X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=secchan%2Fsecchan.c;h=e54fb2ff392d0763b2dc33026af7d648c4f863cb;hb=142f33e8989ab34178e6a04b57f69fff965bd623;hp=25bd794129db7f8b479dd6d58a496d428d3f6214;hpb=648ff09fff8a9b9a10e9f231cb275a57101a89a3;p=sliver-openvswitch.git diff --git a/secchan/secchan.c b/secchan/secchan.c index 25bd79412..e54fb2ff3 100644 --- a/secchan/secchan.c +++ b/secchan/secchan.c @@ -1,6 +1,6 @@ /* Copyright (c) 2008 The Board of Trustees of The Leland Stanford * Junior University - * + * * We are making the OpenFlow specification and associated documentation * (Software) available for public use and benefit with the expectation * that others will use, modify and enhance the Software and contribute @@ -13,10 +13,10 @@ * distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so, subject to * the following conditions: - * + * * The above copyright notice and this permission notice shall be * included in all copies or substantial portions of the Software. - * + * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND @@ -25,15 +25,20 @@ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE * SOFTWARE. - * + * * The name and trademarks of copyright holder(s) may NOT be used in * advertising or publicity pertaining to the Software or any * derivatives without specific, written prior permission. */ +#include +#include #include #include +#include +#include #include +#include #include #include #include @@ -42,101 +47,228 @@ #include "buffer.h" #include "command-line.h" #include "compiler.h" +#include "daemon.h" +#include "dhcp.h" +#include "dhcp-client.h" +#include "dynamic-string.h" #include "fault.h" +#include "flow.h" +#include "learning-switch.h" #include "list.h" -#include "util.h" -#include "rconn.h" -#include "vconn-ssl.h" -#include "vlog-socket.h" +#include "mac-learning.h" +#include "netdev.h" #include "openflow.h" +#include "packets.h" #include "poll-loop.h" +#include "rconn.h" +#include "timeval.h" +#include "util.h" +#include "vconn-ssl.h" #include "vconn.h" +#include "vlog-socket.h" #include "vlog.h" #define THIS_MODULE VLM_secchan -static void parse_options(int argc, char *argv[]); -static void usage(void) NO_RETURN; +/* Behavior when the connection to the controller fails. */ +enum fail_mode { + FAIL_OPEN, /* Act as learning switch. */ + FAIL_CLOSED /* Drop all packets. */ +}; -static const char *listen_vconn_name; +/* Settings that may be configured by the user. */ +struct settings { + /* Overall mode of operation. */ + bool discovery; /* Discover the controller automatically? */ + bool in_band; /* Connect to controller in-band? */ + + /* Related vconns and network devices. */ + const char *nl_name; /* Local datapath (must be "nl:" vconn). */ + char *of_name; /* ofX network device name. */ + const char *controller_name; /* Controller (if not discovery mode). */ + const char *listen_vconn_name; /* Listens for mgmt connections. */ + + /* Failure behavior. */ + enum fail_mode fail_mode; /* Act as learning switch if no controller? */ + int max_idle; /* Idle time for flows in fail-open mode. */ + int probe_interval; /* # seconds idle before sending echo request. */ + int max_backoff; /* Max # seconds between connection attempts. */ + + /* Packet-in rate-limiting. */ + int rate_limit; /* Tokens added to bucket per second. */ + int burst_limit; /* Maximum number token bucket size. */ + + /* Discovery behavior. */ + regex_t accept_controller_regex; /* Controller vconns to accept. */ + const char *accept_controller_re; /* String version of regex. */ + bool update_resolv_conf; /* Update /etc/resolv.conf? */ +}; struct half { struct rconn *rconn; struct buffer *rxbuf; + int n_txq; /* No. of packets queued for tx on 'rconn'. */ }; struct relay { struct list node; + +#define HALF_LOCAL 0 +#define HALF_REMOTE 1 struct half halves[2]; + + bool is_mgmt_conn; +}; + +struct hook { + bool (*packet_cb)(struct relay *, int half, void *aux); + void (*periodic_cb)(void *aux); + void (*wait_cb)(void *aux); + void *aux; }; -static struct list relays = LIST_INITIALIZER(&relays); +static void parse_options(int argc, char *argv[], struct settings *); +static void usage(void) NO_RETURN; -static void new_management_connection(const char *nl_name, struct vconn *new_remote); -static void relay_create(struct rconn *, struct rconn *); -static void relay_run(struct relay *); +static struct relay *relay_create(struct rconn *local, struct rconn *remote, + bool