libggnet: traceroute sends packets in TCP and ICMP

4 files changed, 117 insertions, 65 deletions

diff --git a/libglouglou/examples/traceroute.c b/libglouglou/examples/traceroute.c
index b5d89b1..9d76a7d 100644
--- a/libglouglou/examples/traceroute.c
+++ b/libglouglou/examples/traceroute.c
@@ -17,10 +17,11 @@
 #include <string.h>
 #include <err.h>
 
+#include <libglouglou.h> /* for get_iface */
 #include <libggnet_traceroute.h>
 
 static void _droppriv(char *, int, char *);
-static void _cb_traceroute(struct in_addr *,
+static void _cb_traceroute(struct addr *,
 		struct ggnet_traceroute_req *, void *);
 
 struct event_base *_ev_base;
@@ -32,32 +33,31 @@ main(int argc, char *argv[])
 {
 	struct ggnet_traceroute *ggtr;
 	struct ggnet_traceroute_hop *hop;
-	struct in_addr ip;
+	struct addr ip;
 	struct timeval tv;
 
 	if (argc < 2) {
 		printf("usage: traceroute <ip>\n");
 		exit(1);
 	}
-	inet_aton(argv[1], &ip);
-	ip.s_addr = ntohl(ip.s_addr);
+	addr_aton(argv[1], &ip);
 
 	bzero(&tv, sizeof(struct timeval));
 	tv.tv_sec = 10;
 
 	_ev_base = event_base_new();
 
-	ggtr = ggnet_traceroute_new(_ev_base, "lo"); // XXX rm iface
+	ggtr = ggnet_traceroute_new(_ev_base, get_iface(argv[1]));
 	_droppriv("nobody", 1, NULL); /* bad practise you should use dedicated user */
-	ggnet_traceroute_trace(ggtr, &ip, _cb_traceroute, NULL);
+	ggnet_traceroute_trace(ggtr, &ip, TRACEMODE_ICMP, _cb_traceroute, NULL);
 
 	event_base_loopexit(_ev_base, &tv);
 	event_base_dispatch(_ev_base);
 
 	if (_answer) {
-		printf("%x:\n", ip.s_addr);
-		LIST_FOREACH(hop, &_route->hops, entry) {
-			printf("%x (%d)\n", hop->ip.s_addr, hop->delay);
+		printf("%s:\n", addr_ntoa(&ip));
+		TAILQ_FOREACH(hop, &_route->hops_list, entry) {
+			printf("%s (%d)\n", addr_ntoa(&hop->ip), hop->delay);
 		}
 	} else {
 		printf("no answer\n");
@@ -94,7 +94,7 @@ _droppriv(char *user, int do_chroot, char *chroot_path)
 
 
 static void
-_cb_traceroute(struct in_addr *ip,
+_cb_traceroute(struct addr *ip,
 		struct ggnet_traceroute_req *route, void *data)
 {
 	_route = route;
diff --git a/libglouglou/libggnet_traceroute.c b/libglouglou/libggnet_traceroute.c
index 077d237..561f0aa 100644
--- a/libglouglou/libggnet_traceroute.c
+++ b/libglouglou/libggnet_traceroute.c
@@ -77,6 +77,8 @@
 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 void _cb_trace_timeout(evutil_socket_t, short, void *);
+static void _timeout_set(struct ggnet_traceroute_req *, int, int);
 static int pcap_dloff(pcap_t *); // XXX move to libggnet_utils ?
 
 struct trace_pkt {
@@ -85,6 +87,7 @@ struct trace_pkt {
 	} pkt_hdr_i;
 	union {
 		struct tcp_hdr tcp;
+		struct icmp_hdr icmp;
 	} pkt_hdr_t;
 };
 
@@ -107,14 +110,11 @@ ggnet_traceroute_new(struct event_base *ev_base, char *iface)
 		return NULL;
 	}
 	ggtr->pkt_rand = rand_open();
-
-	/* XXX
-	 * Get iface/route from route_open, route_get and pcap_lookupnet.
-	 * DNS server cannot be changed to another interface after this. */
+	ggtr->intf = intf_open();
 
 	ggtr->pcap = pcap_open_live(iface, 1500, 1, 500, ebuff);
 	if (ggtr->pcap == NULL)
-		err(1, "pcap_open_live()");
+		err(1, "pcap_open_live(%s)", iface);
 	ggtr->pcap_dllen = pcap_dloff(ggtr->pcap);
 	ggtr->pcap_fd = pcap_fileno(ggtr->pcap);
 
