summaryrefslogtreecommitdiffstats
path: root/src/libdnssec/keystore/pkcs11.c
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 15:24:08 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 15:24:08 +0000
commitf449f278dd3c70e479a035f50a9bb817a9b433ba (patch)
tree8ca2bfb785dda9bb4d573acdf9b42aea9cd51383 /src/libdnssec/keystore/pkcs11.c
parentInitial commit. (diff)
downloadknot-upstream.tar.xz
knot-upstream.zip
Adding upstream version 3.2.6.upstream/3.2.6upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/libdnssec/keystore/pkcs11.c')
-rw-r--r--src/libdnssec/keystore/pkcs11.c397
1 files changed, 397 insertions, 0 deletions
diff --git a/src/libdnssec/keystore/pkcs11.c b/src/libdnssec/keystore/pkcs11.c
new file mode 100644
index 0000000..2b8b6d5
--- /dev/null
+++ b/src/libdnssec/keystore/pkcs11.c
@@ -0,0 +1,397 @@
+/* Copyright (C) 2022 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz>
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include <gnutls/gnutls.h>
+#include <pthread.h>
+
+#include "contrib/string.h"
+#include "libdnssec/error.h"
+#include "libdnssec/keyid.h"
+#include "libdnssec/shared/keyid_gnutls.h"
+#include "libdnssec/keystore.h"
+#include "libdnssec/keystore/internal.h"
+#include "libdnssec/p11/p11.h"
+#include "libdnssec/pem.h"
+#include "libdnssec/shared/shared.h"
+
+#ifdef ENABLE_PKCS11
+
+struct pkcs11_ctx {
+ char *url;
+};
+
+typedef struct pkcs11_ctx pkcs11_ctx_t;
+
+/*!
+ * Flags used when generating/import key into the token.
+ */
+static const int TOKEN_ADD_FLAGS = GNUTLS_PKCS11_OBJ_FLAG_MARK_SENSITIVE
+ | GNUTLS_PKCS11_OBJ_FLAG_MARK_PRIVATE;
+
+static int key_url(const char *token_uri, const char *key_id, char **url_ptr)
+{
+ assert(token_uri);
+ assert(key_id);
+ assert(url_ptr);
+
+ if (!dnssec_keyid_is_valid(key_id)) {
+ return DNSSEC_INVALID_KEY_ID;
+ }
+
+ size_t token_len = strlen(token_uri);
+ size_t id_len = strlen(key_id);
+
+ // url: <token-url>;id=%aa%bb%cc..
+
+ size_t len = token_len + 4 + (id_len / 2 * 3);
+ char *url = malloc(len + 1);
+ if (!url) {
+ return DNSSEC_ENOMEM;
+ }
+
+ size_t prefix = snprintf(url, len, "%s;id=", token_uri);
+ if (prefix != token_len + 4) {
+ free(url);
+ return DNSSEC_ENOMEM;
+ }
+
+ assert(id_len % 2 == 0);
+ char *pos = url + prefix;
+ for (int i = 0; i < id_len; i += 2, pos += 3) {
+ pos[0] = '%';
+ pos[1] = key_id[i];
+ pos[2] = key_id[i+1];
+ }
+ assert(url + len == pos);
+ url[len] = '\0';
+
+ *url_ptr = url;
+ return DNSSEC_EOK;
+}
+
+/*!
+ * Parse configuration string. Accepted format: "<pkcs11-url> <module-path>"
+ */
+static int parse_config(const char *config, char **uri_ptr, char **module_ptr)
+{
+ const char *space = strchr(config, ' ');
+ if (!space) {
+ return DNSSEC_KEYSTORE_INVALID_CONFIG;
+ }
+
+ char *url = strndup(config, space - config);
+ char *module = strdup(space + 1);
+
+ if (!url || !module) {
+ free(url);
+ free(module);
+ return DNSSEC_ENOMEM;
+ }
+
+ *uri_ptr = url;
+ *module_ptr = module;
+
+ return DNSSEC_EOK;
+}
+
+/*!
+ * Load PKCS #11 module and check if the token is available.