is_mgmt_conn); +static struct relay *relay_accept(const struct settings *, struct vconn *); +static void relay_run(struct relay *, const struct hook[], size_t n_hooks); static void relay_wait(struct relay *); static void relay_destroy(struct relay *); +static struct hook make_hook(bool (*packet_cb)(struct relay *, int, void *), + void (*periodic_cb)(void *), + void (*wait_cb)(void *), + void *aux); + +static struct discovery *discovery_init(const struct settings *); +static void discovery_question_connectivity(struct discovery *); +static bool discovery_run(struct discovery *, char **controller_name); +static void discovery_wait(struct discovery *); + +static struct hook in_band_hook_create(const struct settings *); +static struct hook fail_open_hook_create(const struct settings *, + struct rconn *local, + struct rconn *remote); +static struct hook rate_limit_hook_create(const struct settings *, + struct rconn *local, + struct rconn *remote); + +static void modify_dhcp_request(struct dhcp_msg *, void *aux); +static bool validate_dhcp_offer(const struct dhcp_msg *, void *aux); + int main(int argc, char *argv[]) { + struct settings s; + + struct list relays = LIST_INITIALIZER(&relays); + + struct hook hooks[4]; + size_t n_hooks; + + struct rconn *local_rconn, *remote_rconn; struct vconn *listen_vconn; - const char *nl_name; + struct relay *controller_relay; + struct discovery *discovery; int retval; set_program_name(argv[0]); register_fault_handlers(); + time_init(); vlog_init(); - parse_options(argc, argv); + parse_options(argc, argv, &s); - if (argc - optind != 2) { - fatal(0, - "need exactly two non-option arguments; use --help for usage"); - } - nl_name = argv[optind]; - if (strncmp(nl_name, "nl:", 3) - || strlen(nl_name) < 4 - || nl_name[strspn(nl_name + 3, "0123456789") + 3]) { - fatal(0, "%s: argument is not of the form \"nl:DP_ID\"", nl_name); - } - - if (listen_vconn_name) { - retval = vconn_open(listen_vconn_name, &listen_vconn); + /* Start listening for management connections. */ + if (s.listen_vconn_name) { + retval = vconn_open(s.listen_vconn_name, &listen_vconn); if (retval && retval != EAGAIN) { - fatal(retval, "opening %s", listen_vconn_name); + fatal(retval, "opening %s", s.listen_vconn_name); } if (!vconn_is_passive(listen_vconn)) { - fatal(0, "%s is not a passive vconn", listen_vconn_name); + fatal(0, "%s is not a passive vconn", s.listen_vconn_name); } } else { listen_vconn = NULL; } + /* Start controller discovery. */ + discovery = s.discovery ? discovery_init(&s) : NULL; + + /* Start listening for vlogconf requests. */ retval = vlog_server_listen(NULL, NULL); if (retval) { fatal(retval, "Could not listen for vlog connections"); } - relay_create(rconn_new(argv[optind], 1), rconn_new(argv[optind + 1], 1)); + daemonize(); + + /* Connect to datapath. */ + local_rconn = rconn_create(0, s.max_backoff); + rconn_connect(local_rconn, s.nl_name); + + /* Connect to controller. */ + remote_rconn = rconn_create(s.probe_interval, s.max_backoff); + if (s.controller_name) { + retval = rconn_connect(remote_rconn, s.controller_name); + if (retval == EAFNOSUPPORT) { + fatal(0, "No support for %s vconn", s.controller_name); + } + } + + /* Start relaying. */ + controller_relay = relay_create(local_rconn, remote_rconn, false); + list_push_back(&relays, &controller_relay->node); + + /* Set up hooks. */ + n_hooks = 0; + if (s.in_band) { + hooks[n_hooks++] = in_band_hook_create(&s); + } + if (s.fail_mode == FAIL_OPEN) { + hooks[n_hooks++] = fail_open_hook_create(&s, + local_rconn, remote_rconn); + } + if (s.rate_limit) { + hooks[n_hooks++] = rate_limit_hook_create(&s, + local_rconn, remote_rconn); + } + assert(n_hooks <= ARRAY_SIZE(hooks)); + for (;;) { struct relay *r, *n; + size_t i; /* Do work. */ LIST_FOR_EACH_SAFE (r, n, struct relay, node, &relays) { - relay_run(r); + relay_run(r, hooks, n_hooks); } if (listen_vconn) { for (;;) { - struct vconn *new_remote; - retval = vconn_accept(listen_vconn, &new_remote); - if (retval) { - if (retval != EAGAIN) { - VLOG_WARN("accept failed (%s)", strerror(retval)); - } + struct relay *r = relay_accept(&s, listen_vconn); + if (!r) { break; } - new_management_connection(nl_name, new_remote); + list_push_back(&relays, &r->node); + } + } + for (i = 0; i < n_hooks; i++) { + if (hooks[i].periodic_cb) { + hooks[i].periodic_cb(hooks[i].aux); + } + } + if (s.discovery) { + char *controller_name; + if (rconn_is_connectivity_questionable(remote_rconn)) { + discovery_question_connectivity(discovery); + } + if (discovery_run(discovery, &controller_name)) { + if (controller_name) { + rconn_connect(remote_rconn, controller_name); + } else { + rconn_disconnect(remote_rconn); + } } } @@ -147,58 +279,91 @@ main(int argc, char *argv[]) if (listen_vconn) { vconn_accept_wait(listen_vconn); } + for (i = 0; i < n_hooks; i++) { + if (hooks[i].wait_cb) { + hooks[i].wait_cb(hooks[i].aux); + } + } + if (discovery) { + discovery_wait(discovery); + } poll_block(); } return 0; } -static void -new_management_connection(const char *nl_name, struct vconn *new_remote) +static struct hook +make_hook(bool (*packet_cb)(struct relay *, int half, void *aux), + void (*periodic_cb)(void *aux), + void (*wait_cb)(void *aux), + void *aux) { + struct hook h; + h.packet_cb = packet_cb; + h.periodic_cb = periodic_cb; + h.wait_cb = wait_cb; + h.aux = aux; + return h; +} + +/* OpenFlow message relaying. */ + +static struct relay * +relay_accept(const struct settings *s, struct vconn *listen_vconn) +{ + struct vconn *new_remote, *new_local; char *nl_name_without_subscription; - struct vconn *new_local; struct rconn *r1, *r2; int retval; + retval = vconn_accept(listen_vconn, &new_remote); + if (retval) { + if (retval != EAGAIN) { + VLOG_WARN("accept failed (%s)", strerror(retval)); + } + return NULL; + } + /* nl:123 or nl:123:1 opens a netlink connection to local datapath 123. We * only accept the former syntax in main(). * * nl:123:0 opens a netlink connection to local datapath 123 without * obtaining a subscription for ofp_packet_in or ofp_flow_expired * messages.*/ - nl_name_without_subscription = xasprintf("%s:0", nl_name); + nl_name_without_subscription = xasprintf("%s:0", s->nl_name); retval = vconn_open(nl_name_without_subscription, &new_local); if (retval) { VLOG_ERR("could not connect to %s (%s)", nl_name_without_subscription, strerror(retval)); vconn_close(new_remote); - return; + free(nl_name_without_subscription); + return NULL; } + + /* Create and return relay. */ + r1 = rconn_create(0, 0); + rconn_connect_unreliably(r1, nl_name_without_subscription, new_local); free(nl_name_without_subscription); - /* Add it to the relay list. */ - r1 = rconn_new_from_vconn(nl_name_without_subscription, 1, new_local); - r2 = rconn_new_from_vconn("passive", 1, new_remote); - relay_create(r1, r2); + r2 = rconn_create(0, 0); + rconn_connect_unreliably(r2, "passive", new_remote); + + return relay_create(r1, r2, true); } -static void -relay_create(struct rconn *a, struct rconn *b) +static struct relay * +relay_create(struct rconn *local, struct rconn *remote, bool is_mgmt_conn) { - struct relay *r; - int i; - - r = xmalloc(sizeof *r); - for (i = 0; i < 2; i++) { - r->halves[i].rconn = i ? b : a; - r->halves[i].rxbuf = NULL; - } - list_push_back(&relays, &r->node); + struct relay *r = xcalloc(1, sizeof *r); + r->halves[HALF_LOCAL].rconn = local; + r->halves[HALF_REMOTE].rconn = remote; + r->is_mgmt_conn = is_mgmt_conn; + return r; } static void -relay_run(struct relay *r) +relay_run(struct relay *r, const struct hook hooks[], size_t n_hooks) { int iteration; int i; @@ -216,10 +381,22 @@ relay_run(struct relay *r) if (!this->rxbuf) { this->rxbuf = rconn_recv(this->rconn); + if (this->rxbuf) { + const struct hook *h; + for (h = hooks; h < &hooks[n_hooks]; h++) { + if (h->packet_cb(r, i, h->aux)) { + buffer_delete(this->rxbuf); + this->rxbuf = NULL; + progress = true; + break; + } + } + } } - if (this->rxbuf) { - int retval = rconn_send(peer->rconn, this->rxbuf); + if (this->rxbuf && !this->n_txq) { + int retval = rconn_send(peer->rconn, this->rxbuf, + &this->n_txq); if (retval != EAGAIN) { if (!retval) { progress = true; @@ -235,11 +412,13 @@ relay_run(struct relay *r) } } - for (i = 0; i < 2; i++) { - struct half *this = &r->halves[i]; - if (!rconn_is_alive(this->rconn)) { - relay_destroy(r); - return; + if (r->is_mgmt_conn) { + for (i = 0; i < 2; i++) { + struct half *this = &r->halves[i]; + if (!rconn_is_alive(this->rconn)) { + relay_destroy(r); + return; + } } } } @@ -272,12 +451,581 @@ relay_destroy(struct relay *r) } free(r); } + +/* In-band control. */ + +struct in_band_data { + const struct settings *s; + struct mac_learning *ml; + struct netdev *of_device; + uint8_t mac[ETH_ADDR_LEN]; + int n_queued; +}; + +static void +queue_tx(struct rconn *rc, struct in_band_data *in_band, struct buffer *b) +{ + rconn_send_with_limit(rc, b, &in_band->n_queued, 