- /*
- * Check if the user is logging in as root and root logins
- * are disallowed.
- * Note that root login is allowed for forced commands.
- */
- if (authenticated && pw->pw_uid == 0 && !options.permit_root_login) {
- if (forced_command) {
- log("Root login accepted for forced command.");
- } else {
- authenticated = 0;
- log("ROOT LOGIN REFUSED FROM %.200s",
- get_canonical_hostname());
- }
- }
-
- /* Raise logging level */
- if (authenticated ||
- attempt == AUTH_FAIL_LOG ||
- type == SSH_CMSG_AUTH_PASSWORD)
- authlog = log;
-
- authlog("%s %s for %.200s from %.200s port %d%s",
- authenticated ? "Accepted" : "Failed",
- get_authname(type),
- pw->pw_uid == 0 ? "ROOT" : pw->pw_name,
- get_remote_ipaddr(),
- get_remote_port(),
- user);
-
-#ifdef USE_PAM
- if (authenticated) {
- if (!do_pam_account(pw->pw_name, client_user)) {
- if (client_user != NULL) {
- xfree(client_user);
- client_user = NULL;
- }
- do_fake_authloop1(pw->pw_name);
- }
- return;
+/*
+ * Check a given file for security. This is defined as all components
+ * of the path to the file must be owned by either the owner of
+ * of the file or root and no directories must be group or world writable.
+ *
+ * XXX Should any specific check be done for sym links ?
+ *
+ * Takes an open file descriptor, the file name, a uid and and
+ * error buffer plus max size as arguments.
+ *
+ * Returns 0 on success and -1 on failure
+ */
+int
+secure_filename(FILE *f, const char *file, struct passwd *pw,
+ char *err, size_t errlen)
+{
+ uid_t uid = pw->pw_uid;
+ char buf[MAXPATHLEN], homedir[MAXPATHLEN];
+ char *cp;
+ int comparehome = 0;
+ struct stat st;
+
+ if (realpath(file, buf) == NULL) {
+ snprintf(err, errlen, "realpath %s failed: %s", file,
+ strerror(errno));
+ return -1;
+ }
+ if (realpath(pw->pw_dir, homedir) != NULL)
+ comparehome = 1;
+
+ /* check the open file to avoid races */
+ if (fstat(fileno(f), &st) < 0 ||
+ (st.st_uid != 0 && st.st_uid != uid) ||
+ (st.st_mode & 022) != 0) {
+ snprintf(err, errlen, "bad ownership or modes for file %s",
+ buf);
+ return -1;
+ }
+
+ /* for each component of the canonical path, walking upwards */
+ for (;;) {
+ if ((cp = dirname(buf)) == NULL) {
+ snprintf(err, errlen, "dirname() failed");
+ return -1;