--- /dev/null
+/*
+ * Copyright (c) 2008, 2009, 2010, 2011 Nicira Networks.
+ *
+ * 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.
+ */
+
+/* Based on sample implementation in 802.1D-1998. Above copyright and license
+ * applies to all modifications. */
+
+#include <config.h>
+
+#include "stp.h"
+#include <sys/types.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <assert.h>
+#include <inttypes.h>
+#include <stdlib.h>
+#include "byte-order.h"
+#include "ofpbuf.h"
+#include "packets.h"
+#include "util.h"
+#include "vlog.h"
+
+VLOG_DEFINE_THIS_MODULE(stp);
+
+#define STP_PROTOCOL_ID 0x0000
+#define STP_PROTOCOL_VERSION 0x00
+#define STP_TYPE_CONFIG 0x00
+#define STP_TYPE_TCN 0x80
+
+struct stp_bpdu_header {
+ ovs_be16 protocol_id; /* STP_PROTOCOL_ID. */
+ uint8_t protocol_version; /* STP_PROTOCOL_VERSION. */
+ uint8_t bpdu_type; /* One of STP_TYPE_*. */
+} __attribute__((packed));
+BUILD_ASSERT_DECL(sizeof(struct stp_bpdu_header) == 4);
+
+enum stp_config_bpdu_flags {
+ STP_CONFIG_TOPOLOGY_CHANGE_ACK = 0x80,
+ STP_CONFIG_TOPOLOGY_CHANGE = 0x01
+};
+
+struct stp_config_bpdu {
+ struct stp_bpdu_header header; /* Type STP_TYPE_CONFIG. */
+ uint8_t flags; /* STP_CONFIG_* flags. */
+ ovs_be64 root_id; /* 8.5.1.1: Bridge believed to be root. */
+ ovs_be32 root_path_cost; /* 8.5.1.2: Cost of path to root. */
+ ovs_be64 bridge_id; /* 8.5.1.3: ID of transmitting bridge. */
+ ovs_be16 port_id; /* 8.5.1.4: Port transmitting the BPDU. */
+ ovs_be16 message_age; /* 8.5.1.5: Age of BPDU at tx time. */
+ ovs_be16 max_age; /* 8.5.1.6: Timeout for received data. */
+ ovs_be16 hello_time; /* 8.5.1.7: Time between BPDU generation. */
+ ovs_be16 forward_delay; /* 8.5.1.8: State progression delay. */
+} __attribute__((packed));
+BUILD_ASSERT_DECL(sizeof(struct stp_config_bpdu) == 35);
+
+struct stp_tcn_bpdu {
+ struct stp_bpdu_header header; /* Type STP_TYPE_TCN. */
+} __attribute__((packed));
+BUILD_ASSERT_DECL(sizeof(struct stp_tcn_bpdu) == 4);
+
+struct stp_timer {
+ bool active; /* Timer in use? */
+ int value; /* Current value of timer, counting up. */
+};
+
+struct stp_port {
+ struct stp *stp;
+ int port_id; /* 8.5.5.1: Unique port identifier. */
+ enum stp_state state; /* 8.5.5.2: Current state. */
+ int path_cost; /* 8.5.5.3: Cost of tx/rx on this port. */
+ stp_identifier designated_root; /* 8.5.5.4. */
+ int designated_cost; /* 8.5.5.5: Path cost to root on port. */
+ stp_identifier designated_bridge; /* 8.5.5.6. */
+ int designated_port; /* 8.5.5.7: Port to send config msgs on. */
+ bool topology_change_ack; /* 8.5.5.8: Flag for next config BPDU. */
+ bool config_pending; /* 8.5.5.9: Send BPDU when hold expires? */
+ bool change_detection_enabled; /* 8.5.5.10: Detect topology changes? */
+
+ struct stp_timer message_age_timer; /* 8.5.6.1: Age of received info. */
+ struct stp_timer forward_delay_timer; /* 8.5.6.2: State change timer. */
+ struct stp_timer hold_timer; /* 8.5.6.3: BPDU rate limit timer. */
+
+ bool state_changed;
+};
+
+struct stp {
+ /* Static bridge data. */
+ char *name; /* Human-readable name for log messages. */
+ stp_identifier bridge_id; /* 8.5.3.7: This bridge. */
+ int max_age; /* 8.5.3.4: Time to drop received data. */
+ int hello_time; /* 8.5.3.5: Time between sending BPDUs. */
+ int forward_delay; /* 8.5.3.6: Delay between state changes. */
+ int bridge_max_age; /* 8.5.3.8: max_age when we're root. */
+ int bridge_hello_time; /* 8.5.3.9: hello_time as root. */
+ int bridge_forward_delay; /* 8.5.3.10: forward_delay as root. */
+ int rq_max_age; /* User-requested max age, in ms. */
+ int rq_hello_time; /* User-requested hello time, in ms. */
+ int rq_forward_delay; /* User-requested forward delay, in ms. */
+ int elapsed_remainder; /* Left-over msecs from last stp_tick(). */
+
+ /* Dynamic bridge data. */
+ stp_identifier designated_root; /* 8.5.3.1: Bridge believed to be root. */
+ unsigned int root_path_cost; /* 8.5.3.2: Cost of path to root. */
+ struct stp_port *root_port; /* 8.5.3.3: Lowest cost port to root. */
+ bool topology_change_detected; /* 8.5.3.11: Detected a topology change? */
+ bool topology_change; /* 8.5.3.12: Received topology change? */
+
+ /* Bridge timers. */
+ struct stp_timer hello_timer; /* 8.5.4.1: Hello timer. */
+ struct stp_timer tcn_timer; /* 8.5.4.2: Topology change timer. */
+ struct stp_timer topology_change_timer; /* 8.5.4.3. */
+
+ /* Ports. */
+ struct stp_port ports[STP_MAX_PORTS];
+
+ /* Interface to client. */
+ struct stp_port *first_changed_port;
+ void (*send_bpdu)(struct ofpbuf *bpdu, int port_no, void *aux);
+ void *aux;
+};
+
+#define FOR_EACH_ENABLED_PORT(PORT, STP) \
+ for ((PORT) = stp_next_enabled_port((STP), (STP)->ports); \
+ (PORT); \
+ (PORT) = stp_next_enabled_port((STP), (PORT) + 1))
+static struct stp_port *
+stp_next_enabled_port(const struct stp *stp, const struct stp_port *port)
+{
+ for (; port < &stp->ports[ARRAY_SIZE(stp->ports)]; port++) {
+ if (port->state != STP_DISABLED) {
+ return (struct stp_port *) port;
+ }
+ }
+ return NULL;
+}
+
+#define MESSAGE_AGE_INCREMENT 1
+
+static void stp_transmit_config(struct stp_port *);
+static bool stp_supersedes_port_info(const struct stp_port *,
+ const struct stp_config_bpdu *);
+static void stp_record_config_information(struct stp_port *,
+ const struct stp_config_bpdu *);
+static void stp_record_config_timeout_values(struct stp *,
+ const struct stp_config_bpdu *);
+static bool stp_is_designated_port(const struct stp_port *);
+static void stp_config_bpdu_generation(struct stp *);
+static void stp_transmit_tcn(struct stp *);
+static void stp_configuration_update(struct stp *);
+static bool stp_supersedes_root(const struct stp_port *root,
+ const struct stp_port *);
+static void stp_root_selection(struct stp *);
+static void stp_designated_port_selection(struct stp *);
+static void stp_become_designated_port(struct stp_port *);
+static void stp_port_state_selection(struct stp *);
+static void stp_make_forwarding(struct stp_port *);
+static void stp_make_blocking(struct stp_port *);
+static void stp_set_port_state(struct stp_port *, enum stp_state);
+static void stp_topology_change_detection(struct stp *);
+static void stp_topology_change_acknowledged(struct stp *);
+static void stp_acknowledge_topology_change(struct stp_port *);
+static void stp_received_config_bpdu(struct stp *, struct stp_port *,
+ const struct stp_config_bpdu *);
+static void stp_received_tcn_bpdu(struct stp *, struct stp_port *);
+static void stp_hello_timer_expiry(struct stp *);
+static void stp_message_age_timer_expiry(struct stp_port *);
+static bool stp_is_designated_for_some_port(const struct stp *);
+static void stp_forward_delay_timer_expiry(struct stp_port *);
+static void stp_tcn_timer_expiry(struct stp *);
+static void stp_topology_change_timer_expiry(struct stp *);
+static void stp_hold_timer_expiry(struct stp_port *);
+static void stp_initialize_port(struct stp_port *, enum stp_state);
+static void stp_become_root_bridge(struct stp *);
+static void stp_update_bridge_timers(struct stp *);
+
+static int clamp(int x, int min, int max);
+static int ms_to_timer(int ms);
+static int ms_to_timer_remainder(int ms);
+static int timer_to_ms(int timer);
+static void stp_start_timer(struct stp_timer *, int value);
+static void stp_stop_timer(struct stp_timer *);
+static bool stp_timer_expired(struct stp_timer *, int elapsed, int timeout);
+
+static void stp_send_bpdu(struct stp_port *, const void *, size_t);
+
+/* Creates and returns a new STP instance that initially has no ports enabled.
