preauth/pkinit/pkinit_srv.c

/*
 * COPYRIGHT (C) 2006,2007
 * THE REGENTS OF THE UNIVERSITY OF MICHIGAN
 * ALL RIGHTS RESERVED
 *
 * Permission is granted to use, copy, create derivative works
 * and redistribute this software and such derivative works
 * for any purpose, so long as the name of The University of
 * Michigan is not used in any advertising or publicity
 * pertaining to the use of distribution of this software
 * without specific, written prior authorization.  If the
 * above copyright notice or any other identification of the
 * University of Michigan is included in any copy of any
 * portion of this software, then the disclaimer below must
 * also be included.
 *
 * THIS SOFTWARE IS PROVIDED AS IS, WITHOUT REPRESENTATION
 * FROM THE UNIVERSITY OF MICHIGAN AS TO ITS FITNESS FOR ANY
 * PURPOSE, AND WITHOUT WARRANTY BY THE UNIVERSITY OF
 * MICHIGAN OF ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING
 * WITHOUT LIMITATION THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE
 * REGENTS OF THE UNIVERSITY OF MICHIGAN SHALL NOT BE LIABLE
 * FOR ANY DAMAGES, INCLUDING SPECIAL, INDIRECT, INCIDENTAL, OR
 * CONSEQUENTIAL DAMAGES, WITH RESPECT TO ANY CLAIM ARISING
 * OUT OF OR IN CONNECTION WITH THE USE OF THE SOFTWARE, EVEN
 * IF IT HAS BEEN OR IS HEREAFTER ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGES.
 */

#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>

#include "pkinit.h"

static krb5_error_code
pkinit_server_get_edata(krb5_context context,
            krb5_kdc_req * request,
            struct _krb5_db_entry_new * client,
            struct _krb5_db_entry_new * server,
            preauth_get_entry_data_proc server_get_entry_data,
            void *pa_plugin_context,
            krb5_pa_data * data);

static krb5_error_code
pkinit_server_verify_padata(krb5_context context,
                struct _krb5_db_entry_new * client,
                krb5_data *req_pkt,
                krb5_kdc_req * request,
                krb5_enc_tkt_part * enc_tkt_reply,
                krb5_pa_data * data,
                preauth_get_entry_data_proc server_get_entry_data,
                void *pa_plugin_context,
                void **pa_request_context,
                krb5_data **e_data,
                krb5_authdata ***authz_data);

static krb5_error_code
pkinit_server_return_padata(krb5_context context,
                krb5_pa_data * padata,
                struct _krb5_db_entry_new * client,
                krb5_data *req_pkt,
                krb5_kdc_req * request,
                krb5_kdc_rep * reply,
                struct _krb5_key_data * client_key,
                krb5_keyblock * encrypting_key,
                krb5_pa_data ** send_pa,
                preauth_get_entry_data_proc server_get_entry_data,
                void *pa_plugin_context,
                void **pa_request_context);

static int pkinit_server_get_flags
    (krb5_context kcontext, krb5_preauthtype patype);

static krb5_error_code pkinit_init_kdc_req_context
    (krb5_context, void **blob);

static void pkinit_fini_kdc_req_context
    (krb5_context context, void *blob);

static int pkinit_server_plugin_init_realm
    (krb5_context context, const char *realmname,
     pkinit_kdc_context *pplgctx);

static void pkinit_server_plugin_fini_realm
    (krb5_context context, pkinit_kdc_context plgctx);

static int pkinit_server_plugin_init
    (krb5_context context, void **blob, const char **realmnames);

static void pkinit_server_plugin_fini
    (krb5_context context, void *blob);

static pkinit_kdc_context pkinit_find_realm_context
    (krb5_context context, void *pa_plugin_context, krb5_principal princ);

static krb5_error_code
pkinit_create_edata(krb5_context context,
            pkinit_plg_crypto_context plg_cryptoctx,
            pkinit_req_crypto_context req_cryptoctx,
            pkinit_identity_crypto_context id_cryptoctx,
            pkinit_plg_opts *opts,
            krb5_error_code err_code,
            krb5_data **e_data)
{
    krb5_error_code retval = KRB5KRB_ERR_GENERIC;

    pkiDebug("pkinit_create_edata: creating edata for error %d (%s)\n",
         err_code, error_message(err_code));
    switch(err_code) {
    case KRB5KDC_ERR_CANT_VERIFY_CERTIFICATE:
        retval = pkinit_create_td_trusted_certifiers(context,
        plg_cryptoctx, req_cryptoctx, id_cryptoctx, e_data);
        break;
    case KRB5KDC_ERR_DH_KEY_PARAMETERS_NOT_ACCEPTED:
        retval = pkinit_create_td_dh_parameters(context, plg_cryptoctx,
        req_cryptoctx, id_cryptoctx, opts, e_data);
        break;
    case KRB5KDC_ERR_INVALID_CERTIFICATE:
    case KRB5KDC_ERR_REVOKED_CERTIFICATE:
        retval = pkinit_create_td_invalid_certificate(context,
        plg_cryptoctx, req_cryptoctx, id_cryptoctx, e_data);
        break;
    default:
        pkiDebug("no edata needed for error %d (%s)\n",
             err_code, error_message(err_code));
        retval = 0;
        goto cleanup;
    }

cleanup:

    return retval;
}

/* ARGSUSED */
static krb5_error_code
pkinit_server_get_edata(krb5_context context,
            krb5_kdc_req * request,
            struct _krb5_db_entry_new * client,
            struct _krb5_db_entry_new * server,
            preauth_get_entry_data_proc server_get_entry_data,
            void *pa_plugin_context,
            krb5_pa_data * data)
{
    krb5_error_code retval = 0;
    pkinit_kdc_context plgctx = NULL;

    pkiDebug("pkinit_server_get_edata: entered!\n");

    /*
     * If we don't have a realm context for the given realm,
     * don't tell the client that we support pkinit!
     */
    plgctx = pkinit_find_realm_context(context, pa_plugin_context,
                       request->server);
    if (plgctx == NULL)
    retval = EINVAL;

    return retval;
}

static krb5_error_code
verify_client_san(krb5_context context,
          pkinit_kdc_context plgctx,
          pkinit_kdc_req_context reqctx,
          krb5_principal client,
          int *valid_san)
{
    krb5_error_code retval;
    krb5_principal *princs = NULL;
    krb5_principal *upns = NULL;
    int i;
#ifdef DEBUG_SAN_INFO
    char *client_string = NULL, *san_string;
#endif

    retval = crypto_retrieve_cert_sans(context, plgctx->cryptoctx,
                       reqctx->cryptoctx, plgctx->idctx,
                       &princs,
                       plgctx->opts->allow_upn ? &upns : NULL,
                       NULL);
    if (retval) {
    pkiDebug("%s: error from retrieve_certificate_sans()\n", __FUNCTION__);
    retval = KRB5KDC_ERR_CLIENT_NAME_MISMATCH;
    goto out;
    }
    /* XXX Verify this is consistent with client side XXX */
#if 0
    retval = call_san_checking_plugins(context, plgctx, reqctx, princs,
                       upns, NULL, &plugin_decision, &ignore);
    pkiDebug("%s: call_san_checking_plugins() returned retval %d\n",
         __FUNCTION__);
    if (retval) {
    retval = KRB5KDC_ERR_CLIENT_NAME_MISMATCH;
    goto cleanup;
    }
    pkiDebug("%s: call_san_checking_plugins() returned decision %d\n",
         __FUNCTION__, plugin_decision);
    if (plugin_decision != NO_DECISION) {
    retval = plugin_decision;
    goto out;
    }
#endif

