Internet DRAFT - draft-marx-qlog-event-definitions-quic-h3
draft-marx-qlog-event-definitions-quic-h3
QUIC R. Marx
Internet-Draft Hasselt University
Intended status: Standards Track 2 November 2020
Expires: 6 May 2021
QUIC and HTTP/3 event definitions for qlog
draft-marx-qlog-event-definitions-quic-h3-02
Abstract
This document describes concrete qlog event definitions and their
metadata for QUIC and HTTP/3-related events. These events can then
be embedded in the higher level schema defined in [QLOG-MAIN].
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
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This Internet-Draft will expire on 6 May 2021.
Copyright Notice
Copyright (c) 2020 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents (https://trustee.ietf.org/
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Please review these documents carefully, as they describe your rights
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 5
1.1. Notational Conventions . . . . . . . . . . . . . . . . . 5
2. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.1. Importance . . . . . . . . . . . . . . . . . . . . . . . 6
2.2. Custom fields . . . . . . . . . . . . . . . . . . . . . . 7
3. Events not belonging to a single connection . . . . . . . . . 7
4. QUIC and HTTP/3 fields . . . . . . . . . . . . . . . . . . . 8
4.1. Raw packet and frame information . . . . . . . . . . . . 8
5. QUIC event definitions . . . . . . . . . . . . . . . . . . . 10
5.1. connectivity . . . . . . . . . . . . . . . . . . . . . . 10
5.1.1. server_listening . . . . . . . . . . . . . . . . . . 10
5.1.2. connection_started . . . . . . . . . . . . . . . . . 10
5.1.3. connection_closed . . . . . . . . . . . . . . . . . . 11
5.1.4. connection_id_updated . . . . . . . . . . . . . . . . 12
5.1.5. spin_bit_updated . . . . . . . . . . . . . . . . . . 12
5.1.6. connection_retried . . . . . . . . . . . . . . . . . 12
5.1.7. connection_state_updated . . . . . . . . . . . . . . 13
5.1.8. MIGRATION-related events . . . . . . . . . . . . . . 15
5.2. security . . . . . . . . . . . . . . . . . . . . . . . . 15
5.2.1. key_updated . . . . . . . . . . . . . . . . . . . . . 15
5.2.2. key_retired . . . . . . . . . . . . . . . . . . . . . 15
5.3. transport . . . . . . . . . . . . . . . . . . . . . . . . 16
5.3.1. version_information . . . . . . . . . . . . . . . . . 16
5.3.2. alpn_information . . . . . . . . . . . . . . . . . . 17
5.3.3. parameters_set . . . . . . . . . . . . . . . . . . . 18
5.3.4. parameters_restored . . . . . . . . . . . . . . . . . 20
5.3.5. packet_sent . . . . . . . . . . . . . . . . . . . . . 20
5.3.6. packet_received . . . . . . . . . . . . . . . . . . . 21
5.3.7. packet_dropped . . . . . . . . . . . . . . . . . . . 22
5.3.8. packet_buffered . . . . . . . . . . . . . . . . . . . 23
5.3.9. packets_acked . . . . . . . . . . . . . . . . . . . . 24
5.3.10. datagrams_sent . . . . . . . . . . . . . . . . . . . 24
5.3.11. datagrams_received . . . . . . . . . . . . . . . . . 25
5.3.12. datagram_dropped . . . . . . . . . . . . . . . . . . 25
5.3.13. stream_state_updated . . . . . . . . . . . . . . . . 26
5.3.14. frames_processed . . . . . . . . . . . . . . . . . . 27
5.3.15. data_moved . . . . . . . . . . . . . . . . . . . . . 28
5.4. recovery . . . . . . . . . . . . . . . . . . . . . . . . 30
5.4.1. parameters_set . . . . . . . . . . . . . . . . . . . 30
5.4.2. metrics_updated . . . . . . . . . . . . . . . . . . . 30
5.4.3. congestion_state_updated . . . . . . . . . . . . . . 31
5.4.4. loss_timer_updated . . . . . . . . . . . . . . . . . 32
5.4.5. packet_lost . . . . . . . . . . . . . . . . . . . . . 33
5.4.6. marked_for_retransmit . . . . . . . . . . . . . . . . 34
6. HTTP/3 event definitions . . . . . . . . . . . . . . . . . . 34
6.1. http . . . . . . . . . . . . . . . . . . . . . . . . . . 34
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6.1.1. parameters_set . . . . . . . . . . . . . . . . . . . 34
6.1.2. parameters_restored . . . . . . . . . . . . . . . . . 35
6.1.3. stream_type_set . . . . . . . . . . . . . . . . . . . 36
6.1.4. frame_created . . . . . . . . . . . . . . . . . . . . 36
6.1.5. frame_parsed . . . . . . . . . . . . . . . . . . . . 37
6.1.6. push_resolved . . . . . . . . . . . . . . . . . . . . 37
6.2. qpack . . . . . . . . . . . . . . . . . . . . . . . . . . 38
6.2.1. state_updated . . . . . . . . . . . . . . . . . . . . 38
6.2.2. stream_state_updated . . . . . . . . . . . . . . . . 39
6.2.3. dynamic_table_updated . . . . . . . . . . . . . . . . 39
6.2.4. headers_encoded . . . . . . . . . . . . . . . . . . . 39
6.2.5. headers_decoded . . . . . . . . . . . . . . . . . . . 40
6.2.6. instruction_created . . . . . . . . . . . . . . . . . 40
6.2.7. instruction_parsed . . . . . . . . . . . . . . . . . 41
7. Generic events and Simulation indicators . . . . . . . . . . 41
7.1. generic . . . . . . . . . . . . . . . . . . . . . . . . . 41
7.1.1. error . . . . . . . . . . . . . . . . . . . . . . . . 42
7.1.2. warning . . . . . . . . . . . . . . . . . . . . . . . 42
7.1.3. info . . . . . . . . . . . . . . . . . . . . . . . . 42
7.1.4. debug . . . . . . . . . . . . . . . . . . . . . . . . 42
7.1.5. verbose . . . . . . . . . . . . . . . . . . . . . . . 43
7.2. simulation . . . . . . . . . . . . . . . . . . . . . . . 43
7.2.1. scenario . . . . . . . . . . . . . . . . . . . . . . 43
7.2.2. marker . . . . . . . . . . . . . . . . . . . . . . . 44
8. Security Considerations . . . . . . . . . . . . . . . . . . . 44
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 44
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 44
10.1. Normative References . . . . . . . . . . . . . . . . . . 44
10.2. Informative References . . . . . . . . . . . . . . . . . 45
Appendix A. QUIC data field definitions . . . . . . . . . . . . 45
A.1. IPAddress . . . . . . . . . . . . . . . . . . . . . . . . 45
A.2. PacketType . . . . . . . . . . . . . . . . . . . . . . . 45
A.3. PacketNumberSpace . . . . . . . . . . . . . . . . . . . . 45
A.4. PacketHeader . . . . . . . . . . . . . . . . . . . . . . 45
A.5. Token . . . . . . . . . . . . . . . . . . . . . . . . . . 46
A.6. KeyType . . . . . . . . . . . . . . . . . . . . . . . . . 46
A.7. QUIC Frames . . . . . . . . . . . . . . . . . . . . . . . 47
A.7.1. PaddingFrame . . . . . . . . . . . . . . . . . . . . 47
A.7.2. PingFrame . . . . . . . . . . . . . . . . . . . . . . 47
A.7.3. AckFrame . . . . . . . . . . . . . . . . . . . . . . 47
A.7.4. ResetStreamFrame . . . . . . . . . . . . . . . . . . 48
A.7.5. StopSendingFrame . . . . . . . . . . . . . . . . . . 48
A.7.6. CryptoFrame . . . . . . . . . . . . . . . . . . . . . 49
A.7.7. NewTokenFrame . . . . . . . . . . . . . . . . . . . . 49
A.7.8. StreamFrame . . . . . . . . . . . . . . . . . . . . . 49
A.7.9. MaxDataFrame . . . . . . . . . . . . . . . . . . . . 50
A.7.10. MaxStreamDataFrame . . . . . . . . . . . . . . . . . 50
A.7.11. MaxStreamsFrame . . . . . . . . . . . . . . . . . . . 50
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A.7.12. DataBlockedFrame . . . . . . . . . . . . . . . . . . 50
A.7.13. StreamDataBlockedFrame . . . . . . . . . . . . . . . 50
A.7.14. StreamsBlockedFrame . . . . . . . . . . . . . . . . . 50
A.7.15. NewConnectionIDFrame . . . . . . . . . . . . . . . . 51
A.7.16. RetireConnectionIDFrame . . . . . . . . . . . . . . . 51
A.7.17. PathChallengeFrame . . . . . . . . . . . . . . . . . 51
A.7.18. PathResponseFrame . . . . . . . . . . . . . . . . . . 51
A.7.19. ConnectionCloseFrame . . . . . . . . . . . . . . . . 52
A.7.20. HandshakeDoneFrame . . . . . . . . . . . . . . . . . 52
A.7.21. UnknownFrame . . . . . . . . . . . . . . . . . . . . 52
A.7.22. TransportError . . . . . . . . . . . . . . . . . . . 52
A.7.23. CryptoError . . . . . . . . . . . . . . . . . . . . . 53
Appendix B. HTTP/3 data field definitions . . . . . . . . . . . 53
B.1. HTTP/3 Frames . . . . . . . . . . . . . . . . . . . . . . 53
B.1.1. DataFrame . . . . . . . . . . . . . . . . . . . . . . 53
B.1.2. HeadersFrame . . . . . . . . . . . . . . . . . . . . 54
B.1.3. CancelPushFrame . . . . . . . . . . . . . . . . . . . 54
B.1.4. SettingsFrame . . . . . . . . . . . . . . . . . . . . 54
B.1.5. PushPromiseFrame . . . . . . . . . . . . . . . . . . 54
B.1.6. GoAwayFrame . . . . . . . . . . . . . . . . . . . . . 55
B.1.7. MaxPushIDFrame . . . . . . . . . . . . . . . . . . . 55
B.1.8. DuplicatePushFrame . . . . . . . . . . . . . . . . . 55
B.1.9. ReservedFrame . . . . . . . . . . . . . . . . . . . . 55
B.1.10. UnknownFrame . . . . . . . . . . . . . . . . . . . . 55
B.2. ApplicationError . . . . . . . . . . . . . . . . . . . . 55
Appendix C. QPACK DATA type definitions . . . . . . . . . . . . 56
C.1. QPACK Instructions . . . . . . . . . . . . . . . . . . . 56
C.1.1. SetDynamicTableCapacityInstruction . . . . . . . . . 56
C.1.2. InsertWithNameReferenceInstruction . . . . . . . . . 56
C.1.3. InsertWithoutNameReferenceInstruction . . . . . . . . 57
C.1.4. DuplicateInstruction . . . . . . . . . . . . . . . . 57
C.1.5. HeaderAcknowledgementInstruction . . . . . . . . . . 57
C.1.6. StreamCancellationInstruction . . . . . . . . . . . . 57
C.1.7. InsertCountIncrementInstruction . . . . . . . . . . . 58
C.2. QPACK Header compression . . . . . . . . . . . . . . . . 58
C.2.1. IndexedHeaderField . . . . . . . . . . . . . . . . . 58
C.2.2. LiteralHeaderFieldWithName . . . . . . . . . . . . . 58
C.2.3. LiteralHeaderFieldWithoutName . . . . . . . . . . . . 59
C.2.4. QPackHeaderBlockPrefix . . . . . . . . . . . . . . . 59
Appendix D. Change Log . . . . . . . . . . . . . . . . . . . . . 59
D.1. Since draft-01: . . . . . . . . . . . . . . . . . . . . . 59
D.2. Since draft-00: . . . . . . . . . . . . . . . . . . . . . 61
Appendix E. Design Variations . . . . . . . . . . . . . . . . . 61
Appendix F. Acknowledgements . . . . . . . . . . . . . . . . . . 61
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 61
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1. Introduction
This document describes the values of the qlog name ("category" +
"event") and "data" fields and their semantics for the QUIC and
HTTP/3 protocols. This document is based on draft-29 of the QUIC and
HTTP/3 I-Ds QUIC-TRANSPORT [QUIC-HTTP] and draft-16 of the QPACK I-D
[QUIC-QPACK].
