--- /dev/null
+/*
+ * Copyright (c) 2012 Nicira, Inc.
+ *
+ * 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-msgs.h"
+#include <assert.h>
+#include "byte-order.h"
+#include "dynamic-string.h"
+#include "hash.h"
+#include "hmap.h"
+#include "ofpbuf.h"
+#include "openflow/nicira-ext.h"
+#include "openflow/openflow.h"
+#include "vlog.h"
+
+VLOG_DEFINE_THIS_MODULE(ofp_msgs);
+
+#define OFPT_VENDOR 4
+#define OFPT10_STATS_REQUEST 16
+#define OFPT10_STATS_REPLY 17
+#define OFPT11_STATS_REQUEST 18
+#define OFPT11_STATS_REPLY 19
+#define OFPST_VENDOR 0xffff
+
+/* A thin abstraction of OpenFlow headers:
+ *
+ * - 'version' and 'type' come straight from struct ofp_header, so these are
+ * always present and meaningful.
+ *
+ * - 'stat' comes from the 'type' member in statistics messages only. It is
+ * meaningful, therefore, only if 'version' and 'type' taken together
+ * specify a statistics request or reply. Otherwise it is 0.
+ *
+ * - 'vendor' is meaningful only for vendor messages, that is, if 'version'
+ * and 'type' specify a vendor message or if 'version' and 'type' specify
+ * a statistics message and 'stat' specifies a vendor statistic type.
+ * Otherwise it is 0.
+ *
+ * - 'subtype' is meaningful only for vendor messages and otherwise 0. It
+ * specifies a vendor-defined subtype. There is no standard format for
+ * these but 32 bits seems like it should be enough. */
+struct ofphdrs {
+ uint8_t version; /* From ofp_header. */
+ uint8_t type; /* From ofp_header. */
+ uint16_t stat; /* From ofp10_stats_msg or ofp11_stats_msg. */
+ uint32_t vendor; /* From ofp_vendor_header,
+ * ofp10_vendor_stats_msg, or
+ * ofp11_vendor_stats_msg. */
+ uint32_t subtype; /* From nicira_header, nicira10_stats_msg, or
+ * nicira11_stats_msg. */
+};
+BUILD_ASSERT_DECL(sizeof(struct ofphdrs) == 12);
+
+/* A mapping from OpenFlow headers to OFPRAW_*. */
+struct raw_instance {
+ struct hmap_node hmap_node; /* In 'raw_instance_map'. */
+ struct ofphdrs hdrs; /* Key. */
+ enum ofpraw raw; /* Value. */
+ unsigned int hdrs_len; /* ofphdrs_len(hdrs). */
+};
+
+/* Information about a particular 'enum ofpraw'. */
+struct raw_info {
+ /* All possible instantiations of this OFPRAW_* into OpenFlow headers. */
+ struct raw_instance *instances; /* min_version - max_version + 1 elems. */
+ uint8_t min_version;
+ uint8_t max_version;
+
+ unsigned int min_body;
+ unsigned int extra_multiple;
+ enum ofptype type;
+ const char *name;
+};
+
+/* All understood OpenFlow message types, indexed by their 'struct ofphdrs'. */
+static struct hmap raw_instance_map;
+#include "ofp-msgs.inc"
+
+static ovs_be32 alloc_xid(void);
+
+/* ofphdrs functions. */
+static uint32_t ofphdrs_hash(const struct ofphdrs *);
+static bool ofphdrs_equal(const struct ofphdrs *a, const struct ofphdrs *b);
+static enum ofperr ofphdrs_decode(struct ofphdrs *,
+ const struct ofp_header *oh, size_t length);
+static void ofphdrs_decode_assert(struct ofphdrs *,
+ const struct ofp_header *oh, size_t length);
+size_t ofphdrs_len(const struct ofphdrs *);
+
+static const struct raw_info *raw_info_get(enum ofpraw);
+static struct raw_instance *raw_instance_get(const struct raw_info *,
+ uint8_t version);
+
+static enum ofperr ofpraw_from_ofphdrs(enum ofpraw *, const struct ofphdrs *);
+\f
+/* Returns a transaction ID to use for an outgoing OpenFlow message. */
+static ovs_be32
+alloc_xid(void)
+{
+ static uint32_t next_xid = 1;
+ return htonl(next_xid++);
+}
+\f
+static uint32_t
+ofphdrs_hash(const struct ofphdrs *hdrs)
+{
+ BUILD_ASSERT_DECL(sizeof *hdrs == 12);
+ return hash_words((const uint32_t *) hdrs, 3, 0);
+}
+
+static bool
+ofphdrs_equal(const struct ofphdrs *a, const struct ofphdrs *b)
