comp.h File Reference

RFC 4253 sec 6.2 compression: the negotiated stream, both directions. More...

#include "protocore_config.h"

Go to the source code of this file.

Classes
struct	CompNs
	Dispatch table. Addressed by offset, so the layout is asserted below. More...

Typedefs
typedef enum PROTO_ENUM_PACKED	SshCompAlg
	Negotiated compression algorithm, held per direction.

Enumerations
enum	PROTO_ENUM_PACKED { SSH_COMP_NONE = 0 , SSH_COMP_ZLIB = 1 , SSH_COMP_ZLIB_DELAYED = 2 }
	Negotiated compression algorithm, held per direction. More...

Functions
	PROTOCORE_NS_LAYOUT (CompNs, reset, set_s2c, on_newkeys, on_auth_success, s2c_active, s2c, set_c2s, c2s_active, c2s)
void	protocore_comp_reset (uint8_t *work, uint8_t i)
	Reset compression state for slot i (fresh connection). Does NOT run .
void	protocore_comp_set_s2c (uint8_t *work, uint8_t i, SshCompAlg alg)
	Record the s2c algorithm negotiated in KEXINIT (SshCompAlg).
void	protocore_comp_on_newkeys (uint8_t *work, uint8_t i)
	NEWKEYS completed: start the stream now if zlib was negotiated .
void	protocore_comp_on_auth_success (uint8_t *work, uint8_t i)
	SSH_MSG_USERAUTH_SUCCESS sent: start the stream if .
proto_bool	protocore_comp_s2c_active (uint8_t *work, uint8_t i)
	True once the s2c stream is active and outbound payloads must be .
int	protocore_comp_s2c (uint8_t *work, uint8_t i, const uint8_t *src, size_t src_len, uint8_t *dst, size_t dst_cap, size_t *out_len)
	Compress one outbound payload, continuing the session's zlib stream.
void	protocore_comp_set_c2s (uint8_t *work, uint8_t i, SshCompAlg alg)
	Record the client-to-server algorithm negotiated in KEXINIT .
proto_bool	protocore_comp_c2s_active (uint8_t *work, uint8_t i)
	True once the c2s stream is active and inbound payloads must be .
int	protocore_comp_c2s (uint8_t *work, uint8_t i, const uint8_t *src, size_t src_len, uint8_t *dst, size_t dst_cap, size_t *out_len)
	Decompress one inbound payload, continuing the session's .
uint8_t *	protocore_ssh_comp_span (void)
	The bytes every entry here runs out of: one compressor per SSH connection.

Variables
PROTOCORE_NS CompNs Comp	PROTOCORE_UNUSED
	Module namespace.

Detailed Description

RFC 4253 sec 6.2 compression: the negotiated stream, both directions.

work is bytes the CALLER holds. This module reads none of them: it carries nothing between calls, so there is no state to keep and nothing to wipe. The parameter is there so a caller drives every namespace the same way.

Definition in file comp.h.

Typedef Documentation

SshCompAlg

typedef enum PROTO_ENUM_PACKED SshCompAlg

Negotiated compression algorithm, held per direction.

Enumeration Type Documentation

PROTO_ENUM_PACKED

enum PROTO_ENUM_PACKED

Negotiated compression algorithm, held per direction.

Enumerator
SSH_COMP_NONE	no compression
SSH_COMP_ZLIB	"zlib" (RFC 4253) - starts right after NEWKEYS
SSH_COMP_ZLIB_DELAYED	"zlib@openssh.com" - starts after SSH_MSG_USERAUTH_SUCCESS

Definition at line 25 of file comp.h.

Function Documentation

PROTOCORE_NS_LAYOUT()

PROTOCORE_NS_LAYOUT	(	CompNs	,
		reset	,
		set_s2c	,
		on_newkeys	,
		on_auth_success	,
		s2c_active	,
		s2c	,
		set_c2s	,
		c2s_active	,
		c2s
	)

protocore_comp_reset()

void protocore_comp_reset	(	uint8_t *	work,
		uint8_t	i
	)

Reset compression state for slot i (fresh connection). Does NOT run .

Parameters

work	PROTOCORE_COMP_BORROW bytes the caller took. Not held past the call.
i	I

protocore_comp_set_s2c()

void protocore_comp_set_s2c	(	uint8_t *	work,
		uint8_t	i,
		SshCompAlg	alg
	)

Record the s2c algorithm negotiated in KEXINIT (SshCompAlg).

