示例#1
0
static enum ofperr
learn_check_header(uint16_t header, size_t len)
{
    int src_type = header & NX_LEARN_SRC_MASK;
    int dst_type = header & NX_LEARN_DST_MASK;

    /* Check for valid src and dst type combination. */
    if (dst_type == NX_LEARN_DST_MATCH ||
        dst_type == NX_LEARN_DST_LOAD ||
        (dst_type == NX_LEARN_DST_OUTPUT &&
         src_type == NX_LEARN_SRC_FIELD)) {
        /* OK. */
    } else {
        return OFPERR_OFPBAC_BAD_ARGUMENT;
    }

    /* Check that the arguments don't overrun the end of the action. */
    if (len < learn_min_len(header)) {
        return OFPERR_OFPBAC_BAD_LEN;
    }

    return 0;
}
示例#2
0
文件: learn.c 项目: yamt/openvswitch
/* Converts 'nal' into a "struct ofpact_learn" and appends that struct to
 * 'ofpacts'.  Returns 0 if successful, otherwise an OFPERR_*. */
enum ofperr
learn_from_openflow(const struct nx_action_learn *nal, struct ofpbuf *ofpacts)
{
    struct ofpact_learn *learn;
    const void *p, *end;

    if (nal->pad) {
        return OFPERR_OFPBAC_BAD_ARGUMENT;
    }

    learn = ofpact_put_LEARN(ofpacts);

    learn->idle_timeout = ntohs(nal->idle_timeout);
    learn->hard_timeout = ntohs(nal->hard_timeout);
    learn->priority = ntohs(nal->priority);
    learn->cookie = ntohll(nal->cookie);
    learn->flags = ntohs(nal->flags);
    learn->table_id = nal->table_id;
    learn->fin_idle_timeout = ntohs(nal->fin_idle_timeout);
    learn->fin_hard_timeout = ntohs(nal->fin_hard_timeout);

    if (learn->flags & ~OFPFF_SEND_FLOW_REM || learn->table_id == 0xff) {
        return OFPERR_OFPBAC_BAD_ARGUMENT;
    }

    end = (char *) nal + ntohs(nal->len);
    for (p = nal + 1; p != end; ) {
        struct ofpact_learn_spec *spec;
        uint16_t header = ntohs(get_be16(&p));

        if (!header) {
            break;
        }

        spec = ofpbuf_put_zeros(ofpacts, sizeof *spec);
        learn = ofpacts->l2;
        learn->n_specs++;

        spec->src_type = header & NX_LEARN_SRC_MASK;
        spec->dst_type = header & NX_LEARN_DST_MASK;
        spec->n_bits = header & NX_LEARN_N_BITS_MASK;

        /* Check for valid src and dst type combination. */
        if (spec->dst_type == NX_LEARN_DST_MATCH ||
                spec->dst_type == NX_LEARN_DST_LOAD ||
                (spec->dst_type == NX_LEARN_DST_OUTPUT &&
                 spec->src_type == NX_LEARN_SRC_FIELD)) {
            /* OK. */
        } else {
            return OFPERR_OFPBAC_BAD_ARGUMENT;
        }

        /* Check that the arguments don't overrun the end of the action. */
        if ((char *) end - (char *) p < learn_min_len(header)) {
            return OFPERR_OFPBAC_BAD_LEN;
        }

        /* Get the source. */
        if (spec->src_type == NX_LEARN_SRC_FIELD) {
            get_subfield(spec->n_bits, &p, &spec->src);
        } else {
            int p_bytes = 2 * DIV_ROUND_UP(spec->n_bits, 16);

            bitwise_copy(p, p_bytes, 0,
                         &spec->src_imm, sizeof spec->src_imm, 0,
                         spec->n_bits);
            p = (const uint8_t *) p + p_bytes;
        }

        /* Get the destination. */
        if (spec->dst_type == NX_LEARN_DST_MATCH ||
                spec->dst_type == NX_LEARN_DST_LOAD) {
            get_subfield(spec->n_bits, &p, &spec->dst);
        }
    }
    ofpact_update_len(ofpacts, &learn->ofpact);

    if (!is_all_zeros(p, (char *) end - (char *) p)) {
        return OFPERR_OFPBAC_BAD_ARGUMENT;
    }

    return 0;
}
示例#3
0
void
learn_format(const struct nx_action_learn *learn, struct ds *s)
{
    struct cls_rule rule;
    const void *p, *end;

    cls_rule_init_catchall(&rule, 0);

    ds_put_format(s, "learn(table=%"PRIu8, learn->table_id);
    if (learn->idle_timeout != htons(OFP_FLOW_PERMANENT)) {
        ds_put_format(s, ",idle_timeout=%"PRIu16, ntohs(learn->idle_timeout));
    }
    if (learn->hard_timeout != htons(OFP_FLOW_PERMANENT)) {
        ds_put_format(s, ",hard_timeout=%"PRIu16, ntohs(learn->hard_timeout));
    }
    if (learn->fin_idle_timeout) {
        ds_put_format(s, ",fin_idle_timeout=%"PRIu16,
                      ntohs(learn->fin_idle_timeout));
    }
    if (learn->fin_hard_timeout) {
        ds_put_format(s, ",fin_hard_timeout=%"PRIu16,
                      ntohs(learn->fin_hard_timeout));
    }
    if (learn->priority != htons(OFP_DEFAULT_PRIORITY)) {
        ds_put_format(s, ",priority=%"PRIu16, ntohs(learn->priority));
    }
    if (learn->flags & htons(OFPFF_SEND_FLOW_REM)) {
        ds_put_cstr(s, ",OFPFF_SEND_FLOW_REM");
    }
    if (learn->flags & htons(~OFPFF_SEND_FLOW_REM)) {
        ds_put_format(s, ",***flags=%"PRIu16"***",
                      ntohs(learn->flags) & ~OFPFF_SEND_FLOW_REM);
    }
    if (learn->cookie != htonll(0)) {
        ds_put_format(s, ",cookie=0x%"PRIx64, ntohll(learn->cookie));
    }
    if (learn->pad != 0) {
        ds_put_cstr(s, ",***nonzero pad***");
    }

