# gevent

# `gevent._ssl2` – SSL wrapper for socket objects on Python 2.7.8 and below

SSL wrapper for socket objects on Python 2.7.8 and below.

For the documentation, refer to `ssl` module manual.

This module implements cooperative SSL socket wrappers.

Deprecated since version 1.3: This module is not secure. Support for Python versions with only this level of SSL will be dropped in gevent 1.4.

CertificateError

  alias of `ssl.SSLCertVerificationError`

exception SSLCertVerificationError

  Bases: `ssl.SSLError`, `ValueError`

  A certificate could not be verified.

exception SSLEOFError

  Bases: `ssl.SSLError`

  SSL/TLS connection terminated abruptly.

exception SSLError

  Bases: `OSError`

  An error occurred in the SSL implementation.

exception SSLSyscallError

  Bases: `ssl.SSLError`

  System error when attempting SSL operation.

exception SSLWantReadError

  Bases: `ssl.SSLError`

  Non-blocking SSL socket needs to read more data before the requested operation can be completed.

exception SSLWantWriteError

  Bases: `ssl.SSLError`

  Non-blocking SSL socket needs to write more data before the requested operation can be completed.

exception SSLZeroReturnError

  Bases: `ssl.SSLError`

  SSL/TLS session closed cleanly.

socket_error

  alias of `OSError`

class AlertDescription(value)

  Bases: `enum.IntEnum`

  An enumeration.

class DefaultVerifyPaths(cafile, capath, openssl_cafile_env, openssl_cafile, openssl_capath_env, openssl_capath)

  Bases: `tuple`

  Create new instance of DefaultVerifyPaths(cafile, capath, openssl_cafile_env, openssl_cafile, openssl_capath_env, openssl_capath)

  cafile

    Alias for field number 0

  capath

    Alias for field number 1

  openssl_cafile

    Alias for field number 3

  openssl_cafile_env

    Alias for field number 2

  openssl_capath

    Alias for field number 5

  openssl_capath_env

    Alias for field number 4

class Options(value)

  Bases: `enum.IntFlag`

  An enumeration.

class Purpose(value)

  Bases: `ssl._ASN1Object`, `enum.Enum`

  SSLContext purpose flags with X509v3 Extended Key Usage objects

  Create new instance of _ASN1Object(nid, shortname, longname, oid)

class SSLContext(protocol=None, *args, **kwargs)

  Bases: `_ssl._SSLContext`

  An SSLContext holds various SSL-related configuration options and data, such as certificates and possibly a private key.

  sslobject_class

    alias of `ssl.SSLObject`

  sslsocket_class

    alias of `ssl.SSLSocket`

class SSLErrorNumber(value)

  Bases: `enum.IntEnum`

  An enumeration.

class SSLObject(*args, **kwargs)

  Bases: `object`

  This class implements an interface on top of a low-level SSL object as implemented by OpenSSL. This object captures the state of an SSL connection but does not provide any network IO itself. IO needs to be performed through separate “BIO” objects which are OpenSSL’s IO abstraction layer.

  This class does not have a public constructor. Instances are returned by `SSLContext.wrap_bio`. This class is typically used by framework authors that want to implement asynchronous IO for SSL through memory buffers.

  When compared to `SSLSocket`, this object lacks the following features:

  > - Any form of network IO, including methods such as `recv` and `send`.

  > - The `do_handshake_on_connect` and `suppress_ragged_eofs` machinery.

  cipher()

    Return the currently selected cipher as a 3-tuple `(name, ssl_version, secret_bits)`.

  compression()

    Return the current compression algorithm in use, or `None` if compression was not negotiated or not supported by one of the peers.

  do_handshake()

    Start the SSL/TLS handshake.

  get_channel_binding(cb_type='tls-unique')

    Get channel binding data for current connection. Raise ValueError if the requested `cb_type` is not supported. Return bytes of the data or None if the data is not available (e.g. before the handshake).

  getpeercert(binary_form=False)

    Returns a formatted version of the data in the certificate provided by the other end of the SSL channel.

