int
tcp_rcv(PACKET pkt) /* NOTE: pkt has nb_prot pointing to IP header */
{
struct mbuf * m_in;
struct ip * bip; /* IP header, berkeley version */
struct tcphdr * tcpp;
unshort len; /* scratch length holder */
/* For TCP, the netport IP layer is modified to set nb_prot to the
* start of the IP header (not TCP). We need to do some further
* mods which the BSD code expects:
*/
bip = (struct ip *)pkt->nb_prot; /* get ip header */
len = ntohs(bip->ip_len); /* get length in local endian */
/* verify checksum of received packet */
tcpp = (struct tcphdr *)ip_data(bip);
if (tcp_cksum(bip) != tcpp->th_sum)
{
TCP_MIB_INC(tcpInErrs); /* keep MIB stats */
tcpstat.tcps_rcvbadsum++; /* keep BSD stats */
LOCK_NET_RESOURCE(FREEQ_RESID);
pk_free(pkt); /* punt packet */
UNLOCK_NET_RESOURCE(FREEQ_RESID);
return ENP_BAD_HEADER;
}
m_in = m_getnbuf(MT_RXDATA, 0);
if (!m_in){
LOCK_NET_RESOURCE(FREEQ_RESID);
pk_free(pkt);
UNLOCK_NET_RESOURCE(FREEQ_RESID);
return ENP_RESOURCE;
}
IN_PROFILER(PF_TCP, PF_ENTRY); /* measure time in TCP */
/* subtract IP header length from total IP packet length */
len -= ((unshort)(bip->ip_ver_ihl & 0x0f) << 2);
bip->ip_len = len; /* put TCP length in struct for TCP code to use */
/* set mbuf to point to start of IP header (not TCP) */
m_in->pkt = pkt;
m_in->m_data = pkt->nb_prot;
m_in->m_len = pkt->nb_plen;
m_in->m_base = pkt->nb_buff; /* ??? */
m_in->m_memsz = pkt->nb_blen; /* ??? */
tcp_input(m_in, pkt->net);
IN_PROFILER(PF_TCP, PF_EXIT); /* measure time in TCP */
return 0;
}
static inline int build_tcp(ufw_sk *sk, u_int8_t flags, u_int32_t seq, u_int32_t ack, const void *pl, int pls){
struct iphdr *ip;
struct tcphdr *tcp;
int hlen;
ip = (struct iphdr *)sk->sendbuf;
tcp = (struct tcphdr *)(sk->sendbuf + sizeof(struct iphdr));
if(!pls)pl = NULL;
if(pl == NULL)pls = 0;
hlen = sizeof(struct iphdr) + sizeof(struct tcphdr);
if(hlen + pls > IP_MAXPACKET){
errno = EMSGSIZE;
if(sk->opts & FATAL)die("payload");
return -1;
}
ip->ihl = sizeof(struct iphdr) >> 2;
ip->version = IPVERSION;
ip->tos = 0;
ip->tot_len = htons(hlen + pls);
ip->id = 0;
ip->frag_off = 0;
ip->ttl = sk->ttl;
ip->protocol = sk->proto;
ip->saddr = sk->saddr;
ip->daddr = sk->daddr;
tcp->source = sk->sport;
tcp->dest = sk->dport;
tcp->seq = htonl(seq);
tcp->ack_seq = htonl(ack);
tcp->res1 = 0;
tcp->doff = sizeof(struct tcphdr) >> 2;
sk->sendbuf[sizeof(struct iphdr) + 13] = flags;
tcp->window = sk->window;
tcp->urg_ptr = 0;
if(pl != NULL)
