Secure Shell (SSH) Protocol Parameters

Created: 2005-06-02
Last Updated: 2024-11-07
Available Formats: XML
HTML
Plain text

Registries included below

Message Numbers
Disconnection Messages Reason Codes and Descriptions
Channel Connection Failure Reason Codes and Descriptions
Extended Channel Data Transfer data_type_code and Data
Pseudo-Terminal Encoded Terminal Modes
Service Names
Authentication Method Names
Connection Protocol Channel Types
Connection Protocol Global Request Names
Connection Protocol Channel Request Names
Signal Names
Connection Protocol Subsystem Names
Key Exchange Method Names
Encryption Algorithm Names
MAC Algorithm Names
Public Key Algorithm Names
Compression Algorithm Names
SSH Public-Key File Header Tags
Publickey Subsystem Request Names
Publickey Subsystem Response Names
Publickey Subsystem Attributes
Publickey Subsystem Status Codes
Extension Names

Message Numbers

Registration Procedure(s)

Standards Action

Reference

[RFC4250]

Available Formats

CSV

Value	Message ID	Reference
0	Reserved
1	SSH_MSG_DISCONNECT	[RFC4253]
2	SSH_MSG_IGNORE	[RFC4253]
3	SSH_MSG_UNIMPLEMENTED	[RFC4253]
4	SSH_MSG_DEBUG	[RFC4253]
5	SSH_MSG_SERVICE_REQUEST	[RFC4253]
6	SSH_MSG_SERVICE_ACCEPT	[RFC4253]
7	SSH_MSG_EXT_INFO	[RFC8308]
8	SSH_MSG_NEWCOMPRESS	[RFC8308]
9-19	Unassigned (Transport layer generic)
20	SSH_MSG_KEXINIT	[RFC4253]
21	SSH_MSG_NEWKEYS	[RFC4253]
22-29	Unassigned (Algorithm negotiation)
30-49	Reserved (key exchange method specific)	[RFC4251]
50	SSH_MSG_USERAUTH_REQUEST	[RFC4252]
51	SSH_MSG_USERAUTH_FAILURE	[RFC4252]
52	SSH_MSG_USERAUTH_SUCCESS	[RFC4252]
53	SSH_MSG_USERAUTH_BANNER	[RFC4252]
54-59	Unassigned (User authentication generic)
60	SSH_MSG_USERAUTH_INFO_REQUEST	[RFC4256]
61	SSH_MSG_USERAUTH_INFO_RESPONSE	[RFC4256]
62-79	Reserved (User authentication method specific)	[RFC4251]
80	SSH_MSG_GLOBAL_REQUEST	[RFC4254]
81	SSH_MSG_REQUEST_SUCCESS	[RFC4254]
82	SSH_MSG_REQUEST_FAILURE	[RFC4254]
83-89	Unassigned (Connection protocol generic)
90	SSH_MSG_CHANNEL_OPEN	[RFC4254]
91	SSH_MSG_CHANNEL_OPEN_CONFIRMATION	[RFC4254]
92	SSH_MSG_CHANNEL_OPEN_FAILURE	[RFC4254]
93	SSH_MSG_CHANNEL_WINDOW_ADJUST	[RFC4254]
94	SSH_MSG_CHANNEL_DATA	[RFC4254]
95	SSH_MSG_CHANNEL_EXTENDED_DATA	[RFC4254]
96	SSH_MSG_CHANNEL_EOF	[RFC4254]
97	SSH_MSG_CHANNEL_CLOSE	[RFC4254]
98	SSH_MSG_CHANNEL_REQUEST	[RFC4254]
99	SSH_MSG_CHANNEL_SUCCESS	[RFC4254]
100	SSH_MSG_CHANNEL_FAILURE	[RFC4254]
101-127	Unassigned (Channel related messages)
128-191	Reserved (for client protocols)
192-255	Reserved for Private Use (local extensions)

Disconnection Messages Reason Codes and Descriptions

Expert(s)

Peter Yee, Markus Stenberg

Reference

[RFC4250][RFC9519]

Note

SSH_MSG_DISCONNECT 'description' and 'reason code' values

Note

Registration requests should be sent to the mailing list described in 
[RFC9519]. If approved, designated experts should notify IANA within 
three weeks. For assistance, please contact iana@iana.org.