Parameters

work	PROTOCORE_COMP_BORROW bytes the caller took. Not held past the call.
i	I
alg	Alg

protocore_comp_on_newkeys()

void protocore_comp_on_newkeys	(	uint8_t *	work,
		uint8_t	i
	)

NEWKEYS completed: start the stream now if zlib was negotiated .

Parameters

work	PROTOCORE_COMP_BORROW bytes the caller took. Not held past the call.
i	I

protocore_comp_on_auth_success()

void protocore_comp_on_auth_success	(	uint8_t *	work,
		uint8_t	i
	)

SSH_MSG_USERAUTH_SUCCESS sent: start the stream if .

Parameters

work	PROTOCORE_COMP_BORROW bytes the caller took. Not held past the call.
i	I

protocore_comp_s2c_active()

proto_bool protocore_comp_s2c_active	(	uint8_t *	work,
		uint8_t	i
	)

True once the s2c stream is active and outbound payloads must be .

Parameters

work	PROTOCORE_COMP_BORROW bytes the caller took. Not held past the call.
i	I

Returns

PROTO_TRUE on success.

protocore_comp_s2c()

int protocore_comp_s2c	(	uint8_t *	work,
		uint8_t	i,
		const uint8_t *	src,
		size_t	src_len,
		uint8_t *	dst,
		size_t	dst_cap,
		size_t *	out_len
	)

Compress one outbound payload, continuing the session's zlib stream.

Parameters

work	PROTOCORE_COMP_BORROW bytes the caller took. Not held past the call.
i	I
src	Src
src_len	Src len
dst	Dst
dst_cap	Dst cap
out_len	Out len

Returns

The int.

protocore_comp_set_c2s()

void protocore_comp_set_c2s	(	uint8_t *	work,
		uint8_t	i,
		SshCompAlg	alg
	)

Record the client-to-server algorithm negotiated in KEXINIT .

Parameters

work	PROTOCORE_COMP_BORROW bytes the caller took. Not held past the call.
i	I
alg	Alg

protocore_comp_c2s_active()

proto_bool protocore_comp_c2s_active	(	uint8_t *	work,
		uint8_t	i
	)

True once the c2s stream is active and inbound payloads must be .

Parameters

work	PROTOCORE_COMP_BORROW bytes the caller took. Not held past the call.
i	I

Returns

PROTO_TRUE on success.

protocore_comp_c2s()

int protocore_comp_c2s	(	uint8_t *	work,
		uint8_t	i,
		const uint8_t *	src,
		size_t	src_len,
		uint8_t *	dst,
		size_t	dst_cap,
		size_t *	out_len
	)

Decompress one inbound payload, continuing the session's .

Parameters

work	PROTOCORE_COMP_BORROW bytes the caller took. Not held past the call.
i	I
src	Src
src_len	Src len
dst	Dst
dst_cap	Dst cap
out_len	Out len

Returns

The int.

protocore_ssh_comp_span()

uint8_t * protocore_ssh_comp_span

(

void

)

The bytes every entry here runs out of: one compressor per SSH connection.

Stated beside the namespace rather than on it: an entry takes a borrow, and this is where that borrow comes from. The transport and the server both drive the same connection's streams, so the bytes belong to this module rather than to either caller. Taken once from the end of the plaintext pool, which no mark and no release walks, because a zlib@.nosp@m.open.nosp@m.ssh.c.nosp@m.om stream takes its window over from one packet to the next.

Returns

the span.

Variable Documentation

PROTOCORE_UNUSED

PROTOCORE_NS CompNs Comp PROTOCORE_UNUSED

Initial value:

= {.reset = protocore_comp_reset,
                                             .set_s2c = protocore_comp_set_s2c,
                                             .on_newkeys = protocore_comp_on_newkeys,
                                             .on_auth_success = protocore_comp_on_auth_success,
                                             .s2c_active = protocore_comp_s2c_active,
                                             .s2c = protocore_comp_s2c,
                                             .set_c2s = protocore_comp_set_c2s,
                                             .c2s_active = protocore_comp_c2s_active,
                                             .c2s = protocore_comp_c2s}

Module namespace.

Definition at line 134 of file comp.h.