+ *
+ * 'bridge_id' should be a 48-bit MAC address as returned by
+ * eth_addr_to_uint64(). 'bridge_id' may also have a priority value in its top
+ * 16 bits; if those bits are set to 0, STP_DEFAULT_BRIDGE_PRIORITY is used.
+ * (This priority may be changed with stp_set_bridge_priority().)
+ *
+ * When the bridge needs to send out a BPDU, it calls 'send_bpdu'. This
+ * callback may be called from stp_tick() or stp_received_bpdu(). The
+ * arguments to 'send_bpdu' are an STP BPDU encapsulated in 'bpdu',
+ * the spanning tree port number 'port_no' that should transmit the
+ * packet, and auxiliary data to be passed to the callback in 'aux'.
+ */
+struct stp *
+stp_create(const char *name, stp_identifier bridge_id,
+ void (*send_bpdu)(struct ofpbuf *bpdu, int port_no, void *aux),
+ void *aux)
+{
+ struct stp *stp;
+ struct stp_port *p;
+
+ stp = xzalloc(sizeof *stp);
+ stp->name = xstrdup(name);
+ stp->bridge_id = bridge_id;
+ if (!(stp->bridge_id >> 48)) {
+ stp->bridge_id |= (uint64_t) STP_DEFAULT_BRIDGE_PRIORITY << 48;
+ }
+
+ stp->rq_max_age = 6000;
+ stp->rq_hello_time = 2000;
+ stp->rq_forward_delay = 4000;
+ stp_update_bridge_timers(stp);
+ stp->max_age = stp->bridge_max_age;
+ stp->hello_time = stp->bridge_hello_time;
+ stp->forward_delay = stp->bridge_forward_delay;
+
+ stp->designated_root = stp->bridge_id;
+ stp->root_path_cost = 0;
+ stp->root_port = NULL;
+ stp->topology_change_detected = false;
+ stp->topology_change = false;
+
+ stp_stop_timer(&stp->tcn_timer);
+ stp_stop_timer(&stp->topology_change_timer);
+ stp_start_timer(&stp->hello_timer, 0);
+
+ stp->send_bpdu = send_bpdu;
+ stp->aux = aux;
+
+ stp->first_changed_port = &stp->ports[ARRAY_SIZE(stp->ports)];
+ for (p = stp->ports; p < &stp->ports[ARRAY_SIZE(stp->ports)]; p++) {
+ p->stp = stp;
+ p->port_id = (stp_port_no(p) + 1) | (STP_DEFAULT_PORT_PRIORITY << 8);
+ p->path_cost = 19; /* Recommended default for 100 Mb/s link. */
+ stp_initialize_port(p, STP_DISABLED);
+ }
+ return stp;
+}
+
+/* Destroys 'stp'. */
+void
+stp_destroy(struct stp *stp)
+{
+ if (stp) {
+ free(stp->name);
+ free(stp);
+ }
+}
+
+/* Runs 'stp' given that 'ms' milliseconds have passed. */
+void
+stp_tick(struct stp *stp, int ms)
+{
+ struct stp_port *p;
+ int elapsed;
+
+ /* Convert 'ms' to STP timer ticks. Preserve any leftover milliseconds
+ * from previous stp_tick() calls so that we don't lose STP ticks when we
+ * are called too frequently. */
+ ms = clamp(ms, 0, INT_MAX - 1000) + stp->elapsed_remainder;
+ elapsed = ms_to_timer(ms);
+ stp->elapsed_remainder = ms_to_timer_remainder(ms);
+ if (!elapsed) {
+ return;
+ }
+
+ if (stp_timer_expired(&stp->hello_timer, elapsed, stp->hello_time)) {
+ stp_hello_timer_expiry(stp);
+ }
+ if (stp_timer_expired(&stp->tcn_timer, elapsed, stp->bridge_hello_time)) {
+ stp_tcn_timer_expiry(stp);
+ }
+ if (stp_timer_expired(&stp->topology_change_timer, elapsed,
+ stp->max_age + stp->forward_delay)) {
+ stp_topology_change_timer_expiry(stp);
+ }
+ FOR_EACH_ENABLED_PORT (p, stp) {
+ if (stp_timer_expired(&p->message_age_timer, elapsed, stp->max_age)) {
+ stp_message_age_timer_expiry(p);
+ }
+ }
+ FOR_EACH_ENABLED_PORT (p, stp) {
+ if (stp_timer_expired(&p->forward_delay_timer, elapsed,
+ stp->forward_delay)) {
+ stp_forward_delay_timer_expiry(p);
+ }
+ if (stp_timer_expired(&p->hold_timer, elapsed, ms_to_timer(1000))) {
+ stp_hold_timer_expiry(p);
+ }
+ }
+}
+
+static void
+set_bridge_id(struct stp *stp, stp_identifier new_bridge_id)
+{
+ if (new_bridge_id != stp->bridge_id) {
+ bool root;
+ struct stp_port *p;
+
+ root = stp_is_root_bridge(stp);
+ FOR_EACH_ENABLED_PORT (p, stp) {
+ if (stp_is_designated_port(p)) {
+ p->designated_bridge = new_bridge_id;
+ }
+ }
+ stp->bridge_id = new_bridge_id;
+ stp_configuration_update(stp);
+ stp_port_state_selection(stp);
+ if (stp_is_root_bridge(stp) && !root) {
+ stp_become_root_bridge(stp);
+ }
+ }
+}
+
+void
+stp_set_bridge_id(struct stp *stp, stp_identifier bridge_id)
+{
+ const uint64_t mac_bits = (UINT64_C(1) << 48) - 1;
+ const uint64_t pri_bits = ~mac_bits;
+ set_bridge_id(stp, (stp->bridge_id & pri_bits) | (bridge_id & mac_bits));
+}
+
+void
+stp_set_bridge_priority(struct stp *stp, uint16_t new_priority)
+{
+ const uint64_t mac_bits = (UINT64_C(1) << 48) - 1;
+ set_bridge_id(stp, ((stp->bridge_id & mac_bits)
+ | ((uint64_t) new_priority << 48)));
+}
+
+/* Sets the desired hello time for 'stp' to 'ms', in milliseconds. The actual
+ * hello time is clamped to the range of 1 to 10 seconds and subject to the
+ * relationship (bridge_max_age >= 2 * (bridge_hello_time + 1 s)). The bridge
+ * hello time is only used when 'stp' is the root bridge. */
+void
+stp_set_hello_time(struct stp *stp, int ms)
+{
+ stp->rq_hello_time = ms;
+ stp_update_bridge_timers(stp);
+}
+
+/* Sets the desired max age for 'stp' to 'ms', in milliseconds. The actual max
+ * age is clamped to the range of 6 to 40 seconds and subject to the
+ * relationships (2 * (bridge_forward_delay - 1 s) >= bridge_max_age) and
+ * (bridge_max_age >= 2 * (bridge_hello_time + 1 s)). The bridge max age is
+ * only used when 'stp' is the root bridge. */
+void
+stp_set_max_age(struct stp *stp, int ms)
+{
+ stp->rq_max_age = ms;
+ stp_update_bridge_timers(stp);
+}
+
+/* Sets the desired forward delay for 'stp' to 'ms', in milliseconds. The
+ * actual forward delay is clamped to the range of 4 to 30 seconds and subject
+ * to the relationship (2 * (bridge_forward_delay - 1 s) >= bridge_max_age).
