/mandos/trunk

To get this branch, use:
bzr branch http://bzr.recompile.se/loggerhead/mandos/trunk
237.1.2 by Teddy Hogeborn
Further steps towards a D-Bus server interface, plus minor syntax
1
/*  -*- coding: utf-8 -*- */
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/*
261 by Teddy Hogeborn
* plugins.d/askpass-fifo.c: Fix name in header.
3
 * Askpass-FIFO - Read a password from a FIFO and output it
237.1.2 by Teddy Hogeborn
Further steps towards a D-Bus server interface, plus minor syntax
4
 * 
979 by Teddy Hogeborn
Update copyright year to 2019
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 * Copyright © 2008-2019 Teddy Hogeborn
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 * Copyright © 2008-2019 Björn Påhlsson
237.1.2 by Teddy Hogeborn
Further steps towards a D-Bus server interface, plus minor syntax
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 * 
907 by Teddy Hogeborn
Alter copyright notices slightly. Actual license is unchanged!
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 * This file is part of Mandos.
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 * 
10
 * Mandos is free software: you can redistribute it and/or modify it
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 * under the terms of the GNU General Public License as published by
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 * the Free Software Foundation, either version 3 of the License, or
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 * (at your option) any later version.
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 * 
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 * Mandos is distributed in the hope that it will be useful, but
237.1.2 by Teddy Hogeborn
Further steps towards a D-Bus server interface, plus minor syntax
16
 * WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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 * General Public License for more details.
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 * 
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 * You should have received a copy of the GNU General Public License
907 by Teddy Hogeborn
Alter copyright notices slightly. Actual license is unchanged!
21
 * along with Mandos.  If not, see <http://www.gnu.org/licenses/>.
237.1.2 by Teddy Hogeborn
Further steps towards a D-Bus server interface, plus minor syntax
22
 * 
505.1.2 by Teddy Hogeborn
Change "fukt.bsnet.se" to "recompile.se" throughout.
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 * Contact the authors at <mandos@recompile.se>.
237.1.2 by Teddy Hogeborn
Further steps towards a D-Bus server interface, plus minor syntax
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 */
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1233 by Teddy Hogeborn
Fix #include headers
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#define _GNU_SOURCE		/* vasprintf(),
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				   program_invocation_short_name */
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#include <sys/types.h>		/* uid_t, gid_t, getuid(), getgid(),
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				   setgid(), setuid() */
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#include <unistd.h>		/* uid_t, gid_t, ssize_t, getuid(),
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				   getgid(), setgid(), setuid(),
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				   read(), close(), write(),
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				   STDOUT_FILENO */
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#include <stdarg.h>		/* va_list, va_start(), vfprintf() */
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#include <stdio.h>		/* vasprintf(), fprintf(), stderr,
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				   vfprintf() */
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#include <errno.h>		/* program_invocation_short_name,
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				   errno, EACCES, ENOTDIR, ELOOP,
390 by Teddy Hogeborn
* plugins.d/askpass-fifo.c: Do close(STDOUT_FILENO) before exiting to
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				   ENAMETOOLONG, ENOSPC, EROFS,
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				   ENOENT, EEXIST, EFAULT, EMFILE,
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				   ENFILE, ENOMEM, EBADF, EINVAL, EIO,
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				   EISDIR, EFBIG */
1233 by Teddy Hogeborn
Fix #include headers
43
#include <string.h>		/* strerror() */
24.1.155 by Björn Påhlsson
mandos server: Added debuglevel that adjust at what level information
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#include <error.h>		/* error() */
1233 by Teddy Hogeborn
Fix #include headers
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#include <stdlib.h>		/* free(), realloc(), EXIT_SUCCESS */
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#include <sys/stat.h>		/* mkfifo(), S_IRUSR, S_IWUSR */
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#include <sysexits.h>		/* EX_OSFILE, EX_OSERR,
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				   EX_UNAVAILABLE, EX_IOERR */
214 by Teddy Hogeborn
* Makefile (PLUGINS): Added "plugins.d/askpass-fifo".
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#include <fcntl.h>		/* open(), O_RDONLY */
1233 by Teddy Hogeborn
Fix #include headers
50
#include <stddef.h>		/* NULL, size_t */