Available Formats

CSV

Range	Registration Procedures
0x00000001-0xFDFFFFFF	Expert Review
0xFE000000-0xFFFFFFFF	Reserved for Private Use

Reason Code	Symbolic Name	Reference
0x00000000	Reserved
0x00000001	SSH_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT	[RFC4253]
0x00000002	SSH_DISCONNECT_PROTOCOL_ERROR	[RFC4253]
0x00000003	SSH_DISCONNECT_KEY_EXCHANGE_FAILED	[RFC4253]
0x00000004	SSH_DISCONNECT_RESERVED	[RFC4253]
0x00000005	SSH_DISCONNECT_MAC_ERROR	[RFC4253]
0x00000006	SSH_DISCONNECT_COMPRESSION_ERROR	[RFC4253]
0x00000007	SSH_DISCONNECT_SERVICE_NOT_AVAILABLE	[RFC4253]
0x00000008	SSH_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED	[RFC4253]
0x00000009	SSH_DISCONNECT_HOST_KEY_NOT_VERIFIABLE	[RFC4253]
0x0000000A	SSH_DISCONNECT_CONNECTION_LOST	[RFC4253]
0x0000000B	SSH_DISCONNECT_BY_APPLICATION	[RFC4253]
0x0000000C	SSH_DISCONNECT_TOO_MANY_CONNECTIONS	[RFC4253]
0x0000000D	SSH_DISCONNECT_AUTH_CANCELLED_BY_USER	[RFC4253]
0x0000000E	SSH_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE	[RFC4253]
0x0000000F	SSH_DISCONNECT_ILLEGAL_USER_NAME	[RFC4253]
0x00000010-0xFDFFFFFF	Unassigned
0xFE000000-0xFFFFFFFF	Reserved for Private Use

Channel Connection Failure Reason Codes and Descriptions

Expert(s)

Peter Yee, Markus Stenberg

Reference

[RFC4250][RFC9519]

Note

'reason code' values and 'description' values

Note

Registration requests should be sent to the mailing list described in 
[RFC9519]. If approved, designated experts should notify IANA within 
three weeks. For assistance, please contact iana@iana.org.

Available Formats

CSV

Range	Registration Procedures
0x00000001-0xFDFFFFFF	Expert Review
0xFE000000-0xFFFFFFFF	Reserved for Private Use

Reason Code	Symbolic Name	Reference
0x00000000	Reserved
0x00000001	SSH_OPEN_ADMINISTRATIVELY_PROHIBITED	[RFC4254]
0x00000002	SSH_OPEN_CONNECT_FAILED	[RFC4254]
0x00000003	SSH_OPEN_UNKNOWN_CHANNEL_TYPE	[RFC4254]
0x00000004	SSH_OPEN_RESOURCE_SHORTAGE	[RFC4254]
0x00000005-0xFDFFFFFF	Unassigned
0xFE000000-0xFFFFFFFF	Reserved for Private Use

Extended Channel Data Transfer data_type_code and Data

Expert(s)

Peter Yee, Markus Stenberg

Reference

[RFC4250][RFC9519]

Note

'data_type_code' values and 'data' values

Note

Registration requests should be sent to the mailing list described in 
[RFC9519]. If approved, designated experts should notify IANA within 
three weeks. For assistance, please contact iana@iana.org.

Available Formats

CSV

Range	Registration Procedures
0x00000001-0xFDFFFFFF	Expert Review
0xFE000000-0xFFFFFFFF	Reserved for Private Use

data_type_code	Symbolic Name	Reference
0x00000000	Reserved
0x00000001	SSH_EXTENDED_DATA_STDERR	[RFC4254]
0x00000002-0xFDFFFFFF	Unassigned
0xFE000000-0xFFFFFFFF	Reserved for Private Use

Pseudo-Terminal Encoded Terminal Modes

Registration Procedure(s)

Expert Review

Expert(s)

Peter Yee, Markus Stenberg

Reference

[RFC4250][RFC9519]

Note

opcode and argument values which make up the "encoded terminal modes" values

Note

Registration requests should be sent to the mailing list described in 
[RFC9519]. If approved, designated experts should notify IANA within 
three weeks. For assistance, please contact iana@iana.org.

