected auth_type=%d:%s",
+ auth_key->auth_type, bfd_auth_type_str (auth_key->auth_type));
+ return 0;
+ case BFD_AUTH_TYPE_keyed_md5:
+ /* fallthrough */
+ case BFD_AUTH_TYPE_meticulous_keyed_md5:
+ clib_warning
+ ("Internal error, not implemented, unexpected auth_type=%d:%s",
+ auth_key->auth_type, bfd_auth_type_str (auth_key->auth_type));
+ return 0;
+ case BFD_AUTH_TYPE_keyed_sha1:
+ /* fallthrough */
+ case BFD_AUTH_TYPE_meticulous_keyed_sha1:
+#if WITH_LIBSSL > 0
+ do
+ {
+ const u32 seq_num = clib_net_to_host_u32 (((bfd_pkt_with_sha1_auth_t
+ *) pkt)->
+ sha1_auth.seq_num);
+ return bfd_verify_pkt_auth_seq_num (bs, seq_num,
+ bfd_auth_type_is_meticulous
+ (auth_key->auth_type))
+ && bfd_verify_pkt_auth_key_sha1 (pkt, pkt_size, bs, bfd_key_id,
+ auth_key);
+ }
+ while (0);
+#else
+ clib_warning
+ ("Internal error, attempt to use SHA1 without SSL support");
+ return 0;
+#endif
+ }
+ return 0;
+}
+
/**
* @brief verify bfd packet - authentication
*
@@ -839,30 +1160,81 @@ bfd_verify_pkt_common (const bfd_pkt_t * pkt)
* @return 1 if bfd packet is valid
*/
int
-bfd_verify_pkt_session (const bfd_pkt_t * pkt, u16 pkt_size,
- const bfd_session_t * bs)
+bfd_verify_pkt_auth (const bfd_pkt_t * pkt, u16 pkt_size, bfd_session_t * bs)
{
- const bfd_pkt_with_auth_t *with_auth = (bfd_pkt_with_auth_t *) pkt;
- if (!bfd_pkt_get_auth_present (pkt))
+ if (bfd_pkt_get_auth_present (pkt))
{
- if (pkt_size > sizeof (*pkt))
+ /* authentication present in packet */
+ if (!bs->auth.curr_key)
{
- BFD_ERR ("BFD verification failed - unexpected packet size '%d' "
- "(auth not present)", pkt_size);
- return 0;
+ /* currently not using authentication - can we turn it on? */
+ if (bs->auth.is_delayed && bs->auth.next_key)
+ {
+ /* yes, switch is scheduled - make sure the auth is valid */
+ if (bfd_verify_pkt_auth_key (pkt, pkt_size, bs,
+ bs->auth.next_bfd_key_id,
+ bs->auth.next_key))
+ {
+ /* auth matches next key, do the switch, packet is valid */
+ bfd_session_switch_auth_to_next (bs);
+ return 1;
+ }
+ }
+ }
+ else
+ {
+ /* yes, using authentication, verify the key */
+ if (bfd_verify_pkt_auth_key (pkt, pkt_size, bs,
+ bs->auth.curr_bfd_key_id,
+ bs->auth.curr_key))
+ {
+ /* verification passed, packet is valid */
+ return 1;
+ }
+ else
+ {
+ /* verification failed - but maybe we need to switch key */
+ if (bs->auth.is_delayed && bs->auth.next_key)
+ {
+ /* delayed switch present, verify if that key works */
+ if (bfd_verify_pkt_auth_key (pkt, pkt_size, bs,
+ bs->auth.next_bfd_key_id,
+ bs->auth.next_key))
+ {
+ /* auth matches next key, switch key, packet is valid */
+ bfd_session_switch_auth_to_next (bs);
+ return 1;
+ }
+ }
+ }
}
}
else
{
- if (!with_auth->auth.type)
+ /* authentication in packet not present */
+ if (pkt_size > sizeof (*pkt))
{
- BFD_ERR ("BFD verification failed - unexpected auth type: '%d'",
- with_auth->auth.type);
+ BFD_ERR ("BFD verification failed - unexpected packet size '%d' "