Feedback and discussion welcome at https://github.com/quiclog/
internet-drafts (https://github.com/quiclog/internet-drafts).
Readers are advised to refer to the "editor's draft" at that URL for
an up-to-date version of this document.
Concrete examples of integrations of this schema in various
programming languages can be found at https://github.com/quiclog/
qlog/ (https://github.com/quiclog/qlog/).
1.1. Notational Conventions
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119].
The examples and data definitions in ths document are expressed in a
custom data definition language, inspired by JSON and TypeScript, and
described in [QLOG-MAIN].
2. Overview
This document describes the values of the qlog "name" ("category" +
"event") and "data" fields and their semantics for the QUIC and
HTTP/3 protocols.
This document assumes the usage of the encompassing main qlog schema
defined in [QLOG-MAIN]. Each subsection below defines a separate
category (for example connectivity, transport, http) and each
subsubsection is an event type (for example "packet_received").
For each event type, its importance and data definition is laid out,
often accompanied by possible values for the optional "trigger"
field. For the definition and semantics of "trigger", see the main
schema document.
Most of the complex datastructures, enums and re-usable definitions
are grouped together on the bottom of this document for clarity.
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2.1. Importance
Many of the events defined in this document map directly to concepts
seen in the QUIC and HTTP/3 documents, while others act as
aggregating events that combine data from several possible protocol
behaviours or code paths into one. This is done to reduce the amount
of unique event definitions, as reflecting each possible protocol
event as a separate qlog entity would cause an explosion of event
types. Similarly, we prevent logging duplicate packet data as much
as possible. As such, especially packet header value updates are
split out into separate events (for example spin_bit_updated,
connection_id_updated), as they are expected to change sparingly.
Consequently, many events that can be directly inferred from data on
the wire (for example flow control limit changes) if the
implementation is bug-free, are currently not explicitly defined as
stand-alone events. Exceptions can be made for common events that
benefit from being easily identifiable or individually logged (for
example the "packets_acked" event). This can in turn give rise to
separate events logging similar data, where it is not always clear
which event should be logged (for example the separate
"connection_started" event, whereas the more general
"connection_state_updated" event also allows indicating that a
connection was started).
To aid in this decision making, each event has an "importance
indicator" with one of three values, in decreasing order of
importance and exptected usage:
* Core
* Base
* Extra
The "Core" events are the events that SHOULD be present in all qlog
files. These are mostly tied to basic packet and frame parsing and
creation, as well as listing basic internal metrics. Tool
implementers SHOULD expect and add support for these events, though
SHOULD NOT expect all Core events to be present in each qlog trace.
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The "Base" events add additional debugging options and CAN be present
in qlog files. Most of these can be implicitly inferred from data in
Core events (if those contain all their properties), but for many it
is better to log the events explicitly as well, making it clearer how
the implementation behaves. These events are for example tied to
passing data around in buffers, to how internal state machines change
and help show when decisions are actually made based on received
data. Tool implementers SHOULD at least add support for showing the
contents of these events, if they do not handle them explicitly.
The "Extra" events are considered mostly useful for low-level
debugging of the implementation, rather than the protocol. They
allow more fine-grained tracking of internal behaviour. As such,
they CAN be present in qlog files and tool implementers CAN add
support for these, but they are not required to.
Note that in some cases, implementers might not want to log for
example frame-level details in the "Core" events due to performance
or privacy considerations. In this case, they SHOULD use (a subset
of) relevant "Base" events instead to ensure usability of the qlog
output. As an example, implementations that do not log
"packet_received" events and thus also not which (if any) ACK frames
the packet contain, SHOULD log "packets_acked" events instead.
Finally, for event types who's data (partially) overlap with other
event types' definitions, where necessary this document includes
guidance on which to use in specific situations.
2.2. Custom fields
Note that implementers are free to define new category and event
types, as well as values for the "trigger" property within the "data"
field, or other member fields of the "data" field, as they see fit.
They SHOULD NOT however expect non-specialized tools to recognize or
visualize this custom data. However, tools SHOULD make an effort to
visualize even unknown data if possible in the specific tool's
context.
3. Events not belonging to a single connection
For several types of events, it is sometimes impossible to tie them
to a specific conceptual QUIC connection (e.g., a packet_dropped
event triggered because the packet has an unknown connection_id in
the header). Since qlog events in a trace are typically associated
with a single connection, it is unclear how to log these events.
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Ideally, implementers SHOULD create a separate, individual "endpoint-
level" trace file (or group_id value), not associated with a specific
connection (for example a "server.qlog" or group_id = "client"), and
log all events that do not belong to a single connection to this
grouping trace. However, this is not always practical, depending on
the implementation. Because the semantics of most of these events
are well-defined in the protocols and because they are difficult to
mis-interpret as belonging to a connection, implementers MAY choose
to log events not belonging to a particular connection in any other
trace, even those strongly associated with a single connection.
Note that this can make it difficult to match logs from different
vantage points with each other. For example, from the client side,
it is easy to log connections with version negotiation or retry in
the same trace, while on the server they would most likely be logged
in separate traces. Servers can take extra efforts (and keep
additional state) to keep these events combined in a single trace
however (for example by also matching connections on their four-tuple
instead of just the connection ID).
4. QUIC and HTTP/3 fields
This document re-uses all the fields defined in the main qlog schema
(e.g., name, category, type, data, group_id, protocol_type, the time-
related fields, etc.).
The value of the "protocol_type" qlog field MUST be "QUIC_HTTP3".
When the qlog "group_id" field is used, it is recommended to use
QUIC's Original Destination Connection ID (ODCID, the CID chosen by
the client when first contacting the server), as this is the only
value that does not change over the course of the connection and can
be used to link more advanced QUIC packets (e.g., Retry, Version
Negotiation) to a given connection. Similarly, the ODCID should be
used as the qlog filename or file identifier, potentially suffixed by
the vantagepoint type (For example, abcd1234_server.qlog would
contain the server-side trace of the connection with ODCID abcd1234).
4.1. Raw packet and frame information
While qlog is a more high-level logging format, it also allows the
inclusion of most raw wire image information, such as byte lengths
and even raw byte values. This can be useful when for example
investigating or tuning packetization behaviour or determining
encoding/framing overheads. However, these fields are not always
necessary and can take up considerable space if logged for each
packet or frame. As such, they are grouped in a separate optional
field called "raw" of type RawInfo (where applicable).
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class RawInfo {
length?:uint64; // full packet/frame length, including header and AEAD authentication tag lengths (where applicable)
payload_length?:uint64; // length of the packet/frame payload, excluding AEAD tag. For many control frames, this will have a value of zero
data?:bytes; // full packet/frame contents, including header and AEAD authentication tag (where applicable)
}
Note: QUIC packets always include an AEAD authentication tag at the
end. As this tag is always the same size for a given connection
(it depends on the used TLS cipher), we do not have a separate
"aead_tag_length" field here. Instead, this field is reflected in
"transport:parameters_set" and can be logged only once.