+ * The bridge forward delay is only used when 'stp' is the root bridge. */
+void
+stp_set_forward_delay(struct stp *stp, int ms)
+{
+ stp->rq_forward_delay = ms;
+ stp_update_bridge_timers(stp);
+}
+
+/* Returns the name given to 'stp' in the call to stp_create(). */
+const char *
+stp_get_name(const struct stp *stp)
+{
+ return stp->name;
+}
+
+/* Returns the bridge ID for 'stp'. */
+stp_identifier
+stp_get_bridge_id(const struct stp *stp)
+{
+ return stp->bridge_id;
+}
+
+/* Returns the bridge ID of the bridge currently believed to be the root. */
+stp_identifier
+stp_get_designated_root(const struct stp *stp)
+{
+ return stp->designated_root;
+}
+
+/* Returns true if 'stp' believes itself to the be root of the spanning tree,
+ * false otherwise. */
+bool
+stp_is_root_bridge(const struct stp *stp)
+{
+ return stp->bridge_id == stp->designated_root;
+}
+
+/* Returns the cost of the path from 'stp' to the root of the spanning tree. */
+int
+stp_get_root_path_cost(const struct stp *stp)
+{
+ return stp->root_path_cost;
+}
+
+/* Returns the bridge hello time, in ms. The returned value is not necessarily
+ * the value passed to stp_set_hello_time(): it is clamped to the valid range
+ * and quantized to the STP timer resolution. */
+int
+stp_get_hello_time(const struct stp *stp)
+{
+ return timer_to_ms(stp->bridge_hello_time);
+}
+
+/* Returns the bridge max age, in ms. The returned value is not necessarily
+ * the value passed to stp_set_max_age(): it is clamped to the valid range,
+ * quantized to the STP timer resolution, and adjusted to match the constraints
+ * due to the hello time. */
+int
+stp_get_max_age(const struct stp *stp)
+{
+ return timer_to_ms(stp->bridge_max_age);
+}
+
+/* Returns the bridge forward delay, in ms. The returned value is not
+ * necessarily the value passed to stp_set_forward_delay(): it is clamped to
+ * the valid range, quantized to the STP timer resolution, and adjusted to
+ * match the constraints due to the forward delay. */
+int
+stp_get_forward_delay(const struct stp *stp)
+{
+ return timer_to_ms(stp->bridge_forward_delay);
+}
+
+/* Returns the port in 'stp' with index 'port_no', which must be between 0 and
+ * STP_MAX_PORTS. */
+struct stp_port *
+stp_get_port(struct stp *stp, int port_no)
+{
+ assert(port_no >= 0 && port_no < ARRAY_SIZE(stp->ports));
+ return &stp->ports[port_no];
+}
+
+/* Returns the port connecting 'stp' to the root bridge, or a null pointer if
+ * there is no such port. */
+struct stp_port *
+stp_get_root_port(struct stp *stp)
+{
+ return stp->root_port;
+}
+
+/* Finds a port whose state has changed. If successful, stores the port whose
+ * state changed in '*portp' and returns true. If no port has changed, stores
+ * NULL in '*portp' and returns false. */
+bool
+stp_get_changed_port(struct stp *stp, struct stp_port **portp)
+{
+ struct stp_port *end = &stp->ports[ARRAY_SIZE(stp->ports)];
+ struct stp_port *p;
+
+ for (p = stp->first_changed_port; p < end; p++) {
+ if (p->state_changed) {
+ p->state_changed = false;
+ stp->first_changed_port = p + 1;
+ *portp = p;
+ return true;
+ }
+ }
+ stp->first_changed_port = end;
+ *portp = NULL;
+ return false;
+}
+
+/* Returns the name for the given 'state' (for use in debugging and log
+ * messages). */
+const char *
+stp_state_name(enum stp_state state)
+{
+ switch (state) {
+ case STP_DISABLED:
+ return "disabled";
+ case STP_LISTENING:
+ return "listening";
+ case STP_LEARNING:
+ return "learning";
+ case STP_FORWARDING:
+ return "forwarding";
+ case STP_BLOCKING:
+ return "blocking";
+ default:
+ NOT_REACHED();
+ }
+}
+
+/* Returns true if 'state' is one in which packets received on a port should
+ * be forwarded, false otherwise.
+ *
+ * Returns true if 'state' is STP_DISABLED, since presumably in that case the
+ * port should still work, just not have STP applied to it. */
+bool
+stp_forward_in_state(enum stp_state state)
+{
+ return (state & (STP_DISABLED | STP_FORWARDING)) != 0;
+}
+
+/* Returns true if 'state' is one in which MAC learning should be done on
+ * packets received on a port, false otherwise.
+ *
+ * Returns true if 'state' is STP_DISABLED, since presumably in that case the
+ * port should still work, just not have STP applied to it. */
+bool
+stp_learn_in_state(enum stp_state state)
+{
+ return (state & (STP_DISABLED | STP_LEARNING | STP_FORWARDING)) != 0;
+}
+
+/* Notifies the STP entity that bridge protocol data unit 'bpdu', which is
+ * 'bpdu_size' bytes in length, was received on port 'p'.
+ *
+ * This function may call the 'send_bpdu' function provided to stp_create(). */
+void
+stp_received_bpdu(struct stp_port *p, const void *bpdu, size_t bpdu_size)
+{
+ struct stp *stp = p->stp;
+ const struct stp_bpdu_header *header;
+
+ if (p->state == STP_DISABLED) {
+ return;
+ }
+
+ if (bpdu_size < sizeof(struct stp_bpdu_header)) {
+ VLOG_WARN("%s: received runt %zu-byte BPDU", stp->name, bpdu_size);
+ return;
+ }
+
+ header = bpdu;
+ if (header->protocol_id != htons(STP_PROTOCOL_ID)) {
+ VLOG_WARN("%s: received BPDU with unexpected protocol ID %"PRIu16,
+ stp->name, ntohs(header->protocol_id));
+ return;
+ }
+ if (header->protocol_version != STP_PROTOCOL_VERSION) {
+ VLOG_DBG("%s: received BPDU with unexpected protocol version %"PRIu8,
+ stp->name, header->protocol_version);
+ }
+
+ switch (header->bpdu_type) {
+ case STP_TYPE_CONFIG:
+ if (bpdu_size < sizeof(struct stp_config_bpdu)) {
+ VLOG_WARN("%s: received config BPDU with invalid size %zu",
+ stp->name, bpdu_size);
+ return;
+ }
+ stp_received_config_bpdu(stp, p, bpdu);
+ break;
+
+ case STP_TYPE_TCN:
+ if (bpdu_size != sizeof(struct stp_tcn_bpdu)) {
+ VLOG_WARN("%s: received TCN BPDU with invalid size %zu",
+ stp->name, bpdu_size);
+ return;
+ }
+ stp_received_tcn_bpdu(stp, p);
+ break;
+
+ default:
+ VLOG_WARN("%s: received BPDU of unexpected type %"PRIu8,
+ stp->name, header->bpdu_type);
+ return;
+ }
+}
+
