crypto: ignore directory paths in OPENSSL_CONF

src/node.cc

@@ -102,6 +102,7 @@
 // ========== global C headers ==========
 
 #include <fcntl.h>  // _O_RDWR
+#include <sys/stat.h>
 #include <sys/types.h>
 
 #if defined(NODE_HAVE_I18N_SUPPORT)
@@ -1275,6 +1276,25 @@ InitializeOncePerProcessInternal(const std::vector<std::string>& args,
       conf_file = per_process::cli_options->openssl_config.c_str();
     }
 
+    // Ignore directories without suppressing errors in actual config files.
+    if (conf_file != nullptr) {
+      struct stat st;
+      if (stat(conf_file, &st) == 0) {
+#if defined(S_ISDIR)
+        if (S_ISDIR(st.st_mode)) {
+#else
+        if ((st.st_mode & S_IFMT) == S_IFDIR) {
+#endif
+          std::string warning = "Warning: OPENSSL_CONF path is a directory; "
+                                "ignoring: ";
+          warning += conf_file;
+          fprintf(stderr, "%s\n", warning.c_str());
+          // NULL would read OPENSSL_CONF again, including this directory.
+          conf_file = "";
+        }
+      }
+    }
+
     OPENSSL_INIT_SETTINGS* settings = OPENSSL_INIT_new();
     CHECK_NOT_NULL(settings);
     OPENSSL_INIT_set_config_filename(settings, conf_file);

test/parallel/test-openssl-config-directory.js

@@ -0,0 +1,51 @@
+'use strict';
+
+const common = require('../common');
+if (!common.hasCrypto)
+  common.skip('missing crypto');
+if (process.features.openssl_is_boringssl)
+  common.skip('BoringSSL does not use OpenSSL configuration files');
+if (!require('../common/crypto').hasOpenSSL3)
+  common.skip('requires OpenSSL 3');
+
+const assert = require('node:assert');
+const { spawnSync } = require('node:child_process');
+const { writeFileSync } = require('node:fs');
+const { join } = require('node:path');
+const tmpdir = require('../common/tmpdir');
+tmpdir.refresh();
+
+function run(conf, args = []) {
+  return spawnSync(process.execPath, [...args, '-p', '42'], {
+    encoding: 'utf8',
+    env: { ...process.env, OPENSSL_CONF: conf },
+  });
+}
+
+const directory = run(tmpdir.path);
+assert.ifError(directory.error);
+assert.strictEqual(directory.status, 0, directory.stderr);
+assert.strictEqual(directory.stdout.trim(), '42');
+assert.match(directory.stderr, /OPENSSL_CONF path is a directory; ignoring:/);
+
+const validConfig = join(tmpdir.path, 'valid.cnf');
+writeFileSync(validConfig, '');
+const overridden = run(tmpdir.path, [`--openssl-config=${validConfig}`]);
+assert.ifError(overridden.error);
+assert.strictEqual(overridden.status, 0, overridden.stderr);
+assert.strictEqual(overridden.stdout.trim(), '42');
+assert.strictEqual(overridden.stderr, '');
+
+// Ignoring a directory must not turn other configuration errors into warnings.
+const invalidConfig = join(tmpdir.path, 'invalid.cnf');
+writeFileSync(invalidConfig, '[unterminated\n');
+for (const result of [
+  run(invalidConfig),
+  run(tmpdir.path, [`--openssl-config=${invalidConfig}`]),
+]) {
+  assert.ifError(result.error);
+  assert.strictEqual(result.signal, null);
+  assert.notStrictEqual(result.status, 0);
+  assert.strictEqual(result.stdout, '');
+  assert.match(result.stderr, /OpenSSL configuration error/);
+}