root/crypto/heimdal/kdc/pkinit.c
/*
 * Copyright (c) 2003 - 2008 Kungliga Tekniska Högskolan
 * (Royal Institute of Technology, Stockholm, Sweden).
 * All rights reserved.
 *
 * Portions Copyright (c) 2009 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * 3. Neither the name of the Institute nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include "kdc_locl.h"

#ifdef PKINIT

#include <heim_asn1.h>
#include <rfc2459_asn1.h>
#include <cms_asn1.h>
#include <pkinit_asn1.h>

#include <hx509.h>
#include "crypto-headers.h"

struct pk_client_params {
    enum krb5_pk_type type;
    enum { USE_RSA, USE_DH, USE_ECDH } keyex;
    union {
        struct {
            BIGNUM *public_key;
            DH *key;
        } dh;
#ifdef HAVE_OPENSSL
        struct {
            EC_KEY *public_key;
            EC_KEY *key;
        } ecdh;
#endif
    } u;
    hx509_cert cert;
    unsigned nonce;
    EncryptionKey reply_key;
    char *dh_group_name;
    hx509_peer_info peer;
    hx509_certs client_anchors;
    hx509_verify_ctx verify_ctx;
};

struct pk_principal_mapping {
    unsigned int len;
    struct pk_allowed_princ {
        krb5_principal principal;
        char *subject;
    } *val;
};

static struct krb5_pk_identity *kdc_identity;
static struct pk_principal_mapping principal_mappings;
static struct krb5_dh_moduli **moduli;

static struct {
    krb5_data data;
    time_t expire;
    time_t next_update;
} ocsp;

/*
 *
 */

static krb5_error_code
pk_check_pkauthenticator_win2k(krb5_context context,
                               PKAuthenticator_Win2k *a,
                               const KDC_REQ *req)
{
    krb5_timestamp now;

    krb5_timeofday (context, &now);

    /* XXX cusec */
    if (a->ctime == 0 || abs(a->ctime - now) > context->max_skew) {
        krb5_clear_error_message(context);
        return KRB5KRB_AP_ERR_SKEW;
    }
    return 0;
}

static krb5_error_code
pk_check_pkauthenticator(krb5_context context,
                         PKAuthenticator *a,
                         const KDC_REQ *req)
{
    u_char *buf = NULL;
    size_t buf_size;
    krb5_error_code ret;
    size_t len = 0;
    krb5_timestamp now;
    Checksum checksum;

    krb5_timeofday (context, &now);

    /* XXX cusec */
    if (a->ctime == 0 || abs(a->ctime - now) > context->max_skew) {
        krb5_clear_error_message(context);
        return KRB5KRB_AP_ERR_SKEW;
    }

    ASN1_MALLOC_ENCODE(KDC_REQ_BODY, buf, buf_size, &req->req_body, &len, ret);
    if (ret) {
        krb5_clear_error_message(context);
        return ret;
    }
    if (buf_size != len)
        krb5_abortx(context, "Internal error in ASN.1 encoder");

    ret = krb5_create_checksum(context,
                               NULL,
                               0,
                               CKSUMTYPE_SHA1,
                               buf,
                               len,
                               &checksum);
    free(buf);
    if (ret) {
        krb5_clear_error_message(context);
        return ret;
    }

    if (a->paChecksum == NULL) {
        krb5_clear_error_message(context);
        ret = KRB5_KDC_ERR_PA_CHECKSUM_MUST_BE_INCLUDED;
        goto out;
    }

    if (der_heim_octet_string_cmp(a->paChecksum, &checksum.checksum) != 0) {
        krb5_clear_error_message(context);
        ret = KRB5KRB_ERR_GENERIC;
    }

out:
    free_Checksum(&checksum);

    return ret;
}

void
_kdc_pk_free_client_param(krb5_context context, pk_client_params *cp)
{
    if (cp == NULL)
        return;
    if (cp->cert)
        hx509_cert_free(cp->cert);
    if (cp->verify_ctx)
        hx509_verify_destroy_ctx(cp->verify_ctx);
    if (cp->keyex == USE_DH) {
        if (cp->u.dh.key)
            DH_free(cp->u.dh.key);
        if (cp->u.dh.public_key)
            BN_free(cp->u.dh.public_key);
    }
#ifdef HAVE_OPENSSL
    if (cp->keyex == USE_ECDH) {
        if (cp->u.ecdh.key)
            EC_KEY_free(cp->u.ecdh.key);
        if (cp->u.ecdh.public_key)
            EC_KEY_free(cp->u.ecdh.public_key);
    }
#endif
    krb5_free_keyblock_contents(context, &cp->reply_key);
    if (cp->dh_group_name)
        free(cp->dh_group_name);
    if (cp->peer)
        hx509_peer_info_free(cp->peer);
    if (cp->client_anchors)
        hx509_certs_free(&cp->client_anchors);
    memset(cp, 0, sizeof(*cp));
    free(cp);
}

static krb5_error_code
generate_dh_keyblock(krb5_context context,
                     pk_client_params *client_params,
                     krb5_enctype enctype)
{
    unsigned char *dh_gen_key = NULL;
    krb5_keyblock key;
    krb5_error_code ret;
    size_t dh_gen_keylen, size;

    memset(&key, 0, sizeof(key));

    if (client_params->keyex == USE_DH) {

        if (client_params->u.dh.public_key == NULL) {
            ret = KRB5KRB_ERR_GENERIC;
            krb5_set_error_message(context, ret, "public_key");
            goto out;
        }

        if (!DH_generate_key(client_params->u.dh.key)) {
            ret = KRB5KRB_ERR_GENERIC;
            krb5_set_error_message(context, ret,
                                   "Can't generate Diffie-Hellman keys");
            goto out;
        }

        size = DH_size(client_params->u.dh.key);

        dh_gen_key = malloc(size);
        if (dh_gen_key == NULL) {
            ret = ENOMEM;
            krb5_set_error_message(context, ret, "malloc: out of memory");
            goto out;
        }

        dh_gen_keylen = DH_compute_key(dh_gen_key,client_params->u.dh.public_key, client_params->u.dh.key);
        if (dh_gen_keylen == (size_t)-1) {
            ret = KRB5KRB_ERR_GENERIC;
            krb5_set_error_message(context, ret,
                                   "Can't compute Diffie-Hellman key");
            goto out;
        }
        if (dh_gen_keylen < size) {
            size -= dh_gen_keylen;
            memmove(dh_gen_key + size, dh_gen_key, dh_gen_keylen);
            memset(dh_gen_key, 0, size);
        }

#ifdef HAVE_OPENSSL
    } else if (client_params->keyex == USE_ECDH) {

        if (client_params->u.ecdh.public_key == NULL) {
            ret = KRB5KRB_ERR_GENERIC;
            krb5_set_error_message(context, ret, "public_key");
            goto out;
        }

        client_params->u.ecdh.key = EC_KEY_new();
        if (client_params->u.ecdh.key == NULL) {
            ret = ENOMEM;
            goto out;
        }
        EC_KEY_set_group(client_params->u.ecdh.key,
                         EC_KEY_get0_group(client_params->u.ecdh.public_key));

        if (EC_KEY_generate_key(client_params->u.ecdh.key) != 1) {
            ret = ENOMEM;
            goto out;
        }

        size = (EC_GROUP_get_degree(EC_KEY_get0_group(client_params->u.ecdh.key)) + 7) / 8;
        dh_gen_key = malloc(size);
        if (dh_gen_key == NULL) {
            ret = ENOMEM;
            krb5_set_error_message(context, ret,
                                   N_("malloc: out of memory", ""));
            goto out;
        }

        dh_gen_keylen = ECDH_compute_key(dh_gen_key, size,
                                         EC_KEY_get0_public_key(client_params->u.ecdh.public_key),
                                         client_params->u.ecdh.key, NULL);

