Don't send malformed SCTP probe packets.

MFC after: 3 days

2 files changed, 156 insertions, 5 deletions

diff --git a/contrib/traceroute/traceroute.8 b/contrib/traceroute/traceroute.8
index 654b538536ce9..e7e9456576392 100644
--- a/contrib/traceroute/traceroute.8
+++ b/contrib/traceroute/traceroute.8
@@ -16,7 +16,7 @@
 .\"	$Id: traceroute.8,v 1.19 2000/09/21 08:44:19 leres Exp $
 .\"	$FreeBSD$
 .\"
-.Dd June 19, 2012
+.Dd May 31, 2015
 .Dt TRACEROUTE 8
 .Os
 .Sh NAME
@@ -65,7 +65,7 @@ Turn  on  AS#  lookups  and  use the given server instead of the
 default.
 .It Fl e
 Firewall evasion mode.
-Use fixed destination ports for UDP and TCP probes.
+Use fixed destination ports for UDP, TCP and SCTP probes.
 The destination port does NOT increment with each packet sent.
 .It Fl f Ar first_ttl
 Set the initial time-to-live used in the first outgoing probe packet.
@@ -110,14 +110,14 @@ Print hop addresses numerically rather than symbolically and numerically
 path).
 .It Fl P Ar proto
 Send packets of specified IP protocol. The currently supported protocols
-are: UDP, TCP, GRE and ICMP. Other protocols may also be specified (either by
-name or by number), though
+are: UDP, TCP, SCTP, GRE and ICMP. Other protocols may also be specified
+(either by name or by number), though
 .Nm
 does not implement any special knowledge of their packet formats. This
 option is useful for determining which router along a path may be
 blocking packets based on IP protocol number. But see BUGS below.
 .It Fl p Ar port
-Protocol specific. For UDP and TCP, sets
+Protocol specific. For UDP, TCP and SCTP, sets
 the base
 .Ar port
 number used in probes (default is 33434).
diff --git a/contrib/traceroute/traceroute.c b/contrib/traceroute/traceroute.c
index 8ecacfea95d80..2376a9b12e0bd 100644
--- a/contrib/traceroute/traceroute.c
+++ b/contrib/traceroute/traceroute.c
@@ -219,6 +219,7 @@ static const char rcsid[] =
 #include <netinet/ip.h>
 #include <netinet/ip_var.h>
 #include <netinet/ip_icmp.h>
+#include <netinet/sctp.h>
 #include <netinet/udp.h>
 #include <netinet/tcp.h>
 #include <netinet/tcpip.h>
@@ -367,6 +368,7 @@ void	freehostinfo(struct hostinfo *);
 void	getaddr(u_int32_t *, char *);
 struct	hostinfo *gethostinfo(char *);
 u_short	in_cksum(u_short *, int);
+u_int32_t sctp_crc32c(const void *, u_int32_t);
 char	*inetname(struct in_addr);
 int	main(int, char **);
 u_short p_cksum(struct ip *, u_short *, int);
@@ -391,6 +393,8 @@ void	udp_prep(struct outdata *);
 int	udp_check(const u_char *, int);
 void	tcp_prep(struct outdata *);
 int	tcp_check(const u_char *, int);
+void	sctp_prep(struct outdata *);
+int	sctp_check(const u_char *, int);
 void	gre_prep(struct outdata *);
 int	gre_check(const u_char *, int);
 void	gen_prep(struct outdata *);
@@ -433,6 +437,15 @@ struct	outproto protos[] = {
 		tcp_check
 	},
 	{
+		"sctp",
+		"spt dpt vtag    crc     tyfllen tyfllen ",
+		IPPROTO_SCTP,
+		sizeof(struct sctphdr),
+		32768 + 666,
+		sctp_prep,
+		sctp_check
+	},
+	{
 		"gre",
 		"flg pro len clid",
 		IPPROTO_GRE,
@@ -707,6 +720,11 @@ main(int argc, char **argv)
 #endif
 
 	protlen = packlen - sizeof(*outip) - optlen;
+	if ((proto->num == IPPROTO_SCTP) && (packlen & 3)) {
+		Fprintf(stderr, "%s: packet length must be a multiple of 4\n",
+		    prog);
+		exit(1);
+	}
 
 	outip = (struct ip *)malloc((unsigned)packlen);
 	if (outip == NULL) {
@@ -1432,6 +1450,47 @@ tcp_check(const u_char *data, int seq)
 }
 