24.1.174 by Björn Påhlsson
* Makefile (CFLAGS): Added "-lrt" to include real time library.
51
731 by Teddy Hogeborn
askpass-fifo: Lower privileges after opening FIFO.
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uid_t uid = 65534;
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gid_t gid = 65534;
24.1.174 by Björn Påhlsson
* Makefile (CFLAGS): Added "-lrt" to include real time library.
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55
/* Function to use when printing errors */
533 by teddy at bsnet
* plugins.d/splashy.c (error_plus): Check format string.
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__attribute__((format (gnu_printf, 3, 4)))
485 by Teddy Hogeborn
Merge from Björn.
57
void error_plus(int status, int errnum, const char *formatstring,
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		...){
24.1.174 by Björn Påhlsson
* Makefile (CFLAGS): Added "-lrt" to include real time library.
59
  va_list ap;
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  char *text;
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  int ret;
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63
  va_start(ap, formatstring);
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  ret = vasprintf(&text, formatstring, ap);
670 by Teddy Hogeborn
White space fix: change "if (" to "if(" in C code.
65
  if(ret == -1){
485 by Teddy Hogeborn
Merge from Björn.
66
    fprintf(stderr, "Mandos plugin %s: ",
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	    program_invocation_short_name);
24.1.174 by Björn Påhlsson
* Makefile (CFLAGS): Added "-lrt" to include real time library.
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    vfprintf(stderr, formatstring, ap);
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    fprintf(stderr, ": ");
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    fprintf(stderr, "%s\n", strerror(errnum));
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    error(status, errno, "vasprintf while printing error");
975 by Teddy Hogeborn
Fix warnings from -Wimplicit-fallthrough
72
    if(status){
73
      __builtin_unreachable();
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    }
24.1.174 by Björn Påhlsson
* Makefile (CFLAGS): Added "-lrt" to include real time library.
75
    return;
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  }
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  fprintf(stderr, "Mandos plugin ");
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  error(status, errnum, "%s", text);
975 by Teddy Hogeborn
Fix warnings from -Wimplicit-fallthrough
79
  if(status){
80
    __builtin_unreachable();
81
  }
24.1.174 by Björn Påhlsson
* Makefile (CFLAGS): Added "-lrt" to include real time library.
82
  free(text);
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}
214 by Teddy Hogeborn
* Makefile (PLUGINS): Added "plugins.d/askpass-fifo".
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85
int main(__attribute__((unused))int argc,
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	 __attribute__((unused))char **argv){
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  int ret = 0;
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  ssize_t sret;
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731 by Teddy Hogeborn
askpass-fifo: Lower privileges after opening FIFO.
90
  uid = getuid();
91
  gid = getgid();
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214 by Teddy Hogeborn
* Makefile (PLUGINS): Added "plugins.d/askpass-fifo".
93
  /* Create FIFO */
94
  const char passfifo[] = "/lib/cryptsetup/passfifo";
369 by Teddy Hogeborn
* init.d-mandos (Required-Start, Required-Stop): Bug fix: Added
95
  ret = mkfifo(passfifo, S_IRUSR | S_IWUSR);
390 by Teddy Hogeborn
* plugins.d/askpass-fifo.c: Do close(STDOUT_FILENO) before exiting to
96
  if(ret == -1){
97
    int e = errno;
98
    switch(e){
99
    case EACCES:
100
    case ENOTDIR:
101
    case ELOOP:
24.1.174 by Björn Påhlsson
* Makefile (CFLAGS): Added "-lrt" to include real time library.
102
      error_plus(EX_OSFILE, errno, "mkfifo");
975 by Teddy Hogeborn
Fix warnings from -Wimplicit-fallthrough
103
      __builtin_unreachable();
390 by Teddy Hogeborn
* plugins.d/askpass-fifo.c: Do close(STDOUT_FILENO) before exiting to
104
    case ENAMETOOLONG:
105
    case ENOSPC:
106
    case EROFS:
107
    default:
24.1.174 by Björn Påhlsson
* Makefile (CFLAGS): Added "-lrt" to include real time library.
108
      error_plus(EX_OSERR, errno, "mkfifo");
975 by Teddy Hogeborn
Fix warnings from -Wimplicit-fallthrough
109
      __builtin_unreachable();
390 by Teddy Hogeborn
* plugins.d/askpass-fifo.c: Do close(STDOUT_FILENO) before exiting to
110
    case ENOENT:
479 by Teddy Hogeborn
* plugins.d/askpass-fifo.c (main): Don't print message if FIFO exists.
111
      /* no "/lib/cryptsetup"? */
24.1.174 by Björn Påhlsson
* Makefile (CFLAGS): Added "-lrt" to include real time library.
112
      error_plus(EX_UNAVAILABLE, errno, "mkfifo");
975 by Teddy Hogeborn
Fix warnings from -Wimplicit-fallthrough
113
      __builtin_unreachable();
390 by Teddy Hogeborn
* plugins.d/askpass-fifo.c: Do close(STDOUT_FILENO) before exiting to
114
    case EEXIST:
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      break;			/* not an error */
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    }
214 by Teddy Hogeborn
* Makefile (PLUGINS): Added "plugins.d/askpass-fifo".
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  }
118
  