Note: There is intentionally no explicit header_length field in
RawInfo. QUIC and HTTP/3 use many Variable-Length Integer Encoded
(VLIE) values in their packet and frame headers, which are of a
dynamic length. Note too that because of this, we cannot
deterministally reconstruct the header encoding/length from qlog
data, as implementations might not necessarily employ the most
efficient VLIE scheme for all values. As such, it is typically
easier to log just the total packet/frame length and the payload
length. The header length can be calculated by tools as:
For QUIC packets: header_length = length - payload_length -
aead_tag_length
For QUIC and HTTP/3 frames: header_length = length -
payload_length
For UDP datagrams: header_length = length - payload_length
Note: In some cases, the length fields are also explicitly reflected
inside of frame/packet headers. For example, the QUIC STREAM
frame has a "length" field indicating its payload size.
Similarly, all HTTP/3 frames include their explicit payload
lengths in the frame header. Finally, the QUIC Long Header has a
"length" field which is equal to the payload length plus the
packet number length. In these cases, those fields are
intentionally preserved in the event definitions. Even though
this can lead to duplicate data when the full RawInfo is logged,
it allows a more direct mapping of the QUIC and HTTP/3
specifications to qlog, making it easier for users to interpret.
Note: as described in [QLOG-MAIN], the RawInfo:data field can be
truncated for privacy or security purposes (for example excluding
payload data). In this case, the length properties should still
indicate the non-truncated lengths.
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5. QUIC event definitions
Each subheading in this section is a qlog event category, while each
sub-subheading is a qlog event type. Concretely, for the following
two items, we have the category "connectivity" and event type
"server_listening", resulting in a concatenated qlog "name" field
value of "connectivity:server_listening".
5.1. connectivity
5.1.1. server_listening
Importance: Extra
Emitted when the server starts accepting connections.
Data:
{
ip_v4?: IPAddress,
ip_v6?: IPAddress,
port_v4?: uint32,
port_v6?: uint32,
retry_required?:boolean // the server will always answer client initials with a retry (no 1-RTT connection setups by choice)
}
Note: some QUIC stacks do not handle sockets directly and are thus
unable to log IP and/or port information.
5.1.2. connection_started
Importance: Base
Used for both attempting (client-perspective) and accepting (server-
perspective) new connections. Note that this event has overlap with
connection_state_updated and this is a separate event mainly because
of all the additional data that should be logged.
Data:
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{
ip_version?: "v4" | "v6",
src_ip?: IPAddress,
dst_ip?: IPAddress,
protocol?: string, // transport layer protocol (default "QUIC")
src_port?: uint32,
dst_port?: uint32,
src_cid?: bytes,
dst_cid?: bytes,
}
Note: some QUIC stacks do not handle sockets directly and are thus
unable to log IP and/or port information.
5.1.3. connection_closed
Importance: Base
Used for logging when a connection was closed, typically when an
error or timeout occurred. Note that this event has overlap with
connectivity:connection_state_updated, as well as the
CONNECTION_CLOSE frame. However, in practice, when analyzing large
deployments, it can be useful to have a single event representing a
connection_closed event, which also includes an additional reason
field to provide additional information. Additionally, it is useful
to log closures due to timeouts, which are difficult to reflect using
the other options.
In QUIC there are two main connection-closing error categories:
connection and application errors. They have well-defined error
codes and semantics. Next to these however, there can be internal
errors that occur that may or may not get mapped to the official
error codes in implementation-specific ways. As such, multiple error
codes can be set on the same event to reflect this.
{
owner?:"local"|"remote", // which side closed the connection
connection_code?:TransportError | CryptoError | uint32,
application_code?:ApplicationError | uint32,
internal_code?:uint32,
reason?:string
}
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Triggers: * clean * handshake_timeout * idle_timeout * error // this
is called the "immediate close" in the QUIC specification *
stateless_reset * version_mismatch * application // for example
HTTP/3's GOAWAY frame
5.1.4. connection_id_updated
Importance: Base
This event is emitted when either party updates their current
Connection ID. As this typically happens only sparingly over the
course of a connection, this event allows loggers to be more
efficient than logging the observed CID with each packet in the
.header field of the "packet_sent" or "packet_received" events.
This is viewed from the perspective of the one applying the new id.
As such, if we receive a new connection id from our peer, we will see
the dst_ fields are set. If we update our own connection id (e.g.,
NEW_CONNECTION_ID frame), we log the src_ fields.
Data:
{
owner: "local" | "remote",
old?:bytes,
new?:bytes,
}
5.1.5. spin_bit_updated
Importance: Base
To be emitted when the spin bit changes value. It SHOULD NOT be
emitted if the spin bit is set without changing its value.
Data:
{
state: boolean
}
5.1.6. connection_retried
TODO
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5.1.7. connection_state_updated
Importance: Base
This event is used to track progress through QUIC's complex handshake
and connection close procedures. It is intended to provide
exhaustive options to log each state individually, but also provides
a more basic, simpler set for implementations less interested in
tracking each smaller state transition. As such, users should not
expect to see -all- these states reflected in all qlogs and
implementers should focus on support for the SimpleConnectionState
set.
Data: ~~~ { old?: ConnectionState | SimpleConnectionState, new:
ConnectionState | SimpleConnectionState }
enum ConnectionState { attempted, // initial sent/received
peer_validated, // peer address validated by: client sent Handshake
packet OR client used CONNID chosen by the server. transport-draft-
32, section-8.1 handshake_started, early_write, // 1 RTT can be sent,
but handshake isn't done yet handshake_complete, // TLS handshake
complete: Finished received and sent. tls-draft-32, section-4.1.1
handshake_confirmed, // HANDSHAKE_DONE sent/received (connection is
now "active", 1RTT can be sent). tls-draft-32, section-4.1.2 closing,
draining, // connection_close sent/received closed // draining period
done, connection state discarded }
enum SimpleConnectionState { attempted, handshake_started,
handshake_confirmed, closed } ~~~
These states correspond to the following transitions for both client
and server:
*Client:*
* send initial
- state = attempted
* get initial
- state = validated _(not really "needed" at the client, but
somewhat useful to indicate progress nonetheless)_
* get first Handshake packet
- state = handshake_started
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* get Handshake packet containing ServerFinished
- state = handshake_complete
* send ClientFinished
- state = early_write (1RTT can now be sent)
* get HANDSHAKE_DONE
- state = handshake_confirmed
*Server:*
* get initial
- state = attempted
* send initial _(don't think this needs a separate state, since some
handshake will always be sent in the same flight as this?)_
* send handshake EE, CERT, CV, ...
- state = handshake_started
* send ServerFinished
- state = early_write (1RTT can now be sent)
* get first handshake packet / something using a server-issued CID
of min length
- state = validated
* get handshake packet containing ClientFinished
- state = handshake_complete
* send HANDSHAKE_DONE
- state = handshake_confirmed
Note: connection_state_changed with a new state of "attempted" is
the same conceptual event as the connection_started event above
from the client's perspective. Similarly, a state of "closing" or
"draining" corresponds to the connection_closed event.
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5.1.8. MIGRATION-related events
e.g., path_updated
TODO: read up on the draft how migration works and whether to best
fit this here or in TRANSPORT TODO: integrate
https://tools.ietf.org/html/draft-deconinck-quic-multipath-02
For now, infer from other connectivity events and path_challenge/
path_response frames
5.2. security
5.2.1. key_updated
Importance: Base
Note: secret_updated would be more correct, but in the draft it's
called KEY_UPDATE, so stick with that for consistency
Data:
{
key_type:KeyType,
old?:bytes,
new:bytes,
generation?:uint32 // needed for 1RTT key updates
}
Triggers:
* "tls" // (e.g., initial, handshake and 0-RTT keys are generated by
TLS)
* "remote_update"
* "local_update"
5.2.2. key_retired
Importance: Base
Data:
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{
key_type:KeyType,
key?:bytes,
generation?:uint32 // needed for 1RTT key updates
}
Triggers:
* "tls" // (e.g., initial, handshake and 0-RTT keys are dropped
implicitly)
* "remote_update"
* "local_update"
5.3. transport
5.3.1. version_information
Importance: Core
QUIC endpoints each have their own list of of QUIC versions they
support. The client uses the most likely version in their first
initial. If the server does support that version, it replies with a
version_negotiation packet, containing supported versions. From
this, the client selects a version. This event aggregates all this
information in a single event type. It also allows logging of
supported versions at an endpoint without actual version negotiation
needing to happen.
Data:
{
server_versions?:Array<bytes>,
client_versions?:Array<bytes>,
chosen_version?:bytes
}
Intended use:
* When sending an initial, the client logs this event with
client_versions and chosen_version set
* Upon receiving a client initial with a supported version, the
server logs this event with server_versions and chosen_version set
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* Upon receiving a client initial with an unsupported version, the
server logs this event with server_versions set and
client_versions to the single-element array containing the
client's attempted version. The absence of chosen_version implies
no overlap was found.
* Upon receiving a version negotiation packet from the server, the
client logs this event with client_versions set and
server_versions to the versions in the version negotiation packet
and chosen_version to the version it will use for the next initial
packet
5.3.2. alpn_information
Importance: Core
QUIC implementations each have their own list of application level
protocols and versions thereof they support. The client includes a
list of their supported options in its first initial as part of the
TLS Application Layer Protocol Negotiation (alpn) extension. If
there are common option(s), the server chooses the most optimal one
and communicates this back to the client. If not, the connection is
closed.
Data:
{
server_alpns?:Array<string>,
client_alpns?:Array<string>,
chosen_alpn?:string
}
Intended use:
* When sending an initial, the client logs this event with
client_alpns set
* When receiving an initial with a supported alpn, the server logs
this event with server_alpns set, client_alpns equalling the
client-provided list, and chosen_alpn to the value it will send
back to the client.