#ifdef DEBUG_SAN_INFO
    krb5_unparse_name(context, client, &client_string);
#endif
    pkiDebug("%s: Checking pkinit sans\n", __FUNCTION__);
    for (i = 0; princs != NULL && princs[i] != NULL; i++) {
#ifdef DEBUG_SAN_INFO
    krb5_unparse_name(context, princs[i], &san_string);
    pkiDebug("%s: Comparing client '%s' to pkinit san value '%s'\n",
         __FUNCTION__, client_string, san_string);
    krb5_free_unparsed_name(context, san_string);
#endif
    if (krb5_principal_compare(context, princs[i], client)) {
        pkiDebug("%s: pkinit san match found\n", __FUNCTION__);
        *valid_san = 1;
        retval = 0;
        goto out;
    }
    }
    pkiDebug("%s: no pkinit san match found\n", __FUNCTION__);
    /*
     * XXX if cert has names but none match, should we
     * be returning KRB5KDC_ERR_CLIENT_NAME_MISMATCH here?
     */

    if (upns == NULL) {
    pkiDebug("%s: no upn sans (or we wouldn't accept them anyway)\n",
         __FUNCTION__);
    retval = KRB5KDC_ERR_CLIENT_NAME_MISMATCH;
    goto out;
    }

    pkiDebug("%s: Checking upn sans\n", __FUNCTION__);
    for (i = 0; upns[i] != NULL; i++) {
#ifdef DEBUG_SAN_INFO
    krb5_unparse_name(context, upns[i], &san_string);
    pkiDebug("%s: Comparing client '%s' to upn san value '%s'\n",
         __FUNCTION__, client_string, san_string);
    krb5_free_unparsed_name(context, san_string);
#endif
    if (krb5_principal_compare(context, upns[i], client)) {
        pkiDebug("%s: upn san match found\n", __FUNCTION__);
        *valid_san = 1;
        retval = 0;
        goto out;
    }
    }
    pkiDebug("%s: no upn san match found\n", __FUNCTION__);

    /* We found no match */
    if (princs != NULL || upns != NULL) {
    *valid_san = 0;
    /* XXX ??? If there was one or more name in the cert, but
     * none matched the client name, then return mismatch? */
    retval = KRB5KDC_ERR_CLIENT_NAME_MISMATCH;
    }
    retval = 0;

out:
    if (princs != NULL) {
    for (i = 0; princs[i] != NULL; i++)
        krb5_free_principal(context, princs[i]);
    free(princs);
    }
    if (upns != NULL) {
    for (i = 0; upns[i] != NULL; i++)
        krb5_free_principal(context, upns[i]);
    free(upns);
    }
#ifdef DEBUG_SAN_INFO
    if (client_string != NULL)
    krb5_free_unparsed_name(context, client_string);
#endif
    pkiDebug("%s: returning retval %d, valid_san %d\n",
         __FUNCTION__, retval, *valid_san);
    return retval;
}

static krb5_error_code
verify_client_eku(krb5_context context,
          pkinit_kdc_context plgctx,
          pkinit_kdc_req_context reqctx,
          int *eku_accepted)
{
    krb5_error_code retval;

    *eku_accepted = 0;

    if (plgctx->opts->require_eku == 0) {
    pkiDebug("%s: configuration requests no EKU checking\n", __FUNCTION__);
    *eku_accepted = 1;
    retval = 0;
    goto out;
    }

    retval = crypto_check_cert_eku(context, plgctx->cryptoctx,
                   reqctx->cryptoctx, plgctx->idctx,
                   0, /* kdc cert */
                   plgctx->opts->accept_secondary_eku,
                   eku_accepted);
    if (retval) {
    pkiDebug("%s: Error from crypto_check_cert_eku %d (%s)\n",
         __FUNCTION__, retval, error_message(retval));
    goto out;
    }

out:
    pkiDebug("%s: returning retval %d, eku_accepted %d\n",
         __FUNCTION__, retval, *eku_accepted);
    return retval;
}

/* ARGSUSED */
static krb5_error_code
pkinit_server_verify_padata(krb5_context context,
                struct _krb5_db_entry_new * client,
                krb5_data *req_pkt,
                krb5_kdc_req * request,
                krb5_enc_tkt_part * enc_tkt_reply,
                krb5_pa_data * data,
                preauth_get_entry_data_proc server_get_entry_data,
                void *pa_plugin_context,
                void **pa_request_context,
                krb5_data **e_data,
                krb5_authdata ***authz_data)
{
    krb5_error_code retval = 0;
    krb5_octet_data authp_data = {0, 0, NULL}, krb5_authz = {0, 0, NULL};
    krb5_data *encoded_pkinit_authz_data = NULL;
    krb5_pa_pk_as_req *reqp = NULL;
    krb5_pa_pk_as_req_draft9 *reqp9 = NULL;
    krb5_auth_pack *auth_pack = NULL;
    krb5_auth_pack_draft9 *auth_pack9 = NULL;
    pkinit_kdc_context plgctx = NULL;
    pkinit_kdc_req_context reqctx;
/* Solaris Kerberos: set but not used */
#if 0
    krb5_preauthtype pa_type;
#endif
    krb5_checksum cksum = {0, 0, 0, NULL};
    krb5_data *der_req = NULL;
    int valid_eku = 0, valid_san = 0;
    krb5_authdata **my_authz_data = NULL, *pkinit_authz_data = NULL;
    krb5_kdc_req *tmp_as_req = NULL;
    krb5_data k5data;

    pkiDebug("pkinit_verify_padata: entered!\n");
    /* Solaris Kerberos */
    if (data == NULL || data->length == 0 || data->contents == NULL)
    return 0;

    if (pa_plugin_context == NULL || e_data == NULL)
    return EINVAL;

    plgctx = pkinit_find_realm_context(context, pa_plugin_context,
                       request->server);
    if (plgctx == NULL)
    return 0;

#ifdef DEBUG_ASN1
    print_buffer_bin(data->contents, data->length, "/tmp/kdc_as_req");
#endif
    /* create a per-request context */
    retval = pkinit_init_kdc_req_context(context, (void **)&reqctx);
    if (retval)
    goto cleanup;
    reqctx->pa_type = data->pa_type;