Available Formats

CSV

Opcode	Argument	Description	Reference	Note
0	TTY_OP_END	Indicates end of options.	[RFC4250]
1	VINTR	Interrupt character; 255 if none. Similarly for the other characters. Not all of these characters are supported on all systems.	[RFC4254]	Section 8
2	VQUIT	The quit character (sends SIGQUIT signal on POSIX systems).	[RFC4254]	Section 8
3	VERASE	Erase the character to left of the cursor.	[RFC4254]	Section 8
4	VKILL	Kill the current input line.	[RFC4254]	Section 8
5	VEOF	End-of-file character (sends EOF from the terminal).	[RFC4254]	Section 8
6	VEOL	End-of-line character in addition to carriage return and/or linefeed.	[RFC4254]	Section 8
7	VEOL2	Additional end-of-line character.	[RFC4254]	Section 8
8	VSTART	Continues paused output (normally control-Q).	[RFC4254]	Section 8
9	VSTOP	Pauses output (normally control-S).	[RFC4254]	Section 8
10	VSUSP	Suspends the current program.	[RFC4254]	Section 8
11	VDSUSP	Another suspend character.	[RFC4254]	Section 8
12	VREPRINT	Reprints the current input line.	[RFC4254]	Section 8
13	VWERASE	Erases a word left of cursor.	[RFC4254]	Section 8
14	VLNEXT	Enter the next character typed literally, even if it is a special character	[RFC4254]	Section 8
15	VFLUSH	Character to flush output.	[RFC4254]	Section 8
16	VSWTCH	Switch to a different shell layer.	[RFC4254]	Section 8
17	VSTATUS	Prints system status line (load, command, pid, etc).	[RFC4254]	Section 8
18	VDISCARD	Toggles the flushing of terminal output.	[RFC4254]	Section 8
19-29	Unassigned
30	IGNPAR	The ignore parity flag. The parameter SHOULD be 0 if this flag is FALSE, and 1 if it is TRUE.	[RFC4254]	Section 8
31	PARMRK	Mark parity and framing errors.	[RFC4254]	Section 8
32	INPCK	Enable checking of parity errors.	[RFC4254]	Section 8
33	ISTRIP	Strip 8th bit off characters.	[RFC4254]	Section 8
34	INLCR	Map NL into CR on input.	[RFC4254]	Section 8
35	IGNCR	Ignore CR on input.	[RFC4254]	Section 8
36	ICRNL	Map CR to NL on input.	[RFC4254]	Section 8
37	IUCLC	Translate uppercase characters to lowercase.	[RFC4254]	Section 8
38	IXON	Enable output flow control.	[RFC4254]	Section 8
39	IXANY	Any char will restart after stop.	[RFC4254]	Section 8
40	IXOFF	Enable input flow control.	[RFC4254]	Section 8
41	IMAXBEL	Ring bell on input queue full.	[RFC4254]	Section 8
42	IUTF8	Terminal input and output is assumed to be encoded in UTF-8.	[RFC8160]
43-49	Unassigned
50	ISIG	Enable signals INTR, QUIT, [D]SUSP.	[RFC4254]	Section 8
51	ICANON	Canonicalize input lines.	[RFC4254]	Section 8
52	XCASE	Enable input and output of uppercase characters by preceding their lowercase equivalents with "\".	[RFC4254]	Section 8
53	ECHO	Enable echoing.	[RFC4254]	Section 8
54	ECHOE	Visually erase chars.	[RFC4254]	Section 8
55	ECHOK	Kill character discards current line.	[RFC4254]	Section 8
56	ECHONL	Echo NL even if ECHO is off.	[RFC4254]	Section 8
57	NOFLSH	Don't flush after interrupt.	[RFC4254]	Section 8
58	TOSTOP	Stop background jobs from output.	[RFC4254]	Section 8
59	IEXTEN	Enable extensions.	[RFC4254]	Section 8
60	ECHOCTL	Echo control characters as ^(Char).	[RFC4254]	Section 8
61	ECHOKE	Visual erase for line kill.	[RFC4254]	Section 8
62	PENDIN	Retype pending input.	[RFC4254]	Section 8
63-69	Unassigned
70	OPOST	Enable output processing.	[RFC4254]	Section 8
71	OLCUC	Convert lowercase to uppercase.	[RFC4254]	Section 8
72	ONLCR	Map NL to CR-NL.	[RFC4254]	Section 8
73	OCRNL	Translate carriage return to newline (output).	[RFC4254]	Section 8
74	ONOCR	Translate newline to carriage return-newline (output).	[RFC4254]	Section 8
75	ONLRET	Newline performs a carriage return (output).	[RFC4254]	Section 8
76-89	Unassigned
90	CS7	7 bit mode.	[RFC4254]	Section 8
91	CS8	8 bit mode.	[RFC4254]	Section 8
92	PARENB	Parity enable.	[RFC4254]	Section 8
93	PARODD	Odd parity, else even.	[RFC4254]	Section 8
94-127	Unassigned
128	TTY_OP_ISPEED	Specifies the input baud rate in bits per second.	[RFC4254]	Section 8
129	TTY_OP_OSPEED	Specifies the output baud rate in bits per second.	[RFC4254]	Section 8
130-255	Unassigned