* When receiving an initial with an alpn, the client logs this event
with chosen_alpn to the received value.
* Alternatively, a client can choose to not log the first event, but
wait for the receipt of the server initial to log this event with
both client_alpns and chosen_alpn set.
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5.3.3. parameters_set
Importance: Core
This event groups settings from several different sources (transport
parameters, TLS ciphers, etc.) into a single event. This is done to
minimize the amount of events and to decouple conceptual setting
impacts from their underlying mechanism for easier high-level
reasoning.
All these settings are typically set once and never change. However,
they are typically set at different times during the connection, so
there will typically be several instances of this event with
different fields set.
Note that some settings have two variations (one set locally, one
requested by the remote peer). This is reflected in the "owner"
field. As such, this field MUST be correct for all settings included
a single event instance. If you need to log settings from two sides,
you MUST emit two separate event instances.
In the case of connection resumption and 0-RTT, some of the server's
parameters are stored up-front at the client and used for the initial
connection startup. They are later updated with the server's reply.
In these cases, utilize the separate "parameters_restored" event to
indicate the initial values, and this event to indicate the updated
values, as normal.
Data:
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{
owner?:"local" | "remote",
resumption_allowed?:boolean, // valid session ticket was received
early_data_enabled?:boolean, // early data extension was enabled on the TLS layer
tls_cipher?:string, // (e.g., "AES_128_GCM_SHA256")
aead_tag_length?:uint8, // depends on the TLS cipher, but it's easier to be explicit. Default value is 16
// transport parameters from the TLS layer:
original_destination_connection_id?:bytes,
initial_source_connection_id?:bytes,
retry_source_connection_id?:bytes,
stateless_reset_token?:Token,
disable_active_migration?:boolean,
max_idle_timeout?:uint64,
max_udp_payload_size?:uint32,
ack_delay_exponent?:uint16,
max_ack_delay?:uint16,
active_connection_id_limit?:uint32,
initial_max_data?:uint64,
initial_max_stream_data_bidi_local?:uint64,
initial_max_stream_data_bidi_remote?:uint64,
initial_max_stream_data_uni?:uint64,
initial_max_streams_bidi?:uint64,
initial_max_streams_uni?:uint64,
preferred_address?:PreferredAddress
}
interface PreferredAddress {
ip_v4:IPAddress,
ip_v6:IPAddress,
port_v4:uint16,
port_v6:uint16,
connection_id:bytes,
stateless_reset_token:Token
}
Additionally, this event can contain any number of unspecified
fields. This is to reflect setting of for example unknown (greased)
transport parameters or employed (proprietary) extensions.
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5.3.4. parameters_restored
Importance: Base
When using QUIC 0-RTT, clients are expected to remember and restore
the server's transport parameters from the previous connection. This
event is used to indicate which parameters were restored and to which
values when utilizing 0-RTT. Note that not all transport parameters
should be restored (many are even prohibited from being re-utilized).
The ones listed here are the ones expected to be useful for correct
0-RTT usage.
Data:
{
disable_active_migration?:boolean,
max_idle_timeout?:uint64,
max_udp_payload_size?:uint32,
active_connection_id_limit?:uint32,
initial_max_data?:uint64,
initial_max_stream_data_bidi_local?:uint64,
initial_max_stream_data_bidi_remote?:uint64,
initial_max_stream_data_uni?:uint64,
initial_max_streams_bidi?:uint64,
initial_max_streams_uni?:uint64,
}
Note that, like parameters_set above, this event can contain any
number of unspecified fields to allow for additional/custom
parameters.
5.3.5. packet_sent
Importance: Core
Data:
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{
header:PacketHeader,
frames?:Array<QuicFrame>, // see appendix for the definitions
is_coalesced?:boolean, // default value is false
retry_token?:Token, // only if header.packet_type === retry
stateless_reset_token?:bytes, // only if header.packet_type === stateless_reset. Is always 128 bits in length.
supported_versions:Array<bytes>, // only if header.packet_type === version_negotiation
raw?:RawInfo,
datagram_id?:uint32
}
Note: We do not explicitly log the encryption_level or
packet_number_space: the header.packet_type specifies this by
inference (assuming correct implementation)
Triggers:
* "retransmit_reordered" // draft-23 5.1.1
* "retransmit_timeout" // draft-23 5.1.2
* "pto_probe" // draft-23 5.3.1
* "retransmit_crypto" // draft-19 6.2
* "cc_bandwidth_probe" // needed for some CCs to figure out
bandwidth allocations when there are no normal sends
Note: for more details on "datagram_id", see Section 5.3.10. It is
only needed when keeping track of packet coalescing.
5.3.6. packet_received
Importance: Core
Data:
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{
header:PacketHeader,
frames?:Array<QuicFrame>, // see appendix for the definitions
is_coalesced?:boolean,
retry_token?:Token, // only if header.packet_type === retry
stateless_reset_token?:bytes, // only if header.packet_type === stateless_reset. Is always 128 bits in length.
supported_versions:Array<bytes>, // only if header.packet_type === version_negotiation
raw?:RawInfo,
datagram_id?:uint32
}
Note: We do not explicitly log the encryption_level or
packet_number_space: the header.packet_type specifies this by
inference (assuming correct implementation)
Triggers:
* "keys_available" // if packet was buffered because it couldn't be
decrypted before
Note: for more details on "datagram_id", see Section 5.3.10. It is
only needed when keeping track of packet coalescing.
5.3.7. packet_dropped
Importance: Base
This event indicates a QUIC-level packet was dropped after partial or
no parsing.
Data:
{
header?:PacketHeader, // primarily packet_type should be filled here, as other fields might not be parseable
raw?:RawInfo,
datagram_id?:uint32
}
For this event, the "trigger" field SHOULD be set (for example to one
of the values below), as this helps tremendously in debugging.
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Triggers:
* "key_unavailable"
* "unknown_connection_id"
* "header_parse_error"
* "payload_decrypt_error"
* "protocol_violation"
* "dos_prevention"
* "unsupported_version"
* "unexpected_packet"
* "unexpected_source_connection_id"
* "unexpected_version"
* "duplicate"
* "invalid_initial"
Note: sometimes packets are dropped before they can be associated
with a particular connection (e.g., in case of
"unsupported_version"). This situation is discussed more in
Section 3.
Note: for more details on "datagram_id", see Section 5.3.10. It is
only needed when keeping track of packet coalescing.
5.3.8. packet_buffered
Importance: Base
This event is emitted when a packet is buffered because it cannot be
processed yet. Typically, this is because the packet cannot be
parsed yet, and thus we only log the full packet contents when it was
parsed in a packet_received event.
Data:
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{
header?:PacketHeader, // primarily packet_type and possible packet_number should be filled here, as other elements might not be available yet
raw?:RawInfo,
datagram_id?:uint32
}
Note: for more details on "datagram_id", see Section 5.3.10. It is
only needed when keeping track of packet coalescing.
Triggers:
* "backpressure" // indicates the parser cannot keep up, temporarily
buffers packet for later processing
* "keys_unavailable" // if packet cannot be decrypted because the
proper keys were not yet available
5.3.9. packets_acked
Importance: Extra
This event is emitted when a (group of) sent packet(s) is
acknowledged by the remote peer _for the first time_. This
information could also be deduced from the contents of received ACK
frames. However, ACK frames require additional processing logic to
determine when a given packet is acknowledged for the first time, as
QUIC uses ACK ranges which can include repeated ACKs. Additionally,
this event can be used by implementations that do not log frame
contents.
Data: ~~~ { packet_number_space?:PacketNumberSpace,
packet_numbers?:Array<uint64> } ~~~
Note: if packet_number_space is omitted, it assumes the default value
of PacketNumberSpace.application_data, as this is by far the most
prevalent packet number space a typical QUIC connection will use.
5.3.10. datagrams_sent
Importance: Extra
When we pass one or more UDP-level datagrams to the socket. This is
useful for determining how QUIC packet buffers are drained to the OS.
Data:
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{
count?:uint16, // to support passing multiple at once
raw?:Array<RawInfo>, // RawInfo:length field indicates total length of the datagrams, including UDP header length
datagram_ids?:Array<uint32>
}
Note: QUIC itself does not have a concept of a "datagram_id". This
field is a purely qlog-specific construct to allow tracking how
multiple QUIC packets are coalesced inside of a single UDP datagram,
which is an important optimization during the QUIC handshake. For
this, implementations assign a (per-endpoint) unique ID to each
datagram and keep track of which packets were coalesced into the same
datagram. As packet coalescing typically only happens during the
handshake (as it requires at least one long header packet), this can
be done without much overhead.
5.3.11. datagrams_received
Importance: Extra
When we receive one or more UDP-level datagrams from the socket.
This is useful for determining how datagrams are passed to the user
space stack from the OS.
Data:
{
count?:uint16, // to support passing multiple at once
raw?:Array<RawInfo>, // RawInfo:length field indicates total length of the datagrams, including UDP header length
datagram_ids?:Array<uint32>
}
Note: for more details on "datagram_ids", see Section 5.3.10.
5.3.12. datagram_dropped
Importance: Extra
When we drop a UDP-level datagram. This is typically if it does not
contain a valid QUIC packet (in that case, use packet_dropped
instead).
Data:
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{
raw?:RawInfo
}
5.3.13. stream_state_updated
Importance: Base
This event is emitted whenever the internal state of a QUIC stream is
updated, as described in QUIC transport draft-23 section 3. Most of
this can be inferred from several types of frames going over the
wire, but it's much easier to have explicit signals for these state
changes.
