Example #1
0
static enum ofperr
process_switch_features(struct lswitch *sw, struct ofp_header *oh)
{
    struct ofputil_switch_features features;

    struct ofpbuf b = ofpbuf_const_initializer(oh, ntohs(oh->length));
    enum ofperr error = ofputil_pull_switch_features(&b, &features);
    if (error) {
        VLOG_ERR("received invalid switch feature reply (%s)",
                 ofperr_to_string(error));
        return error;
    }

    sw->datapath_id = features.datapath_id;

    return 0;
}
Example #2
0
static enum ofperr
nx_pull_raw(const uint8_t *p, unsigned int match_len, bool strict,
            struct match *match, ovs_be64 *cookie, ovs_be64 *cookie_mask)
{
    uint32_t header;

    ovs_assert((cookie != NULL) == (cookie_mask != NULL));

    match_init_catchall(match);
    if (cookie) {
        *cookie = *cookie_mask = htonll(0);
    }
    if (!match_len) {
        return 0;
    }

    for (;
         (header = nx_entry_ok(p, match_len)) != 0;
         p += 4 + NXM_LENGTH(header), match_len -= 4 + NXM_LENGTH(header)) {
        const struct mf_field *mf;
        enum ofperr error;

        mf = mf_from_nxm_header(header);
        if (!mf) {
            if (strict) {
                error = OFPERR_OFPBMC_BAD_FIELD;
            } else {
                continue;
            }
        } else if (!mf_are_prereqs_ok(mf, &match->flow)) {
            error = OFPERR_OFPBMC_BAD_PREREQ;
        } else if (!mf_is_all_wild(mf, &match->wc)) {
            error = OFPERR_OFPBMC_DUP_FIELD;
        } else {
            unsigned int width = mf->n_bytes;
            union mf_value value;

            memcpy(&value, p + 4, width);
            if (!mf_is_value_valid(mf, &value)) {
                error = OFPERR_OFPBMC_BAD_VALUE;
            } else if (!NXM_HASMASK(header)) {
                error = 0;
                mf_set_value(mf, &value, match);
            } else {
                union mf_value mask;

                memcpy(&mask, p + 4 + width, width);
                if (!mf_is_mask_valid(mf, &mask)) {
                    error = OFPERR_OFPBMC_BAD_MASK;
                } else {
                    error = check_mask_consistency(p, mf);
                    if (!error) {
                        mf_set(mf, &value, &mask, match);
                    }
                }
            }
        }

        /* Check if the match is for a cookie rather than a classifier rule. */
        if ((header == NXM_NX_COOKIE || header == NXM_NX_COOKIE_W) && cookie) {
            if (*cookie_mask) {
                error = OFPERR_OFPBMC_DUP_FIELD;
            } else {
                unsigned int width = sizeof *cookie;

                memcpy(cookie, p + 4, width);
                if (NXM_HASMASK(header)) {
                    memcpy(cookie_mask, p + 4 + width, width);
                } else {
                    *cookie_mask = OVS_BE64_MAX;
                }
                error = 0;
            }
        }

        if (error) {
            VLOG_DBG_RL(&rl, "bad nxm_entry %#08"PRIx32" (vendor=%"PRIu32", "
                        "field=%"PRIu32", hasmask=%"PRIu32", len=%"PRIu32"), "
                        "(%s)", header,
                        NXM_VENDOR(header), NXM_FIELD(header),
                        NXM_HASMASK(header), NXM_LENGTH(header),
                        ofperr_to_string(error));
            return error;
        }
    }

    return match_len ? OFPERR_OFPBMC_BAD_LEN : 0;
}
Example #3
0
/* Parses 'arg' as a set of arguments to the "learn" action and appends a
 * matching NXAST_LEARN action to 'b'.  The format parsed is described in
 * ovs-ofctl(8).
 *
 * Prints an error on stderr and aborts the program if 'arg' syntax is invalid.
 *
 * If 'flow' is nonnull, then it should be the flow from a cls_rule that is
 * the matching rule for the learning action.  This helps to better validate
 * the action's arguments.
 *
 * Modifies 'arg'. */
void
learn_parse(struct ofpbuf *b, char *arg, const struct flow *flow)
{
    char *orig = xstrdup(arg);
    char *name, *value;
    enum ofperr error;
    size_t learn_ofs;
    size_t len;