+/* Returns the STP entity in which 'p' is nested. */
+struct stp *
+stp_port_get_stp(struct stp_port *p)
+{
+ return p->stp;
+}
+
+/* Returns the index of port 'p' within its bridge. */
+int
+stp_port_no(const struct stp_port *p)
+{
+ struct stp *stp = p->stp;
+ assert(p >= stp->ports && p < &stp->ports[ARRAY_SIZE(stp->ports)]);
+ return p - stp->ports;
+}
+
+/* Returns the state of port 'p'. */
+enum stp_state
+stp_port_get_state(const struct stp_port *p)
+{
+ return p->state;
+}
+
+/* Disables STP on port 'p'. */
+void
+stp_port_disable(struct stp_port *p)
+{
+ struct stp *stp = p->stp;
+ if (p->state != STP_DISABLED) {
+ bool root = stp_is_root_bridge(stp);
+ stp_become_designated_port(p);
+ stp_set_port_state(p, STP_DISABLED);
+ p->topology_change_ack = false;
+ p->config_pending = false;
+ stp_stop_timer(&p->message_age_timer);
+ stp_stop_timer(&p->forward_delay_timer);
+ stp_configuration_update(stp);
+ stp_port_state_selection(stp);
+ if (stp_is_root_bridge(stp) && !root) {
+ stp_become_root_bridge(stp);
+ }
+ }
+}
+
+/* Enables STP on port 'p'. The port will initially be in "blocking" state. */
+void
+stp_port_enable(struct stp_port *p)
+{
+ if (p->state == STP_DISABLED) {
+ stp_initialize_port(p, STP_BLOCKING);
+ stp_port_state_selection(p->stp);
+ }
+}
+
+/* Sets the priority of port 'p' to 'new_priority'. Lower numerical values
+ * are interpreted as higher priorities. */
+void
+stp_port_set_priority(struct stp_port *p, uint8_t new_priority)
+{
+ uint16_t new_port_id = (p->port_id & 0xff) | (new_priority << 8);
+ if (p->port_id != new_port_id) {
+ struct stp *stp = p->stp;
+ if (stp_is_designated_port(p)) {
+ p->designated_port = new_port_id;
+ }
+ p->port_id = new_port_id;
+ if (stp->bridge_id == p->designated_bridge
+ && p->port_id < p->designated_port) {
+ stp_become_designated_port(p);
+ stp_port_state_selection(stp);
+ }
+ }
+}
+
+/* Sets the path cost of port 'p' to 'path_cost'. Lower values are generally
+ * used to indicate faster links. Use stp_port_set_speed() to automatically
+ * generate a default path cost from a link speed. */
+void
+stp_port_set_path_cost(struct stp_port *p, uint16_t path_cost)
+{
+ if (p->path_cost != path_cost) {
+ struct stp *stp = p->stp;
+ p->path_cost = path_cost;
+ stp_configuration_update(stp);
+ stp_port_state_selection(stp);
+ }
+}
+
+/* Sets the path cost of port 'p' based on 'speed' (measured in Mb/s). */
+void
+stp_port_set_speed(struct stp_port *p, unsigned int speed)
+{
+ stp_port_set_path_cost(p, (speed >= 10000 ? 2 /* 10 Gb/s. */
+ : speed >= 1000 ? 4 /* 1 Gb/s. */
+ : speed >= 100 ? 19 /* 100 Mb/s. */
+ : speed >= 16 ? 62 /* 16 Mb/s. */
+ : speed >= 10 ? 100 /* 10 Mb/s. */
+ : speed >= 4 ? 250 /* 4 Mb/s. */
+ : 19)); /* 100 Mb/s (guess). */
+}
+
+/* Enables topology change detection on port 'p'. */
+void
+stp_port_enable_change_detection(struct stp_port *p)
+{
+ p->change_detection_enabled = true;
+}
+
+/* Disables topology change detection on port 'p'. */
+void
+stp_port_disable_change_detection(struct stp_port *p)
+{
+ p->change_detection_enabled = false;
+}
+\f
+static void
+stp_transmit_config(struct stp_port *p)
+{
+ struct stp *stp = p->stp;
+ bool root = stp_is_root_bridge(stp);
+ if (!root && !stp->root_port) {
+ return;
+ }
+ if (p->hold_timer.active) {
+ p->config_pending = true;
+ } else {
+ struct stp_config_bpdu config;
+ memset(&config, 0, sizeof config);
+ config.header.protocol_id = htons(STP_PROTOCOL_ID);
+ config.header.protocol_version = STP_PROTOCOL_VERSION;
+ config.header.bpdu_type = STP_TYPE_CONFIG;
+ config.flags = 0;
+ if (p->topology_change_ack) {
+ config.flags |= htons(STP_CONFIG_TOPOLOGY_CHANGE_ACK);
+ }
+ if (stp->topology_change) {
+ config.flags |= htons(STP_CONFIG_TOPOLOGY_CHANGE);
+ }
+ config.root_id = htonll(stp->designated_root);
+ config.root_path_cost = htonl(stp->root_path_cost);
+ config.bridge_id = htonll(stp->bridge_id);
+ config.port_id = htons(p->port_id);
+ if (root) {
+ config.message_age = htons(0);
+ } else {
+ config.message_age = htons(stp->root_port->message_age_timer.value
+ + MESSAGE_AGE_INCREMENT);
+ }
+ config.max_age = htons(stp->max_age);
+ config.hello_time = htons(stp->hello_time);
+ config.forward_delay = htons(stp->forward_delay);
+ if (ntohs(config.message_age) < stp->max_age) {
+ p->topology_change_ack = false;
+ p->config_pending = false;
+ stp_send_bpdu(p, &config, sizeof config);
+ stp_start_timer(&p->hold_timer, 0);
+ }
+ }
+}
+
+static bool
+stp_supersedes_port_info(const struct stp_port *p,
+ const struct stp_config_bpdu *config)
+{
+ if (ntohll(config->root_id) != p->designated_root) {
+ return ntohll(config->root_id) < p->designated_root;
+ } else if (ntohl(config->root_path_cost) != p->designated_cost) {
+ return ntohl(config->root_path_cost) < p->designated_cost;
+ } else if (ntohll(config->bridge_id) != p->designated_bridge) {
+ return ntohll(config->bridge_id) < p->designated_bridge;
+ } else {
+ return (ntohll(config->bridge_id) != p->stp->bridge_id
+ || ntohs(config->port_id) <= p->designated_port);
+ }
+}
+
+static void
+stp_record_config_information(struct stp_port *p,
+ const struct stp_config_bpdu *config)
+{
+ p->designated_root = ntohll(config->root_id);
+ p->designated_cost = ntohl(config->root_path_cost);
+ p->designated_bridge = ntohll(config->bridge_id);
+ p->designated_port = ntohs(config->port_id);
+ stp_start_timer(&p->message_age_timer, ntohs(config->message_age));
+}
+
+static void
+stp_record_config_timeout_values(struct stp *stp,
+ const struct stp_config_bpdu *config)
+{
+ stp->max_age = ntohs(config->max_age);
+ stp->hello_time = ntohs(config->hello_time);
+ stp->forward_delay = ntohs(config->forward_delay);
+ stp->topology_change = config->flags & htons(STP_CONFIG_TOPOLOGY_CHANGE);
+}
+
+static bool
+stp_is_designated_port(const struct stp_port *p)
+{
+ return (p->designated_bridge == p->stp->bridge_id
+ && p->designated_port == p->port_id);
