traceroute: cleanup and fixes for packet size calculations
Remove FEATURE_TRACEROUTE_SOURCE_ROUTE: it's off by default, and
source routing is not used in real world.
Tested that "traceroute -n ::1 100" and "traceroute -n 127.0.0.1 100"
both send 100 byte IP packets (this matches what traceroute on Fedora
Rawhide is doing).
function old new delta
common_traceroute_main 3731 3738 +7
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/networking/traceroute.c b/networking/traceroute.c
index e43a36d..b9a9ca4 100644
--- a/networking/traceroute.c
+++ b/networking/traceroute.c
@@ -212,8 +212,7 @@
//usage:#define traceroute_trivial_usage
//usage: "[-"IF_TRACEROUTE6("46")"FIlnrv] [-f 1ST_TTL] [-m MAXTTL] [-q PROBES] [-p PORT]\n"
-//usage: " [-t TOS] [-w WAIT_SEC]"
-//usage: IF_FEATURE_TRACEROUTE_SOURCE_ROUTE(" [-g GATEWAY]")" [-s SRC_IP] [-i IFACE]\n"
+//usage: " [-t TOS] [-w WAIT_SEC] [-s SRC_IP] [-i IFACE]\n"
//usage: " [-z PAUSE_MSEC] HOST [BYTES]"
//usage:#define traceroute_full_usage "\n\n"
//usage: "Trace the route to HOST\n"
@@ -294,7 +293,6 @@
#define OPT_STRING \
"FIlnrdvxt:i:m:p:q:s:w:z:f:" \
- IF_FEATURE_TRACEROUTE_SOURCE_ROUTE("g:*") \
"4" IF_TRACEROUTE6("6")
enum {
OPT_DONT_FRAGMNT = (1 << 0), /* F */
@@ -314,9 +312,8 @@
OPT_WAITTIME = (1 << 14), /* w */
OPT_PAUSE_MS = (1 << 15), /* z */
OPT_FIRST_TTL = (1 << 16), /* f */
- OPT_SOURCE_ROUTE = (1 << 17) * ENABLE_FEATURE_TRACEROUTE_SOURCE_ROUTE, /* g */
- OPT_IPV4 = (1 << (17+ENABLE_FEATURE_TRACEROUTE_SOURCE_ROUTE)), /* 4 */
- OPT_IPV6 = (1 << (18+ENABLE_FEATURE_TRACEROUTE_SOURCE_ROUTE)) * ENABLE_TRACEROUTE6, /* 6 */
+ OPT_IPV4 = (1 << 17), /* 4 */
+ OPT_IPV6 = (1 << 18) * ENABLE_TRACEROUTE6, /* 6 */
};
#define verbose (option_mask32 & OPT_VERBOSE)
@@ -343,26 +340,18 @@
#endif
struct globals {
+ /* Pointer to entire malloced IP packet, "packlen" bytes long: */
struct ip *outip;
+ /* Pointer to ICMP or UDP payload (not header): */
struct outdata_t *outdata;
+
len_and_sockaddr *dest_lsa;
int packlen; /* total length of packet */
int pmtu; /* Path MTU Discovery (RFC1191) */
uint32_t ident;
- uint16_t port; // 32768 + 666; /* start udp dest port # for probe packets */
+ uint16_t port; // 33434; /* start udp dest port # for probe packets */
int waittime; // 5; /* time to wait for response (in seconds) */
-#if ENABLE_FEATURE_TRACEROUTE_SOURCE_ROUTE
- int optlen; /* length of ip options */
-#else
-#define optlen 0
-#endif
unsigned char recv_pkt[512]; /* last inbound (icmp) packet */
-#if ENABLE_FEATURE_TRACEROUTE_SOURCE_ROUTE
- /* Maximum number of gateways (include room for one noop) */