119
  /* Open FIFO */
369 by Teddy Hogeborn
* init.d-mandos (Required-Start, Required-Stop): Bug fix: Added
120
  int fifo_fd = open(passfifo, O_RDONLY);
214 by Teddy Hogeborn
* Makefile (PLUGINS): Added "plugins.d/askpass-fifo".
121
  if(fifo_fd == -1){
390 by Teddy Hogeborn
* plugins.d/askpass-fifo.c: Do close(STDOUT_FILENO) before exiting to
122
    int e = errno;
24.1.174 by Björn Påhlsson
* Makefile (CFLAGS): Added "-lrt" to include real time library.
123
    error_plus(0, errno, "open");
390 by Teddy Hogeborn
* plugins.d/askpass-fifo.c: Do close(STDOUT_FILENO) before exiting to
124
    switch(e){
125
    case EACCES:
126
    case ENOENT:
127
    case EFAULT:
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      return EX_UNAVAILABLE;
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    case ENAMETOOLONG:
130
    case EMFILE:
131
    case ENFILE:
132
    case ENOMEM:
133
    default:
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      return EX_OSERR;
135
    case ENOTDIR:
136
    case ELOOP:
137
      return EX_OSFILE;
138
    }
214 by Teddy Hogeborn
* Makefile (PLUGINS): Added "plugins.d/askpass-fifo".
139
  }
140
  
731 by Teddy Hogeborn
askpass-fifo: Lower privileges after opening FIFO.
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  /* Lower group privileges  */
142
  if(setgid(gid) == -1){
143
    error_plus(0, errno, "setgid");
144
  }
145
  
146
  /* Lower user privileges */
147
  if(setuid(uid) == -1){
148
    error_plus(0, errno, "setuid");
149
  }
150
  
