summaryrefslogtreecommitdiff
path: root/procfs/main.c
blob: 509f4883d7b4454b248b10d4b0ad3bc06a54e49b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
/* Hurd /proc filesystem, main program.
   Copyright (C) 2010 Free Software Foundation, Inc.

   This file is part of the GNU Hurd.

   The GNU Hurd is free software; you can redistribute it and/or
   modify it under the terms of the GNU General Public License as
   published by the Free Software Foundation; either version 2, or (at
   your option) any later version.

   The GNU Hurd is distributed in the hope that it will be useful, but
   WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */

#include <mach.h>
#include <hurd.h>
#include <unistd.h>
#include <error.h>
#include <argp.h>
#include <argz.h>
#include <hurd/netfs.h>
#include <ps.h>
#include <pids.h>
#include "procfs.h"
#include "proclist.h"
#include "rootdir.h"
#include "dircat.h"
#include "main.h"

/* Command-line options */
int opt_clk_tck;
mode_t opt_stat_mode;
pid_t opt_fake_self;
pid_t opt_kernel_pid;
uid_t opt_anon_owner;

/* Default values */
#define OPT_CLK_TCK    sysconf(_SC_CLK_TCK)
#define OPT_STAT_MODE  0400
#define OPT_FAKE_SELF  -1
#define OPT_KERNEL_PID HURD_PID_KERNEL
#define OPT_ANON_OWNER 0

#define NODEV_KEY  -1 /* <= 0, so no short option. */
#define NOEXEC_KEY -2 /* Likewise. */
#define NOSUID_KEY -3 /* Likewise. */

static error_t
argp_parser (int key, char *arg, struct argp_state *state)
{
  struct passwd *pw;
  char *endp;
  long int v;

  switch (key)
  {
    case 'h':
      v = strtol (arg, &endp, 0);
      if (*endp || ! *arg || v <= 0)
	argp_error (state, "--clk-tck: HZ should be a positive integer");
      else
	opt_clk_tck = v;
      break;

    case 's':
      v = strtol (arg, &endp, 8);
      if (*endp || ! *arg || (mode_t) v & ~07777)
	argp_error (state, "--stat-mode: MODE should be an octal mode");
      else
	opt_stat_mode = v;
      break;

    case 'S':
      if (arg)
        {
	  v = strtol (arg, &endp, 0);
	  if (*endp || ! *arg)
	    argp_error (state, "--fake-self: PID must be an integer");
	  else
	    opt_fake_self = v;
	}
      else
	opt_fake_self = 1;
      break;

    case 'k':
      v = strtol (arg, &endp, 0);
      if (*endp || ! *arg || (signed) opt_kernel_pid < 0)
	argp_error (state, "--kernel-process: PID must be a positive integer");
      else
	opt_kernel_pid = v;
      break;

    case 'c':
      opt_clk_tck = 100;
      opt_stat_mode = 0444;
      opt_fake_self = 1;
      break;

    case 'a':
      pw = getpwnam (arg);
      if (pw)
	{
	  opt_anon_owner = pw->pw_uid;
	  break;
	}

      v = strtol (arg, &endp, 0);
      if (*endp || ! *arg || v < 0)
	argp_error (state, "--anonymous-owner: USER should be "
		    "a user name or a numeric UID.");
      else
	opt_anon_owner = v;
      break;

    case NODEV_KEY:
      /* Ignored for compatibility with Linux' procfs. */
      break;

    case NOEXEC_KEY:
      /* Ignored for compatibility with Linux' procfs. */
      break;

    case NOSUID_KEY:
      /* Ignored for compatibility with Linux' procfs. */
      break;

    case ARGP_KEY_ARG:
      if (!strcmp (arg, "none") || !strcmp (arg,"proc"))
        /* Ignored for compatibility with Linux' procfs. */
        break;
      return ARGP_ERR_UNKNOWN;

    default:
      return ARGP_ERR_UNKNOWN;
  }

  return 0;
}

struct argp_option common_options[] = {
#define STR(X)	XSTR (X)
#define XSTR(X)	#X
  { "clk-tck", 'h', "HZ", 0,
      "Unit used for the values expressed in system clock ticks "
      "(default: " STR (OPT_CLK_TCK) ")" },
  { "stat-mode", 's', "MODE", 0,
      "The [pid]/stat file publishes information which on Hurd is only "
      "available to the process owner.  "
      "You can use this option to override its mode to be more permissive "
      "for compatibility purposes.  "
      "(default: " STR (OPT_STAT_MODE) ")" },
  { "fake-self", 'S', "PID", OPTION_ARG_OPTIONAL,
      "Provide a fake \"self\" symlink to the given PID, for compatibility "
      "purposes.  If PID is omitted, \"self\" will point to init.  "
      "(default: no self link)" },
  { "kernel-process", 'k', "PID", 0,
      "Process identifier for the kernel, used to retrieve its command "
      "line, as well as the global up and idle times. "
      "(default: " STR (OPT_KERNEL_PID) ")" },
  { "compatible", 'c', NULL, 0,
      "Try to be compatible with the Linux procps utilities.  "
      "Currently equivalent to -h 100 -s 0444 -S 1." },
  { "anonymous-owner", 'a', "USER", 0,
      "Make USER the owner of files related to processes without one.  "
      "Be aware that USER will be granted access to the environment and "
      "other sensitive information about the processes in question.  "
      "(default: use uid " STR (OPT_ANON_OWNER) ")" },
  { "nodev", NODEV_KEY, NULL, 0,
      "Ignored for compatibility with Linux' procfs." },
  { "noexec", NOEXEC_KEY, NULL, 0,
      "Ignored for compatibility with Linux' procfs." },
  { "nosuid", NOSUID_KEY, NULL, 0,
      "Ignored for compatibility with Linux' procfs." },
  {}
#undef XSTR
#undef STR
};