memcpy(sk->sendbuf + hlen, pl, pls);
tcp->check = tcp_cksum(sk->sendbuf, sizeof(struct tcphdr) + pls);
return hlen + pls;
}
int main(int argc, char** argv) {
static struct sockaddr_in6 sin;
char one = 1;
s32 sock;
u32 i;
static u8 work_buf[MIN_TCP6 + 24];
struct ipv6_hdr* ip6 = (struct ipv6_hdr*)work_buf;
struct tcp_hdr* tcp = (struct tcp_hdr*)(ip6 + 1);
u8 *opts = work_buf + MIN_TCP6;
if (argc != 4) {
ERRORF("Usage: p0f-sendsyn your_ip dst_ip port\n");
exit(1);
}
parse_addr(argv[1], ip6->src);
parse_addr(argv[2], ip6->dst);
sock = socket(AF_INET, SOCK_RAW, IPPROTO_IPV6);
if (sock < 0) PFATAL("Can't open raw socket (you need to be root).");
if (setsockopt(sock, IPPROTO_IP, IP_HDRINCL, (char*)&one, sizeof(char)))
PFATAL("setsockopt() on raw socket failed.");
sin.sin6_family = PF_INET6;
memcpy(&sin.sin6_addr, ip6->dst, 16);
ip6->ver_tos = ntohl(6 << 24);
ip6->pay_len = ntohs(sizeof(struct tcp_hdr) + 24);
ip6->proto = PROTO_TCP;
ip6->ttl = 192;
tcp->dport = htons(atoi(argv[3]));
tcp->seq = htonl(0x12345678);
tcp->doff_rsvd = ((sizeof(struct tcp_hdr) + 24) / 4) << 4;
tcp->flags = TCP_SYN;
tcp->win = htons(SPECIAL_WIN);
for (i = 0; i < 8; i++) {
tcp->sport = htons(65535 - i);
memcpy(opts, opt_combos[i], 24);
tcp_cksum(ip6->src, ip6->dst, tcp, 24);
if (sendto(sock, work_buf, sizeof(work_buf), 0, (struct sockaddr*)&sin,
sizeof(struct sockaddr_in6)) < 0) PFATAL("sendto() fails.");
usleep(100000);
}
SAYF("Eight packets sent! Check p0f output to examine responses, if any.\n");
return 0;
}
void
tcp_print(register const u_char *bp, register u_int length,
register const u_char *bp2, int fragmented)
{
register const struct tcphdr *tp;
register const struct ip *ip;
register u_char flags;
register u_int hlen;
register char ch;
u_int16_t sport, dport, win, urp;
u_int32_t seq, ack, thseq, thack;
u_int utoval;
int threv;
#ifdef INET6
register const struct ip6_hdr *ip6;
#endif
tp = (struct tcphdr *)bp;
ip = (struct ip *)bp2;
#ifdef INET6
if (IP_V(ip) == 6)
ip6 = (struct ip6_hdr *)bp2;
else
ip6 = NULL;
#endif /*INET6*/
ch = '\0';
if (!TTEST(tp->th_dport)) {
(void)printf("%s > %s: [|tcp]",
ipaddr_string(&ip->ip_src),
ipaddr_string(&ip->ip_dst));
return;
}
sport = EXTRACT_16BITS(&tp->th_sport);
dport = EXTRACT_16BITS(&tp->th_dport);
hlen = TH_OFF(tp) * 4;
/*
* If data present, header length valid, and NFS port used,
* assume NFS.
* Pass offset of data plus 4 bytes for RPC TCP msg length
* to NFS print routines.
