.\" Copyright (C) The libssh2 project and its contributors.

.\" SPDX-License-Identifier: BSD-3-Clause

.TH libssh2_agent_sign 3 "1 Oct 2022" "libssh2" "libssh2"

.SH NAME

libssh2_agent_sign - sign data, with the help of ssh-agent

.SH SYNOPSIS

.nf

#include <libssh2.h>

int

libssh2_agent_sign(LIBSSH2_AGENT *agent,

struct libssh2_agent_publickey *identity,

unsigned char **sig,

size_t *s_len,

const unsigned char *data,

size_t d_len,

const char *method,

unsigned int method_len);

.fi

.SH DESCRIPTION

\fIagent\fP - ssh-agent handle as returned by

.BR libssh2_agent_init(3)

\fIidentity\fP - Public key to authenticate with, as returned by

.BR libssh2_agent_get_identity(3)

\fIsig\fP - A pointer to a buffer in which to place the signature. The caller

is responsible for freeing the signature with LIBSSH2_FREE.

\fIs_len\fP - A pointer to the length of the sig parameter.

\fIdata\fP - The data to sign.

\fId_len\fP - The length of the data parameter.

\fImethod\fP - A buffer indicating the signing method. This should match the

string at the start of identity->blob.

\fImethod_len\fP - The length of the method parameter.

Sign data using an ssh-agent. This function can be used in a callback

registered with libssh2_session_callback_set2(3) using

LIBSSH2_CALLBACK_AUTHAGENT_SIGN to sign an authentication challenge from a

server. However, the client is responsible for implementing the code that calls

this callback in response to a SSH2_AGENTC_SIGN_REQUEST message.

.SH RETURN VALUE

Returns 0 if succeeded, or a negative value for error.

.SH AVAILABILITY

Added in libssh2 1.11.0

.SH SEE ALSO

.BR libssh2_agent_init(3)

.BR libssh2_agent_get_identity(3)

.BR libssh2_agent_userauth(3)

.BR libssh2_session_callback_set2(3)