Adding upstream version 2.4.38.upstream/2.4.38

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 670 insertions, 0 deletions

diff --git a/modules/md/md_acme_acct.c b/modules/md/md_acme_acct.c
new file mode 100644
index 0000000..c4a2b5f
--- /dev/null
+++ b/modules/md/md_acme_acct.c
@@ -0,0 +1,670 @@
+/* Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+ 
+#include <assert.h>
+#include <stdio.h>
+
+#include <apr_lib.h>
+#include <apr_file_info.h>
+#include <apr_file_io.h>
+#include <apr_fnmatch.h>
+#include <apr_hash.h>
+#include <apr_strings.h>
+#include <apr_tables.h>
+
+#include "md.h"
+#include "md_crypt.h"
+#include "md_json.h"
+#include "md_jws.h"
+#include "md_log.h"
+#include "md_store.h"
+#include "md_util.h"
+#include "md_version.h"
+
+#include "md_acme.h"
+#include "md_acme_acct.h"
+
+static apr_status_t acct_make(md_acme_acct_t **pacct, apr_pool_t *p, 
+                              const char *ca_url, const char *id, apr_array_header_t *contacts)
+{
+    md_acme_acct_t *acct;
+    
+    acct = apr_pcalloc(p, sizeof(*acct));
+
+    acct->id = id? apr_pstrdup(p, id) : NULL;
+    acct->ca_url = ca_url;
+    
+    if (!contacts || apr_is_empty_array(contacts)) {
+        acct->contacts = apr_array_make(p, 5, sizeof(const char *));
+    }
+    else {
+        acct->contacts = apr_array_copy(p, contacts);
+    }
+    
+    *pacct = acct;
+    return APR_SUCCESS;
+}
+
+
+static const char *mk_acct_id(apr_pool_t *p, md_acme_t *acme, int i)
+{
+    return apr_psprintf(p, "ACME-%s-%04d", acme->sname, i);
+}
+
+static const char *mk_acct_pattern(apr_pool_t *p, md_acme_t *acme)
+{
+    return apr_psprintf(p, "ACME-%s-*", acme->sname);
+}
+ 
+/**************************************************************************************************/
+/* json load/save */
+
+static md_json_t *acct_to_json(md_acme_acct_t *acct, apr_pool_t *p)
+{
+    md_json_t *jacct;
+
+    assert(acct);
+    jacct = md_json_create(p);
+    md_json_sets(acct->id, jacct, MD_KEY_ID, NULL);
+    md_json_setb(acct->disabled, jacct, MD_KEY_DISABLED, NULL);
+    md_json_sets(acct->url, jacct, MD_KEY_URL, NULL);
+    md_json_sets(acct->ca_url, jacct, MD_KEY_CA_URL, NULL);
+    md_json_setj(acct->registration, jacct, MD_KEY_REGISTRATION, NULL);
+    if (acct->agreement) {
+        md_json_sets(acct->agreement, jacct, MD_KEY_AGREEMENT, NULL);
+    }
+    
+    return jacct;
+}
+
+static apr_status_t acct_from_json(md_acme_acct_t **pacct, md_json_t *json, apr_pool_t *p)
+{
+    apr_status_t rv = APR_EINVAL;
+    md_acme_acct_t *acct;
+    int disabled;
+    const char *ca_url, *url, *id;
+    apr_array_header_t *contacts;
+    
+    id = md_json_gets(json, MD_KEY_ID, NULL);
+    disabled = md_json_getb(json, MD_KEY_DISABLED, NULL);
+    ca_url = md_json_gets(json, MD_KEY_CA_URL, NULL);
+    if (!ca_url) {
+        md_log_perror(MD_LOG_MARK, MD_LOG_DEBUG, 0, p, "account has no CA url: %s", id);
+        goto out;
+    }
+    
+    url = md_json_gets(json, MD_KEY_URL, NULL);
+    if (!url) {
+        md_log_perror(MD_LOG_MARK, MD_LOG_DEBUG, 0, p, "account has no url: %s", id);
+        goto out;
+    }
+
+    contacts = apr_array_make(p, 5, sizeof(const char *));
+    md_json_getsa(contacts, json, MD_KEY_REGISTRATION, MD_KEY_CONTACT, NULL);
+    rv = acct_make(&acct, p, ca_url, id, contacts);
+    if (APR_SUCCESS == rv) {
+        acct->disabled = disabled;
+        acct->url = url;
+        acct->agreement = md_json_gets(json, "terms-of-service", NULL);
+    }
+
+out:
+    *pacct = (APR_SUCCESS == rv)? acct : NULL;
+    return rv;