    PADATA_TO_KRB5DATA(data, &k5data);

    switch ((int)data->pa_type) {
    case KRB5_PADATA_PK_AS_REQ:
        pkiDebug("processing KRB5_PADATA_PK_AS_REQ\n");
        retval = k5int_decode_krb5_pa_pk_as_req(&k5data, &reqp);
        if (retval) {
        pkiDebug("decode_krb5_pa_pk_as_req failed\n");
        goto cleanup;
        }
#ifdef DEBUG_ASN1
        print_buffer_bin(reqp->signedAuthPack.data,
                 reqp->signedAuthPack.length,
                 "/tmp/kdc_signed_data");
#endif
        retval = cms_signeddata_verify(context, plgctx->cryptoctx,
        reqctx->cryptoctx, plgctx->idctx, CMS_SIGN_CLIENT,
        plgctx->opts->require_crl_checking,
        reqp->signedAuthPack.data, reqp->signedAuthPack.length,
        &authp_data.data, &authp_data.length, &krb5_authz.data,
        &krb5_authz.length);
        break;
    case KRB5_PADATA_PK_AS_REP_OLD:
    case KRB5_PADATA_PK_AS_REQ_OLD:
        pkiDebug("processing KRB5_PADATA_PK_AS_REQ_OLD\n");
        retval = k5int_decode_krb5_pa_pk_as_req_draft9(&k5data, &reqp9);
        if (retval) {
        pkiDebug("decode_krb5_pa_pk_as_req_draft9 failed\n");
        goto cleanup;
        }
#ifdef DEBUG_ASN1
        print_buffer_bin(reqp9->signedAuthPack.data,
                 reqp9->signedAuthPack.length,
                 "/tmp/kdc_signed_data_draft9");
#endif

        retval = cms_signeddata_verify(context, plgctx->cryptoctx,
        reqctx->cryptoctx, plgctx->idctx, CMS_SIGN_DRAFT9,
        plgctx->opts->require_crl_checking,
        reqp9->signedAuthPack.data, reqp9->signedAuthPack.length,
        &authp_data.data, &authp_data.length, &krb5_authz.data,
        &krb5_authz.length);
        break;
    default:
        pkiDebug("unrecognized pa_type = %d\n", data->pa_type);
        retval = EINVAL;
        goto cleanup;
    }
    if (retval) {
    pkiDebug("pkcs7_signeddata_verify failed\n");
    goto cleanup;
    }

    retval = verify_client_san(context, plgctx, reqctx, request->client,
                   &valid_san);
    if (retval)
    goto cleanup;
    if (!valid_san) {
    pkiDebug("%s: did not find an acceptable SAN in user certificate\n",
         __FUNCTION__);
    retval = KRB5KDC_ERR_CLIENT_NAME_MISMATCH;
    goto cleanup;
    }
    retval = verify_client_eku(context, plgctx, reqctx, &valid_eku);
    if (retval)
    goto cleanup;

    if (!valid_eku) {
    pkiDebug("%s: did not find an acceptable EKU in user certificate\n",
         __FUNCTION__);
    retval = KRB5KDC_ERR_INCONSISTENT_KEY_PURPOSE;
    goto cleanup;
    }

#ifdef DEBUG_ASN1
    print_buffer_bin(authp_data.data, authp_data.length, "/tmp/kdc_auth_pack");
#endif

    OCTETDATA_TO_KRB5DATA(&authp_data, &k5data);
    switch ((int)data->pa_type) {
    case KRB5_PADATA_PK_AS_REQ:
        retval = k5int_decode_krb5_auth_pack(&k5data, &auth_pack);
        if (retval) {
        pkiDebug("failed to decode krb5_auth_pack\n");
        goto cleanup;
        }

        /* check dh parameters */
        if (auth_pack->clientPublicValue != NULL) {
        retval = server_check_dh(context, plgctx->cryptoctx,
            reqctx->cryptoctx, plgctx->idctx,
            &auth_pack->clientPublicValue->algorithm.parameters,
            plgctx->opts->dh_min_bits);

        if (retval) {
            pkiDebug("bad dh parameters\n");
            goto cleanup;
        }
        }
        /*
         * The KDC may have modified the request after decoding it.
         * We need to compute the checksum on the data that
         * came from the client.  Therefore, we use the original
         * packet contents.
         */
        retval = k5int_decode_krb5_as_req(req_pkt, &tmp_as_req);
        if (retval) {
        pkiDebug("decode_krb5_as_req returned %d\n", (int)retval);
        goto cleanup;
        }

        retval = k5int_encode_krb5_kdc_req_body(tmp_as_req, &der_req);
        if (retval) {
        pkiDebug("encode_krb5_kdc_req_body returned %d\n", (int) retval);
        goto cleanup;
        }
        retval = krb5_c_make_checksum(context, CKSUMTYPE_NIST_SHA, NULL,
                      0, der_req, &cksum);
        if (retval) {
        pkiDebug("unable to calculate AS REQ checksum\n");
        goto cleanup;
        }
        if (cksum.length != auth_pack->pkAuthenticator.paChecksum.length ||
        memcmp(cksum.contents,
               auth_pack->pkAuthenticator.paChecksum.contents,
               cksum.length)) {
        pkiDebug("failed to match the checksum\n");
#ifdef DEBUG_CKSUM
        pkiDebug("calculating checksum on buf size (%d)\n",
             req_pkt->length);
        print_buffer(req_pkt->data, req_pkt->length);
        pkiDebug("received checksum type=%d size=%d ",
            auth_pack->pkAuthenticator.paChecksum.checksum_type,
            auth_pack->pkAuthenticator.paChecksum.length);
        print_buffer(auth_pack->pkAuthenticator.paChecksum.contents,
                 auth_pack->pkAuthenticator.paChecksum.length);
        pkiDebug("expected checksum type=%d size=%d ",
             cksum.checksum_type, cksum.length);
        print_buffer(cksum.contents, cksum.length);
#endif

        retval = KRB5KDC_ERR_PA_CHECKSUM_MUST_BE_INCLUDED;
        goto cleanup;
        }

        /* check if kdcPkId present and match KDC's subjectIdentifier */
        if (reqp->kdcPkId.data != NULL) {
        int valid_kdcPkId = 0;
        retval = pkinit_check_kdc_pkid(context, plgctx->cryptoctx,
            reqctx->cryptoctx, plgctx->idctx,
            reqp->kdcPkId.data, reqp->kdcPkId.length, &valid_kdcPkId);
        if (retval)
            goto cleanup;
        if (!valid_kdcPkId)
            pkiDebug("kdcPkId in AS_REQ does not match KDC's cert"
                 "RFC says to ignore and proceed\n");