+ */
+static int safe_open(const char *config, char **url_ptr)
+{
+ char *url = NULL;
+ char *module = NULL;
+
+ int r = parse_config(config, &url, &module);
+ if (r != DNSSEC_EOK) {
+ return r;
+ }
+
+ r = p11_load_module(module);
+ free(module);
+ if (r != GNUTLS_E_SUCCESS) {
+ free(url);
+ return DNSSEC_P11_FAILED_TO_LOAD_MODULE;
+ }
+
+ unsigned int flags = 0;
+ r = gnutls_pkcs11_token_get_flags(url, &flags);
+ if (r != GNUTLS_E_SUCCESS) {
+ free(url);
+ return DNSSEC_P11_TOKEN_NOT_AVAILABLE;
+ }
+
+ *url_ptr = url;
+
+ return DNSSEC_EOK;
+}
+
+/* -- internal API --------------------------------------------------------- */
+
+static void disable_pkcs11_callbacks(void)
+{
+ gnutls_pkcs11_set_pin_function(NULL, NULL);
+ gnutls_pkcs11_set_token_function(NULL, NULL);
+}
+
+static int pkcs11_ctx_new(void **ctx_ptr)
+{
+ static pthread_once_t once = PTHREAD_ONCE_INIT;
+ pthread_once(&once, disable_pkcs11_callbacks);
+
+ pkcs11_ctx_t *ctx = calloc(1, sizeof(*ctx));
+ if (!ctx) {
+ return DNSSEC_ENOMEM;
+ }
+
+ *ctx_ptr = ctx;
+
+ return DNSSEC_EOK;
+}
+
+static void pkcs11_ctx_free(void *ctx)
+{
+ free(ctx);
+}
+
+static int pkcs11_init(void *ctx, const char *config)
+{
+ /*
+ * Current keystore initialization is idempotent. We don't really
+ * initialize the token because don't want to wipe the data. We just
+ * check that the token is available the same way pkcs11_open() does.
+ */
+
+ _cleanup_free_ char *url = NULL;
+
+ return safe_open(config, &url);
+}
+
+static int pkcs11_open(void *_ctx, const char *config)
+{
+ pkcs11_ctx_t *ctx = _ctx;
+
+ return safe_open(config, &ctx->url);
+}
+
+static int pkcs11_close(void *_ctx)
+{
+ pkcs11_ctx_t *ctx = _ctx;
+
+ free(ctx->url);
+ clear_struct(ctx);
+
+ return DNSSEC_EOK;
+}
+
+static int pkcs11_generate_key(void *_ctx, gnutls_pk_algorithm_t algorithm,
+ unsigned bits, const char *label, char **id_ptr)
+{
+ pkcs11_ctx_t *ctx = _ctx;
+
+ uint8_t buf[20] = { 0 };
+ gnutls_rnd(GNUTLS_RND_RANDOM, buf, sizeof(buf));
+ dnssec_binary_t cka_id = { .data = buf, .size = sizeof(buf) };
+
+ int flags = TOKEN_ADD_FLAGS | GNUTLS_PKCS11_OBJ_FLAG_LOGIN;
+ gnutls_datum_t gt_cka_id = binary_to_datum(&cka_id);
+ int r = gnutls_pkcs11_privkey_generate3(ctx->url, algorithm, bits, label,
+ &gt_cka_id, 0, NULL, 0, flags);
+ if (r != GNUTLS_E_SUCCESS) {
+ return DNSSEC_KEY_GENERATE_ERROR;
+ }
+
+ char *id = bin_to_hex(cka_id.data, cka_id.size, false);
+ if (id == NULL) {
+ return DNSSEC_ENOMEM;
+ }
+
+ *id_ptr = id;
+
+ return DNSSEC_EOK;
+}
+
+static int import_pem(const dnssec_binary_t *pem,
+ gnutls_x509_privkey_t *key_ptr,
+ gnutls_pubkey_t *pubkey_ptr)
+{
+ gnutls_x509_privkey_t x509_key = NULL;
+ gnutls_privkey_t key = NULL;
+ gnutls_pubkey_t pubkey = NULL;
+
+ int r = dnssec_pem_to_x509(pem, &x509_key);
+ if (r != DNSSEC_EOK) {
+ goto fail;
+ }
+
+ if (gnutls_privkey_init(&key) != GNUTLS_E_SUCCESS ||
+ gnutls_pubkey_init(&pubkey) != GNUTLS_E_SUCCESS
+ ) {
+ r = DNSSEC_ENOMEM;
+ goto fail;
+ }
+
+ if (gnutls_privkey_import_x509(key, x509_key, 0) != GNUTLS_E_SUCCESS ||
+ gnutls_pubkey_import_privkey(pubkey, key, 0, 0) != GNUTLS_E_SUCCESS
+ ) {
+ r = DNSSEC_KEY_IMPORT_ERROR;
+ goto fail;
+ }
+
+fail:
+ gnutls_privkey_deinit(key);
