cmp_genm.c
/*
* Copyright 2022-2023 The OpenSSL Project Authors. All Rights Reserved.
* Copyright Siemens AG 2022
*
* Licensed under the Apache License 2.0 (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*/
#include "cmp_local.h"
#include <openssl/cmp_util.h>
static const X509_VERIFY_PARAM *get0_trustedStore_vpm(const OSSL_CMP_CTX *ctx)
{
const X509_STORE *ts = OSSL_CMP_CTX_get0_trustedStore(ctx);
return ts == NULL ? NULL : X509_STORE_get0_param(ts);
}
static void cert_msg(const char *func, const char *file, int lineno,
OSSL_CMP_severity level, OSSL_CMP_CTX *ctx,
const char *source, X509 *cert, const char *msg)
{
char *subj = X509_NAME_oneline(X509_get_subject_name(cert), NULL, 0);
ossl_cmp_print_log(level, ctx, func, file, lineno,
level == OSSL_CMP_LOG_WARNING ? "WARN" : "ERR",
"certificate from '%s' with subject '%s' %s",
source, subj, msg);
OPENSSL_free(subj);
}
/* use |type_CA| -1 (no CA type check) or 0 (must be EE) or 1 (must be CA) */
static int ossl_X509_check(OSSL_CMP_CTX *ctx, const char *source, X509 *cert,
int type_CA, const X509_VERIFY_PARAM *vpm)
{
uint32_t ex_flags = X509_get_extension_flags(cert);
int res = X509_cmp_timeframe(vpm, X509_get0_notBefore(cert),
X509_get0_notAfter(cert));
int ret = res == 0;
OSSL_CMP_severity level =
vpm == NULL ? OSSL_CMP_LOG_WARNING : OSSL_CMP_LOG_ERR;
if (!ret)
cert_msg(OPENSSL_FUNC, OPENSSL_FILE, OPENSSL_LINE, level, ctx,
source, cert, res > 0 ? "has expired" : "not yet valid");
if (type_CA >= 0 && (ex_flags & EXFLAG_V1) == 0) {
int is_CA = (ex_flags & EXFLAG_CA) != 0;
if ((type_CA != 0) != is_CA) {
cert_msg(OPENSSL_FUNC, OPENSSL_FILE, OPENSSL_LINE, level, ctx,
source, cert,
is_CA ? "is not an EE cert" : "is not a CA cert");
ret = 0;
}
}
return ret;
}
static int ossl_X509_check_all(OSSL_CMP_CTX *ctx, const char *source,
STACK_OF(X509) *certs,
int type_CA, const X509_VERIFY_PARAM *vpm)
{
int i;
int ret = 1;
for (i = 0; i < sk_X509_num(certs /* may be NULL */); i++)
ret = ossl_X509_check(ctx, source,
sk_X509_value(certs, i), type_CA, vpm)
&& ret; /* Having 'ret' after the '&&', all certs are checked. */
return ret;
}
static OSSL_CMP_ITAV *get_genm_itav(OSSL_CMP_CTX *ctx,
OSSL_CMP_ITAV *req, /* gets consumed */
int expected, const char *desc)
{
STACK_OF(OSSL_CMP_ITAV) *itavs = NULL;
int i, n;
if (ctx == NULL) {
ERR_raise(ERR_LIB_CMP, CMP_R_NULL_ARGUMENT);
goto err;
}
if (OSSL_CMP_CTX_get_status(ctx) != OSSL_CMP_PKISTATUS_unspecified) {
ERR_raise_data(ERR_LIB_CMP, CMP_R_UNCLEAN_CTX,
"client context in unsuitable state; should call CMPclient_reinit() before");
goto err;
}
if (!OSSL_CMP_CTX_push0_genm_ITAV(ctx, req))
goto err;
req = NULL;
itavs = OSSL_CMP_exec_GENM_ses(ctx);
if (itavs == NULL) {
if (OSSL_CMP_CTX_get_status(ctx) != OSSL_CMP_PKISTATUS_request)
ERR_raise_data(ERR_LIB_CMP, CMP_R_GETTING_GENP,
"with infoType %s", desc);
return NULL;
}
if ((n = sk_OSSL_CMP_ITAV_num(itavs)) <= 0) {
ERR_raise_data(ERR_LIB_CMP, CMP_R_INVALID_GENP,
"response on genm requesting infoType %s does not include suitable value", desc);
sk_OSSL_CMP_ITAV_free(itavs);
return NULL;
}