    end = (char *) learn + ntohs(learn->len);
    for (p = learn + 1; p != end; ) {
        uint16_t header = ntohs(get_be16(&p));
        int n_bits = header & NX_LEARN_N_BITS_MASK;

        int src_type = header & NX_LEARN_SRC_MASK;
        struct mf_subfield src;
        const uint8_t *src_value;
        int src_value_bytes;

        int dst_type = header & NX_LEARN_DST_MASK;
        struct mf_subfield dst;

        enum ofperr error;
        int i;

        if (!header) {
            break;
        }

        error = learn_check_header(header, (char *) end - (char *) p);
        if (error == OFPERR_OFPBAC_BAD_ARGUMENT) {
            ds_put_format(s, ",***bad flow_mod_spec header %"PRIx16"***)",
                          header);
            return;
        } else if (error == OFPERR_OFPBAC_BAD_LEN) {
            ds_put_format(s, ",***flow_mod_spec at offset %td is %u bytes "
                          "long but only %td bytes are left***)",
                          (char *) p - (char *) (learn + 1) - 2,
                          learn_min_len(header) + 2,
                          (char *) end - (char *) p + 2);
            return;
        }
        assert(!error);

        /* Get the source. */
        if (src_type == NX_LEARN_SRC_FIELD) {
            get_subfield(n_bits, &p, &src);
            src_value_bytes = 0;
            src_value = NULL;
        } else {
            src.field = NULL;
            src.ofs = 0;
            src.n_bits = 0;
            src_value_bytes = 2 * DIV_ROUND_UP(n_bits, 16);
            src_value = p;
            p = (const void *) ((const uint8_t *) p + src_value_bytes);
        }

        /* Get the destination. */
        if (dst_type == NX_LEARN_DST_MATCH || dst_type == NX_LEARN_DST_LOAD) {
            get_subfield(n_bits, &p, &dst);
        } else {
            dst.field = NULL;
            dst.ofs = 0;
            dst.n_bits = 0;
        }

        ds_put_char(s, ',');

        switch (src_type | dst_type) {
        case NX_LEARN_SRC_IMMEDIATE | NX_LEARN_DST_MATCH:
            if (dst.field && dst.ofs == 0 && n_bits == dst.field->n_bits) {
                union mf_value value;
                uint8_t *bytes = (uint8_t *) &value;

                if (src_value_bytes > dst.field->n_bytes) {
                    /* The destination field is an odd number of bytes, which
                     * got rounded up to a multiple of 2 to be put into the
                     * learning action.  Skip over the leading byte, which
                     * should be zero anyway.  Otherwise the memcpy() below
                     * will overrun the start of 'value'. */
                    int diff = src_value_bytes - dst.field->n_bytes;
                    src_value += diff;
                    src_value_bytes -= diff;
                }

                memset(&value, 0, sizeof value);
                memcpy(&bytes[dst.field->n_bytes - src_value_bytes],
                       src_value, src_value_bytes);
                ds_put_format(s, "%s=", dst.field->name);
                mf_format(dst.field, &value, NULL, s);
            } else {
                mf_format_subfield(&dst, s);
                ds_put_cstr(s, "=0x");
                for (i = 0; i < src_value_bytes; i++) {
                    ds_put_format(s, "%02"PRIx8, src_value[i]);
                }
            }
            break;

        case NX_LEARN_SRC_FIELD | NX_LEARN_DST_MATCH:
            mf_format_subfield(&dst, s);
            if (src.field != dst.field || src.ofs != dst.ofs) {
                ds_put_char(s, '=');
                mf_format_subfield(&src, s);
            }
            break;

        case NX_LEARN_SRC_IMMEDIATE | NX_LEARN_DST_LOAD:
            ds_put_cstr(s, "load:0x");
            for (i = 0; i < src_value_bytes; i++) {
                ds_put_format(s, "%02"PRIx8, src_value[i]);
            }
            ds_put_cstr(s, "->");
            mf_format_subfield(&dst, s);
            break;

        case NX_LEARN_SRC_FIELD | NX_LEARN_DST_LOAD:
            ds_put_cstr(s, "load:");
            mf_format_subfield(&src, s);
            ds_put_cstr(s, "->");
            mf_format_subfield(&dst, s);
            break;

        case NX_LEARN_SRC_FIELD | NX_LEARN_DST_OUTPUT:
            ds_put_cstr(s, "output:");
            mf_format_subfield(&src, s);
            break;
        }
    }
    if (!is_all_zeros(p, (char *) end - (char *) p)) {
        ds_put_cstr(s, ",***nonzero trailer***");
    }
    ds_put_char(s, ')');
}