#endif /* HAVE_OPENSSL */
    } else {
        ret = KRB5KRB_ERR_GENERIC;
        krb5_set_error_message(context, ret,
                               "Diffie-Hellman not selected keys");
        goto out;
    }

    ret = _krb5_pk_octetstring2key(context,
                                   enctype,
                                   dh_gen_key, dh_gen_keylen,
                                   NULL, NULL,
                                   &client_params->reply_key);

 out:
    if (dh_gen_key)
        free(dh_gen_key);
    if (key.keyvalue.data)
        krb5_free_keyblock_contents(context, &key);

    return ret;
}

static BIGNUM *
integer_to_BN(krb5_context context, const char *field, heim_integer *f)
{
    BIGNUM *bn;

    bn = BN_bin2bn((const unsigned char *)f->data, f->length, NULL);
    if (bn == NULL) {
        krb5_set_error_message(context, KRB5_BADMSGTYPE,
                               "PKINIT: parsing BN failed %s", field);
        return NULL;
    }
    BN_set_negative(bn, f->negative);
    return bn;
}

static krb5_error_code
get_dh_param(krb5_context context,
             krb5_kdc_configuration *config,
             SubjectPublicKeyInfo *dh_key_info,
             pk_client_params *client_params)
{
    DomainParameters dhparam;
    DH *dh = NULL;
    BIGNUM *p, *q, *g;
    krb5_error_code ret;

    memset(&dhparam, 0, sizeof(dhparam));

    if ((dh_key_info->subjectPublicKey.length % 8) != 0) {
        ret = KRB5_BADMSGTYPE;
        krb5_set_error_message(context, ret,
                               "PKINIT: subjectPublicKey not aligned "
                               "to 8 bit boundary");
        goto out;
    }

    if (dh_key_info->algorithm.parameters == NULL) {
        krb5_set_error_message(context, KRB5_BADMSGTYPE,
                               "PKINIT missing algorithm parameter "
                              "in clientPublicValue");
        return KRB5_BADMSGTYPE;
    }

    ret = decode_DomainParameters(dh_key_info->algorithm.parameters->data,
                                  dh_key_info->algorithm.parameters->length,
                                  &dhparam,
                                  NULL);
    if (ret) {
        krb5_set_error_message(context, ret, "Can't decode algorithm "
                               "parameters in clientPublicValue");
        goto out;
    }

    ret = _krb5_dh_group_ok(context, config->pkinit_dh_min_bits,
                            &dhparam.p, &dhparam.g, &dhparam.q, moduli,
                            &client_params->dh_group_name);
    if (ret) {
        /* XXX send back proposal of better group */
        goto out;
    }

    dh = DH_new();
    if (dh == NULL) {
        ret = ENOMEM;
        krb5_set_error_message(context, ret, "Cannot create DH structure");
        goto out;
    }
    ret = KRB5_BADMSGTYPE;
    p = integer_to_BN(context, "DH prime", &dhparam.p);
    g = integer_to_BN(context, "DH base", &dhparam.g);
    q = integer_to_BN(context, "DH p-1 factor", &dhparam.q);
    if (p == NULL || g == NULL || q == NULL) {
        BN_free(p);
        BN_free(g);
        BN_free(q);
        goto out;
    }
    if (DH_set0_pqg(dh, p, g, q) != 1) {
        BN_free(p);
        BN_free(g);
        BN_free(q);
        goto out;
    }

    {
        heim_integer glue;
        size_t size;

        ret = decode_DHPublicKey(dh_key_info->subjectPublicKey.data,
                                 dh_key_info->subjectPublicKey.length / 8,
                                 &glue,
                                 &size);
        if (ret) {
            krb5_clear_error_message(context);
            return ret;
        }

        client_params->u.dh.public_key = integer_to_BN(context,
                                                       "subjectPublicKey",
                                                       &glue);
        der_free_heim_integer(&glue);
        if (client_params->u.dh.public_key == NULL) {
            ret = KRB5_BADMSGTYPE;
            goto out;
        }
    }

    client_params->u.dh.key = dh;
    dh = NULL;
    ret = 0;

 out:
    if (dh)
        DH_free(dh);
    free_DomainParameters(&dhparam);
    return ret;
}

#ifdef HAVE_OPENSSL

static krb5_error_code
get_ecdh_param(krb5_context context,
               krb5_kdc_configuration *config,
               SubjectPublicKeyInfo *dh_key_info,
               pk_client_params *client_params)
{
    ECParameters ecp;
    EC_KEY *public = NULL;
    krb5_error_code ret;
    const unsigned char *p;
    size_t len;
    int nid;

    if (dh_key_info->algorithm.parameters == NULL) {
        krb5_set_error_message(context, KRB5_BADMSGTYPE,
                               "PKINIT missing algorithm parameter "
                               "in clientPublicValue");
        return KRB5_BADMSGTYPE;
    }

    memset(&ecp, 0, sizeof(ecp));

    ret = decode_ECParameters(dh_key_info->algorithm.parameters->data,
                              dh_key_info->algorithm.parameters->length, &ecp, &len);
    if (ret)
        goto out;

    if (ecp.element != choice_ECParameters_namedCurve) {
        ret = KRB5_BADMSGTYPE;
        goto out;
    }

    if (der_heim_oid_cmp(&ecp.u.namedCurve, &asn1_oid_id_ec_group_secp256r1) == 0)
        nid = NID_X9_62_prime256v1;
    else {
        ret = KRB5_BADMSGTYPE;
        goto out;
    }

    /* XXX verify group is ok */

    public = EC_KEY_new_by_curve_name(nid);

    p = dh_key_info->subjectPublicKey.data;
    len = dh_key_info->subjectPublicKey.length / 8;
    if (o2i_ECPublicKey(&public, &p, len) == NULL) {
        ret = KRB5_BADMSGTYPE;
        krb5_set_error_message(context, ret,
                               "PKINIT failed to decode ECDH key");
        goto out;
    }
    client_params->u.ecdh.public_key = public;
    public = NULL;

 out:
    if (public)
        EC_KEY_free(public);
    free_ECParameters(&ecp);
    return ret;
}

#endif /* HAVE_OPENSSL */

krb5_error_code
_kdc_pk_rd_padata(krb5_context context,
                  krb5_kdc_configuration *config,
                  const KDC_REQ *req,
                  const PA_DATA *pa,
                  hdb_entry_ex *client,
                  pk_client_params **ret_params)
{
    pk_client_params *cp;
    krb5_error_code ret;
    heim_oid eContentType = { 0, NULL }, contentInfoOid = { 0, NULL };
    krb5_data eContent = { 0, NULL };
    krb5_data signed_content = { 0, NULL };
    const char *type = "unknown type";
    hx509_certs trust_anchors;
    int have_data = 0;
    const HDB_Ext_PKINIT_cert *pc;

    *ret_params = NULL;

    if (!config->enable_pkinit) {
        kdc_log(context, config, 0, "PK-INIT request but PK-INIT not enabled");
        krb5_clear_error_message(context);
        return 0;
    }

    cp = calloc(1, sizeof(*cp));
    if (cp == NULL) {
        krb5_clear_error_message(context);
        ret = ENOMEM;
        goto out;
    }

    ret = hx509_certs_init(context->hx509ctx,
                           "MEMORY:trust-anchors",
                           0, NULL, &trust_anchors);
    if (ret) {
        krb5_set_error_message(context, ret, "failed to create trust anchors");
        goto out;
    }

    ret = hx509_certs_merge(context->hx509ctx, trust_anchors,
                            kdc_identity->anchors);
    if (ret) {
        hx509_certs_free(&trust_anchors);
        krb5_set_error_message(context, ret, "failed to create verify context");
        goto out;
    }

