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;
case USE_ECDH: type = "ecdh"; break;
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");
/* generate the session key using the method from RFC6112 */
{
krb5_keyblock kdc_contribution_key;
krb5_crypto reply_crypto;
krb5_crypto kdccont_crypto;
krb5_data p1 = { strlen("PKINIT"), "PKINIT"};
krb5_data p2 = { strlen("KEYEXCHANGE"), "KEYEXCHANGE"};
void *kckdata;
size_t kcklen;
EncryptedData kx;
void *kxdata;
size_t kxlen;
ret = krb5_generate_random_keyblock(context, sessionetype,
&kdc_contribution_key);
if (ret) {
free_PA_PK_AS_REP(&rep);
goto out;
}
ret = krb5_crypto_init(context, &cp->reply_key, enctype, &reply_crypto);
if (ret) {
krb5_free_keyblock_contents(context, &kdc_contribution_key);
free_PA_PK_AS_REP(&rep);
goto out;
}
ret = krb5_crypto_init(context, &kdc_contribution_key, sessionetype, &kdccont_crypto);
if (ret) {
krb5_crypto_destroy(context, reply_crypto);
krb5_free_keyblock_contents(context, &kdc_contribution_key);
free_PA_PK_AS_REP(&rep);
goto out;
}
/* KRB-FX-CF2 */
ret = krb5_crypto_fx_cf2(context, kdccont_crypto, reply_crypto,
&p1, &p2, sessionetype, sessionkey);
krb5_crypto_destroy(context, kdccont_crypto);
if (ret) {
krb5_crypto_destroy(context, reply_crypto);
krb5_free_keyblock_contents(context, &kdc_contribution_key);
free_PA_PK_AS_REP(&rep);
goto out;
}
ASN1_MALLOC_ENCODE(EncryptionKey, kckdata, kcklen,
&kdc_contribution_key, &size, ret);
krb5_free_keyblock_contents(context, &kdc_contribution_key);
if (ret) {
krb5_set_error_message(context, ret, "encoding of PKINIT-KX Key failed %d", ret);
krb5_crypto_destroy(context, reply_crypto);
free_PA_PK_AS_REP(&rep);
goto out;
}
if (kcklen != size)
krb5_abortx(context, "Internal ASN.1 encoder error");
ret = krb5_encrypt_EncryptedData(context, reply_crypto, KRB5_KU_PA_PKINIT_KX,
kckdata, kcklen, 0, &kx);
krb5_crypto_destroy(context, reply_crypto);
free(kckdata);
if (ret) {
free_PA_PK_AS_REP(&rep);
goto out;
}
ASN1_MALLOC_ENCODE(EncryptedData, kxdata, kxlen,
&kx, &size, ret);
free_EncryptedData(&kx);
if (ret) {
krb5_set_error_message(context, ret, "encoding of PKINIT-KX failed %d", ret);
free_PA_PK_AS_REP(&rep);
goto out;
}
if (kxlen != size)
krb5_abortx(context, "Internal ASN.1 encoder error");
/* Add PA-PKINIT-KX */
ret = krb5_padata_add(context, md, KRB5_PADATA_PKINIT_KX, kxdata, kxlen);
if (ret) {
krb5_set_error_message(context, ret,
"Failed adding PKINIT-KX %d", ret);
free(buf);
goto out;
}
}
}
#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)
ret = krb5_copy_keyblock_contents(context, &cp->reply_key, reply_key);
return ret;
}
krb5_error_code
_kdc_pk_mk_pa_reply(krb5_context context,
krb5_kdc_configuration *config,
pk_client_params *client_params,
const hdb_entry_ex *client,
const KDC_REQ *req,
const krb5_data *req_buffer,
krb5_keyblock **reply_key,
METHOD_DATA *md)
{
krb5_error_code ret;
void *buf;
size_t len, size;
krb5_enctype enctype;
int pa_type;
hx509_cert kdc_cert = NULL;
int 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 (client_params->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 (client_params->dh == NULL) {
ContentInfo info;
type = "enckey";
rep.element = choice_PA_PK_AS_REP_encKeyPack;
ret = krb5_generate_random_keyblock(context, enctype,
&client_params->reply_key);
if (ret) {
free_PA_PK_AS_REP(&rep);
goto out;
}
ret = pk_mk_pa_reply_enckey(context,
config,
client_params,
req,
req_buffer,
&client_params->reply_key,
&info);
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");
} else {
ContentInfo info;
type = "dh";
if (client_params->dh_group_name)
other = client_params->dh_group_name;
rep.element = choice_PA_PK_AS_REP_dhInfo;
ret = generate_dh_keyblock(context, client_params, enctype,
&client_params->reply_key);
if (ret)
return ret;
ret = pk_mk_pa_reply_dh(context, client_params->dh,
client_params,
&client_params->reply_key,
&info,
&kdc_cert);
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");
}
if (ret) {
free_PA_PK_AS_REP(&rep);
goto out;
}
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 (client_params->type == PKINIT_WIN2K) {
PA_PK_AS_REP_Win2k rep;
ContentInfo info;
if (client_params->dh) {
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_encKeyPack;
ret = krb5_generate_random_keyblock(context, enctype,
&client_params->reply_key);
if (ret) {
free_PA_PK_AS_REP_Win2k(&rep);
goto out;
}
ret = pk_mk_pa_reply_enckey(context,
config,
client_params,
req,
req_buffer,
&client_params->reply_key,
&info);
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");
} 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(kdc_identity->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 = &client_params->reply_key;
return ret;
}