/*
* Copyright 2018-2022 The OpenSSL Project Authors. All Rights Reserved.
*
* 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 <openssl/store.h>
#include "internal/cryptlib.h"
#include "crypto/x509.h"
#include "x509_local.h"
/* Generic object loader, given expected type and criterion */
static int cache_objects(X509_LOOKUP *lctx, const char *uri,
const OSSL_STORE_SEARCH *criterion,
int depth, OSSL_LIB_CTX *libctx, const char *propq)
{
int ok = 0;
OSSL_STORE_CTX *ctx = NULL;
X509_STORE *xstore = X509_LOOKUP_get_store(lctx);
if ((ctx = OSSL_STORE_open_ex(uri, libctx, propq, NULL, NULL, NULL,
NULL, NULL)) == NULL)
return 0;
/*
* We try to set the criterion, but don't care if it was valid or not.
* For a OSSL_STORE, it merely serves as an optimization, the expectation
* being that if the criterion couldn't be used, we will get *everything*
* from the container that the URI represents rather than the subset that
* the criterion indicates, so the biggest harm is that we cache more
* objects certs and CRLs than we may expect, but that's ok.
*
* Specifically for OpenSSL's own file: scheme, the only workable
* criterion is the BY_NAME one, which it can only apply on directories,
* but it's possible that the URI is a single file rather than a directory,
* and in that case, the BY_NAME criterion is pointless.
*
* We could very simply not apply any criterion at all here, and just let
* the code that selects certs and CRLs from the cached objects do its job,
* but it's a nice optimization when it can be applied (such as on an
* actual directory with a thousand CA certs).
*/
if (criterion != NULL)
OSSL_STORE_find(ctx, criterion);
for (;;) {
OSSL_STORE_INFO *info = OSSL_STORE_load(ctx);
int infotype;
/* NULL means error or "end of file". Either way, we break. */
if (info == NULL)
break;
infotype = OSSL_STORE_INFO_get_type(info);
ok = 0;
if (infotype == OSSL_STORE_INFO_NAME) {
/*
* This is an entry in the "directory" represented by the current
* uri. if |depth| allows, dive into it.
*/
if (depth > 0)
ok = cache_objects(lctx, OSSL_STORE_INFO_get0_NAME(info),
criterion, depth - 1, libctx, propq);
} else {
/*
* We know that X509_STORE_add_{cert|crl} increments the object's
* refcount, so we can safely use OSSL_STORE_INFO_get0_{cert,crl}
* to get them.
*/
switch (infotype) {
case OSSL_STORE_INFO_CERT:
ok = X509_STORE_add_cert(xstore,
OSSL_STORE_INFO_get0_CERT(info));
break;
case OSSL_STORE_INFO_CRL:
ok = X509_STORE_add_crl(xstore,
OSSL_STORE_INFO_get0_CRL(info));
break;
}
}
OSSL_STORE_INFO_free(info);
if (!ok)
break;
}
OSSL_STORE_close(ctx);
return ok;
}
/* Because OPENSSL_free is a macro and for C type match */
static void free_uri(OPENSSL_STRING data)
{
OPENSSL_free(data);
}
static void by_store_free(X509_LOOKUP *ctx)
{
STACK_OF(OPENSSL_STRING) *uris = X509_LOOKUP_get_method_data(ctx);
sk_OPENSSL_STRING_pop_free(uris, free_uri);
}
static int by_store_ctrl_ex(X509_LOOKUP *ctx, int cmd, const char *argp,
long argl, char **retp, OSSL_LIB_CTX *libctx,
const char *propq)
{
switch (cmd) {
case X509_L_ADD_STORE:
/* If no URI is given, use the default cert dir as default URI */
if (argp == NULL)
argp = ossl_safe_getenv(X509_get_default_cert_dir_env());
if (argp == NULL)