+}
+
+static void
+stp_config_bpdu_generation(struct stp *stp)
+{
+ struct stp_port *p;
+
+ FOR_EACH_ENABLED_PORT (p, stp) {
+ if (stp_is_designated_port(p)) {
+ stp_transmit_config(p);
+ }
+ }
+}
+
+static void
+stp_transmit_tcn(struct stp *stp)
+{
+ struct stp_port *p = stp->root_port;
+ struct stp_tcn_bpdu tcn_bpdu;
+ if (!p) {
+ return;
+ }
+ tcn_bpdu.header.protocol_id = htons(STP_PROTOCOL_ID);
+ tcn_bpdu.header.protocol_version = STP_PROTOCOL_VERSION;
+ tcn_bpdu.header.bpdu_type = STP_TYPE_TCN;
+ stp_send_bpdu(p, &tcn_bpdu, sizeof tcn_bpdu);
+}
+
+static void
+stp_configuration_update(struct stp *stp)
+{
+ stp_root_selection(stp);
+ stp_designated_port_selection(stp);
+}
+
+static bool
+stp_supersedes_root(const struct stp_port *root, const struct stp_port *p)
+{
+ int p_cost = p->designated_cost + p->path_cost;
+ int root_cost = root->designated_cost + root->path_cost;
+
+ if (p->designated_root != root->designated_root) {
+ return p->designated_root < root->designated_root;
+ } else if (p_cost != root_cost) {
+ return p_cost < root_cost;
+ } else if (p->designated_bridge != root->designated_bridge) {
+ return p->designated_bridge < root->designated_bridge;
+ } else if (p->designated_port != root->designated_port) {
+ return p->designated_port < root->designated_port;
+ } else {
+ return p->port_id < root->port_id;
+ }
+}
+
+static void
+stp_root_selection(struct stp *stp)
+{
+ struct stp_port *p, *root;
+
+ root = NULL;
+ FOR_EACH_ENABLED_PORT (p, stp) {
+ if (stp_is_designated_port(p)
+ || p->designated_root >= stp->bridge_id) {
+ continue;
+ }
+ if (root && !stp_supersedes_root(root, p)) {
+ continue;
+ }
+ root = p;
+ }
+ stp->root_port = root;
+ if (!root) {
+ stp->designated_root = stp->bridge_id;
+ stp->root_path_cost = 0;
+ } else {
+ stp->designated_root = root->designated_root;
+ stp->root_path_cost = root->designated_cost + root->path_cost;
+ }
+}
+
+static void
+stp_designated_port_selection(struct stp *stp)
+{
+ struct stp_port *p;
+
+ FOR_EACH_ENABLED_PORT (p, stp) {
+ if (stp_is_designated_port(p)
+ || p->designated_root != stp->designated_root
+ || stp->root_path_cost < p->designated_cost
+ || (stp->root_path_cost == p->designated_cost
+ && (stp->bridge_id < p->designated_bridge
+ || (stp->bridge_id == p->designated_bridge
+ && p->port_id <= p->designated_port))))
+ {
+ stp_become_designated_port(p);
+ }
+ }
+}
+
+static void
+stp_become_designated_port(struct stp_port *p)
+{
+ struct stp *stp = p->stp;
+ p->designated_root = stp->designated_root;
+ p->designated_cost = stp->root_path_cost;
+ p->designated_bridge = stp->bridge_id;
+ p->designated_port = p->port_id;
+}
+
+static void
+stp_port_state_selection(struct stp *stp)
+{
+ struct stp_port *p;
+
+ FOR_EACH_ENABLED_PORT (p, stp) {
+ if (p == stp->root_port) {
+ p->config_pending = false;
+ p->topology_change_ack = false;
+ stp_make_forwarding(p);
+ } else if (stp_is_designated_port(p)) {
+ stp_stop_timer(&p->message_age_timer);
+ stp_make_forwarding(p);
+ } else {
+ p->config_pending = false;
+ p->topology_change_ack = false;
+ stp_make_blocking(p);
+ }
+ }
+}
+
+static void
+stp_make_forwarding(struct stp_port *p)
+{
+ if (p->state == STP_BLOCKING) {
+ stp_set_port_state(p, STP_LISTENING);
+ stp_start_timer(&p->forward_delay_timer, 0);
+ }
+}
+
+static void
+stp_make_blocking(struct stp_port *p)
+{
+ if (!(p->state & (STP_DISABLED | STP_BLOCKING))) {
+ if (p->state & (STP_FORWARDING | STP_LEARNING)) {
+ if (p->change_detection_enabled) {
+ stp_topology_change_detection(p->stp);
+ }
+ }
+ stp_set_port_state(p, STP_BLOCKING);
+ stp_stop_timer(&p->forward_delay_timer);
+ }
+}
+
+static void
+stp_set_port_state(struct stp_port *p, enum stp_state state)
+{
+ if (state != p->state && !p->state_changed) {
+ p->state_changed = true;
+ if (p < p->stp->first_changed_port) {
+ p->stp->first_changed_port = p;
+ }
+ }
+ p->state = state;
+}
+
+static void
+stp_topology_change_detection(struct stp *stp)
+{
+ if (stp_is_root_bridge(stp)) {
+ stp->topology_change = true;
+ stp_start_timer(&stp->topology_change_timer, 0);
+ } else if (!stp->topology_change_detected) {
+ stp_transmit_tcn(stp);
+ stp_start_timer(&stp->tcn_timer, 0);
+ }
+ stp->topology_change_detected = true;
+}
+
+static void
+stp_topology_change_acknowledged(struct stp *stp)
+{
+ stp->topology_change_detected = false;
+ stp_stop_timer(&stp->tcn_timer);
+}
+
+static void
+stp_acknowledge_topology_change(struct stp_port *p)
+{
+ p->topology_change_ack = true;
+ stp_transmit_config(p);
+}
+
+static void
+stp_received_config_bpdu(struct stp *stp, struct stp_port *p,
+ const struct stp_config_bpdu *config)
+{
+ if (ntohs(config->message_age) >= ntohs(config->max_age)) {
+ VLOG_WARN("%s: received config BPDU with message age (%u) greater "
+ "than max age (%u)",
+ stp->name,
+ ntohs(config->message_age), ntohs(config->max_age));
+ return;
+ }
+ if (p->state != STP_DISABLED) {
+ bool root = stp_is_root_bridge(stp);
+ if (stp_supersedes_port_info(p, config)) {
+ stp_record_config_information(p, config);
+ stp_configuration_update(stp);
+ stp_port_state_selection(stp);
+ if (!stp_is_root_bridge(stp) && root) {
+ stp_stop_timer(&stp->hello_timer);
+ if (stp->topology_change_detected) {
+ stp_stop_timer(&stp->topology_change_timer);
+ stp_transmit_tcn(stp);
+ stp_start_timer(&stp->tcn_timer, 0);
+ }
+ }
+ if (p == stp->root_port) {
+ stp_record_config_timeout_values(stp, config);
+ stp_config_bpdu_generation(stp);
+ if (config->flags & htons(STP_CONFIG_TOPOLOGY_CHANGE_ACK)) {
+ stp_topology_change_acknowledged(stp);
+ }
+ }
+ } else if (stp_is_designated_port(p)) {
+ stp_transmit_config(p);
+ }
+ }
+}
+
+static void
+stp_received_tcn_bpdu(struct stp *stp, struct stp_port *p)
+{
+ if (p->state != STP_DISABLED) {
+ if (stp_is_designated_port(p)) {
+ stp_topology_change_detection(stp);
+ stp_acknowledge_topology_change(p);
+ }
+ }
+}
+
+static void
+stp_hello_timer_expiry(struct stp *stp)
