Begin implementing the gnunet-vpn-helper

4 files changed, 116 insertions, 64 deletions

diff --git a/src/vpn/Makefile.am b/src/vpn/Makefile.am
index 1fff59309..480d58145 100644
--- a/src/vpn/Makefile.am
+++ b/src/vpn/Makefile.am
@@ -23,12 +23,17 @@ bin_PROGRAMS = \
 
 
 gnunet_vpn_helper_SOURCES = \
- debug.c  debug.h \
- packet.h packet.c \
- pretty-print.c  pretty-print.h \
- tcp.c  tcp.h \
- test.c \
- tun.c  tun.h
+ gnunet-vpn-helper.c \
+ gnunet-vpn-helper-p.h \
+ tun.h tun.c
+
+# debug.c  debug.h \
+# packet.h packet.c \
+# pretty-print.c  pretty-print.h \
+# tcp.c  tcp.h \
+# test.c \
+# tun.c  tun.h \
+# udp.c udp.h
 
 gnunet_daemon_vpn_SOURCES = \
  gnunet-daemon-vpn.c
diff --git a/src/vpn/gnunet-vpn-helper-p.h b/src/vpn/gnunet-vpn-helper-p.h
new file mode 100644
index 000000000..d2fac593a
--- /dev/null
+++ b/src/vpn/gnunet-vpn-helper-p.h
@@ -0,0 +1,9 @@
+#ifndef GN_VPN_HELPER_P_H
+#define GN_VPN_HELPER_P_H
+
+struct suid_packet {
+        unsigned int size;
+        unsigned char data[1];
+};
+
+#endif
diff --git a/src/vpn/gnunet-vpn-helper.c b/src/vpn/gnunet-vpn-helper.c
new file mode 100644
index 000000000..66af3ca51
--- /dev/null
+++ b/src/vpn/gnunet-vpn-helper.c
@@ -0,0 +1,82 @@
+#define _GNU_SOURCE
+#include <arpa/inet.h>
+#include <linux/if.h>
+
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/ioctl.h>
+
+#include <string.h>
+
+#include <stdio.h>
+#include <unistd.h>
+
+#include "gnunet-vpn-helper-p.h"
+#include "tun.h"
+
+#ifndef _LINUX_IN6_H
+// This is in linux/include/net/ipv6.h.
+
+struct in6_ifreq {
+    struct in6_addr ifr6_addr;
+    __u32 ifr6_prefixlen;
+    unsigned int ifr6_ifindex;
+};
+
+#endif
+
+static void set_address(char* dev, char* address, unsigned long prefix_len) { /* {{{ */
+        int fd = socket(AF_INET6, SOCK_DGRAM, 0);
+
+        struct ifreq ifr;
+        struct in6_ifreq ifr6;
+
+        struct sockaddr_in6 sa6;
+        memset(&sa6, 0, sizeof(struct sockaddr_in6));
+
+        sa6.sin6_family = AF_INET6;
+
+        /* FIXME */ inet_pton(AF_INET6, address, sa6.sin6_addr.s6_addr);
+
+        memcpy((char *) &ifr6.ifr6_addr, (char *) &sa6.sin6_addr, sizeof(struct in6_addr));
+
+        strncpy(ifr.ifr_name, dev, IFNAMSIZ);
+
+        if (ioctl(fd, SIOGIFINDEX, &ifr) < 0) {
+                perror("SIOGIFINDEX");
+        }
+
+        ifr6.ifr6_ifindex = ifr.ifr_ifindex;
+        ifr6.ifr6_prefixlen = prefix_len;
+
+        if (ioctl(fd, SIOCSIFADDR, &ifr6) < 0) {
+                perror("SIOCSIFADDR");
+        }
+
+        /* FIXME */ ioctl(fd, SIOCGIFFLAGS, &ifr);
+        ifr.ifr_flags |= IFF_UP | IFF_RUNNING;
+        /* FIXME */ ioctl(fd, SIOCSIFFLAGS, &ifr);
+} /* }}} */
+
+int main(int argc, char** argv) {
+        char dev[IFNAMSIZ];
+        memset(dev, 0, IFNAMSIZ);
+
+        int fd_tun = init_tun(dev);
+        fprintf(stderr, "Initialized the interface %s as %d.\n", dev, fd_tun);
+
+        // TODO: get this out of argv
+        char address[] = "1234::1";
+        unsigned long prefix_len = 8;
+
+        set_address(dev, address, prefix_len);
+
+        uid_t uid = getuid ();
+        if (setresuid (uid, uid, uid) != 0 )
+                fprintf (stderr, "Failed to setresuid: %m\n");
+
+        // Wait
+        read(0, dev, 10);
+
+        return 0;
+}
diff --git a/src/vpn/tun.c b/src/vpn/tun.c
index d3c38bb4d..e3854495f 100644
--- a/src/vpn/tun.c
+++ b/src/vpn/tun.c
@@ -13,83 +13,39 @@
 #include <errno.h>
 #include <stdlib.h>
 