214 by Teddy Hogeborn
* Makefile (PLUGINS): Added "plugins.d/askpass-fifo".
151
  /* Read from FIFO */
152
  char *buf = NULL;
153
  size_t buf_len = 0;
154
  {
155
    size_t buf_allocated = 0;
156
    const size_t blocksize = 1024;
363 by Teddy Hogeborn
* plugin-runner.c: Minor stylistic changes.
157
    do {
214 by Teddy Hogeborn
* Makefile (PLUGINS): Added "plugins.d/askpass-fifo".
158
      if(buf_len + blocksize > buf_allocated){
159
	char *tmp = realloc(buf, buf_allocated + blocksize);
160
	if(tmp == NULL){
24.1.174 by Björn Påhlsson
* Makefile (CFLAGS): Added "-lrt" to include real time library.
161
	  error_plus(0, errno, "realloc");
214 by Teddy Hogeborn
* Makefile (PLUGINS): Added "plugins.d/askpass-fifo".
162
	  free(buf);
390 by Teddy Hogeborn
* plugins.d/askpass-fifo.c: Do close(STDOUT_FILENO) before exiting to
163
	  return EX_OSERR;
214 by Teddy Hogeborn
* Makefile (PLUGINS): Added "plugins.d/askpass-fifo".
164
	}
165
	buf = tmp;
166
	buf_allocated += blocksize;
167
      }
369 by Teddy Hogeborn
* init.d-mandos (Required-Start, Required-Stop): Bug fix: Added
168
      sret = read(fifo_fd, buf + buf_len, buf_allocated - buf_len);
214 by Teddy Hogeborn
* Makefile (PLUGINS): Added "plugins.d/askpass-fifo".
169
      if(sret == -1){
390 by Teddy Hogeborn
* plugins.d/askpass-fifo.c: Do close(STDOUT_FILENO) before exiting to
170
	int e = errno;
171
	free(buf);
172
	errno = e;
24.1.174 by Björn Påhlsson
* Makefile (CFLAGS): Added "-lrt" to include real time library.
173
	error_plus(0, errno, "read");
390 by Teddy Hogeborn
* plugins.d/askpass-fifo.c: Do close(STDOUT_FILENO) before exiting to
174
	switch(e){
175
	case EBADF:
176
	case EFAULT:
177
	case EINVAL:
178
	default:
179
	  return EX_OSERR;
180
	case EIO:
181
	  return EX_IOERR;
182
	case EISDIR:
183
	  return EX_UNAVAILABLE;
184
	}
214 by Teddy Hogeborn
* Makefile (PLUGINS): Added "plugins.d/askpass-fifo".
185
      }
186
      buf_len += (size_t)sret;
363 by Teddy Hogeborn
* plugin-runner.c: Minor stylistic changes.
187
    } while(sret != 0);
214 by Teddy Hogeborn
* Makefile (PLUGINS): Added "plugins.d/askpass-fifo".
188
  }
189
  
190
  /* Close FIFO */
369 by Teddy Hogeborn
* init.d-mandos (Required-Start, Required-Stop): Bug fix: Added
191
  close(fifo_fd);
214 by Teddy Hogeborn
* Makefile (PLUGINS): Added "plugins.d/askpass-fifo".
192
  
193
  /* Print password to stdout */
194
  size_t written = 0;
195
  while(written < buf_len){
369 by Teddy Hogeborn
* init.d-mandos (Required-Start, Required-Stop): Bug fix: Added
196
    sret = write(STDOUT_FILENO, buf + written, buf_len - written);
214 by Teddy Hogeborn
* Makefile (PLUGINS): Added "plugins.d/askpass-fifo".
197
    if(sret == -1){
390 by Teddy Hogeborn
* plugins.d/askpass-fifo.c: Do close(STDOUT_FILENO) before exiting to
198
      int e = errno;
199
      free(buf);
200
      errno = e;
24.1.174 by Björn Påhlsson
* Makefile (CFLAGS): Added "-lrt" to include real time library.
201
      error_plus(0, errno, "write");
390 by Teddy Hogeborn
* plugins.d/askpass-fifo.c: Do close(STDOUT_FILENO) before exiting to
202
      switch(e){
203
      case EBADF:
204
      case EFAULT:
205
      case EINVAL:
206
	return EX_OSFILE;
207
      case EFBIG:
208
      case EIO:
209
      case ENOSPC:
210
      default:
211
	return EX_IOERR;
212
      }
214 by Teddy Hogeborn
* Makefile (PLUGINS): Added "plugins.d/askpass-fifo".
213
    }
214
    written += (size_t)sret;
215
  }
216
  free(buf);
217
  
390 by Teddy Hogeborn
* plugins.d/askpass-fifo.c: Do close(STDOUT_FILENO) before exiting to
218
  ret = close(STDOUT_FILENO);
219
  if(ret == -1){
220
    int e = errno;
24.1.174 by Björn Påhlsson
* Makefile (CFLAGS): Added "-lrt" to include real time library.
221
    error_plus(0, errno, "close");
390 by Teddy Hogeborn
* plugins.d/askpass-fifo.c: Do close(STDOUT_FILENO) before exiting to
222
    switch(e){
223
    case EBADF:
224
      return EX_OSFILE;
225
    case EIO:
226
    default:
227
      return EX_IOERR;
228
    }
229
  }
214 by Teddy Hogeborn
* Makefile (PLUGINS): Added "plugins.d/askpass-fifo".
230
  return EXIT_SUCCESS;
231
}