+{
+ stp_config_bpdu_generation(stp);
+ stp_start_timer(&stp->hello_timer, 0);
+}
+
+static void
+stp_message_age_timer_expiry(struct stp_port *p)
+{
+ struct stp *stp = p->stp;
+ bool root = stp_is_root_bridge(stp);
+ stp_become_designated_port(p);
+ stp_configuration_update(stp);
+ stp_port_state_selection(stp);
+ if (stp_is_root_bridge(stp) && !root) {
+ stp->max_age = stp->bridge_max_age;
+ stp->hello_time = stp->bridge_hello_time;
+ stp->forward_delay = stp->bridge_forward_delay;
+ stp_topology_change_detection(stp);
+ stp_stop_timer(&stp->tcn_timer);
+ stp_config_bpdu_generation(stp);
+ stp_start_timer(&stp->hello_timer, 0);
+ }
+}
+
+static bool
+stp_is_designated_for_some_port(const struct stp *stp)
+{
+ const struct stp_port *p;
+
+ FOR_EACH_ENABLED_PORT (p, stp) {
+ if (p->designated_bridge == stp->bridge_id) {
+ return true;
+ }
+ }
+ return false;
+}
+
+static void
+stp_forward_delay_timer_expiry(struct stp_port *p)
+{
+ if (p->state == STP_LISTENING) {
+ stp_set_port_state(p, STP_LEARNING);
+ stp_start_timer(&p->forward_delay_timer, 0);
+ } else if (p->state == STP_LEARNING) {
+ stp_set_port_state(p, STP_FORWARDING);
+ if (stp_is_designated_for_some_port(p->stp)) {
+ if (p->change_detection_enabled) {
+ stp_topology_change_detection(p->stp);
+ }
+ }
+ }
+}
+
+static void
+stp_tcn_timer_expiry(struct stp *stp)
+{
+ stp_transmit_tcn(stp);
+ stp_start_timer(&stp->tcn_timer, 0);
+}
+
+static void
+stp_topology_change_timer_expiry(struct stp *stp)
+{
+ stp->topology_change_detected = false;
+ stp->topology_change = false;
+}
+
+static void
+stp_hold_timer_expiry(struct stp_port *p)
+{
+ if (p->config_pending) {
+ stp_transmit_config(p);
+ }
+}
+
+static void
+stp_initialize_port(struct stp_port *p, enum stp_state state)
+{
+ assert(state & (STP_DISABLED | STP_BLOCKING));
+ stp_become_designated_port(p);
+ stp_set_port_state(p, state);
+ p->topology_change_ack = false;
+ p->config_pending = false;
+ p->change_detection_enabled = true;
+ stp_stop_timer(&p->message_age_timer);
+ stp_stop_timer(&p->forward_delay_timer);
+ stp_stop_timer(&p->hold_timer);
+}
+
+static void
+stp_become_root_bridge(struct stp *stp)
+{
+ stp->max_age = stp->bridge_max_age;
+ stp->hello_time = stp->bridge_hello_time;
+ stp->forward_delay = stp->bridge_forward_delay;
+ stp_topology_change_detection(stp);
+ stp_stop_timer(&stp->tcn_timer);
+ stp_config_bpdu_generation(stp);
+ stp_start_timer(&stp->hello_timer, 0);
+}
+
+static void
+stp_start_timer(struct stp_timer *timer, int value)
+{
+ timer->value = value;
+ timer->active = true;
+}
+
+static void
+stp_stop_timer(struct stp_timer *timer)
+{
+ timer->active = false;
+}
+
+static bool
+stp_timer_expired(struct stp_timer *timer, int elapsed, int timeout)
+{
+ if (timer->active) {
+ timer->value += elapsed;
+ if (timer->value >= timeout) {
+ timer->active = false;
+ return true;
+ }
+ }
+ return false;
+}
+
+/* Returns the number of whole STP timer ticks in 'ms' milliseconds. There
+ * are 256 STP timer ticks per second. */
+static int
+ms_to_timer(int ms)
+{
+ return ms * 0x100 / 1000;
+}
+
+/* Returns the number of leftover milliseconds when 'ms' is converted to STP
+ * timer ticks. */
+static int
+ms_to_timer_remainder(int ms)
+{
+ return ms * 0x100 % 1000;
+}
+
+/* Returns the number of whole milliseconds in 'timer' STP timer ticks. There
+ * are 256 STP timer ticks per second. */
+static int
+timer_to_ms(int timer)
+{
+ return timer * 1000 / 0x100;
+}
+
+static int
+clamp(int x, int min, int max)
+{
+ return x < min ? min : x > max ? max : x;
+}
+
+static void
+stp_update_bridge_timers(struct stp *stp)
+{
+ int ht, ma, fd;
+
+ ht = clamp(stp->rq_hello_time, 1000, 10000);
+ ma = clamp(stp->rq_max_age, MAX(2 * (ht + 1000), 6000), 40000);
+ fd = clamp(stp->rq_forward_delay, ma / 2 + 1000, 30000);
+
+ stp->bridge_hello_time = ms_to_timer(ht);
+ stp->bridge_max_age = ms_to_timer(ma);
+ stp->bridge_forward_delay = ms_to_timer(fd);
+
+ if (stp_is_root_bridge(stp)) {
+ stp->max_age = stp->bridge_max_age;
+ stp->hello_time = stp->bridge_hello_time;
+ stp->forward_delay = stp->bridge_forward_delay;
+ }
+}
+
+static void
+stp_send_bpdu(struct stp_port *p, const void *bpdu, size_t bpdu_size)
+{
+ struct eth_header *eth;
+ struct llc_header *llc;
+ struct ofpbuf *pkt;
+
+ /* Skeleton. */
+ pkt = ofpbuf_new(ETH_HEADER_LEN + LLC_HEADER_LEN + bpdu_size);
+ pkt->l2 = eth = ofpbuf_put_zeros(pkt, sizeof *eth);
+ llc = ofpbuf_put_zeros(pkt, sizeof *llc);
+ pkt->l3 = ofpbuf_put(pkt, bpdu, bpdu_size);
+
+ /* 802.2 header. */
+ memcpy(eth->eth_dst, eth_addr_stp, ETH_ADDR_LEN);
+ /* p->stp->send_bpdu() must fill in source address. */
+ eth->eth_type = htons(pkt->size - ETH_HEADER_LEN);
+
+ /* LLC header. */
+ llc->llc_dsap = STP_LLC_DSAP;
+ llc->llc_ssap = STP_LLC_SSAP;
+ llc->llc_cntl = STP_LLC_CNTL;
+
+ p->stp->send_bpdu(pkt, stp_port_no(p), p->stp->aux);
+}
--- /dev/null
+/*
+ * Copyright (c) 2008, 2009, 2010 Nicira Networks.
+ *
+ * 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 <config.h>
+
+#include "stp.h"
+#include <assert.h>
+#include <ctype.h>
+#include <errno.h>
+#include <inttypes.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include "ofpbuf.h"
+#include "packets.h"
+
+struct bpdu {
+ int port_no;
+ void *data;
+ size_t size;
+};
+
+struct bridge {
+ struct test_case *tc;
+ int id;
+ bool reached;
+
+ struct stp *stp;
+
+ struct lan *ports[STP_MAX_PORTS];
+ int n_ports;
+
+#define RXQ_SIZE 16
+ struct bpdu rxq[RXQ_SIZE];
+ int rxq_head, rxq_tail;
+};
+
+struct lan_conn {
+ struct bridge *bridge;
+ int port_no;
+};
+
+struct lan {
+ struct test_case *tc;
+ const char *name;
+ bool reached;
+ struct lan_conn conns[16];
+ int n_conns;
+};
+
+struct test_case {
+ struct bridge *bridges[16];
+ int n_bridges;
+ struct lan *lans[26];
+ int n_lans;
+};
+
+static const char *file_name;
+static int line_number;
+static char line[128];
+static char *pos, *token;