    struct nx_action_learn *learn;
    struct cls_rule rule;

    learn_ofs = b->size;
    learn = ofputil_put_NXAST_LEARN(b);
    learn->idle_timeout = htons(OFP_FLOW_PERMANENT);
    learn->hard_timeout = htons(OFP_FLOW_PERMANENT);
    learn->priority = htons(OFP_DEFAULT_PRIORITY);
    learn->cookie = htonll(0);
    learn->flags = htons(0);
    learn->table_id = 1;

    cls_rule_init_catchall(&rule, 0);
    while (ofputil_parse_key_value(&arg, &name, &value)) {
        learn = ofpbuf_at_assert(b, learn_ofs, sizeof *learn);
        if (!strcmp(name, "table")) {
            learn->table_id = atoi(value);
            if (learn->table_id == 255) {
                ovs_fatal(0, "%s: table id 255 not valid for `learn' action",
                          orig);
            }
        } else if (!strcmp(name, "priority")) {
            learn->priority = htons(atoi(value));
        } else if (!strcmp(name, "idle_timeout")) {
            learn->idle_timeout = htons(atoi(value));
        } else if (!strcmp(name, "hard_timeout")) {
            learn->hard_timeout = htons(atoi(value));
        } else if (!strcmp(name, "fin_idle_timeout")) {
            learn->fin_idle_timeout = htons(atoi(value));
        } else if (!strcmp(name, "fin_hard_timeout")) {
            learn->fin_hard_timeout = htons(atoi(value));
        } else if (!strcmp(name, "cookie")) {
            learn->cookie = htonll(strtoull(value, NULL, 0));
        } else {
            struct learn_spec spec;

            learn_parse_spec(orig, name, value, &spec);

            /* Check prerequisites. */
            if (spec.src_type == NX_LEARN_SRC_FIELD
                && flow && !mf_are_prereqs_ok(spec.src.field, flow)) {
                ovs_fatal(0, "%s: cannot specify source field %s because "
                          "prerequisites are not satisfied",
                          orig, spec.src.field->name);
            }
            if ((spec.dst_type == NX_LEARN_DST_MATCH
                 || spec.dst_type == NX_LEARN_DST_LOAD)
                && !mf_are_prereqs_ok(spec.dst.field, &rule.flow)) {
                ovs_fatal(0, "%s: cannot specify destination field %s because "
                          "prerequisites are not satisfied",
                          orig, spec.dst.field->name);
            }

            /* Update 'rule' to allow for satisfying destination
             * prerequisites. */
            if (spec.src_type == NX_LEARN_SRC_IMMEDIATE
                && spec.dst_type == NX_LEARN_DST_MATCH) {
                mf_write_subfield(&spec.dst, &spec.src_imm, &rule);
            }

            /* Output the flow_mod_spec. */
            put_u16(b, spec.n_bits | spec.src_type | spec.dst_type);
            if (spec.src_type == NX_LEARN_SRC_IMMEDIATE) {
                int n_bytes = DIV_ROUND_UP(spec.n_bits, 16) * 2;
                int ofs = sizeof spec.src_imm - n_bytes;
                ofpbuf_put(b, &spec.src_imm.u8[ofs], n_bytes);
            } else {
                put_u32(b, spec.src.field->nxm_header);
                put_u16(b, spec.src.ofs);
            }
            if (spec.dst_type == NX_LEARN_DST_MATCH ||
                spec.dst_type == NX_LEARN_DST_LOAD) {
                put_u32(b, spec.dst.field->nxm_header);
                put_u16(b, spec.dst.ofs);
            } else {
                assert(spec.dst_type == NX_LEARN_DST_OUTPUT);
            }
        }
    }

    put_u16(b, 0);

    len = b->size - learn_ofs;
    if (len % 8) {
        ofpbuf_put_zeros(b, 8 - len % 8);
    }

    learn = ofpbuf_at_assert(b, learn_ofs, sizeof *learn);
    learn->len = htons(b->size - learn_ofs);