if (n > 1)
ossl_cmp_log2(WARN, ctx,
"response on genm contains %d ITAVs; will use the first ITAV with infoType id-it-%s",
n, desc);
for (i = 0; i < n; i++) {
OSSL_CMP_ITAV *itav = sk_OSSL_CMP_ITAV_shift(itavs);
ASN1_OBJECT *obj = OSSL_CMP_ITAV_get0_type(itav);
char name[128] = "genp contains InfoType '";
size_t offset = strlen(name);
if (OBJ_obj2nid(obj) == expected) {
for (i++; i < n; i++)
OSSL_CMP_ITAV_free(sk_OSSL_CMP_ITAV_shift(itavs));
sk_OSSL_CMP_ITAV_free(itavs);
return itav;
}
if (OBJ_obj2txt(name + offset, sizeof(name) - offset, obj, 0) < 0)
strcat(name, "<unknown>");
ossl_cmp_log2(WARN, ctx, "%s' while expecting 'id-it-%s'", name, desc);
OSSL_CMP_ITAV_free(itav);
}
ERR_raise_data(ERR_LIB_CMP, CMP_R_INVALID_GENP,
"could not find any ITAV for %s", desc);
err:
sk_OSSL_CMP_ITAV_free(itavs);
OSSL_CMP_ITAV_free(req);
return NULL;
}
int OSSL_CMP_get1_caCerts(OSSL_CMP_CTX *ctx, STACK_OF(X509) **out)
{
OSSL_CMP_ITAV *req, *itav;
STACK_OF(X509) *certs = NULL;
int ret = 0;
if (out == NULL) {
ERR_raise(ERR_LIB_CMP, CMP_R_NULL_ARGUMENT);
return 0;
}
*out = NULL;
if ((req = OSSL_CMP_ITAV_new_caCerts(NULL)) == NULL)
return 0;
if ((itav = get_genm_itav(ctx, req, NID_id_it_caCerts, "caCerts")) == NULL)
return 0;
if (!OSSL_CMP_ITAV_get0_caCerts(itav, &certs))
goto end;
ret = 1;
if (certs == NULL) /* no CA certificate available */
goto end;
if (!ossl_X509_check_all(ctx, "genp", certs, 1 /* CA */,
get0_trustedStore_vpm(ctx))) {
ret = 0;
goto end;
}
*out = sk_X509_new_reserve(NULL, sk_X509_num(certs));
if (!X509_add_certs(*out, certs,
X509_ADD_FLAG_UP_REF | X509_ADD_FLAG_NO_DUP)) {
sk_X509_pop_free(*out, X509_free);
*out = NULL;
ret = 0;
}
end:
OSSL_CMP_ITAV_free(itav);
return ret;
}
static int selfsigned_verify_cb(int ok, X509_STORE_CTX *store_ctx)
{
if (ok == 0
&& X509_STORE_CTX_get_error_depth(store_ctx) == 0
&& X509_STORE_CTX_get_error(store_ctx)
== X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT) {
/* in this case, custom chain building */
int i;
STACK_OF(X509) *trust;
STACK_OF(X509) *chain = X509_STORE_CTX_get0_chain(store_ctx);
STACK_OF(X509) *untrusted = X509_STORE_CTX_get0_untrusted(store_ctx);
X509_STORE_CTX_check_issued_fn check_issued =
X509_STORE_CTX_get_check_issued(store_ctx);
X509 *cert = sk_X509_value(chain, 0); /* target cert */
X509 *issuer;
for (i = 0; i < sk_X509_num(untrusted); i++) {
cert = sk_X509_value(untrusted, i);
if (!X509_add_cert(chain, cert, X509_ADD_FLAG_UP_REF))
return 0;
}
trust = X509_STORE_get1_all_certs(X509_STORE_CTX_get0_store(store_ctx));
for (i = 0; i < sk_X509_num(trust); i++) {
issuer = sk_X509_value(trust, i);
if ((*check_issued)(store_ctx, cert, issuer)) {
if (X509_add_cert(chain, cert, X509_ADD_FLAG_UP_REF))
ok = 1;
break;
}
}
sk_X509_pop_free(trust, X509_free);
return ok;
} else {
X509_STORE *ts = X509_STORE_CTX_get0_store(store_ctx);
X509_STORE_CTX_verify_cb verify_cb;
if (ts == NULL || (verify_cb = X509_STORE_get_verify_cb(ts)) == NULL)
return ok;
return (*verify_cb)(ok, store_ctx);
}
}
/* vanilla X509_verify_cert() does not support self-signed certs as target */