Service Names

Registration Procedure(s)

Expert Review

Expert(s)

Peter Yee, Markus Stenberg

Reference

[RFC4250][RFC9519]

Note

Registration requests should be sent to the mailing list described in 
[RFC9519]. If approved, designated experts should notify IANA within 
three weeks. For assistance, please contact iana@iana.org.

Available Formats

CSV

Service Name	Reference
ssh-userauth	[RFC4252]
ssh-connection	[RFC4254]

Authentication Method Names

Registration Procedure(s)

Expert Review

Expert(s)

Peter Yee, Markus Stenberg

Reference

[RFC4250][RFC9519]

Note

Registration requests should be sent to the mailing list described in 
[RFC9519]. If approved, designated experts should notify IANA within 
three weeks. For assistance, please contact iana@iana.org.

Available Formats

CSV

Method Name	Reference	Note
publickey	[RFC4252]	Section 7
password	[RFC4252]	Section 8
hostbased	[RFC4252]	Section 9
none	[RFC4252]	Section 5.2
keyboard-interactive	[RFC4256]
gssapi-with-mic	[RFC4462]
gssapi-keyex	[RFC4462]
gssapi	[RFC4462]
external-keyx	[RFC4462]

Connection Protocol Channel Types

Registration Procedure(s)

Expert Review

Expert(s)

Peter Yee, Markus Stenberg

Reference

[RFC4250][RFC9519]

Note

Registration requests should be sent to the mailing list described in 
[RFC9519]. If approved, designated experts should notify IANA within 
three weeks. For assistance, please contact iana@iana.org.

Available Formats

CSV

Channel Type	Reference	Note
session	[RFC4254]	Section 6.1
x11	[RFC4254]	Section 6.3.2
forwarded-tcpip	[RFC4254]	Section 7.2
direct-tcpip	[RFC4254]	Section 7.2

Connection Protocol Global Request Names

Registration Procedure(s)

Expert Review

Expert(s)

Peter Yee, Markus Stenberg

Reference

[RFC4250][RFC9519]

Note

Registration requests should be sent to the mailing list described in 
[RFC9519]. If approved, designated experts should notify IANA within 
three weeks. For assistance, please contact iana@iana.org.