+{
+ return !memcmp(a, b, sizeof *a);
+}
+
+static void
+log_bad_vendor(uint32_t vendor)
+{
+ static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 1);
+
+ VLOG_WARN_RL(&rl, "OpenFlow message has unknown vendor %#"PRIx32, vendor);
+}
+
+static enum ofperr
+ofphdrs_decode(struct ofphdrs *hdrs,
+ const struct ofp_header *oh, size_t length)
+{
+ memset(hdrs, 0, sizeof *hdrs);
+ if (length < sizeof *oh) {
+ return OFPERR_OFPBRC_BAD_LEN;
+ }
+
+ /* Get base message version and type (OFPT_*). */
+ hdrs->version = oh->version;
+ hdrs->type = oh->type;
+
+ if (hdrs->type == OFPT_VENDOR) {
+ /* Get vendor. */
+ const struct ofp_vendor_header *ovh;
+
+ if (length < sizeof *ovh) {
+ return OFPERR_OFPBRC_BAD_LEN;
+ }
+
+ ovh = (const struct ofp_vendor_header *) oh;
+ hdrs->vendor = ntohl(ovh->vendor);
+ if (hdrs->vendor == NX_VENDOR_ID) {
+ /* Get Nicira message subtype (NXT_*). */
+ const struct nicira_header *nh;
+
+ if (length < sizeof *nh) {
+ return OFPERR_OFPBRC_BAD_LEN;
+ }
+ nh = (const struct nicira_header *) oh;
+ hdrs->subtype = ntohl(nh->subtype);
+ } else {
+ log_bad_vendor(hdrs->vendor);
+ return OFPERR_OFPBRC_BAD_VENDOR;
+ }
+ } else if (hdrs->version == OFP10_VERSION
+ && (hdrs->type == OFPT10_STATS_REQUEST ||
+ hdrs->type == OFPT10_STATS_REPLY)) {
+ const struct ofp_stats_msg *osm;
+
+ /* Get statistic type (OFPST_*). */
+ if (length < sizeof *osm) {
+ return OFPERR_OFPBRC_BAD_LEN;
+ }
+ osm = (const struct ofp_stats_msg *) oh;
+ hdrs->stat = ntohs(osm->type);
+
+ if (hdrs->stat == OFPST_VENDOR) {
+ /* Get vendor. */
+ const struct ofp10_vendor_stats_msg *ovsm;
+
+ if (length < sizeof *ovsm) {
+ return OFPERR_OFPBRC_BAD_LEN;
+ }
+
+ ovsm = (const struct ofp10_vendor_stats_msg *) oh;
+ hdrs->vendor = ntohl(ovsm->vendor);
+ if (hdrs->vendor == NX_VENDOR_ID) {
+ /* Get Nicira statistic type (NXST_*). */
+ const struct nicira10_stats_msg *nsm;
+
+ if (length < sizeof *nsm) {
+ return OFPERR_OFPBRC_BAD_LEN;
+ }
+ nsm = (const struct nicira10_stats_msg *) oh;
+ hdrs->subtype = ntohl(nsm->subtype);
+ } else {
+ log_bad_vendor(hdrs->vendor);
+ return OFPERR_OFPBRC_BAD_VENDOR;
+ }
+ }
+ } else if (hdrs->version != OFP10_VERSION
+ && (hdrs->type == OFPT11_STATS_REQUEST ||
+ hdrs->type == OFPT11_STATS_REPLY)) {
+ const struct ofp11_stats_msg *osm;
+
+ /* Get statistic type (OFPST_*). */
+ if (length < sizeof *osm) {
+ return OFPERR_OFPBRC_BAD_LEN;
+ }
+ osm = (const struct ofp11_stats_msg *) oh;
+ hdrs->stat = ntohs(osm->type);
+
+ if (hdrs->stat == OFPST_VENDOR) {
+ /* Get vendor. */
+ const struct ofp11_vendor_stats_msg *ovsm;
+
+ if (length < sizeof *ovsm) {
+ return OFPERR_OFPBRC_BAD_LEN;
+ }
+
+ ovsm = (const struct ofp11_vendor_stats_msg *) oh;
+ hdrs->vendor = ntohl(ovsm->vendor);
+ if (hdrs->vendor == NX_VENDOR_ID) {
+ /* Get Nicira statistic type (NXST_*). */
+ const struct nicira11_stats_msg *nsm;
+
+ if (length < sizeof *nsm) {
+ return OFPERR_OFPBRC_BAD_LEN;
+ }
+ nsm = (const struct nicira11_stats_msg *) oh;
+ hdrs->subtype = ntohl(nsm->subtype);
+ } else {
+ log_bad_vendor(hdrs->vendor);
+ return OFPERR_OFPBRC_BAD_VENDOR;
+ }
+ }
+ }
+
+ return 0;
+}
+
+static void
+ofphdrs_decode_assert(struct ofphdrs *hdrs,
+ const struct ofp_header *oh, size_t length)
+{
+ enum ofperr error = ofphdrs_decode(hdrs, oh, length);
+ assert(!error);
+}
+
+static bool
+ofphdrs_is_stat(const struct ofphdrs *hdrs)
+{
+ return (hdrs->version == OFP10_VERSION
+ ? (hdrs->type == OFPT10_STATS_REQUEST ||
+ hdrs->type == OFPT10_STATS_REPLY)
+ : (hdrs->type == OFPT11_STATS_REQUEST ||
+ hdrs->type == OFPT11_STATS_REPLY));
+}
+
+size_t
+ofphdrs_len(const struct ofphdrs *hdrs)
+{
+ if (hdrs->type == OFPT_VENDOR) {