-#include "debug.h"
-
 /**
  * Creates a tun-interface called dev;
+ * dev is asumed to point to a char[IFNAMSIZ]
  * if *dev == 0, uses the name supplied by the kernel
  * returns the fd to the tun or -1
  */
-int init_tun(char *dev) { /*{{{*/
+int init_tun(char *dev) {{{
+        if (!dev) {
+                errno = EINVAL;
+                return -1;
+        }
+
         struct ifreq ifr;
         int fd, err;
 
         if( (fd = open("/dev/net/tun", O_RDWR)) < 0 ) {
-                debug(1, 0, "opening /dev/net/tun: %s\n", strerror(errno));
+                fprintf(stderr, "opening /dev/net/tun: %m\n");
                 return -1;
         }
 
         memset(&ifr, 0, sizeof(ifr));
 
-        ifr.ifr_flags = IFF_TUN; 
-        if(dev)
+        ifr.ifr_flags = IFF_TUN;
+
+        if (*dev)
                 strncpy(ifr.ifr_name, dev, IFNAMSIZ);
 
         if ((err = ioctl(fd, TUNSETIFF, (void *) &ifr)) < 0 ){
                 close(fd);
-                debug(1, 0, "ioctl'ing /dev/net/tun: %s\n", strerror(errno));
+                fprintf(stderr, "ioctl'ing /dev/net/tun: %m\n");
                 return err;
         }
+
         strcpy(dev, ifr.ifr_name);
         return fd;
-} /*}}}*/
-
-void n2o(int fd) {
-        char buf[1024];
-        int r, w;
-        for(;;) {
-                r = read(fd, buf, 1024);
-                if (r < 0) {
-                        fprintf(stderr, "n2o read: %s\n", strerror(errno));
-                        exit(1);
-                }
-                if (r == 0) {
-                        close(fd);
-                        exit(0);
-                }
-                while (r > 0) {
-                        w = write(1, buf, r);
-                        if (w < 0) {
-                                fprintf(stderr, "n2o write: %s\n", strerror(errno));
-                                close(fd);
-                                exit(1);
-                        }
-                        r -= w;
-                }
-        }
-}
-
-void o2n(int fd) {
-        char buf[1024];
-        int r, w;
-        for(;;) {
-                r = read(0, buf, 1024);
-                if (r < 0) {
-                        fprintf(stderr, "o2n read: %s\n", strerror(errno));
-                        exit(1);
-                }
-                if (r == 0) {
-                        close(fd);
-                        exit(0);
-                }
-                while (r > 0) {
-                        w = write(fd, buf, r);
-                        if (w < 0) {
-                                fprintf(stderr, "o2n write: %s\n", strerror(errno));
-                                close(fd);
-                                exit(1);
-                        }
-                        r -= w;
-                }
-        }
-}
+}}}