kdc/csr_authorizer.c

   1 /*
   2  * Copyright (c) 2019 Kungliga Tekniska Högskolan
   3  * (Royal Institute of Technology, Stockholm, Sweden).
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  *
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  *
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * 3. Neither the name of the Institute nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #include "kdc_locl.h"
  35 #include "csr_authorizer_plugin.h"
  36
  37 struct plctx {
  38     const char              *app;
  39     hx509_request           csr;
  40     krb5_const_principal    client;
  41     krb5_boolean            result;
  42 };
  43
  44 static krb5_error_code KRB5_LIB_CALL
  45 plcallback(krb5_context context, const void *plug, void *plugctx, void *userctx)
  46 {
  47     const krb5plugin_csr_authorizer_ftable *authorizer = plug;
  48     struct plctx *plctx = userctx;
  49
  50     return authorizer->authorize(plugctx, context, plctx->app, plctx->csr,
  51                                  plctx->client, &plctx->result);
  52 }
  53
  54 static const char *plugin_deps[] = { "krb5", NULL };
  55
  56 static struct heim_plugin_data csr_authorizer_data = {
  57     "kdc",
  58     KDC_CSR_AUTHORIZER,
  59     1,
  60     plugin_deps,
  61     krb5_get_instance
  62 };
  63
  64 /*
  65  * Invoke a plugin to validate a JWT/SAML/OIDC token and partially-evaluate
  66  * access control.
  67  */
  68 krb5_error_code
  69 kdc_authorize_csr(krb5_context context,
  70                   const char *app,
  71                   hx509_request csr,
  72                   krb5_const_principal client)
  73 {
  74     krb5_error_code ret;
  75     struct plctx ctx;
  76
  77     ctx.app = app;
  78     ctx.csr = csr;
  79     ctx.client = client;
  80     ctx.result = FALSE;
  81
  82     ret = _krb5_plugin_run_f(context, &csr_authorizer_data, 0, &ctx,
  83                              plcallback);
  84     if (ret)
  85         krb5_prepend_error_message(context, ret, "Authorization of requested "
  86                                    "certificate extensions failed");
  87     else if (!ctx.result)
  88         krb5_set_error_message(context, ret, "Authorization of requested "
  89                                "certificate extensions failed");
  90     return ret;
  91 }