+ "(auth not present)", pkt_size);
return 0;
}
- /* TODO FIXME - implement the actual verification */
+ if (bs->auth.curr_key)
+ {
+ /* currently authenticating - could we turn it off? */
+ if (bs->auth.is_delayed && !bs->auth.next_key)
+ {
+ /* yes, delayed switch to NULL key is scheduled */
+ bfd_session_switch_auth_to_next (bs);
+ return 1;
+ }
+ }
+ else
+ {
+ /* no auth in packet, no auth in use - packet is valid */
+ return 1;
+ }
}
- return 1;
+ return 0;
}
void
@@ -879,6 +1251,38 @@ bfd_consume_pkt (bfd_main_t * bm, const bfd_pkt_t * pkt, u32 bs_idx)
bs->remote_demand = bfd_pkt_get_demand (pkt);
u64 now = clib_cpu_time_now ();
bs->last_rx_clocks = now;
+ if (bfd_pkt_get_auth_present (pkt))
+ {
+ bfd_auth_type_e auth_type =
+ ((bfd_pkt_with_common_auth_t *) (pkt))->common_auth.type;
+ switch (auth_type)
+ {
+ case BFD_AUTH_TYPE_reserved:
+ /* fallthrough */
+ case BFD_AUTH_TYPE_simple_password:
+ /* fallthrough */
+ case BFD_AUTH_TYPE_keyed_md5:
+ /* fallthrough */
+ case BFD_AUTH_TYPE_meticulous_keyed_md5:
+ clib_warning ("Internal error, unexpected auth_type=%d:%s",
+ auth_type, bfd_auth_type_str (auth_type));
+ break;
+ case BFD_AUTH_TYPE_keyed_sha1:
+ /* fallthrough */
+ case BFD_AUTH_TYPE_meticulous_keyed_sha1:
+ do
+ {
+ bfd_pkt_with_sha1_auth_t *with_sha1 =
+ (bfd_pkt_with_sha1_auth_t *) pkt;
+ bs->auth.remote_seq_number =
+ clib_net_to_host_u32 (with_sha1->sha1_auth.seq_num);
+ bs->auth.remote_seq_number_known = 1;
+ BFD_DBG ("Received sequence number %u",
+ bs->auth.remote_seq_number);
+ }
+ while (0);
+ }
+ }
bs->remote_desired_min_tx_us = clib_net_to_host_u32 (pkt->des_min_tx);
bs->remote_detect_mult = pkt->head.detect_mult;
bfd_set_remote_required_min_rx (bm, bs, now,
@@ -933,25 +1337,129 @@ u8 *
format_bfd_session (u8 * s, va_list * args)
{
const bfd_session_t *bs = va_arg (*args, bfd_session_t *);
- return format (s, "BFD(%u): bfd.SessionState=%s, "
- "bfd.RemoteSessionState=%s, "
- "bfd.LocalDiscr=%u, "
- "bfd.RemoteDiscr=%u, "
- "bfd.LocalDiag=%s, "
- "bfd.DesiredMinTxInterval=%u, "
- "bfd.RequiredMinRxInterval=%u, "
- "bfd.RequiredMinEchoRxInterval=%u, "
- "bfd.RemoteMinRxInterval=%u, "
- "bfd.DemandMode=%s, "
- "bfd.RemoteDemandMode=%s, "
- "bfd.DetectMult=%u, ",
- bs->bs_idx, bfd_state_string (bs->local_state),
- bfd_state_string (bs->remote_state), bs->local_discr,
- bs->remote_discr, bfd_diag_code_string (bs->local_diag),
- bs->desired_min_tx_us, bs->required_min_rx_us,
- bs->required_min_echo_rx_us, bs->remote_min_rx_us,
- (bs->local_demand ? "yes" : "no"),
- (bs->remote_demand ? "yes" : "no"), bs->local_detect_mult);
+ s = format (s, "BFD(%u): bfd.SessionState=%s, "
+ "bfd.RemoteSessionState=%s, "
+ "bfd.LocalDiscr=%u, "
+ "bfd.RemoteDiscr=%u, "
+ "bfd.LocalDiag=%s, "
+ "bfd.DesiredMinTxInterval=%u, "
+ "bfd.RequiredMinRxInterval=%u, "
+ "bfd.RequiredMinEchoRxInterval=%u, "
+ "bfd.RemoteMinRxInterval=%u, "
+ "bfd.DemandMode=%s, "
+ "bfd.RemoteDemandMode=%s, "
+ "bfd.DetectMult=%u, "
