From b0341e1549fdec86fbe256d3f0a81c8e4ad3b573 Mon Sep 17 00:00:00 2001
From: zodiac <zodiac@0da03de8-d603-11dd-86c2-0f8696b7b6f9>
Date: Sat, 28 Feb 2009 05:34:21 +0000
Subject: [PATCH] Added fallback on old-style pty's, if /dev/pts is not
 mounted.

git-svn-id: https://shellinabox.googlecode.com/svn/trunk@73 0da03de8-d603-11dd-86c2-0f8696b7b6f9
---
 ChangeLog              |  2 ++
 config.h               |  2 +-
 shellinabox/launcher.c | 61 ++++++++++++++++++++++++++++++------------
 3 files changed, 47 insertions(+), 18 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 04ec7ad..b491dd8 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,7 @@
 2009-02-27  Markus Gutschke  <markus@shellinabox.com>
 
+	* Added fallback on old-style pty's, if /dev/pts is not mounted.
+
 	* Work-around for systems that don't define a "nogroup" group.
 
 	* Remove the dependency on fdopendir, which does not exist
diff --git a/config.h b/config.h
index 4b8d18f..6d6ff7f 100644
--- a/config.h
+++ b/config.h
@@ -95,7 +95,7 @@
 #define STDC_HEADERS 1
 
 /* Most recent revision number in the version control system */
-#define VCS_REVISION "72"
+#define VCS_REVISION "73"
 
 /* Version number of package */
 #define VERSION "2.4"
diff --git a/shellinabox/launcher.c b/shellinabox/launcher.c
index c48ed3c..82cc851 100644
--- a/shellinabox/launcher.c
+++ b/shellinabox/launcher.c
@@ -557,38 +557,65 @@ static int forkPty(int *pty, int useLogin, struct Utmp **utmp,
                    const char *peerName) {
   int slave;
   char ptyPath[PATH_MAX];
-  if ((*pty               = posix_openpt(O_RDWR|O_NOCTTY))          < 0 ||
-      grantpt(*pty)                                                 < 0 ||
-      unlockpt(*pty)                                                < 0 ||
-      ptsname_r(*pty, ptyPath, sizeof(ptyPath))                     < 0 ||
-      (slave              = NOINTR(open(ptyPath, O_RDWR|O_NOCTTY))) < 0) {
+  if ((*pty                 = posix_openpt(O_RDWR|O_NOCTTY))          < 0 ||
+      grantpt(*pty)                                                   < 0 ||
+      unlockpt(*pty)                                                  < 0 ||
+      ptsname_r(*pty, ptyPath, sizeof(ptyPath))                       < 0 ||
+      (slave                = NOINTR(open(ptyPath, O_RDWR|O_NOCTTY))) < 0) {
     if (*pty >= 0) {
       NOINTR(close(*pty));
     }
-    *pty                  = -1;
-    *utmp                 = NULL;
+
+    // Try old-style pty handling
+    char fname[40]          = "/dev/ptyXX";
+    for (const char *ptr1   = "pqrstuvwxyzabcde"; *ptr1; ptr1++) {
+      fname[8]              = *ptr1;
+      for (const char *ptr2 = "0123456789abcdef"; *ptr2; ptr2++) {
+        fname[9]            = *ptr2;
+        if ((*pty           = NOINTR(open(fname, O_RDWR, 0))) < 0) {
+          if (errno == ENOENT) {
+            goto failure;
+          }
+        }
+        grantpt(*pty);
+        unlockpt(*pty);
+        if (ptsname_r(*pty, ptyPath, sizeof(ptyPath)) < 0) {
+          strcpy(ptyPath, fname);
+          ptyPath[5]        = 't';
+        }
+        if ((slave          = NOINTR(open(ptyPath, O_RDWR|O_NOCTTY))) >= 0) {
+          debug("Opened old-style pty: %s", ptyPath);
+          goto success;
+        }
+        NOINTR(close(*pty));
+      }
+    }
+ failure:
+    *pty                    = -1;
+    *utmp                   = NULL;
     return -1;
   }
+ success:
 
   // Fill in utmp entry
-  *utmp                   = newUtmp(useLogin, ptyPath, peerName);
+  *utmp                     = newUtmp(useLogin, ptyPath, peerName);
 
   // Now, fork off the child process
   pid_t pid;
-  if ((pid                = fork()) < 0) {
+  if ((pid                  = fork()) < 0) {
     NOINTR(close(slave));
     NOINTR(close(*pty));
-    *pty                  = -1;
+    *pty                    = -1;
     deleteUtmp(*utmp);
-    *utmp                 = NULL;
+    *utmp                   = NULL;
     return -1;
   } else if (pid == 0) {
-    pid                   = getpid();
+    pid                     = getpid();
     snprintf((char *)&(*utmp)->pid[0], sizeof((*utmp)->pid), "%d", pid);
 #ifdef HAVE_UTMPX_H
-    (*utmp)->utmpx.ut_pid = pid;
+    (*utmp)->utmpx.ut_pid   = pid;
 #endif
-    (*utmp)->pty          = slave;
+    (*utmp)->pty            = slave;
 
     closeAllFds((int []){ slave }, 1);
 
@@ -607,7 +634,7 @@ static int forkPty(int *pty, int useLogin, struct Utmp **utmp,
       NOINTR(close(slave));
     }
 #endif
-    *pty                  = 0;
+    *pty                    = 0;
 
     // Force the pty to be our control terminal
     NOINTR(close(NOINTR(open(ptyPath, O_RDWR))));
@@ -616,9 +643,9 @@ static int forkPty(int *pty, int useLogin, struct Utmp **utmp,
   } else {
     snprintf((char *)&(*utmp)->pid[0], sizeof((*utmp)->pid), "%d", pid);
 #ifdef HAVE_UTMPX_H
-    (*utmp)->utmpx.ut_pid = pid;
+    (*utmp)->utmpx.ut_pid   = pid;
 #endif
-    (*utmp)->pty          = *pty;
+    (*utmp)->pty            = *pty;
     fcntl(*pty, F_SETFL, O_NONBLOCK|O_RDWR);
     NOINTR(close(slave));
     return pid;