+ return sizeof(struct nicira_header);
+ }
+
+ if (hdrs->version == OFP10_VERSION) {
+ if (hdrs->type == OFPT10_STATS_REQUEST ||
+ hdrs->type == OFPT10_STATS_REPLY) {
+ return (hdrs->stat == OFPST_VENDOR
+ ? sizeof(struct nicira10_stats_msg)
+ : sizeof(struct ofp_stats_msg));
+ }
+ } else {
+ if (hdrs->type == OFPT11_STATS_REQUEST ||
+ hdrs->type == OFPT11_STATS_REPLY) {
+ return (hdrs->stat == OFPST_VENDOR
+ ? sizeof(struct nicira11_stats_msg)
+ : sizeof(struct ofp11_stats_msg));
+ }
+ }
+
+ return sizeof(struct ofp_header);
+}
+\f
+/* Determines the OFPRAW_* type of the OpenFlow message at 'oh', which has
+ * length 'oh->length'. (The caller must ensure that 'oh->length' bytes of
+ * data are readable at 'oh'.) On success, returns 0 and stores the type into
+ * '*raw'. On failure, returns an OFPERR_* error code and zeros '*raw'.
+ *
+ * This function checks that 'oh' is a valid length for its particular type of
+ * message, and returns an error if not. */
+enum ofperr
+ofpraw_decode(enum ofpraw *raw, const struct ofp_header *oh)
+{
+ struct ofpbuf msg;
+
+ ofpbuf_use_const(&msg, oh, ntohs(oh->length));
+ return ofpraw_pull(raw, &msg);
+}
+
+/* Determines the OFPRAW_* type of the OpenFlow message in 'msg', which starts
+ * at 'msg->data' and has length 'msg->size' bytes. On success, returns 0 and
+ * stores the type into '*rawp'. On failure, returns an OFPERR_* error code
+ * and zeros '*rawp'.
+ *
+ * This function checks that the message has a valid length for its particular
+ * type of message, and returns an error if not.
+ *
+ * In addition to setting '*rawp', this function pulls off the OpenFlow header
+ * (including the stats headers, vendor header, and any subtype header) with
+ * ofpbuf_pull(). It also sets 'msg->l2' to the start of the OpenFlow header
+ * and 'msg->l3' just beyond the headers (that is, to the final value of
+ * msg->data). */
+enum ofperr
+ofpraw_pull(enum ofpraw *rawp, struct ofpbuf *msg)
+{
+ static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 5);
+
+ const struct raw_instance *instance;
+ const struct raw_info *info;
+ struct ofphdrs hdrs;
+
+ unsigned int min_len;
+ unsigned int len;
+
+ enum ofperr error;
+ enum ofpraw raw;
+
+ /* Set default outputs. */
+ msg->l2 = msg->l3 = msg->data;
+ *rawp = 0;
+
+ len = msg->size;
+ error = ofphdrs_decode(&hdrs, msg->data, len);
+ if (error) {
+ return error;
+ }
+
+ error = ofpraw_from_ofphdrs(&raw, &hdrs);
+ if (error) {
+ return error;
+ }
+
+ info = raw_info_get(raw);
+ instance = raw_instance_get(info, hdrs.version);
+ msg->l2 = ofpbuf_pull(msg, instance->hdrs_len);
+ msg->l3 = msg->data;
+
+ min_len = instance->hdrs_len + info->min_body;
+ switch (info->extra_multiple) {
+ case 0:
+ if (len != min_len) {
+ VLOG_WARN_RL(&rl, "received %s with incorrect length %u (expected "
+ "length %u)", info->name, len, min_len);
+ return OFPERR_OFPBRC_BAD_LEN;
+ }
+ break;
+
+ case 1:
+ if (len < min_len) {
+ VLOG_WARN_RL(&rl, "received %s with incorrect length %u (expected "
+ "length at least %u bytes)",
+ info->name, len, min_len);
+ return OFPERR_OFPBRC_BAD_LEN;
+ }
+ break;
+
+ default:
+ if (len < min_len || (len - min_len) % info->extra_multiple) {
+ VLOG_WARN_RL(&rl, "received %s with incorrect length %u (must be "
+ "exactly %u bytes or longer by an integer multiple "
+ "of %u bytes)",
+ info->name, len, min_len, info->extra_multiple);
+ return OFPERR_OFPBRC_BAD_LEN;
+ }
+ break;
+ }
+
+ *rawp = raw;
+ return 0;
+}
+
+/* Does the same job as ofpraw_pull(), except that it assert-fails if
+ * ofpbuf_pull() would have reported an error. Thus, it's able to use the
+ * return value for the OFPRAW_* message type instead of an error code.
