only select for write, if it was not possible before
[oweals/gnunet.git] / src / vpn / gnunet-daemon-vpn.c
1 /*
2      This file is part of GNUnet.
3      (C) 2010 Christian Grothoff
4
5      GNUnet is free software; you can redistribute it and/or modify
6      it under the terms of the GNU General Public License as published
7      by the Free Software Foundation; either version 3, or (at your
8      option) any later version.
9
10      GNUnet is distributed in the hope that it will be useful, but
11      WITHOUT ANY WARRANTY; without even the implied warranty of
12      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13      General Public License for more details.
14
15      You should have received a copy of the GNU General Public License
16      along with GNUnet; see the file COPYING.  If not, write to the
17      Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18      Boston, MA 02111-1307, USA.
19 */
20
21 /**
22  * @file vpn/gnunet-daemon-vpn.c
23  * @brief 
24  * @author Philipp Tölke
25  */
26 #include "platform.h"
27 #include "gnunet_getopt_lib.h"
28 #include "gnunet_program_lib.h"
29 #include "gnunet_os_lib.h"
30 #include "gnunet-vpn-helper-p.h"
31 #include "gnunet-vpn-packet.h"
32 #include "gnunet-vpn-pretty-print.h"
33 /* #include "gnunet_template_service.h" */
34
35 /**
36  * Final status code.
37  */
38 static int ret;
39
40 struct vpn_cls {
41         struct GNUNET_DISK_PipeHandle* helper_in;
42         struct GNUNET_DISK_PipeHandle* helper_out;
43         const struct GNUNET_DISK_FileHandle* fh_from_helper;
44
45         struct GNUNET_SCHEDULER_Handle *sched;
46
47         pid_t helper_pid;
48 };
49
50 static void cleanup(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tskctx) {
51         struct vpn_cls* mycls = (struct vpn_cls*) cls;
52         if (tskctx->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN) {
53                 PLIBC_KILL(mycls->helper_pid, SIGTERM);
54                 GNUNET_OS_process_wait(mycls->helper_pid);
55         }
56 }
57
58 static void helper_read(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tsdkctx) {
59         struct vpn_cls* mycls = (struct vpn_cls*) cls;
60         struct suid_packet_header hdr = { .size = 0 };
61
62         int r = 0;
63
64         if (tsdkctx->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN)
65                 return;
66
67         while (r < sizeof(struct suid_packet_header)) {
68                 int t = GNUNET_DISK_file_read(mycls->fh_from_helper, &hdr, sizeof(struct suid_packet_header));
69                 if (t< 0) {
70                         fprintf(stderr, "Read error for header: %m\n");
71                         return;
72                 }
73                 r += t;
74         }
75
76         struct suid_packet *pkt = (struct suid_packet*) GNUNET_malloc(ntohl(hdr.size));
77
78         if (memcpy(pkt, &hdr, sizeof(struct suid_packet_header)) < 0) {
79                 fprintf(stderr, "Memcpy: %m\n");
80                 return;
81         }
82
83         while (r < ntohl(pkt->hdr.size)) {
84                 int t = GNUNET_DISK_file_read(mycls->fh_from_helper, (unsigned char*)pkt + r, ntohl(pkt->hdr.size) - r);
85                 if (t< 0) {
86                         fprintf(stderr, "Read error for data: %m\n");
87                         return;
88                 }
89                 r += t;
90         }
91
92         struct ip6_pkt *pkt6 = (struct ip6_pkt*) pkt;
93         struct ip6_tcp *pkt6_tcp;
94         struct ip6_udp *pkt6_udp;
95
96         pkt_printf(pkt6);
97         switch(pkt6->ip6_hdr.nxthdr) {
98                 case 0x06:
99                         pkt6_tcp = (struct ip6_tcp*)pkt6;
100                         pkt_printf_ip6tcp(pkt6_tcp);
101                         break;
102                 case 0x11:
103                         pkt6_udp = (struct ip6_udp*)pkt6;
104                         pkt_printf_ip6udp(pkt6_udp);
105                         if (ntohs(pkt6_udp->udp_hdr.dpt) == 53) {
106                                 pkt_printf_ip6dns((struct ip6_udp_dns*)pkt6_udp);
107                         }
108                         break;
109         }
110
111         GNUNET_free(pkt);
112
113         GNUNET_SCHEDULER_add_read_file (mycls->sched, GNUNET_TIME_UNIT_FOREVER_REL, mycls->fh_from_helper, &helper_read, mycls);
114 }
115
116 /**
117  * Main function that will be run by the scheduler.
118  *
119  * @param cls closure
120  * @param sched the scheduler to use
121  * @param args remaining command-line arguments
122  * @param cfgfile name of the configuration file used (for saving, can be NULL!)
123  * @param cfg configuration
124  */
125 static void
126 run (void *cls,
127                 struct GNUNET_SCHEDULER_Handle *sched,
128                 char *const *args,
129                 const char *cfgfile,
130                 const struct GNUNET_CONFIGURATION_Handle *cfg) {
131
132         struct vpn_cls* mycls = (struct vpn_cls*) cls;
133
134         mycls->sched = sched;
135
136         GNUNET_SCHEDULER_add_delayed(sched, GNUNET_TIME_UNIT_FOREVER_REL, &cleanup, cls);
137
138         mycls->helper_in = GNUNET_DISK_pipe(1);
139         mycls->helper_out = GNUNET_DISK_pipe(1);
140
141         mycls->helper_pid = GNUNET_OS_start_process(mycls->helper_in, mycls->helper_out, "gnunet-vpn-helper", "gnunet-vpn-helper", NULL);
142
143         mycls->fh_from_helper = GNUNET_DISK_pipe_handle (mycls->helper_out, GNUNET_DISK_PIPE_END_READ);
144         
145         GNUNET_SCHEDULER_add_read_file (sched, GNUNET_TIME_UNIT_FOREVER_REL, mycls->fh_from_helper, &helper_read, mycls);
146 }
147
148
149 /**
150  * The main function to obtain template from gnunetd.
151  *
152  * @param argc number of arguments from the command line
153  * @param argv command line arguments
154  * @return 0 ok, 1 on error
155  */
156 int
157 main (int argc, char *const *argv)
158 {
159   static const struct GNUNET_GETOPT_CommandLineOption options[] = {
160     GNUNET_GETOPT_OPTION_END
161   };
162
163   struct vpn_cls* cls = (struct vpn_cls*)malloc(sizeof(struct vpn_cls));
164
165   return (GNUNET_OK ==
166           GNUNET_PROGRAM_run (argc,
167                               argv,
168                               "gnunet-daemon-vpn",
169                               gettext_noop ("help text"),
170                               options, &run, cls)) ? ret : 1;
171 }
172
173 /* end of gnunet-daemon-vpn.c */