    /* Add any registered certificates for this client as trust anchors */
    ret = hdb_entry_get_pkinit_cert(&client->entry, &pc);
    if (ret == 0 && pc != NULL) {
        hx509_cert cert;
        unsigned int i;

        for (i = 0; i < pc->len; i++) {
            ret = hx509_cert_init_data(context->hx509ctx,
                                       pc->val[i].cert.data,
                                       pc->val[i].cert.length,
                                       &cert);
            if (ret)
                continue;
            hx509_certs_add(context->hx509ctx, trust_anchors, cert);
            hx509_cert_free(cert);
        }
    }

    ret = hx509_verify_init_ctx(context->hx509ctx, &cp->verify_ctx);
    if (ret) {
        hx509_certs_free(&trust_anchors);
        krb5_set_error_message(context, ret, "failed to create verify context");
        goto out;
    }

    hx509_verify_set_time(cp->verify_ctx, kdc_time);
    hx509_verify_attach_anchors(cp->verify_ctx, trust_anchors);
    hx509_certs_free(&trust_anchors);

    if (config->pkinit_allow_proxy_certs)
        hx509_verify_set_proxy_certificate(cp->verify_ctx, 1);

    if (pa->padata_type == KRB5_PADATA_PK_AS_REQ_WIN) {
        PA_PK_AS_REQ_Win2k r;

        type = "PK-INIT-Win2k";

        if (req->req_body.kdc_options.request_anonymous) {
            ret = KRB5_KDC_ERR_PUBLIC_KEY_ENCRYPTION_NOT_SUPPORTED;
            krb5_set_error_message(context, ret,
                                   "Anon not supported in RSA mode");
            goto out;
        }

        ret = decode_PA_PK_AS_REQ_Win2k(pa->padata_value.data,
                                        pa->padata_value.length,
                                        &r,
                                        NULL);
        if (ret) {
            krb5_set_error_message(context, ret, "Can't decode "
                                   "PK-AS-REQ-Win2k: %d", ret);
            goto out;
        }

        ret = hx509_cms_unwrap_ContentInfo(&r.signed_auth_pack,
                                           &contentInfoOid,
                                           &signed_content,
                                           &have_data);
        free_PA_PK_AS_REQ_Win2k(&r);
        if (ret) {
            krb5_set_error_message(context, ret,
                                   "Can't unwrap ContentInfo(win): %d", ret);
            goto out;
        }

    } else if (pa->padata_type == KRB5_PADATA_PK_AS_REQ) {
        PA_PK_AS_REQ r;

        type = "PK-INIT-IETF";

        ret = decode_PA_PK_AS_REQ(pa->padata_value.data,
                                  pa->padata_value.length,
                                  &r,
                                  NULL);
        if (ret) {
            krb5_set_error_message(context, ret,
                                   "Can't decode PK-AS-REQ: %d", ret);
            goto out;
        }

        /* XXX look at r.kdcPkId */
        if (r.trustedCertifiers) {
            ExternalPrincipalIdentifiers *edi = r.trustedCertifiers;
            unsigned int i, maxedi;

            ret = hx509_certs_init(context->hx509ctx,
                                   "MEMORY:client-anchors",
                                   0, NULL,
                                   &cp->client_anchors);
            if (ret) {
                krb5_set_error_message(context, ret,
                                       "Can't allocate client anchors: %d",
                                       ret);
                goto out;

            }
            /*
             * If the client sent more then 10 EDI, don't bother
             * looking more then 10 of performance reasons.
             */
            maxedi = edi->len;
            if (maxedi > 10)
                maxedi = 10;
            for (i = 0; i < maxedi; i++) {
                IssuerAndSerialNumber iasn;
                hx509_query *q;
                hx509_cert cert;
                size_t size;

                if (edi->val[i].issuerAndSerialNumber == NULL)
                    continue;

                ret = hx509_query_alloc(context->hx509ctx, &q);
                if (ret) {
                    krb5_set_error_message(context, ret,
                                          "Failed to allocate hx509_query");
                    goto out;
                }

                ret = decode_IssuerAndSerialNumber(edi->val[i].issuerAndSerialNumber->data,
                                                   edi->val[i].issuerAndSerialNumber->length,
                                                   &iasn,
                                                   &size);
                if (ret) {
                    hx509_query_free(context->hx509ctx, q);
                    continue;
                }
                ret = hx509_query_match_issuer_serial(q, &iasn.issuer, &iasn.serialNumber);
                free_IssuerAndSerialNumber(&iasn);
                if (ret) {
                    hx509_query_free(context->hx509ctx, q);
                    continue;
                }

                ret = hx509_certs_find(context->hx509ctx,
                                       kdc_identity->certs,
                                       q,
                                       &cert);
                hx509_query_free(context->hx509ctx, q);
                if (ret)
                    continue;
                hx509_certs_add(context->hx509ctx,
                                cp->client_anchors, cert);
                hx509_cert_free(cert);
            }
        }

        ret = hx509_cms_unwrap_ContentInfo(&r.signedAuthPack,
                                           &contentInfoOid,
                                           &signed_content,
                                           &have_data);
        free_PA_PK_AS_REQ(&r);
        if (ret) {
            krb5_set_error_message(context, ret,
                                   "Can't unwrap ContentInfo: %d", ret);
            goto out;
        }

    } else {
        krb5_clear_error_message(context);
        ret = KRB5KDC_ERR_PADATA_TYPE_NOSUPP;
        goto out;
    }

    ret = der_heim_oid_cmp(&contentInfoOid, &asn1_oid_id_pkcs7_signedData);
    if (ret != 0) {
        ret = KRB5KRB_ERR_GENERIC;
        krb5_set_error_message(context, ret,
                               "PK-AS-REQ-Win2k invalid content type oid");
        goto out;
    }

    if (!have_data) {
        ret = KRB5KRB_ERR_GENERIC;
        krb5_set_error_message(context, ret,
                              "PK-AS-REQ-Win2k no signed auth pack");
        goto out;
    }

    {
        hx509_certs signer_certs;
        int flags = HX509_CMS_VS_ALLOW_DATA_OID_MISMATCH; /* BTMM */

        if (req->req_body.kdc_options.request_anonymous)
            flags |= HX509_CMS_VS_ALLOW_ZERO_SIGNER;

        ret = hx509_cms_verify_signed(context->hx509ctx,
                                      cp->verify_ctx,
                                      flags,
                                      signed_content.data,
                                      signed_content.length,
                                      NULL,
                                      kdc_identity->certpool,
                                      &eContentType,
                                      &eContent,
                                      &signer_certs);
        if (ret) {
            char *s = hx509_get_error_string(context->hx509ctx, ret);
            krb5_warnx(context, "PKINIT: failed to verify signature: %s: %d",
                       s, ret);
            free(s);
            goto out;
        }

        if (signer_certs) {
            ret = hx509_get_one_cert(context->hx509ctx, signer_certs,
                                     &cp->cert);
            hx509_certs_free(&signer_certs);
        }
        if (ret)
            goto out;
    }

