[ovs.git] / lib / ofp-print.c

/*
 * 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 "ofp-print.h"

#include <errno.h>
#include <inttypes.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <sys/wait.h>
#include <stdarg.h>
#include <stdlib.h>
#include <ctype.h>

#include "byte-order.h"
#include "compiler.h"
#include "dynamic-string.h"
#include "flow.h"
#include "nx-match.h"
#include "ofp-util.h"
#include "ofpbuf.h"
#include "openflow/openflow.h"
#include "openflow/nicira-ext.h"
#include "packets.h"
#include "pcap.h"
#include "util.h"

static void ofp_print_port_name(struct ds *string, uint16_t port);
static void ofp_print_queue_name(struct ds *string, uint32_t port);
static void ofp_print_error(struct ds *, int error);


/* Returns a string that represents the contents of the Ethernet frame in the
 * 'len' bytes starting at 'data' to 'stream' as output by tcpdump.
 * 'total_len' specifies the full length of the Ethernet frame (of which 'len'
 * bytes were captured).
 *
 * The caller must free the returned string.
 *
 * This starts and kills a tcpdump subprocess so it's quite expensive. */
char *
ofp_packet_to_string(const void *data, size_t len, size_t total_len OVS_UNUSED)
{
    struct ds ds = DS_EMPTY_INITIALIZER;
    struct ofpbuf buf;

    char command[128];
    FILE *pcap;
    FILE *tcpdump;
    int status;
    int c;

    ofpbuf_use_const(&buf, data, len);

    pcap = tmpfile();
    if (!pcap) {
        ovs_error(errno, "tmpfile");
        return xstrdup("<error>");
    }
    pcap_write_header(pcap);
    pcap_write(pcap, &buf);
    fflush(pcap);
    if (ferror(pcap)) {
        ovs_error(errno, "error writing temporary file");
    }
    rewind(pcap);

    snprintf(command, sizeof command, "/usr/sbin/tcpdump -e -n -r /dev/fd/%d 2>/dev/null",
             fileno(pcap));
    tcpdump = popen(command, "r");
    fclose(pcap);
    if (!tcpdump) {
        ovs_error(errno, "exec(\"%s\")", command);
        return xstrdup("<error>");
    }

    while ((c = getc(tcpdump)) != EOF) {
        ds_put_char(&ds, c);
    }

    status = pclose(tcpdump);
    if (WIFEXITED(status)) {
        if (WEXITSTATUS(status))
            ovs_error(0, "tcpdump exited with status %d", WEXITSTATUS(status));
    } else if (WIFSIGNALED(status)) {
        ovs_error(0, "tcpdump exited with signal %d", WTERMSIG(status));
    }
    return ds_cstr(&ds);
}

static void
ofp_print_packet_in(struct ds *string, const struct ofp_packet_in *op,
                    int verbosity)
{
    size_t len = ntohs(op->header.length);
    size_t data_len;

    ds_put_format(string, " total_len=%"PRIu16" in_port=",
                  ntohs(op->total_len));
    ofp_print_port_name(string, ntohs(op->in_port));

    if (op->reason == OFPR_ACTION)
        ds_put_cstr(string, " (via action)");
    else if (op->reason != OFPR_NO_MATCH)
        ds_put_format(string, " (***reason %"PRIu8"***)", op->reason);

    data_len = len - offsetof(struct ofp_packet_in, data);
    ds_put_format(string, " data_len=%zu", data_len);
    if (htonl(op->buffer_id) == UINT32_MAX) {
        ds_put_format(string, " (unbuffered)");
        if (ntohs(op->total_len) != data_len)
            ds_put_format(string, " (***total_len != data_len***)");
    } else {
        ds_put_format(string, " buffer=0x%08"PRIx32, ntohl(op->buffer_id));
        if (ntohs(op->total_len) < data_len)
            ds_put_format(string, " (***total_len < data_len***)");
    }
    ds_put_char(string, '\n');

    if (verbosity > 0) {
        struct flow flow;
        struct ofpbuf packet;

        ofpbuf_use_const(&packet, op->data, data_len);
        flow_extract(&packet, 0, ntohs(op->in_port), &flow);
        flow_format(string, &flow);
        ds_put_char(string, '\n');
    }
    if (verbosity > 1) {
        char *packet = ofp_packet_to_string(op->data, data_len,
                                            ntohs(op->total_len));
        ds_put_cstr(string, packet);
        free(packet);
    }
}

static void ofp_print_port_name(struct ds *string, uint16_t port)
{
    const char *name;
    switch (port) {
    case OFPP_IN_PORT:
        name = "IN_PORT";
        break;
    case OFPP_TABLE:
        name = "TABLE";
        break;
    case OFPP_NORMAL:
        name = "NORMAL";
        break;
    case OFPP_FLOOD:
        name = "FLOOD";
        break;
    case OFPP_ALL:
        name = "ALL";
        break;
    case OFPP_CONTROLLER:
        name = "CONTROLLER";
        break;
    case OFPP_LOCAL:
        name = "LOCAL";
        break;
    case OFPP_NONE:
        name = "NONE";
        break;
    default:
        ds_put_format(string, "%"PRIu16, port);
        return;
    }
    ds_put_cstr(string, name);
}

static void
print_note(struct ds *string, const struct nx_action_note *nan)
{
    size_t len;
    size_t i;

    ds_put_cstr(string, "note:");
    len = ntohs(nan->len) - offsetof(struct nx_action_note, note);
    for (i = 0; i < len; i++) {
        if (i) {
            ds_put_char(string, '.');
        }
        ds_put_format(string, "%02"PRIx8, nan->note[i]);
    }
}

static void
ofp_print_nx_action(struct ds *string, const struct nx_action_header *nah)
{
    switch (ntohs(nah->subtype)) {
    case NXAST_RESUBMIT: {
        const struct nx_action_resubmit *nar = (struct nx_action_resubmit *)nah;
        ds_put_format(string, "resubmit:");
        ofp_print_port_name(string, ntohs(nar->in_port));
        break;
    }

    case NXAST_SET_TUNNEL: {
        const struct nx_action_set_tunnel *nast =
                                            (struct nx_action_set_tunnel *)nah;
        ds_put_format(string, "set_tunnel:%#"PRIx32, ntohl(nast->tun_id));
        break;
    }

    case NXAST_DROP_SPOOFED_ARP:
        ds_put_cstr(string, "drop_spoofed_arp");
        break;

    case NXAST_SET_QUEUE: {
        const struct nx_action_set_queue *nasq =
                                            (struct nx_action_set_queue *)nah;
        ds_put_format(string, "set_queue:%u", ntohl(nasq->queue_id));
        break;
    }

    case NXAST_POP_QUEUE:
        ds_put_cstr(string, "pop_queue");
        break;

    case NXAST_NOTE:
        print_note(string, (const struct nx_action_note *) nah);
        break;

    default:
        ds_put_format(string, "***unknown Nicira action:%d***",
                      ntohs(nah->subtype));
    }
}

static int
ofp_print_action(struct ds *string, const struct ofp_action_header *ah,
        size_t actions_len)
{
    uint16_t type;
    size_t len;

    struct openflow_action {
        size_t min_size;
        size_t max_size;
    };