        }
        /* remember the decoded auth_pack for verify_padata routine */
        reqctx->rcv_auth_pack = auth_pack;
        auth_pack = NULL;
        break;
    case KRB5_PADATA_PK_AS_REP_OLD:
    case KRB5_PADATA_PK_AS_REQ_OLD:
        retval = k5int_decode_krb5_auth_pack_draft9(&k5data, &auth_pack9);
        if (retval) {
        pkiDebug("failed to decode krb5_auth_pack_draft9\n");
        goto cleanup;
        }
        if (auth_pack9->clientPublicValue != NULL) {
        retval = server_check_dh(context, plgctx->cryptoctx,
            reqctx->cryptoctx, plgctx->idctx,
            &auth_pack9->clientPublicValue->algorithm.parameters,
            plgctx->opts->dh_min_bits);

        if (retval) {
            pkiDebug("bad dh parameters\n");
            goto cleanup;
        }
        }
        /* remember the decoded auth_pack for verify_padata routine */
        reqctx->rcv_auth_pack9 = auth_pack9;
        auth_pack9 = NULL;
        break;
    }

    /* return authorization data to be included in the ticket */
    switch ((int)data->pa_type) {
    case KRB5_PADATA_PK_AS_REQ:
        my_authz_data = malloc(2 * sizeof(*my_authz_data));
        if (my_authz_data == NULL) {
        retval = ENOMEM;
        pkiDebug("Couldn't allocate krb5_authdata ptr array\n");
        goto cleanup;
        }
        my_authz_data[1] = NULL;
        my_authz_data[0] = malloc(sizeof(krb5_authdata));
        if (my_authz_data[0] == NULL) {
        retval = ENOMEM;
        pkiDebug("Couldn't allocate krb5_authdata\n");
        free(my_authz_data);
        goto cleanup;
        }
        /* AD-INITIAL-VERIFIED-CAS must be wrapped in AD-IF-RELEVANT */
        my_authz_data[0]->magic = KV5M_AUTHDATA;
        my_authz_data[0]->ad_type = KRB5_AUTHDATA_IF_RELEVANT;

        /* create an internal AD-INITIAL-VERIFIED-CAS data */
        pkinit_authz_data = malloc(sizeof(krb5_authdata));
        if (pkinit_authz_data == NULL) {
        retval = ENOMEM;
        pkiDebug("Couldn't allocate krb5_authdata\n");
        free(my_authz_data[0]);
        free(my_authz_data);
        goto cleanup;
        }
        pkinit_authz_data->ad_type = KRB5_AUTHDATA_INITIAL_VERIFIED_CAS;
        /* content of this ad-type contains the certification
           path with which the client certificate was validated
         */
        pkinit_authz_data->contents = krb5_authz.data;
        pkinit_authz_data->length = krb5_authz.length;
        retval = k5int_encode_krb5_authdata_elt(pkinit_authz_data,
                &encoded_pkinit_authz_data);
#ifdef DEBUG_ASN1
        print_buffer_bin((unsigned char *)encoded_pkinit_authz_data->data,
                 encoded_pkinit_authz_data->length,
                 "/tmp/kdc_pkinit_authz_data");
#endif
        free(pkinit_authz_data);
        if (retval) {
        pkiDebug("k5int_encode_krb5_authdata_elt failed\n");
        free(my_authz_data[0]);
        free(my_authz_data);
        goto cleanup;
        }

        my_authz_data[0]->contents =
                (krb5_octet *) encoded_pkinit_authz_data->data;
        my_authz_data[0]->length = encoded_pkinit_authz_data->length;
        *authz_data = my_authz_data;
        pkiDebug("Returning %d bytes of authorization data\n",
             krb5_authz.length);
        encoded_pkinit_authz_data->data = NULL; /* Don't free during cleanup*/
        free(encoded_pkinit_authz_data);
        break;
    default:
        *authz_data = NULL;
    }
    /* remember to set the PREAUTH flag in the reply */
    enc_tkt_reply->flags |= TKT_FLG_PRE_AUTH;
    *pa_request_context = reqctx;
    reqctx = NULL;

  cleanup:
    if (retval && data->pa_type == KRB5_PADATA_PK_AS_REQ) {
    pkiDebug("pkinit_verify_padata failed: creating e-data\n");
    if (pkinit_create_edata(context, plgctx->cryptoctx, reqctx->cryptoctx,
        plgctx->idctx, plgctx->opts, retval, e_data))
        pkiDebug("pkinit_create_edata failed\n");
    }

    switch ((int)data->pa_type) {
    case KRB5_PADATA_PK_AS_REQ:
        free_krb5_pa_pk_as_req(&reqp);
        if (cksum.contents != NULL)
        free(cksum.contents);
        if (der_req != NULL)
         krb5_free_data(context, der_req);
        break;
    case KRB5_PADATA_PK_AS_REP_OLD:
    case KRB5_PADATA_PK_AS_REQ_OLD:
        free_krb5_pa_pk_as_req_draft9(&reqp9);
    }
    if (tmp_as_req != NULL)
    k5int_krb5_free_kdc_req(context, tmp_as_req);
    if (authp_data.data != NULL)
    free(authp_data.data);
    if (krb5_authz.data != NULL)
    free(krb5_authz.data);
    if (reqctx != NULL)
    pkinit_fini_kdc_req_context(context, reqctx);
    if (auth_pack != NULL)
    free_krb5_auth_pack(&auth_pack);
    if (auth_pack9 != NULL)
    free_krb5_auth_pack_draft9(context, &auth_pack9);

    return retval;
}

/* ARGSUSED */
static krb5_error_code
pkinit_server_return_padata(krb5_context context,
                krb5_pa_data * padata,
                struct _krb5_db_entry_new * client,
                krb5_data *req_pkt,
                krb5_kdc_req * request,
                krb5_kdc_rep * reply,
                struct _krb5_key_data * client_key,
                krb5_keyblock * encrypting_key,
                krb5_pa_data ** send_pa,
                preauth_get_entry_data_proc server_get_entry_data,
                void *pa_plugin_context,
                void **pa_request_context)
{
    krb5_error_code retval = 0;
    krb5_data scratch = {0, 0, NULL};
    krb5_pa_pk_as_req *reqp = NULL;
    krb5_pa_pk_as_req_draft9 *reqp9 = NULL;
    int i = 0;

    unsigned char *subjectPublicKey = NULL;
    unsigned char *dh_pubkey = NULL, *server_key = NULL;
    unsigned int subjectPublicKey_len = 0;
    unsigned int server_key_len = 0, dh_pubkey_len = 0;

    krb5_kdc_dh_key_info dhkey_info;
    krb5_data *encoded_dhkey_info = NULL;
    krb5_pa_pk_as_rep *rep = NULL;
    krb5_pa_pk_as_rep_draft9 *rep9 = NULL;
    krb5_data *out_data = NULL;

    krb5_enctype enctype = -1;

    krb5_reply_key_pack *key_pack = NULL;
    krb5_reply_key_pack_draft9 *key_pack9 = NULL;
    krb5_data *encoded_key_pack = NULL;
    unsigned int num_types;
    krb5_cksumtype *cksum_types = NULL;

    pkinit_kdc_context plgctx;
    pkinit_kdc_req_context reqctx;

    int fixed_keypack = 0;