+}
+
+apr_status_t md_acme_acct_save_staged(md_acme_t *acme, md_store_t *store, md_t *md, apr_pool_t *p)
+{
+    md_acme_acct_t *acct = acme->acct;
+    md_json_t *jacct;
+    apr_status_t rv;
+    
+    jacct = acct_to_json(acct, p);
+    
+    rv = md_store_save(store, p, MD_SG_STAGING, md->name, MD_FN_ACCOUNT, MD_SV_JSON, jacct, 0);
+    if (APR_SUCCESS == rv) {
+        rv = md_store_save(store, p, MD_SG_STAGING, md->name, MD_FN_ACCT_KEY, 
+                           MD_SV_PKEY, acme->acct_key, 0);
+    }
+    return rv;
+}
+
+apr_status_t md_acme_acct_save(md_store_t *store, apr_pool_t *p, md_acme_t *acme, 
+                               md_acme_acct_t *acct, md_pkey_t *acct_key)
+{
+    md_json_t *jacct;
+    apr_status_t rv;
+    int i;
+    const char *id;
+    
+    jacct = acct_to_json(acct, p);
+    id = acct->id;
+    
+    if (id) {
+        rv = md_store_save(store, p, MD_SG_ACCOUNTS, id, MD_FN_ACCOUNT, MD_SV_JSON, jacct, 0);
+    }
+    else {
+        rv = APR_EAGAIN;
+        for (i = 0; i < 1000 && APR_SUCCESS != rv; ++i) {
+            id = mk_acct_id(p, acme, i);
+            md_json_sets(id, jacct, MD_KEY_ID, NULL);
+            rv = md_store_save(store, p, MD_SG_ACCOUNTS, id, MD_FN_ACCOUNT, MD_SV_JSON, jacct, 1);
+        }
+        
+    }
+    if (APR_SUCCESS == rv) {
+        acct->id = id;
+        rv = md_store_save(store, p, MD_SG_ACCOUNTS, id, MD_FN_ACCT_KEY, MD_SV_PKEY, acct_key, 0);
+    }
+    return rv;
+}
+
+apr_status_t md_acme_save(md_acme_t *acme, md_store_t *store, apr_pool_t *p)
+{
+    return md_acme_acct_save(store, p, acme, acme->acct, acme->acct_key); 
+}
+
+apr_status_t md_acme_acct_load(md_acme_acct_t **pacct, md_pkey_t **ppkey,
+                               md_store_t *store, md_store_group_t group, 
+                               const char *name, apr_pool_t *p)
+{
+    md_json_t *json;
+    apr_status_t rv;
+
+    rv = md_store_load_json(store, group, name, MD_FN_ACCOUNT, &json, p);
+    if (APR_STATUS_IS_ENOENT(rv)) {
+        goto out;
+    }
+    if (APR_SUCCESS != rv) {
+        md_log_perror(MD_LOG_MARK, MD_LOG_DEBUG, rv, p, "error reading account: %s", name);
+        goto out;
+    }
+    
+    rv = acct_from_json(pacct, json, p);
+    if (APR_SUCCESS == rv) {
+        rv = md_store_load(store, group, name, MD_FN_ACCT_KEY, MD_SV_PKEY, (void**)ppkey, p);
+        if (APR_SUCCESS != rv) {
+            md_log_perror(MD_LOG_MARK, MD_LOG_DEBUG, 0, p, "loading key: %s", name);
+            goto out;
+        }
+    }
+out:
+    if (APR_SUCCESS != rv) {
+        *pacct = NULL;
+        *ppkey = NULL;
+    } 
+    return rv;
+}
+
+/**************************************************************************************************/
+/* Lookup */
+
+typedef struct {
+    apr_pool_t *p;
+    md_acme_t *acme;
+    const char *id;
+} find_ctx;
+
+static int find_acct(void *baton, const char *name, const char *aspect,
+                     md_store_vtype_t vtype, void *value, apr_pool_t *ptemp)
+{
+    find_ctx *ctx = baton;
+    int disabled;
+    const char *ca_url, *id;
+    
+    (void)aspect;
+    (void)ptemp;
+    if (MD_SV_JSON == vtype) {
+        md_json_t *json = value;
+        
+        id = md_json_gets(json, MD_KEY_ID, NULL);
+        disabled = md_json_getb(json, MD_KEY_DISABLED, NULL);
+        ca_url = md_json_gets(json, MD_KEY_CA_URL, NULL);
+        
+        if (!disabled && ca_url && !strcmp(ctx->acme->url, ca_url)) {
+            md_log_perror(MD_LOG_MARK, MD_LOG_DEBUG, 0, ctx->p, 
+                          "found account %s for %s: %s, disabled=%d, ca-url=%s", 