    const struct openflow_action of_actions[] = {
        [OFPAT_OUTPUT] = {
            sizeof(struct ofp_action_output),
            sizeof(struct ofp_action_output),
        },
        [OFPAT_SET_VLAN_VID] = {
            sizeof(struct ofp_action_vlan_vid),
            sizeof(struct ofp_action_vlan_vid),
        },
        [OFPAT_SET_VLAN_PCP] = {
            sizeof(struct ofp_action_vlan_pcp),
            sizeof(struct ofp_action_vlan_pcp),
        },
        [OFPAT_STRIP_VLAN] = {
            sizeof(struct ofp_action_header),
            sizeof(struct ofp_action_header),
        },
        [OFPAT_SET_DL_SRC] = {
            sizeof(struct ofp_action_dl_addr),
            sizeof(struct ofp_action_dl_addr),
        },
        [OFPAT_SET_DL_DST] = {
            sizeof(struct ofp_action_dl_addr),
            sizeof(struct ofp_action_dl_addr),
        },
        [OFPAT_SET_NW_SRC] = {
            sizeof(struct ofp_action_nw_addr),
            sizeof(struct ofp_action_nw_addr),
        },
        [OFPAT_SET_NW_DST] = {
            sizeof(struct ofp_action_nw_addr),
            sizeof(struct ofp_action_nw_addr),
        },
        [OFPAT_SET_NW_TOS] = {
            sizeof(struct ofp_action_nw_tos),
            sizeof(struct ofp_action_nw_tos),
        },
        [OFPAT_SET_TP_SRC] = {
            sizeof(struct ofp_action_tp_port),
            sizeof(struct ofp_action_tp_port),
        },
        [OFPAT_SET_TP_DST] = {
            sizeof(struct ofp_action_tp_port),
            sizeof(struct ofp_action_tp_port),
        },
        [OFPAT_ENQUEUE] = {
            sizeof(struct ofp_action_enqueue),
            sizeof(struct ofp_action_enqueue),
        }
        /* OFPAT_VENDOR is not here, since it would blow up the array size. */
    };

    if (actions_len < sizeof *ah) {
        ds_put_format(string, "***action array too short for next action***\n");
        return -1;
    }

    type = ntohs(ah->type);
    len = ntohs(ah->len);
    if (actions_len < len) {
        ds_put_format(string, "***truncated action %"PRIu16"***\n", type);
        return -1;
    }

    if (!len) {
        ds_put_format(string, "***zero-length action***\n");
        return 8;
    }

    if ((len % OFP_ACTION_ALIGN) != 0) {
        ds_put_format(string,
                      "***action %"PRIu16" length not a multiple of %d***\n",
                      type, OFP_ACTION_ALIGN);
        return -1;
    }

    if (type < ARRAY_SIZE(of_actions)) {
        const struct openflow_action *act = &of_actions[type];
        if ((len < act->min_size) || (len > act->max_size)) {
            ds_put_format(string,
                    "***action %"PRIu16" wrong length: %zu***\n", type, len);
            return -1;
        }
    }

    switch (type) {
    case OFPAT_OUTPUT: {
        struct ofp_action_output *oa = (struct ofp_action_output *)ah;
        uint16_t port = ntohs(oa->port);
        if (port < OFPP_MAX) {
            ds_put_format(string, "output:%"PRIu16, port);
        } else {
            ofp_print_port_name(string, port);
            if (port == OFPP_CONTROLLER) {
                if (oa->max_len) {
                    ds_put_format(string, ":%"PRIu16, ntohs(oa->max_len));
                } else {
                    ds_put_cstr(string, ":all");
                }
            }
        }
        break;
    }

    case OFPAT_ENQUEUE: {
        struct ofp_action_enqueue *ea = (struct ofp_action_enqueue *)ah;
        unsigned int port = ntohs(ea->port);
        unsigned int queue_id = ntohl(ea->queue_id);
        ds_put_format(string, "enqueue:");
        if (port != OFPP_IN_PORT) {
            ds_put_format(string, "%u", port);
        } else {
            ds_put_cstr(string, "IN_PORT");
        }
        ds_put_format(string, "q%u", queue_id);
        break;
    }

    case OFPAT_SET_VLAN_VID: {
        struct ofp_action_vlan_vid *va = (struct ofp_action_vlan_vid *)ah;
        ds_put_format(string, "mod_vlan_vid:%"PRIu16, ntohs(va->vlan_vid));
        break;
    }

    case OFPAT_SET_VLAN_PCP: {
        struct ofp_action_vlan_pcp *va = (struct ofp_action_vlan_pcp *)ah;
        ds_put_format(string, "mod_vlan_pcp:%"PRIu8, va->vlan_pcp);
        break;
    }

    case OFPAT_STRIP_VLAN:
        ds_put_cstr(string, "strip_vlan");
        break;

    case OFPAT_SET_DL_SRC: {
        struct ofp_action_dl_addr *da = (struct ofp_action_dl_addr *)ah;
        ds_put_format(string, "mod_dl_src:"ETH_ADDR_FMT,
                ETH_ADDR_ARGS(da->dl_addr));
        break;
    }

    case OFPAT_SET_DL_DST: {
        struct ofp_action_dl_addr *da = (struct ofp_action_dl_addr *)ah;
        ds_put_format(string, "mod_dl_dst:"ETH_ADDR_FMT,
                ETH_ADDR_ARGS(da->dl_addr));
        break;
    }

    case OFPAT_SET_NW_SRC: {
        struct ofp_action_nw_addr *na = (struct ofp_action_nw_addr *)ah;
        ds_put_format(string, "mod_nw_src:"IP_FMT, IP_ARGS(&na->nw_addr));
        break;
    }

    case OFPAT_SET_NW_DST: {
        struct ofp_action_nw_addr *na = (struct ofp_action_nw_addr *)ah;
        ds_put_format(string, "mod_nw_dst:"IP_FMT, IP_ARGS(&na->nw_addr));
        break;
    }

    case OFPAT_SET_NW_TOS: {
        struct ofp_action_nw_tos *nt = (struct ofp_action_nw_tos *)ah;
        ds_put_format(string, "mod_nw_tos:%d", nt->nw_tos);
        break;
    }

    case OFPAT_SET_TP_SRC: {
        struct ofp_action_tp_port *ta = (struct ofp_action_tp_port *)ah;
        ds_put_format(string, "mod_tp_src:%d", ntohs(ta->tp_port));
        break;
    }

    case OFPAT_SET_TP_DST: {
        struct ofp_action_tp_port *ta = (struct ofp_action_tp_port *)ah;
        ds_put_format(string, "mod_tp_dst:%d", ntohs(ta->tp_port));
        break;
    }

    case OFPAT_VENDOR: {
        struct ofp_action_vendor_header *avh
                = (struct ofp_action_vendor_header *)ah;
        if (len < sizeof *avh) {
            ds_put_format(string, "***ofpat_vendor truncated***\n");
            return -1;
        }
        if (avh->vendor == htonl(NX_VENDOR_ID)) {
            ofp_print_nx_action(string, (struct nx_action_header *)avh);
        } else {
            ds_put_format(string, "vendor action:0x%x", ntohl(avh->vendor));
        }
        break;
    }

    default:
        ds_put_format(string, "(decoder %"PRIu16" not implemented)", type);
        break;
    }

    return len;
}

void
ofp_print_actions(struct ds *string, const struct ofp_action_header *action,
                  size_t actions_len)
{
    uint8_t *p = (uint8_t *)action;
    int len = 0;

    ds_put_cstr(string, "actions=");
    if (!actions_len) {
        ds_put_cstr(string, "drop");
    }
    while (actions_len > 0) {
        if (len) {
            ds_put_cstr(string, ",");
        }
        len = ofp_print_action(string, (struct ofp_action_header *)p,
                actions_len);
        if (len < 0) {
            return;
        }
        p += len;
        actions_len -= len;
    }
}

static void
ofp_print_packet_out(struct ds *string, const struct ofp_packet_out *opo,
                     int verbosity)
{
    size_t len = ntohs(opo->header.length);
    size_t actions_len = ntohs(opo->actions_len);

    ds_put_cstr(string, " in_port=");
    ofp_print_port_name(string, ntohs(opo->in_port));

    ds_put_format(string, " actions_len=%zu ", actions_len);
    if (actions_len > (ntohs(opo->header.length) - sizeof *opo)) {
        ds_put_format(string, "***packet too short for action length***\n");
        return;
    }
    ofp_print_actions(string, opo->actions, actions_len);

    if (ntohl(opo->buffer_id) == UINT32_MAX) {
        int data_len = len - sizeof *opo - actions_len;
        ds_put_format(string, " data_len=%d", data_len);
        if (verbosity > 0 && len > sizeof *opo) {
            char *packet = ofp_packet_to_string(
                    (uint8_t *)opo->actions + actions_len, data_len, data_len);
            ds_put_char(string, '\n');
            ds_put_cstr(string, packet);
            free(packet);
        }
    } else {
        ds_put_format(string, " buffer=0x%08"PRIx32, ntohl(opo->buffer_id));
    }
    ds_put_char(string, '\n');
}