10); +} + +static const uint8_t * +get_controller_mac(struct netdev *netdev, struct rconn *controller) +{ + static uint32_t ip, last_nonzero_ip; + static uint8_t mac[ETH_ADDR_LEN], last_nonzero_mac[ETH_ADDR_LEN]; + static time_t next_refresh = 0; + + uint32_t last_ip = ip; + + time_t now = time_now(); + + ip = rconn_get_ip(controller); + if (last_ip != ip || !next_refresh || now >= next_refresh) { + bool have_mac; + + /* Look up MAC address. */ + memset(mac, 0, sizeof mac); + if (ip) { + int retval = netdev_arp_lookup(netdev, ip, mac); + if (retval) { + VLOG_DBG("cannot look up controller hw address ("IP_FMT"): %s", + IP_ARGS(&ip), strerror(retval)); + } + } + have_mac = !eth_addr_is_zero(mac); + + /* Log changes in IP, MAC addresses. */ + if (ip && ip != last_nonzero_ip) { + VLOG_DBG("controller IP address changed from "IP_FMT + " to "IP_FMT, IP_ARGS(&last_nonzero_ip), IP_ARGS(&ip)); + last_nonzero_ip = ip; + } + if (have_mac && memcmp(last_nonzero_mac, mac, ETH_ADDR_LEN)) { + VLOG_DBG("controller MAC address changed from "ETH_ADDR_FMT" to " + ETH_ADDR_FMT, + ETH_ADDR_ARGS(last_nonzero_mac), ETH_ADDR_ARGS(mac)); + memcpy(last_nonzero_mac, mac, ETH_ADDR_LEN); + } + + /* Schedule next refresh. + * + * If we have an IP address but not a MAC address, then refresh + * quickly, since we probably will get a MAC address soon (via ARP). + * Otherwise, we can afford to wait a little while. */ + next_refresh = now + (!ip || have_mac ? 10 : 1); + } + return !eth_addr_is_zero(mac) ? mac : NULL; +} + +static bool +is_controller_mac(const uint8_t mac[ETH_ADDR_LEN], + const uint8_t *controller_mac) +{ + return controller_mac && eth_addr_equals(mac, controller_mac); +} + +static bool +in_band_packet_cb(struct relay *r, int half, void *in_band_) +{ + struct in_band_data *in_band = in_band_; + struct rconn *rc = r->halves[HALF_LOCAL].rconn; + struct buffer *msg = r->halves[HALF_LOCAL].rxbuf; + struct ofp_packet_in *opi; + struct ofp_header *oh; + size_t pkt_ofs, pkt_len; + struct buffer pkt; + struct flow flow; + uint16_t in_port, out_port; + const uint8_t *controller_mac; + + if (half != HALF_LOCAL || r->is_mgmt_conn) { + return false; + } + + oh = msg->data; + if (oh->type != OFPT_PACKET_IN) { + return false; + } + if (msg->size < offsetof (struct ofp_packet_in, data)) { + VLOG_WARN("packet too short (%zu bytes) for packet_in", msg->size); + return false; + } + + /* Extract flow data from 'opi' into 'flow'. */ + opi = msg->data; + in_port = ntohs(opi->in_port); + pkt_ofs = offsetof(struct ofp_packet_in, data); + pkt_len = ntohs(opi->header.length) - pkt_ofs; + pkt.data = opi->data; + pkt.size = pkt_len; + flow_extract(&pkt, in_port, &flow); + + /* Deal with local stuff. */ + controller_mac = get_controller_mac(in_band->of_device, + r->halves[HALF_REMOTE].rconn); + if (in_port == OFPP_LOCAL) { + /* Sent by secure channel. */ + out_port = mac_learning_lookup(in_band->ml, flow.dl_dst); + } else if (eth_addr_equals(flow.dl_dst, in_band->mac)) { + /* Sent to secure channel. */ + out_port = OFPP_LOCAL; + if (mac_learning_learn(in_band->ml, flow.dl_src, in_port)) { + VLOG_DBG("learned that "ETH_ADDR_FMT" is on port %"PRIu16, + ETH_ADDR_ARGS(flow.dl_src), in_port); + } + } else if (flow.dl_type == htons(ETH_TYPE_ARP) + && eth_addr_is_broadcast(flow.dl_dst) + && is_controller_mac(flow.dl_src, controller_mac)) { + /* ARP sent by controller. */ + out_port = OFPP_FLOOD; + } else if (is_controller_mac(flow.dl_dst, controller_mac) + && in_port == mac_learning_lookup(in_band->ml, + controller_mac)) { + /* Drop controller traffic that arrives on the controller port. */ + queue_tx(rc, in_band, make_add_flow(&flow, ntohl(opi->buffer_id), + in_band->s->max_idle, 0)); + return true; + } else { + return false; + } + + if (out_port != OFPP_FLOOD) { + /* The output port is known, so add a new flow. */ + queue_tx(rc, in_band, + make_add_simple_flow(&flow, ntohl(opi->buffer_id), + out_port, in_band->s->max_idle)); + + /* If the switch didn't buffer the packet, we need to send a copy. */ + if (ntohl(opi->buffer_id) == UINT32_MAX) { + queue_tx(rc, in_band, + make_unbuffered_packet_out(&pkt, in_port, out_port)); + } + } else { + /* We don't know that MAC. Send along the packet without setting up a + * flow. */ + struct buffer *b; + if (ntohl(opi->buffer_id) == UINT32_MAX) { + b = make_unbuffered_packet_out(&pkt, in_port, out_port); + } else { + b = make_buffered_packet_out(ntohl(opi->buffer_id), + in_port, out_port); + } + queue_tx(rc, in_band, b); + } + return true; +} + +static struct hook +in_band_hook_create(const struct settings *s) +{ + struct in_band_data *in_band; + int retval; + + in_band = xcalloc(1, sizeof *in_band); + in_band->s = s; + in_band->ml = mac_learning_create(); + retval = netdev_open(s->of_name, NETDEV_ETH_TYPE_NONE, + &in_band->of_device); + if (retval) { + fatal(retval, "Could not open %s device", s->of_name); + } + memcpy(in_band->mac, netdev_get_etheraddr(in_band->of_device), + ETH_ADDR_LEN); + + return make_hook(in_band_packet_cb, NULL, NULL, in_band); +} + +/* Fail open support. */ + +struct fail_open_data { + const struct settings *s; + struct rconn *local_rconn; + struct rconn *remote_rconn; + struct lswitch *lswitch; + int last_disconn_secs; +}; + +/* Causes 'r' to enter or leave fail-open mode, if appropriate. */ +static void +fail_open_periodic_cb(void *fail_open_) +{ + struct fail_open_data *fail_open = fail_open_; + int disconn_secs; + bool open; + + disconn_secs = rconn_disconnected_duration(fail_open->remote_rconn); + open = disconn_secs >= fail_open->s->probe_interval * 3; + if (open != (fail_open->lswitch != NULL)) { + if (!open) { + VLOG_WARN("No longer in fail-open mode"); + lswitch_destroy(fail_open->lswitch); + fail_open->lswitch = NULL; + } else { + VLOG_WARN("Could not connect to controller for %d seconds, " + "failing open", disconn_secs); + fail_open->lswitch = lswitch_create(fail_open->local_rconn, true, + fail_open->s->max_idle); + fail_open->last_disconn_secs = disconn_secs; + } + } else if (open && disconn_secs > fail_open->last_disconn_secs + 60) { + VLOG_WARN("Still in fail-open mode after %d seconds disconnected " + "from controller", disconn_secs); + fail_open->last_disconn_secs = disconn_secs; + } +} + +static bool +fail_open_packet_cb(struct relay *r, int half, void *fail_open_) +{ + struct fail_open_data *fail_open = fail_open_; + if (half != HALF_LOCAL || r->is_mgmt_conn || !fail_open->lswitch) { + return false; + } else { + lswitch_process_packet(fail_open->lswitch, fail_open->local_rconn, + r->halves[HALF_LOCAL].rxbuf); + rconn_run(fail_open->local_rconn); + return true; + } +} + +static struct hook +fail_open_hook_create(const struct settings *s, struct rconn *local_rconn, + struct rconn *remote_rconn) +{ + struct fail_open_data *fail_open = xmalloc(sizeof *fail_open); + fail_open->s = s; + fail_open->local_rconn = local_rconn; + fail_open->remote_rconn = remote_rconn; + fail_open->lswitch = NULL; + return make_hook(fail_open_packet_cb, fail_open_periodic_cb, NULL, + fail_open); +} + +struct rate_limiter { + const struct settings *s; + struct rconn *remote_rconn; + + /* One queue per physical port. */ + struct queue queues[OFPP_MAX]; + int n_queued; /* Sum over queues[*].n. */ + int next_tx_port; /* Next port to check in round-robin. */ + + /* Token bucket. + * + * It costs 1000 tokens to send a single packet_in message. A single token + * per message would be more straightforward, but this choice lets us avoid + * round-off error in refill_bucket()'s calculation of how many tokens to + * add to the bucket, since no division step is needed. */ + long long int last_fill; /* Time at which we last added tokens. */ + int tokens; /* Current number of tokens. */ + + /* Transmission queue. */ + int n_txq; /* No. of packets waiting in rconn for tx. */ +}; + +/* Drop a packet from the longest queue in 'rl'. */ +static void +drop_packet(struct rate_limiter *rl) +{ + struct queue *longest; /* Queue currently selected as longest. */ + int n_longest; /* # of queues of same length as 'longest'. */ + struct queue *q; + + longest = &rl->queues[0]; + n_longest = 1; + for (q = &rl->queues[0]; q < &rl->queues[OFPP_MAX]; q++) { + if (longest->n < q->n) { + longest = q; + n_longest = 1; + } else if (longest->n == q->n) { + n_longest++; + + /* Randomly select one of the longest queues, with a uniform + * distribution (Knuth algorithm 3.4.2R). */ + if (!random_range(n_longest)) { + longest = q; + } + } + } + + /* FIXME: do we want to pop the tail instead? */ + buffer_delete(queue_pop_head(longest)); + rl->n_queued--; +} + +/* Remove and return the next packet to transmit (in round-robin order). */ +static struct buffer * +dequeue_packet(struct rate_limiter *rl) +{ + unsigned int i; + + for (i = 0; i < OFPP_MAX; i++) { + unsigned int port = (rl->next_tx_port + i) % OFPP_MAX; + struct queue *q = &rl->queues[port]; + if (q->n) { + rl->next_tx_port = (port + 1) % OFPP_MAX; + rl->n_queued--; + return queue_pop_head(q); + } + } + NOT_REACHED(); +} + +/* Add tokens to the bucket based on elapsed time. */ +static void +refill_bucket(struct rate_limiter *rl) +{ + const struct settings *s = rl->s; + long long int now = time_msec(); + long long int tokens = (now - rl->last_fill) * s->rate_limit + rl->tokens; + if (tokens >= 1000) { + rl->last_fill = now; + rl->tokens = MIN(tokens, s->burst_limit * 1000); + } +} + +/* Attempts to remove enough tokens from 'rl' to transmit a packet. Returns + * true if successful, false otherwise. (In the latter case no tokens are + * removed.) */ +static bool +get_token(struct rate_limiter *rl) +{ + if (rl->tokens >= 1000) { + rl->tokens -= 1000; + return true; + } else { + return false; + } +} + +static bool +rate_limit_packet_cb(struct relay *r, int half, void *rl_) +{ + struct rate_limiter *rl = rl_; + const struct settings *s = rl->s; + struct buffer *msg = r->halves[HALF_LOCAL].rxbuf; + struct ofp_header *oh; + + if (half == HALF_REMOTE) { + return false; + } + + oh = msg->data; + if (oh->type != OFPT_PACKET_IN) { + return false; + } + if (msg->size < offsetof(struct ofp_packet_in, data)) { + VLOG_WARN("packet too short (%zu bytes) for packet_in", msg->size); + return false; + } + + if (!rl->n_queued && get_token(rl)) { + /* In the common case where we are not constrained by the rate limit, + * let the packet take the normal path. */ + return false; + } else { + /* Otherwise queue it up for the periodic callback to drain out. */ + struct ofp_packet_in *opi = msg->data; + int port = ntohs(opi->in_port) % OFPP_MAX; + if (rl->n_queued >= s->burst_limit) { + drop_packet(rl); + } + queue_push_tail(&rl->queues[port], buffer_clone(msg)); + rl->n_queued++; + return true; + } +} static void -parse_options(int argc, char *argv[]) +rate_limit_periodic_cb(void *rl_) { + struct rate_limiter *rl = rl_; + int i; + + /* Drain some packets out of the bucket if possible, but limit the number + * of iterations to allow other code to get work done too. */ + refill_bucket(rl); + for (i = 0; rl->n_queued && get_token(rl) && i < 50; i++) { + /* Use a small, arbitrary limit for the amount of queuing to do here, + * because the TCP connection is responsible for buffering and there is + * no point in trying to transmit faster than the TCP connection can + * handle. */ + struct buffer *b = dequeue_packet(rl); + rconn_send_with_limit(rl->remote_rconn, b, &rl->n_txq, 10); + } +} + +static void +rate_limit_wait_cb(void *rl_) +{ + struct rate_limiter *rl = rl_; + if (rl->n_queued) { + if (rl->tokens >= 1000) { + /* We can transmit more packets as soon as we're called again. */ + poll_immediate_wake(); + } else { + /* We have to wait for the bucket to re-fill. We could calculate + * the exact amount of time here for increased smoothness. */ + poll_timer_wait(TIME_UPDATE_INTERVAL / 2); + } + } +} + +static struct hook +rate_limit_hook_create(const struct settings *s, + struct rconn *local, + struct rconn *remote) +{ + struct rate_limiter *rl; + size_t i; + + rl = xcalloc(1, sizeof *rl); + rl->s = s; + rl->remote_rconn = remote; + for (i = 0; i < ARRAY_SIZE(rl->queues); i++) { + queue_init(&rl->queues[i]); + } + rl->last_fill = time_msec(); + rl->tokens = s->rate_limit * 100; + return make_hook(rate_limit_packet_cb, rate_limit_periodic_cb, + rate_limit_wait_cb, rl); +} + +/* Controller discovery. */ + +struct discovery +{ + const struct settings *s; + struct dhclient *dhcp; + bool ever_successful; +}; + +static struct discovery * +discovery_init(const struct settings *s) +{ + struct netdev *netdev; + struct discovery *d; + struct dhclient *dhcp; + int retval; + + /* Bring ofX network device up. */ + retval = netdev_open(s->of_name, NETDEV_ETH_TYPE_NONE, &netdev); + if (retval) { + fatal(retval, "Could not open %s device", s->of_name); + } + retval = netdev_turn_flags_on(netdev, NETDEV_UP, true); + if (retval) { + fatal(retval, "Could not bring %s device up", s->of_name); + } + netdev_close(netdev); + + /* Initialize DHCP client. */ + retval = dhclient_create(s->of_name, modify_dhcp_request, + validate_dhcp_offer, (void *) s, &dhcp); + if (retval) { + fatal(retval, "Failed to initialize DHCP client"); + } + dhclient_init(dhcp, 0); + + d = xmalloc(sizeof *d); + d->s = s; + d->dhcp = dhcp; + d->ever_successful = false; + return d; +} + +static void +discovery_question_connectivity(struct