@@ -139,39 +139,55 @@ ggnet_traceroute_free(struct ggnet_traceroute *ggtr)
 
 struct ggnet_traceroute_req *
 ggnet_traceroute_trace(struct ggnet_traceroute *ggtr,
-		struct in_addr *ip,
-		void (*cb_usr)(struct in_addr *, struct ggnet_traceroute_req *, void *),
+		struct addr *ip, enum tracemode mode,
+		void (*cb_usr)(struct addr *, struct ggnet_traceroute_req *, void *),
 		void *data)
 {
 	struct ggnet_traceroute_req *req;
-	struct ggnet_traceroute_hop *target;
+	struct intf_entry intf_entry;
 
 	req = calloc(1, sizeof(struct ggnet_traceroute_req));
 	if (!req) {
 		printf("could not allocate ggnet_traceroute_req\n");
 		exit(1);
 	}
-	target = calloc(1, sizeof(struct ggnet_traceroute_hop));
-	if (!target) {
+	req->target = calloc(1, sizeof(struct ggnet_traceroute_hop));
+	if (!req->target) {
 		printf("cannot allocate ggnet_traceroute_hop\n");
 		exit(1);
 	}
 
-	addr_aton("127.0.0.1", &req->target->ip);
-	addr_aton("127.0.0.1", &req->srcip);
+	memcpy(&req->target->ip, ip, sizeof(struct addr));
+	if (intf_get_dst(ggtr->intf, &intf_entry, &req->target->ip) < 0) {
+		printf("error getting source IP for dest IP %s\n",
+				addr_ntoa(ip));
+		goto err;
+	}
+	memcpy(&req->srcip, &intf_entry.intf_addr, sizeof(struct addr));
+	req->mode = mode;
+	TAILQ_INIT(&req->hops_list);
 
-	req->ev_recv = event_new(ggtr->ev_base,
+	req->run.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,
+	event_add(req->run.ev_recv, NULL);
+	req->run.ev_send = event_new(ggtr->ev_base,
 			ggtr->pcap_fd, EV_WRITE, _cb_send, req);
-	event_add(req->ev_send, NULL);
+	event_add(req->run.ev_send, NULL);
+	req->run.ev_timeout = evtimer_new(ggtr->ev_base,
+			_cb_trace_timeout, req);
+	event_add(req->run.ev_timeout, NULL);
 
-	// XXX evtimer timeout !!!
-	evtimer_new(ggtr->ev_base, _cb_trace_timeout, req);
+	req->cb_usr = cb_usr;
+	req->data = data;
+	req->ggtr = ggtr;
 
 	LIST_INSERT_HEAD(&ggtr->req_list, req, entry);
 	return req;
+
+err:
+	if (req)
+		_req_free(req);
+	return NULL;
 }
 
 void
@@ -186,18 +202,21 @@ ggnet_traceroute_cancel(struct ggnet_traceroute *ggtr,
 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);
+	if (req->target)
+		free(req->target);
+	if (req->run.ev_recv)
+		event_free(req->run.ev_recv);
+	if (req->run.ev_send)
+		event_free(req->run.ev_send);
 	free(req);
 }
 
 static void
 _cb_recv(evutil_socket_t fd, short what, void *arg)
 {
-	struct ggnet_traceroute_hop *hop;
 	struct ggnet_traceroute_req *req;
+#if 0
+	struct ggnet_traceroute_hop *hop;
 	struct ggnet_traceroute *ggtr;
 	struct pcap_pkthdr ph;
 	u_char *pread, *tmp;
@@ -207,8 +226,12 @@ _cb_recv(evutil_socket_t fd, short what, void *arg)
 	struct addr ip_src;
 	char  *reply = "U!";
 	char  *p;
+#endif
 
-	printf("cbggnet_traceroute cb_recv %s\n", addr_ntoa(&req->target->ip));
+	req = arg;
+	printf("XXX cbggnet_traceroute cb_recv %s -> %s\n",
+			addr_ntoa(&req->srcip), addr_ntoa(&req->target->ip));
+#if 0
 	req = arg;
 	ggtr = req->ggtr;
 
@@ -286,25 +309,27 @@ _cb_recv(evutil_socket_t fd, short what, void *arg)
 	fflush(stdout);
 