/* qsort comparison function. */
static int
compare_ports(const void *a_, const void *b_)
{
    const struct ofp_phy_port *a = a_;
    const struct ofp_phy_port *b = b_;
    uint16_t ap = ntohs(a->port_no);
    uint16_t bp = ntohs(b->port_no);

    return ap < bp ? -1 : ap > bp;
}

static void ofp_print_port_features(struct ds *string, uint32_t features)
{
    if (features == 0) {
        ds_put_cstr(string, "Unsupported\n");
        return;
    }
    if (features & OFPPF_10MB_HD) {
        ds_put_cstr(string, "10MB-HD ");
    }
    if (features & OFPPF_10MB_FD) {
        ds_put_cstr(string, "10MB-FD ");
    }
    if (features & OFPPF_100MB_HD) {
        ds_put_cstr(string, "100MB-HD ");
    }
    if (features & OFPPF_100MB_FD) {
        ds_put_cstr(string, "100MB-FD ");
    }
    if (features & OFPPF_1GB_HD) {
        ds_put_cstr(string, "1GB-HD ");
    }
    if (features & OFPPF_1GB_FD) {
        ds_put_cstr(string, "1GB-FD ");
    }
    if (features & OFPPF_10GB_FD) {
        ds_put_cstr(string, "10GB-FD ");
    }
    if (features & OFPPF_COPPER) {
        ds_put_cstr(string, "COPPER ");
    }
    if (features & OFPPF_FIBER) {
        ds_put_cstr(string, "FIBER ");
    }
    if (features & OFPPF_AUTONEG) {
        ds_put_cstr(string, "AUTO_NEG ");
    }
    if (features & OFPPF_PAUSE) {
        ds_put_cstr(string, "AUTO_PAUSE ");
    }
    if (features & OFPPF_PAUSE_ASYM) {
        ds_put_cstr(string, "AUTO_PAUSE_ASYM ");
    }
    ds_put_char(string, '\n');
}

static void
ofp_print_phy_port(struct ds *string, const struct ofp_phy_port *port)
{
    char name[OFP_MAX_PORT_NAME_LEN];
    int j;

    memcpy(name, port->name, sizeof name);
    for (j = 0; j < sizeof name - 1; j++) {
        if (!isprint(name[j])) {
            break;
        }
    }
    name[j] = '\0';

    ds_put_char(string, ' ');
    ofp_print_port_name(string, ntohs(port->port_no));
    ds_put_format(string, "(%s): addr:"ETH_ADDR_FMT", config: %#x, state:%#x\n",
            name, ETH_ADDR_ARGS(port->hw_addr), ntohl(port->config),
            ntohl(port->state));
    if (port->curr) {
        ds_put_format(string, "     current:    ");
        ofp_print_port_features(string, ntohl(port->curr));
    }
    if (port->advertised) {
        ds_put_format(string, "     advertised: ");
        ofp_print_port_features(string, ntohl(port->advertised));
    }
    if (port->supported) {
        ds_put_format(string, "     supported:  ");
        ofp_print_port_features(string, ntohl(port->supported));
    }
    if (port->peer) {
        ds_put_format(string, "     peer:       ");
        ofp_print_port_features(string, ntohl(port->peer));
    }
}

static void
ofp_print_switch_features(struct ds *string,
                          const struct ofp_switch_features *osf)
{
    size_t len = ntohs(osf->header.length);
    struct ofp_phy_port *port_list;
    int n_ports;
    int i;

    ds_put_format(string, " ver:0x%x, dpid:%016"PRIx64"\n",
            osf->header.version, ntohll(osf->datapath_id));
    ds_put_format(string, "n_tables:%d, n_buffers:%d\n", osf->n_tables,
            ntohl(osf->n_buffers));
    ds_put_format(string, "features: capabilities:%#x, actions:%#x\n",
           ntohl(osf->capabilities), ntohl(osf->actions));

    n_ports = (len - sizeof *osf) / sizeof *osf->ports;

    port_list = xmemdup(osf->ports, len - sizeof *osf);
    qsort(port_list, n_ports, sizeof *port_list, compare_ports);
    for (i = 0; i < n_ports; i++) {
        ofp_print_phy_port(string, &port_list[i]);
    }
    free(port_list);
}

static void
ofp_print_switch_config(struct ds *string, const struct ofp_switch_config *osc)
{
    uint16_t flags;

    flags = ntohs(osc->flags);
    if (flags) {
        ds_put_format(string, " ***unknown flags 0x%04"PRIx16"***", flags);
    }

    ds_put_format(string, " miss_send_len=%"PRIu16"\n", ntohs(osc->miss_send_len));
}

static void print_wild(struct ds *string, const char *leader, int is_wild,
            int verbosity, const char *format, ...)
            __attribute__((format(printf, 5, 6)));

static void print_wild(struct ds *string, const char *leader, int is_wild,
                       int verbosity, const char *format, ...)
{
    if (is_wild && verbosity < 2) {
        return;
    }
    ds_put_cstr(string, leader);
    if (!is_wild) {
        va_list args;

        va_start(args, format);
        ds_put_format_valist(string, format, args);
        va_end(args);
    } else {
        ds_put_char(string, '*');
    }
    ds_put_char(string, ',');
}

static void
print_ip_netmask(struct ds *string, const char *leader, uint32_t ip,
                 uint32_t wild_bits, int verbosity)
{
    if (wild_bits >= 32 && verbosity < 2) {
        return;
    }
    ds_put_cstr(string, leader);
    if (wild_bits < 32) {
        ds_put_format(string, IP_FMT, IP_ARGS(&ip));
        if (wild_bits) {
            ds_put_format(string, "/%d", 32 - wild_bits);
        }
    } else {
        ds_put_char(string, '*');
    }
    ds_put_char(string, ',');
}

void
ofp_print_match(struct ds *f, const struct ofp_match *om, int verbosity)
{
    char *s = ofp_match_to_string(om, verbosity);
    ds_put_cstr(f, s);
    free(s);
}

char *
ofp_match_to_string(const struct ofp_match *om, int verbosity)
{
    struct ds f = DS_EMPTY_INITIALIZER;
    uint32_t w = ntohl(om->wildcards);
    bool skip_type = false;
    bool skip_proto = false;

    if (!(w & OFPFW_DL_TYPE)) {
        skip_type = true;
        if (om->dl_type == htons(ETH_TYPE_IP)) {
            if (!(w & OFPFW_NW_PROTO)) {
                skip_proto = true;
                if (om->nw_proto == IP_TYPE_ICMP) {
                    ds_put_cstr(&f, "icmp,");
                } else if (om->nw_proto == IP_TYPE_TCP) {
                    ds_put_cstr(&f, "tcp,");
                } else if (om->nw_proto == IP_TYPE_UDP) {
                    ds_put_cstr(&f, "udp,");
                } else {
                    ds_put_cstr(&f, "ip,");
                    skip_proto = false;
                }
            } else {
                ds_put_cstr(&f, "ip,");
            }
        } else if (om->dl_type == htons(ETH_TYPE_ARP)) {
            ds_put_cstr(&f, "arp,");
        } else {
            skip_type = false;
        }
    }
    if (w & NXFW_TUN_ID) {
        ds_put_cstr(&f, "tun_id_wild,");
    }
    print_wild(&f, "in_port=", w & OFPFW_IN_PORT, verbosity,
               "%d", ntohs(om->in_port));
    print_wild(&f, "dl_vlan=", w & OFPFW_DL_VLAN, verbosity,
               "%d", ntohs(om->dl_vlan));
    print_wild(&f, "dl_vlan_pcp=", w & OFPFW_DL_VLAN_PCP, verbosity,
               "%d", om->dl_vlan_pcp);
    print_wild(&f, "dl_src=", w & OFPFW_DL_SRC, verbosity,
               ETH_ADDR_FMT, ETH_ADDR_ARGS(om->dl_src));
    print_wild(&f, "dl_dst=", w & OFPFW_DL_DST, verbosity,
               ETH_ADDR_FMT, ETH_ADDR_ARGS(om->dl_dst));
    if (!skip_type) {
        print_wild(&f, "dl_type=", w & OFPFW_DL_TYPE, verbosity,
                   "0x%04x", ntohs(om->dl_type));
    }
    print_ip_netmask(&f, "nw_src=", om->nw_src,
                     (w & OFPFW_NW_SRC_MASK) >> OFPFW_NW_SRC_SHIFT, verbosity);
    print_ip_netmask(&f, "nw_dst=", om->nw_dst,
                     (w & OFPFW_NW_DST_MASK) >> OFPFW_NW_DST_SHIFT, verbosity);
    if (!skip_proto) {
        if (om->dl_type == htons(ETH_TYPE_ARP)) {
            print_wild(&f, "opcode=", w & OFPFW_NW_PROTO, verbosity,
                       "%u", om->nw_proto);
        } else {
            print_wild(&f, "nw_proto=", w & OFPFW_NW_PROTO, verbosity,
                       "%u", om->nw_proto);
        }
    }
    print_wild(&f, "nw_tos=", w & OFPFW_NW_TOS, verbosity,
               "%u", om->nw_tos);
    if (om->nw_proto == IP_TYPE_ICMP) {
        print_wild(&f, "icmp_type=", w & OFPFW_ICMP_TYPE, verbosity,
                   "%d", ntohs(om->icmp_type));
        print_wild(&f, "icmp_code=", w & OFPFW_ICMP_CODE, verbosity,
                   "%d", ntohs(om->icmp_code));
    } else {
        print_wild(&f, "tp_src=", w & OFPFW_TP_SRC, verbosity,
                   "%d", ntohs(om->tp_src));
        print_wild(&f, "tp_dst=", w & OFPFW_TP_DST, verbosity,
                   "%d", ntohs(om->tp_dst));
    }
    if (ds_last(&f) == ',') {
        f.length--;
    }
    return ds_cstr(&f);
}