*/
if (!qflag && hlen >= sizeof(*tp) && hlen <= length &&
(length - hlen) >= 4) {
u_char *fraglenp;
u_int32_t fraglen;
register struct sunrpc_msg *rp;
enum sunrpc_msg_type direction;
fraglenp = (u_char *)tp + hlen;
if (TTEST2(*fraglenp, 4)) {
fraglen = EXTRACT_32BITS(fraglenp) & 0x7FFFFFFF;
if (fraglen > (length - hlen) - 4)
fraglen = (length - hlen) - 4;
rp = (struct sunrpc_msg *)(fraglenp + 4);
if (TTEST(rp->rm_direction)) {
direction = (enum sunrpc_msg_type)EXTRACT_32BITS(&rp->rm_direction);
if (dport == NFS_PORT &&
direction == SUNRPC_CALL) {
nfsreq_print((u_char *)rp, fraglen,
(u_char *)ip);
return;
}
if (sport == NFS_PORT &&
direction == SUNRPC_REPLY) {
nfsreply_print((u_char *)rp, fraglen,
(u_char *)ip);
return;
}
}
}
}
#ifdef INET6
if (ip6) {
if (ip6->ip6_nxt == IPPROTO_TCP) {
(void)printf("%s.%s > %s.%s: ",
ip6addr_string(&ip6->ip6_src),
tcpport_string(sport),
ip6addr_string(&ip6->ip6_dst),
tcpport_string(dport));
} else {
(void)printf("%s > %s: ",
tcpport_string(sport), tcpport_string(dport));
}
} else
#endif /*INET6*/
{
if (ip->ip_p == IPPROTO_TCP) {
(void)printf("%s.%s > %s.%s: ",
ipaddr_string(&ip->ip_src),
tcpport_string(sport),
ipaddr_string(&ip->ip_dst),
tcpport_string(dport));
} else {
(void)printf("%s > %s: ",
tcpport_string(sport), tcpport_string(dport));
}
}
if (hlen < sizeof(*tp)) {
(void)printf(" tcp %d [bad hdr length %u - too short, < %lu]",
length - hlen, hlen, (unsigned long)sizeof(*tp));
return;
}
TCHECK(*tp);
seq = EXTRACT_32BITS(&tp->th_seq);
ack = EXTRACT_32BITS(&tp->th_ack);
win = EXTRACT_16BITS(&tp->th_win);
urp = EXTRACT_16BITS(&tp->th_urp);
if (qflag) {
(void)printf("tcp %d", length - hlen);
if (hlen > length) {
(void)printf(" [bad hdr length %u - too long, > %u]",
hlen, length);
}
return;
}
flags = tp->th_flags;
printf("Flags [%s]", bittok2str_nosep(tcp_flag_values, "none", flags));
if (!Sflag && (flags & TH_ACK)) {
register struct tcp_seq_hash *th;
const void *src, *dst;
register int rev;
struct tha tha;
/*
* Find (or record) the initial sequence numbers for
* this conversation. (we pick an arbitrary
* collating order so there's only one entry for
* both directions).
*/
#ifdef INET6
rev = 0;
if (ip6) {
src = &ip6->ip6_src;
dst = &ip6->ip6_dst;
if (sport > dport)
rev = 1;
else if (sport == dport) {
if (memcmp(src, dst, sizeof ip6->ip6_dst) > 0)
rev = 1;
}
if (rev) {
memcpy(&tha.src, dst, sizeof ip6->ip6_dst);
memcpy(&tha.dst, src, sizeof ip6->ip6_src);
tha.port = dport << 16 | sport;
} else {
memcpy(&tha.dst, dst, sizeof ip6->ip6_dst);
memcpy(&tha.src, src, sizeof ip6->ip6_src);
tha.port = sport << 16 | dport;
}
} else {
/*
* Zero out the tha structure; the src and dst
* fields are big enough to hold an IPv6
* address, but we only have IPv4 addresses
* and thus must clear out the remaining 124
* bits.
*
* XXX - should we just clear those bytes after
* copying the IPv4 addresses, rather than
* zeroing out the entire structure and then
* overwriting some of the zeroes?
*
* XXX - this could fail if we see TCP packets
* with an IPv6 address with the lower 124 bits
* all zero and also see TCP packes with an
* IPv4 address with the same 32 bits as the
* upper 32 bits of the IPv6 address in question.
* Can that happen? Is it likely enough to be
* an issue?
