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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-10 20:49:52 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-10 20:49:52 +0000
commit55944e5e40b1be2afc4855d8d2baf4b73d1876b5 (patch)
tree33f869f55a1b149e9b7c2b7e201867ca5dd52992 /src/boot/efi/device-path-util.c
parentInitial commit. (diff)
downloadsystemd-55944e5e40b1be2afc4855d8d2baf4b73d1876b5.tar.xz
systemd-55944e5e40b1be2afc4855d8d2baf4b73d1876b5.zip
Adding upstream version 255.4.upstream/255.4
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/boot/efi/device-path-util.c')
-rw-r--r--src/boot/efi/device-path-util.c138
1 files changed, 138 insertions, 0 deletions
diff --git a/src/boot/efi/device-path-util.c b/src/boot/efi/device-path-util.c
new file mode 100644
index 0000000..2a85e8b
--- /dev/null
+++ b/src/boot/efi/device-path-util.c
@@ -0,0 +1,138 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include "device-path-util.h"
+#include "util.h"
+
+EFI_STATUS make_file_device_path(EFI_HANDLE device, const char16_t *file, EFI_DEVICE_PATH **ret_dp) {
+ EFI_STATUS err;
+ EFI_DEVICE_PATH *dp;
+
+ assert(file);
+ assert(ret_dp);
+
+ err = BS->HandleProtocol(device, MAKE_GUID_PTR(EFI_DEVICE_PATH_PROTOCOL), (void **) &dp);
+ if (err != EFI_SUCCESS)
+ return err;
+
+ EFI_DEVICE_PATH *end_node = dp;
+ while (!device_path_is_end(end_node))
+ end_node = device_path_next_node(end_node);
+
+ size_t file_size = strsize16(file);
+ size_t dp_size = (uint8_t *) end_node - (uint8_t *) dp;
+
+ /* Make a copy that can also hold a file media device path. */
+ *ret_dp = xmalloc(dp_size + file_size + sizeof(FILEPATH_DEVICE_PATH) + sizeof(EFI_DEVICE_PATH));
+ dp = mempcpy(*ret_dp, dp, dp_size);
+
+ FILEPATH_DEVICE_PATH *file_dp = (FILEPATH_DEVICE_PATH *) dp;
+ file_dp->Header = (EFI_DEVICE_PATH) {
+ .Type = MEDIA_DEVICE_PATH,
+ .SubType = MEDIA_FILEPATH_DP,
+ .Length = sizeof(FILEPATH_DEVICE_PATH) + file_size,
+ };
+ memcpy(file_dp->PathName, file, file_size);
+
+ dp = device_path_next_node(dp);
+ *dp = DEVICE_PATH_END_NODE;
+ return EFI_SUCCESS;
+}
+
+static char16_t *device_path_to_str_internal(const EFI_DEVICE_PATH *dp) {
+ char16_t *str = NULL;
+
+ for (const EFI_DEVICE_PATH *node = dp; !device_path_is_end(node); node = device_path_next_node(node)) {
+ _cleanup_free_ char16_t *old = str;
+
+ if (node->Type == END_DEVICE_PATH_TYPE && node->SubType == END_INSTANCE_DEVICE_PATH_SUBTYPE) {
+ str = xasprintf("%ls%s,", strempty(old), old ? "\\" : "");
+ continue;
+ }
+
+ /* Special-case this so that FilePath-only device path string look and behave nicely. */
+ if (node->Type == MEDIA_DEVICE_PATH && node->SubType == MEDIA_FILEPATH_DP) {
+ str = xasprintf("%ls%s%ls",
+ strempty(old),
+ old ? "\\" : "",
+ ((FILEPATH_DEVICE_PATH *) node)->PathName);
+ continue;
+ }
+
+ /* Instead of coding all the different types and sub-types here we just use the
+ * generic node form. This function is a best-effort for firmware that does not
+ * provide the EFI_DEVICE_PATH_TO_TEXT_PROTOCOL after all. */
+
+ size_t size = node->Length - sizeof(EFI_DEVICE_PATH);
+ _cleanup_free_ char16_t *hex_data = hexdump((uint8_t *) node + sizeof(EFI_DEVICE_PATH), size);
+ str = xasprintf("%ls%sPath(%u,%u%s%ls)",
+ strempty(old),
+ old ? "/" : "",
+ node->Type,
+ node->SubType,
+ size == 0 ? "" : ",",
+ hex_data);
+ }
+
+ return str;
+}
+
+EFI_STATUS device_path_to_str(const EFI_DEVICE_PATH *dp, char16_t **ret) {
+ EFI_DEVICE_PATH_TO_TEXT_PROTOCOL *dp_to_text;
+ EFI_STATUS err;
+ _cleanup_free_ char16_t *str = NULL;
+
+ assert(dp);
+ assert(ret);
+
+ err = BS->LocateProtocol(MAKE_GUID_PTR(EFI_DEVICE_PATH_TO_TEXT_PROTOCOL), NULL, (void **) &dp_to_text);
+ if (err != EFI_SUCCESS) {
+ *ret = device_path_to_str_internal(dp);
+ return EFI_SUCCESS;
+ }
+
+ str = dp_to_text->ConvertDevicePathToText(dp, false, false);
+ if (!str)
+ return EFI_OUT_OF_RESOURCES;
+
+ *ret = TAKE_PTR(str);
+ return EFI_SUCCESS;
+}
+
+bool device_path_startswith(const EFI_DEVICE_PATH *dp, const EFI_DEVICE_PATH *start) {
+ if (!start)
+ return true;
+ if (!dp)
+ return false;
+ for (;;) {
+ if (device_path_is_end(start))
+ return true;
+ if (device_path_is_end(dp))
+ return false;
+ if (start->Length != dp->Length)
+ return false;
+ if (memcmp(dp, start, start->Length) != 0)
+ return false;
+ start = device_path_next_node(start);
+ dp = device_path_next_node(dp);
+ }
+}
+
+EFI_DEVICE_PATH *device_path_replace_node(
+ const EFI_DEVICE_PATH *path, const EFI_DEVICE_PATH *node, const EFI_DEVICE_PATH *new_node) {
+
+ /* Create a new device path as a copy of path, while chopping off the remainder starting at the given
+ * node. If new_node is provided, it is appended at the end of the new path. */
+
+ assert(path);
+ assert(node);
+
+ size_t len = (uint8_t *) node - (uint8_t *) path;
+ EFI_DEVICE_PATH *ret = xmalloc(len + (new_node ? new_node->Length : 0) + sizeof(EFI_DEVICE_PATH));
+ EFI_DEVICE_PATH *end = mempcpy(ret, path, len);
+
+ if (new_node)
+ end = mempcpy(end, new_node, new_node->Length);
+
+ *end = DEVICE_PATH_END_NODE;
+ return ret;
+}