-#define NGATEWAYS ((int)((MAX_IPOPTLEN - IPOPT_MINOFF - 1) / sizeof(uint32_t)))
- /* loose source route gateway list (including room for final destination) */
- uint32_t gwlist[NGATEWAYS + 1];
-#endif
};
#define G (*ptr_to_globals)
@@ -374,14 +363,11 @@
#define ident (G.ident )
#define port (G.port )
#define waittime (G.waittime )
-#if ENABLE_FEATURE_TRACEROUTE_SOURCE_ROUTE
-# define optlen (G.optlen )
-#endif
#define recv_pkt (G.recv_pkt )
#define gwlist (G.gwlist )
#define INIT_G() do { \
SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
- port = 32768 + 666; \
+ port = 33434; \
waittime = 5; \
} while (0)
@@ -421,7 +407,7 @@
/* Payload */
#if ENABLE_TRACEROUTE6
if (dest_lsa->u.sa.sa_family == AF_INET6) {
- struct outdata6_t *pkt = (struct outdata6_t *) outip;
+ struct outdata6_t *pkt = (struct outdata6_t *) outdata;
pkt->ident6 = htonl(ident);
pkt->seq6 = htonl(seq);
/*gettimeofday(&pkt->tv, &tz);*/
@@ -438,8 +424,10 @@
/* Always calculate checksum for icmp packets */
outicmp->icmp_cksum = 0;
- outicmp->icmp_cksum = inet_cksum((uint16_t *)outicmp,
- packlen - (sizeof(*outip) + optlen));
+ outicmp->icmp_cksum = inet_cksum(
+ (uint16_t *)outicmp,
+ ((char*)outip + packlen) - (char*)outicmp
+ );
if (outicmp->icmp_cksum == 0)
outicmp->icmp_cksum = 0xffff;
}
@@ -471,13 +459,12 @@
}
#endif
+ out = outdata;
#if ENABLE_TRACEROUTE6
if (dest_lsa->u.sa.sa_family == AF_INET6) {
res = setsockopt_int(sndsock, SOL_IPV6, IPV6_UNICAST_HOPS, ttl);
if (res != 0)
bb_perror_msg_and_die("setsockopt(%s) %d", "UNICAST_HOPS", ttl);
- out = outip;
- len = packlen;
} else
#endif
{
@@ -486,15 +473,14 @@
if (res != 0)
bb_perror_msg_and_die("setsockopt(%s) %d", "TTL", ttl);
#endif
- out = outicmp;
- len = packlen - sizeof(*outip);
- if (!(option_mask32 & OPT_USE_ICMP)) {
- out = outdata;
- len -= sizeof(*outudp);
- set_nport(&dest_lsa->u.sa, htons(port + seq));
- }
+ if (option_mask32 & OPT_USE_ICMP)
+ out = outicmp;
}
+ if (!(option_mask32 & OPT_USE_ICMP)) {
+ set_nport(&dest_lsa->u.sa, htons(port + seq));
+ }
+ len = ((char*)outip + packlen) - (char*)out;
res = xsendto(sndsock, out, len, &dest_lsa->u.sa, dest_lsa->len);
if (res != len)
bb_error_msg("sent %d octets, ret=%d", len, res);
@@ -801,10 +787,6 @@
char *pausemsecs_str;
char *first_ttl_str;
char *dest_str;
-#if ENABLE_FEATURE_TRACEROUTE_SOURCE_ROUTE
- llist_t *source_route_list = NULL;
- int lsrr = 0;
-#endif
#if ENABLE_TRACEROUTE6
sa_family_t af;
#else
@@ -823,9 +805,6 @@
op |= getopt32(argv, OPT_STRING
, &tos_str, &device, &max_ttl_str, &port_str, &nprobes_str
, &source, &waittime_str, &pausemsecs_str, &first_ttl_str
-#if ENABLE_FEATURE_TRACEROUTE_SOURCE_ROUTE