Available Formats

CSV

Request Type	Reference	Note
tcpip-forward	[RFC4254]	Section 7.1
cancel-tcpip-forward	[RFC4254]	Section 7.1

Connection Protocol Channel Request Names

Registration Procedure(s)

Expert Review

Expert(s)

Peter Yee, Markus Stenberg

Reference

[RFC4250][RFC9519]

Note

Registration requests should be sent to the mailing list described in 
[RFC9519]. If approved, designated experts should notify IANA within 
three weeks. For assistance, please contact iana@iana.org.

Available Formats

CSV

Request Type	Reference	Note
pty-req	[RFC4254]	Section 6.2
x11-req	[RFC4254]	Section 6.3.1
env	[RFC4254]	Section 6.4
shell	[RFC4254]	Section 6.5
exec	[RFC4254]	Section 6.5
subsystem	[RFC4254]	Section 6.5
window-change	[RFC4254]	Section 6.7
xon-xoff	[RFC4254]	Section 6.8
signal	[RFC4254]	Section 6.9
exit-status	[RFC4254]	Section 6.10
exit-signal	[RFC4254]	Section 6.10
break	[RFC4335]

Signal Names

Registration Procedure(s)

Expert Review

Expert(s)

Peter Yee, Markus Stenberg

Reference

[RFC4250][RFC9519]

Note

Registration requests should be sent to the mailing list described in 
[RFC9519]. If approved, designated experts should notify IANA within 
three weeks. For assistance, please contact iana@iana.org.

Available Formats

CSV

Signal	Reference
ABRT	[RFC4254]
ALRM	[RFC4254]
FPE	[RFC4254]
HUP	[RFC4254]
ILL	[RFC4254]
INT	[RFC4254]
KILL	[RFC4254]
PIPE	[RFC4254]
QUIT	[RFC4254]
SEGV	[RFC4254]
TERM	[RFC4254]
USR1	[RFC4254]
USR2	[RFC4254]

Connection Protocol Subsystem Names

Registration Procedure(s)

Expert Review

Expert(s)

Peter Yee, Markus Stenberg

Reference

[RFC4250][RFC9519]

Note

Registration requests should be sent to the mailing list described in 
[RFC9519]. If approved, designated experts should notify IANA within 
three weeks. For assistance, please contact iana@iana.org.

Available Formats

CSV

Subsystem Name	Reference
publickey	[RFC4819]
snmp	[RFC5592]
netconf	[RFC6242]
rpki-rtr	[RFC6810]

Key Exchange Method Names

Registration Procedure(s)

Expert Review

Expert(s)

Peter Yee, Markus Stenberg

Reference

[RFC4250][RFC9142][RFC9519]

Note

*All values beginning with the specified string and not containing "@".

Note

“OK to Implement” guidance entries for registrations that pre-date 
[RFC9142] are found in Table 12 in Section 4 of [RFC9142].

Note

When this registry is modified, the YANG module 
"iana-ssh-key-exchange-algs" [IANA registry yang-parameters] must be 
updated as defined in [RFC9644].

Note

Registration requests should be sent to the mailing list described in 
[RFC9519]. If approved, designated experts should notify IANA within 
three weeks. For assistance, please contact iana@iana.org.