+ *
+ * (It only makes sense to use this function if you previously called
+ * ofpbuf_decode() on the message and thus know that it's OK.) */
+enum ofpraw
+ofpraw_pull_assert(struct ofpbuf *msg)
+{
+ enum ofperr error;
+ enum ofpraw raw;
+
+ error = ofpraw_pull(&raw, msg);
+ assert(!error);
+ return raw;
+}
+
+/* Determines the OFPRAW_* type of the OpenFlow message that starts at 'oh' and
+ * has length 'length' bytes. On success, returns 0 and stores the type into
+ * '*rawp'. On failure, returns an OFPERR_* error code and zeros '*rawp'.
+ *
+ * Unlike other functions for decoding message types, this one is not picky
+ * about message length. For example, it will successfully decode a message
+ * whose body is shorter than the minimum length for a message of its type.
+ * Thus, this is the correct function to use for decoding the type of a message
+ * that might have been truncated, such as the payload of an OpenFlow error
+ * message (which is allowed to be truncated to 64 bytes). */
+enum ofperr
+ofpraw_decode_partial(enum ofpraw *raw,
+ const struct ofp_header *oh, size_t length)
+{
+ struct ofphdrs hdrs;
+ enum ofperr error;
+
+ error = ofphdrs_decode(&hdrs, oh, length);
+ if (!error) {
+ error = ofpraw_from_ofphdrs(raw, &hdrs);
+ }
+
+ if (error) {
+ *raw = 0;
+ }
+ return error;
+}
+\f
+/* Encoding messages using OFPRAW_* values. */
+
+static void ofpraw_put__(enum ofpraw, uint8_t version, ovs_be32 xid,
+ size_t extra_tailroom, struct ofpbuf *);
+
+/* Allocates and returns a new ofpbuf that contains an OpenFlow header for
+ * 'raw' with OpenFlow version 'version' and a fresh OpenFlow transaction ID.
+ * The ofpbuf has enough tailroom for the minimum body length of 'raw', plus
+ * 'extra_tailroom' additional bytes.
+ *
+ * Each 'raw' value is valid only for certain OpenFlow versions. The caller
+ * must specify a valid (raw, version) pair.
+ *
+ * In the returned ofpbuf, 'l2' points to the beginning of the OpenFlow header
+ * and 'l3' points just after it, to where the message's body will start. The
+ * caller must actually allocate the body into the space reserved for it,
+ * e.g. with ofpbuf_put_uninit().
+ *
+ * The caller owns the returned ofpbuf and must free it when it is no longer
+ * needed, e.g. with ofpbuf_delete(). */
+struct ofpbuf *
+ofpraw_alloc(enum ofpraw raw, uint8_t version, size_t extra_tailroom)
+{
+ return ofpraw_alloc_xid(raw, version, alloc_xid(), extra_tailroom);
+}
+
+/* Same as ofpraw_alloc() but the caller provides the transaction ID. */
+struct ofpbuf *
+ofpraw_alloc_xid(enum ofpraw raw, uint8_t version, ovs_be32 xid,
+ size_t extra_tailroom)
+{
+ struct ofpbuf *buf = ofpbuf_new(0);
+ ofpraw_put__(raw, version, xid, extra_tailroom, buf);
+ return buf;
+}
+
+/* Same as ofpraw_alloc(), but obtains the OpenFlow version and transaction ID
+ * from 'request->version' and 'request->xid', respectively.
+ *
+ * Even though the version comes from 'request->version', the caller must still
+ * know what it is doing, by specifying a valid pairing of 'raw' and
+ * 'request->version', just like ofpraw_alloc(). */
+struct ofpbuf *
+ofpraw_alloc_reply(enum ofpraw raw, const struct ofp_header *request,
+ size_t extra_tailroom)
+{
+ return ofpraw_alloc_xid(raw, request->version, request->xid,
+ extra_tailroom);
+}
+
+/* Allocates and returns a new ofpbuf that contains an OpenFlow header that is
+ * a stats reply to the stats request in 'request', using the same OpenFlow
+ * version and transaction ID as 'request'. The ofpbuf has enough tailroom for
+ * the stats reply's minimum body length, plus 'extra_tailroom' additional
+ * bytes.
