CWRU/audit-patch

   1 Date: Tue, 06 Feb 2007 16:06:58 -0500
   2 From: Steve Grubb <sgrubb@redhat.com>
   3 Subject: Re: bash and linux audit
   4 To: chet.ramey@case.edu
   5 Organization: Red Hat
   6
   7 OK, I released audit 1.4 Sunday which has the logging function for user
   8 commands. It produces audit events like this:
   9
  10 type=USER_CMD msg=audit(01/30/2007 18:23:45.793:143) : user pid=22862 uid=root
  11 auid=root subj=system_u:system_r:unconfined_t:s0-s0:c0.c1023
  12 msg='cwd=/root/test dir cmd=ls -l (terminal=tty1 res=success)'
  13
  14 diff -urp bash-3.2.orig/config-bot.h bash-3.2/config-bot.h
  15 --- bash-3.2.orig/config-bot.h  2007-01-03 09:01:05.000000000 -0500
  16 +++ bash-3.2/config-bot.h       2007-01-20 11:59:23.000000000 -0500
  17 @@ -97,6 +97,11 @@
  18  #  define RESTRICTED_SHELL_NAME "rbash"
  19  #endif
  20
  21 +/* If the shell is called by this name, it will become audited. */
  22 +#if defined (AUDIT_SHELL)
  23 +#  define AUDIT_SHELL_NAME "aubash"
  24 +#endif
  25 +
  26  /***********************************************************/
  27  /* Make sure feature defines have necessary prerequisites. */
  28  /***********************************************************/
  29 diff -urp bash-3.2.orig/config.h.in bash-3.2/config.h.in
  30 --- bash-3.2.orig/config.h.in   2007-01-03 09:01:05.000000000 -0500
  31 +++ bash-3.2/config.h.in        2007-01-20 11:59:23.000000000 -0500
  32 @@ -81,6 +81,11 @@
  33     flag. */
  34  #undef RESTRICTED_SHELL
  35
  36 +/* Define AUDIT_SHELL if you want the generated shell to audit all
  37 +   actions performed by root account.  The shell thus generated can become
  38 +   audited by being run with the name "aubash". */
  39 +#undef AUDIT_SHELL
  40 +
  41  /* Define DISABLED_BUILTINS if you want "builtin foo" to always run the
  42     shell builtin "foo", even if it has been disabled with "enable -n foo". */
  43  #undef DISABLED_BUILTINS
  44 diff -urp bash-3.2.orig/configure.in bash-3.2/configure.in
  45 --- bash-3.2.orig/configure.in  2007-01-03 09:01:05.000000000 -0500
  46 +++ bash-3.2/configure.in       2007-01-20 11:59:23.000000000 -0500
  47 @@ -162,6 +162,7 @@ opt_history=yes
  48  opt_bang_history=yes
  49  opt_dirstack=yes
  50  opt_restricted=yes
  51 +opt_audit=yes
  52  opt_process_subst=yes
  53  opt_prompt_decoding=yes
  54  opt_select=yes
  55 @@ -195,8 +196,8 @@ dnl a minimal configuration turns everyt
  56  dnl added individually
  57  if test $opt_minimal_config = yes; then
  58         opt_job_control=no opt_alias=no opt_readline=no
  59 -       opt_history=no opt_bang_history=no opt_dirstack=no
  60 -       opt_restricted=no opt_process_subst=no opt_prompt_decoding=no
  61 +       opt_history=no opt_bang_history=no opt_dirstack=no opt_restricted=no
  62 +       opt_audit=no opt_process_subst=no opt_prompt_decoding=no
  63         opt_select=no opt_help=no opt_array_variables=no opt_dparen_arith=no
  64         opt_brace_expansion=no opt_disabled_builtins=no opt_command_timing=no
  65         opt_extended_glob=no opt_cond_command=no opt_arith_for_command=no
  66 @@ -227,6 +228,7 @@ AC_ARG_ENABLE(progcomp, AC_HELP_STRING([
  67  AC_ARG_ENABLE(prompt-string-decoding, AC_HELP_STRING([--enable-prompt-string-decoding], [turn on escape character decoding in prompts]), opt_prompt_decoding=$enableval)
  68  AC_ARG_ENABLE(readline, AC_HELP_STRING([--enable-readline], [turn on command line editing]), opt_readline=$enableval)
  69  AC_ARG_ENABLE(restricted, AC_HELP_STRING([--enable-restricted], [enable a restricted shell]), opt_restricted=$enableval)
