/mandos/trunk

To get this branch, use:
bzr branch http://bzr.recompile.se/loggerhead/mandos/trunk

« back to all changes in this revision

Viewing changes to plugins.d/password-prompt.c

  • Committer: Teddy Hogeborn
  • Date: 2011-02-27 18:57:58 UTC
  • Revision ID: teddy@fukt.bsnet.se-20110227185758-vie4xhfaevhpqtr6
* plugins.d/password-prompt.c (conflict_detection): Check for both
                                                    "plymouth" and
                                                    "plymouthd".

Show diffs side-by-side

added added

removed removed

Lines of Context:
plugins.d/password-prompt.c
35
35
                                   SIGQUIT, SIGHUP, SIGTERM,
36
36
                                   raise() */
37
37
#include <stddef.h>             /* NULL, size_t, ssize_t */
38
 
#include <sys/types.h>          /* ssize_t, struct dirent, pid_t, ssize_t */
 
38
#include <sys/types.h>          /* ssize_t, struct dirent, pid_t,
 
39
                                   ssize_t, open() */
39
40
#include <stdlib.h>             /* EXIT_SUCCESS, EXIT_FAILURE,
40
41
                                   getenv(), free() */
41
42
#include <dirent.h>             /* scandir(), alphasort() */
49
50
#include <iso646.h>             /* or, not */
50
51
#include <stdbool.h>            /* bool, false, true */
51
52
#include <inttypes.h>           /* strtoumax() */
52
 
#include <sys/stat.h>           /* struct stat, lstat() */
 
53
#include <sys/stat.h>           /* struct stat, lstat(), open() */
53
54
#include <string.h>             /* strlen, rindex, memcmp */
54
55
#include <argp.h>               /* struct argp_option, struct
55
56
                                   argp_state, struct argp,
58
59
                                   ARGP_ERR_UNKNOWN */
59
60
#include <sysexits.h>           /* EX_SOFTWARE, EX_OSERR,
60
61
                                   EX_UNAVAILABLE, EX_IOERR, EX_OK */
 
62
#include <fcntl.h>              /* open() */
61
63
 
62
64
volatile sig_atomic_t quit_now = 0;
63
65
int signal_received;
65
67
const char *argp_program_version = "password-prompt " VERSION;
66
68
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
67
69
 
68
 
/* Needed for conflic resolution */
69
 
const char plymouthd_path[] = "/sbin/plymouth";
 
70
/* Needed for conflict resolution */
 
71
const char plymouth_name[] = "plymouthd";
 
72
const char plymouth_alt_name[] = "plymouthd";
70
73
 
71
74
 
72
75
static void termination_handler(int signum){
79
82
 
80
83
bool conflict_detection(void){
81
84
 
82
 
  /* plymouth conflicts with password-promt since both want to control the
83
 
     associated terminal. Password-prompt exit since plymouth perferms the same
84
 
     functionallity.
 
85
  /* plymouth conflicts with password-prompt since both want to read
 
86
     from the terminal.  Password-prompt will exit if it detects
 
87
     plymouth since plymouth performs the same functionality.
85
88
   */
86
89
  int is_plymouth(const struct dirent *proc_entry){
87
90
    int ret;
 
91
    int cl_fd;
88
92
    {
89
93
      uintmax_t maxvalue;
90
94
      char *tmp;
96
100
        return 0;
97
101
      }
98
102
    }
99
 
    char exe_target[sizeof(plymouthd_path)];
100
 
    char *exe_link;
101
 
    ret = asprintf(&exe_link, "/proc/%s/exe", proc_entry->d_name);
 
103
    
 
104
    char *cmdline_filename;
 
105
    ret = asprintf(&cmdline_filename, "/proc/%s/cmdline", proc_entry->d_name);
102
106
    if(ret == -1){
103
107
      error(0, errno, "asprintf");
104
108
      return 0;
105
109
    }
106
 