+                          name, ctx->acme->url, id, disabled, ca_url);
+            ctx->id = id;
+            return 0;
+        }
+    }
+    return 1;
+}
+
+static apr_status_t acct_find(md_acme_acct_t **pacct, md_pkey_t **ppkey, 
+                              md_store_t *store, md_acme_t *acme, apr_pool_t *p)
+{
+    apr_status_t rv;
+    find_ctx ctx;
+    
+    ctx.p = p;
+    ctx.acme = acme;
+    ctx.id = NULL;
+    
+    rv = md_store_iter(find_acct, &ctx, store, p, MD_SG_ACCOUNTS, mk_acct_pattern(p, acme),
+                       MD_FN_ACCOUNT, MD_SV_JSON);
+    if (ctx.id) {
+        rv = md_acme_acct_load(pacct, ppkey, store, MD_SG_ACCOUNTS, ctx.id, p);
+    }
+    else {
+        *pacct = NULL;
+        rv = APR_ENOENT;
+    }
+    md_log_perror(MD_LOG_MARK, MD_LOG_DEBUG, rv, p, 
+                  "acct_find %s", (*pacct)? (*pacct)->id : "NULL"); 
+    return rv;
+}
+
+/**************************************************************************************************/
+/* Register a new account */
+
+typedef struct {
+    md_acme_t *acme;
+    apr_pool_t *p;
+} acct_ctx_t;
+
+static apr_status_t on_init_acct_new(md_acme_req_t *req, void *baton)
+{
+    acct_ctx_t *ctx = baton;
+    md_json_t *jpayload;
+
+    jpayload = md_json_create(req->p);
+    md_json_sets("new-reg", jpayload, MD_KEY_RESOURCE, NULL);
+    md_json_setsa(ctx->acme->acct->contacts, jpayload, MD_KEY_CONTACT, NULL);
+    if (ctx->acme->acct->agreement) {
+        md_json_sets(ctx->acme->acct->agreement, jpayload, MD_KEY_AGREEMENT, NULL);
+    }
+    
+    return md_acme_req_body_init(req, jpayload);
+} 
+
+static apr_status_t acct_upd(md_acme_t *acme, apr_pool_t *p, 
+                             const apr_table_t *hdrs, md_json_t *body, void *baton)
+{
+    acct_ctx_t *ctx = baton;
+    apr_status_t rv = APR_SUCCESS;
+    md_acme_acct_t *acct = acme->acct;
+    
+    if (!acct->url) {
+        const char *location = apr_table_get(hdrs, "location");
+        if (!location) {
+            md_log_perror(MD_LOG_MARK, MD_LOG_WARNING, APR_EINVAL, p, "new acct without location");
+            return APR_EINVAL;
+        }
+        acct->url = apr_pstrdup(ctx->p, location);
+    }
+    if (!acct->tos_required) {
+        acct->tos_required = md_link_find_relation(hdrs, ctx->p, "terms-of-service");
+        if (acct->tos_required) {
+            md_log_perror(MD_LOG_MARK, MD_LOG_DEBUG, 0, p, 
+                          "server requires agreement to <%s>", acct->tos_required);
+        }
+    }
+    
+    apr_array_clear(acct->contacts);
+    md_json_getsa(acct->contacts, body, MD_KEY_CONTACT, NULL);
+    acct->registration = md_json_clone(ctx->p, body);
+    
+    md_log_perror(MD_LOG_MARK, MD_LOG_DEBUG, rv, p, "updated acct %s", acct->url);
+    return rv;
+}
+
+static apr_status_t acct_register(md_acme_t *acme, apr_pool_t *p,  
+                                  apr_array_header_t *contacts, const char *agreement)
+{
+    apr_status_t rv;
+    md_pkey_t *pkey;
+    const char *err = NULL, *uri;
+    md_pkey_spec_t spec;
+    int i;
+    
+    md_log_perror(MD_LOG_MARK, MD_LOG_DEBUG, 0, p, "create new account");
+    
+    if (agreement) {
+        if (APR_SUCCESS != (rv = md_util_abs_uri_check(acme->p, agreement, &err))) {
+            md_log_perror(MD_LOG_MARK, MD_LOG_ERR, 0, p, 
+                          "invalid agreement uri (%s): %s", err, agreement);
+            goto out;
+        }
+    }
+    for (i = 0; i < contacts->nelts; ++i) {
+        uri = APR_ARRAY_IDX(contacts, i, const char *);