Available Formats

CSV

Method Name	Reference	Note	OK to Implement
diffie-hellman-group-exchange-sha1	[RFC4419][RFC8270]	Section 4.1	SHOULD NOT
diffie-hellman-group-exchange-sha256	[RFC4419][RFC8270]	Section 4.2	MAY
diffie-hellman-group1-sha1	[RFC4253]	Section 8.1	SHOULD NOT
diffie-hellman-group14-sha1	[RFC4253]	Section 8.2	MAY
diffie-hellman-group14-sha256	[RFC8268]		MUST
diffie-hellman-group15-sha512	[RFC8268]		MAY
diffie-hellman-group16-sha512	[RFC8268]		SHOULD
diffie-hellman-group17-sha512	[RFC8268]		MAY
diffie-hellman-group18-sha512	[RFC8268]		MAY
ecdh-sha2-*	[RFC5656]		MAY
ecmqv-sha2	[RFC5656]		MAY
gss-group1-sha1-*	[RFC4462][RFC8732]		SHOULD NOT
gss-group14-sha1-*	[RFC4462][RFC8732]		SHOULD NOT
gss-gex-sha1-*	[RFC4462][RFC8732]		SHOULD NOT
gss-	[RFC4462]	Section 2.6	reserved
rsa1024-sha1	[RFC4432]		MUST NOT
rsa2048-sha256	[RFC4432]		MAY
ext-info-s	[RFC8308]	Section 2	SHOULD
ext-info-c	[RFC8308]	Section 2	SHOULD
gss-group14-sha256-*	[RFC8732]		SHOULD
gss-group15-sha512-*	[RFC8732]		MAY
gss-group16-sha512-*	[RFC8732]		MAY
gss-group17-sha512-*	[RFC8732]		MAY
gss-group18-sha512-*	[RFC8732]		MAY
gss-nistp256-sha256-*	[RFC8732]		SHOULD
gss-nistp384-sha384-*	[RFC8732]		SHOULD
gss-nistp521-sha512-*	[RFC8732]		SHOULD
gss-curve25519-sha256-*	[RFC8732]		SHOULD
gss-curve448-sha512-*	[RFC8732]		MAY
curve25519-sha256	[RFC8731]		SHOULD
curve448-sha512	[RFC8731]		MAY
ecdh-sha2-nistp256	[RFC5656]		SHOULD
ecdh-sha2-nistp384	[RFC5656]		SHOULD
ecdh-sha2-nistp521	[RFC5656]		SHOULD
sntrup761x25519-sha512	[draft-josefsson-ntruprime-ssh-02]		MAY
mlkem768nistp256-sha256	[draft-kampanakis-curdle-ssh-pq-ke-04]		MAY
mlkem1024nistp384-sha384	[draft-kampanakis-curdle-ssh-pq-ke-04]		MAY
mlkem768x25519-sha256	[draft-kampanakis-curdle-ssh-pq-ke-04]		MAY

Encryption Algorithm Names

Registration Procedure(s)

Expert Review

Expert(s)

Peter Yee, Markus Stenberg

Reference

[RFC4250][RFC9519]

Note

When this registry is modified, the YANG module 
"iana-ssh-encryption-algs" [IANA registry yang-parameters] must be 
updated as defined in [RFC9644].

Note

Registration requests should be sent to the mailing list described in 
[RFC9519]. If approved, designated experts should notify IANA within 
three weeks. For assistance, please contact iana@iana.org.

Available Formats

CSV

Encryption Algorithm Name	Reference	Note
3des-cbc	[RFC4253]	Section 6.3
blowfish-cbc	[RFC4253]	Section 6.3
twofish256-cbc	[RFC4253]	Section 6.3
twofish-cbc	[RFC4253]	Section 6.3
twofish192-cbc	[RFC4253]	Section 6.3
twofish128-cbc	[RFC4253]	Section 6.3
aes256-cbc	[RFC4253]	Section 6.3
aes192-cbc	[RFC4253]	Section 6.3
aes128-cbc	[RFC4253]	Section 6.3
serpent256-cbc	[RFC4253]	Section 6.3
serpent192-cbc	[RFC4253]	Section 6.3
serpent128-cbc	[RFC4253]	Section 6.3
arcfour	[RFC8758]	HISTORIC
idea-cbc	[RFC4253]	Section 6.3
cast128-cbc	[RFC4253]	Section 6.3
none	[RFC4253]	Section 6.3
des-cbc	[FIPS-46-3]	HISTORIC, See page 4
arcfour128	[RFC8758]	HISTORIC
arcfour256	[RFC8758]	HISTORIC
aes128-ctr	[RFC4344]
aes192-ctr	[RFC4344]
aes256-ctr	[RFC4344]
3des-ctr	[RFC4344]
blowfish-ctr	[RFC4344]
twofish128-ctr	[RFC4344]
twofish192-ctr	[RFC4344]
twofish256-ctr	[RFC4344]
serpent128-ctr	[RFC4344]
serpent192-ctr	[RFC4344]
serpent256-ctr	[RFC4344]
idea-ctr	[RFC4344]
cast128-ctr	[RFC4344]
AEAD_AES_128_GCM	[RFC5647]	Section 6.1
AEAD_AES_256_GCM	[RFC5647]	Section 6.2
chacha20-poly1305	[draft-josefsson-ssh-chacha20-poly1305-openssh-01]

MAC Algorithm Names

Registration Procedure(s)

Expert Review

Expert(s)

Peter Yee, Markus Stenberg

Reference

[RFC4250][RFC9519]

Note

When this registry is modified, the YANG module "iana-ssh-mac-algs" 
[IANA registry yang-parameters] must be updated as defined in 
[RFC9644].