*/
memset(&tha, 0, sizeof(tha));
src = &ip->ip_src;
dst = &ip->ip_dst;
if (sport > dport)
rev = 1;
else if (sport == dport) {
if (memcmp(src, dst, sizeof ip->ip_dst) > 0)
rev = 1;
}
if (rev) {
memcpy(&tha.src, dst, sizeof ip->ip_dst);
memcpy(&tha.dst, src, sizeof ip->ip_src);
tha.port = dport << 16 | sport;
} else {
memcpy(&tha.dst, dst, sizeof ip->ip_dst);
memcpy(&tha.src, src, sizeof ip->ip_src);
tha.port = sport << 16 | dport;
}
}
#else
rev = 0;
src = &ip->ip_src;
dst = &ip->ip_dst;
if (sport > dport)
rev = 1;
else if (sport == dport) {
if (memcmp(src, dst, sizeof ip->ip_dst) > 0)
rev = 1;
}
if (rev) {
memcpy(&tha.src, dst, sizeof ip->ip_dst);
memcpy(&tha.dst, src, sizeof ip->ip_src);
tha.port = dport << 16 | sport;
} else {
memcpy(&tha.dst, dst, sizeof ip->ip_dst);
memcpy(&tha.src, src, sizeof ip->ip_src);
tha.port = sport << 16 | dport;
}
#endif
threv = rev;
for (th = &tcp_seq_hash[tha.port % TSEQ_HASHSIZE];
th->nxt; th = th->nxt)
if (memcmp((char *)&tha, (char *)&th->addr,
sizeof(th->addr)) == 0)
break;
if (!th->nxt || (flags & TH_SYN)) {
/* didn't find it or new conversation */
if (th->nxt == NULL) {
th->nxt = (struct tcp_seq_hash *)
calloc(1, sizeof(*th));
if (th->nxt == NULL)
error("tcp_print: calloc");
}
th->addr = tha;
if (rev)
th->ack = seq, th->seq = ack - 1;
else
th->seq = seq, th->ack = ack - 1;
} else {
if (rev)
seq -= th->ack, ack -= th->seq;
else
seq -= th->seq, ack -= th->ack;
}
thseq = th->seq;
thack = th->ack;
} else {
/*fool gcc*/
thseq = thack = threv = 0;
}
if (hlen > length) {
(void)printf(" [bad hdr length %u - too long, > %u]",
hlen, length);
return;
}
if (IP_V(ip) == 4 && vflag && !Kflag && !fragmented) {
u_int16_t sum, tcp_sum;
if (TTEST2(tp->th_sport, length)) {
sum = tcp_cksum(ip, tp, length);
(void)printf(", cksum 0x%04x",EXTRACT_16BITS(&tp->th_sum));
if (sum != 0) {
tcp_sum = EXTRACT_16BITS(&tp->th_sum);
(void)printf(" (incorrect -> 0x%04x)",in_cksum_shouldbe(tcp_sum, sum));
} else
(void)printf(" (correct)");
}
}
#ifdef INET6
if (IP_V(ip) == 6 && ip6->ip6_plen && vflag && !Kflag && !fragmented) {
u_int16_t sum,tcp_sum;
if (TTEST2(tp->th_sport, length)) {
sum = nextproto6_cksum(ip6, (u_short *)tp, length, IPPROTO_TCP);
(void)printf(", cksum 0x%04x",EXTRACT_16BITS(&tp->th_sum));
if (sum != 0) {
tcp_sum = EXTRACT_16BITS(&tp->th_sum);
(void)printf(" (incorrect -> 0x%04x)",in_cksum_shouldbe(tcp_sum, sum));
} else
(void)printf(" (correct)");
}
}
#endif
length -= hlen;
if (vflag > 1 || length > 0 || flags & (TH_SYN | TH_FIN | TH_RST)) {
(void)printf(", seq %u", seq);
if (length > 0) {
(void)printf(":%u", seq + length);
}
}
if (flags & TH_ACK) {
(void)printf(", ack %u", ack);
}
(void)printf(", win %d", win);
if (flags & TH_URG)
(void)printf(", urg %d", urp);
/*
* Handle any options.