+        if (APR_SUCCESS != (rv = md_util_abs_uri_check(acme->p, uri, &err))) {
+            md_log_perror(MD_LOG_MARK, MD_LOG_ERR, 0, p, 
+                          "invalid contact uri (%s): %s", err, uri);
+            goto out;
+        }
+    }
+    
+    spec.type = MD_PKEY_TYPE_RSA;
+    spec.params.rsa.bits = MD_ACME_ACCT_PKEY_BITS;
+    
+    if (APR_SUCCESS == (rv = md_pkey_gen(&pkey, acme->p, &spec))
+        && APR_SUCCESS == (rv = acct_make(&acme->acct,  p, acme->url, NULL, contacts))) {
+        acct_ctx_t ctx;
+
+        acme->acct_key = pkey;
+        if (agreement) {
+            acme->acct->agreement = agreement;
+        }
+
+        ctx.acme = acme;
+        ctx.p = p;
+        rv = md_acme_POST(acme, acme->new_reg, on_init_acct_new, acct_upd, NULL, &ctx);
+        if (APR_SUCCESS == rv) {
+            md_log_perror(MD_LOG_MARK, MD_LOG_INFO, 0, p, 
+                          "registered new account %s", acme->acct->url);
+        }
+    }
+
+out:    
+    if (APR_SUCCESS != rv && acme->acct) {
+        acme->acct = NULL;
+    }
+    return rv;
+}
+
+/**************************************************************************************************/
+/* acct validation */
+
+static apr_status_t on_init_acct_valid(md_acme_req_t *req, void *baton)
+{
+    md_json_t *jpayload;
+
+    (void)baton;
+    jpayload = md_json_create(req->p);
+    md_json_sets("reg", jpayload, MD_KEY_RESOURCE, NULL);
+    
+    return md_acme_req_body_init(req, jpayload);
+} 
+
+static apr_status_t acct_valid(md_acme_t *acme, apr_pool_t *p, const apr_table_t *hdrs, 
+                               md_json_t *body, void *baton)
+{
+    md_acme_acct_t *acct = acme->acct;
+    apr_status_t rv = APR_SUCCESS;
+    const char *body_str;
+    const char *tos_required;
+    
+    (void)p;
+    (void)baton;
+    apr_array_clear(acct->contacts);
+    md_json_getsa(acct->contacts, body, MD_KEY_CONTACT, NULL);
+    acct->registration = md_json_clone(acme->p, body);
+    
+    body_str = md_json_writep(body, acme->p, MD_JSON_FMT_INDENT);
+    md_log_perror(MD_LOG_MARK, MD_LOG_DEBUG, rv, acme->p, "validate acct %s: %s", 
+                  acct->url, body_str ? body_str : "<failed to serialize!>");
+    
+    acct->agreement = md_json_gets(acct->registration, MD_KEY_AGREEMENT, NULL);
+    tos_required = md_link_find_relation(hdrs, acme->p, "terms-of-service");
+    
+    if (tos_required) {
+        if (!acct->agreement || strcmp(tos_required, acct->agreement)) {
+            md_log_perror(MD_LOG_MARK, MD_LOG_DEBUG, rv, acme->p, 
+                          "needs to agree to terms-of-service '%s', "
+                          "has already agreed to '%s'", 
+                          tos_required, acct->agreement);
+        }
+        acct->tos_required = tos_required;
+    }
+    
+    return rv;
+}
+
+static apr_status_t md_acme_validate_acct(md_acme_t *acme)
+{
+    md_log_perror(MD_LOG_MARK, MD_LOG_DEBUG, 0, acme->p, "acct validation");
+    if (!acme->acct) {
+        return APR_EINVAL;
+    }
+    return md_acme_POST(acme, acme->acct->url, on_init_acct_valid, acct_valid, NULL, NULL);
+}
+
+/**************************************************************************************************/
+/* account setup */
+
+static apr_status_t acct_validate(md_acme_t *acme, md_store_t *store, apr_pool_t *p)
+{
+    apr_status_t rv;
+    
+    if (APR_SUCCESS != (rv = md_acme_validate_acct(acme))) {
+        if (acme->acct && (APR_ENOENT == rv || APR_EACCES == rv)) {
+            if (!acme->acct->disabled) {