Data:
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{
stream_id:uint64,
stream_type?:"unidirectional"|"bidirectional", // mainly useful when opening the stream
old?:StreamState,
new:StreamState,
stream_side?:"sending"|"receiving"
}
enum StreamState {
// bidirectional stream states, draft-23 3.4.
idle,
open,
half_closed_local,
half_closed_remote,
closed,
// sending-side stream states, draft-23 3.1.
ready,
send,
data_sent,
reset_sent,
reset_received,
// receive-side stream states, draft-23 3.2.
receive,
size_known,
data_read,
reset_read,
// both-side states
data_received,
// qlog-defined
destroyed // memory actually freed
}
Note: QUIC implementations SHOULD mainly log the simplified
bidirectional (HTTP/2-alike) stream states (e.g., idle, open, closed)
instead of the more finegrained stream states (e.g., data_sent,
reset_received). These latter ones are mainly for more in-depth
debugging. Tools SHOULD be able to deal with both types equally.
5.3.14. frames_processed
Importance: Extra
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This event's main goal is to prevent a large proliferation of
specific purpose events (e.g., packets_acknowledged,
flow_control_updated, stream_data_received). We want to give
implementations the opportunity to (selectively) log this type of
signal without having to log packet-level details (e.g., in
packet_received). Since for almost all cases, the effects of
applying a frame to the internal state of an implementation can be
inferred from that frame's contents, we aggregate these events in
this single "frames_processed" event.
Note: This event can be used to signal internal state change not
resulting directly from the actual "parsing" of a frame (e.g., the
frame could have been parsed, data put into a buffer, then later
processed, then logged with this event).
Note: Implementations logging "packet_received" and which include all
of the packet's constituent frames therein, are not expected to emit
this "frames_processed" event (contrary to the HTTP-level
"frames_parsed" event). Rather, implementations not wishing to log
full packets or that wish to explicitly convey extra information
about when frames are processed (if not directly tied to their
reception) can use this event.
Note: for some events, this approach will lose some information
(e.g., for which encryption level are packets being acknowledged?).
If this information is important, please use the packet_received
event instead.
Note: in some implementations, it can be difficult to log frames
directly, even when using packet_sent and packet_received events.
For these cases, this event also contains the direct packet_number
field, which can be used to more explicitly link this event to the
packet_sent/received events.
Data:
{
frames:Array<QuicFrame>, // see appendix for the definitions
packet_number?:uint64
}
5.3.15. data_moved
Importance: Base
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Used to indicate when data moves between the different layers (for
example passing from HTTP/3 to QUIC stream buffers and vice versa) or
between HTTP/3 and the actual user application on top (for example a
browser engine). This helps make clear the flow of data, how long
data remains in various buffers and the overheads introduced by
individual layers.
For example, this helps make clear whether received data on a QUIC
stream is moved to the HTTP layer immediately (for example per
received packet) or in larger batches (for example, all QUIC packets
are processed first and afterwards the HTTP layer reads from the
streams with newly available data). This in turn can help identify
bottlenecks or scheduling problems.
Data:
{
stream_id?:uint64,
offset?:uint64,
length?:uint64, // byte length of the moved data
from?:string, // typically: use either of "application","http","transport"
to?:string, // typically: use either of "application","http","transport"
data?:bytes // raw bytes that were transferred
}
Note: we do not for example use a "direction" field (with values "up"
and "down") to specify the data flow. This is because in some
optimized implementations, data might skip some individual layers.
Additionally, using explicit "from" and "to" fields is more flexible
and allows the definition of other conceptual "layers" (for example
to indicate data from QUIC CRYPTO frames being passed to a TLS
library ("security") or from HTTP/3 to QPACK ("qpack")).
Note: this event type is part of the "transport" category, but really
spans all the different layers. This means we have a few leaky
abstractions here (for example, the stream_id or stream offset might
not be available at some logging points, or the raw data might not be
in a byte-array form). In these situations, implementers can decide
to define new, in-context fields to aid in manual debugging.
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5.4. recovery
Note: most of the events in this category are kept generic to support
different recovery approaches and various congestion control
algorithms. Tool creators SHOULD make an effort to support and
visualize even unknown data in these events (e.g., plot unknown
congestion states by name on a timeline visualization).
5.4.1. parameters_set
Importance: Base
This event groups initial parameters from both loss detection and
congestion control into a single event. All these settings are
typically set once and never change. Implementation that do, for
some reason, change these parameters during execution, MAY emit the
parameters_set event twice.
Data:
{
// Loss detection, see recovery draft-23, Appendix A.2
reordering_threshold?:uint16, // in amount of packets
time_threshold?:float, // as RTT multiplier
timer_granularity?:uint16, // in ms
initial_rtt?:float, // in ms
// congestion control, Appendix B.1.
max_datagram_size?:uint32, // in bytes // Note: this could be updated after pmtud
initial_congestion_window?:uint64, // in bytes
minimum_congestion_window?:uint32, // in bytes // Note: this could change when max_datagram_size changes
loss_reduction_factor?:float,
persistent_congestion_threshold?:uint16 // as PTO multiplier
}
Additionally, this event can contain any number of unspecified fields
to support different recovery approaches.
5.4.2. metrics_updated
Importance: Core
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This event is emitted when one or more of the observable recovery
metrics changes value. This event SHOULD group all possible metric
updates that happen at or around the same time in a single event
(e.g., if min_rtt and smoothed_rtt change at the same time, they
should be bundled in a single metrics_updated entry, rather than
split out into two). Consequently, a metrics_updated event is only
guaranteed to contain at least one of the listed metrics.
Data:
{
// Loss detection, see recovery draft-23, Appendix A.3
min_rtt?:float, // in ms or us, depending on the overarching qlog's configuration
smoothed_rtt?:float, // in ms or us, depending on the overarching qlog's configuration
latest_rtt?:float, // in ms or us, depending on the overarching qlog's configuration
rtt_variance?:float, // in ms or us, depending on the overarching qlog's configuration
pto_count?:uint16,
// Congestion control, Appendix B.2.
congestion_window?:uint64, // in bytes
bytes_in_flight?:uint64,
ssthresh?:uint64, // in bytes
// qlog defined
packets_in_flight?:uint64, // sum of all packet number spaces
pacing_rate?:uint64 // in bps
}
Note: to make logging easier, implementations MAY log values even if
they are the same as previously reported values (e.g., two subsequent
METRIC_UPDATE entries can both report the exact same value for
min_rtt). However, applications SHOULD try to log only actual
updates to values.
Additionally, this event can contain any number of unspecified fields
to support different recovery approaches.
5.4.3. congestion_state_updated
Importance: Base
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This event signifies when the congestion controller enters a
significant new state and changes its behaviour. This event's
definition is kept generic to support different Congestion Control
algorithms. For example, for the algorithm defined in the Recovery
draft ("enhanced" New Reno), the following states are defined:
* slow_start
* congestion_avoidance
* application_limited
* recovery
Data:
{
old?:string,
new:string
}
The "trigger" field SHOULD be logged if there are multiple ways in
which a state change can occur but MAY be omitted if a given state
can only be due to a single event occuring (e.g., slow start is
exited only when ssthresh is exceeded).
Some triggers for ("enhanced" New Reno):
* persistent_congestion
* ECN
5.4.4. loss_timer_updated
Importance: Extra
This event is emitted when a recovery loss timer changes state. The
three main event types are:
* set: the timer is set with a delta timeout for when it will
trigger next
* expired: when the timer effectively expires after the delta
timeout
* cancelled: when a timer is cancelled (e.g., all outstanding
packets are acknowledged, start idle period)
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Note: to indicate an active timer's timeout update, a new "set" event
is used.
Data:
{
timer_type?:"ack"|"pto", // called "mode" in draft-23 A.9.
packet_number_space?: PacketNumberSpace,
event_type:"set"|"expired"|"cancelled",
delta?:float // if event_type === "set": delta time in ms or us (see configuration) from this event's timestamp until when the timer will trigger
}
TODO: how about CC algo's that use multiple timers? How generic do
these events need to be? Just support QUIC-style recovery from the
spec or broader?
TODO: read up on the loss detection logic in draft-27 onward and see
if this suffices
5.4.5. packet_lost
Importance: Core
This event is emitted when a packet is deemed lost by loss detection.
Data:
{
header?:PacketHeader, // should include at least the packet_type and packet_number
// not all implementations will keep track of full packets, so these are optional
frames?:Array<QuicFrame> // see appendix for the definitions
}
For this event, the "trigger" field SHOULD be set (for example to one
of the values below), as this helps tremendously in debugging.
Triggers:
* "reordering_threshold",
* "time_threshold"
* "pto_expired" // draft-23 section 5.3.1, MAY
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5.4.6. marked_for_retransmit
Importance: Extra
This event indicates which data was marked for retransmit upon
detecing a packet loss (see packet_lost). Similar to our reasoning
for the "frames_processed" event, in order to keep the amount of
different events low, we group this signal for all types of
retransmittable data in a single event based on existing QUIC frame
definitions.
Implementations retransmitting full packets or frames directly can
just log the consituent frames of the lost packet here (or do away
with this event and use the contents of the packet_lost event
instead). Conversely, implementations that have more complex logic
(e.g., marking ranges in a stream's data buffer as in-flight), or
that do not track sent frames in full (e.g., only stream offset +
length), can translate their internal behaviour into the appropriate
frame instance here even if that frame was never or will never be put
on the wire.
Note: much of this data can be inferred if implementations log
packet_sent events (e.g., looking at overlapping stream data offsets
and length, one can determine when data was retransmitted).
Data:
{
frames:Array<QuicFrame>, // see appendix for the definitions
}
6. HTTP/3 event definitions
6.1. http
Note: like all category values, the "http" category is written in
lowercase.