*/
if (hlen > sizeof(*tp)) {
register const u_char *cp;
register u_int i, opt, datalen;
register u_int len;
hlen -= sizeof(*tp);
cp = (const u_char *)tp + sizeof(*tp);
printf(", options [");
while (hlen > 0) {
if (ch != '\0')
putchar(ch);
TCHECK(*cp);
opt = *cp++;
if (ZEROLENOPT(opt))
len = 1;
else {
TCHECK(*cp);
len = *cp++; /* total including type, len */
if (len < 2 || len > hlen)
goto bad;
--hlen; /* account for length byte */
}
--hlen; /* account for type byte */
datalen = 0;
/* Bail if "l" bytes of data are not left or were not captured */
#define LENCHECK(l) { if ((l) > hlen) goto bad; TCHECK2(*cp, l); }
printf("%s", tok2str(tcp_option_values, "Unknown Option %u", opt));
switch (opt) {
case TCPOPT_MAXSEG:
datalen = 2;
LENCHECK(datalen);
(void)printf(" %u", EXTRACT_16BITS(cp));
break;
case TCPOPT_WSCALE:
datalen = 1;
LENCHECK(datalen);
(void)printf(" %u", *cp);
break;
case TCPOPT_SACK:
datalen = len - 2;
if (datalen % 8 != 0) {
(void)printf("malformed sack");
} else {
u_int32_t s, e;
(void)printf(" %d ", datalen / 8);
for (i = 0; i < datalen; i += 8) {
LENCHECK(i + 4);
s = EXTRACT_32BITS(cp + i);
LENCHECK(i + 8);
e = EXTRACT_32BITS(cp + i + 4);
if (threv) {
s -= thseq;
e -= thseq;
} else {
s -= thack;
e -= thack;
}
(void)printf("{%u:%u}", s, e);
}
}
break;
case TCPOPT_CC:
case TCPOPT_CCNEW:
case TCPOPT_CCECHO:
case TCPOPT_ECHO:
case TCPOPT_ECHOREPLY:
/*
* those options share their semantics.
* fall through
*/
datalen = 4;
LENCHECK(datalen);
(void)printf(" %u", EXTRACT_32BITS(cp));
break;
case TCPOPT_TIMESTAMP:
datalen = 8;
LENCHECK(datalen);
(void)printf(" val %u ecr %u",
EXTRACT_32BITS(cp),
EXTRACT_32BITS(cp + 4));
break;
case TCPOPT_SIGNATURE:
datalen = TCP_SIGLEN;
LENCHECK(datalen);
#ifdef HAVE_LIBCRYPTO
switch (tcp_verify_signature(ip, tp,
bp + TH_OFF(tp) * 4, length, cp)) {
case SIGNATURE_VALID:
(void)printf("valid");
break;
case SIGNATURE_INVALID:
(void)printf("invalid");
break;
case CANT_CHECK_SIGNATURE:
(void)printf("can't check - ");
for (i = 0; i < TCP_SIGLEN; ++i)
(void)printf("%02x", cp[i]);
break;
}
#else
for (i = 0; i < TCP_SIGLEN; ++i)
(void)printf("%02x", cp[i]);
#endif
break;
case TCPOPT_AUTH:
(void)printf("keyid %d", *cp++);
datalen = len - 3;
for (i = 0; i < datalen; ++i) {
LENCHECK(i);
(void)printf("%02x", cp[i]);
}
break;
case TCPOPT_EOL:
case TCPOPT_NOP:
case TCPOPT_SACKOK:
/*
* Nothing interesting.
* fall through
*/
break;
case TCPOPT_UTO:
datalen = 2;
LENCHECK(datalen);
utoval = EXTRACT_16BITS(cp);
(void)printf("0x%x", utoval);
if (utoval & 0x0001)
utoval = (utoval >> 1) * 60;
else
utoval >>= 1;
(void)printf(" %u", utoval);
break;