    /* Signature is correct, now verify the signed message */
    if (der_heim_oid_cmp(&eContentType, &asn1_oid_id_pkcs7_data) != 0 &&
        der_heim_oid_cmp(&eContentType, &asn1_oid_id_pkauthdata) != 0)
    {
        ret = KRB5_BADMSGTYPE;
        krb5_set_error_message(context, ret, "got wrong oid for pkauthdata");
        goto out;
    }

    if (pa->padata_type == KRB5_PADATA_PK_AS_REQ_WIN) {
        AuthPack_Win2k ap;

        ret = decode_AuthPack_Win2k(eContent.data,
                                    eContent.length,
                                    &ap,
                                    NULL);
        if (ret) {
            krb5_set_error_message(context, ret,
                                   "Can't decode AuthPack: %d", ret);
            goto out;
        }

        ret = pk_check_pkauthenticator_win2k(context,
                                             &ap.pkAuthenticator,
                                             req);
        if (ret) {
            free_AuthPack_Win2k(&ap);
            goto out;
        }

        cp->type = PKINIT_WIN2K;
        cp->nonce = ap.pkAuthenticator.nonce;

        if (ap.clientPublicValue) {
            ret = KRB5KRB_ERR_GENERIC;
            krb5_set_error_message(context, ret,
                                   "DH not supported for windows");
            goto out;
        }
        free_AuthPack_Win2k(&ap);

    } else if (pa->padata_type == KRB5_PADATA_PK_AS_REQ) {
        AuthPack ap;

        ret = decode_AuthPack(eContent.data,
                              eContent.length,
                              &ap,
                              NULL);
        if (ret) {
            krb5_set_error_message(context, ret,
                                   "Can't decode AuthPack: %d", ret);
            free_AuthPack(&ap);
            goto out;
        }

        if (req->req_body.kdc_options.request_anonymous &&
            ap.clientPublicValue == NULL) {
            free_AuthPack(&ap);
            ret = KRB5_KDC_ERR_PUBLIC_KEY_ENCRYPTION_NOT_SUPPORTED;
            krb5_set_error_message(context, ret,
                                   "Anon not supported in RSA mode");
            goto out;
        }

        ret = pk_check_pkauthenticator(context,
                                       &ap.pkAuthenticator,
                                       req);
        if (ret) {
            free_AuthPack(&ap);
            goto out;
        }

        cp->type = PKINIT_27;
        cp->nonce = ap.pkAuthenticator.nonce;

        if (ap.clientPublicValue) {
            if (der_heim_oid_cmp(&ap.clientPublicValue->algorithm.algorithm, &asn1_oid_id_dhpublicnumber) == 0) {
                cp->keyex = USE_DH;
                ret = get_dh_param(context, config,
                                   ap.clientPublicValue, cp);
#ifdef HAVE_OPENSSL
            } else if (der_heim_oid_cmp(&ap.clientPublicValue->algorithm.algorithm, &asn1_oid_id_ecPublicKey) == 0) {
                cp->keyex = USE_ECDH;
                ret = get_ecdh_param(context, config,
                                     ap.clientPublicValue, cp);
#endif /* HAVE_OPENSSL */
            } else {
                ret = KRB5_BADMSGTYPE;
                krb5_set_error_message(context, ret, "PKINIT unknown DH mechanism");
            }
            if (ret) {
                free_AuthPack(&ap);
                goto out;
            }
        } else
            cp->keyex = USE_RSA;

        ret = hx509_peer_info_alloc(context->hx509ctx,
                                        &cp->peer);
        if (ret) {
            free_AuthPack(&ap);
            goto out;
        }

        if (ap.supportedCMSTypes) {
            ret = hx509_peer_info_set_cms_algs(context->hx509ctx,
                                               cp->peer,
                                               ap.supportedCMSTypes->val,
                                               ap.supportedCMSTypes->len);
            if (ret) {
                free_AuthPack(&ap);
                goto out;
            }
        } else {
            /* assume old client */
            hx509_peer_info_add_cms_alg(context->hx509ctx, cp->peer,
                                        hx509_crypto_des_rsdi_ede3_cbc());
            hx509_peer_info_add_cms_alg(context->hx509ctx, cp->peer,
                                        hx509_signature_rsa_with_sha1());
            hx509_peer_info_add_cms_alg(context->hx509ctx, cp->peer,
                                        hx509_signature_sha1());
        }
        free_AuthPack(&ap);
    } else
        krb5_abortx(context, "internal pkinit error");

    kdc_log(context, config, 0, "PK-INIT request of type %s", type);

out:
    if (ret)
        krb5_warn(context, ret, "PKINIT");

    if (signed_content.data)
        free(signed_content.data);
    krb5_data_free(&eContent);
    der_free_oid(&eContentType);
    der_free_oid(&contentInfoOid);
    if (ret) {
        _kdc_pk_free_client_param(context, cp);
    } else
        *ret_params = cp;
    return ret;
}

/*
 *
 */

static krb5_error_code
BN_to_integer(krb5_context context, const BIGNUM *bn, heim_integer *integer)
{
    integer->length = BN_num_bytes(bn);
    integer->data = malloc(integer->length);
    if (integer->data == NULL) {
        krb5_clear_error_message(context);
        return ENOMEM;
    }
    BN_bn2bin(bn, integer->data);
    integer->negative = BN_is_negative(bn);
    return 0;
}

static krb5_error_code
pk_mk_pa_reply_enckey(krb5_context context,
                      krb5_kdc_configuration *config,
                      pk_client_params *cp,
                      const KDC_REQ *req,
                      const krb5_data *req_buffer,
                      krb5_keyblock *reply_key,
                      ContentInfo *content_info,
                      hx509_cert *kdc_cert)
{
    const heim_oid *envelopedAlg = NULL, *sdAlg = NULL, *evAlg = NULL;
    krb5_error_code ret;
    krb5_data buf, signed_data;
    size_t size = 0;
    int do_win2k = 0;

    krb5_data_zero(&buf);
    krb5_data_zero(&signed_data);

    *kdc_cert = NULL;

    /*
     * If the message client is a win2k-type but it send pa data
     * 09-binding it expects a IETF (checksum) reply so there can be
     * no replay attacks.
     */

    switch (cp->type) {
    case PKINIT_WIN2K: {
        int i = 0;
        if (_kdc_find_padata(req, &i, KRB5_PADATA_PK_AS_09_BINDING) == NULL
            && config->pkinit_require_binding == 0)
        {
            do_win2k = 1;
        }
        sdAlg = &asn1_oid_id_pkcs7_data;
        evAlg = &asn1_oid_id_pkcs7_data;
        envelopedAlg = &asn1_oid_id_rsadsi_des_ede3_cbc;
        break;
    }
    case PKINIT_27:
        sdAlg = &asn1_oid_id_pkrkeydata;
        evAlg = &asn1_oid_id_pkcs7_signedData;
        break;
    default:
        krb5_abortx(context, "internal pkinit error");
    }

    if (do_win2k) {
        ReplyKeyPack_Win2k kp;
        memset(&kp, 0, sizeof(kp));

        ret = copy_EncryptionKey(reply_key, &kp.replyKey);
        if (ret) {
            krb5_clear_error_message(context);
            goto out;
        }
        kp.nonce = cp->nonce;

        ASN1_MALLOC_ENCODE(ReplyKeyPack_Win2k,
                           buf.data, buf.length,
                           &kp, &size,ret);
        free_ReplyKeyPack_Win2k(&kp);
    } else {
        krb5_crypto ascrypto;
        ReplyKeyPack kp;
        memset(&kp, 0, sizeof(kp));

        ret = copy_EncryptionKey(reply_key, &kp.replyKey);
        if (ret) {
            krb5_clear_error_message(context);
            goto out;
        }

        ret = krb5_crypto_init(context, reply_key, 0, &ascrypto);
        if (ret) {
            krb5_clear_error_message(context);
            goto out;
        }

        ret = krb5_create_checksum(context, ascrypto, 6, 0,
                                   req_buffer->data, req_buffer->length,
                                   &kp.asChecksum);
        if (ret) {
            krb5_clear_error_message(context);
            goto out;
        }

        ret = krb5_crypto_destroy(context, ascrypto);
        if (ret) {
            krb5_clear_error_message(context);
            goto out;
        }
        ASN1_MALLOC_ENCODE(ReplyKeyPack, buf.data, buf.length, &kp, &size,ret);
        free_ReplyKeyPack(&kp);
    }
    if (ret) {
        krb5_set_error_message(context, ret, "ASN.1 encoding of ReplyKeyPack "
                               "failed (%d)", ret);
        goto out;
    }
    if (buf.length != size)
        krb5_abortx(context, "Internal ASN.1 encoder error");

