work on traceroute, initialisation code is there now

3 files changed, 186 insertions, 19 deletions

diff --git a/libglouglou/examples/traceroute.c b/libglouglou/examples/traceroute.c
index 9d3e218..080274f 100644
--- a/libglouglou/examples/traceroute.c
+++ b/libglouglou/examples/traceroute.c
@@ -1,11 +1,25 @@
+#include <sys/types.h>
+
+#if !defined(__OpenBSD__)
+#define __USE_GNU
+#define _GNU_SOURCE
+#endif
+
+#include <unistd.h>
 #include <stdlib.h>
 #include <string.h>
 #include <sys/socket.h>
 #include <netinet/in.h>
 #include <arpa/inet.h>
 
+#include <pwd.h>
+#include <grp.h>
+#include <string.h>
+#include <err.h>
+
 #include <libggnet_traceroute.h>
 
+static void _droppriv(char *, int, char *);
 static void _cb_traceroute(struct in_addr *,
                            struct ggnet_traceroute_req *, void *);
 
@@ -29,20 +43,21 @@ main(int argc, char *argv[])
   ip.s_addr = ntohl(ip.s_addr);
 
   bzero(&tv, sizeof(struct timeval));
-  tv.tv_sec = 5;
+  tv.tv_sec = 10;
 
   _ev_base = event_base_new();
 
-  ggtr = ggnet_traceroute_new(_ev_base);
-  ggnet_traceroute_reverse(ggtr, &ip, _cb_traceroute, NULL);
+  ggtr = ggnet_traceroute_new(_ev_base, "lo"); // XXX rm iface
+  _droppriv("nobody", 1, NULL); /* bad practise you should use dedicated user */
+  ggnet_traceroute_trace(ggtr, &ip, _cb_traceroute, NULL);
 
   event_base_loopexit(_ev_base, &tv);
   event_base_dispatch(_ev_base);
 
   if (_answer) {
     printf("%x:\n", ip.s_addr);
-    LIST_FOREACH(&_route->hops, h, entry) {
-      printf("%x (%d)\n", h->ip.s_addr, h->delay);
+    LIST_FOREACH(hop, &_route->hops, entry) {
+      printf("%x (%d)\n", hop->ip.s_addr, hop->delay);
     }
   } else {
     printf("no answer\n");
@@ -50,9 +65,37 @@ main(int argc, char *argv[])
   return 0;
 }
 
+/* from libglouglou utils.c */
+static void
+_droppriv(char *user, int do_chroot, char *chroot_path)
+{
+	struct passwd	*pw;
+
+	pw = getpwnam(user);
+	if (!pw)
+		err(1, "unknown user %s", user);
+	if (do_chroot) {
+    if (!chroot_path)
+      chroot_path = pw->pw_dir;
+    if (chroot(chroot_path) != 0)
+      err(1, "unable to chroot");
+  }
+	if (chdir("/") != 0)
+		err(1, "unable to chdir");
+	if (setgroups(1, &pw->pw_gid) == -1)
+		err(1, "setgroups() failed");
+	if (setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) == -1)
+		err(1, "setresgid failed");
+	if (setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid) == -1)
+		err(1, "setresuid() failed");
+	endpwent();
+	printf("droppriv done\n");
+}
+
+
 static void
 _cb_traceroute(struct in_addr *ip,
-               struct ggnet_traceroute_req *route, void *data);
+               struct ggnet_traceroute_req *route, void *data)
 {
   _route = route;
   _answer = 1;
diff --git a/libglouglou/libggnet_traceroute.c b/libglouglou/libggnet_traceroute.c
index 3b8e6ed..f00fd72 100644
--- a/libglouglou/libggnet_traceroute.c
+++ b/libglouglou/libggnet_traceroute.c
@@ -8,10 +8,31 @@
  *   All rights reserved.
  */
 
+
+#include <sys/param.h>
+#include <sys/time.h>
+#include <sys/types.h>
+
+#include <netinet/in.h>
+#include <err.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <unistd.h>
+
+#include "libggnet_traceroute.h"
+
+static void _req_free(struct ggnet_traceroute_req *);
+static void _cb_recv(evutil_socket_t, short, void *);
+static void _cb_send(evutil_socket_t, short, void *);
+static int pcap_dloff(pcap_t *); // XXX move to libggnet_utils ?
+
 struct ggnet_traceroute *
-ggnet_traceroute_new(struct event_base *ev_base)
+ggnet_traceroute_new(struct event_base *ev_base, char *iface)
 {
   struct ggnet_traceroute *ggtr;
+	char ebuff[PCAP_ERRBUF_SIZE];
 
   ggtr = calloc(1, sizeof(struct ggnet_traceroute));
   if (!ggtr) {
@@ -19,18 +40,47 @@ ggnet_traceroute_new(struct event_base *ev_base)
     exit(1);
   }
   ggtr->ev_base = ev_base;
-  return ggdns;
+  ggtr->pkt_ip = ip_open();
+  if (!ggtr->pkt_ip) {
+    printf("ip_open() failed\n");
+    ggnet_traceroute_free(ggtr);
+    return NULL;
+  }
+	ggtr->pkt_rand = rand_open();
+
+
+  /* XXX get iface from route_open, route_get and pcap_lookupnet.
+   * will need to do so in ggnet_traceroute_trace() so user privs, so will need
+   * to prefetch the routes / interfaces, maybe */
+
+	ggtr->pcap = pcap_open_live(iface, 1500, 1, 500, ebuff);
+	if (ggtr->pcap == NULL)
+		err(1, "pcap_open_live()");
+	ggtr->pcap_dllen = pcap_dloff(ggtr->pcap);
+	ggtr->pcap_fd = pcap_fileno(ggtr->pcap);
+
+  return ggtr;
 }
 
