proc_utils.c

   1 /*
   2  * Copyright (C) 2010 gonzoj
   3  *
   4  * This program is free software: you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation, either version 3 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 #include <errno.h>
  19 #include <limits.h>
  20 #include <stdio.h>
  21 #include <stdlib.h>
  22 #include <string.h>
  23 #include <unistd.h>
  24
  25 #include "proc_utils.h"
  26
  27 #define PID_MAX 5
  28
  29 char *
  30 read_line(FILE *file)
  31 {
  32   static char *line = NULL;
  33
  34   if (line)
  35     {
  36       free(line);
  37       line = NULL;
  38     }
  39
  40   int i = 0;
  41   while (!feof(file))
  42     {
  43       if (i % 512 == 0)
  44         {
  45           line = (char *) realloc(line, i + 512);
  46           if (line == NULL)
  47             {
  48               printf("err: %s\n", strerror(errno));
  49               return NULL;
  50             }
  51         }
  52
  53       char chr = fgetc(file);
  54       if (chr == EOF)
  55         {
  56           break;
  57         }
  58       if (chr == '\n')
  59         {
  60           line[i] = '\0';
  61           break;
  62         }
  63       line[i++] = chr;
  64     }
  65
  66   return line;
  67 }
  68
  69 int
  70 proc_get_object_base(const char *object, vaddr_t *base)
  71 {
  72   char *path =
  73       (char *) malloc(strlen("/proc/") + PID_MAX + strlen("/maps") + 1);
  74   if (path == NULL)
  75     {
  76       printf("err: %s\n", strerror(errno));
  77       return 0;
  78     }
  79   sprintf(path, "/proc/%u/maps", pid);
  80   FILE *maps = fopen(path, "r");
  81   if (maps == NULL)
  82     {
  83       printf("err: %s\n", strerror(errno));
  84       free(path);
  85       return 0;
  86     }
  87
  88   int found = 0;
  89   char *line;
  90   while ((line = read_line(maps)))
  91     {
  92       if (strstr(line, object))
  93         {
  94           char *tmp = strchr(line, '-');
  95           if (tmp)
  96             {
  97               *tmp = '\0';
  98               sscanf(line, "%lx", (long unsigned *) base);
  99               found = 1;
 100               break;
 101             }
 102         }
 103     }
 104
 105   fclose(maps);
 106   free(path);
 107
 108   return found;
 109 }
 110
 111 char *
 112 proc_get_object_path(vaddr_t object_base)
 113 {
 114   static char *object_path = NULL;
 115
 116   if (object_path)
 117     {
 118       free(object_path);
 119       object_path = NULL;
 120     }
 121
 122   char *path =
 123       (char *) malloc(strlen("/proc/") + PID_MAX + strlen("/maps") + 1);
 124   if (path == NULL)
 125     {
 126       printf("err: %s\n", strerror(errno));
 127       return NULL;
 128     }
 129   sprintf(path, "/proc/%u/maps", pid);
 130   FILE *maps = fopen(path, "r");
 131   if (maps == NULL)
 132     {
 133       printf("err: %s\n", strerror(errno));
 134       free(path);
 135       return NULL;
 136     }
 137
 138   char *line;
 139   while ((line = read_line(maps)))
 140     {
 141       char *tmp = strchr(line, '-');
 142       if (tmp)
 143         {
 144           *tmp++ = '\0';
 145           vaddr_t base;
 146           sscanf(line, "%lx", (long unsigned *) &base);
 147           if (base == object_base)
 148             {
 149               object_path = (char *) malloc(strlen(tmp));
 150               strcpy(object_path, strchr(tmp, '/'));
 151               break;
 152             }
 153         }
 154     }
 155
 156   fclose(maps);
 157   free(path);
 158
 159   return object_path;
 160 }
 161
 162 char *
 163 proc_get_executable()
 164 {
 165   static char *executable;
 166
 167   if (executable)
 168     {
 169       free(executable);
 170       executable = NULL;
 171     }
 172
 173   char *path = (char *) malloc(strlen("/proc/") + PID_MAX + strlen("/exe") + 1);
 174   if (path == NULL)
 175     {
 176       printf("err: %s\n", strerror(errno));
 177       return NULL;
 178     }
 179   sprintf(path, "/proc/%u/exe", pid);
 180   executable = (char *) malloc(PATH_MAX); // let's hope that one is defined :(
 181   if (readlink(path, executable, PATH_MAX) == -1)
 182     {
 183       printf("err: %s\n", strerror(errno));
 184       free(path);
 185       return NULL;
 186     }
 187
 188   free(path);
 189
 190   return executable;
 191 }
 192
 193 int
 194 proc_iterate_addrspace(vaddr_t *base)
 195 {
 196   static FILE *maps = NULL;
 197   if (maps == NULL)
 198     {
 199       char *path = (char *) malloc(strlen("/proc/") + PID_MAX + strlen("/maps")
 200           + 1);
 201       if (path == NULL)
 202         {
 203           printf("err: %s\n", strerror(errno));
 204           return 0;
 205         }
 206       sprintf(path, "/proc/%u/maps", pid);
 207       maps = fopen(path, "r");
 208       if (maps == NULL)
 209         {
 210           printf("err: %s\n", strerror(errno));
 211           free(path);
 212           return 0;
 213         }
 214       free(path);
 215     }
 216
 217   char *line;
 218   while ((line = read_line(maps)))
 219     {
 220       char *tmp = strchr(line, '-');
 221       if (tmp)
 222         {
 223           *tmp++ = '\0';
 224           strtok(tmp, " ");
 225           tmp = strtok(NULL, " ");
 226           if (strchr(tmp, 'r'))
 227             {
 228               strtok(NULL, " ");
 229               strtok(NULL, " ");
 230               strtok(NULL, " ");
 231               tmp = strtok(NULL, " ");
 232               if (tmp)
 233                 {
 234                   if (strstr(tmp, "/dev") == tmp)
 235                     {
 236                       continue;
 237                     }
 238                 }
 239               sscanf(line, "%lx", (long unsigned *) base);
 240               return 1;
 241             }
 242           else
 243             {
 244               continue;
 245             }
 246         }
 247     }
 248   fclose(maps);
 249   maps = NULL;
 250
 251   return 0;
 252 }