Note

Registration requests should be sent to the mailing list described in 
[RFC9519]. If approved, designated experts should notify IANA within 
three weeks. For assistance, please contact iana@iana.org.

Available Formats

CSV

MAC Algorithm Name	Reference	Note
hmac-sha1	[RFC4253]	Section 6.4
hmac-sha1-96	[RFC4253]	Section 6.4
hmac-md5	[RFC4253]	Section 6.4
hmac-md5-96	[RFC4253]	Section 6.4
none	[RFC4253]	Section 6.4
AEAD_AES_128_GCM	[RFC5647]	Section 6.1
AEAD_AES_256_GCM	[RFC5647]	Section 6.2
hmac-sha2-256	[RFC6668]	Section 2
hmac-sha2-512	[RFC6668]	Section 2

Public Key Algorithm Names

Registration Procedure(s)

Expert Review

Expert(s)

Peter Yee, Markus Stenberg

Reference

[RFC4250][RFC9519]

Note

*All values beginning with the specified string and not containing "@".

Note

When this registry is modified, the YANG module 
"iana-ssh-public-key-algs" [IANA registry yang-parameters] must be 
updated as defined in [RFC9644].

Note

Registration requests should be sent to the mailing list described in 
[RFC9519]. If approved, designated experts should notify IANA within 
three weeks. For assistance, please contact iana@iana.org.

Available Formats

CSV

Public Key Algorithm Name	Public Key Format	Reference	Note
ssh-dss	ssh-dss	[RFC4253]	Section 6.6
ssh-rsa	ssh-rsa	[RFC4253]	Section 6.6
rsa-sha2-256	ssh-rsa	[RFC8332]	Section 3
rsa-sha2-512	ssh-rsa	[RFC8332]	Section 3
spki-sign-rsa	spki-sign-rsa	[RFC4253]	Section 6.6
spki-sign-dss	spki-sign-dss	[RFC4253]	Section 6.6
pgp-sign-rsa	pgp-sign-rsa	[RFC4253]	Section 6.6
pgp-sign-dss	pgp-sign-dss	[RFC4253]	Section 6.6
null	null	[RFC4462]	Section 5
ecdsa-sha2-*	ecdsa-sha2-*	[RFC5656]
x509v3-ssh-dss	x509v3-ssh-dss	[RFC6187]
x509v3-ssh-rsa	x509v3-ssh-rsa	[RFC6187]
x509v3-rsa2048-sha256	x509v3-rsa2048-sha256	[RFC6187]
x509v3-ecdsa-sha2-*	x509v3-ecdsa-sha2-*	[RFC6187]
ssh-ed25519	ssh-ed25519	[RFC8709]
ssh-ed448	ssh-ed448	[RFC8709]

Compression Algorithm Names

Registration Procedure(s)

Expert Review

Expert(s)

Peter Yee, Markus Stenberg

Reference

[RFC4250][RFC9519]

Note

Registration requests should be sent to the mailing list described in 
[RFC9519]. If approved, designated experts should notify IANA within 
three weeks. For assistance, please contact iana@iana.org.

Available Formats

CSV

Compression Algorithm Name	Reference	Note
none	[RFC4253]	Section 6.2
zlib	[RFC4253]	Section 6.2

SSH Public-Key File Header Tags

Registration Procedure(s)

Expert Review

Expert(s)

Peter Yee, Markus Stenberg

Reference

[RFC4716][RFC9519]

Note

Tags beginning with x- Reserved for Private Use

Note

Registration requests should be sent to the mailing list described in 
[RFC9519]. If approved, designated experts should notify IANA within 
three weeks. For assistance, please contact iana@iana.org.