    *send_pa = NULL;
    /* Solaris Kerberos */
    if (padata == NULL || padata->length == 0 || padata->contents == NULL)
    return 0;

    if (pa_request_context == NULL || *pa_request_context == NULL) {
    pkiDebug("missing request context \n");
    return EINVAL;
    }

    plgctx = pkinit_find_realm_context(context, pa_plugin_context,
                       request->server);
    if (plgctx == NULL) {
    pkiDebug("Unable to locate correct realm context\n");
    return ENOENT;
    }

    pkiDebug("pkinit_return_padata: entered!\n");
    reqctx = (pkinit_kdc_req_context)*pa_request_context;

    if (encrypting_key->contents) {
    free(encrypting_key->contents);
    encrypting_key->length = 0;
    encrypting_key->contents = NULL;
    }

    for(i = 0; i < request->nktypes; i++) {
    enctype = request->ktype[i];
    if (!krb5_c_valid_enctype(enctype))
        continue;
    else {
        pkiDebug("KDC picked etype = %d\n", enctype);
        break;
    }
    }

    if (i == request->nktypes) {
    retval = KRB5KDC_ERR_ETYPE_NOSUPP;
    goto cleanup;
    }

    switch((int)reqctx->pa_type) {
    case KRB5_PADATA_PK_AS_REQ:
        init_krb5_pa_pk_as_rep(&rep);
        if (rep == NULL) {
        retval = ENOMEM;
        goto cleanup;
        }
        /* let's assume it's RSA. we'll reset it to DH if needed */
        rep->choice = choice_pa_pk_as_rep_encKeyPack;
        break;
    case KRB5_PADATA_PK_AS_REP_OLD:
    case KRB5_PADATA_PK_AS_REQ_OLD:
        init_krb5_pa_pk_as_rep_draft9(&rep9);
        if (rep9 == NULL) {
        retval = ENOMEM;
        goto cleanup;
        }
        rep9->choice = choice_pa_pk_as_rep_draft9_encKeyPack;
        break;
    default:
        retval = KRB5KDC_ERR_PREAUTH_FAILED;
        goto cleanup;
    }

    if (reqctx->rcv_auth_pack != NULL &&
        reqctx->rcv_auth_pack->clientPublicValue != NULL) {
    subjectPublicKey =
        reqctx->rcv_auth_pack->clientPublicValue->subjectPublicKey.data;
    subjectPublicKey_len =
        reqctx->rcv_auth_pack->clientPublicValue->subjectPublicKey.length;
    rep->choice = choice_pa_pk_as_rep_dhInfo;
    } else if (reqctx->rcv_auth_pack9 != NULL &&
        reqctx->rcv_auth_pack9->clientPublicValue != NULL) {
    subjectPublicKey =
        reqctx->rcv_auth_pack9->clientPublicValue->subjectPublicKey.data;
    subjectPublicKey_len =
        reqctx->rcv_auth_pack9->clientPublicValue->subjectPublicKey.length;
    rep9->choice = choice_pa_pk_as_rep_draft9_dhSignedData;
    }

    /* if this DH, then process finish computing DH key */
    if (((rep != NULL) && (rep->choice == choice_pa_pk_as_rep_dhInfo)) ||
    ((rep9 != NULL) && rep9->choice ==
        choice_pa_pk_as_rep_draft9_dhSignedData)) {
    pkiDebug("received DH key delivery AS REQ\n");
    retval = server_process_dh(context, plgctx->cryptoctx,
        reqctx->cryptoctx, plgctx->idctx, subjectPublicKey,
        subjectPublicKey_len, &dh_pubkey, &dh_pubkey_len,
        &server_key, &server_key_len);
    if (retval) {
        pkiDebug("failed to process/create dh paramters\n");
        goto cleanup;
    }
    }

    if ((rep9 != NULL &&
        rep9->choice == choice_pa_pk_as_rep_draft9_dhSignedData) ||
    (rep != NULL && rep->choice == choice_pa_pk_as_rep_dhInfo)) {
    retval = pkinit_octetstring2key(context, enctype, server_key,
                    server_key_len, encrypting_key);
    if (retval) {
        pkiDebug("pkinit_octetstring2key failed: %s\n",
             error_message(retval));
        goto cleanup;
    }

    dhkey_info.subjectPublicKey.length = dh_pubkey_len;
    dhkey_info.subjectPublicKey.data = dh_pubkey;
    dhkey_info.nonce = request->nonce;
    dhkey_info.dhKeyExpiration = 0;

    retval = k5int_encode_krb5_kdc_dh_key_info(&dhkey_info,
                           &encoded_dhkey_info);
    if (retval) {
        pkiDebug("encode_krb5_kdc_dh_key_info failed\n");
        goto cleanup;
    }
#ifdef DEBUG_ASN1
    print_buffer_bin((unsigned char *)encoded_dhkey_info->data,
             encoded_dhkey_info->length,
             "/tmp/kdc_dh_key_info");
#endif

    switch ((int)padata->pa_type) {
        case KRB5_PADATA_PK_AS_REQ:
        retval = cms_signeddata_create(context, plgctx->cryptoctx,
            reqctx->cryptoctx, plgctx->idctx, CMS_SIGN_SERVER, 1,
            (unsigned char *)encoded_dhkey_info->data,
            encoded_dhkey_info->length,
            &rep->u.dh_Info.dhSignedData.data,
            &rep->u.dh_Info.dhSignedData.length);
        if (retval) {
            pkiDebug("failed to create pkcs7 signed data\n");
            goto cleanup;
        }
        break;
        case KRB5_PADATA_PK_AS_REP_OLD:
        case KRB5_PADATA_PK_AS_REQ_OLD:
        retval = cms_signeddata_create(context, plgctx->cryptoctx,
            reqctx->cryptoctx, plgctx->idctx, CMS_SIGN_DRAFT9, 1,
            (unsigned char *)encoded_dhkey_info->data,
            encoded_dhkey_info->length,
            &rep9->u.dhSignedData.data,
            &rep9->u.dhSignedData.length);
        if (retval) {
            pkiDebug("failed to create pkcs7 signed data\n");
            goto cleanup;
        }
        break;
    }
    } else {
    pkiDebug("received RSA key delivery AS REQ\n");

    retval = krb5_c_make_random_key(context, enctype, encrypting_key);
    if (retval) {
        pkiDebug("unable to make a session key\n");
        goto cleanup;
    }

