garden.c

   1 #include <string.h>
   2 #include <malloc.h>
   3 #include <stdlib.h>
   4 #include <sys/wait.h>
   5 #include <sys/types.h>
   6 #include "l2tpns.h"
   7 #include "plugin.h"
   8 #include "control.h"
   9
  10 int __plugin_api_version = 1;
  11 struct pluginfuncs p;
  12
  13 char *init_commands[] = {
  14         // This is for incoming connections to a gardened user
  15         "iptables -t nat -N garden_users 2>&1 >/dev/null",
  16         "iptables -t nat -F garden_users",
  17         "iptables -t nat -N garden 2>&1", /* Don't flush - init script sets this up */
  18         "iptables -t nat -A l2tpns -j garden_users",
  19         NULL
  20 };
  21
  22 char *done_commands[] = {
  23         "iptables -t nat -F garden_users 2>&1 >/dev/null",
  24         "iptables -t nat -D l2tpns -j garden_users",
  25         NULL
  26 };
  27
  28 int garden_session(sessiont *s, int flag);
  29
  30 int plugin_post_auth(struct param_post_auth *data)
  31 {
  32         // Ignore if user authentication was successful
  33         if (data->auth_allowed) return PLUGIN_RET_OK;
  34
  35         p.log(3, 0, 0, 0, "Walled Garden allowing login\n");
  36         data->auth_allowed = 1;
  37         data->s->walled_garden = 1;
  38         return PLUGIN_RET_OK;
  39 }
  40
  41 int plugin_new_session(struct param_new_session *data)
  42 {
  43         if (data->s->walled_garden) garden_session(data->s, 1);
  44         return PLUGIN_RET_OK;
  45 }
  46
  47 int plugin_kill_session(struct param_new_session *data)
  48 {
  49         if (data->s->walled_garden) garden_session(data->s, 0);
  50         return PLUGIN_RET_OK;
  51 }
  52
  53 int plugin_control(struct param_control *data)
  54 {
  55         sessiont *s;
  56         sessionidt session;
  57
  58         if (data->type != PKT_GARDEN && data->type != PKT_UNGARDEN) return PLUGIN_RET_OK;
  59         if (!data->data && data->data_length) return PLUGIN_RET_OK;
  60         session = atoi((char*)(data->data));
  61         if (!session) return PLUGIN_RET_OK; // Really?
  62         data->send_response = 1;
  63         s = p.get_session_by_id(session);
  64         if (!s || !s->ip)
  65         {
  66                 char *errormsg = "Session not connected";
  67                 *(short *)(data->response + 2) = ntohs(PKT_RESP_ERROR);
  68                 sprintf((data->response + data->response_length), "%s", errormsg);
  69                 data->response_length += strlen(errormsg) + 1;
  70
  71                 p.log(3, 0, 0, 0, "Unknown session %s\n", session);
  72                 return PLUGIN_RET_STOP;
  73         }
  74         *(short *)(data->response + 2) = ntohs(PKT_RESP_OK);
  75
  76         if (!(garden_session(s, (data->type == PKT_GARDEN))))
  77         {
  78                 char *errormsg = "User not connected";
  79                 *(short *)(data->response + 2) = ntohs(PKT_RESP_ERROR);
  80                 sprintf((data->response + data->response_length), "%s", errormsg);
  81                 data->response_length += strlen(errormsg) + 1;
  82         }
  83         return PLUGIN_RET_STOP;
  84 }
  85
  86 int garden_session(sessiont *s, int flag)
  87 {
  88         char cmd[2048];
  89
  90         if (!s) return 0;
  91         if (!s->opened) return 0;
  92
  93         /* Note that we don't handle throttling/snooping/etc here
  94          * To do that, we'd need to send an end accounting record
  95          * then a radius auth, then start accouting again.
  96          * That means that we need the password (which garden has)
  97          * and a lot of code to check that the new set of params
  98          * (routes, IP, ACLs, etc) 'matched' the old one in a
  99          * 'compatable' way. (ie user's system doesn't need to be told
 100          * of the change)
 101          *
 102          * Thats a lot of pain/code for very little gain.
 103          * If we want them redone from scratch, just sessionkill them -
 104          * a user on garden isn't going to have any open TCP
 105          * connections which are worth caring about, anyway.
 106          *
 107          * Note that the user will be rethrottled shortly by the scan
 108          * script thingy if appropriate.
 109          *
 110          * Currently, garden only directly ungardens someone if
 111          * they haven't paid their bill, and then subsequently do so
 112          * online. This isn't something which can be set up by a malicious
 113          * customer at will.
 114          */
 115         if (flag == 1)
 116         {
 117                 // Gardened User
 118                 p.log(2, 0, 0, s->tunnel, "Trap user %s (%s) in walled garden\n", s->user, p.inet_toa(ntohl(s->ip)));
 119                 snprintf(cmd, 2048, "iptables -t nat -A garden_users -s %s -j garden", p.inet_toa(ntohl(s->ip)));
 120                 p.log(3, 0, 0, s->tunnel, "%s\n", cmd);
 121                 system(cmd);
 122                 s->walled_garden = 1;
 123         }
 124         else
 125         {
 126                 sessionidt other;
 127                 int count = 40;
 128
 129                 // Normal User
 130                 p.log(2, 0, 0, s->tunnel, "Release user %s (%s) from walled garden\n", s->user, p.inet_toa(ntohl(s->ip)));
 131                 // Kick off any duplicate usernames
 132                 // but make sure not to kick off ourself
 133                 if (s->ip && !s->die && (other = p.get_session_by_username(s->user)) && s != p.get_session_by_id(other)) {
 134                         p.sessionkill(other, "Duplicate session when user un-gardened");
 135                 }
 136                 /* Clean up counters */
 137                 s->cin = s->cout = 0;
 138                 s->pin = s->pout = 0;
 139
 140                 snprintf(cmd, 2048, "iptables -t nat -D garden_users -s %s -j garden", p.inet_toa(ntohl(s->ip)));
 141                 p.log(3, 0, 0, s->tunnel, "%s\n", cmd);
 142                 while (--count)
 143                 {
 144                         int status = system(cmd);
 145                         if (WEXITSTATUS(status) != 0) break;
 146                 }
 147
 148                 s->walled_garden = 0;
 149
 150                 if (!s->die) {
 151                         /* OK, we're up! */
 152                         u16 r = p.radiusnew(p.get_id_by_session(s));
 153                         p.radiussend(r, RADIUSSTART);
 154                 }
 155         }
 156         s->walled_garden = flag;
 157         return 1;
 158 }
 159
 160 int plugin_init(struct pluginfuncs *funcs)
 161 {
 162         int i;
 163
 164         if (!funcs) return 0;
 165         memcpy(&p, funcs, sizeof(p));
 166
 167         for (i = 0; init_commands[i] && *init_commands[i]; i++)
 168         {
 169                 p.log(3, 0, 0, 0, "Running %s\n", init_commands[i]);
 170                 system(init_commands[i]);
 171         }
 172
 173         return 1;
 174 }
 175
 176 void plugin_done()
 177 {
 178         int i;
 179         for (i = 0; done_commands[i] && *done_commands[i]; i++)
 180         {
 181                 p.log(3, 0, 0, 0, "Running %s\n", done_commands[i]);
 182                 system(done_commands[i]);
 183         }
 184 }
 185