static void
ofp_print_flow_mod(struct ds *s, const struct ofp_header *oh,
                   enum ofputil_msg_code code, int verbosity)
{
    struct flow_mod fm;
    int error;

    error = ofputil_decode_flow_mod(&fm, oh, NXFF_OPENFLOW10);
    if (error) {
        ofp_print_error(s, error);
        return;
    }

    ds_put_char(s, ' ');
    switch (fm.command) {
    case OFPFC_ADD:
        ds_put_cstr(s, "ADD");
        break;
    case OFPFC_MODIFY:
        ds_put_cstr(s, "MOD");
        break;
    case OFPFC_MODIFY_STRICT:
        ds_put_cstr(s, "MOD_STRICT");
        break;
    case OFPFC_DELETE:
        ds_put_cstr(s, "DEL");
        break;
    case OFPFC_DELETE_STRICT:
        ds_put_cstr(s, "DEL_STRICT");
        break;
    default:
        ds_put_format(s, "cmd:%d", fm.command);
    }

    ds_put_char(s, ' ');
    if (verbosity >= 3 && code == OFPUTIL_OFPT_FLOW_MOD) {
        const struct ofp_flow_mod *ofm = (const struct ofp_flow_mod *) oh;

        ofp_print_match(s, &ofm->match, verbosity);
    } else if (verbosity >= 3 && code == OFPUTIL_NXT_FLOW_MOD) {
        const struct nx_flow_mod *nfm = (const struct nx_flow_mod *) oh;
        const void *nxm = nfm + 1;
        char *nxm_s = nx_match_to_string(nxm, ntohs(nfm->match_len));
        ds_put_cstr(s, nxm_s);
        free(nxm_s);
    } else {
        cls_rule_format(&fm.cr, s);
    }

    if (ds_last(s) != ' ') {
        ds_put_char(s, ' ');
    }
    if (fm.cookie != htonll(0)) {
        ds_put_format(s, "cookie:0x%"PRIx64" ", ntohll(fm.cookie));
    }
    if (fm.idle_timeout != OFP_FLOW_PERMANENT) {
        ds_put_format(s, "idle:%"PRIu16" ", fm.idle_timeout);
    }
    if (fm.hard_timeout != OFP_FLOW_PERMANENT) {
        ds_put_format(s, "hard:%"PRIu16" ", fm.hard_timeout);
    }
    if (fm.cr.priority != OFP_DEFAULT_PRIORITY && verbosity >= 3) {
        ds_put_format(s, "pri:%"PRIu16" ", fm.cr.priority);
    }
    if (fm.buffer_id != UINT32_MAX) {
        ds_put_format(s, "buf:0x%"PRIx32" ", fm.buffer_id);
    }
    if (fm.flags != 0) {
        ds_put_format(s, "flags:0x%"PRIx16" ", fm.flags);
    }

    ofp_print_actions(s, (const struct ofp_action_header *) fm.actions,
                      fm.n_actions * sizeof *fm.actions);
}

static void
ofp_print_duration(struct ds *string, unsigned int sec, unsigned int nsec)
{
    ds_put_format(string, "%u", sec);
    if (nsec > 0) {
        ds_put_format(string, ".%09u", nsec);
        while (string->string[string->length - 1] == '0') {
            string->length--;
        }
    }
    ds_put_char(string, 's');
}

static void
ofp_print_flow_removed(struct ds *string, const struct ofp_flow_removed *ofr,
                       int verbosity)
{
    ofp_print_match(string, &ofr->match, verbosity);
    ds_put_cstr(string, " reason=");
    switch (ofr->reason) {
    case OFPRR_IDLE_TIMEOUT:
        ds_put_cstr(string, "idle");
        break;
    case OFPRR_HARD_TIMEOUT:
        ds_put_cstr(string, "hard");
        break;
    case OFPRR_DELETE:
        ds_put_cstr(string, "delete");
        break;
    default:
        ds_put_format(string, "**%"PRIu8"**", ofr->reason);
        break;
    }

    if (ofr->cookie != htonll(0)) {
        ds_put_format(string, " cookie:0x%"PRIx64, ntohll(ofr->cookie));
    }
    if (ofr->priority != htons(32768)) {
        ds_put_format(string, " pri:%"PRIu16, ntohs(ofr->priority));
    }
    ds_put_cstr(string, " duration");
    ofp_print_duration(string,
                       ntohl(ofr->duration_sec), ntohl(ofr->duration_nsec));
    ds_put_format(string, " idle%"PRIu16" pkts%"PRIu64" bytes%"PRIu64"\n",
         ntohs(ofr->idle_timeout), ntohll(ofr->packet_count),
         ntohll(ofr->byte_count));
}

static void
ofp_print_port_mod(struct ds *string, const struct ofp_port_mod *opm)
{
    ds_put_format(string, "port: %d: addr:"ETH_ADDR_FMT", config: %#x, mask:%#x\n",
            ntohs(opm->port_no), ETH_ADDR_ARGS(opm->hw_addr),
            ntohl(opm->config), ntohl(opm->mask));
    ds_put_format(string, "     advertise: ");
    if (opm->advertise) {
        ofp_print_port_features(string, ntohl(opm->advertise));
    } else {
        ds_put_format(string, "UNCHANGED\n");
    }
}

struct error_type {
    int type;
    int code;
    const char *name;
};

static const struct error_type error_types[] = {
#define ERROR_TYPE(TYPE) {TYPE, -1, #TYPE}
#define ERROR_CODE(TYPE, CODE) {TYPE, CODE, #CODE}
    ERROR_TYPE(OFPET_HELLO_FAILED),
    ERROR_CODE(OFPET_HELLO_FAILED, OFPHFC_INCOMPATIBLE),
    ERROR_CODE(OFPET_HELLO_FAILED, OFPHFC_EPERM),

