/* * Copyright (c) 2017 Cisco and/or its affiliates. * 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. */ #ifndef PLUGINS_IOAM_PLUGIN_IOAM_UDP_PING_UDP_PING_PACKET_H_ #define PLUGINS_IOAM_PLUGIN_IOAM_UDP_PING_UDP_PING_PACKET_H_ #include <vppinfra/clib.h> #include <vnet/ip/ip6_hop_by_hop_packet.h> #include <vnet/udp/udp_packet.h> #define UDP_PING_PROBE 1 #define UDP_PING_REPLY 2 #define UDP_PING_PROBE_MARKER1 0xDEAD #define UDP_PING_PROBE_MARKER2 0xBEEF /* * Refer to: * https://tools.ietf.org/html/draft-lapukhov-dataplane-probe-01 * 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Probe Marker (1) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Probe Marker (2) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Version | Message Type | Flags | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Telemetry Request Vector | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Hop Limit | Hop Count | Must Be Zero | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Maximum Length | Current Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Sender's Handle | Sequence Number | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * * (1) The "Probe Marker" fields are arbitrary 32-bit values generally used by the network elements to identify the packet as a probe packet. These fields should be interpreted as unsigned integer values, stored in network byte order. For example, a network element may be configured to recognize a UDP packet destined to port 31337 and having 0xDEAD 0xBEEF as the values in "Probe Marker" field as an active probe, and treat it respectively. (2) "Version Number" is currently set to 1. (3) The "Message Type" field value could be either "1" - "Probe" or "2" - "Probe Reply" (4) The "Flags" field is 8 bits, and defines the following flags: (5) (1) "Overflow" (O-bit) (least significant bit). This bit is set by the network element if the number of records on the packet is at the maximum limit as specified by the packet: i.e. the packet is already "full" of telemetry information. (6) "Telemetry Request Vector" is a 32-bit long field that requests well-known inband telemetry information from the network elements on the path. A bit set in this vector translates to a request of a particular type of information. The following types/bits are currently defined, starting with the least significant bit first: (1) Bit 0: Device identifier. (2) Bit 1: Timestamp. (3) Bit 2: Queueing delay. (4) Bit 3: Ingress/Egress port identifiers. (5) Bit 31: Opaque state snapshot request. (7) "Hop Limit" is defined only for "Message Type" of "1" ("Probe"). For "Probe Reply" the "Hop Limit" field must be set to zero. This field is treated as an integer value representing the number of network elements. See the Section 4 section on the intended use of the field. (8) The "Hop Count" field specifies the current number of hops of capable network elements the packet has transit through. It begins with zero and must be incremented by one for every network element that adds a telemetry record. Combined with a push mechanism, this simplifies the work for the subsequent network element and the packet receiver. The subsequent network element just needs to parse the template and then insert new record(s) immediately after the template. (9) The "Max Length" field specifies the maximum length of the telemetry payload in bytes. Given that the sender knows the minimum path MTU, the sender can set the maximum of payload bytes allowed before exceeding the MTU. Thus, a simple comparison between "Current Length" and "Max Length" allows to decide whether or not data could be added. (10) The "Current Length" field specifies the current length of data stored in the probe. This field is incremented by eacn network element by the number of bytes it has added with the telemetry data frame. (11) The "Sender's Handle" field is set by the sender to allow the receiver to identify a particular originator of probe packets. Along with "Sequence Number" it allows for tracking of packet order and loss within the network. * */ typedef struct { u32 probe_marker1; u32 probe_marker2; u8 version; u8 msg_type; u16 flags; u32 tel_req_vec; u8 hop_limit; u8 hop_count; u16 reserve; u16 max_len; u16 cur_len; u16 sender_handle; u16 seq_no; } udp_ping_data; typedef struct { udp_header_t udp; udp_ping_data ping_data; } udp_ping_t; #endif /* PLUGINS_IOAM_PLUGIN_IOAM_UDP_PING_UDP_PING_PACKET_H_ */ /* * fd.io coding-style-patch-verification: ON * * Local Variables: * eval: (c-set-style "gnu") * End: */