+ *
+ * 'request' must be a stats request, that is, an OFPRAW_OFPST* or OFPRAW_NXST*
+ * value. Every stats request has a corresponding reply, so the (raw, version)
+ * pairing pitfalls of the other ofpraw_alloc_*() functions don't apply here.
+ *
+ * In the returned ofpbuf, 'l2' points to the beginning of the OpenFlow header
+ * and 'l3' points just after it, to where the message's body will start. The
+ * caller must actually allocate the body into the space reserved for it,
+ * e.g. with ofpbuf_put_uninit().
+ *
+ * The caller owns the returned ofpbuf and must free it when it is no longer
+ * needed, e.g. with ofpbuf_delete(). */
+struct ofpbuf *
+ofpraw_alloc_stats_reply(const struct ofp_header *request,
+ size_t extra_tailroom)
+{
+ enum ofpraw request_raw;
+ enum ofpraw reply_raw;
+ enum ofperr error;
+
+ error = ofpraw_decode_partial(&request_raw, request,
+ ntohs(request->length));
+ assert(!error);
+
+ reply_raw = ofpraw_stats_request_to_reply(request_raw, request->version);
+ assert(reply_raw);
+
+ return ofpraw_alloc_reply(reply_raw, request, extra_tailroom);
+}
+
+/* Appends to 'buf' an OpenFlow header for 'raw' with OpenFlow version
+ * 'version' and a fresh OpenFlow transaction ID. Preallocates enough tailroom
+ * in 'buf' for the minimum body length of 'raw', plus 'extra_tailroom'
+ * additional bytes.
+ *
+ * Each 'raw' value is valid only for certain OpenFlow versions. The caller
+ * must specify a valid (raw, version) pair.
+ *
+ * Upon return, 'buf->l2' points to the beginning of the OpenFlow header and
+ * 'buf->l3' points just after it, to where the message's body will start. The
+ * caller must actually allocating the body into the space reserved for it,
+ * e.g. with ofpbuf_put_uninit(). */
+void
+ofpraw_put(enum ofpraw raw, uint8_t version, struct ofpbuf *buf)
+{
+ ofpraw_put__(raw, version, alloc_xid(), 0, buf);
+}
+
+/* Same as ofpraw_put() but the caller provides the transaction ID. */
+void
+ofpraw_put_xid(enum ofpraw raw, uint8_t version, ovs_be32 xid,
+ struct ofpbuf *buf)
+{
+ ofpraw_put__(raw, version, xid, 0, buf);
+}
+
+/* Same as ofpraw_put(), but obtains the OpenFlow version and transaction ID
+ * from 'request->version' and 'request->xid', respectively.
+ *
+ * Even though the version comes from 'request->version', the caller must still
+ * know what it is doing, by specifying a valid pairing of 'raw' and
+ * 'request->version', just like ofpraw_put(). */
+void
+ofpraw_put_reply(enum ofpraw raw, const struct ofp_header *request,
+ struct ofpbuf *buf)
+{
+ ofpraw_put__(raw, request->version, request->xid, 0, buf);
+}
+
+/* Appends to 'buf' an OpenFlow header that is a stats reply to the stats
+ * request in 'request', using the same OpenFlow version and transaction ID as
+ * 'request'. Preallocate enough tailroom in 'buf for the stats reply's
+ * minimum body length, plus 'extra_tailroom' additional bytes.
+ *
+ * 'request' must be a stats request, that is, an OFPRAW_OFPST* or OFPRAW_NXST*
+ * value. Every stats request has a corresponding reply, so the (raw, version)
+ * pairing pitfalls of the other ofpraw_alloc_*() functions don't apply here.
+ *
+ * In the returned ofpbuf, 'l2' points to the beginning of the OpenFlow header
+ * and 'l3' points just after it, to where the message's body will start. The
+ * caller must actually allocate the body into the space reserved for it,
+ * e.g. with ofpbuf_put_uninit().