    {
        hx509_query *q;
        hx509_cert cert;

        ret = hx509_query_alloc(context->hx509ctx, &q);
        if (ret)
            goto out;

        hx509_query_match_option(q, HX509_QUERY_OPTION_PRIVATE_KEY);
        if (config->pkinit_kdc_friendly_name)
            hx509_query_match_friendly_name(q, config->pkinit_kdc_friendly_name);

        ret = hx509_certs_find(context->hx509ctx,
                               kdc_identity->certs,
                               q,
                               &cert);
        hx509_query_free(context->hx509ctx, q);
        if (ret)
            goto out;

        ret = hx509_cms_create_signed_1(context->hx509ctx,
                                        0,
                                        sdAlg,
                                        buf.data,
                                        buf.length,
                                        NULL,
                                        cert,
                                        cp->peer,
                                        cp->client_anchors,
                                        kdc_identity->certpool,
                                        &signed_data);
        *kdc_cert = cert;
    }

    krb5_data_free(&buf);
    if (ret)
        goto out;

    if (cp->type == PKINIT_WIN2K) {
        ret = hx509_cms_wrap_ContentInfo(&asn1_oid_id_pkcs7_signedData,
                                         &signed_data,
                                         &buf);
        if (ret)
            goto out;
        krb5_data_free(&signed_data);
        signed_data = buf;
    }

    ret = hx509_cms_envelope_1(context->hx509ctx,
                               HX509_CMS_EV_NO_KU_CHECK,
                               cp->cert,
                               signed_data.data, signed_data.length,
                               envelopedAlg,
                               evAlg, &buf);
    if (ret)
        goto out;

    ret = _krb5_pk_mk_ContentInfo(context,
                                  &buf,
                                  &asn1_oid_id_pkcs7_envelopedData,
                                  content_info);
out:
    if (ret && *kdc_cert) {
        hx509_cert_free(*kdc_cert);
        *kdc_cert = NULL;
    }

    krb5_data_free(&buf);
    krb5_data_free(&signed_data);
    return ret;
}

/*
 *
 */

static krb5_error_code
pk_mk_pa_reply_dh(krb5_context context,
                  krb5_kdc_configuration *config,
                  pk_client_params *cp,
                  ContentInfo *content_info,
                  hx509_cert *kdc_cert)
{
    KDCDHKeyInfo dh_info;
    krb5_data signed_data, buf;
    ContentInfo contentinfo;
    krb5_error_code ret;
    hx509_cert cert;
    hx509_query *q;
    size_t size = 0;

    memset(&contentinfo, 0, sizeof(contentinfo));
    memset(&dh_info, 0, sizeof(dh_info));
    krb5_data_zero(&signed_data);
    krb5_data_zero(&buf);

    *kdc_cert = NULL;

    if (cp->keyex == USE_DH) {
        DH *kdc_dh = cp->u.dh.key;
        const BIGNUM *pub_key;
        heim_integer i;

        DH_get0_key(kdc_dh, &pub_key, NULL);
        ret = BN_to_integer(context, pub_key, &i);
        if (ret)
            return ret;

        ASN1_MALLOC_ENCODE(DHPublicKey, buf.data, buf.length, &i, &size, ret);
        der_free_heim_integer(&i);
        if (ret) {
            krb5_set_error_message(context, ret, "ASN.1 encoding of "
                                   "DHPublicKey failed (%d)", ret);
            return ret;
        }
        if (buf.length != size)
            krb5_abortx(context, "Internal ASN.1 encoder error");

        dh_info.subjectPublicKey.length = buf.length * 8;
        dh_info.subjectPublicKey.data = buf.data;
        krb5_data_zero(&buf);
#ifdef HAVE_OPENSSL
    } else if (cp->keyex == USE_ECDH) {
        unsigned char *p;
        int len;

        len = i2o_ECPublicKey(cp->u.ecdh.key, NULL);
        if (len <= 0)
            abort();

        p = malloc(len);
        if (p == NULL)
            abort();

        dh_info.subjectPublicKey.length = len * 8;
        dh_info.subjectPublicKey.data = p;

        len = i2o_ECPublicKey(cp->u.ecdh.key, &p);
        if (len <= 0)
            abort();
#endif
    } else
        krb5_abortx(context, "no keyex selected ?");


    dh_info.nonce = cp->nonce;

    ASN1_MALLOC_ENCODE(KDCDHKeyInfo, buf.data, buf.length, &dh_info, &size,
                       ret);
    if (ret) {
        krb5_set_error_message(context, ret, "ASN.1 encoding of "
                               "KdcDHKeyInfo failed (%d)", ret);
        goto out;
    }
    if (buf.length != size)
        krb5_abortx(context, "Internal ASN.1 encoder error");

    /*
     * Create the SignedData structure and sign the KdcDHKeyInfo
     * filled in above
     */

    ret = hx509_query_alloc(context->hx509ctx, &q);
    if (ret)
        goto out;

    hx509_query_match_option(q, HX509_QUERY_OPTION_PRIVATE_KEY);
    if (config->pkinit_kdc_friendly_name)
        hx509_query_match_friendly_name(q, config->pkinit_kdc_friendly_name);

    ret = hx509_certs_find(context->hx509ctx,
                           kdc_identity->certs,
                           q,
                           &cert);
    hx509_query_free(context->hx509ctx, q);
    if (ret)
        goto out;

    ret = hx509_cms_create_signed_1(context->hx509ctx,
                                    0,
                                    &asn1_oid_id_pkdhkeydata,
                                    buf.data,
                                    buf.length,
                                    NULL,
                                    cert,
                                    cp->peer,
                                    cp->client_anchors,
                                    kdc_identity->certpool,
                                    &signed_data);
    if (ret) {
        kdc_log(context, config, 0, "Failed signing the DH* reply: %d", ret);
        goto out;
    }
    *kdc_cert = cert;

    ret = _krb5_pk_mk_ContentInfo(context,
                                  &signed_data,
                                  &asn1_oid_id_pkcs7_signedData,
                                  content_info);
    if (ret)
        goto out;

 out:
    if (ret && *kdc_cert) {
        hx509_cert_free(*kdc_cert);
        *kdc_cert = NULL;
    }

    krb5_data_free(&buf);
    krb5_data_free(&signed_data);
    free_KDCDHKeyInfo(&dh_info);

    return ret;
}

/*
 *
 */

krb5_error_code
_kdc_pk_mk_pa_reply(krb5_context context,
                    krb5_kdc_configuration *config,
                    pk_client_params *cp,
                    const hdb_entry_ex *client,
                    krb5_enctype sessionetype,
                    const KDC_REQ *req,
                    const krb5_data *req_buffer,
                    krb5_keyblock **reply_key,
                    krb5_keyblock *sessionkey,
                    METHOD_DATA *md)
{
    krb5_error_code ret;
    void *buf = NULL;
    size_t len = 0, size = 0;
    krb5_enctype enctype;
    int pa_type;
    hx509_cert kdc_cert = NULL;
    size_t i;

    if (!config->enable_pkinit) {
        krb5_clear_error_message(context);
        return 0;
    }