struct argp argp = {
  .options = common_options,
  .parser = argp_parser,
  .doc = "A virtual filesystem emulating the Linux procfs.",
  .children = (struct argp_child []) {
    { &netfs_std_startup_argp, },
    {}
  },
};

static error_t
runtime_argp_parser (int key, char *arg, struct argp_state *state)
{
  switch (key)
  {
    case 'u':
      /* do nothing */
      break;

    default:
      return ARGP_ERR_UNKNOWN;
  }

  return 0;
}

struct argp runtime_argp = {
  .options = (struct argp_option []) {
    { "update", 'u', NULL, 0, "remount; for procfs this does nothing" },
    {},
  },
  .parser = runtime_argp_parser,
};

struct argp netfs_runtime_argp_ = {
  .options = common_options,
  .parser = argp_parser,
  .doc = "A virtual filesystem emulating the Linux procfs.",
  .children = (struct argp_child []) {
    { &runtime_argp, },
    { &netfs_std_runtime_argp, },
    {}
  },
};

/* Used by netfs_set_options to handle runtime option parsing.  */
struct argp *netfs_runtime_argp = &netfs_runtime_argp_;

/* Return an argz string describing the current options.  Fill *ARGZ
   with a pointer to newly malloced storage holding the list and *LEN
   to the length of that storage.  */
error_t
netfs_append_args (char **argz, size_t *argz_len)
{
  char buf[80];
  error_t err = 0;

#define FOPT(opt, default, fmt, args...)             \
  do { \
    if (! err && opt != default) \
      { \
	snprintf (buf, sizeof buf, fmt, ## args); \
	err = argz_add (argz, argz_len, buf); \
      } \
  } while (0)

  FOPT (opt_clk_tck, OPT_CLK_TCK,
        "--clk-tck=%d", opt_clk_tck);

  FOPT (opt_stat_mode, OPT_STAT_MODE,
        "--stat-mode=%o", opt_stat_mode);

  FOPT (opt_fake_self, OPT_FAKE_SELF,
        "--fake-self=%d", opt_fake_self);

  FOPT (opt_anon_owner, OPT_ANON_OWNER,
        "--anonymous-owner=%d", opt_anon_owner);

  FOPT (opt_kernel_pid, OPT_KERNEL_PID,
        "--kernel-process=%d", opt_kernel_pid);

#undef FOPT

  if (! err)
    err = netfs_append_std_options (argz, argz_len);

  return err;
}

/* The user may define this function.  The function must set source to
   the source of CRED. The function may return an EOPNOTSUPP to
   indicate that the concept of a source device is not applicable. The
   default function always returns EOPNOTSUPP. */
error_t netfs_get_source (struct protid *cred, char *source, size_t source_len)
{
  if (! cred)
    return EOPNOTSUPP;
  snprintf (source, source_len, "proc");
  return 0;
}

error_t
root_make_node (struct ps_context *pc, struct node **np)
{
  struct node *root_dirs[] = {
    proclist_make_node (pc),
    rootdir_make_node (pc),
  };

  *np = dircat_make_node (root_dirs, sizeof root_dirs / sizeof root_dirs[0]);
  if (! *np)
    return ENOMEM;

  /* Since this one is not created through proc_lookup(), we have to affect an
     inode number to it.  */
  (*np)->nn_stat.st_ino = * (uint32_t *) "PROC";

  return 0;
}

int main (int argc, char **argv)
{
  struct ps_context *pc;
  mach_port_t bootstrap;
  error_t err;

  opt_clk_tck = OPT_CLK_TCK;
  opt_stat_mode = OPT_STAT_MODE;
  opt_fake_self = OPT_FAKE_SELF;
  opt_kernel_pid = OPT_KERNEL_PID;
  opt_anon_owner = OPT_ANON_OWNER;
  err = argp_parse (&argp, argc, argv, 0, 0, 0);
  if (err)
    error (1, err, "Could not parse command line");

  err = ps_context_create (getproc (), &pc);
  if (err)
    error (1, err, "Could not create libps context");

  task_get_bootstrap_port (mach_task_self (), &bootstrap);
  if (bootstrap == MACH_PORT_NULL)
    error (1, 0, "Must be started as a translator");

  netfs_init ();
  err = root_make_node (pc, &netfs_root_node);
  if (err)
    error (1, err, "Could not create the root node");

  netfs_startup (bootstrap, 0);
  netfs_server_loop ();

  assert (0 /* netfs_server_loop returned after all */);
}