+ *
+ * The caller owns the returned ofpbuf and must free it when it is no longer
+ * needed, e.g. with ofpbuf_delete(). */
+void
+ofpraw_put_stats_reply(const struct ofp_header *request, struct ofpbuf *buf)
+{
+ enum ofperr error;
+ enum ofpraw raw;
+
+ error = ofpraw_decode_partial(&raw, request, ntohs(request->length));
+ assert(!error);
+
+ raw = ofpraw_stats_request_to_reply(raw, request->version);
+ assert(raw);
+
+ ofpraw_put__(raw, request->version, request->xid, 0, buf);
+}
+
+static void
+ofpraw_put__(enum ofpraw raw, uint8_t version, ovs_be32 xid,
+ size_t extra_tailroom, struct ofpbuf *buf)
+{
+ const struct raw_info *info = raw_info_get(raw);
+ const struct raw_instance *instance = raw_instance_get(info, version);
+ const struct ofphdrs *hdrs = &instance->hdrs;
+ struct ofp_header *oh;
+
+ ofpbuf_prealloc_tailroom(buf, (instance->hdrs_len + info->min_body
+ + extra_tailroom));
+ buf->l2 = ofpbuf_put_uninit(buf, instance->hdrs_len);
+ buf->l3 = ofpbuf_tail(buf);
+
+ oh = buf->l2;
+ oh->version = version;
+ oh->type = hdrs->type;
+ oh->length = htons(buf->size);
+ oh->xid = xid;
+
+ if (hdrs->type == OFPT_VENDOR) {
+ struct nicira_header *nh = buf->l2;
+
+ assert(hdrs->vendor == NX_VENDOR_ID);
+ nh->vendor = htonl(hdrs->vendor);
+ nh->subtype = htonl(hdrs->subtype);
+ } else if (version == OFP10_VERSION
+ && (hdrs->type == OFPT10_STATS_REQUEST ||
+ hdrs->type == OFPT10_STATS_REPLY)) {
+ struct ofp_stats_msg *osm = buf->l2;
+
+ osm->type = htons(hdrs->stat);
+ osm->flags = htons(0);
+
+ if (hdrs->stat == OFPST_VENDOR) {
+ struct ofp10_vendor_stats_msg *ovsm = buf->l2;
+
+ ovsm->vendor = htonl(hdrs->vendor);
+ if (hdrs->vendor == NX_VENDOR_ID) {
+ struct nicira10_stats_msg *nsm = buf->l2;
+
+ nsm->subtype = htonl(hdrs->subtype);
+ memset(nsm->pad, 0, sizeof nsm->pad);
+ } else {
+ NOT_REACHED();
+ }
+ }
+ } else if (version != OFP10_VERSION
+ && (hdrs->type == OFPT11_STATS_REQUEST ||
+ hdrs->type == OFPT11_STATS_REPLY)) {
+ struct ofp11_stats_msg *osm = buf->l2;
+
+ osm->type = htons(hdrs->stat);
+ osm->flags = htons(0);
+ memset(osm->pad, 0, sizeof osm->pad);
+
+ if (hdrs->stat == OFPST_VENDOR) {
+ struct ofp11_vendor_stats_msg *ovsm = buf->l2;
+
+ ovsm->vendor = htonl(hdrs->vendor);
+ if (hdrs->vendor == NX_VENDOR_ID) {
+ struct nicira11_stats_msg *nsm = buf->l2;
+
+ nsm->subtype = htonl(hdrs->subtype);
+ } else {
+ NOT_REACHED();
+ }
+ }
+ }
+}
+\f
+/* Returns 'raw''s name.
+ *
+ * The name is the name used for 'raw' in the OpenFlow specification. For
+ * example, ofpraw_get_name(OFPRAW_OFPT10_FEATURES_REPLY) is
+ * "OFPT_FEATURES_REPLY".
+ *
+ * The caller must not modify or free the returned string. */
+const char *
+ofpraw_get_name(enum ofpraw raw)
+{
+ return raw_info_get(raw)->name;
+}
+
+/* Returns the stats reply that corresponds to 'raw' in the given OpenFlow
+ * 'version'. */
+enum ofpraw
+ofpraw_stats_request_to_reply(enum ofpraw raw, uint8_t version)
+{
+ const struct raw_info *info = raw_info_get(raw);
+ const struct raw_instance *instance = raw_instance_get(info, version);
+ enum ofpraw reply_raw;
+ struct ofphdrs hdrs;
+ enum ofperr error;
+
+ hdrs = instance->hdrs;
+ if (hdrs.version == OFP10_VERSION) {
+ assert(hdrs.type == OFPT10_STATS_REQUEST);
+ hdrs.type = OFPT10_STATS_REPLY;
+ } else {
+ assert(hdrs.type == OFPT11_STATS_REQUEST);
+ hdrs.type = OFPT11_STATS_REPLY;
+ }
+
+ error = ofpraw_from_ofphdrs(&reply_raw, &hdrs);
+ assert(!error);
+
+ return reply_raw;
+}
+\f
+/* Determines the OFPTYPE_* type of the OpenFlow message at 'oh', which has
+ * length 'oh->length'. (The caller must ensure that 'oh->length' bytes of
+ * data are readable at 'oh'.) On success, returns 0 and stores the type into
+ * '*typep'. On failure, returns an OFPERR_* error code and zeros '*typep'.