    if (req->req_body.etype.len > 0) {
        for (i = 0; i < req->req_body.etype.len; i++)
            if (krb5_enctype_valid(context, req->req_body.etype.val[i]) == 0)
                break;
        if (req->req_body.etype.len <= i) {
            ret = KRB5KRB_ERR_GENERIC;
            krb5_set_error_message(context, ret,
                                   "No valid enctype available from client");
            goto out;
        }
        enctype = req->req_body.etype.val[i];
    } else
        enctype = ETYPE_DES3_CBC_SHA1;

    if (cp->type == PKINIT_27) {
        PA_PK_AS_REP rep;
        const char *type, *other = "";

        memset(&rep, 0, sizeof(rep));

        pa_type = KRB5_PADATA_PK_AS_REP;

        if (cp->keyex == USE_RSA) {
            ContentInfo info;

            type = "enckey";

            rep.element = choice_PA_PK_AS_REP_encKeyPack;

            ret = krb5_generate_random_keyblock(context, enctype,
                                                &cp->reply_key);
            if (ret) {
                free_PA_PK_AS_REP(&rep);
                goto out;
            }
            ret = pk_mk_pa_reply_enckey(context,
                                        config,
                                        cp,
                                        req,
                                        req_buffer,
                                        &cp->reply_key,
                                        &info,
                                        &kdc_cert);
            if (ret) {
                free_PA_PK_AS_REP(&rep);
                goto out;
            }
            ASN1_MALLOC_ENCODE(ContentInfo, rep.u.encKeyPack.data,
                               rep.u.encKeyPack.length, &info, &size,
                               ret);
            free_ContentInfo(&info);
            if (ret) {
                krb5_set_error_message(context, ret, "encoding of Key ContentInfo "
                                       "failed %d", ret);
                free_PA_PK_AS_REP(&rep);
                goto out;
            }
            if (rep.u.encKeyPack.length != size)
                krb5_abortx(context, "Internal ASN.1 encoder error");

            ret = krb5_generate_random_keyblock(context, sessionetype,
                                                sessionkey);
            if (ret) {
                free_PA_PK_AS_REP(&rep);
                goto out;
            }

        } else {
            ContentInfo info;

            switch (cp->keyex) {
            case USE_DH: type = "dh"; break;
#ifdef HAVE_OPENSSL
            case USE_ECDH: type = "ecdh"; break;
#endif
            default: krb5_abortx(context, "unknown keyex"); break;
            }

            if (cp->dh_group_name)
                other = cp->dh_group_name;

            rep.element = choice_PA_PK_AS_REP_dhInfo;

            ret = generate_dh_keyblock(context, cp, enctype);
            if (ret)
                return ret;

            ret = pk_mk_pa_reply_dh(context, config,
                                    cp,
                                    &info,
                                    &kdc_cert);
            if (ret) {
                free_PA_PK_AS_REP(&rep);
                krb5_set_error_message(context, ret,
                                       "create pa-reply-dh "
                                       "failed %d", ret);
                goto out;
            }

            ASN1_MALLOC_ENCODE(ContentInfo, rep.u.dhInfo.dhSignedData.data,
                               rep.u.dhInfo.dhSignedData.length, &info, &size,
                               ret);
            free_ContentInfo(&info);
            if (ret) {
                krb5_set_error_message(context, ret,
                                       "encoding of Key ContentInfo "
                                       "failed %d", ret);
                free_PA_PK_AS_REP(&rep);
                goto out;
            }
            if (rep.u.encKeyPack.length != size)
                krb5_abortx(context, "Internal ASN.1 encoder error");

            /* XXX KRB-FX-CF2 */
            ret = krb5_generate_random_keyblock(context, sessionetype,
                                                sessionkey);
            if (ret) {
                free_PA_PK_AS_REP(&rep);
                goto out;
            }

            /* XXX Add PA-PKINIT-KX */

        }

#define use_btmm_with_enckey 0
        if (use_btmm_with_enckey && rep.element == choice_PA_PK_AS_REP_encKeyPack) {
            PA_PK_AS_REP_BTMM btmm;
            heim_any any;

            any.data = rep.u.encKeyPack.data;
            any.length = rep.u.encKeyPack.length;

            btmm.dhSignedData = NULL;
            btmm.encKeyPack = &any;

            ASN1_MALLOC_ENCODE(PA_PK_AS_REP_BTMM, buf, len, &btmm, &size, ret);
        } else {
            ASN1_MALLOC_ENCODE(PA_PK_AS_REP, buf, len, &rep, &size, ret);
        }

        free_PA_PK_AS_REP(&rep);
        if (ret) {
            krb5_set_error_message(context, ret,
                                   "encode PA-PK-AS-REP failed %d", ret);
            goto out;
        }
        if (len != size)
            krb5_abortx(context, "Internal ASN.1 encoder error");

        kdc_log(context, config, 0, "PK-INIT using %s %s", type, other);

    } else if (cp->type == PKINIT_WIN2K) {
        PA_PK_AS_REP_Win2k rep;
        ContentInfo info;

        if (cp->keyex != USE_RSA) {
            ret = KRB5KRB_ERR_GENERIC;
            krb5_set_error_message(context, ret,
                                   "Windows PK-INIT doesn't support DH");
            goto out;
        }

        memset(&rep, 0, sizeof(rep));

        pa_type = KRB5_PADATA_PK_AS_REP_19;
        rep.element = choice_PA_PK_AS_REP_Win2k_encKeyPack;

        ret = krb5_generate_random_keyblock(context, enctype,
                                            &cp->reply_key);
        if (ret) {
            free_PA_PK_AS_REP_Win2k(&rep);
            goto out;
        }
        ret = pk_mk_pa_reply_enckey(context,
                                    config,
                                    cp,
                                    req,
                                    req_buffer,
                                    &cp->reply_key,
                                    &info,
                                    &kdc_cert);
        if (ret) {
            free_PA_PK_AS_REP_Win2k(&rep);
            goto out;
        }
        ASN1_MALLOC_ENCODE(ContentInfo, rep.u.encKeyPack.data,
                           rep.u.encKeyPack.length, &info, &size,
                           ret);
        free_ContentInfo(&info);
        if (ret) {
            krb5_set_error_message(context, ret, "encoding of Key ContentInfo "
                                  "failed %d", ret);
            free_PA_PK_AS_REP_Win2k(&rep);
            goto out;
        }
        if (rep.u.encKeyPack.length != size)
            krb5_abortx(context, "Internal ASN.1 encoder error");

        ASN1_MALLOC_ENCODE(PA_PK_AS_REP_Win2k, buf, len, &rep, &size, ret);
        free_PA_PK_AS_REP_Win2k(&rep);
        if (ret) {
            krb5_set_error_message(context, ret,
                                  "encode PA-PK-AS-REP-Win2k failed %d", ret);
            goto out;
        }
        if (len != size)
            krb5_abortx(context, "Internal ASN.1 encoder error");

        ret = krb5_generate_random_keyblock(context, sessionetype,
                                            sessionkey);
        if (ret) {
            free(buf);
            goto out;
        }

