Host keys / known_hosts
files¶
- class paramiko.hostkeys.HostKeys(filename=None)¶
Representation of an OpenSSH-style “known hosts” file. Host keys can be read from one or more files, and then individual hosts can be looked up to verify server keys during SSH negotiation.
A
HostKeys
object can be treated like a dict; any dict lookup is equivalent to callinglookup
.New in version 1.5.3.
- __init__(filename=None)¶
Create a new HostKeys object, optionally loading keys from an OpenSSH style host-key file.
- Parameters
filename (str) – filename to load host keys from, or
None
- add(hostname, keytype, key)¶
Add a host key entry to the table. Any existing entry for a
(hostname, keytype)
pair will be replaced.- Parameters
hostname (str) – the hostname (or IP) to add
keytype (str) – key type (
"ssh-rsa"
or"ssh-dss"
)key (PKey) – the key to add
- load(filename)¶
Read a file of known SSH host keys, in the format used by OpenSSH. This type of file unfortunately doesn’t exist on Windows, but on posix, it will usually be stored in
os.path.expanduser("~/.ssh/known_hosts")
.If this method is called multiple times, the host keys are merged, not cleared. So multiple calls to
load
will just calladd
, replacing any existing entries and adding new ones.- Parameters
filename (str) – name of the file to read host keys from
- Raises
IOError
– if there was an error reading the file
- save(filename)¶
Save host keys into a file, in the format used by OpenSSH. The order of keys in the file will be preserved when possible (if these keys were loaded from a file originally). The single exception is that combined lines will be split into individual key lines, which is arguably a bug.
- Parameters
filename (str) – name of the file to write
- Raises
IOError
– if there was an error writing the file
New in version 1.6.1.
- lookup(hostname)¶
Find a hostkey entry for a given hostname or IP. If no entry is found,
None
is returned. Otherwise a dictionary of keytype to key is returned. The keytype will be either"ssh-rsa"
or"ssh-dss"
.- Parameters
hostname (str) – the hostname (or IP) to lookup
- Returns
dict of
str
->PKey
keys associated with this host (orNone
)
- check(hostname, key)¶
Return True if the given key is associated with the given hostname in this dictionary.
- Parameters
hostname (str) – hostname (or IP) of the SSH server
key (PKey) – the key to check
- Returns
True
if the key is associated with the hostname; elseFalse
- clear()¶
Remove all host keys from the dictionary.
- keys() a set-like object providing a view on D's keys ¶
- values() an object providing a view on D's values ¶
- static hash_host(hostname, salt=None)¶
Return a “hashed” form of the hostname, as used by OpenSSH when storing hashed hostnames in the known_hosts file.
- Parameters
hostname (str) – the hostname to hash
salt (str) – optional salt to use when hashing (must be 20 bytes long)
- Returns
the hashed hostname as a
str
- __weakref__¶
list of weak references to the object (if defined)
- exception paramiko.hostkeys.InvalidHostKey(line, exc)¶
- __init__(line, exc)¶
- __weakref__¶
list of weak references to the object (if defined)
- class paramiko.hostkeys.HostKeyEntry(hostnames=None, key=None)¶
Representation of a line in an OpenSSH-style “known hosts” file.
- __init__(hostnames=None, key=None)¶
- classmethod from_line(line, lineno=None)¶
Parses the given line of text to find the names for the host, the type of key, and the key data. The line is expected to be in the format used by the OpenSSH known_hosts file. Fields are separated by a single space or tab.
Lines are expected to not have leading or trailing whitespace. We don’t bother to check for comments or empty lines. All of that should be taken care of before sending the line to us.
- Parameters
line (str) – a line from an OpenSSH known_hosts file
- to_line()¶
Returns a string in OpenSSH known_hosts file format, or None if the object is not in a valid state. A trailing newline is included.
- __repr__()¶
Return repr(self).
- __weakref__¶
list of weak references to the object (if defined)