libssh2_knownhost_checkp.3

.\" Copyright (C) Daniel Stenberg
.\" SPDX-License-Identifier: BSD-3-Clause
.TH libssh2_knownhost_checkp 3 "1 May 2010" "libssh2" "libssh2"
.SH NAME
libssh2_knownhost_checkp - check a host+key against the list of known hosts
.SH SYNOPSIS
.nf
#include <libssh2.h>

int
libssh2_knownhost_checkp(LIBSSH2_KNOWNHOSTS *hosts,
                         const char *host, int port,
                         const char *key, size_t keylen,
                         int typemask,
                         struct libssh2_knownhost **knownhost);
.fi
.SH DESCRIPTION
Checks a host and its associated key against the collection of known hosts,
and returns info back about the (partially) matched entry.

\fIhost\fP is a pointer the host name in plain text. The host name can be the
IP numerical address of the host or the full name.

\fIport\fP is the port number used by the host (or a negative number
to check the generic host). If the port number is given, libssh2 will
check the key for the specific host + port number combination in
addition to the plain host name only check.

\fIkey\fP is a pointer to the key for the given host.

\fIkeylen\fP is the total size in bytes of the key pointed to by the \fIkey\fP
argument

\fItypemask\fP is a bitmask that specifies format and info about the data
passed to this function. Specifically, it details what format the host name is,
what format the key is and what key type it is.

The host name is given as one of the following types:
LIBSSH2_KNOWNHOST_TYPE_PLAIN or LIBSSH2_KNOWNHOST_TYPE_CUSTOM.

The key is encoded using one of the following encodings:
LIBSSH2_KNOWNHOST_KEYENC_RAW or LIBSSH2_KNOWNHOST_KEYENC_BASE64.

\fIknownhost\fP if set to non-NULL, it must be a pointer to a 'struct
libssh2_knownhost' pointer that gets filled in to point to info about a known
host that matches or partially matches.
.SH RETURN VALUE
\fIlibssh2_knownhost_check(3)\fP returns info about how well the provided
host + key pair matched one of the entries in the list of known hosts.

LIBSSH2_KNOWNHOST_CHECK_FAILURE - something prevented the check to be made

LIBSSH2_KNOWNHOST_CHECK_NOTFOUND - no host match was found

LIBSSH2_KNOWNHOST_CHECK_MATCH - hosts and keys match.

LIBSSH2_KNOWNHOST_CHECK_MISMATCH - host was found, but the keys did not match!
.SH AVAILABILITY
Added in libssh2 1.2.6
.SH EXAMPLE
See the ssh2_exec.c example as provided in the tarball.
.SH SEE ALSO
.BR libssh2_knownhost_init(3)
.BR libssh2_knownhost_free(3)
.BR libssh2_knownhost_add(3)