from __future__ import absolute_import

"""SSL callbacks

Copyright (c) 1999-2003 Ng Pheng Siong. All rights reserved."""

import sys

from M2Crypto import m2
from typing import Any, List  # noqa

__all__ = [
    'unknown_issuer',
    'ssl_verify_callback_stub',
    'ssl_verify_callback',
    'ssl_verify_callback_allow_unknown_ca',
    'ssl_info_callback',
]


def ssl_verify_callback_stub(
    ssl_ctx_ptr, x509_ptr, errnum, errdepth, ok
):
    # Deprecated
    return ok


unknown_issuer: List[int] = [
    m2.X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT,
    m2.X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY,
    m2.X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE,
    m2.X509_V_ERR_CERT_UNTRUSTED,
]


def ssl_verify_callback(
    ssl_ctx_ptr: bytes,
    x509_ptr: bytes,
    errnum: int,
    errdepth: int,
    ok: int,
) -> int:
    # Deprecated

    from M2Crypto.SSL.Context import Context

    ssl_ctx = Context.ctxmap()[int(ssl_ctx_ptr)]
    if errnum in unknown_issuer:
        if ssl_ctx.get_allow_unknown_ca():
            sys.stderr.write(
                "policy: %s: permitted...\n"
                % (m2.x509_get_verify_error(errnum))
            )
            sys.stderr.flush()
            ok = 1
    # CRL checking goes here...
    if ok:
        if ssl_ctx.get_verify_depth() >= errdepth:
            ok = 1
        else:
            ok = 0
    return ok


def ssl_verify_callback_allow_unknown_ca(ok: int, store: Any) -> int:
    errnum = store.get_error()
    if errnum in unknown_issuer:
        ok = 1
    return ok


# Cribbed from OpenSSL's apps/s_cb.c.
def ssl_info_callback(where: int, ret: int, ssl_ptr: bytes) -> None:

    w = where & ~m2.SSL_ST_MASK
    if w & m2.SSL_ST_CONNECT:
        state = "SSL connect"
    elif w & m2.SSL_ST_ACCEPT:
        state = "SSL accept"
    else:
        state = "SSL state unknown"

    if where & m2.SSL_CB_LOOP:
        sys.stderr.write(
            "LOOP: %s: %s\n" % (state, m2.ssl_get_state_v(ssl_ptr))
        )
        sys.stderr.flush()
        return

    if where & m2.SSL_CB_EXIT:
        if not ret:
            sys.stderr.write(
                "FAILED: %s: %s\n"
                % (state, m2.ssl_get_state_v(ssl_ptr))
            )
            sys.stderr.flush()
        else:
            sys.stderr.write(
                "INFO: %s: %s\n"
                % (state, m2.ssl_get_state_v(ssl_ptr))
            )
            sys.stderr.flush()
        return

    if where & m2.SSL_CB_ALERT:
        if where & m2.SSL_CB_READ:
            w = 'read'
        else:
            w = 'write'
        sys.stderr.write(
            "ALERT: %s: %s: %s\n"
            % (
                w,
                m2.ssl_get_alert_type_v(ret),
                m2.ssl_get_alert_desc_v(ret),
            )
        )
        sys.stderr.flush()
        return