    /* check if PA_TYPE of 132 is present which means the client is
     * requesting that a checksum is send back instead of the nonce
     */
    for (i = 0; request->padata[i] != NULL; i++) {
        pkiDebug("%s: Checking pa_type 0x%08x\n",
             __FUNCTION__, request->padata[i]->pa_type);
        if (request->padata[i]->pa_type == 132)
        fixed_keypack = 1;
    }
    pkiDebug("%s: return checksum instead of nonce = %d\n",
         __FUNCTION__, fixed_keypack);

    /* if this is an RFC reply or draft9 client requested a checksum
     * in the reply instead of the nonce, create an RFC-style keypack
     */
    if ((int)padata->pa_type == KRB5_PADATA_PK_AS_REQ || fixed_keypack) {
        init_krb5_reply_key_pack(&key_pack);
        if (key_pack == NULL) {
        retval = ENOMEM;
        goto cleanup;
        }
        /* retrieve checksums for a given enctype of the reply key */
        retval = krb5_c_keyed_checksum_types(context,
        encrypting_key->enctype, &num_types, &cksum_types);
        if (retval)
        goto cleanup;

        /* pick the first of acceptable enctypes for the checksum */
        retval = krb5_c_make_checksum(context, cksum_types[0],
            encrypting_key, KRB5_KEYUSAGE_TGS_REQ_AUTH_CKSUM,
            req_pkt, &key_pack->asChecksum);
        if (retval) {
        pkiDebug("unable to calculate AS REQ checksum\n");
        goto cleanup;
        }
#ifdef DEBUG_CKSUM
        pkiDebug("calculating checksum on buf size = %d\n", req_pkt->length);
        print_buffer(req_pkt->data, req_pkt->length);
        pkiDebug("checksum size = %d\n", key_pack->asChecksum.length);
        print_buffer(key_pack->asChecksum.contents,
             key_pack->asChecksum.length);
        pkiDebug("encrypting key (%d)\n", encrypting_key->length);
        print_buffer(encrypting_key->contents, encrypting_key->length);
#endif

        krb5_copy_keyblock_contents(context, encrypting_key,
                    &key_pack->replyKey);

        retval = k5int_encode_krb5_reply_key_pack(key_pack,
                              &encoded_key_pack);
        if (retval) {
        pkiDebug("failed to encode reply_key_pack\n");
        goto cleanup;
        }
    }

    switch ((int)padata->pa_type) {
        case KRB5_PADATA_PK_AS_REQ:
        rep->choice = choice_pa_pk_as_rep_encKeyPack;
        retval = cms_envelopeddata_create(context, plgctx->cryptoctx,
            reqctx->cryptoctx, plgctx->idctx, padata->pa_type, 1,
            (unsigned char *)encoded_key_pack->data,
            encoded_key_pack->length,
            &rep->u.encKeyPack.data, &rep->u.encKeyPack.length);
        break;
        case KRB5_PADATA_PK_AS_REP_OLD:
        case KRB5_PADATA_PK_AS_REQ_OLD:
        /* if the request is from the broken draft9 client that
         * expects back a nonce, create it now
         */
        if (!fixed_keypack) {
            init_krb5_reply_key_pack_draft9(&key_pack9);
            if (key_pack9 == NULL) {
            retval = ENOMEM;
            goto cleanup;
            }
            key_pack9->nonce = reqctx->rcv_auth_pack9->pkAuthenticator.nonce;
            krb5_copy_keyblock_contents(context, encrypting_key,
                        &key_pack9->replyKey);

            retval = k5int_encode_krb5_reply_key_pack_draft9(key_pack9,
                               &encoded_key_pack);
            if (retval) {
            pkiDebug("failed to encode reply_key_pack\n");
            goto cleanup;
            }
        }

        rep9->choice = choice_pa_pk_as_rep_draft9_encKeyPack;
        retval = cms_envelopeddata_create(context, plgctx->cryptoctx,
            reqctx->cryptoctx, plgctx->idctx, padata->pa_type, 1,
            (unsigned char *)encoded_key_pack->data,
            encoded_key_pack->length,
            &rep9->u.encKeyPack.data, &rep9->u.encKeyPack.length);
        break;
    }
    if (retval) {
        pkiDebug("failed to create pkcs7 enveloped data: %s\n",
             error_message(retval));
        goto cleanup;
    }
#ifdef DEBUG_ASN1
    print_buffer_bin((unsigned char *)encoded_key_pack->data,
             encoded_key_pack->length,
             "/tmp/kdc_key_pack");
    switch ((int)padata->pa_type) {
        case KRB5_PADATA_PK_AS_REQ:
        print_buffer_bin(rep->u.encKeyPack.data,
                 rep->u.encKeyPack.length,
                 "/tmp/kdc_enc_key_pack");
        break;
        case KRB5_PADATA_PK_AS_REP_OLD:
        case KRB5_PADATA_PK_AS_REQ_OLD:
        print_buffer_bin(rep9->u.encKeyPack.data,
                 rep9->u.encKeyPack.length,
                 "/tmp/kdc_enc_key_pack");
        break;
    }
#endif
    }

    switch ((int)padata->pa_type) {
    case KRB5_PADATA_PK_AS_REQ:
        retval = k5int_encode_krb5_pa_pk_as_rep(rep, &out_data);
        break;
    case KRB5_PADATA_PK_AS_REP_OLD:
    case KRB5_PADATA_PK_AS_REQ_OLD:
        retval = k5int_encode_krb5_pa_pk_as_rep_draft9(rep9, &out_data);
        break;
    }
    if (retval) {
    pkiDebug("failed to encode AS_REP\n");
    goto cleanup;
    }
#ifdef DEBUG_ASN1
    if (out_data != NULL)
    print_buffer_bin((unsigned char *)out_data->data, out_data->length,
             "/tmp/kdc_as_rep");
#endif

    *send_pa = (krb5_pa_data *) malloc(sizeof(krb5_pa_data));
    if (*send_pa == NULL) {
    retval = ENOMEM;
    free(out_data->data);
    free(out_data);
    out_data = NULL;
    goto cleanup;
    }
    (*send_pa)->magic = KV5M_PA_DATA;
    switch ((int)padata->pa_type) {
    case KRB5_PADATA_PK_AS_REQ:
        (*send_pa)->pa_type = KRB5_PADATA_PK_AS_REP;
        break;
    case KRB5_PADATA_PK_AS_REQ_OLD:
    case KRB5_PADATA_PK_AS_REP_OLD:
        (*send_pa)->pa_type = KRB5_PADATA_PK_AS_REP_OLD;
        break;
    }
    (*send_pa)->length = out_data->length;
    (*send_pa)->contents = (krb5_octet *) out_data->data;