    ERROR_TYPE(OFPET_BAD_REQUEST),
    ERROR_CODE(OFPET_BAD_REQUEST, OFPBRC_BAD_VERSION),
    ERROR_CODE(OFPET_BAD_REQUEST, OFPBRC_BAD_TYPE),
    ERROR_CODE(OFPET_BAD_REQUEST, OFPBRC_BAD_STAT),
    ERROR_CODE(OFPET_BAD_REQUEST, OFPBRC_BAD_VENDOR),
    ERROR_CODE(OFPET_BAD_REQUEST, OFPBRC_BAD_SUBTYPE),
    ERROR_CODE(OFPET_BAD_REQUEST, OFPBRC_EPERM),
    ERROR_CODE(OFPET_BAD_REQUEST, OFPBRC_BAD_LEN),
    ERROR_CODE(OFPET_BAD_REQUEST, OFPBRC_BUFFER_EMPTY),
    ERROR_CODE(OFPET_BAD_REQUEST, OFPBRC_BUFFER_UNKNOWN),
    /* Nicira error extensions. */
    ERROR_CODE(OFPET_BAD_REQUEST, NXBRC_NXM_INVALID),
    ERROR_CODE(OFPET_BAD_REQUEST, NXBRC_NXM_BAD_TYPE),
    ERROR_CODE(OFPET_BAD_REQUEST, NXBRC_NXM_BAD_VALUE),
    ERROR_CODE(OFPET_BAD_REQUEST, NXBRC_NXM_BAD_MASK),
    ERROR_CODE(OFPET_BAD_REQUEST, NXBRC_NXM_BAD_PREREQ),
    ERROR_CODE(OFPET_BAD_REQUEST, NXBRC_NXM_DUP_TYPE),

    ERROR_TYPE(OFPET_BAD_ACTION),
    ERROR_CODE(OFPET_BAD_ACTION, OFPBAC_BAD_TYPE),
    ERROR_CODE(OFPET_BAD_ACTION, OFPBAC_BAD_LEN),
    ERROR_CODE(OFPET_BAD_ACTION, OFPBAC_BAD_VENDOR),
    ERROR_CODE(OFPET_BAD_ACTION, OFPBAC_BAD_VENDOR_TYPE),
    ERROR_CODE(OFPET_BAD_ACTION, OFPBAC_BAD_OUT_PORT),
    ERROR_CODE(OFPET_BAD_ACTION, OFPBAC_BAD_ARGUMENT),
    ERROR_CODE(OFPET_BAD_ACTION, OFPBAC_EPERM),
    ERROR_CODE(OFPET_BAD_ACTION, OFPBAC_TOO_MANY),

    ERROR_TYPE(OFPET_FLOW_MOD_FAILED),
    ERROR_CODE(OFPET_FLOW_MOD_FAILED, OFPFMFC_ALL_TABLES_FULL),
    ERROR_CODE(OFPET_FLOW_MOD_FAILED, OFPFMFC_OVERLAP),
    ERROR_CODE(OFPET_FLOW_MOD_FAILED, OFPFMFC_EPERM),
    ERROR_CODE(OFPET_FLOW_MOD_FAILED, OFPFMFC_BAD_EMERG_TIMEOUT),
    ERROR_CODE(OFPET_FLOW_MOD_FAILED, OFPFMFC_BAD_COMMAND),
    /* Nicira error extenstions. */
    ERROR_CODE(OFPET_FLOW_MOD_FAILED, NXFMFC_HARDWARE),
    ERROR_CODE(OFPET_FLOW_MOD_FAILED, NXFMFC_BAD_TABLE_ID),

    ERROR_TYPE(OFPET_PORT_MOD_FAILED),
    ERROR_CODE(OFPET_PORT_MOD_FAILED, OFPPMFC_BAD_PORT),
    ERROR_CODE(OFPET_PORT_MOD_FAILED, OFPPMFC_BAD_HW_ADDR)
};
#define N_ERROR_TYPES ARRAY_SIZE(error_types)

static const char *
lookup_error_type(int type)
{
    const struct error_type *t;

    for (t = error_types; t < &error_types[N_ERROR_TYPES]; t++) {
        if (t->type == type && t->code == -1) {
            return t->name;
        }
    }
    return "?";
}

static const char *
lookup_error_code(int type, int code)
{
    const struct error_type *t;

    for (t = error_types; t < &error_types[N_ERROR_TYPES]; t++) {
        if (t->type == type && t->code == code) {
            return t->name;
        }
    }
    return "?";
}

static void
ofp_print_error(struct ds *string, int error)
{
    int type = get_ofp_err_type(error);
    int code = get_ofp_err_code(error);
    if (string->length) {
        ds_put_char(string, ' ');
    }
    ds_put_format(string, " ***decode error type:%d(%s) code:%d(%s)***",
                  type, lookup_error_type(type),
                  code, lookup_error_code(type, code));
}

static void
ofp_print_nx_error_msg(struct ds *string, const struct ofp_error_msg *oem)
{
    size_t len = ntohs(oem->header.length);
    const struct nx_vendor_error *nve = (struct nx_vendor_error *)oem->data;
    int vendor = ntohl(nve->vendor);
    int type = ntohs(nve->type);
    int code = ntohs(nve->code);

    ds_put_format(string, " vendor:%x type:%d(%s) code:%d(%s) payload:\n",
                  vendor,
                  type, lookup_error_type(type),
                  code, lookup_error_code(type, code));

    ds_put_hex_dump(string, nve + 1, len - sizeof *oem - sizeof *nve,
                    0, true);
}

static void
ofp_print_error_msg(struct ds *string, const struct ofp_error_msg *oem)
{
    size_t len = ntohs(oem->header.length);
    int type = ntohs(oem->type);
    int code = ntohs(oem->code);
    char *s;


    if (type == NXET_VENDOR && code == NXVC_VENDOR_ERROR) {
        if (len < sizeof *oem + sizeof(struct nx_vendor_error)) {
            ds_put_format(string,
                          "(***truncated extended error message is %zu bytes "
                          "when it should be at least %zu***)\n",
                          len, sizeof(struct nx_vendor_error));
            return;
        }

        return ofp_print_nx_error_msg(string, oem);
    }

    ds_put_format(string, " type:%d(%s) code:%d(%s) payload:\n",
                  type, lookup_error_type(type),
                  code, lookup_error_code(type, code));

    switch (type) {
    case OFPET_HELLO_FAILED:
        ds_put_printable(string, (char *) oem->data, len - sizeof *oem);
        break;

    case OFPET_BAD_REQUEST:
        s = ofp_to_string(oem->data, len - sizeof *oem, 1);
        ds_put_cstr(string, s);
        free(s);
        break;

    default:
        ds_put_hex_dump(string, oem->data, len - sizeof *oem, 0, true);
        break;
    }
}

static void
ofp_print_port_status(struct ds *string, const struct ofp_port_status *ops)
{
    if (ops->reason == OFPPR_ADD) {
        ds_put_format(string, " ADD:");
    } else if (ops->reason == OFPPR_DELETE) {
        ds_put_format(string, " DEL:");
    } else if (ops->reason == OFPPR_MODIFY) {
        ds_put_format(string, " MOD:");
    }

    ofp_print_phy_port(string, &ops->desc);
}

static void
ofp_print_ofpst_desc_reply(struct ds *string, const struct ofp_header *oh)
{
    const struct ofp_desc_stats *ods = ofputil_stats_body(oh);

    ds_put_format(string, "Manufacturer: %.*s\n",
            (int) sizeof ods->mfr_desc, ods->mfr_desc);
    ds_put_format(string, "Hardware: %.*s\n",
            (int) sizeof ods->hw_desc, ods->hw_desc);
    ds_put_format(string, "Software: %.*s\n",
            (int) sizeof ods->sw_desc, ods->sw_desc);
    ds_put_format(string, "Serial Num: %.*s\n",
            (int) sizeof ods->serial_num, ods->serial_num);
    ds_put_format(string, "DP Description: %.*s\n",
            (int) sizeof ods->dp_desc, ods->dp_desc);
}

static void
ofp_print_flow_stats_request(struct ds *string, const struct ofp_header *oh)
{
    struct flow_stats_request fsr;
    int error;

    error = ofputil_decode_flow_stats_request(&fsr, oh, NXFF_OPENFLOW10);
    if (error) {
        ofp_print_error(string, error);
        return;
    }

    if (fsr.table_id != 0xff) {
        ds_put_format(string, " table_id=%"PRIu8, fsr.table_id);
    }

    if (fsr.out_port != OFPP_NONE) {
        ds_put_cstr(string, " out_port=");
        ofp_print_port_name(string, fsr.out_port);
    }

    ds_put_char(string, ' ');
    cls_rule_format(&fsr.match, string);
}

static void
ofp_print_ofpst_flow_reply(struct ds *string, const struct ofp_header *oh,
                           int verbosity)
{
    size_t len = ofputil_stats_body_len(oh);
    const char *body = ofputil_stats_body(oh);
    const char *pos = body;
    for (;;) {
        const struct ofp_flow_stats *fs;
        ptrdiff_t bytes_left = body + len - pos;
        size_t length;