+ *
+ * This function checks that 'oh' is a valid length for its particular type of
+ * message, and returns an error if not. */
+enum ofperr
+ofptype_decode(enum ofptype *typep, const struct ofp_header *oh)
+{
+ enum ofperr error;
+ enum ofpraw raw;
+
+ error = ofpraw_decode(&raw, oh);
+ *typep = error ? 0 : ofptype_from_ofpraw(raw);
+ return error;
+}
+
+/* Determines the OFPTYPE_* type of the OpenFlow message in 'msg', which starts
+ * at 'msg->data' and has length 'msg->size' bytes. On success, returns 0 and
+ * stores the type into '*typep'. On failure, returns an OFPERR_* error code
+ * and zeros '*typep'.
+ *
+ * This function checks that the message has a valid length for its particular
+ * type of message, and returns an error if not.
+ *
+ * In addition to setting '*typep', this function pulls off the OpenFlow header
+ * (including the stats headers, vendor header, and any subtype header) with
+ * ofpbuf_pull(). It also sets 'msg->l2' to the start of the OpenFlow header
+ * and 'msg->l3' just beyond the headers (that is, to the final value of
+ * msg->data). */
+enum ofperr
+ofptype_pull(enum ofptype *typep, struct ofpbuf *buf)
+{
+ enum ofperr error;
+ enum ofpraw raw;
+
+ error = ofpraw_pull(&raw, buf);
+ *typep = error ? 0 : ofptype_from_ofpraw(raw);
+ return error;
+}
+
+/* Returns the OFPTYPE_* type that corresponds to 'raw'.
+ *
+ * (This is a one-way trip, because the mapping from ofpraw to ofptype is
+ * many-to-one.) */
+enum ofptype
+ofptype_from_ofpraw(enum ofpraw raw)
+{
+ return raw_info_get(raw)->type;
+}
+\f
+/* Updates the 'length' field of the OpenFlow message in 'buf' to
+ * 'buf->size'. */
+void
+ofpmsg_update_length(struct ofpbuf *buf)
+{
+ struct ofp_header *oh = ofpbuf_at_assert(buf, 0, sizeof *oh);
+ oh->length = htons(buf->size);
+}
+
+/* Returns just past the Openflow header (including the stats headers, vendor
+ * header, and any subtype header) in 'oh'. */
+const void *
+ofpmsg_body(const struct ofp_header *oh)
+{
+ struct ofphdrs hdrs;
+
+ ofphdrs_decode_assert(&hdrs, oh, ntohs(oh->length));
+ return (const uint8_t *) oh + ofphdrs_len(&hdrs);
+}
+\f
+/* Initializes 'replies' as a new list of stats messages that reply to
+ * 'request', which must be a stats request message. Initially the list will
+ * consist of only a single reply part without any body. The caller should
+ * use calls to the other ofpmp_*() functions to add to the body and split the
+ * message into multiple parts, if necessary. */
+void
+ofpmp_init(struct list *replies, const struct ofp_header *request)
+{
+ struct ofpbuf *msg;
+
+ list_init(replies);
+
+ msg = ofpraw_alloc_stats_reply(request, 1000);
+ list_push_back(replies, &msg->list_node);
+}
+
+/* Prepares to append up to 'len' bytes to the series of statistics replies in
+ * 'replies', which should have been initialized with ofpmp_init(), if
+ * necessary adding a new reply to the list.
+ *
+ * Returns an ofpbuf with at least 'len' bytes of tailroom. The 'len' bytes
+ * have not actually been allocated, so the caller must do so with
+ * e.g. ofpbuf_put_uninit(). */
+struct ofpbuf *
+ofpmp_reserve(struct list *replies, size_t len)
+{
+ struct ofpbuf *msg = ofpbuf_from_list(list_back(replies));
+
+ if (msg->size + len <= UINT16_MAX) {
+ ofpbuf_prealloc_tailroom(msg, len);
+ return msg;
+ } else {
+ unsigned int hdrs_len;
+ struct ofpbuf *next;
+ struct ofphdrs hdrs;
+
+ ofphdrs_decode_assert(&hdrs, msg->data, msg->size);
+ hdrs_len = ofphdrs_len(&hdrs);
+
+ next = ofpbuf_new(MAX(1024, hdrs_len + len));
+ ofpbuf_put(next, msg->data, hdrs_len);
+ list_push_back(replies, &next->list_node);
+
+ return next;
+ }
+}
+
+/* Appends 'len' bytes to the series of statistics replies in 'replies', and
+ * returns the first byte. */
+void *
+ofpmp_append(struct list *replies, size_t len)
+{
+ return ofpbuf_put_uninit(ofpmp_reserve(replies, len), len);
+}
+
+/* Sometimes, when composing stats replies, it's difficult to predict how long
+ * an individual reply chunk will be before actually encoding it into the reply
+ * buffer. This function allows easy handling of this case: just encode the
+ * reply, then use this function to break the message into two pieces if it
+ * exceeds the OpenFlow message limit.