  70 +AC_ARG_ENABLE(audit, AC_HELP_STRING([--enable-audit], [enable an audited shell]), opt_audit=$enableval)
  71  AC_ARG_ENABLE(select, AC_HELP_STRING([--enable-select], [include select command]), opt_select=$enableval)
  72  AC_ARG_ENABLE(separate-helpfiles, AC_HELP_STRING([--enable-separate-helpfiles], [use external files for help builtin documentation]), opt_separate_help=$enableval)
  73  AC_ARG_ENABLE(single-help-strings, AC_HELP_STRING([--enable-single-help-strings], [store help documentation as a single string to ease translation]), opt_single_longdoc_strings=$enableval)
  74 @@ -254,6 +256,10 @@ fi
  75  if test $opt_restricted = yes; then
  76  AC_DEFINE(RESTRICTED_SHELL)
  77  fi
  78 +if test $opt_audit = yes; then
  79 +AC_DEFINE(AUDIT_SHELL)
  80 +AUDIT_LIB='-laudit'
  81 +fi
  82  if test $opt_process_subst = yes; then
  83  AC_DEFINE(PROCESS_SUBSTITUTION)
  84  fi
  85 @@ -355,6 +361,8 @@ AC_SUBST(HELPDIRDEFINE)
  86  AC_SUBST(HELPINSTALL)
  87  AC_SUBST(HELPSTRINGS)
  88
  89 +AC_SUBST(AUDIT_LIB)
  90 +
  91  echo ""
  92  echo "Beginning configuration for bash-$BASHVERS-$RELSTATUS for ${host_cpu}-${host_vendor}-${host_os}"
  93  echo ""
  94 diff -urp bash-3.2.orig/doc/bash.1 bash-3.2/doc/bash.1
  95 --- bash-3.2.orig/doc/bash.1    2007-01-03 09:01:05.000000000 -0500
  96 +++ bash-3.2/doc/bash.1 2007-01-20 11:59:23.000000000 -0500
  97 @@ -155,6 +155,12 @@ single-character options to be recognize
  98  .PP
  99  .PD 0
 100  .TP
 101 +.B \-\-audit
 102 +The shell logs all commands run by the root user (see
 103 +.SM
 104 +.B "AUDIT SHELL"
 105 +below).
 106 +.TP
 107  .B \-\-debugger
 108  Arrange for the debugger profile to be executed before the shell
 109  starts.
 110 @@ -8770,6 +8776,17 @@ turns off any restrictions in the shell
 111  script.
 112  .\" end of rbash.1
 113  .if \n(zY=1 .ig zY
 114 +.SH "AUDIT SHELL"
 115 +.zY
 116 +.PP
 117 +If
 118 +.B bash
 119 +is started with the name
 120 +.BR aubash ,
 121 +or the
 122 +.B \-\-audit
 123 +option is supplied at invocation, the shell logs all commands issued by the root user to the audit system.
 124 +.if \n(zY=1 .ig zY
 125  .SH "SEE ALSO"
 126  .PD 0
 127  .TP
 128 diff -urp bash-3.2.orig/eval.c bash-3.2/eval.c
 129 --- bash-3.2.orig/eval.c        2007-01-03 09:01:06.000000000 -0500
 130 +++ bash-3.2/eval.c     2007-01-20 11:59:23.000000000 -0500
 131 @@ -45,6 +45,11 @@
 132  #  include "bashhist.h"
 133  #endif
 134
 135 +#if defined (AUDIT_SHELL)
 136 +#  include <libaudit.h>
 137 +#  include <errno.h>
 138 +#endif
 139 +
 140  extern int EOF_reached;
 141  extern int indirection_level;
 142  extern int posixly_correct;
 143 @@ -58,6 +63,38 @@ extern int rpm_requires;
 144  static void send_pwd_to_eterm __P((void));
 145  static sighandler alrm_catcher __P((int));
 146
 147 +#if defined (AUDIT_SHELL)
 148 +static int audit_fd = -1;
 149 +
 150 +static int
 151 +audit_start ()
 152 +{
 153 +  audit_fd = audit_open ();
 154 +  if (audit_fd < 0)
 155 +    return -1;
 156 +  else
 157 +    return 0;
 158 +}
 159 +
 160 +static int
 161 +audit (cmd, result)
 162 +        char *cmd;
 163 +        int result;
 164 +{
 165 +  int rc;
 166 +
 167 +  if (audit_fd < 0)
 168 +    return 0;
 169 +
 170 +  rc = audit_log_user_command (audit_fd, AUDIT_USER_CMD, cmd,
 171 +                               NULL, !result);
 172 +  close (audit_fd);
 173 +  audit_fd = -1;
 174 +  return rc;
 175 +}
 176 +#endif
 177 +
 178 +
 179  /* Read and execute commands until EOF is reached.  This assumes that
 180     the input source has already been initialized. */
 181  int