+                acme->acct->disabled = 1;
+                if (store) {
+                    md_acme_save(acme, store, p);
+                }
+            }
+            acme->acct = NULL;
+            acme->acct_key = NULL;
+            rv = APR_ENOENT;
+        }
+    }
+    return rv;
+}
+
+apr_status_t md_acme_use_acct(md_acme_t *acme, md_store_t *store,
+                              apr_pool_t *p, const char *acct_id)
+{
+    md_acme_acct_t *acct;
+    md_pkey_t *pkey;
+    apr_status_t rv;
+    
+    if (APR_SUCCESS == (rv = md_acme_acct_load(&acct, &pkey, 
+                                               store, MD_SG_ACCOUNTS, acct_id, acme->p))) {
+        if (acct->ca_url && !strcmp(acct->ca_url, acme->url)) {
+            acme->acct = acct;
+            acme->acct_key = pkey;
+            rv = acct_validate(acme, store, p);
+        }
+        else {
+            /* account is from a nother server or, more likely, from another
+             * protocol endpoint on the same server */
+            rv = APR_ENOENT;
+        }
+    }
+    return rv;
+}
+
+apr_status_t md_acme_use_acct_staged(md_acme_t *acme, struct md_store_t *store, 
+                                     md_t *md, apr_pool_t *p)
+{
+    md_acme_acct_t *acct;
+    md_pkey_t *pkey;
+    apr_status_t rv;
+    
+    if (APR_SUCCESS == (rv = md_acme_acct_load(&acct, &pkey, 
+                                               store, MD_SG_STAGING, md->name, acme->p))) {
+        acme->acct = acct;
+        acme->acct_key = pkey;
+        rv = acct_validate(acme, NULL, p);
+    }
+    return rv;
+}
+
+const char *md_acme_get_acct_id(md_acme_t *acme)
+{
+    return acme->acct? acme->acct->id : NULL;
+}
+
+const char *md_acme_get_agreement(md_acme_t *acme)
+{
+    return acme->acct? acme->acct->agreement : NULL;
+}
+
+apr_status_t md_acme_find_acct(md_acme_t *acme, md_store_t *store, apr_pool_t *p)
+{
+    md_acme_acct_t *acct;
+    md_pkey_t *pkey;
+    apr_status_t rv;
+    
+    while (APR_SUCCESS == acct_find(&acct, &pkey, store, acme, acme->p)) {
+        acme->acct = acct;
+        acme->acct_key = pkey;
+        rv = acct_validate(acme, store, p);
+        
+        if (APR_SUCCESS == rv) {
+            return rv;
+        }
+        else {
+            acme->acct = NULL;
+            acme->acct_key = NULL;
+            if (!APR_STATUS_IS_ENOENT(rv)) {
+                /* encountered error with server */
+                return rv;
+            }
+        }
+    }
+    return APR_ENOENT;
+}
+
+apr_status_t md_acme_create_acct(md_acme_t *acme, apr_pool_t *p, apr_array_header_t *contacts, 
+                                 const char *agreement)
+{
+    return acct_register(acme, p, contacts, agreement);
+}
+
+/**************************************************************************************************/
+/* Delete the account */
+
+apr_status_t md_acme_unstore_acct(md_store_t *store, apr_pool_t *p, const char *acct_id) 
+{
+    apr_status_t rv = APR_SUCCESS;
+    
+    rv = md_store_remove(store, MD_SG_ACCOUNTS, acct_id, MD_FN_ACCOUNT, p, 1);
+    if (APR_SUCCESS == rv) {
+        md_store_remove(store, MD_SG_ACCOUNTS, acct_id, MD_FN_ACCT_KEY, p, 1);
+    }
+    return rv;
+}
+
+static apr_status_t on_init_acct_del(md_acme_req_t *req, void *baton)
+{
+    md_json_t *jpayload;
+
+    (void)baton;
+    jpayload = md_json_create(req->p);
+    md_json_sets("reg", jpayload, MD_KEY_RESOURCE, NULL);
+    md_json_setb(1, jpayload, "delete", NULL);
+    
+    return md_acme_req_body_init(req, jpayload);
+} 
+