    } else
        krb5_abortx(context, "PK-INIT internal error");


    ret = krb5_padata_add(context, md, pa_type, buf, len);
    if (ret) {
        krb5_set_error_message(context, ret,
                               "Failed adding PA-PK-AS-REP %d", ret);
        free(buf);
        goto out;
    }

    if (config->pkinit_kdc_ocsp_file) {

        if (ocsp.expire == 0 && ocsp.next_update > kdc_time) {
            struct stat sb;
            int fd;

            krb5_data_free(&ocsp.data);

            ocsp.expire = 0;
            ocsp.next_update = kdc_time + 60 * 5;

            fd = open(config->pkinit_kdc_ocsp_file, O_RDONLY);
            if (fd < 0) {
                kdc_log(context, config, 0,
                        "PK-INIT failed to open ocsp data file %d", errno);
                goto out_ocsp;
            }
            ret = fstat(fd, &sb);
            if (ret) {
                ret = errno;
                close(fd);
                kdc_log(context, config, 0,
                        "PK-INIT failed to stat ocsp data %d", ret);
                goto out_ocsp;
            }

            ret = krb5_data_alloc(&ocsp.data, sb.st_size);
            if (ret) {
                close(fd);
                kdc_log(context, config, 0,
                        "PK-INIT failed to stat ocsp data %d", ret);
                goto out_ocsp;
            }
            ocsp.data.length = sb.st_size;
            ret = read(fd, ocsp.data.data, sb.st_size);
            close(fd);
            if (ret != sb.st_size) {
                kdc_log(context, config, 0,
                        "PK-INIT failed to read ocsp data %d", errno);
                goto out_ocsp;
            }

            ret = hx509_ocsp_verify(context->hx509ctx,
                                    kdc_time,
                                    kdc_cert,
                                    0,
                                    ocsp.data.data, ocsp.data.length,
                                    &ocsp.expire);
            if (ret) {
                kdc_log(context, config, 0,
                        "PK-INIT failed to verify ocsp data %d", ret);
                krb5_data_free(&ocsp.data);
                ocsp.expire = 0;
            } else if (ocsp.expire > 180) {
                ocsp.expire -= 180; /* refetch the ocsp before it expire */
                ocsp.next_update = ocsp.expire;
            } else {
                ocsp.next_update = kdc_time;
            }
        out_ocsp:
            ret = 0;
        }

        if (ocsp.expire != 0 && ocsp.expire > kdc_time) {

            ret = krb5_padata_add(context, md,
                                  KRB5_PADATA_PA_PK_OCSP_RESPONSE,
                                  ocsp.data.data, ocsp.data.length);
            if (ret) {
                krb5_set_error_message(context, ret,
                                       "Failed adding OCSP response %d", ret);
                goto out;
            }
        }
    }

out:
    if (kdc_cert)
        hx509_cert_free(kdc_cert);

    if (ret == 0)
        *reply_key = &cp->reply_key;
    return ret;
}

static int
match_rfc_san(krb5_context context,
              krb5_kdc_configuration *config,
              hx509_context hx509ctx,
              hx509_cert client_cert,
              krb5_const_principal match)
{
    hx509_octet_string_list list;
    int ret, found = 0;
    size_t i;

    memset(&list, 0 , sizeof(list));

    ret = hx509_cert_find_subjectAltName_otherName(hx509ctx,
                                                   client_cert,
                                                   &asn1_oid_id_pkinit_san,
                                                   &list);
    if (ret)
        goto out;

    for (i = 0; !found && i < list.len; i++) {
        krb5_principal_data principal;
        KRB5PrincipalName kn;
        size_t size;

        ret = decode_KRB5PrincipalName(list.val[i].data,
                                       list.val[i].length,
                                       &kn, &size);
        if (ret) {
            const char *msg = krb5_get_error_message(context, ret);
            kdc_log(context, config, 0,
                    "Decoding kerberos name in certificate failed: %s", msg);
            krb5_free_error_message(context, msg);
            break;
        }
        if (size != list.val[i].length) {
            kdc_log(context, config, 0,
                    "Decoding kerberos name have extra bits on the end");
            return KRB5_KDC_ERR_CLIENT_NAME_MISMATCH;
        }

        principal.name = kn.principalName;
        principal.realm = kn.realm;

        if (krb5_principal_compare(context, &principal, match) == TRUE)
            found = 1;
        free_KRB5PrincipalName(&kn);
    }

out:
    hx509_free_octet_string_list(&list);
    if (ret)
        return ret;

    if (!found)
        return KRB5_KDC_ERR_CLIENT_NAME_MISMATCH;

    return 0;
}

static int
match_ms_upn_san(krb5_context context,
                 krb5_kdc_configuration *config,
                 hx509_context hx509ctx,
                 hx509_cert client_cert,
                 HDB *clientdb,
                 hdb_entry_ex *client)
{
    hx509_octet_string_list list;
    krb5_principal principal = NULL;
    int ret;
    MS_UPN_SAN upn;
    size_t size;

    memset(&list, 0 , sizeof(list));

    ret = hx509_cert_find_subjectAltName_otherName(hx509ctx,
                                                   client_cert,
                                                   &asn1_oid_id_pkinit_ms_san,
                                                   &list);
    if (ret)
        goto out;

    if (list.len != 1) {
        kdc_log(context, config, 0,
                "More then one PK-INIT MS UPN SAN");
        goto out;
    }

    ret = decode_MS_UPN_SAN(list.val[0].data, list.val[0].length, &upn, &size);
    if (ret) {
        kdc_log(context, config, 0, "Decode of MS-UPN-SAN failed");
        goto out;
    }
    if (size != list.val[0].length) {
        free_MS_UPN_SAN(&upn);
        kdc_log(context, config, 0, "Trailing data in ");
        ret = KRB5_KDC_ERR_CLIENT_NAME_MISMATCH;
        goto out;
    }

    kdc_log(context, config, 0, "found MS UPN SAN: %s", upn);

    ret = krb5_parse_name(context, upn, &principal);
    free_MS_UPN_SAN(&upn);
    if (ret) {
        kdc_log(context, config, 0, "Failed to parse principal in MS UPN SAN");
        goto out;
    }

    if (clientdb->hdb_check_pkinit_ms_upn_match) {
        ret = clientdb->hdb_check_pkinit_ms_upn_match(context, clientdb, client, principal);
    } else {

        /*
         * This is very wrong, but will do for a fallback
         */
        strupr(principal->realm);

        if (krb5_principal_compare(context, principal, client->entry.principal) == FALSE)
            ret = KRB5_KDC_ERR_CLIENT_NAME_MISMATCH;
    }

out:
    if (principal)
        krb5_free_principal(context, principal);
    hx509_free_octet_string_list(&list);

    return ret;
}

krb5_error_code
_kdc_pk_check_client(krb5_context context,
                     krb5_kdc_configuration *config,
                     HDB *clientdb,
                     hdb_entry_ex *client,
                     pk_client_params *cp,
                     char **subject_name)
{
    const HDB_Ext_PKINIT_acl *acl;
    const HDB_Ext_PKINIT_cert *pc;
    krb5_error_code ret;
    hx509_name name;
    size_t i;

    if (cp->cert == NULL) {

        *subject_name = strdup("anonymous client client");
        if (*subject_name == NULL)
            return ENOMEM;
        return 0;
    }

    ret = hx509_cert_get_base_subject(context->hx509ctx,
                                      cp->cert,
                                      &name);
    if (ret)
        return ret;

    ret = hx509_name_to_string(name, subject_name);
    hx509_name_free(&name);
    if (ret)
        return ret;

    kdc_log(context, config, 0,
            "Trying to authorize PK-INIT subject DN %s",
            *subject_name);

    ret = hdb_entry_get_pkinit_cert(&client->entry, &pc);
    if (ret == 0 && pc) {
        hx509_cert cert;
        size_t j;

        for (j = 0; j < pc->len; j++) {
            ret = hx509_cert_init_data(context->hx509ctx,
                                       pc->val[j].cert.data,
                                       pc->val[j].cert.length,
                                       &cert);
            if (ret)
                continue;
            ret = hx509_cert_cmp(cert, cp->cert);
            hx509_cert_free(cert);
            if (ret == 0) {
                kdc_log(context, config, 5,
                        "Found matching PK-INIT cert in hdb");
                return 0;
            }
        }
    }


    if (config->pkinit_princ_in_cert) {
        ret = match_rfc_san(context, config,
                            context->hx509ctx,
                            cp->cert,
                            client->entry.principal);
        if (ret == 0) {
            kdc_log(context, config, 5,
                    "Found matching PK-INIT SAN in certificate");
            return 0;
        }
        ret = match_ms_upn_san(context, config,
                               context->hx509ctx,
                               cp->cert,
                               clientdb,
                               client);
        if (ret == 0) {
            kdc_log(context, config, 5,
                    "Found matching MS UPN SAN in certificate");
            return 0;
        }
    }

    ret = hdb_entry_get_pkinit_acl(&client->entry, &acl);
    if (ret == 0 && acl != NULL) {
        /*
         * Cheat here and compare the generated name with the string
         * and not the reverse.
         */
        for (i = 0; i < acl->len; i++) {
            if (strcmp(*subject_name, acl->val[0].subject) != 0)
                continue;