argp = X509_get_default_cert_dir();
{
STACK_OF(OPENSSL_STRING) *uris = X509_LOOKUP_get_method_data(ctx);
char *data = OPENSSL_strdup(argp);
if (data == NULL) {
return 0;
}
if (uris == NULL) {
uris = sk_OPENSSL_STRING_new_null();
X509_LOOKUP_set_method_data(ctx, uris);
}
return sk_OPENSSL_STRING_push(uris, data) > 0;
}
case X509_L_LOAD_STORE:
/* This is a shortcut for quick loading of specific containers */
return cache_objects(ctx, argp, NULL, 0, libctx, propq);
}
return 0;
}
static int by_store_ctrl(X509_LOOKUP *ctx, int cmd,
const char *argp, long argl, char **retp)
{
return by_store_ctrl_ex(ctx, cmd, argp, argl, retp, NULL, NULL);
}
static int by_store(X509_LOOKUP *ctx, X509_LOOKUP_TYPE type,
const OSSL_STORE_SEARCH *criterion, X509_OBJECT *ret,
OSSL_LIB_CTX *libctx, const char *propq)
{
STACK_OF(OPENSSL_STRING) *uris = X509_LOOKUP_get_method_data(ctx);
int i;
int ok = 0;
for (i = 0; i < sk_OPENSSL_STRING_num(uris); i++) {
ok = cache_objects(ctx, sk_OPENSSL_STRING_value(uris, i), criterion,
1 /* depth */, libctx, propq);
if (ok)
break;
}
return ok;
}
static int by_store_subject_ex(X509_LOOKUP *ctx, X509_LOOKUP_TYPE type,
const X509_NAME *name, X509_OBJECT *ret,
OSSL_LIB_CTX *libctx, const char *propq)
{
OSSL_STORE_SEARCH *criterion =
OSSL_STORE_SEARCH_by_name((X509_NAME *)name); /* won't modify it */
int ok = by_store(ctx, type, criterion, ret, libctx, propq);
STACK_OF(X509_OBJECT) *store_objects =
X509_STORE_get0_objects(X509_LOOKUP_get_store(ctx));
X509_OBJECT *tmp = NULL;
OSSL_STORE_SEARCH_free(criterion);
if (ok)
tmp = X509_OBJECT_retrieve_by_subject(store_objects, type, name);
ok = 0;
if (tmp != NULL) {
/*
* This could also be done like this:
*
* if (tmp != NULL) {
* *ret = *tmp;
* ok = 1;
* }
*
* However, we want to exercise the documented API to the max, so
* we do it the hard way.
*
* To be noted is that X509_OBJECT_set1_* increment the refcount,
* but so does X509_STORE_CTX_get_by_subject upon return of this
* function, so we must ensure the refcount is decremented
* before we return, or we will get a refcount leak. We cannot do
* this with X509_OBJECT_free(), though, as that will free a bit
* too much.
*/
switch (type) {
case X509_LU_X509:
ok = X509_OBJECT_set1_X509(ret, tmp->data.x509);
if (ok)
X509_free(tmp->data.x509);
break;
case X509_LU_CRL:
ok = X509_OBJECT_set1_X509_CRL(ret, tmp->data.crl);
if (ok)
X509_CRL_free(tmp->data.crl);
break;
case X509_LU_NONE:
break;
}
}
return ok;
}
static int by_store_subject(X509_LOOKUP *ctx, X509_LOOKUP_TYPE type,
const X509_NAME *name, X509_OBJECT *ret)
{
return by_store_subject_ex(ctx, type, name, ret, NULL, NULL);
}
/*
* We lack the implementations for get_by_issuer_serial, get_by_fingerprint
* and get_by_alias. There's simply not enough support in the X509_LOOKUP
* or X509_STORE APIs.
*/
static X509_LOOKUP_METHOD x509_store_lookup = {
"Load certs from STORE URIs",
NULL, /* new_item */
by_store_free, /* free */
NULL, /* init */
NULL, /* shutdown */
by_store_ctrl, /* ctrl */
by_store_subject, /* get_by_subject */
NULL, /* get_by_issuer_serial */
NULL, /* get_by_fingerprint */
NULL, /* get_by_alias */
by_store_subject_ex,
by_store_ctrl_ex
};
X509_LOOKUP_METHOD *X509_LOOKUP_store(void)
{
return &x509_store_lookup;
}