6.1.1. parameters_set
Importance: Base
This event contains HTTP/3 and QPACK-level settings, mostly those
received from the HTTP/3 SETTINGS frame. All these parameters are
typically set once and never change. However, they are typically set
at different times during the connection, so there can be several
instances of this event with different fields set.
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Note that some settings have two variations (one set locally, one
requested by the remote peer). This is reflected in the "owner"
field. As such, this field MUST be correct for all settings included
a single event instance. If you need to log settings from two sides,
you MUST emit two separate event instances.
Data:
{
owner?:"local" | "remote",
max_header_list_size?:uint64, // from SETTINGS_MAX_HEADER_LIST_SIZE
max_table_capacity?:uint64, // from SETTINGS_QPACK_MAX_TABLE_CAPACITY
blocked_streams_count?:uint64, // from SETTINGS_QPACK_BLOCKED_STREAMS
// qlog-defined
waits_for_settings?:boolean // indicates whether this implementation waits for a SETTINGS frame before processing requests
}
Note: enabling server push is not explicitly done in HTTP/3 by use of
a setting or parameter. Instead, it is communicated by use of the
MAX_PUSH_ID frame, which should be logged using the frame_created and
frame_parsed events below.
Additionally, this event can contain any number of unspecified
fields. This is to reflect setting of for example unknown (greased)
settings or parameters of (proprietary) extensions.
6.1.2. parameters_restored
Importance: Base
When using QUIC 0-RTT, clients are expected to remember and reuse the
server's SETTINGs from the previous connection. This event is used
to indicate which settings were restored and to which values when
utilizing 0-RTT.
Data:
{
max_header_list_size?:uint64,
max_table_capacity?:uint64,
blocked_streams_count?:uint64
}
Note that, like for parameters_set above, this event can contain any
number of unspecified fields to allow for additional and custom
settings.
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6.1.3. stream_type_set
Importance: Base
Emitted when a stream's type becomes known. This is typically when a
stream is opened and the stream's type indicator is sent or received.
Note: most of this information can also be inferred by looking at a
stream's id, since id's are strictly partitioned at the QUIC level.
Even so, this event has a "Base" importance because it helps a lot in
debugging to have this information clearly spelled out.
Data:
{
stream_id:uint64,
owner?:"local"|"remote"
old?:StreamType,
new:StreamType,
associated_push_id?:uint64 // only when new == "push"
}
enum StreamType {
data, // bidirectional request-response streams
control,
push,
reserved,
qpack_encode,
qpack_decode
}
6.1.4. frame_created
Importance: Core
HTTP equivalent to the packet_sent event. This event is emitted when
the HTTP/3 framing actually happens. Note: this is not necessarily
the same as when the HTTP/3 data is passed on to the QUIC layer. For
that, see the "data_moved" event.
Data:
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{
stream_id:uint64,
length?:uint64, // payload byte length of the frame
frame:HTTP3Frame, // see appendix for the definitions,
raw?:RawInfo
}
Note: in HTTP/3, DATA frames can have arbitrarily large lengths to
reduce frame header overhead. As such, DATA frames can span many
QUIC packets and can be created in a streaming fashion. In this
case, the frame_created event is emitted once for the frame header,
and further streamed data is indicated using the data_moved event.
6.1.5. frame_parsed
Importance: Core
HTTP equivalent to the packet_received event. This event is emitted
when we actually parse the HTTP/3 frame. Note: this is not
necessarily the same as when the HTTP/3 data is actually received on
the QUIC layer. For that, see the "data_moved" event.
Data:
{
stream_id:uint64,
length?:uint64, // payload byte length of the frame
frame:HTTP3Frame, // see appendix for the definitions,
raw?:RawInfo
}
Note: in HTTP/3, DATA frames can have arbitrarily large lengths to
reduce frame header overhead. As such, DATA frames can span many
QUIC packets and can be processed in a streaming fashion. In this
case, the frame_parsed event is emitted once for the frame header,
and further streamed data is indicated using the data_moved event.
6.1.6. push_resolved
Importance: Extra
This event is emitted when a pushed resource is successfully claimed
(used) or, conversely, abandoned (rejected) by the application on top
of HTTP/3 (e.g., the web browser). This event is added to help debug
problems with unexpected PUSH behaviour, which is commonplace with
HTTP/2.
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{
push_id?:uint64,
stream_id?:uint64, // in case this is logged from a place that does not have access to the push_id
decision:"claimed"|"abandoned"
}
6.2. qpack
Note: like all category values, the "qpack" category is written in
lowercase.
The QPACK events mainly serve as an aid to debug low-level QPACK
issues. The higher-level, plaintext header values SHOULD (also) be
logged in the http.frame_created and http.frame_parsed event data
(instead).
Note: qpack does not have its own parameters_set event. This was
merged with http.parameters_set for brevity, since qpack is a
required extension for HTTP/3 anyway. Other HTTP/3 extensions MAY
also log their SETTINGS fields in http.parameters_set or MAY define
their own events.
6.2.1. state_updated
Importance: Base
This event is emitted when one or more of the internal QPACK
variables changes value. Note that some variables have two
variations (one set locally, one requested by the remote peer). This
is reflected in the "owner" field. As such, this field MUST be
correct for all variables included a single event instance. If you
need to log settings from two sides, you MUST emit two separate event
instances.
Data:
{
owner:"local" | "remote",
dynamic_table_capacity?:uint64,
dynamic_table_size?:uint64, // effective current size, sum of all the entries
known_received_count?:uint64,
current_insert_count?:uint64
}
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6.2.2. stream_state_updated
Importance: Core
This event is emitted when a stream becomes blocked or unblocked by
header decoding requests or QPACK instructions.
Note: This event is of "Core" importance, as it might have a large
impact on HTTP/3's observed performance.
Data:
{
stream_id:uint64,
state:"blocked"|"unblocked" // streams are assumed to start "unblocked" until they become "blocked"
}
6.2.3. dynamic_table_updated
Importance: Extra
This event is emitted when one or more entries are inserted or
evicted from QPACK's dynamic table.
Data:
{
owner:"local" | "remote", // local = the encoder's dynamic table. remote = the decoder's dynamic table
update_type:"inserted"|"evicted",
entries:Array<DynamicTableEntry>
}
class DynamicTableEntry {
index:uint64;
name?:string | bytes;
value?:string | bytes;
}
6.2.4. headers_encoded
Importance: Base
This event is emitted when an uncompressed header block is encoded
successfully.
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Note: this event has overlap with http.frame_created for the
HeadersFrame type. When outputting both events, implementers MAY
omit the "headers" field in this event.
Data:
{
stream_id?:uint64,
headers?:Array<HTTPHeader>,
block_prefix:QPackHeaderBlockPrefix,
header_block:Array<QPackHeaderBlockRepresentation>,
length?:uint32,
raw?:bytes
}
6.2.5. headers_decoded
Importance: Base
This event is emitted when a compressed header block is decoded
successfully.
Note: this event has overlap with http.frame_parsed for the
HeadersFrame type. When outputting both events, implementers MAY
omit the "headers" field in this event.
Data:
{
stream_id?:uint64,
headers?:Array<HTTPHeader>,
block_prefix:QPackHeaderBlockPrefix,
header_block:Array<QPackHeaderBlockRepresentation>,
length?:uint32,
raw?:bytes
}
6.2.6. instruction_created
Importance: Base
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This event is emitted when a QPACK instruction (both decoder and
encoder) is created and added to the encoder/decoder stream.
Data:
{
instruction:QPackInstruction // see appendix for the definitions,
length?:uint32,
raw?:bytes
}
Note: encoder/decoder semantics and stream_id's are implicit in
either the instruction types or can be logged via other events (e.g.,
http.stream_type_set)
6.2.7. instruction_parsed
Importance: Base
This event is emitted when a QPACK instruction (both decoder and
encoder) is read from the encoder/decoder stream.
Data:
{
instruction:QPackInstruction // see appendix for the definitions,
length?:uint32,
raw?:bytes
}
Note: encoder/decoder semantics and stream_id's are implicit in
either the instruction types or can be logged via other events (e.g.,
http.stream_type_set)
7. Generic events and Simulation indicators
7.1. generic
The main goal of the events in this category is to allow
implementations to fully replace their existing text-based logging by
qlog. This is done by providing events to log generic strings for
typical well-known logging levels (error, warning, info, debug,
verbose).
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7.1.1. error
Importance: Core
Used to log details of an internal error. For errors that
effectively lead to the closure of a QUIC connection, it is
recommended to use transport:connection_closed instead.
Data:
{
code?:uint32,
message?:string
}
7.1.2. warning
Importance: Base
Used to log details of an internal warning that might not get
reflected on the wire.
Data:
{
code?:uint32,
message?:string
}
7.1.3. info
Importance: Extra
Used mainly for implementations that want to use qlog as their one
and only logging format but still want to support unstructured string
messages.
Data:
{
message:string
}
7.1.4. debug
Importance: Extra
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Used mainly for implementations that want to use qlog as their one
and only logging format but still want to support unstructured string
messages.
Data:
{
message:string
}
7.1.5. verbose
Importance: Extra
Used mainly for implementations that want to use qlog as their one
and only logging format but still want to support unstructured string
messages.
Data:
{
message:string
}
7.2. simulation
When evaluating a protocol evaluation, one typically sets up a series
of interoperability or benchmarking tests, in which the test
situations can change over time. For example, the network bandwidth
or latency can vary during the test, or the network can be fully
disable for a short time. In these setups, it is useful to know when
exactly these conditions are triggered, to allow for proper
correlation with other events.
7.2.1. scenario
Importance: Extra
Used to specify which specific scenario is being tested at this
particular instance. This could also be reflected in the top-level
qlog's "summary" or "configuration" fields, but having a separate
event allows easier aggregation of several simulations into one
trace.
