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