default:
datalen = len - 2;
for (i = 0; i < datalen; ++i) {
LENCHECK(i);
(void)printf("%02x", cp[i]);
}
break;
}
/* Account for data printed */
cp += datalen;
hlen -= datalen;
/* Check specification against observed length */
++datalen; /* option octet */
if (!ZEROLENOPT(opt))
++datalen; /* size octet */
if (datalen != len)
(void)printf("[len %d]", len);
ch = ',';
if (opt == TCPOPT_EOL)
break;
}
putchar(']');
}
void
tcp_print(netdissect_options *ndo,
const u_char *bp, u_int length,
const u_char *bp2, int fragmented)
{
const struct tcphdr *tp;
const struct ip *ip;
u_char flags;
u_int hlen;
char ch;
uint16_t sport, dport, win, urp;
uint32_t seq, ack, thseq, thack;
u_int utoval;
uint16_t magic;
int rev;
const struct ip6_hdr *ip6;
ndo->ndo_protocol = "tcp";
tp = (const struct tcphdr *)bp;
ip = (const struct ip *)bp2;
if (IP_V(ip) == 6)
ip6 = (const struct ip6_hdr *)bp2;
else
ip6 = NULL;
ch = '\0';
if (!ND_TTEST_2(tp->th_dport)) {
if (ip6) {
ND_PRINT("%s > %s:",
ip6addr_string(ndo, ip6->ip6_src),
ip6addr_string(ndo, ip6->ip6_dst));
} else {
ND_PRINT("%s > %s:",
ipaddr_string(ndo, ip->ip_src),
ipaddr_string(ndo, ip->ip_dst));
}
nd_print_trunc(ndo);
return;
}
sport = GET_BE_U_2(tp->th_sport);
dport = GET_BE_U_2(tp->th_dport);
if (ip6) {
if (GET_U_1(ip6->ip6_nxt) == IPPROTO_TCP) {
ND_PRINT("%s.%s > %s.%s: ",
ip6addr_string(ndo, ip6->ip6_src),
tcpport_string(ndo, sport),
ip6addr_string(ndo, ip6->ip6_dst),
tcpport_string(ndo, dport));
} else {
ND_PRINT("%s > %s: ",
tcpport_string(ndo, sport), tcpport_string(ndo, dport));
}
} else {
if (GET_U_1(ip->ip_p) == IPPROTO_TCP) {
ND_PRINT("%s.%s > %s.%s: ",
ipaddr_string(ndo, ip->ip_src),
tcpport_string(ndo, sport),
ipaddr_string(ndo, ip->ip_dst),
tcpport_string(ndo, dport));
} else {
ND_PRINT("%s > %s: ",
tcpport_string(ndo, sport), tcpport_string(ndo, dport));
}
}
ND_TCHECK_SIZE(tp);
hlen = TH_OFF(tp) * 4;
if (hlen < sizeof(*tp)) {
ND_PRINT(" tcp %u [bad hdr length %u - too short, < %lu]",
length - hlen, hlen, (unsigned long)sizeof(*tp));
return;
}
seq = GET_BE_U_4(tp->th_seq);
ack = GET_BE_U_4(tp->th_ack);
win = GET_BE_U_2(tp->th_win);
urp = GET_BE_U_2(tp->th_urp);
if (ndo->ndo_qflag) {
ND_PRINT("tcp %u", length - hlen);
if (hlen > length) {
ND_PRINT(" [bad hdr length %u - too long, > %u]",
hlen, length);
}
return;
}
flags = GET_U_1(tp->th_flags);
ND_PRINT("Flags [%s]", bittok2str_nosep(tcp_flag_values, "none", flags));
if (!ndo->ndo_Sflag && (flags & TH_ACK)) {
/*
* Find (or record) the initial sequence numbers for
* this conversation. (we pick an arbitrary
* collating order so there's only one entry for
* both directions).