+
+ if (r == DNSSEC_EOK) {
+ *key_ptr = x509_key;
+ *pubkey_ptr = pubkey;
+ } else {
+ gnutls_x509_privkey_deinit(x509_key);
+ gnutls_pubkey_deinit(pubkey);
+ }
+
+ return r;
+}
+
+static int pkcs11_import_key(void *_ctx, const dnssec_binary_t *pem, char **id_ptr)
+{
+ pkcs11_ctx_t *ctx = _ctx;
+
+ _cleanup_x509_privkey_ gnutls_x509_privkey_t key = NULL;
+ _cleanup_pubkey_ gnutls_pubkey_t pubkey = NULL;
+
+ int r = import_pem(pem, &key, &pubkey);
+ if (r != DNSSEC_EOK) {
+ return r;
+ }
+
+ _cleanup_binary_ dnssec_binary_t id = { 0 };
+ r = keyid_x509(key, &id);
+ if (r != DNSSEC_EOK) {
+ return r;
+ }
+
+ int flags = TOKEN_ADD_FLAGS | GNUTLS_PKCS11_OBJ_FLAG_LOGIN;
+ gnutls_datum_t gid = binary_to_datum(&id);
+
+ r = gnutls_pkcs11_copy_x509_privkey2(ctx->url, key, NULL, &gid, 0, flags);
+ if (r != GNUTLS_E_SUCCESS) {
+ return DNSSEC_KEY_IMPORT_ERROR;
+ }
+
+ r = gnutls_pkcs11_copy_pubkey(ctx->url, pubkey, NULL, &gid, 0, flags);
+ if (r != GNUTLS_E_SUCCESS) {
+ // note, we result with dangling private key in the token
+ return DNSSEC_KEY_IMPORT_ERROR;
+ }
+
+ *id_ptr = bin_to_hex(id.data, id.size, false);
+ if (*id_ptr == NULL) {
+ return DNSSEC_ENOMEM;
+ }
+
+ return DNSSEC_EOK;
+}
+
+static int pkcs11_remove_key(void *_ctx, const char *id)
+{
+ pkcs11_ctx_t *ctx = _ctx;
+
+ _cleanup_free_ char *url = NULL;
+ int r = key_url(ctx->url, id, &url);
+ if (r != DNSSEC_EOK) {
+ return r;
+ }
+
+ r = gnutls_pkcs11_delete_url(url, GNUTLS_PKCS11_OBJ_FLAG_LOGIN);
+ if (r < 0) {
+ return DNSSEC_ERROR;
+ } else if (r == 0) {
+ return DNSSEC_ENOENT;
+ }
+
+ return DNSSEC_EOK;
+}
+
+static int pkcs11_get_private(void *_ctx, const char *id, gnutls_privkey_t *key_ptr)
+{
+ pkcs11_ctx_t *ctx = _ctx;
+
+ _cleanup_free_ char *url = NULL;
+ int r = key_url(ctx->url, id, &url);
+ if (r != DNSSEC_EOK) {
+ return r;
+ }
+
+ gnutls_privkey_t key = NULL;
+ r = gnutls_privkey_init(&key);
+ if (r != GNUTLS_E_SUCCESS) {
+ return DNSSEC_ENOMEM;
+ }
+
+ r = gnutls_privkey_import_pkcs11_url(key, url);
+ if (r != GNUTLS_E_SUCCESS) {
+ gnutls_privkey_deinit(key);
+ return DNSSEC_NOT_FOUND;
+ }
+
+ *key_ptr = key;
+
+ return DNSSEC_EOK;
+}
+
+static int pkcs11_set_private(void *ctx, gnutls_privkey_t key)
+{
+ _cleanup_binary_ dnssec_binary_t pem = { 0 };
+ int r = dnssec_pem_from_privkey(key, &pem);
+ if (r != DNSSEC_EOK) {
+ return r;
+ }
+
+ _cleanup_free_ char *keyid = NULL;
+
+ return pkcs11_import_key(ctx, &pem, &keyid);
+}
+
+/* -- public API ----------------------------------------------------------- */
+
+_public_
+int dnssec_keystore_init_pkcs11(dnssec_keystore_t **store_ptr)
+{
+ static const keystore_functions_t IMPLEMENTATION = {
+ .ctx_new = pkcs11_ctx_new,
+ .ctx_free = pkcs11_ctx_free,
+ .init = pkcs11_init,
+ .open = pkcs11_open,
+ .close = pkcs11_close,
+ .generate_key = pkcs11_generate_key,
+ .import_key = pkcs11_import_key,
+ .remove_key = pkcs11_remove_key,
+ .get_private = pkcs11_get_private,
+ .set_private = pkcs11_set_private,
+ };
+
+ return keystore_create(store_ptr, &IMPLEMENTATION);
+}
+
+#else // !ENABLE_PKCS11
+
+_public_
+int dnssec_keystore_init_pkcs11(dnssec_keystore_t **store_ptr)
+{
+ return DNSSEC_NOT_IMPLEMENTED_ERROR;
+}
+
+#endif