{
name?:string,
details?:any
}
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7.2.2. marker
Importance: Extra
Used to indicate when specific emulation conditions are triggered at
set times (e.g., at 3 seconds in 2% packet loss is introduced, at 10s
a NAT rebind is triggered).
{
type?:string,
message?:string
}
8. Security Considerations
TBD
9. IANA Considerations
TBD
10. References
10.1. Normative References
[QLOG-MAIN]
Marx, R., Ed., "Main logging schema for qlog", Work in
Progress, Internet-Draft, draft-marx-qlog-main-schema-02,
2 November 2020, <https://tools.ietf.org/html/draft-marx-
qlog-main-schema-02>.
[QUIC-HTTP]
Bishop, M., Ed., "Hypertext Transfer Protocol Version 3
(HTTP/3)", Work in Progress, Internet-Draft, draft-ietf-
quic-http-32, 1 October 2020,
<https://tools.ietf.org/html/draft-ietf-quic-http-32>.
[QUIC-QPACK]
Frindell, A., Ed., "QPACK: Header Compression for HTTP/3",
Work in Progress, Internet-Draft, draft-ietf-quic-qpack-
19, 20 October 2020,
<https://tools.ietf.org/html/draft-ietf-quic-qpack-19>.
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[QUIC-TRANSPORT]
Iyengar, J., Ed. and M. Thomson, Ed., "QUIC: A UDP-Based
Multiplexed and Secure Transport", Work in Progress,
Internet-Draft, draft-ietf-quic-transport-32, 1 October
2020, <https://tools.ietf.org/html/draft-ietf-quic-
transport-32>.
10.2. Informative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
Appendix A. QUIC data field definitions
A.1. IPAddress
class IPAddress : string | bytes;
// an IPAddress can either be a "human readable" form (e.g., "127.0.0.1" for v4 or "2001:0db8:85a3:0000:0000:8a2e:0370:7334" for v6) or use a raw byte-form (as the string forms can be ambiguous)
A.2. PacketType
enum PacketType {
initial,
handshake,
zerortt = "0RTT",
onertt = "1RTT",
retry,
version_negotiation,
stateless_reset,
unknown
}
A.3. PacketNumberSpace
enum PacketNumberSpace {
initial,
handshake,
application_data
}
A.4. PacketHeader
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class PacketHeader {
// Note: short vs long header is implicit through PacketType
packet_type: PacketType;
packet_number: uint64;
flags?: uint8; // the bit flags of the packet headers (spin bit, key update bit, etc. up to and including the packet number length bits if present) interpreted as a single 8-bit integer
token?:Token; // only if packet_type == initial
length?: uint16, // only if packet_type == initial || handshake || 0RTT. Signifies length of the packet_number plus the payload.
// only if present in the header
// if correctly using transport:connection_id_updated events,
// dcid can be skipped for 1RTT packets
version?: bytes; // e.g., "ff00001d" for draft-29
scil?: uint8;
dcil?: uint8;
scid?: bytes;
dcid?: bytes;
}
A.5. Token
class Token {
type?:"retry"|"resumption"|"stateless_reset";
length?:uint32; // byte length of the token
data?:bytes; // raw byte value of the token
details?:any; // decoded fields included in the token (typically: peer's IP address, creation time)
}
The token carried in an Initial packet can either be a retry token
from a Retry packet, a stateless reset token from a Stateless Reset
packet or one originally provided by the server in a NEW_TOKEN frame
used when resuming a connection (e.g., for address validation
purposes). Retry and resumption tokens typically contain encoded
metadata to check the token's validity when it is used, but this
metadata and its format is implementation specific. For that, this
field includes a general-purpose "details" field.
A.6. KeyType
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enum KeyType {
server_initial_secret,
client_initial_secret,
server_handshake_secret,
client_handshake_secret,
server_0rtt_secret,
client_0rtt_secret,
server_1rtt_secret,
client_1rtt_secret
}
A.7. QUIC Frames
type QuicFrame = PaddingFrame | PingFrame | AckFrame | ResetStreamFrame | StopSendingFrame | CryptoFrame | NewTokenFrame | StreamFrame | MaxDataFrame | MaxStreamDataFrame | MaxStreamsFrame | DataBlockedFrame | StreamDataBlockedFrame | StreamsBlockedFrame | NewConnectionIDFrame | RetireConnectionIDFrame | PathChallengeFrame | PathResponseFrame | ConnectionCloseFrame | HandshakeDoneFrame | UnknownFrame;
A.7.1. PaddingFrame
In QUIC, PADDING frames are simply identified as a single byte of
value 0. As such, each padding byte could be theoretically
interpreted and logged as an individual PaddingFrame.
However, as this leads to heavy logging overhead, implementations
SHOULD instead emit just a single PaddingFrame and set the
payload_length property to the amount of PADDING bytes/frames
included in the packet.
class PaddingFrame{
frame_type:string = "padding";
length?:uint32; // total frame length, including frame header
payload_length?:uint32;
}
A.7.2. PingFrame
class PingFrame{
frame_type:string = "ping";
length?:uint32; // total frame length, including frame header
payload_length?:uint32;
}
A.7.3. AckFrame
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class AckFrame{
frame_type:string = "ack";
ack_delay?:float; // in ms
// first number is "from": lowest packet number in interval
// second number is "to": up to and including // highest packet number in interval
// e.g., looks like [[1,2],[4,5]]
acked_ranges?:Array<[uint64, uint64]|[uint64]>;
// ECN (explicit congestion notification) related fields (not always present)
ect1?:uint64;
ect0?:uint64;
ce?:uint64;
length?:uint32; // total frame length, including frame header
payload_length?:uint32;
}
Note: the packet ranges in AckFrame.acked_ranges do not necessarily
have to be ordered (e.g., [[5,9],[1,4]] is a valid value).
Note: the two numbers in the packet range can be the same (e.g.,
[120,120] means that packet with number 120 was ACKed). However, in
that case, implementers SHOULD log [120] instead and tools MUST be
able to deal with both notations.
A.7.4. ResetStreamFrame
class ResetStreamFrame{
frame_type:string = "reset_stream";
stream_id:uint64;
error_code:ApplicationError | uint32;
final_size:uint64; // in bytes
length?:uint32; // total frame length, including frame header
payload_length?:uint32;
}
A.7.5. StopSendingFrame
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class StopSendingFrame{
frame_type:string = "stop_sending";
stream_id:uint64;
error_code:ApplicationError | uint32;
length?:uint32; // total frame length, including frame header
payload_length?:uint32;
}
A.7.6. CryptoFrame
class CryptoFrame{
frame_type:string = "crypto";
offset:uint64;
length:uint64;
payload_length?:uint32;
}
A.7.7. NewTokenFrame
class NewTokenFrame{
frame_type:string = "new_token";
token:Token
}
A.7.8. StreamFrame
class StreamFrame{
frame_type:string = "stream";
stream_id:uint64;
// These two MUST always be set
// If not present in the Frame type, log their default values
offset:uint64;
length:uint64;
// this MAY be set any time, but MUST only be set if the value is "true"
// if absent, the value MUST be assumed to be "false"
fin?:boolean;
raw?:bytes;
}
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A.7.9. MaxDataFrame
class MaxDataFrame{
frame_type:string = "max_data";
maximum:uint64;
}
A.7.10. MaxStreamDataFrame
class MaxStreamDataFrame{
frame_type:string = "max_stream_data";
stream_id:uint64;
maximum:uint64;
}
A.7.11. MaxStreamsFrame
class MaxStreamsFrame{
frame_type:string = "max_streams";
stream_type:string = "bidirectional" | "unidirectional";
maximum:uint64;
}
A.7.12. DataBlockedFrame
class DataBlockedFrame{
frame_type:string = "data_blocked";
limit:uint64;
}
A.7.13. StreamDataBlockedFrame
class StreamDataBlockedFrame{
frame_type:string = "stream_data_blocked";
stream_id:uint64;
limit:uint64;
}
A.7.14. StreamsBlockedFrame
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class StreamsBlockedFrame{
frame_type:string = "streams_blocked";
stream_type:string = "bidirectional" | "unidirectional";
limit:uint64;
}
A.7.15. NewConnectionIDFrame
class NewConnectionIDFrame{
frame_type:string = "new_connection_id";
sequence_number:uint32;
retire_prior_to:uint32;
connection_id_length?:uint8;
connection_id:bytes;
stateless_reset_token?:Token;
}
A.7.16. RetireConnectionIDFrame
class RetireConnectionIDFrame{
frame_type:string = "retire_connection_id";
sequence_number:uint32;
}
A.7.17. PathChallengeFrame
class PathChallengeFrame{
frame_type:string = "path_challenge";
data?:bytes; // always 64-bit
}
A.7.18. PathResponseFrame
class PathResponseFrame{
frame_type:string = "path_response";
data?:bytes; // always 64-bit
}
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A.7.19. ConnectionCloseFrame
raw_error_code is the actual, numerical code. This is useful because
some error types are spread out over a range of codes (e.g., QUIC's
crypto_error).
type ErrorSpace = "transport" | "application";
class ConnectionCloseFrame{
frame_type:string = "connection_close";
error_space?:ErrorSpace;
error_code?:TransportError | ApplicationError | uint32;
raw_error_code?:uint32;
reason?:string;
trigger_frame_type?:uint64 | string; // For known frame types, the appropriate "frame_type" string. For unknown frame types, the hex encoded identifier value
}
A.7.20. HandshakeDoneFrame
class HandshakeDoneFrame{
frame_type:string = "handshake_done";
}
A.7.21. UnknownFrame
class UnknownFrame{
frame_type:string = "unknown";
raw_frame_type:uint64;
raw_length?:uint32;
raw?:bytes;
}
A.7.22. TransportError
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enum TransportError {
no_error,
internal_error,
connection_refused,
flow_control_error,
stream_limit_error,
stream_state_error,
final_size_error,
frame_encoding_error,
transport_parameter_error,
connection_id_limit_error,
protocol_violation,
invalid_token,
application_error,
crypto_buffer_exceeded
}
A.7.23. CryptoError
These errors are defined in the TLS document as "A TLS alert is
turned into a QUIC connection error by converting the one-byte alert
description into a QUIC error code. The alert description is added
to 0x100 to produce a QUIC error code from the range reserved for
CRYPTO_ERROR."