+static int n_warnings;
+
+static struct test_case *
+new_test_case(void)
+{
+ struct test_case *tc = xmalloc(sizeof *tc);
+ tc->n_bridges = 0;
+ tc->n_lans = 0;
+ return tc;
+}
+
+static void
+send_bpdu(struct ofpbuf *pkt, int port_no, void *b_)
+{
+ struct bridge *b = b_;
+ struct lan *lan;
+
+ assert(port_no < b->n_ports);
+ lan = b->ports[port_no];
+ if (lan) {
+ const void *data = pkt->l3;
+ size_t size = (char *) ofpbuf_tail(pkt) - (char *) data;
+ int i;
+
+ for (i = 0; i < lan->n_conns; i++) {
+ struct lan_conn *conn = &lan->conns[i];
+ if (conn->bridge != b || conn->port_no != port_no) {
+ struct bridge *dst = conn->bridge;
+ struct bpdu *bpdu = &dst->rxq[dst->rxq_head++ % RXQ_SIZE];
+ assert(dst->rxq_head - dst->rxq_tail <= RXQ_SIZE);
+ bpdu->data = xmemdup(data, size);
+ bpdu->size = size;
+ bpdu->port_no = conn->port_no;
+ }
+ }
+ }
+ ofpbuf_delete(pkt);
+}
+
+static struct bridge *
+new_bridge(struct test_case *tc, int id)
+{
+ struct bridge *b = xmalloc(sizeof *b);
+ char name[16];
+ b->tc = tc;
+ b->id = id;
+ snprintf(name, sizeof name, "stp%x", id);
+ b->stp = stp_create(name, id, send_bpdu, b);
+ assert(tc->n_bridges < ARRAY_SIZE(tc->bridges));
+ b->n_ports = 0;
+ b->rxq_head = b->rxq_tail = 0;
+ tc->bridges[tc->n_bridges++] = b;
+ return b;
+}
+
+static struct lan *
+new_lan(struct test_case *tc, const char *name)
+{
+ struct lan *lan = xmalloc(sizeof *lan);
+ lan->tc = tc;
+ lan->name = xstrdup(name);
+ lan->n_conns = 0;
+ assert(tc->n_lans < ARRAY_SIZE(tc->lans));
+ tc->lans[tc->n_lans++] = lan;
+ return lan;
+}
+
+static void
+reconnect_port(struct bridge *b, int port_no, struct lan *new_lan)
+{
+ struct lan *old_lan;
+ int j;
+
+ assert(port_no < b->n_ports);
+ old_lan = b->ports[port_no];
+ if (old_lan == new_lan) {
+ return;
+ }
+
+ /* Disconnect from old_lan. */
+ if (old_lan) {
+ for (j = 0; j < old_lan->n_conns; j++) {
+ struct lan_conn *c = &old_lan->conns[j];
+ if (c->bridge == b && c->port_no == port_no) {
+ memmove(c, c + 1, sizeof *c * (old_lan->n_conns - j - 1));
+ old_lan->n_conns--;
+ break;
+ }
+ }
+ }
+
+ /* Connect to new_lan. */
+ b->ports[port_no] = new_lan;
+ if (new_lan) {
+ int conn_no = new_lan->n_conns++;
+ assert(conn_no < ARRAY_SIZE(new_lan->conns));
+ new_lan->conns[conn_no].bridge = b;
+ new_lan->conns[conn_no].port_no = port_no;
+ }
+}
+
+static void
+new_port(struct bridge *b, struct lan *lan, int path_cost)
+{
+ int port_no = b->n_ports++;
+ struct stp_port *p = stp_get_port(b->stp, port_no);
+ assert(port_no < ARRAY_SIZE(b->ports));
+ b->ports[port_no] = NULL;
+ stp_port_set_path_cost(p, path_cost);
+ stp_port_enable(p);
+ reconnect_port(b, port_no, lan);
+}
+
+static void
+dump(struct test_case *tc)
+{
+ int i;
+
+ for (i = 0; i < tc->n_bridges; i++) {
+ struct bridge *b = tc->bridges[i];
+ struct stp *stp = b->stp;
+ int j;
+
+ printf("%s:", stp_get_name(stp));
+ if (stp_is_root_bridge(stp)) {
+ printf(" root");
+ }
+ printf("\n");
+ for (j = 0; j < b->n_ports; j++) {
+ struct stp_port *p = stp_get_port(stp, j);
+ enum stp_state state = stp_port_get_state(p);
+
+ printf("\tport %d", j);
+ if (b->ports[j]) {
+ printf(" (lan %s)", b->ports[j]->name);
+ } else {
+ printf(" (disconnected)");
+ }
+ printf(": %s", stp_state_name(state));
+ if (p == stp_get_root_port(stp)) {
+ printf(" (root port, root_path_cost=%u)", stp_get_root_path_cost(stp));
+ }
+ printf("\n");
+ }
+ }
+}
+
+static void dump_lan_tree(struct test_case *, struct lan *, int level);
+
+static void
+dump_bridge_tree(struct test_case *tc, struct bridge *b, int level)
+{
+ int i;
+
+ if (b->reached) {
+ return;
+ }
+ b->reached = true;
+ for (i = 0; i < level; i++) {
+ printf("\t");
+ }
+ printf("%s\n", stp_get_name(b->stp));
+ for (i = 0; i < b->n_ports; i++) {
+ struct lan *lan = b->ports[i];
+ struct stp_port *p = stp_get_port(b->stp, i);
+ if (stp_port_get_state(p) == STP_FORWARDING && lan) {
+ dump_lan_tree(tc, lan, level + 1);
+ }
+ }
+}
+
+static void
+dump_lan_tree(struct test_case *tc, struct lan *lan, int level)
+{
+ int i;
+
+ if (lan->reached) {
+ return;
+ }
+ lan->reached = true;
+ for (i = 0; i < level; i++) {
+ printf("\t");
+ }
+ printf("%s\n", lan->name);
+ for (i = 0; i < lan->n_conns; i++) {
+ struct bridge *b = lan->conns[i].bridge;
+ dump_bridge_tree(tc, b, level + 1);
+ }
+}
+
+static void
+tree(struct test_case *tc)
+{
+ int i;
+
+ for (i = 0; i < tc->n_bridges; i++) {
+ struct bridge *b = tc->bridges[i];
+ b->reached = false;
+ }
+ for (i = 0; i < tc->n_lans; i++) {
+ struct lan *lan = tc->lans[i];
+ lan->reached = false;
+ }
+ for (i = 0; i < tc->n_bridges; i++) {
+ struct bridge *b = tc->bridges[i];
+ struct stp *stp = b->stp;
+ if (stp_is_root_bridge(stp)) {
+ dump_bridge_tree(tc, b, 0);
+ }
+ }
+}
+
+static void
+simulate(struct test_case *tc, int granularity)
+{
+ int time;
+
+ for (time = 0; time < 1000 * 180; time += granularity) {
+ int round_trips;
+ int i;
+
+ for (i = 0; i < tc->n_bridges; i++) {
+ stp_tick(tc->bridges[i]->stp, granularity);
+ }
+ for (round_trips = 0; round_trips < granularity; round_trips++) {
+ bool any = false;
+ for (i = 0; i < tc->n_bridges; i++) {
+ struct bridge *b = tc->bridges[i];
+ for (; b->rxq_tail != b->rxq_head; b->rxq_tail++) {
+ struct bpdu *bpdu = &b->rxq[b->rxq_tail % RXQ_SIZE];
+ stp_received_bpdu(stp_get_port(b->stp, bpdu->port_no),
+ bpdu->data, bpdu->size);
+ free(bpdu->data);
+ any = true;
+ }
+ }
+ if (!any) {
+ break;
+ }
+ }
+ }
+}
+
+static void
+err(const char *message, ...)
+ PRINTF_FORMAT(1, 2)
+ NO_RETURN;
+
+static void
+err(const char *message, ...)
+{
+ va_list args;
+
+ fprintf(stderr, "%s:%d:%td: ", file_name, line_number, pos - line);
+ va_start(args, message);
+ vfprintf(stderr, message, args);
+ va_end(args);
+ putc('\n', stderr);
+
+ exit(EXIT_FAILURE);
+}
+
+static void
+warn(const char *message, ...)
+ PRINTF_FORMAT(1, 2);
+
+static void
+warn(const char *message, ...)