 182 @@ -145,7 +182,25 @@ reader_loop ()
 183
 184               executing = 1;
 185               stdin_redir = 0;
 186 +#if defined (AUDIT_SHELL)
 187 +              if (audited && interactive_shell && getuid () == 0)
 188 +                {
 189 +                  if (audit_start () < 0)
 190 +                    {
 191 +                      if (errno != EINVAL && errno != EPROTONOSUPPORT &&
 192 +                          errno != EAFNOSUPPORT)
 193 +                        return EXECUTION_FAILURE;
 194 +                    }
 195 +                }
 196 +#endif
 197 +
 198               execute_command (current_command);
 199 +#if defined (AUDIT_SHELL)
 200 +              {
 201 +                extern char *shell_input_line;
 202 +                audit (shell_input_line, last_command_exit_value);
 203 +              }
 204 +#endif
 205
 206             exec_done:
 207               QUIT;
 208 diff -urp bash-3.2.orig/externs.h bash-3.2/externs.h
 209 --- bash-3.2.orig/externs.h     2007-01-03 09:01:06.000000000 -0500
 210 +++ bash-3.2/externs.h  2007-01-20 12:05:00.000000000 -0500
 211 @@ -77,6 +77,10 @@ extern int shell_is_restricted __P((char
 212  extern int maybe_make_restricted __P((char *));
 213  #endif
 214
 215 +#if defined (AUDIT_SHELL)
 216 +extern int maybe_make_audited __P((char *));
 217 +#endif
 218 +
 219  extern void unset_bash_input __P((int));
 220  extern void get_current_user_info __P((void));
 221
 222 diff -urp bash-3.2.orig/flags.c bash-3.2/flags.c
 223 --- bash-3.2.orig/flags.c       2007-01-03 09:01:06.000000000 -0500
 224 +++ bash-3.2/flags.c    2007-01-20 11:59:23.000000000 -0500
 225 @@ -142,6 +142,12 @@ int restricted = 0;                /* currently restri
 226  int restricted_shell = 0;      /* shell was started in restricted mode. */
 227  #endif /* RESTRICTED_SHELL */
 228
 229 +#if defined (AUDIT_SHELL)
 230 +/* Non-zero means that this shell is audited. An audited shell records
 231 +   each command that the root user executes. */
 232 +int audited = 0;               /* shell was started in audit mode. */
 233 +#endif /* AUDIT_SHELL */
 234 +
 235  /* Non-zero means that this shell is running in `privileged' mode.  This
 236     is required if the shell is to run setuid.  If the `-p' option is
 237     not supplied at startup, and the real and effective uids or gids
 238 diff -urp bash-3.2.orig/flags.h bash-3.2/flags.h
 239 --- bash-3.2.orig/flags.h       2007-01-03 09:01:06.000000000 -0500
 240 +++ bash-3.2/flags.h    2007-01-20 11:59:23.000000000 -0500
 241 @@ -66,6 +66,10 @@ extern int restricted;
 242  extern int restricted_shell;
 243  #endif /* RESTRICTED_SHELL */
 244
 245 +#if defined (AUDIT_SHELL)
 246 +extern int audited;
 247 +#endif /* AUDIT_SHELL */
 248 +
 249  extern int *find_flag __P((int));
 250  extern int change_flag __P((int, int));
 251  extern char *which_set_flags __P((void));
 252 Only in bash-3.2: .made
 253 diff -urp bash-3.2.orig/Makefile.in bash-3.2/Makefile.in
 254 --- bash-3.2.orig/Makefile.in   2007-01-03 09:01:06.000000000 -0500
 255 +++ bash-3.2/Makefile.in        2007-01-20 11:59:23.000000000 -0500
 256 @@ -366,6 +366,8 @@ MALLOC_LIBRARY = @MALLOC_LIBRARY@
 257  MALLOC_LDFLAGS = @MALLOC_LDFLAGS@
 258  MALLOC_DEP = @MALLOC_DEP@
 259
 260 +AUDIT_LIB = @AUDIT_LIB@
 261 +
 262  ALLOC_HEADERS = $(ALLOC_LIBSRC)/getpagesize.h $(ALLOC_LIBSRC)/shmalloc.h \
 263                 $(ALLOC_LIBSRC)/imalloc.h $(ALLOC_LIBSRC)/mstats.h \
 264                 $(ALLOC_LIBSRC)/table.h $(ALLOC_LIBSRC)/watch.h
 265 @@ -386,7 +388,7 @@ BASHINCFILES =       $(BASHINCDIR)/posixstat.