  cleanup:
    pkinit_fini_kdc_req_context(context, reqctx);
    if (scratch.data != NULL)
    free(scratch.data);
    if (out_data != NULL)
    free(out_data);
    if (encoded_dhkey_info != NULL)
    krb5_free_data(context, encoded_dhkey_info);
    if (encoded_key_pack != NULL)
    krb5_free_data(context, encoded_key_pack);
    if (dh_pubkey != NULL)
    free(dh_pubkey);
    if (server_key != NULL)
    free(server_key);
    if (cksum_types != NULL)
    free(cksum_types);

    switch ((int)padata->pa_type) {
    case KRB5_PADATA_PK_AS_REQ:
        free_krb5_pa_pk_as_req(&reqp);
        free_krb5_pa_pk_as_rep(&rep);
        free_krb5_reply_key_pack(&key_pack);
        break;
    case KRB5_PADATA_PK_AS_REP_OLD:
    case KRB5_PADATA_PK_AS_REQ_OLD:
        free_krb5_pa_pk_as_req_draft9(&reqp9);
        free_krb5_pa_pk_as_rep_draft9(&rep9);
        if (!fixed_keypack)
        free_krb5_reply_key_pack_draft9(&key_pack9);
        else
        free_krb5_reply_key_pack(&key_pack);
        break;
    }

    if (retval)
    pkiDebug("pkinit_verify_padata failure");

    return retval;
}

/* ARGSUSED */
static int
pkinit_server_get_flags(krb5_context kcontext, krb5_preauthtype patype)
{
    return PA_SUFFICIENT | PA_REPLACES_KEY;
}

static krb5_preauthtype supported_server_pa_types[] = {
    KRB5_PADATA_PK_AS_REQ,
    KRB5_PADATA_PK_AS_REQ_OLD,
    KRB5_PADATA_PK_AS_REP_OLD,
    0
};

/* ARGSUSED */
static void
pkinit_fini_kdc_profile(krb5_context context, pkinit_kdc_context plgctx)
{
    /*
     * There is nothing currently allocated by pkinit_init_kdc_profile()
     * which needs to be freed here.
     */
}

static krb5_error_code
pkinit_init_kdc_profile(krb5_context context, pkinit_kdc_context plgctx)
{
    krb5_error_code retval;
    char *eku_string = NULL;

    pkiDebug("%s: entered for realm %s\n", __FUNCTION__, plgctx->realmname);
    retval = pkinit_kdcdefault_string(context, plgctx->realmname,
                      "pkinit_identity",
                      &plgctx->idopts->identity);
    if (retval != 0 || NULL == plgctx->idopts->identity) {
    retval = EINVAL;
    krb5_set_error_message(context, retval,
                   "No pkinit_identity supplied for realm %s",
                   plgctx->realmname);
    goto errout;
    }

    retval = pkinit_kdcdefault_strings(context, plgctx->realmname,
                       "pkinit_anchors",
                       &plgctx->idopts->anchors);
    if (retval != 0 || NULL == plgctx->idopts->anchors) {
    retval = EINVAL;
    krb5_set_error_message(context, retval,
                   "No pkinit_anchors supplied for realm %s",
                   plgctx->realmname);
    goto errout;
    }

    /* Solaris Kerberos */
    (void) pkinit_kdcdefault_strings(context, plgctx->realmname,
                  "pkinit_pool",
                  &plgctx->idopts->intermediates);

    (void) pkinit_kdcdefault_strings(context, plgctx->realmname,
                  "pkinit_revoke",
                  &plgctx->idopts->crls);

    (void) pkinit_kdcdefault_string(context, plgctx->realmname,
                 "pkinit_kdc_ocsp",
                 &plgctx->idopts->ocsp);

    (void) pkinit_kdcdefault_string(context, plgctx->realmname,
                 "pkinit_mappings_file",
                 &plgctx->idopts->dn_mapping_file);

    (void) pkinit_kdcdefault_integer(context, plgctx->realmname,
                  "pkinit_dh_min_bits",
                  PKINIT_DEFAULT_DH_MIN_BITS,
                  &plgctx->opts->dh_min_bits);
    if (plgctx->opts->dh_min_bits < 1024) {
    pkiDebug("%s: invalid value (%d) for pkinit_dh_min_bits, "
         "using default value (%d) instead\n", __FUNCTION__,
         plgctx->opts->dh_min_bits, PKINIT_DEFAULT_DH_MIN_BITS);
    plgctx->opts->dh_min_bits = PKINIT_DEFAULT_DH_MIN_BITS;
    }

    (void) pkinit_kdcdefault_boolean(context, plgctx->realmname,
                  "pkinit_allow_upn",
                  0, &plgctx->opts->allow_upn);

    (void) pkinit_kdcdefault_boolean(context, plgctx->realmname,
                  "pkinit_require_crl_checking",
                  0, &plgctx->opts->require_crl_checking);

    (void) pkinit_kdcdefault_string(context, plgctx->realmname,
                 "pkinit_eku_checking",
                 &eku_string);
    if (eku_string != NULL) {
    if (strcasecmp(eku_string, "kpClientAuth") == 0) {
        plgctx->opts->require_eku = 1;
        plgctx->opts->accept_secondary_eku = 0;
    } else if (strcasecmp(eku_string, "scLogin") == 0) {
        plgctx->opts->require_eku = 1;
        plgctx->opts->accept_secondary_eku = 1;
    } else if (strcasecmp(eku_string, "none") == 0) {
        plgctx->opts->require_eku = 0;
        plgctx->opts->accept_secondary_eku = 0;
    } else {
        pkiDebug("%s: Invalid value for pkinit_eku_checking: '%s'\n",
             __FUNCTION__, eku_string);
    }
    free(eku_string);
    }


    return 0;
errout:
    pkinit_fini_kdc_profile(context, plgctx);
    return retval;
}

/* ARGSUSED */
static pkinit_kdc_context
pkinit_find_realm_context(krb5_context context, void *pa_plugin_context,
              krb5_principal princ)
{
    int i;
    pkinit_kdc_context *realm_contexts = pa_plugin_context;

    if (pa_plugin_context == NULL)
    return NULL;

    for (i = 0; realm_contexts[i] != NULL; i++) {
    pkinit_kdc_context p = realm_contexts[i];

    if ((p->realmname_len == princ->realm.length) &&
        (strncmp(p->realmname, princ->realm.data, p->realmname_len) == 0)) {
        pkiDebug("%s: returning context at %p for realm '%s'\n",
             __FUNCTION__, p, p->realmname);
        return p;
    }
    }
    pkiDebug("%s: unable to find realm context for realm '%.*s'\n",
         __FUNCTION__, princ->realm.length, princ->realm.data);
    return NULL;
}

static int
pkinit_server_plugin_init_realm(krb5_context context, const char *realmname,
                pkinit_kdc_context *pplgctx)
{
    krb5_error_code retval = ENOMEM;
    pkinit_kdc_context plgctx = NULL;

