summaryrefslogtreecommitdiffstats
path: root/src/udev/fido_id/fido_id.c
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--src/udev/fido_id/fido_id.c95
1 files changed, 95 insertions, 0 deletions
diff --git a/src/udev/fido_id/fido_id.c b/src/udev/fido_id/fido_id.c
new file mode 100644
index 0000000..58a2827
--- /dev/null
+++ b/src/udev/fido_id/fido_id.c
@@ -0,0 +1,95 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Identifies FIDO CTAP1 ("U2F")/CTAP2 security tokens based on the usage declared in their report
+ * descriptor and outputs suitable environment variables.
+ *
+ * Inspired by Andrew Lutomirski's 'u2f-hidraw-policy.c'
+ */
+
+#include <errno.h>
+#include <fcntl.h>
+#include <linux/hid.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include "device-private.h"
+#include "device-util.h"
+#include "fd-util.h"
+#include "fido_id_desc.h"
+#include "log.h"
+#include "macro.h"
+#include "main-func.h"
+#include "path-util.h"
+#include "string-util.h"
+#include "udev-util.h"
+
+static int run(int argc, char **argv) {
+ _cleanup_(sd_device_unrefp) struct sd_device *device = NULL;
+ _cleanup_free_ char *desc_path = NULL;
+ _cleanup_close_ int fd = -1;
+
+ struct sd_device *hid_device;
+ const char *sys_path;
+ uint8_t desc[HID_MAX_DESCRIPTOR_SIZE];
+ ssize_t desc_len;
+
+ int r;
+
+ log_set_target(LOG_TARGET_AUTO);
+ udev_parse_config();
+ log_parse_environment();
+ log_open();
+
+ if (argc > 2)
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Usage: %s [SYSFS_PATH]", program_invocation_short_name);
+
+ if (argc == 1) {
+ r = device_new_from_strv(&device, environ);
+ if (r < 0)
+ return log_error_errno(r, "Failed to get current device from environment: %m");
+ } else {
+ r = sd_device_new_from_syspath(&device, argv[1]);
+ if (r < 0)
+ return log_error_errno(r, "Failed to get device from syspath: %m");
+ }
+
+ r = sd_device_get_parent(device, &hid_device);
+ if (r < 0)
+ return log_device_error_errno(device, r, "Failed to get parent HID device: %m");
+
+ r = sd_device_get_syspath(hid_device, &sys_path);
+ if (r < 0)
+ return log_device_error_errno(hid_device, r, "Failed to get syspath for HID device: %m");
+
+ desc_path = path_join(sys_path, "report_descriptor");
+ if (!desc_path)
+ return log_oom();
+
+ fd = open(desc_path, O_RDONLY | O_NOFOLLOW | O_CLOEXEC | O_NOCTTY);
+ if (fd < 0)
+ return log_device_error_errno(hid_device, errno,
+ "Failed to open report descriptor at '%s': %m", desc_path);
+
+ desc_len = read(fd, desc, sizeof(desc));
+ if (desc_len < 0)
+ return log_device_error_errno(hid_device, errno,
+ "Failed to read report descriptor at '%s': %m", desc_path);
+ if (desc_len == 0)
+ return log_device_debug_errno(hid_device, SYNTHETIC_ERRNO(EINVAL),
+ "Empty report descriptor at '%s'.", desc_path);
+
+ r = is_fido_security_token_desc(desc, desc_len);
+ if (r < 0)
+ return log_device_debug_errno(hid_device, r,
+ "Failed to parse report descriptor at '%s'.", desc_path);
+ if (r > 0) {
+ printf("ID_FIDO_TOKEN=1\n");
+ printf("ID_SECURITY_TOKEN=1\n");
+ }
+
+ return 0;
+}
+
+DEFINE_MAIN_FUNCTION(run);