    /* In theory the above should have caught any errors, but... */
    if (flow) {
        error = learn_check(learn, flow);
        if (error) {
            ovs_fatal(0, "%s: %s", orig, ofperr_to_string(error));
        }
    }
    free(orig);
}
Example #4
0
static void
process_packet_in(struct lswitch *sw, const struct ofp_header *oh)
{
    struct ofputil_packet_in pi;
    uint32_t buffer_id;

    uint64_t ofpacts_stub[64];
    struct ofpbuf ofpacts;

    struct ofputil_packet_out po;
    enum ofperr error;
    uint8_t icmp_packet[128];

    const struct mf_field *mf; 
    const struct mf_field *mf_id; 
    union mf_value sf_value, sf_mask;
    union mf_value sf_value_id, sf_mask_id;

    error = ofputil_decode_packet_in(oh, true, &pi, NULL, &buffer_id, NULL);
    if (error) {
        VLOG_WARN_RL(&rl, "failed to decode packet-in: %s",
                     ofperr_to_string(error));
        return;
    }

    /* Ignore packets sent via output to OFPP_CONTROLLER.  This library never
     * uses such an action.  You never know what experiments might be going on,
     * though, and it seems best not to interfere with them. */
    if (pi.reason != OFPR_ACTION || buffer_id != UINT32_MAX) {
        return;
    }

    struct ethhdr *old_pkt = pi.packet;
   
    struct iphdr * old_ipv4 = (struct iphdr*)(old_pkt + 1);
    uint16_t old_tot_len = ntohs(old_ipv4->tot_len);
    uint8_t header_len = old_ipv4->ihl*4;

    if (pi.packet_len < header_len + sizeof(struct ethhdr) + 8 || old_tot_len < header_len + 8)
        return;

    if (old_pkt->h_proto != htons(ETH_P_IP))
        return;

    //VLOG_INFO("AFTER MATCH");

    uint32_t icmp_packet_len = sizeof(struct ethhdr) + sizeof(struct iphdr) + header_len + sizeof(struct icmphdr) + 8;

    icmp_unexpect_ttl(icmp_packet, &pi, header_len, ICMP_TIME_EXCEEDED, ICMP_EXC_TTL, 0);

    ofpbuf_use_stack(&ofpacts, ofpacts_stub, sizeof ofpacts_stub);

    mf_id = mf_from_name("tun_id");
    if (!mf_id)
        return;

    sf_value_id.be64 = pi.flow_metadata.flow.tunnel.tun_id;
    sf_mask_id.be64 = OVS_BE64_MAX;
    ofpact_put_set_field(&ofpacts, mf_id, &sf_value_id, &sf_mask_id);

    mf = mf_from_name("tun_dst");
    if (!mf)
        return;

    sf_value.be32 = pi.flow_metadata.flow.tunnel.ip_src;
    sf_mask.be32 = OVS_BE32_MAX;
    ofpact_put_set_field(&ofpacts, mf, &sf_value, &sf_mask);

    ofpact_put_OUTPUT(&ofpacts)->port = OFPP_IN_PORT;

    /* Prepare packet_out in case we need one. */
    po.buffer_id = buffer_id;
    po.packet = icmp_packet;
    po.packet_len = icmp_packet_len;

    po.in_port = pi.flow_metadata.flow.in_port.ofp_port;
    po.ofpacts = ofpacts.data;
    po.ofpacts_len = ofpacts.size;


    queue_tx(sw, ofputil_encode_packet_out(&po, sw->protocol));

    //VLOG_INFO("AFTER MATCH last");
}