    *pplgctx = NULL;

    plgctx = (pkinit_kdc_context) calloc(1, sizeof(*plgctx));
    if (plgctx == NULL)
    goto errout;

    pkiDebug("%s: initializing context at %p for realm '%s'\n",
         __FUNCTION__, plgctx, realmname);
    (void) memset(plgctx, 0, sizeof(*plgctx));
    plgctx->magic = PKINIT_CTX_MAGIC;

    plgctx->realmname = strdup(realmname);
    if (plgctx->realmname == NULL)
    goto errout;
    plgctx->realmname_len = strlen(plgctx->realmname);

    retval = pkinit_init_plg_crypto(&plgctx->cryptoctx);
    if (retval)
    goto errout;

    retval = pkinit_init_plg_opts(&plgctx->opts);
    if (retval)
    goto errout;

    retval = pkinit_init_identity_crypto(&plgctx->idctx);
    if (retval)
    goto errout;

    retval = pkinit_init_identity_opts(&plgctx->idopts);
    if (retval)
    goto errout;

    retval = pkinit_init_kdc_profile(context, plgctx);
    if (retval)
    goto errout;

    /*
     * Solaris Kerberos:
     * Some methods of storing key information (PKCS11, PKCS12,...) may
     * require interactive prompting.
     */
    retval = pkinit_identity_set_prompter(plgctx->idctx, krb5_prompter_posix,
                    NULL);
    if (retval)
    goto errout;

    retval = pkinit_identity_initialize(context, plgctx->cryptoctx, NULL,
                    plgctx->idopts, plgctx->idctx, 0, NULL);
    if (retval)
    goto errout;

    pkiDebug("%s: returning context at %p for realm '%s'\n",
         __FUNCTION__, plgctx, realmname);
    *pplgctx = plgctx;
    retval = 0;

errout:
    if (retval)
    pkinit_server_plugin_fini_realm(context, plgctx);

    return retval;
}

static int
pkinit_server_plugin_init(krb5_context context, void **blob,
              const char **realmnames)
{
    krb5_error_code retval = ENOMEM;
    pkinit_kdc_context plgctx, *realm_contexts = NULL;
    int i, j;
    size_t numrealms;

    retval = pkinit_accessor_init();
    if (retval)
    return retval;

    /* Determine how many realms we may need to support */
    for (i = 0; realmnames[i] != NULL; i++) {};
    numrealms = i;

    realm_contexts = (pkinit_kdc_context *)
            calloc(numrealms+1, sizeof(pkinit_kdc_context));
    if (realm_contexts == NULL)
    return ENOMEM;

    for (i = 0, j = 0; i < numrealms; i++) {
    pkiDebug("%s: processing realm '%s'\n", __FUNCTION__, realmnames[i]);
    retval = pkinit_server_plugin_init_realm(context, realmnames[i], &plgctx);
    if (retval == 0 && plgctx != NULL)
        realm_contexts[j++] = plgctx;
    }

    if (j == 0) {
    /*
     * Solaris Kerberos
     * Improve error messages for the common case of a single realm
     */
    if (numrealms != 1) {
        retval = EINVAL;
        krb5_set_error_message(context, retval, "No realms configured "
                   "correctly for pkinit support");
    }

    goto errout;
    }

    *blob = realm_contexts;
    retval = 0;
    pkiDebug("%s: returning context at %p\n", __FUNCTION__, realm_contexts);

errout:
    if (retval)
    pkinit_server_plugin_fini(context, realm_contexts);

    return retval;
}

static void
pkinit_server_plugin_fini_realm(krb5_context context, pkinit_kdc_context plgctx)
{
    if (plgctx == NULL)
    return;

    pkinit_fini_kdc_profile(context, plgctx);
    pkinit_fini_identity_opts(plgctx->idopts);
    pkinit_fini_identity_crypto(plgctx->idctx);
    pkinit_fini_plg_crypto(plgctx->cryptoctx);
    pkinit_fini_plg_opts(plgctx->opts);
    free(plgctx->realmname);
    free(plgctx);
}

static void
pkinit_server_plugin_fini(krb5_context context, void *blob)
{
    pkinit_kdc_context *realm_contexts = blob;
    int i;

    if (realm_contexts == NULL)
    return;

    for (i = 0; realm_contexts[i] != NULL; i++) {
    pkinit_server_plugin_fini_realm(context, realm_contexts[i]);
    }
    pkiDebug("%s: freeing   context at %p\n", __FUNCTION__, realm_contexts);
    free(realm_contexts);
}

static krb5_error_code
pkinit_init_kdc_req_context(krb5_context context, void **ctx)
{
    krb5_error_code retval = ENOMEM;
    pkinit_kdc_req_context reqctx = NULL;

    reqctx = (pkinit_kdc_req_context)malloc(sizeof(*reqctx));
    if (reqctx == NULL)
    return retval;
    (void) memset(reqctx, 0, sizeof(*reqctx));
    reqctx->magic = PKINIT_CTX_MAGIC;

    retval = pkinit_init_req_crypto(&reqctx->cryptoctx);
    if (retval)
    goto cleanup;
    reqctx->rcv_auth_pack = NULL;
    reqctx->rcv_auth_pack9 = NULL;

    pkiDebug("%s: returning reqctx at %p\n", __FUNCTION__, reqctx);
    *ctx = reqctx;
    retval = 0;
cleanup:
    if (retval)
    pkinit_fini_kdc_req_context(context, reqctx);

    return retval;
}

static void
pkinit_fini_kdc_req_context(krb5_context context, void *ctx)
{
    pkinit_kdc_req_context reqctx = (pkinit_kdc_req_context)ctx;

    if (reqctx == NULL || reqctx->magic != PKINIT_CTX_MAGIC) {
    pkiDebug("pkinit_fini_kdc_req_context: got bad reqctx (%p)!\n", reqctx);
    return;
    }
    pkiDebug("%s: freeing   reqctx at %p\n", __FUNCTION__, reqctx);

    pkinit_fini_req_crypto(reqctx->cryptoctx);
    if (reqctx->rcv_auth_pack != NULL)
    free_krb5_auth_pack(&reqctx->rcv_auth_pack);
    if (reqctx->rcv_auth_pack9 != NULL)
    free_krb5_auth_pack_draft9(context, &reqctx->rcv_auth_pack9);

    free(reqctx);
}

struct krb5plugin_preauth_server_ftable_v1 preauthentication_server_1 = {
    "pkinit",           /* name */
    supported_server_pa_types,  /* pa_type_list */
    pkinit_server_plugin_init,  /* (*init_proc) */
    pkinit_server_plugin_fini,  /* (*fini_proc) */
    pkinit_server_get_flags,    /* (*flags_proc) */
    pkinit_server_get_edata,    /* (*edata_proc) */
    pkinit_server_verify_padata,/* (*verify_proc) */
    pkinit_server_return_padata,/* (*return_proc) */
    NULL,           /* (*freepa_reqcontext_proc) */
};