 266                  $(BASHINCDIR)/ocache.h
 267
 268  LIBRARIES = $(SHLIB_LIB) $(READLINE_LIB) $(HISTORY_LIB) $(TERMCAP_LIB) $(GLOB_LIB) \
 269 -           $(TILDE_LIB) $(MALLOC_LIB) $(INTL_LIB) $(LOCAL_LIBS)
 270 +           $(TILDE_LIB) $(MALLOC_LIB) $(INTL_LIB) $(LOCAL_LIBS) $(AUDIT_LIB)
 271
 272  LIBDEP = $(SHLIB_DEP) $(INTL_DEP) $(READLINE_DEP) $(HISTORY_DEP) $(TERMCAP_DEP) $(GLOB_DEP) \
 273          $(TILDE_DEP) $(MALLOC_DEP)
 274 diff -urp bash-3.2.orig/parse.y bash-3.2/parse.y
 275 --- bash-3.2.orig/parse.y       2007-01-03 09:01:06.000000000 -0500
 276 +++ bash-3.2/parse.y    2007-01-20 11:59:23.000000000 -0500
 277 @@ -258,7 +258,7 @@ int need_here_doc;
 278
 279  /* Where shell input comes from.  History expansion is performed on each
 280     line when the shell is interactive. */
 281 -static char *shell_input_line = (char *)NULL;
 282 +char *shell_input_line = (char *)NULL;
 283  static int shell_input_line_index;
 284  static int shell_input_line_size;      /* Amount allocated for shell_input_line. */
 285  static int shell_input_line_len;       /* strlen (shell_input_line) */
 286 diff -urp bash-3.2.orig/shell.c bash-3.2/shell.c
 287 --- bash-3.2.orig/shell.c       2007-01-03 09:01:06.000000000 -0500
 288 +++ bash-3.2/shell.c    2007-01-20 12:04:23.000000000 -0500
 289 @@ -240,6 +240,9 @@ struct {
 290  #if defined (RESTRICTED_SHELL)
 291    { "restricted", Int, &restricted, (char **)0x0 },
 292  #endif
 293 +#if defined (AUDIT_SHELL)
 294 +  { "audit", Int, &audited, (char **)0x0 },
 295 +#endif
 296    { "verbose", Int, &echo_input_at_read, (char **)0x0 },
 297    { "version", Int, &do_version, (char **)0x0 },
 298    { "wordexp", Int, &wordexp_only, (char **)0x0 },
 299 @@ -644,6 +647,10 @@ main (argc, argv, env)
 300      maybe_make_restricted (shell_name);
 301  #endif /* RESTRICTED_SHELL */
 302
 303 +#if defined (AUDIT_SHELL)
 304 +    maybe_make_audited (shell_name);
 305 +#endif
 306 +
 307    if (wordexp_only)
 308      {
 309        startup_state = 3;
 310 @@ -1143,6 +1150,29 @@ maybe_make_restricted (name)
 311  }
 312  #endif /* RESTRICTED_SHELL */
 313
 314 +#if defined (AUDIT_SHELL)
 315 +/* Perhaps make this shell an `audited' one, based on NAME.  If the
 316 +   basename of NAME is "aubash", then this shell is audited.  The
 317 +   name of the audited shell is a configurable option, see config.h.
 318 +   In an audited shell, all actions performed by root will be logged
 319 +   to the audit system.
 320 +   Do this also if `audited' is already set to 1 maybe the shell was
 321 +   started with --audit. */
 322 +int
 323 +maybe_make_audited (name)
 324 +     char *name;
 325 +{
 326 +  char *temp;
 327 +
 328 +  temp = base_pathname (name);
 329 +  if (*temp == '-')
 330 +    temp++;
 331 +  if (audited || (STREQ (temp, AUDIT_SHELL_NAME)))
 332 +    audited = 1;
 333 +  return (audited);
 334 +}
 335 +#endif /* AUDIT_SHELL */
 336 +
 337  /* Fetch the current set of uids and gids and return 1 if we're running
 338     setuid or setgid. */
 339  static int