 void
+sctp_prep(struct outdata *outdata)
+{
+	struct sctphdr *const sctp = (struct sctphdr *) outp;
+	struct sctp_chunkhdr *chk;
+
+	sctp->src_port = htons(ident);
+	sctp->dest_port = htons(port + (fixedPort ? 0 : outdata->seq));
+	sctp->v_tag = (sctp->src_port << 16) | sctp->dest_port;
+	sctp->checksum = htonl(0);
+	if (protlen >=
+	    (int)(sizeof(struct sctphdr) + sizeof(struct sctp_chunkhdr))) {
+		chk = (struct sctp_chunkhdr *)(sctp + 1);
+		chk->chunk_type = SCTP_SHUTDOWN_ACK;
+		chk->chunk_flags = 0;
+		chk->chunk_length = htons(4);
+	}
+	if (protlen >=
+	    (int)(sizeof(struct sctphdr) + 2 * sizeof(struct sctp_chunkhdr))) {
+		chk = chk + 1;
+		chk->chunk_type = SCTP_PAD_CHUNK;
+		chk->chunk_flags = 0;
+		chk->chunk_length = htons(protlen -
+		    (sizeof(struct sctphdr) + sizeof(struct sctp_chunkhdr)));
+	}
+	if (doipcksum) {
+		sctp->checksum = sctp_crc32c(sctp, protlen);
+	}
+}
+
+int
+sctp_check(const u_char *data, int seq)
+{
+	struct sctphdr *const sctp = (struct sctphdr *) data;
+
+	return (ntohs(sctp->src_port) == ident
+	    && ntohs(sctp->dest_port) == port + (fixedPort ? 0 : seq)
+	    && sctp->v_tag ==
+	    (u_int32_t)((sctp->src_port << 16) | sctp->dest_port));
+}
+
+void
 gre_prep(struct outdata *outdata)
 {
 	struct grehdr *const gre = (struct grehdr *) outp;
@@ -1550,6 +1609,98 @@ in_cksum(register u_short *addr, register int len)
 }
 