  
107
 
    struct stat exe_stat;
108
 
    ret = lstat(exe_link, &exe_stat);
109
 
    if(ret == -1){
110
 
      free(exe_link);
111
 
      if(errno != ENOENT){
112
 
        error(0, errno, "lstat");
 
110
    
 
111
    /* Open /proc/<pid>/cmdline  */
 
112
    cl_fd = open(cmdline_filename, O_RDONLY);
 
113
    free(cmdline_filename);
 
114
    if(cl_fd == -1){
 
115
      error(0, errno, "open");
 
116
      return 0;
 
117
    }
 
118
    
 
119
    char *cmdline = NULL;
 
120
    {
 
121
      size_t cmdline_len = 0;
 
122
      size_t cmdline_allocated = 0;
 
123
      char *tmp;
 
124
      const size_t blocksize = 1024;
 
125
      ssize_t sret;
 
126
      do {
 
127
        /* Allocate more space? */
 
128
        if(cmdline_len + blocksize + 1 > cmdline_allocated){
 
129
          tmp = realloc(cmdline, cmdline_allocated + blocksize + 1);
 
130
          if(tmp == NULL){
 
131
            error(0, errno, "realloc");
 
132
            free(cmdline);
 
133
            close(cl_fd);
 
134
            return 0;
 
135
          }
 
136
          cmdline = tmp;
 
137
          cmdline_allocated += blocksize;
 
138
        }
 
139
        
 
140
        /* Read data */
 
141
        sret = read(cl_fd, cmdline + cmdline_len,
 
142
                    cmdline_allocated - cmdline_len);
 
143
        if(sret == -1){
 
144
          error(0, errno, "read");
 
145
          free(cmdline);
 
146
          close(cl_fd);
 
147
          return 0;
 
148
        }
 
149
        cmdline_len += (size_t)sret;
 
150
      } while(sret != 0);
 
151
      ret = close(cl_fd);
 
152
      if(ret == -1){
 
153
        error(0, errno, "close");
 
154
        free(cmdline);
 
155
        return 0;
113
156
      }
114
 
      return 0;
115
 
    }
116
 
  
117
 
    if(not S_ISLNK(exe_stat.st_mode)
118
 
       or exe_stat.st_uid != 0
119
 
       or exe_stat.st_gid != 0){
120
 
      free(exe_link);
121
 
      return 0;
122
 
    }
123
 
  
124
 
    ssize_t sret = readlink(exe_link, exe_target, sizeof(exe_target));
125
 
    free(exe_link);
126
 
    if((sret != (ssize_t)sizeof(plymouthd_path)-1) or
127
 
       (memcmp(plymouthd_path, exe_target,
128
 
               sizeof(plymouthd_path)-1) != 0)){
129
 
      return 0;
130
 
    }
 
157
      cmdline[cmdline_len] = '\0'; /* Make sure it is terminated */
 
158
    }
 
159
    /* we now have cmdline */
 
160
    
 
161
    /* get basename */
 
162
    char *cmdline_base = strrchr(cmdline, '/');
 
163
    if(cmdline_base != NULL){
 
164
      cmdline_base += 1;                /* skip the slash */
 
165
    } else {
 
166
      cmdline_base = cmdline;
 
167
    }
 
168
    
 
169
    if((strcmp(cmdline_base, plymouth_name) != 0)
 
170
       and (strcmp(cmdline_base, plymouth_alt_name) != 0)){
 
171
      free(cmdline);
 
172
      return 0;
 
173
    }
 
174
    free(cmdline);
131
175
    return 1;
132
176
  }
133
177
 
137
181
  if (ret == -1){
138
182
    error(1, errno, "scandir");
139
183
  }
140
 
  if (ret < 0){
141
 
    return 1;
142
 
  } else {
143
 
    return 0;
144
 
  }
 
184
  return ret > 0;
145
185
}
146
186
 
147
187