+ *
+ * In detail, if the final stats message in 'replies' is too long for OpenFlow,
+ * this function breaks it into two separate stats replies, the first one with
+ * the first 'start_ofs' bytes, the second one containing the bytes from that
+ * offset onward. */
+void
+ofpmp_postappend(struct list *replies, size_t start_ofs)
+{
+ struct ofpbuf *msg = ofpbuf_from_list(list_back(replies));
+
+ assert(start_ofs <= UINT16_MAX);
+ if (msg->size > UINT16_MAX) {
+ size_t len = msg->size - start_ofs;
+ memcpy(ofpmp_append(replies, len),
+ (const uint8_t *) msg->data + start_ofs, len);
+ msg->size = start_ofs;
+ }
+}
+
+static ovs_be16 *
+ofpmp_flags__(const struct ofp_header *oh)
+{
+ return (oh->version == OFP10_VERSION
+ ? &((struct ofp_stats_msg *) oh)->flags
+ : &((struct ofp11_stats_msg *) oh)->flags);
+}
+
+/* Returns the OFPSF_* flags found in the OpenFlow stats header of 'oh', which
+ * must be an OpenFlow stats request or reply.
+ *
+ * (OFPSF_REPLY_MORE is the only defined flag.) */
+uint16_t
+ofpmp_flags(const struct ofp_header *oh)
+{
+ return ntohs(*ofpmp_flags__(oh));
+}
+
+/* Returns true if the OFPSF_REPLY_MORE flag is set in the OpenFlow stats
+ * header of 'oh', which must be an OpenFlow stats request or reply, false if
+ * it is not set. */
+bool
+ofpmp_more(const struct ofp_header *oh)
+{
+ return (ofpmp_flags(oh) & OFPSF_REPLY_MORE) != 0;
+}
+\f
+static void ofpmsgs_init(void);
+
+static const struct raw_info *
+raw_info_get(enum ofpraw raw)
+{
+ ofpmsgs_init();
+
+ assert(raw < ARRAY_SIZE(raw_infos));
+ return &raw_infos[raw];
+}
+
+static struct raw_instance *
+raw_instance_get(const struct raw_info *info, uint8_t version)
+{
+ assert(version >= info->min_version && version <= info->max_version);
+ return &info->instances[version - info->min_version];
+}
+
+static enum ofperr
+ofpraw_from_ofphdrs(enum ofpraw *raw, const struct ofphdrs *hdrs)
+{
+ static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 1);
+
+ struct raw_instance *raw_hdrs;
+ uint32_t hash;
+
+ ofpmsgs_init();
+
+ hash = ofphdrs_hash(hdrs);
+ HMAP_FOR_EACH_WITH_HASH (raw_hdrs, hmap_node, hash, &raw_instance_map) {
+ if (ofphdrs_equal(hdrs, &raw_hdrs->hdrs)) {
+ *raw = raw_hdrs->raw;
+ return 0;
+ }
+ }
+
+ if (!VLOG_DROP_WARN(&rl)) {
+ struct ds s;
+
+ ds_init(&s);
+ ds_put_format(&s, "version %"PRIu8", type %"PRIu8,
+ hdrs->version, hdrs->type);
+ if (ofphdrs_is_stat(hdrs)) {
+ ds_put_format(&s, ", stat %"PRIu16, hdrs->stat);
+ }
+ if (hdrs->vendor) {
+ ds_put_format(&s, ", vendor 0x%"PRIx32", subtype %"PRIu32,
+ hdrs->vendor, hdrs->subtype);
+ }
+ VLOG_WARN("unknown OpenFlow message (%s)", ds_cstr(&s));
+ ds_destroy(&s);
+ }
+
+ return (hdrs->vendor ? OFPERR_OFPBRC_BAD_SUBTYPE
+ : ofphdrs_is_stat(hdrs) ? OFPERR_OFPBRC_BAD_STAT
+ : OFPERR_OFPBRC_BAD_TYPE);
+}
+
+static void
+ofpmsgs_init(void)
+{
+ const struct raw_info *info;
+
+ if (raw_instance_map.buckets) {
+ return;
+ }
+
+ hmap_init(&raw_instance_map);
+ for (info = raw_infos; info < &raw_infos[ARRAY_SIZE(raw_infos)]; info++)
+ {
+ int n_instances = info->max_version - info->min_version + 1;
+ struct raw_instance *inst;
+
+ for (inst = info->instances;
+ inst < &info->instances[n_instances];
+ inst++) {
+ inst->hdrs_len = ofphdrs_len(&inst->hdrs);
+ hmap_insert(&raw_instance_map, &inst->hmap_node,
+ ofphdrs_hash(&inst->hdrs));
+ }
+ }
+}