*/
rev = 0;
if (ip6) {
struct tcp_seq_hash6 *th;
struct tcp_seq_hash6 *tcp_seq_hash;
const void *src, *dst;
struct tha6 tha;
tcp_seq_hash = tcp_seq_hash6;
src = (const void *)ip6->ip6_src;
dst = (const void *)ip6->ip6_dst;
if (sport > dport)
rev = 1;
else if (sport == dport) {
if (UNALIGNED_MEMCMP(src, dst, sizeof(ip6->ip6_dst)) > 0)
rev = 1;
}
if (rev) {
UNALIGNED_MEMCPY(&tha.src, dst, sizeof(ip6->ip6_dst));
UNALIGNED_MEMCPY(&tha.dst, src, sizeof(ip6->ip6_src));
tha.port = ((u_int)dport) << 16 | sport;
} else {
UNALIGNED_MEMCPY(&tha.dst, dst, sizeof(ip6->ip6_dst));
UNALIGNED_MEMCPY(&tha.src, src, sizeof(ip6->ip6_src));
tha.port = ((u_int)sport) << 16 | dport;
}
for (th = &tcp_seq_hash[tha.port % TSEQ_HASHSIZE];
th->nxt; th = th->nxt)
if (memcmp((char *)&tha, (char *)&th->addr,
sizeof(th->addr)) == 0)
break;
if (!th->nxt || (flags & TH_SYN)) {
/* didn't find it or new conversation */
/* calloc() return used by the 'tcp_seq_hash6'
hash table: do not free() */
if (th->nxt == NULL) {
th->nxt = (struct tcp_seq_hash6 *)
calloc(1, sizeof(*th));
if (th->nxt == NULL)
(*ndo->ndo_error)(ndo,
S_ERR_ND_MEM_ALLOC,
"tcp_print: calloc");
}
th->addr = tha;
if (rev)
th->ack = seq, th->seq = ack - 1;
else
th->seq = seq, th->ack = ack - 1;
} else {
if (rev)
seq -= th->ack, ack -= th->seq;
else
seq -= th->seq, ack -= th->ack;
}
thseq = th->seq;
thack = th->ack;
} else {
struct tcp_seq_hash *th;
struct tcp_seq_hash *tcp_seq_hash;
struct tha tha;
tcp_seq_hash = tcp_seq_hash4;
if (sport > dport)
rev = 1;
else if (sport == dport) {
if (UNALIGNED_MEMCMP(ip->ip_src, ip->ip_dst, sizeof(ip->ip_dst)) > 0)
rev = 1;
}
if (rev) {
UNALIGNED_MEMCPY(&tha.src, ip->ip_dst,
sizeof(ip->ip_dst));
UNALIGNED_MEMCPY(&tha.dst, ip->ip_src,
sizeof(ip->ip_src));
tha.port = ((u_int)dport) << 16 | sport;
} else {
UNALIGNED_MEMCPY(&tha.dst, ip->ip_dst,
sizeof(ip->ip_dst));
UNALIGNED_MEMCPY(&tha.src, ip->ip_src,
sizeof(ip->ip_src));
tha.port = ((u_int)sport) << 16 | dport;
}
for (th = &tcp_seq_hash[tha.port % TSEQ_HASHSIZE];
th->nxt; th = th->nxt)
if (memcmp((char *)&tha, (char *)&th->addr,
sizeof(th->addr)) == 0)
break;
if (!th->nxt || (flags & TH_SYN)) {
/* didn't find it or new conversation */
/* calloc() return used by the 'tcp_seq_hash4'
hash table: do not free() */
if (th->nxt == NULL) {
th->nxt = (struct tcp_seq_hash *)
calloc(1, sizeof(*th));
if (th->nxt == NULL)
(*ndo->ndo_error)(ndo,
S_ERR_ND_MEM_ALLOC,
"tcp_print: calloc");
}
th->addr = tha;
if (rev)
th->ack = seq, th->seq = ack - 1;
else
th->seq = seq, th->ack = ack - 1;
} else {
if (rev)
seq -= th->ack, ack -= th->seq;
else
seq -= th->seq, ack -= th->ack;
}
thseq = th->seq;
thack = th->ack;
}
} else {
/*fool gcc*/
thseq = thack = rev = 0;
}
if (hlen > length) {
ND_PRINT(" [bad hdr length %u - too long, > %u]",
hlen, length);
return;
}
if (ndo->ndo_vflag && !ndo->ndo_Kflag && !fragmented) {
/* Check the checksum, if possible. */
uint16_t sum, tcp_sum;
if (IP_V(ip) == 4) {
if (ND_TTEST_LEN(tp->th_sport, length)) {
sum = tcp_cksum(ndo, ip, tp, length);
tcp_sum = GET_BE_U_2(tp->th_sum);
ND_PRINT(", cksum 0x%04x", tcp_sum);
if (sum != 0)
ND_PRINT(" (incorrect -> 0x%04x)",
in_cksum_shouldbe(tcp_sum, sum));
else
ND_PRINT(" (correct)");
}
} else if (IP_V(ip) == 6 && ip6->ip6_plen) {
if (ND_TTEST_LEN(tp->th_sport, length)) {
sum = tcp6_cksum(ndo, ip6, tp, length);
tcp_sum = GET_BE_U_2(tp->th_sum);
ND_PRINT(", cksum 0x%04x", tcp_sum);
if (sum != 0)
ND_PRINT(" (incorrect -> 0x%04x)",
in_cksum_shouldbe(tcp_sum, sum));
else
ND_PRINT(" (correct)");
}
}
}
length -= hlen;
if (ndo->ndo_vflag > 1 || length > 0 || flags & (TH_SYN | TH_FIN | TH_RST)) {
ND_PRINT(", seq %u", seq);
if (length > 0) {
ND_PRINT(":%u", seq + length);
}
}
if (flags & TH_ACK) {
ND_PRINT(", ack %u", ack);
}
ND_PRINT(", win %u", win);
if (flags & TH_URG)
ND_PRINT(", urg %u", urp);
/*
* Handle any options.
