components/network/hpn-ssh/patches/0018-Per-session-xauthfile.patch

   1 This patch is to fix a X11 connection failure when a user's home directory
   2 is read-only.
   3
   4 Oracle contributed back this fix to the OpenSSH upstream community. For
   5 more information, see https://bugzilla.mindrot.org/show_bug.cgi?id=2440
   6 In the future, if this fix is accepted by the upsteam in a later release, we
   7 will remove this patch when we upgrade to that release.
   8
   9 --- hpn-ssh-hpn-18.4.2/session.c.orig
  10 +++ hpn-ssh-hpn-18.4.2/session.c
  11 @@ -62,6 +62,10 @@
  12  #include <unistd.h>
  13  #include <limits.h>
  14
  15 +#ifdef PER_SESSION_XAUTHFILE
  16 +#include <libgen.h>
  17 +#endif
  18 +
  19  #include "openbsd-compat/sys-queue.h"
  20  #include "xmalloc.h"
  21  #include "ssh.h"
  22 @@ -129,6 +133,11 @@
  23
  24  static int session_pty_req(struct ssh *, Session *);
  25
  26 +#ifdef PER_SESSION_XAUTHFILE
  27 +void   session_xauthfile_cleanup(Session *);
  28 +void   cleanup_all_session_xauthfile();
  29 +#endif
  30 +
  31  /* import */
  32  extern ServerOptions options;
  33  extern char *__progname;
  34 @@ -1104,6 +1113,11 @@
  35                     auth_sock_name);
  36
  37
  38 +#ifdef PER_SESSION_XAUTHFILE
  39 +        if (s->auth_file != NULL)
  40 +                child_set_env(&env, &envsize, "XAUTHORITY", s->auth_file);
  41 +#endif
  42 +
  43         /* Set custom environment options from pubkey authentication. */
  44         if (options.permit_user_env) {
  45                 for (n = 0 ; n < auth_opts->nenv; n++) {
  46 @@ -2006,6 +2020,11 @@
  47         int r, success;
  48         u_char single_connection = 0;
  49
  50 +#ifdef PER_SESSION_XAUTHFILE
  51 +       int fd;
  52 +       char xauthdir[] = "/tmp/ssh-xauth-XXXXXX";
  53 +#endif
  54 +
  55         if (s->auth_proto != NULL || s->auth_data != NULL) {
  56                 error("session_x11_req: session %d: "
  57                     "x11 forwarding already active", s->self);
  58 @@ -2020,19 +2039,82 @@
  59
  60         s->single_connection = single_connection;
  61
  62 -       if (xauth_valid_string(s->auth_proto) &&
  63 -           xauth_valid_string(s->auth_data))
  64 -               success = session_setup_x11fwd(ssh, s);
  65 -       else {
  66 +       if (!xauth_valid_string(s->auth_proto) ||
  67 +           !xauth_valid_string(s->auth_data)) {
  68                 success = 0;
  69                 error("Invalid X11 forwarding data");
  70 +               goto out;
  71         }
  72 +
  73 +#ifdef PER_SESSION_XAUTHFILE
  74 +       /*
  75 +        * Create per session X authority file in the /tmp directory.
  76 +        *
  77 +        * If mkdtemp() or open() fails then s->auth_file remains NULL which
  78 +        * means that we won't set XAUTHORITY variable in child's environment
  79 +        * and xauth(1) will use the default location for the authority file.
  80 +        */
  81 +       temporarily_use_uid(s->pw);
  82 +       if (mkdtemp(xauthdir) != NULL) {
  83 +               s->auth_file = xmalloc(MAXPATHLEN);
  84 +               if (snprintf(s->auth_file, MAXPATHLEN, "%s/xauthfile",
  85 +                   xauthdir) >= MAXPATHLEN) {
  86 +                       error("temporary X authority file name was too long "
  87 +                           "for the buffer allocated");
  88 +                       success = 0;
  89 +                       restore_uid();
  90 +                       goto out;
  91 +               }
  92 +               /*
  93 +                * we don't want that "creating new authority file" message to
  94 +                * be printed by xauth(1) so we must create that file
  95 +                * beforehand.