 void
 ggnet_traceroute_free(struct ggnet_traceroute *ggtr)
 {
+  struct ggnet_traceroute_req *req;
+
+  if (ggtr->pcap)
+    pcap_close(ggtr->pcap);
+  if (ggtr->pkt_ip)
+    ip_close(ggtr->pkt_ip);
+  if (ggtr->pkt_rand)
+    rand_close(ggtr->pkt_rand);
+  LIST_FOREACH(req, &ggtr->req_list, entry)
+    _req_free(req);
   free(ggtr);
 }
 
 struct ggnet_traceroute_req *
 ggnet_traceroute_trace(struct ggnet_traceroute *ggtr,
-                       struct in_iddr *ip,
+                       struct in_addr *ip,
                        void (*cb_usr)(struct in_addr *, struct ggnet_traceroute_req *, void *),
                        void *data)
 {
@@ -42,6 +92,16 @@ ggnet_traceroute_trace(struct ggnet_traceroute *ggtr,
     exit(1);
   }
 
+  addr_aton("127.0.0.1", &req->srcip);
+  addr_aton("127.0.0.1", &req->ip);
+
+  req->ev_recv = event_new(ggtr->ev_base,
+                           ggtr->pcap_fd, EV_READ, _cb_recv, req);
+  event_add(req->ev_recv, NULL);
+  req->ev_send = event_new(ggtr->ev_base,
+                           ggtr->pcap_fd, EV_WRITE, _cb_send, req);
+  event_add(req->ev_send, NULL);
+
   LIST_INSERT_HEAD(&ggtr->req_list, req, entry);
   return req;
 }
@@ -52,5 +112,60 @@ ggnet_traceroute_cancel(struct ggnet_traceroute *ggtr,
 {
   LIST_REMOVE(req, entry);
   ggtr->req_pending--;
+  _req_free(req);
+}
+
+static void
+_req_free(struct ggnet_traceroute_req *req)
+{
+  if (req->ev_recv)
+    event_free(req->ev_recv);
+  if (req->ev_send)
+    event_free(req->ev_send);
   free(req);
 }
+
+static void
+_cb_recv(evutil_socket_t fd, short what, void *arg)
+{
+  struct ggnet_traceroute_req *req;
+
+  req = arg;
+  printf("cbggnet_traceroute cb_recv %s\n", addr_ntoa(&req->ip));
+}
+
+static void
+_cb_send(evutil_socket_t fd, short what, void *arg)
+{
+  struct ggnet_traceroute_req *req;
+
+  req = arg;
+  printf("cbggnet_traceroute cb_send %s\n", addr_ntoa(&req->ip));
+}
+
+static int
+pcap_dloff(pcap_t *pd)
+{
+	int i;
+
+	i = pcap_datalink(pd);
+	
+	switch (i) {
+	case DLT_EN10MB:
+		i = 14;
+		break;
+	case DLT_IEEE802:
+		i = 22;
+		break;
+	case DLT_FDDI:
+		i = 21;
+		break;
+	case DLT_NULL:
+		i = 4;
+		break;
+	default:
+		i = -1;
+		break;
+	}
+	return (i);
+}
diff --git a/libglouglou/libggnet_traceroute.h b/libglouglou/libggnet_traceroute.h
index 24aea02..0c19bea 100644
--- a/libglouglou/libggnet_traceroute.h
+++ b/libglouglou/libggnet_traceroute.h
@@ -1,6 +1,6 @@
-#include <event2/dns.h>
-#include <event2/util.h>
-#include <event2/event.h>
+#include <event.h>
+#include <dnet.h>
+#include <pcap.h>
 
 #if defined(__OpenBSD__)
 #include <sys/queue.h>
@@ -17,7 +17,11 @@ struct ggnet_traceroute_hop {
 
 struct ggnet_traceroute_req {
   LIST_ENTRY(ggnet_traceroute_req) entry;
-  struct event *ev;
+  struct event *ev_recv;
+  struct event *ev_send;
+  struct addr ip;
+  struct addr srcip;
+  int hops_count;
   LIST_HEAD(, ggnet_traceroute_hop) hops;
   void (*cb_usr)(struct in_addr *, char *, void *);
   void  *data;
@@ -25,15 +29,20 @@ struct ggnet_traceroute_req {
 
 struct ggnet_traceroute {
   struct event_base *ev_base;
+  pcap_t *pcap;
+  ip_t *pkt_ip;
+  rand_t *pkt_rand;
+  int     pcap_fd;
+	int		  pcap_dllen;		/* datalink layer hdr len */
   int req_pending;
-  LIST_HEAD(, ggnet_traceroute_req) req_list; /* XXX for now unused. remove ? */
+  LIST_HEAD(, ggnet_traceroute_req) req_list;
 };
 
-struct ggnet_traceroute     *ggnet_traceroute_new(struct event_base *);
-void                         ggnet_traceroute_free(struct ggnet_dns *);
-struct ggnet_traceroute_req *ggnet_traceroute_trace(struct ggnet_traceroute *ggtr,
-                                                    struct in_iddr *ip,
+struct ggnet_traceroute     *ggnet_traceroute_new(struct event_base *, char *);
+void                         ggnet_traceroute_free(struct ggnet_traceroute *);
+struct ggnet_traceroute_req *ggnet_traceroute_trace(struct ggnet_traceroute *,
+                                                    struct in_addr *ip,
                                                     void (*cb_usr)(struct in_addr *, struct ggnet_traceroute_req *, void *),
-                                                    void *data)
+                                                    void *);
 void                         ggnet_traceroute_cancel(struct ggnet_traceroute *,
                                                      struct ggnet_traceroute_req *);