 	/* do we need to send more packets ? */
+#endif // if 0
 }
 
 static void
 _cb_send(evutil_socket_t fd, short what, void *arg)
 {
 	struct ggnet_traceroute_req *req;
+	struct ggnet_traceroute_hop *hop;
 	struct ggnet_traceroute *ggtr;
 	u_char buf[BUFSIZ];
 	struct trace_pkt *pkt;
-	int len;
-	int ttl;
+	int len, lensent, ttl, i;
 
-	printf("cbggnet_traceroute cb_send %s\n", addr_ntoa(&req->ip));
 	req = arg;
+	printf("XXX cbggnet_traceroute cb_send %s -> %s\n",
+			addr_ntoa(&req->srcip), addr_ntoa(&req->target->ip));
 	ggtr = req->ggtr;
 	pkt = (struct trace_pkt *)buf;
 	len = IP_HDR_LEN + TCP_HDR_LEN;
 
-	for (ttl=req->ttl_sent; i<15; i++) {
+	for (ttl=req->run.last_ttl_sent; ttl<15; ttl++) {
 		hop = calloc(1, sizeof(struct ggnet_traceroute_hop));
 		if (!hop) {
 			printf("cannot allocate ggnet_traceroute_hop\n");
@@ -312,53 +337,73 @@ _cb_send(evutil_socket_t fd, short what, void *arg)
 		}
 		hop->ttl = ttl;
 		//addr_pack(hop->ip, ADDR_TYPE_IP, IP_ADDR_BITS, ip, IP_ADDR_LEN);
-		ip_pack_hdr(&pkt->pkt_hdr_i.ip, IP_TOS_LOWDELAY, len, 
-				rand_uint16(ggtr->pkt_rand), 0, ttl, IP_PROTO_TCP, 
-				req->src.addr_ip, req->dst.addr_ip);
-		tcp_pack_hdr(&pkt->pkt_hdr_t.tcp, rand_uint16(ggtr->pkt_rand), TRACE_DPORT, 
-				rand_uint32(ggtr->pkt_rand), rand_uint32(ggtr->pkt_rand), 
+		switch (req->mode) {
+		case TRACEMODE_AUTO:
+		case TRACEMODE_TCP:
+			ip_pack_hdr(&pkt->pkt_hdr_i.ip, IP_TOS_LOWDELAY, len,
+				rand_uint16(ggtr->pkt_rand), 0, ttl,
+				IP_PROTO_TCP, 
+				req->srcip.addr_ip, req->target->ip.addr_ip);
+			tcp_pack_hdr(&pkt->pkt_hdr_t.tcp,
+				rand_uint16(ggtr->pkt_rand), TRACE_DPORT, 
+				rand_uint32(ggtr->pkt_rand), 0, 
 				TH_SYN, rand_uint16(ggtr->pkt_rand), 0);
+		case TRACEMODE_ICMP:
+			ip_pack_hdr(&pkt->pkt_hdr_i.ip, IP_TOS_LOWDELAY, len,
+				rand_uint16(ggtr->pkt_rand), 0, ttl,
+				IP_PROTO_ICMP, 
+				req->srcip.addr_ip, req->target->ip.addr_ip);
+			icmp_pack_hdr(&pkt->pkt_hdr_t.icmp, ICMP_ECHO, 8);
+		}
 		ip_checksum(pkt, len);
 		TAILQ_INSERT_TAIL(&req->hops_list, hop, entry);
 		for (i=0; i<TRACEROUTE_NB_PROBES; i++)
-			if (ip_send(ggtr->pkt_ip, pkt, len) < 0)
-				warn("_cb_send : ip_send short send");
+			lensent = ip_send(ggtr->pkt_ip, pkt, len);
+			if (len < 0)
+				warn("_cb_send : ip_send error");
+			if (lensent < len)
+				warn("_cb_send : ip_send short send (%d < %d",
+						lensent, len);
 		_timeout_set(req, TIMEOUT_TOTAL_S, 0);
 	}
-	req->ttl_sent = ttl;
+	req->run.last_ttl_sent = ttl;
 }
 
 static void
 _timeout_set(struct ggnet_traceroute_req *req, int sec, int usec)
 {
 	evtimer_del(req->run.ev_timeout);
-	req->run.tv_timeout.secs = sec;
-	req->run.tv_timeout.usecs = usec;
-	evtimer_add(req->run.ev_timeout, req->run.tv_timeout);
+	req->run.tv_timeout.tv_sec = sec;
+	req->run.tv_timeout.tv_usec = usec;
+	evtimer_add(req->run.ev_timeout, &req->run.tv_timeout);
 }
 