static int verify_ss_cert(OSSL_LIB_CTX *libctx, const char *propq,
X509_STORE *ts, STACK_OF(X509) *untrusted,
X509 *target)
{
X509_STORE_CTX *csc = NULL;
int ok = 0;
if (ts == NULL || target == NULL) {
ERR_raise(ERR_LIB_CMP, ERR_R_PASSED_NULL_PARAMETER);
return 0;
}
if ((csc = X509_STORE_CTX_new_ex(libctx, propq)) == NULL
|| !X509_STORE_CTX_init(csc, ts, target, untrusted))
goto err;
X509_STORE_CTX_set_verify_cb(csc, selfsigned_verify_cb);
ok = X509_verify_cert(csc) > 0;
err:
X509_STORE_CTX_free(csc);
return ok;
}
static int
verify_ss_cert_trans(OSSL_CMP_CTX *ctx, X509 *trusted /* may be NULL */,
X509 *trans /* the only untrusted cert, may be NULL */,
X509 *target, const char *desc)
{
X509_STORE *ts = OSSL_CMP_CTX_get0_trusted(ctx);
STACK_OF(X509) *untrusted = NULL;
int res = 0;
if (trusted != NULL) {
X509_VERIFY_PARAM *vpm = X509_STORE_get0_param(ts);
if ((ts = X509_STORE_new()) == NULL)
return 0;
if (!X509_STORE_set1_param(ts, vpm)
|| !X509_STORE_add_cert(ts, trusted))
goto err;
}
if (trans != NULL
&& !ossl_x509_add_cert_new(&untrusted, trans, X509_ADD_FLAG_UP_REF))
goto err;
res = verify_ss_cert(OSSL_CMP_CTX_get0_libctx(ctx),
OSSL_CMP_CTX_get0_propq(ctx),
ts, untrusted, target);
if (!res)
ERR_raise_data(ERR_LIB_CMP, CMP_R_INVALID_ROOTCAKEYUPDATE,
"failed to validate %s certificate received in genp %s",
desc, trusted == NULL ? "using trust store"
: "with given certificate as trust anchor");
err:
sk_X509_pop_free(untrusted, X509_free);
if (trusted != NULL)
X509_STORE_free(ts);
return res;
}
int OSSL_CMP_get1_rootCaKeyUpdate(OSSL_CMP_CTX *ctx,
const X509 *oldWithOld, X509 **newWithNew,
X509 **newWithOld, X509 **oldWithNew)
{
X509 *oldWithOld_copy = NULL, *my_newWithOld, *my_oldWithNew;
OSSL_CMP_ITAV *req, *itav;
int res = 0;
if (newWithNew == NULL) {
ERR_raise(ERR_LIB_CMP, ERR_R_PASSED_NULL_PARAMETER);
return 0;
}
*newWithNew = NULL;
if ((req = OSSL_CMP_ITAV_new_rootCaCert(oldWithOld)) == NULL)
return 0;
itav = get_genm_itav(ctx, req, NID_id_it_rootCaKeyUpdate, "rootCaKeyUpdate");
if (itav == NULL)
return 0;
if (!OSSL_CMP_ITAV_get0_rootCaKeyUpdate(itav, newWithNew,
&my_newWithOld, &my_oldWithNew))
goto end;
if (*newWithNew == NULL) /* no root CA cert update available */
goto end;
if ((oldWithOld_copy = X509_dup(oldWithOld)) == NULL && oldWithOld != NULL)
goto end;
if (!verify_ss_cert_trans(ctx, oldWithOld_copy, my_newWithOld,
*newWithNew, "newWithNew")) {
ERR_raise(ERR_LIB_CMP, CMP_R_INVALID_ROOTCAKEYUPDATE);
goto end;
}
if (oldWithOld != NULL && my_oldWithNew != NULL
&& !verify_ss_cert_trans(ctx, *newWithNew, my_oldWithNew,
oldWithOld_copy, "oldWithOld")) {
ERR_raise(ERR_LIB_CMP, CMP_R_INVALID_ROOTCAKEYUPDATE);
goto end;
}
if (!X509_up_ref(*newWithNew))
goto end;
if (newWithOld != NULL &&
(*newWithOld = my_newWithOld) != NULL && !X509_up_ref(*newWithOld))
goto free;
if (oldWithNew == NULL ||
(*oldWithNew = my_oldWithNew) == NULL || X509_up_ref(*oldWithNew)) {
res = 1;
goto end;
}
if (newWithOld != NULL)
X509_free(*newWithOld);
free:
X509_free(*newWithNew);
end:
OSSL_CMP_ITAV_free(itav);
X509_free(oldWithOld_copy);
return res;
}