+{
+ va_list args;
+
+ fprintf(stderr, "%s:%d: ", file_name, line_number);
+ va_start(args, message);
+ vfprintf(stderr, message, args);
+ va_end(args);
+ putc('\n', stderr);
+
+ n_warnings++;
+}
+
+static bool
+get_token(void)
+{
+ char *start;
+
+ while (isspace((unsigned char) *pos)) {
+ pos++;
+ }
+ if (*pos == '\0') {
+ free(token);
+ token = NULL;
+ return false;
+ }
+
+ start = pos;
+ if (isalpha((unsigned char) *pos)) {
+ while (isalpha((unsigned char) *++pos)) {
+ continue;
+ }
+ } else if (isdigit((unsigned char) *pos)) {
+ if (*pos == '0' && (pos[1] == 'x' || pos[1] == 'X')) {
+ pos += 2;
+ while (isxdigit((unsigned char) *pos)) {
+ pos++;
+ }
+ } else {
+ while (isdigit((unsigned char) *++pos)) {
+ continue;
+ }
+ }
+ } else {
+ pos++;
+ }
+
+ free(token);
+ token = xmemdup0(start, pos - start);
+ return true;
+}
+
+static bool
+get_int(int *intp)
+{
+ char *save_pos = pos;
+ if (token && isdigit((unsigned char) *token)) {
+ *intp = strtol(token, NULL, 0);
+ get_token();
+ return true;
+ } else {
+ pos = save_pos;
+ return false;
+ }
+}
+
+static bool
+match(const char *want)
+{
+ if (token && !strcmp(want, token)) {
+ get_token();
+ return true;
+ } else {
+ return false;
+ }
+}
+
+static int
+must_get_int(void)
+{
+ int x;
+ if (!get_int(&x)) {
+ err("expected integer");
+ }
+ return x;
+}
+
+static void
+must_match(const char *want)
+{
+ if (!match(want)) {
+ err("expected \"%s\"", want);
+ }
+}
+
+int
+main(int argc, char *argv[])
+{
+ struct test_case *tc;
+ FILE *input_file;
+ int i;
+
+ if (argc != 2) {
+ ovs_fatal(0, "usage: test-stp INPUT.STP\n");
+ }
+ file_name = argv[1];
+
+ input_file = fopen(file_name, "r");
+ if (!input_file) {
+ ovs_fatal(errno, "error opening \"%s\"", file_name);
+ }
+
+ tc = new_test_case();
+ for (i = 0; i < 26; i++) {
+ char name[2];
+ name[0] = 'a' + i;
+ name[1] = '\0';
+ new_lan(tc, name);
+ }
+
+ for (line_number = 1; fgets(line, sizeof line, input_file);
+ line_number++)
+ {
+ char *newline, *hash;
+
+ newline = strchr(line, '\n');
+ if (newline) {
+ *newline = '\0';
+ }
+ hash = strchr(line, '#');
+ if (hash) {
+ *hash = '\0';
+ }
+
+ pos = line;
+ if (!get_token()) {
+ continue;
+ }
+ if (match("bridge")) {
+ struct bridge *bridge;
+ int bridge_no, port_no;
+
+ bridge_no = must_get_int();
+ if (bridge_no < tc->n_bridges) {
+ bridge = tc->bridges[bridge_no];
+ } else if (bridge_no == tc->n_bridges) {
+ bridge = new_bridge(tc, must_get_int());
+ } else {
+ err("bridges must be numbered consecutively from 0");
+ }
+ if (match("^")) {
+ stp_set_bridge_priority(bridge->stp, must_get_int());
+ }
+
+ if (match("=")) {
+ for (port_no = 0; port_no < STP_MAX_PORTS; port_no++) {
+ struct stp_port *p = stp_get_port(bridge->stp, port_no);
+ if (!token || match("X")) {
+ stp_port_disable(p);
+ } else if (match("_")) {
+ /* Nothing to do. */
+ } else {
+ struct lan *lan;
+ int path_cost;
+
+ if (!strcmp(token, "0")) {
+ lan = NULL;
+ } else if (strlen(token) == 1
+ && islower((unsigned char)*token)) {
+ lan = tc->lans[*token - 'a'];
+ } else {
+ err("%s is not a valid LAN name "
+ "(0 or a lowercase letter)", token);
+ }
+ get_token();
+
+ path_cost = match(":") ? must_get_int() : 10;
+ if (port_no < bridge->n_ports) {
+ stp_port_set_path_cost(p, path_cost);
+ stp_port_enable(p);
+ reconnect_port(bridge, port_no, lan);
+ } else if (port_no == bridge->n_ports) {
+ new_port(bridge, lan, path_cost);
+ } else {
+ err("ports must be numbered consecutively");
+ }
+ if (match("^")) {
+ stp_port_set_priority(p, must_get_int());
+ }
+ }
+ }
+ }
+ } else if (match("run")) {
+ simulate(tc, must_get_int());
+ } else if (match("dump")) {
+ dump(tc);
+ } else if (match("tree")) {
+ tree(tc);
+ } else if (match("check")) {
+ struct bridge *b;
+ struct stp *stp;
+ int bridge_no, port_no;
+
+ bridge_no = must_get_int();
+ if (bridge_no >= tc->n_bridges) {
+ err("no bridge numbered %d", bridge_no);
+ }
+ b = tc->bridges[bridge_no];
+ stp = b->stp;
+
+ must_match("=");
+
+ if (match("rootid")) {
+ uint64_t rootid;
+ must_match(":");
+ rootid = must_get_int();
+ if (match("^")) {
+ rootid |= (uint64_t) must_get_int() << 48;
+ } else {
+ rootid |= UINT64_C(0x8000) << 48;
+ }
+ if (stp_get_designated_root(stp) != rootid) {
+ warn("%s: root %"PRIx64", not %"PRIx64,
+ stp_get_name(stp), stp_get_designated_root(stp),
+ rootid);
+ }
+ }
+
+ if (match("root")) {
+ if (stp_get_root_path_cost(stp)) {
+ warn("%s: root path cost of root is %u but should be 0",
+ stp_get_name(stp), stp_get_root_path_cost(stp));
+ }
+ if (!stp_is_root_bridge(stp)) {
+ warn("%s: root is %"PRIx64", not %"PRIx64,
+ stp_get_name(stp),
+ stp_get_designated_root(stp), stp_get_bridge_id(stp));
+ }
+ for (port_no = 0; port_no < b->n_ports; port_no++) {
+ struct stp_port *p = stp_get_port(stp, port_no);
+ enum stp_state state = stp_port_get_state(p);
+ if (!(state & (STP_DISABLED | STP_FORWARDING))) {
+ warn("%s: root port %d in state %s",
+ stp_get_name(b->stp), port_no,
+ stp_state_name(state));
+ }
+ }
+ } else {
+ for (port_no = 0; port_no < STP_MAX_PORTS; port_no++) {
+ struct stp_port *p = stp_get_port(stp, port_no);
+ enum stp_state state;
+ if (token == NULL || match("D")) {
+ state = STP_DISABLED;
+ } else if (match("B")) {
+ state = STP_BLOCKING;
+ } else if (match("Li")) {
+ state = STP_LISTENING;
+ } else if (match("Le")) {
+ state = STP_LEARNING;
+ } else if (match("F")) {
+ state = STP_FORWARDING;
+ } else if (match("_")) {
+ continue;
+ } else {
+ err("unknown port state %s", token);
+ }
+ if (stp_port_get_state(p) != state) {
+ warn("%s port %d: state is %s but should be %s",
+ stp_get_name(stp), port_no,
+ stp_state_name(stp_port_get_state(p)),
+ stp_state_name(state));
+ }
+ if (state == STP_FORWARDING) {
+ struct stp_port *root_port = stp_get_root_port(stp);
+ if (match(":")) {
+ int root_path_cost = must_get_int();
+ if (p != root_port) {
+ warn("%s: port %d is not the root port",
+ stp_get_name(stp), port_no);
+ if (!root_port) {
+ warn("%s: (there is no root port)",
+ stp_get_name(stp));
+ } else {
+ warn("%s: (port %d is the root port)",
+ stp_get_name(stp),
+ stp_port_no(root_port));
+ }
+ } else if (root_path_cost
+ != stp_get_root_path_cost(stp)) {
+ warn("%s: root path cost is %u, should be %d",
+ stp_get_name(stp),
+ stp_get_root_path_cost(stp),
+ root_path_cost);
+ }
+ } else if (p == root_port) {
+ warn("%s: port %d is the root port but "
+ "not expected to be",
+ stp_get_name(stp), port_no);
+ }
+ }
+ }
+ }
+ if (n_warnings) {
+ exit(EXIT_FAILURE);
+ }
+ }
+ if (get_token()) {
+ err("trailing garbage on line");
+ }
+ }
+ free(token);
+
+ for (i = 0; i < tc->n_lans; i++) {
+ struct lan *lan = tc->lans[i];
+ free((char *) lan->name);
+ free(lan);
+ }
+ for (i = 0; i < tc->n_bridges; i++) {
+ struct bridge *bridge = tc->bridges[i];
+ stp_destroy(bridge->stp);
+ free(bridge);
+ }
+ free(tc);
+
+ return 0;
+}
projects / openvswitch / commitdiff