discovery *d) +{ + dhclient_force_renew(d->dhcp, 15); +} + +static bool +discovery_run(struct discovery *d, char **controller_name) +{ + dhclient_run(d->dhcp); + if (!dhclient_changed(d->dhcp)) { + return false; + } + + dhclient_configure_netdev(d->dhcp); + if (d->s->update_resolv_conf) { + dhclient_update_resolv_conf(d->dhcp); + } + + if (dhclient_is_bound(d->dhcp)) { + *controller_name = dhcp_msg_get_string(dhclient_get_config(d->dhcp), + DHCP_CODE_OFP_CONTROLLER_VCONN); + VLOG_WARN("%s: discovered controller", *controller_name); + d->ever_successful = true; + } else if (controller_name) { + *controller_name = NULL; + if (d->ever_successful) { + VLOG_WARN("discovered controller no longer available"); + } + } + return true; +} + +static void +discovery_wait(struct discovery *d) +{ + dhclient_wait(d->dhcp); +} + +static void +modify_dhcp_request(struct dhcp_msg *msg, void *aux) +{ + dhcp_msg_put_string(msg, DHCP_CODE_VENDOR_CLASS, "OpenFlow"); +} + +static bool +validate_dhcp_offer(const struct dhcp_msg *msg, void *s_) +{ + const struct settings *s = s_; + char *vconn_name; + bool accept; + + vconn_name = dhcp_msg_get_string(msg, DHCP_CODE_OFP_CONTROLLER_VCONN); + if (!vconn_name) { + VLOG_WARN("rejecting DHCP offer missing controller vconn"); + return false; + } + accept = !regexec(&s->accept_controller_regex, vconn_name, 0, NULL, 0); + if (!accept) { + VLOG_WARN("rejecting controller vconn that fails to match %s", + s->accept_controller_re); + } + free(vconn_name); + return accept; +} + +/* User interface. */ + +static void +parse_options(int argc, char *argv[], struct settings *s) +{ + enum { + OPT_ACCEPT_VCONN = UCHAR_MAX + 1, + OPT_NO_RESOLV_CONF, + OPT_INACTIVITY_PROBE, + OPT_MAX_IDLE, + OPT_MAX_BACKOFF, + OPT_RATE_LIMIT, + OPT_BURST_LIMIT + }; static struct option long_options[] = { + {"accept-vconn", required_argument, 0, OPT_ACCEPT_VCONN}, + {"no-resolv-conf", no_argument, 0, OPT_NO_RESOLV_CONF}, + {"fail", required_argument, 0, 'f'}, + {"inactivity-probe", required_argument, 0, OPT_INACTIVITY_PROBE}, + {"max-idle", required_argument, 0, OPT_MAX_IDLE}, + {"max-backoff", required_argument, 0, OPT_MAX_BACKOFF}, {"listen", required_argument, 0, 'l'}, + {"rate-limit", optional_argument, 0, OPT_RATE_LIMIT}, + {"burst-limit", required_argument, 0, OPT_BURST_LIMIT}, + {"detach", no_argument, 0, 'D'}, + {"pidfile", optional_argument, 0, 'P'}, {"verbose", optional_argument, 0, 'v'}, {"help", no_argument, 0, 'h'}, {"version", no_argument, 0, 'V'}, @@ -285,7 +1033,18 @@ parse_options(int argc, char *argv[]) {0, 0, 0, 0}, }; char *short_options = long_options_to_short_options(long_options); - + char *accept_re = NULL; + int retval; + + /* Set defaults that we can figure out before parsing options. */ + s->listen_vconn_name = NULL; + s->fail_mode = FAIL_OPEN; + s->max_idle = 15; + s->probe_interval = 15; + s->max_backoff = 15; + s->update_resolv_conf = true; + s->rate_limit = 0; + s->burst_limit = 0; for (;;) { int c; @@ -295,11 +1054,84 @@ parse_options(int argc, char *argv[]) } switch (c) { + case OPT_ACCEPT_VCONN: + accept_re = optarg[0] == '^' ? optarg : xasprintf("^%s", optarg); + break; + + case OPT_NO_RESOLV_CONF: + s->update_resolv_conf = false; + break; + + case 'f': + if (!strcmp(optarg, "open")) { + s->fail_mode = FAIL_OPEN; + } else if (!strcmp(optarg, "closed")) { + s->fail_mode = FAIL_CLOSED; + } else { + fatal(0, + "-f or --fail argument must be \"open\" or \"closed\""); + } + break; + + case OPT_INACTIVITY_PROBE: + s->probe_interval = atoi(optarg); + if (s->probe_interval < 5) { + fatal(0, "--inactivity-probe argument must be at least 5"); + } + break; + + case OPT_MAX_IDLE: + if (!strcmp(optarg, "permanent")) { + s->max_idle = OFP_FLOW_PERMANENT; + } else { + s->max_idle = atoi(optarg); + if (s->max_idle < 1 || s->max_idle > 65535) { + fatal(0, "--max-idle argument must be between 1 and " + "65535 or the word 'permanent'"); + } + } + break; + + case OPT_MAX_BACKOFF: + s->max_backoff = atoi(optarg); + if (s->max_backoff < 1) { + fatal(0, "--max-backoff argument must be at least 1"); + } else if (s->max_backoff > 3600) { + s->max_backoff = 3600; + } + break; + + case OPT_RATE_LIMIT: + if (optarg) { + s->rate_limit = atoi(optarg); + if (s->rate_limit < 1) { + fatal(0, "--rate-limit argument must be at least 1"); + } + } else { + s->rate_limit = 1000; + } + break; + + case OPT_BURST_LIMIT: + s->burst_limit = atoi(optarg); + if (s->burst_limit < 