pytest: reproduce issue #4302

Signed-off-by: Antoine Poinsot <darosior@protonmail.com>

tests/test_wallet.py

@@ -1097,6 +1097,39 @@ def test_hsmtool_dump_descriptors(node_factory, bitcoind):
     assert len(bitcoind.rpc.listunspent(1, 1, [addr])) == 1
 
 
+@pytest.mark.xfail(strict=True)
+@unittest.skipIf(VALGRIND, "It does not play well with prompt and key derivation.")
+def test_hsmtool_generatehsm(node_factory):
+    l1 = node_factory.get_node()
+    l1.stop()
+    hsm_path = os.path.join(l1.daemon.lightning_dir, TEST_NETWORK,
+                            "hsm_secret")
+    master_fd, slave_fd = os.openpty()
+
+    hsmtool = HsmTool("generatehsm", hsm_path)
+    # You cannot re-generate an already existing hsm_secret
+    hsmtool.start(stdin=slave_fd, stdout=subprocess.PIPE,
+                  stderr=subprocess.PIPE)
+    assert hsmtool.proc.wait(5) == 2
+    os.remove(hsm_path)
+
+    # We can generate a valid hsm_secret from a wordlist and a "passphrase"
+    hsmtool.start(stdin=slave_fd, stdout=subprocess.PIPE,
+                  stderr=subprocess.PIPE)
+    hsmtool.wait_for_log(r"Select your language:")
+    os.write(master_fd, "0\n".encode("utf-8"))
+    hsmtool.wait_for_log(r"Introduce your BIP39 word list")
+    os.write(master_fd, "ritual idle hat sunny universe pluck key alpha wing "
+                        "cake have wedding\n".encode("utf-8"))
+    hsmtool.wait_for_log(r"Enter your passphrase:")
+    os.write(master_fd, "This is actually not a passphrase\n".encode("utf-8"))
+    hsmtool.proc.wait(5)
+    hsmtool.is_in_log(r"New hsm_secret file created")
+
+    # We can start the node with this hsm_secret
+    l1.start()
+
+
 # this test does a 'listtransactions' on a yet unconfirmed channel
 def test_fundchannel_listtransaction(node_factory, bitcoind):
     l1, l2 = node_factory.get_nodes(2)

tools/hsmtool.c

@@ -461,6 +461,7 @@ static void get_words(struct words **words) {
 		printf("  %zu) %s (%s)\n", i, languages[i].name, languages[i].abbr);
 	}
 	printf("Select [0-%zu]: ", ARRAY_SIZE(languages));
+	fflush(stdout);
 
 	char *selected = NULL;
 	size_t size = 0;
@@ -483,6 +484,7 @@ static void get_mnemonic(char *mnemonic) {
 	size_t line_size = 0;
 
 	printf("Introduce your BIP39 word list separated by space:\n");
+	fflush(stdout);
 	size_t characters = getline(&line, &line_size, stdin);
 	if (characters < 0)
 		errx(ERROR_USAGE, "Could not read line from stdin.");