        ds_put_char(string, '\n');

        if (bytes_left < sizeof *fs) {
            if (bytes_left != 0) {
                ds_put_format(string, " ***%td leftover bytes at end***",
                              bytes_left);
            }
            break;
        }

        fs = (const void *) pos;
        length = ntohs(fs->length);
        if (length < sizeof *fs) {
            ds_put_format(string, " ***length=%zu shorter than minimum %zu***",
                          length, sizeof *fs);
            break;
        } else if (length > bytes_left) {
            ds_put_format(string,
                          " ***length=%zu but only %td bytes left***",
                          length, bytes_left);
            break;
        } else if ((length - sizeof *fs) % sizeof fs->actions[0]) {
            ds_put_format(string,
                          " ***length=%zu has %zu bytes leftover in "
                          "final action***",
                          length,
                          (length - sizeof *fs) % sizeof fs->actions[0]);
            break;
        }

        ds_put_format(string, " cookie=0x%"PRIx64", duration=",
                      ntohll(fs->cookie));
        ofp_print_duration(string, ntohl(fs->duration_sec),
                           ntohl(fs->duration_nsec));
        ds_put_format(string, ", table_id=%"PRIu8", ", fs->table_id);
        ds_put_format(string, "priority=%"PRIu16", ", ntohs(fs->priority));
        ds_put_format(string, "n_packets=%"PRIu64", ",
                    ntohll(fs->packet_count));
        ds_put_format(string, "n_bytes=%"PRIu64", ", ntohll(fs->byte_count));
        if (fs->idle_timeout != htons(OFP_FLOW_PERMANENT)) {
            ds_put_format(string, "idle_timeout=%"PRIu16",",
                          ntohs(fs->idle_timeout));
        }
        if (fs->hard_timeout != htons(OFP_FLOW_PERMANENT)) {
            ds_put_format(string, "hard_timeout=%"PRIu16",",
                          ntohs(fs->hard_timeout));
        }
        ofp_print_match(string, &fs->match, verbosity);
        ds_put_char(string, ' ');
        ofp_print_actions(string, fs->actions, length - sizeof *fs);

        pos += length;
     }
}

static void
ofp_print_nxst_flow_reply(struct ds *string, const struct ofp_header *oh)
{
    struct ofpbuf b;

    ofpbuf_use_const(&b, ofputil_nxstats_body(oh),
                     ofputil_nxstats_body_len(oh));
    while (b.size > 0) {
        const struct nx_flow_stats *fs;
        union ofp_action *actions;
        struct cls_rule rule;
        size_t actions_len, n_actions;
        size_t length;
        int match_len;
        int error;

        fs = ofpbuf_try_pull(&b, sizeof *fs);
        if (!fs) {
            ds_put_format(string, " ***%td leftover bytes at end***", b.size);
            break;
        }

        length = ntohs(fs->length);
        if (length < sizeof *fs) {
            ds_put_format(string, " ***nx_flow_stats claims length %zu***",
                          length);
            break;
        }

        match_len = ntohs(fs->match_len);
        if (match_len > length - sizeof *fs) {
            ds_put_format(string, " ***length=%zu match_len=%d***",
                          length, match_len);
            break;
        }

        ds_put_format(string, " cookie=0x%"PRIx64", duration=",
                      ntohll(fs->cookie));
        ofp_print_duration(string, ntohl(fs->duration_sec),
                           ntohl(fs->duration_nsec));
        ds_put_format(string, ", table_id=%"PRIu8", ", fs->table_id);
        ds_put_format(string, "priority=%"PRIu16", ", ntohs(fs->priority));
        ds_put_format(string, "n_packets=%"PRIu64", ",
                    ntohll(fs->packet_count));
        ds_put_format(string, "n_bytes=%"PRIu64", ", ntohll(fs->byte_count));
        if (fs->idle_timeout != htons(OFP_FLOW_PERMANENT)) {
            ds_put_format(string, "idle_timeout=%"PRIu16",",
                          ntohs(fs->idle_timeout));
        }
        if (fs->hard_timeout != htons(OFP_FLOW_PERMANENT)) {
            ds_put_format(string, "hard_timeout=%"PRIu16",",
                          ntohs(fs->hard_timeout));
        }

        error = nx_pull_match(&b, match_len, ntohs(fs->priority), &rule);
        if (error) {
            ofp_print_error(string, error);
            break;
        }

        actions_len = length - sizeof *fs - ROUND_UP(match_len, 8);
        error = ofputil_pull_actions(&b, actions_len, &actions, &n_actions);
        if (error) {
            ofp_print_error(string, error);
            break;
        }

        cls_rule_format(&rule, string);
        ds_put_char(string, ' ');
        ofp_print_actions(string, (const struct ofp_action_header *) actions,
                          n_actions * sizeof *actions);
        ds_put_char(string, '\n');
     }
}

static void
ofp_print_ofpst_aggregate_reply(struct ds *string, const struct ofp_header *oh)
{
    const struct ofp_aggregate_stats_reply *asr = ofputil_stats_body(oh);

    ds_put_format(string, " packet_count=%"PRIu64, ntohll(asr->packet_count));
    ds_put_format(string, " byte_count=%"PRIu64, ntohll(asr->byte_count));
    ds_put_format(string, " flow_count=%"PRIu32, ntohl(asr->flow_count));
}

static void print_port_stat(struct ds *string, const char *leader,
                            uint64_t stat, int more)
{
    ds_put_cstr(string, leader);
    if (stat != -1) {
        ds_put_format(string, "%"PRIu64, stat);
    } else {
        ds_put_char(string, '?');
    }
    if (more) {
        ds_put_cstr(string, ", ");
    } else {
        ds_put_cstr(string, "\n");
    }
}

static void
ofp_print_ofpst_port_request(struct ds *string, const struct ofp_header *oh)
{
    const struct ofp_port_stats_request *psr = ofputil_stats_body(oh);
    ds_put_format(string, "port_no=%"PRIu16, ntohs(psr->port_no));
}

static void
ofp_print_ofpst_port_reply(struct ds *string, const struct ofp_header *oh,
                           int verbosity)
{
    const struct ofp_port_stats *ps = ofputil_stats_body(oh);
    size_t n = ofputil_stats_body_len(oh) / sizeof *ps;
    ds_put_format(string, " %zu ports\n", n);
    if (verbosity < 1) {
        return;
    }

    for (; n--; ps++) {
        ds_put_format(string, "  port %2"PRIu16": ", ntohs(ps->port_no));

        ds_put_cstr(string, "rx ");
        print_port_stat(string, "pkts=", ntohll(ps->rx_packets), 1);
        print_port_stat(string, "bytes=", ntohll(ps->rx_bytes), 1);
        print_port_stat(string, "drop=", ntohll(ps->rx_dropped), 1);
        print_port_stat(string, "errs=", ntohll(ps->rx_errors), 1);
        print_port_stat(string, "frame=", ntohll(ps->rx_frame_err), 1);
        print_port_stat(string, "over=", ntohll(ps->rx_over_err), 1);
        print_port_stat(string, "crc=", ntohll(ps->rx_crc_err), 0);

        ds_put_cstr(string, "           tx ");
        print_port_stat(string, "pkts=", ntohll(ps->tx_packets), 1);
        print_port_stat(string, "bytes=", ntohll(ps->tx_bytes), 1);
        print_port_stat(string, "drop=", ntohll(ps->tx_dropped), 1);
        print_port_stat(string, "errs=", ntohll(ps->tx_errors), 1);
        print_port_stat(string, "coll=", ntohll(ps->collisions), 0);
    }
}

static void
ofp_print_ofpst_table_reply(struct ds *string, const struct ofp_header *oh,
                            int verbosity)
{
    const struct ofp_table_stats *ts = ofputil_stats_body(oh);
    size_t n = ofputil_stats_body_len(oh) / sizeof *ts;
    ds_put_format(string, " %zu tables\n", n);
    if (verbosity < 1) {
        return;
    }