  96 +                */
  97 +               if ((fd = open(s->auth_file, O_CREAT | O_EXCL | O_RDONLY,
  98 +                   S_IRUSR | S_IWUSR)) == -1) {
  99 +                       error("failed to create the temporary X authority "
 100 +                           "file %s: %.100s; will use the default one",
 101 +                           s->auth_file, strerror(errno));
 102 +                       free(s->auth_file);
 103 +                       s->auth_file = NULL;
 104 +                       if (rmdir(xauthdir) == -1) {
 105 +                               error("cannot remove xauth directory "
 106 +                                   "%s: %.100s", xauthdir, strerror(errno));
 107 +                       }
 108 +               } else {
 109 +                       if (close(fd) != 0) {
 110 +                               error("close() failed on temporary X authority "
 111 +                                   "file: %s", strerror(errno));
 112 +                               success = 0;
 113 +                               restore_uid();
 114 +                               goto out;
 115 +                       }
 116 +                       debug("temporary X authority file %s created",
 117 +                           s->auth_file);
 118 +                       debug("session number = %d", s->self);
 119 +               }
 120 +       } else {
 121 +               error("failed to create a directory for the temporary X "
 122 +                   "authority file: %.100s; will use the default xauth file",
 123 +                   strerror(errno));
 124 +       }
 125 +       restore_uid();
 126 +#endif
 127 +
 128 +       success = session_setup_x11fwd(ssh, s);
 129 +
 130 +out:
 131         if (!success) {
 132                 free(s->auth_proto);
 133                 free(s->auth_data);
 134                 s->auth_proto = NULL;
 135                 s->auth_data = NULL;
 136 +#ifdef PER_SESSION_XAUTHFILE
 137 +               free(s->auth_file);
 138 +               s->auth_file = NULL;
 139 +#endif
 140         }
 141 +
 142         return success;
 143  }
 144
 145 @@ -2312,6 +2394,51 @@
 146         PRIVSEP(session_pty_cleanup2(s));
 147  }
 148
 149 +#ifdef PER_SESSION_XAUTHFILE
 150 +/*
 151 + * We use a different temporary X authority file per session so we should
 152 + * remove those files when cleanup_exit() is called.
 153 + */
 154 +void
 155 +session_xauthfile_cleanup(Session *s)
 156 +{
 157 +       if (s == NULL || s->auth_file == NULL) {
 158 +               return;
 159 +       }
 160 +
 161 +       debug("session_xauthfile_cleanup: session %d removing %s", s->self,
 162 +           s->auth_file);
 163 +
 164 +       if (unlink(s->auth_file) == -1) {
 165 +               error("session_xauthfile_cleanup: cannot remove xauth file "
 166 +                   "%s: %.100s", s->auth_file, strerror(errno));
 167 +               return;
 168 +       }
 169 +
 170 +       /* dirname() will modify s->auth_file but that's ok */
 171 +       if (rmdir(dirname(s->auth_file)) == -1) {
 172 +               error("session_xauthfile_cleanup: "
 173 +                   "cannot remove xauth directory %s: %.100s",
 174 +                   s->auth_file, strerror(errno));
 175 +               return;
 176 +       }
 177 +       free(s->auth_file);
 178 +       s->auth_file = NULL;
 179 +}
 180 +
 181 +/*
 182 + * This is called by do_cleanup() when cleanup_exit() is called.
 183 + */
 184 +void
 185 +cleanup_all_session_xauthfile()
 186 +{
 187 +       int i;
 188 +       for (i = 0; i < sessions_nalloc; i++) {
 189 +                session_xauthfile_cleanup(&sessions[i]);
 190 +       }
 191 +}
 192 +#endif
 193 +
 194  static char *
 195  sig2name(int sig)
 196  {
 197 @@ -2459,6 +2586,9 @@
 198         free(s->auth_display);
 199         free(s->auth_data);
 200         free(s->auth_proto);
 201 +#ifdef PER_SESSION_XAUTHFILE
 202 +       session_xauthfile_cleanup(s);
 203 +#endif
 204         free(s->subsys);
 205         if (s->env != NULL) {
 206                 for (i = 0; i < s->num_env; i++) {
 207 @@ -2714,6 +2844,10 @@
 208                 auth_info_file = NULL;
 209         }
 210
 211 +#ifdef PER_SESSION_XAUTHFILE
 212 +       cleanup_all_session_xauthfile();
 213 +#endif
 214 +
 215         /*
 216          * Cleanup ptys/utmp only if privsep is disabled,
 217          * or if running in monitor.
 218 --- hpn-ssh-hpn-18.4.2/session.h.orig
 219 +++ hpn-ssh-hpn-18.4.2/session.h
 220 @@ -50,6 +50,9 @@
 221         char    *auth_display;
 222         char    *auth_proto;
 223         char    *auth_data;
 224 +#ifdef PER_SESSION_XAUTHFILE
 225 +       char    *auth_file;     /* xauth(1) authority file */
 226 +#endif
 227         int     single_connection;
 228
 229         int     chanid;