This approach maps badly to a pre-defined enum. As such, we define
the crypto_error string as having a dynamic component here, which
should include the hex-encoded value of the TLS alert description.
enum CryptoError {
crypto_error_{TLS_ALERT}
}
Appendix B. HTTP/3 data field definitions
B.1. HTTP/3 Frames
type HTTP3Frame = DataFrame | HeadersFrame | PriorityFrame | CancelPushFrame | SettingsFrame | PushPromiseFrame | GoAwayFrame | MaxPushIDFrame | DuplicatePushFrame | ReservedFrame | UnknownFrame;
B.1.1. DataFrame
class DataFrame{
frame_type:string = "data";
raw?:bytes;
}
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B.1.2. HeadersFrame
This represents an _uncompressed_, plaintext HTTP Headers frame
(e.g., no QPACK compression is applied).
For example:
headers: [{"name":":path","value":"/"},{"name":":method","value":"GET"},{"name":":authority","value":"127.0.0.1:4433"},{"name":":scheme","value":"https"}]
class HeadersFrame{
frame_type:string = "header";
headers:Array<HTTPHeader>;
}
class HTTPHeader {
name:string;
value:string;
}
B.1.3. CancelPushFrame
class CancelPushFrame{
frame_type:string = "cancel_push";
push_id:uint64;
}
B.1.4. SettingsFrame
class SettingsFrame{
frame_type:string = "settings";
settings:Array<Setting>;
}
class Setting{
name:string;
value:string;
}
B.1.5. PushPromiseFrame
class PushPromiseFrame{
frame_type:string = "push_promise";
push_id:uint64;
headers:Array<HTTPHeader>;
}
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B.1.6. GoAwayFrame
class GoAwayFrame{
frame_type:string = "goaway";
stream_id:uint64;
}
B.1.7. MaxPushIDFrame
class MaxPushIDFrame{
frame_type:string = "max_push_id";
push_id:uint64;
}
B.1.8. DuplicatePushFrame
class DuplicatePushFrame{
frame_type:string = "duplicate_push";
push_id:uint64;
}
B.1.9. ReservedFrame
class ReservedFrame{
frame_type:string = "reserved";
}
B.1.10. UnknownFrame
HTTP/3 re-uses QUIC's UnknownFrame definition, since their values and
usage overlaps.
B.2. ApplicationError
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enum ApplicationError{
http_no_error,
http_general_protocol_error,
http_internal_error,
http_stream_creation_error,
http_closed_critical_stream,
http_frame_unexpected,
http_frame_error,
http_excessive_load,
http_id_error,
http_settings_error,
http_missing_settings,
http_request_rejected,
http_request_cancelled,
http_request_incomplete,
http_early_response,
http_connect_error,
http_version_fallback
}
Appendix C. QPACK DATA type definitions
C.1. QPACK Instructions
Note: the instructions do not have explicit encoder/decoder types,
since there is no overlap between the insturctions of both types in
neither name nor function.
type QPackInstruction = SetDynamicTableCapacityInstruction | InsertWithNameReferenceInstruction | InsertWithoutNameReferenceInstruction | DuplicateInstruction | HeaderAcknowledgementInstruction | StreamCancellationInstruction | InsertCountIncrementInstruction;
C.1.1. SetDynamicTableCapacityInstruction
class SetDynamicTableCapacityInstruction {
instruction_type:string = "set_dynamic_table_capacity";
capacity:uint32;
}
C.1.2. InsertWithNameReferenceInstruction
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class InsertWithNameReferenceInstruction {
instruction_type:string = "insert_with_name_reference";
table_type:"static"|"dynamic";
name_index:uint32;
huffman_encoded_value:boolean;
value_length?:uint32;
value?:string;
}
C.1.3. InsertWithoutNameReferenceInstruction
class InsertWithoutNameReferenceInstruction {
instruction_type:string = "insert_without_name_reference";
huffman_encoded_name:boolean;
name_length?:uint32;
name?:string;
huffman_encoded_value:boolean;
value_length?:uint32;
value?:string;
}
C.1.4. DuplicateInstruction
class DuplicateInstruction {
instruction_type:string = "duplicate";
index:uint32;
}
C.1.5. HeaderAcknowledgementInstruction
class HeaderAcknowledgementInstruction {
instruction_type:string = "header_acknowledgement";
stream_id:uint64;
}
C.1.6. StreamCancellationInstruction
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class StreamCancellationInstruction {
instruction_type:string = "stream_cancellation";
stream_id:uint64;
}
C.1.7. InsertCountIncrementInstruction
class InsertCountIncrementInstruction {
instruction_type:string = "insert_count_increment";
increment:uint32;
}
C.2. QPACK Header compression
type QPackHeaderBlockRepresentation = IndexedHeaderField | LiteralHeaderFieldWithName | LiteralHeaderFieldWithoutName;
C.2.1. IndexedHeaderField
Note: also used for "indexed header field with post-base index"
class IndexedHeaderField {
header_field_type:string = "indexed_header";
table_type:"static"|"dynamic"; // MUST be "dynamic" if is_post_base is true
index:uint32;
is_post_base:boolean = false; // to represent the "indexed header field with post-base index" header field type
}
C.2.2. LiteralHeaderFieldWithName
Note: also used for "Literal header field with post-base name
reference"
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class LiteralHeaderFieldWithName {
header_field_type:string = "literal_with_name";
preserve_literal:boolean; // the 3rd "N" bit
table_type:"static"|"dynamic"; // MUST be "dynamic" if is_post_base is true
name_index:uint32;
huffman_encoded_value:boolean;
value_length?:uint32;
value?:string;
is_post_base:boolean = false; // to represent the "Literal header field with post-base name reference" header field type
}
C.2.3. LiteralHeaderFieldWithoutName
class LiteralHeaderFieldWithoutName {
header_field_type:string = "literal_without_name";
preserve_literal:boolean; // the 3rd "N" bit
huffman_encoded_name:boolean;
name_length?:uint32;
name?:string;
huffman_encoded_value:boolean;
value_length?:uint32;
value?:string;
}
C.2.4. QPackHeaderBlockPrefix
class QPackHeaderBlockPrefix {
required_insert_count:uint32;
sign_bit:boolean;
delta_base:uint32;
}
Appendix D. Change Log
D.1. Since draft-01:
Major changes:
* Moved data_moved from http to transport. Also made the "from" and
"to" fields flexible strings instead of an enum (#111,#65)
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* Moved packet_type fields to PacketHeader. Moved packet_size field
out of PacketHeader to RawInfo:length (#40)
* Made events that need to log packet_type and packet_number use a
header field instead of logging these fields individually
* Added support for logging retry, stateless reset and initial
tokens (#94,#86,#117)
* Moved separate general event categories into a single category
"generic" (#47)
* Added "transport:connection_closed" event (#43,#85,#78,#49)
* Added version_information and alpn_information events
(#85,#75,#28)
* Added parameters_restored events to help clarify 0-RTT behaviour
(#88)
Smaller changes:
* Merged loss_timer events into one loss_timer_updated event
* Field data types are now strongly defined (#10,#39,#36,#115)
* Renamed qpack instruction_received and instruction_sent to
instruction_created and instruction_parsed (#114)
* Updated qpack:dynamic_table_updated.update_type. It now has the
value "inserted" instead of "added" (#113)
* Updated qpack:dynamic_table_updated. It now has an "owner" field
to differentiate encoder vs decoder state (#112)
* Removed push_allowed from http:parameters_set (#110)
* Removed explicit trigger field indications from events, since this
was moved to be a generic property of the "data" field (#80)
* Updated transport:connection_id_updated to be more in line with
other similar events. Also dropped importance from Core to Base
(#45)
* Added length property to PaddingFrame (#34)
* Added packet_number field to transport:frames_processed (#74)
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* Added a way to generically log packet header flags (first 8 bits)
to PacketHeader
* Added additional guidance on which events to log in which
situations (#53)
* Added "simulation:scenario" event to help indicate simulation
details
* Added "packets_acked" event (#107)
* Added "datagram_ids" to the datagram_X and packet_X events to
allow tracking of coalesced QUIC packets (#91)
* Extended connection_state_updated with more fine-grained states
(#49)
D.2. Since draft-00:
* Event and category names are now all lowercase
* Added many new events and their definitions
* "type" fields have been made more specific (especially important
for PacketType fields, which are now called packet_type instead of
type)
* Events are given an importance indicator (issue #22)
* Event names are more consistent and use past tense (issue #21)
* Triggers have been redefined as properties of the "data" field and
updated for most events (issue #23)
Appendix E. Design Variations
TBD
Appendix F. Acknowledgements
Thanks to Marten Seemann, Jana Iyengar, Brian Trammell, Dmitri
Tikhonov, Stephen Petrides, Jari Arkko, Marcus Ihlar, Victor
Vasiliev, Mirja Kuehlewind, Jeremy Laine, Kazu Yamamoto, Christian
Huitema, and Lucas Pardue for their feedback and suggestions.
Author's Address
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Robin Marx
Hasselt University
Email: robin.marx@uhasselt.be
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