    Return None if no certificate was provided, {} if a certificate was provided, but not validated.

  pending()

    Return the number of bytes that can be read immediately.

  read(len=1024, buffer=None)

    Read up to ‘len’ bytes from the SSL object and return them.

    If ‘buffer’ is provided, read into this buffer and return the number of bytes read.

  selected_alpn_protocol()

    Return the currently selected ALPN protocol as a string, or `None` if a next protocol was not negotiated or if ALPN is not supported by one of the peers.

  selected_npn_protocol()

    Return the currently selected NPN protocol as a string, or `None` if a next protocol was not negotiated or if NPN is not supported by one of the peers.

  shared_ciphers()

    Return a list of ciphers shared by the client during the handshake or None if this is not a valid server connection.

  unwrap()

    Start the SSL shutdown handshake.

  version()

    Return a string identifying the protocol version used by the current SSL channel.

  write(data)

    Write ‘data’ to the SSL object and return the number of bytes written.

    The ‘data’ argument must support the buffer interface.

  property context

    The SSLContext that is currently in use.

  property server_hostname

    The currently set server hostname (for SNI), or `None` if no server hostname is set.

  property server_side

    Whether this is a server-side socket.

  property session

    The SSLSession for client socket.

  property session_reused

    Was the client session reused during handshake

class SSLSocket(sock, keyfile=None, certfile=None, server_side=False, cert_reqs=VerifyMode.CERT_NONE, ssl_version=_SSLMethod.PROTOCOL_TLS, ca_certs=None, do_handshake_on_connect=True, suppress_ragged_eofs=True, ciphers=None)

  Bases: `gevent._socket2.socket`

  gevent ssl.SSLSocket for Pythons < 2.7.9.

  accept()

    Accepts a new connection from a remote client, and returns a tuple containing that new connection wrapped with a server-side SSL channel, and the address of the remote client.

  connect(addr)

    Connects to remote ADDR, and then wraps the connection in an SSL channel.

  do_handshake()

    Perform a TLS/SSL handshake.

  getpeercert(binary_form=False)

    Returns a formatted version of the data in the certificate provided by the other end of the SSL channel. Return None if no certificate was provided, {} if a certificate was provided, but not validated.

  makefile(mode='r', bufsize=- 1)

    Make and return a file-like object that works with the SSL connection. Just use the code from the socket module.

  read(len=1024)

    Read up to LEN bytes and return them. Return zero-length string on EOF.

  recv(buffersize[, flags]) → data

    Receive up to buffersize bytes from the socket. For the optional flags argument, see the Unix manual. When no data is available, block until at least one byte is available or until the remote end is closed. When the remote end is closed and all data is read, return the empty string.

  recv_into(buffer[, nbytes[, flags]]) → nbytes_read

    A version of recv() that stores its data into a buffer rather than creating a new string. Receive up to buffersize bytes from the socket. If buffersize is not specified (or 0), receive up to the size available in the given buffer.

    See recv() for documentation about the flags.

  recvfrom(buffersize[, flags]) -> (data, address info)

    Like recv(buffersize, flags) but also return the sender’s address info.

  recvfrom_into(buffer[, nbytes[, flags]]) -> (nbytes, address info)

    Like recv_into(buffer[, nbytes[, flags]]) but also return the sender’s address info.

  send(data[, flags]) → count

    Send a data string to the socket. For the optional flags argument, see the Unix manual. Return the number of bytes sent; this may be less than len(data) if the network is busy.

  sendall(data[, flags])

    Send a data string to the socket. For the optional flags argument, see the Unix manual. This calls send() repeatedly until all data is sent. If an error occurs, it’s impossible to tell how much data has been sent.

  sendto(data, [flags, ]address) → count

    Like send(data, flags) but allows specifying the destination address. For IP sockets, the address is a pair (hostaddr, port).

  shutdown(flag)

    Shut down the reading side of the socket (flag == SHUT_RD), the writing side of the socket (flag == SHUT_WR), or both ends (flag == SHUT_RDWR).

  write(data)

    Write DATA to the underlying SSL channel. Returns number of bytes of DATA actually transmitted.

class TLSVersion(value)

  Bases: `enum.IntEnum`

  An enumeration.

class VerifyFlags(value)

  Bases: `enum.IntFlag`

  An enumeration.

class VerifyMode(value)

  Bases: `enum.IntEnum`

  An enumeration.

