knownhosts: Use ssh_mkdirs() instead of ssh_mkdir()

Previously, if the path to known_hosts file set through
SSH_OPTIONS_KNOWNHOSTS included missing directories,
ssh_session_update_known_hosts() would fail.  The added test case checks
that this is not the case anymore.

The logic of checking if the directory is accessible before creating it
was replaced by creating the directory if opening the file failed.  This
is to minimize the risk of TOCTOU race conditions.

Fixes: T166

Signed-off-by: Anderson Toshiyuki Sasaki <ansasaki@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>

1 files changed, 42 insertions, 0 deletions

diff --git a/tests/client/torture_knownhosts_verify.c b/tests/client/torture_knownhosts_verify.c
index df8363e2..2a2a6b64 100644
--- a/tests/client/torture_knownhosts_verify.c
+++ b/tests/client/torture_knownhosts_verify.c
@@ -35,6 +35,8 @@
 
 #define BAD_RSA "AAAAB3NzaC1yc2EAAAADAQABAAABAQDXvXuawzaArEwkLIXTz/EWywLOCtqQL3P9yKkrhz6AplXP2PhOh5pyxa1VfGKe453jNeYBJ0ROto3BshXgZXbo86oLXTkbe0gO5xi3r5WjXxjOFvRRTLot5fPLNDOv9+TnsPmkNn0iIeyPnfrcPIyjWt5zSWUfkNC8oNHxsiSshjpbJvTXSDipukpUy41d7jg4uWGuonMTF7yu7HfuHqq7lhb0WlwSpfbqAbfYARBddcdcARyhix4RMWZZqVY20H3Vsjq8bjKC+NJXFce1PRg+qcOWQdlXEei4dkzAvHvfQRx1TjzkrBZ6B6thmZtyeb9IsiB0tg2g0JN2VTAGkxqp"
 
+const char template[] = "temp_dir_XXXXXX";
+
 static int sshd_group_setup(void **state)
 {
     torture_setup_sshd_server(state, false);
@@ -414,6 +416,43 @@ static void torture_knownhosts_conflict(void **state)
     /* session will be freed by session_teardown() */
 }
 
+static void torture_knownhosts_new_file(void **state)
+{
+    struct torture_state *s = *state;
+    ssh_session session = s->ssh.session;
+    enum ssh_known_hosts_e found;
+    int rc;
+
+    char new_known_hosts[256];
+    char *tmp_dir = NULL;
+    ssize_t count = 0;
+
+    /* Create a disposable directory */
+    tmp_dir = torture_make_temp_dir(template);
+    assert_non_null(tmp_dir);
+
+    count = snprintf(new_known_hosts, sizeof(new_known_hosts),
+                     "%s/a/b/c/d/known_hosts", tmp_dir);
+    assert_return_code(count, errno);
+
+    rc = ssh_options_set(session, SSH_OPTIONS_KNOWNHOSTS, new_known_hosts);
+    assert_ssh_return_code(session, rc);
+
+    rc = ssh_connect(session);
+    assert_ssh_return_code(session, rc);
+
+    rc = ssh_session_update_known_hosts(session);
+    assert_ssh_return_code(session, rc);
+
+    found = ssh_session_is_known_server(session);
+    assert_int_equal(found, SSH_KNOWN_HOSTS_OK);
+
+    /* Cleanup */
+    torture_rmdirs(tmp_dir);
+
+    SAFE_FREE(tmp_dir);
+}
+
 int torture_run_tests(void) {
     int rc;
     struct CMUnitTest tests[] = {
@@ -438,6 +477,9 @@ int torture_run_tests(void) {
         cmocka_unit_test_setup_teardown(torture_knownhosts_duplicate,
                                         session_setup,
                                         session_teardown),
+        cmocka_unit_test_setup_teardown(torture_knownhosts_new_file,
+                                        session_setup,
+                                        session_teardown),
     };
 
     ssh_init();