Available Formats

CSV

Header Tag	Reference	Note
subject	[RFC4716]	Section 3.3.1
comment	[RFC4716]	Section 3.3.2

Publickey Subsystem Request Names

Registration Procedure(s)

Expert Review

Expert(s)

Peter Yee, Markus Stenberg

Reference

[RFC4819][RFC9519]

Note

Registration requests should be sent to the mailing list described in 
[RFC9519]. If approved, designated experts should notify IANA within 
three weeks. For assistance, please contact iana@iana.org.

Available Formats

CSV

Request Name	Reference
version	[RFC4819]
add	[RFC4819]
remove	[RFC4819]
list	[RFC4819]
listattributes	[RFC4819]

Publickey Subsystem Response Names

Registration Procedure(s)

Expert Review

Expert(s)

Peter Yee, Markus Stenberg

Reference

[RFC4819][RFC9519]

Note

Registration requests should be sent to the mailing list described in 
[RFC9519]. If approved, designated experts should notify IANA within 
three weeks. For assistance, please contact iana@iana.org.

Available Formats

CSV

Response Name	Reference
version	[RFC4819]
status	[RFC4819]
publickey	[RFC4819]
attribute	[RFC4819]

Publickey Subsystem Attributes

Registration Procedure(s)

Expert Review

Expert(s)

Peter Yee, Markus Stenberg

Reference

[RFC4819][RFC9519]

Note

Registration requests should be sent to the mailing list described in 
[RFC9519]. If approved, designated experts should notify IANA within 
three weeks. For assistance, please contact iana@iana.org.

Available Formats

CSV

Attribute Name	Reference
comment	[RFC4819]
comment-language	[RFC4819]
command-override	[RFC4819]
subsystem	[RFC4819]
x11	[RFC4819]
shell	[RFC4819]
exec	[RFC4819]
agent	[RFC4819]
env	[RFC4819]
from	[RFC4819]
port-forward	[RFC4819]
reverse-forward	[RFC4819]

Publickey Subsystem Status Codes

Reference: [RFC4819]
Available Formats: CSV

Range	Registration Procedures
0-191	Standards Action
192-255	Reserved for Private Use

Value	Status Code	Reference
0	SSH_PUBLICKEY_SUCCESS	[RFC4819]
1	SSH_PUBLICKEY_ACCESS_DENIED	[RFC4819]
2	SSH_PUBLICKEY_STORAGE_EXCEEDED	[RFC4819]
3	SSH_PUBLICKEY_VERSION_NOT_SUPPORTED	[RFC4819]
4	SSH_PUBLICKEY_KEY_NOT_FOUND	[RFC4819]
5	SSH_PUBLICKEY_KEY_NOT_SUPPORTED	[RFC4819]
6	SSH_PUBLICKEY_KEY_ALREADY_PRESENT	[RFC4819]
7	SSH_PUBLICKEY_GENERAL_FAILURE	[RFC4819]
8	SSH_PUBLICKEY_REQUEST_NOT_SUPPORTED	[RFC4819]
9	SSH_PUBLICKEY_ATTRIBUTE_NOT_SUPPORTED	[RFC4819]
10-191	Standards Action
192-255	Reserved

Extension Names

Registration Procedure(s)

Expert Review

Expert(s)

Peter Yee, Markus Stenberg

Reference

[RFC8308][RFC9519]

Note

Names in the Extension Names table MUST follow the Conventions for 
Names defined in [RFC4250], Section 4.6.1.

Note

Registration requests should be sent to the mailing list described in 
[RFC9519]. If approved, designated experts should notify IANA within 
three weeks. For assistance, please contact iana@iana.org.

Available Formats

CSV

Extension Name	Reference	Note
server-sig-algs	[RFC8308]	Section 3.1
delay-compression	[RFC8308]	Section 3.2
no-flow-control	[RFC8308]	Section 3.3
elevation	[RFC8308]	Section 3.4