DER_cert_to_PEM_cert(der_cert_bytes)

  Takes a certificate in binary DER format and returns the PEM version of it as a string.

PEM_cert_to_DER_cert(pem_cert_string)

  Takes a certificate in ASCII PEM format and returns the DER-encoded version of it as a byte sequence

RAND_add(string, entropy, /)

  Mix string into the OpenSSL PRNG state.

  entropy (a float) is a lower bound on the entropy contained in string. See RFC 4086.

RAND_bytes(n, /)

  Generate n cryptographically strong pseudo-random bytes.

RAND_pseudo_bytes(n, /)

  Generate n pseudo-random bytes.

  Return a pair (bytes, is_cryptographic). is_cryptographic is True if the bytes generated are cryptographically strong.

RAND_status()

  Returns True if the OpenSSL PRNG has been seeded with enough data and False if not.

  It is necessary to seed the PRNG with RAND_add() on some platforms before using the ssl() function.

cert_time_to_seconds(cert_time)

  Return the time in seconds since the Epoch, given the timestring representing the “notBefore” or “notAfter” date from a certificate in `"%b %d %H:%M:%S %Y %Z"` strptime format (C locale).

  “notBefore” or “notAfter” dates must use UTC (RFC 5280).

  Month is one of: Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec UTC should be specified as GMT (see ASN1_TIME_print())

create_connection(address, timeout=<object object>, source_address=None)

  Connect to address and return the socket object.

  Convenience function. Connect to address (a 2-tuple `(host, port)`) and return the socket object. Passing the optional timeout parameter will set the timeout on the socket instance before attempting to connect. If no timeout is supplied, the global default timeout setting returned by `getdefaulttimeout()` is used. If source_address is set it must be a tuple of (host, port) for the socket to bind as a source address before making the connection. A host of ‘’ or port 0 tells the OS to use the default.

create_default_context(purpose=Purpose.SERVER_AUTH, *, cafile=None, capath=None, cadata=None)

  Create a SSLContext object with default settings.

  NOTE: The protocol and settings may change anytime without prior

    deprecation. The values represent a fair balance between maximum compatibility and security.

get_default_verify_paths()

  Return paths to default cafile and capath.

get_server_certificate(addr, ssl_version=_SSLMethod.PROTOCOL_TLS, ca_certs=None)

  Retrieve the certificate from the server at the specified address, and return it as a PEM-encoded string. If ‘ca_certs’ is specified, validate the server cert against it. If ‘ssl_version’ is specified, use it in the connection attempt.

match_hostname(cert, hostname)

  Verify that cert (in decoded format as returned by SSLSocket.getpeercert()) matches the hostname. RFC 2818 and RFC 6125 rules are followed.

  The function matches IP addresses rather than dNSNames if hostname is a valid ipaddress string. IPv4 addresses are supported on all platforms. IPv6 addresses are supported on platforms with IPv6 support (AF_INET6 and inet_pton).

  CertificateError is raised on failure. On success, the function returns nothing.

sslwrap_simple(sock, keyfile=None, certfile=None)

  A replacement for the old socket.ssl function. Designed for compatibility with Python 2.5 and earlier. Will disappear in Python 3.0.

wrap_socket(sock, keyfile=None, certfile=None, server_side=False, cert_reqs=VerifyMode.CERT_NONE, ssl_version=_SSLMethod.PROTOCOL_TLS, ca_certs=None, do_handshake_on_connect=True, suppress_ragged_eofs=True, ciphers=None)

  Create a new `SSLSocket` instance.

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