user_list.c

   1 /*
   2  * Copyright (C) 2006-2009 Andre Noll <maan@systemlinux.org>
   3  *
   4  * Licensed under the GPL v2. For licencing details see COPYING.
   5  */
   6
   7 /** \file user_list.c User handling for para_server. */
   8
   9 #include <regex.h>
  10 #include <sys/types.h>
  11 #include <dirent.h>
  12 #include <openssl/rc4.h>
  13
  14 #include "para.h"
  15 #include "error.h"
  16 #include "crypt.h"
  17 #include "fd.h"
  18 #include "string.h"
  19 #include "list.h"
  20 #include "user_list.h"
  21
  22 static struct list_head user_list;
  23
  24 /*
  25  * Fill the list of users known to para_server.
  26  *
  27  * Populates a linked list of all users in \a user_list_file.  Returns on
  28  * success, calls exit() on errors.
  29  */
  30 static void populate_user_list(char *user_list_file)
  31 {
  32         int ret = -E_USERLIST;
  33         FILE *file_ptr = fopen(user_list_file, "r");
  34
  35         if (!file_ptr)
  36                 goto err;
  37         for (;;) {
  38                 int num;
  39                 char line[255];
  40                 /* keyword, name, key, perms */
  41                 char w[255], n[255], k[255], p[255], tmp[4][255];
  42                 struct user *u;
  43                 RSA *rsa;
  44
  45                 ret = para_fgets(line, MAXLINE, file_ptr);
  46                 if (ret <= 0)
  47                         break;
  48                 if (sscanf(line,"%200s %200s %200s %200s", w, n, k, p) < 3)
  49                         continue;
  50                 if (strcmp(w, "user"))
  51                         continue;
  52                 PARA_DEBUG_LOG("found entry for user %s\n", n);
  53                 ret = get_rsa_key(k, &rsa, LOAD_PUBLIC_KEY);
  54                 if (ret < 0) {
  55                         PARA_NOTICE_LOG("skipping entry for user %s: %s\n", n,
  56                                 para_strerror(-ret));
  57                         continue;
  58                 }
  59                 if (ret < CHALLENGE_SIZE + 2 * CHALLENGE_SIZE + 41) {
  60                         PARA_WARNING_LOG("rsa key for %s too small\n", n);
  61                         rsa_free(rsa);
  62                         continue;
  63                 }
  64                 u = para_malloc(sizeof(*u));
  65                 u->name = para_strdup(n);
  66                 u->rsa = rsa;
  67                 u->perms = 0;
  68                 num = sscanf(p, "%200[A-Z_],%200[A-Z_],%200[A-Z_],%200[A-Z_]",
  69                         tmp[0], tmp[1], tmp[2], tmp[3]);
  70                 PARA_DEBUG_LOG("found %i perm entries\n", num);
  71                 while (num > 0) {
  72                         num--;
  73                         if (!strcmp(tmp[num], "VSS_READ"))
  74                                 u->perms |= VSS_READ;
  75                         else if (!strcmp(tmp[num], "VSS_WRITE"))
  76                                 u->perms |= VSS_WRITE;
  77                         else if (!strcmp(tmp[num], "AFS_READ"))
  78                                 u->perms |= AFS_READ;
  79                         else if (!strcmp(tmp[num], "AFS_WRITE"))
  80                                 u->perms |= AFS_WRITE;
  81                         else /* unknown permission */
  82                                 PARA_WARNING_LOG("ignoring unknown permission: %s\n",
  83                                         tmp[num]);
  84                 }
  85                 para_list_add(&u->node, &user_list);
  86         }
  87         fclose(file_ptr);
  88         if (ret >= 0)
  89                 return;
  90 err:
  91         PARA_EMERG_LOG("%s\n", para_strerror(-ret));
  92         exit(EXIT_FAILURE);
  93 }
  94
  95 /**
  96  * Initialize the list of users allowed to connect to to para_server.
  97  *
  98  * \param user_list_file The file containing access information.
  99  *
 100  * If this function is called for the second time, the contents of the
 101  * previous call are discarded, i.e. the user list is reloaded.
 102  */
 103 void init_user_list(char *user_list_file)
 104 {
 105         struct user *u, *tmp;
 106         static int initialized;
 107
 108         if (initialized) {
 109                 list_for_each_entry_safe(u, tmp, &user_list, node) {
 110                         list_del(&u->node);
 111                         free(u->name);
 112                         rsa_free(u->rsa);
 113                         free(u);
 114                 }
 115         } else
 116                 INIT_LIST_HEAD(&user_list);
 117         initialized = 1;
 118         populate_user_list(user_list_file);
 119 }
 120
 121 /**
 122  * Lookup a user in the user list.
 123  *
 124  * \param name The name of the user.
 125  *
 126  * \return A pointer to the corresponding user struct if the user was found, \p
 127  * NULL otherwise.
 128  */
 129 struct user *lookup_user(const char *name)
 130 {
 131         struct user *u;
 132         list_for_each_entry(u, &user_list, node) {
 133                 if (strcmp(u->name, name))
 134                         continue;
 135                 return u;
 136         }
 137         return NULL;
 138 }