            /* Don't support isser and anchor checking right now */
            if (acl->val[0].issuer)
                continue;
            if (acl->val[0].anchor)
                continue;

            kdc_log(context, config, 5,
                    "Found matching PK-INIT database ACL");
            return 0;
        }
    }

    for (i = 0; i < principal_mappings.len; i++) {
        krb5_boolean b;

        b = krb5_principal_compare(context,
                                   client->entry.principal,
                                   principal_mappings.val[i].principal);
        if (b == FALSE)
            continue;
        if (strcmp(principal_mappings.val[i].subject, *subject_name) != 0)
            continue;
        kdc_log(context, config, 5,
                "Found matching PK-INIT FILE ACL");
        return 0;
    }

    ret = KRB5_KDC_ERR_CLIENT_NAME_MISMATCH;
    krb5_set_error_message(context, ret,
                          "PKINIT no matching principals for %s",
                          *subject_name);

    kdc_log(context, config, 5,
            "PKINIT no matching principals for %s",
            *subject_name);

    free(*subject_name);
    *subject_name = NULL;

    return ret;
}

static krb5_error_code
add_principal_mapping(krb5_context context,
                      const char *principal_name,
                      const char * subject)
{
   struct pk_allowed_princ *tmp;
   krb5_principal principal;
   krb5_error_code ret;

   tmp = realloc(principal_mappings.val,
                 (principal_mappings.len + 1) * sizeof(*tmp));
   if (tmp == NULL)
       return ENOMEM;
   principal_mappings.val = tmp;

   ret = krb5_parse_name(context, principal_name, &principal);
   if (ret)
       return ret;

   principal_mappings.val[principal_mappings.len].principal = principal;

   principal_mappings.val[principal_mappings.len].subject = strdup(subject);
   if (principal_mappings.val[principal_mappings.len].subject == NULL) {
       krb5_free_principal(context, principal);
       return ENOMEM;
   }
   principal_mappings.len++;

   return 0;
}

krb5_error_code
_kdc_add_inital_verified_cas(krb5_context context,
                             krb5_kdc_configuration *config,
                             pk_client_params *cp,
                             EncTicketPart *tkt)
{
    AD_INITIAL_VERIFIED_CAS cas;
    krb5_error_code ret;
    krb5_data data;
    size_t size = 0;

    memset(&cas, 0, sizeof(cas));

    /* XXX add CAs to cas here */

    ASN1_MALLOC_ENCODE(AD_INITIAL_VERIFIED_CAS, data.data, data.length,
                       &cas, &size, ret);
    if (ret)
        return ret;
    if (data.length != size)
        krb5_abortx(context, "internal asn.1 encoder error");

    ret = _kdc_tkt_add_if_relevant_ad(context, tkt,
                                      KRB5_AUTHDATA_INITIAL_VERIFIED_CAS,
                                      &data);
    krb5_data_free(&data);
    return ret;
}

/*
 *
 */

static void
load_mappings(krb5_context context, const char *fn)
{
    krb5_error_code ret;
    char buf[1024];
    unsigned long lineno = 0;
    FILE *f;

    f = fopen(fn, "r");
    if (f == NULL)
        return;

    while (fgets(buf, sizeof(buf), f) != NULL) {
        char *subject_name, *p;

        buf[strcspn(buf, "\n")] = '\0';
        lineno++;

        p = buf + strspn(buf, " \t");

        if (*p == '#' || *p == '\0')
            continue;

        subject_name = strchr(p, ':');
        if (subject_name == NULL) {
            krb5_warnx(context, "pkinit mapping file line %lu "
                       "missing \":\" :%s",
                       lineno, buf);
            continue;
        }
        *subject_name++ = '\0';

        ret = add_principal_mapping(context, p, subject_name);
        if (ret) {
            krb5_warn(context, ret, "failed to add line %lu \":\" :%s\n",
                      lineno, buf);
            continue;
        }
    }

    fclose(f);
}

/*
 *
 */

krb5_error_code
krb5_kdc_pk_initialize(krb5_context context,
                       krb5_kdc_configuration *config,
                       const char *user_id,
                       const char *anchors,
                       char **pool,
                       char **revoke_list)
{
    const char *file;
    char *fn = NULL;
    krb5_error_code ret;

    file = krb5_config_get_string(context, NULL,
                                  "libdefaults", "moduli", NULL);

    ret = _krb5_parse_moduli(context, file, &moduli);
    if (ret)
        krb5_err(context, 1, ret, "PKINIT: failed to load modidi file");

    principal_mappings.len = 0;
    principal_mappings.val = NULL;

    ret = _krb5_pk_load_id(context,
                           &kdc_identity,
                           user_id,
                           anchors,
                           pool,
                           revoke_list,
                           NULL,
                           NULL,
                           NULL);
    if (ret) {
        krb5_warn(context, ret, "PKINIT: ");
        config->enable_pkinit = 0;
        return ret;
    }

    {
        hx509_query *q;
        hx509_cert cert;

        ret = hx509_query_alloc(context->hx509ctx, &q);
        if (ret) {
            krb5_warnx(context, "PKINIT: out of memory");
            return ENOMEM;
        }

        hx509_query_match_option(q, HX509_QUERY_OPTION_PRIVATE_KEY);
        if (config->pkinit_kdc_friendly_name)
            hx509_query_match_friendly_name(q, config->pkinit_kdc_friendly_name);

        ret = hx509_certs_find(context->hx509ctx,
                               kdc_identity->certs,
                               q,
                               &cert);
        hx509_query_free(context->hx509ctx, q);
        if (ret == 0) {
            if (hx509_cert_check_eku(context->hx509ctx, cert,
                                     &asn1_oid_id_pkkdcekuoid, 0)) {
                hx509_name name;
                char *str;
                ret = hx509_cert_get_subject(cert, &name);
                if (ret == 0) {
                    hx509_name_to_string(name, &str);
                    krb5_warnx(context, "WARNING Found KDC certificate (%s)"
                               "is missing the PK-INIT KDC EKU, this is bad for "
                               "interoperability.", str);
                    hx509_name_free(&name);
                    free(str);
                }
            }
            hx509_cert_free(cert);
        } else
            krb5_warnx(context, "PKINIT: failed to find a signing "
                       "certifiate with a public key");
    }

    if (krb5_config_get_bool_default(context,
                                     NULL,
                                     FALSE,
                                     "kdc",
                                     "pkinit_allow_proxy_certificate",
                                     NULL))
        config->pkinit_allow_proxy_certs = 1;

    file = krb5_config_get_string(context,
                                  NULL,
                                  "kdc",
                                  "pkinit_mappings_file",
                                  NULL);
    if (file == NULL) {
        asprintf(&fn, "%s/pki-mapping", hdb_db_dir(context));
        file = fn;
    }

    load_mappings(context, file);
    if (fn)
        free(fn);

    return 0;
}

#endif /* PKINIT */