    for (; n--; ts++) {
        char name[OFP_MAX_TABLE_NAME_LEN + 1];
        strncpy(name, ts->name, sizeof name);
        name[OFP_MAX_TABLE_NAME_LEN] = '\0';

        ds_put_format(string, "  %d: %-8s: ", ts->table_id, name);
        ds_put_format(string, "wild=0x%05"PRIx32", ", ntohl(ts->wildcards));
        ds_put_format(string, "max=%6"PRIu32", ", ntohl(ts->max_entries));
        ds_put_format(string, "active=%"PRIu32"\n", ntohl(ts->active_count));
        ds_put_cstr(string, "               ");
        ds_put_format(string, "lookup=%"PRIu64", ",
                    ntohll(ts->lookup_count));
        ds_put_format(string, "matched=%"PRIu64"\n",
                    ntohll(ts->matched_count));
     }
}

static void
ofp_print_queue_name(struct ds *string, uint32_t queue_id)
{
    if (queue_id == OFPQ_ALL) {
        ds_put_cstr(string, "ALL");
    } else {
        ds_put_format(string, "%"PRIu32, queue_id);
    }
}

static void
ofp_print_ofpst_queue_request(struct ds *string, const struct ofp_header *oh)
{
    const struct ofp_queue_stats_request *qsr = ofputil_stats_body(oh);

    ds_put_cstr(string, "port=");
    ofp_print_port_name(string, ntohs(qsr->port_no));

    ds_put_cstr(string, " queue=");
    ofp_print_queue_name(string, ntohl(qsr->queue_id));
}

static void
ofp_print_ofpst_queue_reply(struct ds *string, const struct ofp_header *oh,
                            int verbosity)
{
    const struct ofp_queue_stats *qs = ofputil_stats_body(oh);
    size_t n = ofputil_stats_body_len(oh) / sizeof *qs;
    ds_put_format(string, " %zu queues\n", n);
    if (verbosity < 1) {
        return;
    }

    for (; n--; qs++) {
        ds_put_cstr(string, "  port ");
        ofp_print_port_name(string, ntohs(qs->port_no));
        ds_put_cstr(string, " queue ");
        ofp_print_queue_name(string, ntohl(qs->queue_id));
        ds_put_cstr(string, ": ");

        print_port_stat(string, "bytes=", ntohll(qs->tx_bytes), 1);
        print_port_stat(string, "pkts=", ntohll(qs->tx_packets), 1);
        print_port_stat(string, "errors=", ntohll(qs->tx_errors), 0);
    }
}

static void
ofp_print_stats_request(struct ds *string, const struct ofp_header *oh)
{
    const struct ofp_stats_request *srq
        = (const struct ofp_stats_request *) oh;

    if (srq->flags) {
        ds_put_format(string, " ***unknown flags 0x%04"PRIx16"***",
                      ntohs(srq->flags));
    }
}

static void
ofp_print_stats_reply(struct ds *string, const struct ofp_header *oh)
{
    const struct ofp_stats_reply *srp = (const struct ofp_stats_reply *) oh;

    if (srp->flags) {
        uint16_t flags = ntohs(srp->flags);

        ds_put_cstr(string, " flags=");
        if (flags & OFPSF_REPLY_MORE) {
            ds_put_cstr(string, "[more]");
            flags &= ~OFPSF_REPLY_MORE;
        }
        if (flags) {
            ds_put_format(string, "[***unknown flags 0x%04"PRIx16"***]",
                          flags);
        }
    }
}

static void
ofp_print_echo(struct ds *string, const struct ofp_header *oh, int verbosity)
{
    size_t len = ntohs(oh->length);

    ds_put_format(string, " %zu bytes of payload\n", len - sizeof *oh);
    if (verbosity > 1) {
        ds_put_hex_dump(string, oh + 1, len - sizeof *oh, 0, true);
    }
}

static void
ofp_print_nxt_status_message(struct ds *string, const struct ofp_header *oh)
{
    struct ofpbuf b;

    ofpbuf_use_const(&b, oh, ntohs(oh->length));
    ofpbuf_pull(&b, sizeof *oh);
    ds_put_char(string, '"');
    ds_put_printable(string, b.data, b.size);
    ds_put_char(string, '"');
}

static void
ofp_print_nxt_tun_id_from_cookie(struct ds *string,
                                 const struct nxt_tun_id_cookie *ntic)
{
    ds_put_format(string, " set=%"PRIu8, ntic->set);
}

static void
ofp_print_nxt_role_message(struct ds *string,
                           const struct nx_role_request *nrr)
{
    unsigned int role = ntohl(nrr->role);

    ds_put_cstr(string, " role=");
    if (role == NX_ROLE_OTHER) {
        ds_put_cstr(string, "other");
    } else if (role == NX_ROLE_MASTER) {
        ds_put_cstr(string, "master");
    } else if (role == NX_ROLE_SLAVE) {
        ds_put_cstr(string, "slave");
    } else {
        ds_put_format(string, "%u", role);
    }
}

static void
ofp_print_nxt_set_flow_format(struct ds *string,
                              const struct nxt_set_flow_format *nsff)
{
    uint32_t format = ntohl(nsff->format);

    ds_put_cstr(string, " format=");
    if (ofputil_flow_format_is_valid(format)) {
        ds_put_cstr(string, ofputil_flow_format_to_string(format));
    } else {
        ds_put_format(string, "%"PRIu32, format);
    }
}

static void
ofp_to_string__(const struct ofp_header *oh,
                const struct ofputil_msg_type *type, struct ds *string,
                int verbosity)
{
    enum ofputil_msg_code code;
    const void *msg = oh;

    ds_put_format(string, "%s (xid=0x%"PRIx32"):",
                  ofputil_msg_type_name(type), ntohl(oh->xid));

    code = ofputil_msg_type_code(type);
    switch (code) {
    case OFPUTIL_INVALID:
        break;

    case OFPUTIL_OFPT_HELLO:
        break;

    case OFPUTIL_OFPT_ERROR:
        ofp_print_error_msg(string, msg);
        break;

    case OFPUTIL_OFPT_ECHO_REQUEST:
    case OFPUTIL_OFPT_ECHO_REPLY:
        ofp_print_echo(string, oh, verbosity);
        break;

    case OFPUTIL_OFPT_FEATURES_REQUEST:
        break;

    case OFPUTIL_OFPT_FEATURES_REPLY:
        ofp_print_switch_features(string, msg);
        break;

    case OFPUTIL_OFPT_GET_CONFIG_REQUEST:
        break;

    case OFPUTIL_OFPT_GET_CONFIG_REPLY:
    case OFPUTIL_OFPT_SET_CONFIG:
        ofp_print_switch_config(string, msg);
        break;

    case OFPUTIL_OFPT_PACKET_IN:
        ofp_print_packet_in(string, msg, verbosity);
        break;

    case OFPUTIL_OFPT_FLOW_REMOVED:
        ofp_print_flow_removed(string, msg, verbosity);
        break;

    case OFPUTIL_OFPT_PORT_STATUS:
        ofp_print_port_status(string, msg);
        break;

    case OFPUTIL_OFPT_PACKET_OUT:
        ofp_print_packet_out(string, msg, verbosity);
        break;

    case OFPUTIL_OFPT_FLOW_MOD:
        ofp_print_flow_mod(string, msg, code, verbosity);
        break;

    case OFPUTIL_OFPT_PORT_MOD:
        ofp_print_port_mod(string, msg);
        break;

    case OFPUTIL_OFPT_BARRIER_REQUEST:
    case OFPUTIL_OFPT_BARRIER_REPLY:
        break;

    case OFPUTIL_OFPT_QUEUE_GET_CONFIG_REQUEST:
    case OFPUTIL_OFPT_QUEUE_GET_CONFIG_REPLY:
        /* XXX */
        break;

    case OFPUTIL_OFPST_DESC_REQUEST:
        ofp_print_stats_request(string, oh);
        break;

    case OFPUTIL_OFPST_FLOW_REQUEST:
    case OFPUTIL_NXST_FLOW_REQUEST:
    case OFPUTIL_OFPST_AGGREGATE_REQUEST:
    case OFPUTIL_NXST_AGGREGATE_REQUEST:
        ofp_print_stats_request(string, oh);
        ofp_print_flow_stats_request(string, oh);
        break;

