Bluetooth: Expose current list of link keys via debugfs

For debugging purposes expose the current list of link keys via
debugfs. This file is read-only and limited to root access.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>

1 files changed, 30 insertions, 0 deletions

diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index 3ef5fdde8437..ee946cb26906 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -187,6 +187,34 @@ static const struct file_operations inquiry_cache_fops = {
         .release        = single_release,
 };
 
+static int link_keys_show(struct seq_file *f, void *ptr)
+{
+        struct hci_dev *hdev = f->private;
+        struct list_head *p, *n;
+
+        hci_dev_lock(hdev);
+        list_for_each_safe(p, n, &hdev->link_keys) {
+                struct link_key *key = list_entry(p, struct link_key, list);
+                seq_printf(f, "%pMR %u %*phN %u\n", &key->bdaddr, key->type,
+                           HCI_LINK_KEY_SIZE, key->val, key->pin_len);
+        }
+        hci_dev_unlock(hdev);
+
+        return 0;
+}
+
+static int link_keys_open(struct inode *inode, struct file *file)
+{
+        return single_open(file, link_keys_show, inode->i_private);
+}
+
+static const struct file_operations link_keys_fops = {
+        .open           = link_keys_open,
+        .read           = seq_read,
+        .llseek         = seq_lseek,
+        .release        = single_release,
+};
+
 static int dev_class_show(struct seq_file *f, void *ptr)
 {
         struct hci_dev *hdev = f->private;
@@ -1067,6 +1095,8 @@ static int __hci_init(struct hci_dev *hdev)
         if (lmp_bredr_capable(hdev)) {
                 debugfs_create_file("inquiry_cache", 0444, hdev->debugfs,
                                     hdev, &inquiry_cache_fops);
+                debugfs_create_file("link_keys", 0400, hdev->debugfs,
+                                    hdev, &link_keys_fops);
                 debugfs_create_file("dev_class", 0444, hdev->debugfs,
                                     hdev, &dev_class_fops);
                 debugfs_create_file("voice_setting", 0444, hdev->debugfs,