Adding upstream version 255.4.upstream/255.4

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

1 files changed, 173 insertions, 0 deletions

diff --git a/src/cryptsetup/cryptsetup-pkcs11.c b/src/cryptsetup/cryptsetup-pkcs11.c
new file mode 100644
index 0000000..f991389
--- /dev/null
+++ b/src/cryptsetup/cryptsetup-pkcs11.c
@@ -0,0 +1,173 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include <fcntl.h>
+#include <unistd.h>
+#include <sys/stat.h>
+
+#include <p11-kit/p11-kit.h>
+#include <p11-kit/uri.h>
+
+#include "alloc-util.h"
+#include "ask-password-api.h"
+#include "cryptsetup-pkcs11.h"
+#include "escape.h"
+#include "fd-util.h"
+#include "fileio.h"
+#include "format-util.h"
+#include "hexdecoct.h"
+#include "json.h"
+#include "macro.h"
+#include "memory-util.h"
+#include "parse-util.h"
+#include "pkcs11-util.h"
+#include "random-util.h"
+#include "stat-util.h"
+#include "strv.h"
+
+int decrypt_pkcs11_key(
+                const char *volume_name,
+                const char *friendly_name,
+                const char *pkcs11_uri,
+                const char *key_file,         /* We either expect key_file and associated parameters to be set (for file keys) … */
+                size_t key_file_size,
+                uint64_t key_file_offset,
+                const void *key_data,         /* … or key_data and key_data_size (for literal keys) */
+                size_t key_data_size,
+                usec_t until,
+                bool headless,
+                void **ret_decrypted_key,
+                size_t *ret_decrypted_key_size) {
+
+        _cleanup_(pkcs11_crypt_device_callback_data_release) pkcs11_crypt_device_callback_data data = {
+                .friendly_name = friendly_name,
+                .until = until,
+                .headless = headless,
+        };
+        int r;
+
+        assert(friendly_name);
+        assert(pkcs11_uri);
+        assert(key_file || key_data);
+        assert(ret_decrypted_key);
+        assert(ret_decrypted_key_size);
+
+        /* The functions called here log about all errors, except for EAGAIN which means "token not found right now" */
+
+        if (key_data) {
+                data.encrypted_key = (void*) key_data;
+                data.encrypted_key_size = key_data_size;
+
+                data.free_encrypted_key = false;
+        } else {
+                _cleanup_free_ char *bindname = NULL;
+
+                /* If we read the key via AF_UNIX, make this client recognizable */
+                if (asprintf(&bindname, "@%" PRIx64"/cryptsetup-pkcs11/%s", random_u64(), volume_name) < 0)
+                        return log_oom();
+
+                r = read_full_file_full(
+                                AT_FDCWD, key_file,
+                                key_file_offset == 0 ? UINT64_MAX : key_file_offset,
+                                key_file_size == 0 ? SIZE_MAX : key_file_size,
+                                READ_FULL_FILE_CONNECT_SOCKET,
+                                bindname,
+                                (char**) &data.encrypted_key, &data.encrypted_key_size);
+                if (r < 0)
+                        return r;
+
+                data.free_encrypted_key = true;
+        }
+
+        r = pkcs11_find_token(pkcs11_uri, pkcs11_crypt_device_callback, &data);
+        if (r < 0)
+                return r;
+
+        *ret_decrypted_key = TAKE_PTR(data.decrypted_key);
+        *ret_decrypted_key_size = data.decrypted_key_size;
+
+        return 0;
+}
+
+int find_pkcs11_auto_data(
+                struct crypt_device *cd,
+                char **ret_uri,
+                void **ret_encrypted_key,
+                size_t *ret_encrypted_key_size,
+                int *ret_keyslot) {
+
+        _cleanup_free_ char *uri = NULL;
+        _cleanup_free_ void *key = NULL;
+        int r, keyslot = -1;
+        size_t key_size = 0;
+
+        assert(cd);
+        assert(ret_uri);
+        assert(ret_encrypted_key);
+        assert(ret_encrypted_key_size);
+        assert(ret_keyslot);
+
+        /* Loads PKCS#11 metadata from LUKS2 JSON token headers. */
+
+        for (int token = 0; token < sym_crypt_token_max(CRYPT_LUKS2); token++) {
+                _cleanup_(json_variant_unrefp) JsonVariant *v = NULL;
+                JsonVariant *w;
+                int ks;
+
+                r = cryptsetup_get_token_as_json(cd, token, "systemd-pkcs11", &v);
+                if (IN_SET(r, -ENOENT, -EINVAL, -EMEDIUMTYPE))
+                        continue;
+                if (r < 0)
+                        return log_error_errno(r, "Failed to read JSON token data off disk: %m");
+
+                ks = cryptsetup_get_keyslot_from_token(v);
+                if (ks < 0) {
+                        /* Handle parsing errors of the keyslots field gracefully, since it's not 'owned' by
+                         * us, but by the LUKS2 spec */
+                        log_warning_errno(ks, "Failed to extract keyslot index from PKCS#11 JSON data token %i, skipping: %m", token);
+                        continue;
+                }
+
+                if (uri)
+                        return log_error_errno(SYNTHETIC_ERRNO(ENOTUNIQ),
+                                               "Multiple PKCS#11 tokens enrolled, cannot automatically determine token.");
+
+                assert(keyslot < 0);
+                keyslot = ks;
+
+                w = json_variant_by_key(v, "pkcs11-uri");
+                if (!w || !json_variant_is_string(w))
+                        return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+                                               "PKCS#11 token data lacks 'pkcs11-uri' field.");
+
+                uri = strdup(json_variant_string(w));
+                if (!uri)
+                        return log_oom();
+
+                if (!pkcs11_uri_valid(uri))
+                        return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+                                               "PKCS#11 token data contains invalid PKCS#11 URI.");
+
+                w = json_variant_by_key(v, "pkcs11-key");
+                if (!w || !json_variant_is_string(w))
+                        return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+                                               "PKCS#11 token data lacks 'pkcs11-key' field.");
+
+                assert(!key);
+                assert(key_size == 0);
+                r = unbase64mem(json_variant_string(w), SIZE_MAX, &key, &key_size);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to decode base64 encoded key.");
+        }
+
+        if (!uri)
+                return log_error_errno(SYNTHETIC_ERRNO(ENXIO),
+                                       "No valid PKCS#11 token data found.");
+
+        log_info("Automatically discovered security PKCS#11 token '%s' unlocks volume.", uri);
+
+        *ret_uri = TAKE_PTR(uri);
+        *ret_encrypted_key = TAKE_PTR(key);
+        *ret_encrypted_key_size = key_size;
+        *ret_keyslot = keyslot;
+        return 0;
+}