    case OFPUTIL_OFPST_TABLE_REQUEST:
        ofp_print_stats_request(string, oh);
        break;

    case OFPUTIL_OFPST_PORT_REQUEST:
        ofp_print_stats_request(string, oh);
        ofp_print_ofpst_port_request(string, oh);
        break;

    case OFPUTIL_OFPST_QUEUE_REQUEST:
        ofp_print_stats_request(string, oh);
        ofp_print_ofpst_queue_request(string, oh);
        break;

    case OFPUTIL_OFPST_DESC_REPLY:
        ofp_print_stats_reply(string, oh);
        ofp_print_ofpst_desc_reply(string, oh);
        break;

    case OFPUTIL_OFPST_FLOW_REPLY:
        ofp_print_stats_reply(string, oh);
        ofp_print_ofpst_flow_reply(string, oh, verbosity);
        break;

    case OFPUTIL_OFPST_QUEUE_REPLY:
        ofp_print_stats_reply(string, oh);
        ofp_print_ofpst_queue_reply(string, oh, verbosity);
        break;

    case OFPUTIL_OFPST_PORT_REPLY:
        ofp_print_stats_reply(string, oh);
        ofp_print_ofpst_port_reply(string, oh, verbosity);
        break;

    case OFPUTIL_OFPST_TABLE_REPLY:
        ofp_print_stats_reply(string, oh);
        ofp_print_ofpst_table_reply(string, oh, verbosity);
        break;

    case OFPUTIL_OFPST_AGGREGATE_REPLY:
        ofp_print_stats_reply(string, oh);
        ofp_print_ofpst_aggregate_reply(string, oh);
        break;

    case OFPUTIL_NXT_STATUS_REQUEST:
    case OFPUTIL_NXT_STATUS_REPLY:
        ofp_print_nxt_status_message(string, oh);
        break;

    case OFPUTIL_NXT_TUN_ID_FROM_COOKIE:
        ofp_print_nxt_tun_id_from_cookie(string, msg);
        break;

    case OFPUTIL_NXT_ROLE_REQUEST:
    case OFPUTIL_NXT_ROLE_REPLY:
        ofp_print_nxt_role_message(string, msg);
        break;

    case OFPUTIL_NXT_SET_FLOW_FORMAT:
        ofp_print_nxt_set_flow_format(string, msg);
        break;

    case OFPUTIL_NXT_FLOW_MOD:
        ofp_print_flow_mod(string, msg, code, verbosity);
        break;

    case OFPUTIL_NXT_FLOW_REMOVED:
        /* XXX */
        break;

    case OFPUTIL_NXST_FLOW_REPLY:
        ofp_print_nxst_flow_reply(string, oh);
        break;

    case OFPUTIL_NXST_AGGREGATE_REPLY:
        /* XXX */
        break;
    }
}

/* Composes and returns a string representing the OpenFlow packet of 'len'
 * bytes at 'oh' at the given 'verbosity' level.  0 is a minimal amount of
 * verbosity and higher numbers increase verbosity.  The caller is responsible
 * for freeing the string. */
char *
ofp_to_string(const void *oh_, size_t len, int verbosity)
{
    struct ds string = DS_EMPTY_INITIALIZER;
    const struct ofp_header *oh = oh_;

    if (len < sizeof(struct ofp_header)) {
        ds_put_cstr(&string, "OpenFlow packet too short:\n");
    } else if (oh->version != OFP_VERSION) {
        ds_put_format(&string, "Bad OpenFlow version %"PRIu8":\n",
                      oh->version);
    } else if (ntohs(oh->length) > len) {
        ds_put_format(&string,
                      "(***truncated to %zu bytes from %"PRIu16"***)",
                      len, ntohs(oh->length));
    } else if (ntohs(oh->length) < len) {
        ds_put_format(&string,
                      "(***only uses %"PRIu16" bytes out of %zu***)\n",
                      ntohs(oh->length), len);
    } else {
        const struct ofputil_msg_type *type;
        int error;

        error = ofputil_decode_msg_type(oh, &type);
        if (!error) {
            ofp_to_string__(oh, type, &string, verbosity);
            if (verbosity >= 5) {
                if (ds_last(&string) != '\n') {
                    ds_put_char(&string, '\n');
                }
                ds_put_hex_dump(&string, oh, len, 0, true);
            }
            if (ds_last(&string) != '\n') {
                ds_put_char(&string, '\n');
            }
            return ds_steal_cstr(&string);
        }

        ofp_print_error(&string, error);
    }
    ds_put_hex_dump(&string, oh, len, 0, true);
    return ds_steal_cstr(&string);
}

/* Returns the name for the specified OpenFlow message type as a string,
 * e.g. "OFPT_FEATURES_REPLY".  If no name is known, the string returned is a
 * hex number, e.g. "0x55".
 *
 * The caller must free the returned string when it is no longer needed. */
char *
ofp_message_type_to_string(uint8_t type)
{
    const char *name;

    switch (type) {
    case OFPT_HELLO:
        name = "HELLO";
        break;
    case OFPT_ERROR:
        name = "ERROR";
        break;
    case OFPT_ECHO_REQUEST:
        name = "ECHO_REQUEST";
        break;
    case OFPT_ECHO_REPLY:
        name = "ECHO_REPLY";
        break;
    case OFPT_VENDOR:
        name = "VENDOR";
        break;
    case OFPT_FEATURES_REQUEST:
        name = "FEATURES_REQUEST";
        break;
    case OFPT_FEATURES_REPLY:
        name = "FEATURES_REPLY";
        break;
    case OFPT_GET_CONFIG_REQUEST:
        name = "GET_CONFIG_REQUEST";
        break;
    case OFPT_GET_CONFIG_REPLY:
        name = "GET_CONFIG_REPLY";
        break;
    case OFPT_SET_CONFIG:
        name = "SET_CONFIG";
        break;
    case OFPT_PACKET_IN:
        name = "PACKET_IN";
        break;
    case OFPT_FLOW_REMOVED:
        name = "FLOW_REMOVED";
        break;
    case OFPT_PORT_STATUS:
        name = "PORT_STATUS";
        break;
    case OFPT_PACKET_OUT:
        name = "PACKET_OUT";
        break;
    case OFPT_FLOW_MOD:
        name = "FLOW_MOD";
        break;
    case OFPT_PORT_MOD:
        name = "PORT_MOD";
        break;
    case OFPT_STATS_REQUEST:
        name = "STATS_REQUEST";
        break;
    case OFPT_STATS_REPLY:
        name = "STATS_REPLY";
        break;
    case OFPT_BARRIER_REQUEST:
        name = "BARRIER_REQUEST";
        break;
    case OFPT_BARRIER_REPLY:
        name = "BARRIER_REPLY";
        break;
    case OFPT_QUEUE_GET_CONFIG_REQUEST:
        name = "QUEUE_GET_CONFIG_REQUEST";
        break;
    case OFPT_QUEUE_GET_CONFIG_REPLY:
        name = "QUEUE_GET_CONFIG_REPLY";
        break;
    default:
        name = NULL;
        break;
    }

    return name ? xasprintf("OFPT_%s", name) : xasprintf("0x%02"PRIx8, type);
}
\f
static void
print_and_free(FILE *stream, char *string)
{
    fputs(string, stream);
    free(string);
}

/* Pretty-print the OpenFlow packet of 'len' bytes at 'oh' to 'stream' at the
 * given 'verbosity' level.  0 is a minimal amount of verbosity and higher
 * numbers increase verbosity. */
void
ofp_print(FILE *stream, const void *oh, size_t len, int verbosity)
{
    print_and_free(stream, ofp_to_string(oh, len, verbosity));
}

/* Dumps the contents of the Ethernet frame in the 'len' bytes starting at
 * 'data' to 'stream' using tcpdump.  'total_len' specifies the full length of
 * the Ethernet frame (of which 'len' bytes were captured).
 *
 * This starts and kills a tcpdump subprocess so it's quite expensive. */
void
ofp_print_packet(FILE *stream, const void *data, size_t len, size_t total_len)
{
    print_and_free(stream, ofp_packet_to_string(data, len, total_len));
}