+ "Auth: {local-seq-num=%u, "
+ "remote-seq-num=%u, "
+ "is-delayed=%s, "
+ "curr-key=%U, "
+ "next-key=%U}",
+ bs->bs_idx, bfd_state_string (bs->local_state),
+ bfd_state_string (bs->remote_state), bs->local_discr,
+ bs->remote_discr, bfd_diag_code_string (bs->local_diag),
+ bs->desired_min_tx_us, bs->required_min_rx_us,
+ bs->required_min_echo_rx_us, bs->remote_min_rx_us,
+ (bs->local_demand ? "yes" : "no"),
+ (bs->remote_demand ? "yes" : "no"), bs->local_detect_mult,
+ bs->auth.local_seq_number, bs->auth.remote_seq_number,
+ (bs->auth.is_delayed ? "yes" : "no"), format_bfd_auth_key,
+ bs->auth.curr_key, format_bfd_auth_key, bs->auth.next_key);
+ return s;
+}
+
+unsigned
+bfd_auth_type_supported (bfd_auth_type_e auth_type)
+{
+ if (auth_type == BFD_AUTH_TYPE_keyed_sha1 ||
+ auth_type == BFD_AUTH_TYPE_meticulous_keyed_sha1)
+ {
+ return 1;
+ }
+ return 0;
+}
+
+vnet_api_error_t
+bfd_auth_activate (bfd_session_t * bs, u32 conf_key_id,
+ u8 bfd_key_id, u8 is_delayed)
+{
+ bfd_main_t *bm = &bfd_main;
+ const uword *key_idx_p =
+ hash_get (bm->auth_key_by_conf_key_id, conf_key_id);
+ if (!key_idx_p)
+ {
+ clib_warning ("Authentication key with config ID %u doesn't exist)",
+ conf_key_id);
+ return VNET_API_ERROR_BFD_ENOENT;
+ }
+ const uword key_idx = *key_idx_p;
+ bfd_auth_key_t *key = pool_elt_at_index (bm->auth_keys, key_idx);
+ if (is_delayed)
+ {
+ if (bs->auth.next_key == key)
+ {
+ /* already using this key, no changes required */
+ return 0;
+ }
+ bs->auth.next_key = key;
+ bs->auth.next_bfd_key_id = bfd_key_id;
+ bs->auth.is_delayed = 1;
+ }
+ else
+ {
+ if (bs->auth.curr_key == key)
+ {
+ /* already using this key, no changes required */
+ return 0;
+ }
+ if (bs->auth.curr_key)
+ {
+ --bs->auth.curr_key->use_count;
+ }
+ bs->auth.curr_key = key;
+ bs->auth.curr_bfd_key_id = bfd_key_id;
+ bs->auth.is_delayed = 0;
+ }
+ ++key->use_count;
+ BFD_DBG ("Session auth modified: %U", format_bfd_session, bs);
+ return 0;
+}
+
+vnet_api_error_t
+bfd_auth_deactivate (bfd_session_t * bs, u8 is_delayed)
+{
+#if WITH_LIBSSL > 0
+ if (!is_delayed)
+ {
+ /* not delayed - deactivate the current key right now */
+ if (bs->auth.curr_key)
+ {
+ --bs->auth.curr_key->use_count;
+ bs->auth.curr_key = NULL;
+ }
+ bs->auth.is_delayed = 0;
+ }
+ else
+ {
+ /* delayed - mark as so */
+ bs->auth.is_delayed = 1;
+ }
+ /*
+ * clear the next key unconditionally - either the auth change is not delayed
+ * in which case the caller expects the session to not use authentication
+ * from this point forward, or it is delayed, in which case the next_key
+ * needs to be set to NULL to make it so in the future
+ */
+ if (bs->auth.next_key)
+ {
+ --bs->auth.next_key->use_count;
+ bs->auth.next_key = NULL;
+ }
+ BFD_DBG ("Session auth modified: %U", format_bfd_session, bs);
+ return 0;
+#else
+ clib_warning ("SSL missing, cannot deactivate BFD authentication");
+ return VNET_API_ERROR_BFD_NOTSUPP;
+#endif
}
bfd_main_t bfd_main;