- , &source_route_list
-#endif
);
argv += optind;
@@ -858,26 +837,14 @@
if (op & OPT_FIRST_TTL)
first_ttl = xatou_range(first_ttl_str, 1, max_ttl);
-#if ENABLE_FEATURE_TRACEROUTE_SOURCE_ROUTE
- if (source_route_list) {
- while (source_route_list) {
- len_and_sockaddr *lsa;
-
- if (lsrr >= NGATEWAYS)
- bb_error_msg_and_die("no more than %d gateways", NGATEWAYS);
- lsa = xhost_and_af2sockaddr(llist_pop(&source_route_list), 0, AF_INET);
- gwlist[lsrr] = lsa->u.sin.sin_addr.s_addr;
- free(lsa);
- ++lsrr;
- }
- optlen = (lsrr + 1) * sizeof(gwlist[0]);
- }
-#endif
-
/* Process destination and optional packet size */
- minpacket = sizeof(*outip) + SIZEOF_ICMP_HDR + sizeof(*outdata) + optlen;
+ minpacket = sizeof(struct ip)
+ + SIZEOF_ICMP_HDR
+ + sizeof(struct outdata_t);
if (!(op & OPT_USE_ICMP))
- minpacket += sizeof(*outudp) - SIZEOF_ICMP_HDR;
+ minpacket = sizeof(struct ip)
+ + sizeof(struct udphdr)
+ + sizeof(struct outdata_t);
#if ENABLE_TRACEROUTE6
af = AF_UNSPEC;
if (op & OPT_IPV4)
@@ -887,7 +854,9 @@
dest_lsa = xhost_and_af2sockaddr(argv[0], port, af);
af = dest_lsa->u.sa.sa_family;
if (af == AF_INET6)
- minpacket = sizeof(struct outdata6_t);
+ minpacket = sizeof(struct ip6_hdr)
+ + sizeof(struct udphdr)
+ + sizeof(struct outdata6_t);
#else
dest_lsa = xhost2sockaddr(argv[0], port);
#endif
@@ -932,31 +901,6 @@
xmove_fd(xsocket(AF_INET, SOCK_RAW, IPPROTO_ICMP), sndsock);
else
xmove_fd(xsocket(AF_INET, SOCK_DGRAM, 0), sndsock);
-#if ENABLE_FEATURE_TRACEROUTE_SOURCE_ROUTE && defined IP_OPTIONS
- if (lsrr > 0) {
- unsigned char optlist[MAX_IPOPTLEN];
- unsigned size;
-
- /* final hop */
- gwlist[lsrr] = dest_lsa->u.sin.sin_addr.s_addr;
- ++lsrr;
-
- /* force 4 byte alignment */
- optlist[0] = IPOPT_NOP;
- /* loose source route option */
- optlist[1] = IPOPT_LSRR;
- size = lsrr * sizeof(gwlist[0]);
- optlist[2] = size + 3;
- /* pointer to LSRR addresses */
- optlist[3] = IPOPT_MINOFF;
- memcpy(optlist + 4, gwlist, size);
-
- if (setsockopt(sndsock, IPPROTO_IP, IP_OPTIONS,
- (char *)optlist, size + sizeof(gwlist[0])) < 0) {
- bb_perror_msg_and_die("IP_OPTIONS");
- }
- }
-#endif
}
#ifdef SO_SNDBUF
@@ -984,7 +928,7 @@
ident = getpid();
- if (af == AF_INET) {
+ if (!ENABLE_TRACEROUTE6 || af == AF_INET) {
if (op & OPT_USE_ICMP) {
ident |= 0x8000;
outicmp->icmp_type = ICMP_ECHO;
@@ -994,6 +938,14 @@
outdata = (struct outdata_t *)(outudp + 1);
}
}
+#if ENABLE_TRACEROUTE6
+ if (af == AF_INET6) {
+ outdata = (void*)((char*)outip
+ + sizeof(struct ip6_hdr)
+ + sizeof(struct udphdr)
+ );
+ }
+#endif
if (op & OPT_DEVICE) /* hmm, do we need error check? */
setsockopt_bindtodevice(sndsock, device);