 /*
+ * CRC32C routine for the Stream Control Transmission Protocol
+ */
+
+#define CRC32C(c, d) (c = (c>>8) ^ crc_c[(c^(d))&0xFF])
+
+static u_int32_t crc_c[256] = {
+	0x00000000, 0xF26B8303, 0xE13B70F7, 0x1350F3F4,
+	0xC79A971F, 0x35F1141C, 0x26A1E7E8, 0xD4CA64EB,
+	0x8AD958CF, 0x78B2DBCC, 0x6BE22838, 0x9989AB3B,
+	0x4D43CFD0, 0xBF284CD3, 0xAC78BF27, 0x5E133C24,
+	0x105EC76F, 0xE235446C, 0xF165B798, 0x030E349B,
+	0xD7C45070, 0x25AFD373, 0x36FF2087, 0xC494A384,
+	0x9A879FA0, 0x68EC1CA3, 0x7BBCEF57, 0x89D76C54,
+	0x5D1D08BF, 0xAF768BBC, 0xBC267848, 0x4E4DFB4B,
+	0x20BD8EDE, 0xD2D60DDD, 0xC186FE29, 0x33ED7D2A,
+	0xE72719C1, 0x154C9AC2, 0x061C6936, 0xF477EA35,
+	0xAA64D611, 0x580F5512, 0x4B5FA6E6, 0xB93425E5,
+	0x6DFE410E, 0x9F95C20D, 0x8CC531F9, 0x7EAEB2FA,
+	0x30E349B1, 0xC288CAB2, 0xD1D83946, 0x23B3BA45,
+	0xF779DEAE, 0x05125DAD, 0x1642AE59, 0xE4292D5A,
+	0xBA3A117E, 0x4851927D, 0x5B016189, 0xA96AE28A,
+	0x7DA08661, 0x8FCB0562, 0x9C9BF696, 0x6EF07595,
+	0x417B1DBC, 0xB3109EBF, 0xA0406D4B, 0x522BEE48,
+	0x86E18AA3, 0x748A09A0, 0x67DAFA54, 0x95B17957,
+	0xCBA24573, 0x39C9C670, 0x2A993584, 0xD8F2B687,
+	0x0C38D26C, 0xFE53516F, 0xED03A29B, 0x1F682198,
+	0x5125DAD3, 0xA34E59D0, 0xB01EAA24, 0x42752927,
+	0x96BF4DCC, 0x64D4CECF, 0x77843D3B, 0x85EFBE38,
+	0xDBFC821C, 0x2997011F, 0x3AC7F2EB, 0xC8AC71E8,
+	0x1C661503, 0xEE0D9600, 0xFD5D65F4, 0x0F36E6F7,
+	0x61C69362, 0x93AD1061, 0x80FDE395, 0x72966096,
+	0xA65C047D, 0x5437877E, 0x4767748A, 0xB50CF789,
+	0xEB1FCBAD, 0x197448AE, 0x0A24BB5A, 0xF84F3859,
+	0x2C855CB2, 0xDEEEDFB1, 0xCDBE2C45, 0x3FD5AF46,
+	0x7198540D, 0x83F3D70E, 0x90A324FA, 0x62C8A7F9,
+	0xB602C312, 0x44694011, 0x5739B3E5, 0xA55230E6,
+	0xFB410CC2, 0x092A8FC1, 0x1A7A7C35, 0xE811FF36,
+	0x3CDB9BDD, 0xCEB018DE, 0xDDE0EB2A, 0x2F8B6829,
+	0x82F63B78, 0x709DB87B, 0x63CD4B8F, 0x91A6C88C,
+	0x456CAC67, 0xB7072F64, 0xA457DC90, 0x563C5F93,
+	0x082F63B7, 0xFA44E0B4, 0xE9141340, 0x1B7F9043,
+	0xCFB5F4A8, 0x3DDE77AB, 0x2E8E845F, 0xDCE5075C,
+	0x92A8FC17, 0x60C37F14, 0x73938CE0, 0x81F80FE3,
+	0x55326B08, 0xA759E80B, 0xB4091BFF, 0x466298FC,
+	0x1871A4D8, 0xEA1A27DB, 0xF94AD42F, 0x0B21572C,
+	0xDFEB33C7, 0x2D80B0C4, 0x3ED04330, 0xCCBBC033,
+	0xA24BB5A6, 0x502036A5, 0x4370C551, 0xB11B4652,
+	0x65D122B9, 0x97BAA1BA, 0x84EA524E, 0x7681D14D,
+	0x2892ED69, 0xDAF96E6A, 0xC9A99D9E, 0x3BC21E9D,
+	0xEF087A76, 0x1D63F975, 0x0E330A81, 0xFC588982,
+	0xB21572C9, 0x407EF1CA, 0x532E023E, 0xA145813D,
+	0x758FE5D6, 0x87E466D5, 0x94B49521, 0x66DF1622,
+	0x38CC2A06, 0xCAA7A905, 0xD9F75AF1, 0x2B9CD9F2,
+	0xFF56BD19, 0x0D3D3E1A, 0x1E6DCDEE, 0xEC064EED,
+	0xC38D26C4, 0x31E6A5C7, 0x22B65633, 0xD0DDD530,
+	0x0417B1DB, 0xF67C32D8, 0xE52CC12C, 0x1747422F,
+	0x49547E0B, 0xBB3FFD08, 0xA86F0EFC, 0x5A048DFF,
+	0x8ECEE914, 0x7CA56A17, 0x6FF599E3, 0x9D9E1AE0,
+	0xD3D3E1AB, 0x21B862A8, 0x32E8915C, 0xC083125F,
+	0x144976B4, 0xE622F5B7, 0xF5720643, 0x07198540,
+	0x590AB964, 0xAB613A67, 0xB831C993, 0x4A5A4A90,
+	0x9E902E7B, 0x6CFBAD78, 0x7FAB5E8C, 0x8DC0DD8F,
+	0xE330A81A, 0x115B2B19, 0x020BD8ED, 0xF0605BEE,
+	0x24AA3F05, 0xD6C1BC06, 0xC5914FF2, 0x37FACCF1,
+	0x69E9F0D5, 0x9B8273D6, 0x88D28022, 0x7AB90321,
+	0xAE7367CA, 0x5C18E4C9, 0x4F48173D, 0xBD23943E,
+	0xF36E6F75, 0x0105EC76, 0x12551F82, 0xE03E9C81,
+	0x34F4F86A, 0xC69F7B69, 0xD5CF889D, 0x27A40B9E,
+	0x79B737BA, 0x8BDCB4B9, 0x988C474D, 0x6AE7C44E,
+	0xBE2DA0A5, 0x4C4623A6, 0x5F16D052, 0xAD7D5351
+};
+
+u_int32_t
+sctp_crc32c(const void *packet, u_int32_t len)
+{
+	u_int32_t i, crc32c;
+	u_int8_t byte0, byte1, byte2, byte3;
+	const u_int8_t *buf = (const u_int8_t *)packet;
+
+	crc32c = ~0;
+	for (i = 0; i < len; i++)
+		CRC32C(crc32c, buf[i]);
+	crc32c = ~crc32c;
+	byte0  = crc32c & 0xff;
+	byte1  = (crc32c>>8) & 0xff;
+	byte2  = (crc32c>>16) & 0xff;
+	byte3  = (crc32c>>24) & 0xff;
+	crc32c = ((byte0 << 24) | (byte1 << 16) | (byte2 << 8) | byte3);
+	return htonl(crc32c);
+}
+
+/*
  * Subtract 2 timeval structs:  out = out - in.
  * Out is assumed to be within about LONG_MAX seconds of in.
  */