Merge bitcoin#10885: Reject invalid wallets

d84e78e [wallet] Specify wallet name in wallet loading errors (John Newbery)
a6da027 Reject invalid wallet files (João Barbosa)
3ef77a0 Reject duplicate wallet filenames (João Barbosa)

Pull request description:

  This PR prevents loading the same wallet more than once in a multi wallet scenario. It also prevents loading with invalid files: non regular files or symlinks.

Tree-SHA512: 45bf814096bb788db1c76ff334e679a10686cee7d9c8cd48fe5d924031353ace271f6fb0d4af49a34246d336945515c176920a552be7b9fbe07ab8e00e5f6e5e

src/wallet/wallet.cpp

@@ -611,11 +611,26 @@ bool CWallet::Verify()
 
     uiInterface.InitMessage(_("Verifying wallet(s)..."));
 
+    // Keep track of each wallet absolute path to detect duplicates.
+    std::set<fs::path> wallet_paths;
+
     for (const std::string& walletFile : gArgs.GetArgs("-wallet")) {
         if (boost::filesystem::path(walletFile).filename() != walletFile) {
-            return InitError(_("-wallet parameter must only specify a filename (not a path)"));
-        } else if (SanitizeString(walletFile, SAFE_CHARS_FILENAME) != walletFile) {
-            return InitError(_("Invalid characters in -wallet filename"));
+            return InitError(strprintf(_("Error loading wallet %s. -wallet parameter must only specify a filename (not a path)."), walletFile));
+        }
+
+        if (SanitizeString(walletFile, SAFE_CHARS_FILENAME) != walletFile) {
+            return InitError(strprintf(_("Error loading wallet %s. Invalid characters in -wallet filename."), walletFile));
+        }
+
+        fs::path wallet_path = fs::absolute(walletFile, GetDataDir());
+
+        if (fs::exists(wallet_path) && (!fs::is_regular_file(wallet_path) || fs::is_symlink(wallet_path))) {
+            return InitError(strprintf(_("Error loading wallet %s. -wallet filename must be a regular file."), walletFile));
+        }
+
+        if (!wallet_paths.insert(wallet_path).second) {
+            return InitError(strprintf(_("Error loading wallet %s. Duplicate -wallet filename specified."), walletFile));
         }
 
         std::string strError;

test/functional/multiwallet.py

@@ -6,6 +6,8 @@
 
 Verify that a bitcoind node can load multiple wallet files
 """
+import os
+
 from test_framework.test_framework import BitcoinTestFramework
 from test_framework.util import assert_equal, assert_raises_jsonrpc
 
@@ -18,6 +20,21 @@ def __init__(self):
         self.extra_args = [['-wallet=w1', '-wallet=w2', '-wallet=w3']]
 
     def run_test(self):
+        self.stop_node(0)
+
+        # should not initialize if there are duplicate wallets
+        self.assert_start_raises_init_error(0, self.options.tmpdir, ['-wallet=w1', '-wallet=w1'], 'Error loading wallet w1. Duplicate -wallet filename specified.')
+
+        # should not initialize if wallet file is a directory
+        os.mkdir(os.path.join(self.options.tmpdir, 'node0', 'regtest', 'w11'))
+        self.assert_start_raises_init_error(0, self.options.tmpdir, ['-wallet=w11'], 'Error loading wallet w11. -wallet filename must be a regular file.')
+
+        # should not initialize if wallet file is a symlink
+        os.symlink(os.path.join(self.options.tmpdir, 'node0', 'regtest', 'w1'), os.path.join(self.options.tmpdir, 'node0', 'regtest', 'w12'))
+        self.assert_start_raises_init_error(0, self.options.tmpdir, ['-wallet=w12'], 'Error loading wallet w12. -wallet filename must be a regular file.')
+
+        self.nodes[0] = self.start_node(0, self.options.tmpdir, self.extra_args[0])
+
         w1 = self.nodes[0] / "wallet/w1"
         w1.generate(1)