1) { + fatal(0, "--burst-limit argument must be at least 1"); + } + break; + + case 'D': + set_detach(); + break; + + case 'P': + set_pidfile(optarg); + break; + case 'l': - if (listen_vconn_name) { + if (s->listen_vconn_name) { fatal(0, "-l or --listen may be only specified once"); } - listen_vconn_name = optarg; + s->listen_vconn_name = optarg; break; case 'h': @@ -323,22 +1155,114 @@ parse_options(int argc, char *argv[]) } } free(short_options); + + argc -= optind; + argv += optind; + if (argc < 1 || argc > 2) { + fatal(0, "need one or two non-option arguments; use --help for usage"); + } + + /* Local and remote vconns. */ + s->nl_name = argv[0]; + if (strncmp(s->nl_name, "nl:", 3) + || strlen(s->nl_name) < 4 + || s->nl_name[strspn(s->nl_name + 3, "0123456789") + 3]) { + fatal(0, "%s: argument is not of the form \"nl:DP_IDX\"", s->nl_name); + } + s->of_name = xasprintf("of%s", s->nl_name + 3); + s->controller_name = argc > 1 ? xstrdup(argv[1]) : NULL; + + /* Set accept_controller_regex. */ + if (!accept_re) { + accept_re = vconn_ssl_is_configured() ? "^ssl:.*" : ".*"; + } + retval = regcomp(&s->accept_controller_regex, accept_re, + REG_NOSUB | REG_EXTENDED); + if (retval) { + size_t length = regerror(retval, &s->accept_controller_regex, NULL, 0); + char *buffer = xmalloc(length); + regerror(retval, &s->accept_controller_regex, buffer, length); + fatal(0, "%s: %s", accept_re, buffer); + } + s->accept_controller_re = accept_re; + + /* Mode of operation. */ + s->discovery = s->controller_name == NULL; + if (s->discovery) { + s->in_band = true; + } else { + enum netdev_flags flags; + struct netdev *netdev; + + retval = netdev_open(s->of_name, NETDEV_ETH_TYPE_NONE, &netdev); + if (retval) { + fatal(retval, "Could not open %s device", s->of_name); + } + + retval = netdev_get_flags(netdev, &flags); + if (retval) { + fatal(retval, "Could not get flags for %s device", s->of_name); + } + + s->in_band = (flags & NETDEV_UP) != 0; + if (s->in_band && netdev_get_in6(netdev, NULL)) { + VLOG_WARN("Ignoring IPv6 address on %s device: IPv6 not supported", + s->of_name); + } + + netdev_close(netdev); + } + + /* Rate limiting. */ + if (s->rate_limit) { + if (s->rate_limit < 100) { + VLOG_WARN("Rate limit set to unusually low value %d", + s->rate_limit); + } + + if (!s->burst_limit) { + s->burst_limit = s->rate_limit * 2; + } else if (s->burst_limit < s->rate_limit) { + VLOG_WARN("Burst limit (%d) set lower than rate limit (%d)", + s->burst_limit, s->rate_limit); + } + s->burst_limit = MIN(s->burst_limit, INT_MAX / 1000); + } } static void usage(void) { - printf("%s: Secure Channel, a relay for OpenFlow messages.\n" - "usage: %s [OPTIONS] LOCAL REMOTE\n" - "where LOCAL and REMOTE are active OpenFlow connection methods.\n", + printf("%s: secure channel, a relay for OpenFlow messages.\n" + "usage: %s [OPTIONS] nl:DP_IDX [CONTROLLER]\n" + "where nl:DP_IDX is a datapath that has been added with dpctl.\n" + "CONTROLLER is an active OpenFlow connection method; if it is\n" + "omitted, then secchan performs controller discovery.\n", program_name, program_name); vconn_usage(true, true); - printf("\nNetworking options:\n" + printf("\nController discovery options:\n" + " --accept-vconn=REGEX accept matching discovered controllers\n" + " --no-resolv-conf do not update /etc/resolv.conf\n" + "\nNetworking options:\n" + " -f, --fail=open|closed when controller connection fails:\n" + " closed: drop all packets\n" + " open (default): act as learning switch\n" + " --inactivity-probe=SECS time between inactivity probes\n" + " --max-idle=SECS max idle for flows set up by secchan\n" + " --max-backoff=SECS max time between controller connection\n" + " attempts (default: 15 seconds)\n" " -l, --listen=METHOD allow management connections on METHOD\n" " (a passive OpenFlow connection method)\n" + "\nRate-limiting of \"packet-in\" messages to the controller:\n" + " --rate-limit[=PACKETS] max rate, in packets/s (default: 1000)\n" + " --burst-limit=BURST limit on packet credit for idle time\n" "\nOther options:\n" + " -D, --detach run in background as daemon\n" + " -P, --pidfile[=FILE] create pidfile (default: %s/secchan.pid)\n" + " -v, --verbose=MODULE[:FACILITY[:LEVEL]] set logging levels\n" " -v, --verbose set maximum verbosity level\n" " -h, --help display this help message\n" - " -V, --version display version information\n"); + " -V, --version display version information\n", + RUNDIR); exit(EXIT_SUCCESS); }