-static ggnet_traceroute_hop *
-_hop_last(ggnet_traceroute_req *req)
+static struct ggnet_traceroute_hop *
+_hop_last(struct ggnet_traceroute_req *req)
 {
 	struct ggnet_traceroute_hop *h;
 
-	TAILQ_FOREACH_REVERSE(h, req->hop_list, entry) {
+	TAILQ_FOREACH_REVERSE(h, &req->hops_list, tailhead, entry) {
 		if (h->answer_count > 0)
 			return h;
 	}
 	return NULL;
 }
 
-void
+static void
 _cb_trace_timeout(evutil_socket_t fd, short what, void *arg)
 {
 	struct ggnet_traceroute_req *req;
+	struct ggnet_traceroute_hop *last;
 
 	req = arg;
 
-	// XXX IN PROGRESS
+	printf("XXX cbggnet_traceroute cb_trace_timeout (%s -> %s)\n",
+			addr_ntoa(&req->srcip), addr_ntoa(&req->target->ip));
 	last = _hop_last(req);
-	req->target->ttl = last->ttl + 1;
+	if (last)
+		req->target->ttl = last->ttl + 1;
+	req->cb_usr(&req->srcip, req, req->data);
 }
 
 static int
diff --git a/libglouglou/libggnet_traceroute.h b/libglouglou/libggnet_traceroute.h
index 92b2d43..5699bfb 100644
--- a/libglouglou/libggnet_traceroute.h
+++ b/libglouglou/libggnet_traceroute.h
@@ -10,6 +10,12 @@
 
 #define TRACEROUTE_NB_PROBES 3
 
+enum tracemode {
+	TRACEMODE_AUTO = 0,
+	TRACEMODE_ICMP = 1,
+	TRACEMODE_TCP = 2,
+};
+
 struct ggnet_traceroute_hop {
 	TAILQ_ENTRY(ggnet_traceroute_hop) entry;
 	int	ttl;
@@ -25,25 +31,28 @@ struct ggnet_traceroute_hop {
 
 struct ggnet_traceroute_req {
 	LIST_ENTRY(ggnet_traceroute_req) entry;
-	struct	ggnet_traceroute_hop *target;
-	struct	addr srcip;
+	struct ggnet_traceroute_hop *target;
+	struct addr srcip;
+	enum tracemode mode;
 	int	probes_count;
 	int	hops_count;
-	TAILQ_HEAD(, ggnet_traceroute_hop) hops_list;
+	TAILQ_HEAD(tailhead, ggnet_traceroute_hop) hops_list;
 	struct {
 		struct event *ev_recv;
 		struct event *ev_send;
-		struct evtimer *ev_timeout;
+		struct event *ev_timeout;
 		struct timeval tv_timeout;
 		int last_ttl_sent;
 	} run;
-	void (*cb_usr)(struct in_addr *, char *, void *);
+	void (*cb_usr)(struct addr *, struct ggnet_traceroute_req *, void *);
 	void  *data;
+	struct ggnet_traceroute *ggtr;
 };
 
 struct ggnet_traceroute {
 	struct event_base *ev_base;
 	pcap_t	*pcap;
+	intf_t	*intf;
 	ip_t	*pkt_ip;
 	rand_t	*pkt_rand;
 	int      pcap_fd;
@@ -57,8 +66,8 @@ struct ggnet_traceroute *
 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 *),
+			struct addr *ip, enum tracemode,
+			void (*cb_usr)(struct addr *, struct ggnet_traceroute_req *, void *),
 			void *);
 void		ggnet_traceroute_cancel(struct ggnet_traceroute *,
 			struct ggnet_traceroute_req *);
diff --git a/libglouglou/utils.c b/libglouglou/utils.c
index 2f5f710..a7ceffd 100644
--- a/libglouglou/utils.c
+++ b/libglouglou/utils.c
@@ -205,14 +205,12 @@ get_iface(char *ip) {
 	struct addr dst;
 	struct intf_entry entry;
 	intf_t *intf;
-	char *iface;
 
 	intf = intf_open();
 	addr_aton(ip, &dst);
 	if (intf_get_dst(intf, &entry, &dst) < 0)
 		return NULL;
-	iface = addr_ntoa(&entry.intf_addr);
 	intf_close(intf);
 
-	return iface;
+	return strdup(entry.intf_name);
 }