+static apr_status_t acct_del(md_acme_t *acme, apr_pool_t *p,
+                             const apr_table_t *hdrs, md_json_t *body, void *baton)
+{
+    md_store_t *store = baton;
+    apr_status_t rv = APR_SUCCESS;
+
+    (void)hdrs;
+    (void)body;
+    md_log_perror(MD_LOG_MARK, MD_LOG_INFO, 0, p, "deleted account %s", acme->acct->url);
+    if (store) {
+        rv = md_acme_unstore_acct(store, p, acme->acct->id);
+        acme->acct = NULL;
+        acme->acct_key = NULL;
+    }
+    return rv;
+}
+
+apr_status_t md_acme_delete_acct(md_acme_t *acme, md_store_t *store, apr_pool_t *p)
+{
+    md_acme_acct_t *acct = acme->acct;
+    
+    (void)p;
+    if (!acct) {
+        return APR_EINVAL;
+    }
+    md_log_perror(MD_LOG_MARK, MD_LOG_DEBUG, 0, acme->p, "delete account %s from %s", 
+                  acct->url, acct->ca_url);
+    return md_acme_POST(acme, acct->url, on_init_acct_del, acct_del, NULL, store);
+}
+
+/**************************************************************************************************/
+/* terms-of-service */
+
+static apr_status_t on_init_agree_tos(md_acme_req_t *req, void *baton)
+{
+    acct_ctx_t *ctx = baton;
+    md_json_t *jpayload;
+
+    jpayload = md_json_create(req->p);
+    md_json_sets("reg", jpayload, MD_KEY_RESOURCE, NULL);
+    md_json_sets(ctx->acme->acct->agreement, jpayload, MD_KEY_AGREEMENT, NULL);
+    
+    return md_acme_req_body_init(req, jpayload);
+} 
+
+apr_status_t md_acme_agree(md_acme_t *acme, apr_pool_t *p, const char *agreement)
+{
+    acct_ctx_t ctx;
+    
+    acme->acct->agreement = agreement;
+    ctx.acme = acme;
+    ctx.p = p;
+    return md_acme_POST(acme, acme->acct->url, on_init_agree_tos, acct_upd, NULL, &ctx);
+}
+
+static int agreement_required(md_acme_acct_t *acct)
+{
+    /* We used to really check if the account agreement and the one
+     * indicated as valid are the very same:
+     * return (!acct->agreement 
+     *       || (acct->tos_required && strcmp(acct->tos_required, acct->agreement)));
+     * However, LE is happy if the account has agreed to a ToS in the past and
+     * does not required a renewed acceptance.
+     */
+     return !acct->agreement; 
+}
+
+apr_status_t md_acme_check_agreement(md_acme_t *acme, apr_pool_t *p, 
+                                     const char *agreement, const char **prequired)
+{
+    apr_status_t rv = APR_SUCCESS;
+    
+    /* Check if (correct) Terms-of-Service for account were accepted */
+    *prequired = NULL;
+    if (agreement_required(acme->acct)) {
+        const char *tos = acme->acct->tos_required;
+        if (!tos) {
+            if (APR_SUCCESS != (rv = md_acme_validate_acct(acme))) {
+                md_log_perror(MD_LOG_MARK, MD_LOG_DEBUG, rv, acme->p, 
+                              "validate for account %s", acme->acct->id); 
+                return rv;
+            }
+            tos = acme->acct->tos_required; 
+            if (!tos) {
+                md_log_perror(MD_LOG_MARK, MD_LOG_DEBUG, rv, acme->p, "unknown terms-of-service "
+                              "required after validation of account %s", acme->acct->id); 
+                return APR_EGENERAL;
+            }
+        }
+        
+        if (acme->acct->agreement && !strcmp(tos, acme->acct->agreement)) {
+            rv = md_acme_agree(acme, p, tos);
+        }
+        else if (agreement && !strcmp(tos, agreement)) {
+            rv = md_acme_agree(acme, p, tos);
+        }
+        else {
+            *prequired = apr_pstrdup(p, tos);
+            rv = APR_INCOMPLETE;
+        }
+    }
+    return rv;
+}