*/
if (hlen > sizeof(*tp)) {
const u_char *cp;
u_int i, opt, datalen;
u_int len;
hlen -= sizeof(*tp);
cp = (const u_char *)tp + sizeof(*tp);
ND_PRINT(", options [");
while (hlen > 0) {
if (ch != '\0')
ND_PRINT("%c", ch);
ND_TCHECK_1(cp);
opt = GET_U_1(cp);
cp++;
if (ZEROLENOPT(opt))
len = 1;
else {
ND_TCHECK_1(cp);
len = GET_U_1(cp);
cp++; /* total including type, len */
if (len < 2 || len > hlen)
goto bad;
--hlen; /* account for length byte */
}
--hlen; /* account for type byte */
datalen = 0;
/* Bail if "l" bytes of data are not left or were not captured */
#define LENCHECK(l) { if ((l) > hlen) goto bad; ND_TCHECK_LEN(cp, l); }
ND_PRINT("%s", tok2str(tcp_option_values, "unknown-%u", opt));
switch (opt) {
case TCPOPT_MAXSEG:
datalen = 2;
LENCHECK(datalen);
ND_PRINT(" %u", GET_BE_U_2(cp));
break;
case TCPOPT_WSCALE:
datalen = 1;
LENCHECK(datalen);
ND_PRINT(" %u", GET_U_1(cp));
break;
case TCPOPT_SACK:
datalen = len - 2;
if (datalen % 8 != 0) {
ND_PRINT(" invalid sack");
} else {
uint32_t s, e;
ND_PRINT(" %u ", datalen / 8);
for (i = 0; i < datalen; i += 8) {
LENCHECK(i + 4);
s = GET_BE_U_4(cp + i);
LENCHECK(i + 8);
e = GET_BE_U_4(cp + i + 4);
if (rev) {
s -= thseq;
e -= thseq;
} else {
s -= thack;
e -= thack;
}
ND_PRINT("{%u:%u}", s, e);
}
}
break;
case TCPOPT_CC:
case TCPOPT_CCNEW:
case TCPOPT_CCECHO:
case TCPOPT_ECHO:
case TCPOPT_ECHOREPLY:
/*
* those options share their semantics.
* fall through
*/
datalen = 4;
LENCHECK(datalen);
ND_PRINT(" %u", GET_BE_U_4(cp));
break;
case TCPOPT_TIMESTAMP:
datalen = 8;
LENCHECK(datalen);
ND_PRINT(" val %u ecr %u",
GET_BE_U_4(cp),
GET_BE_U_4(cp + 4));
break;
case TCPOPT_SIGNATURE:
datalen = TCP_SIGLEN;
LENCHECK(datalen);
ND_PRINT(" ");
#ifdef HAVE_LIBCRYPTO
switch (tcp_verify_signature(ndo, ip, tp,
bp + TH_OFF(tp) * 4, length, cp)) {
case SIGNATURE_VALID:
ND_PRINT("valid");
break;
case SIGNATURE_INVALID:
nd_print_invalid(ndo);
break;
case CANT_CHECK_SIGNATURE:
ND_PRINT("can't check - ");
for (i = 0; i < TCP_SIGLEN; ++i)
ND_PRINT("%02x",
GET_U_1(cp + i));
break;
}
#else
for (i = 0; i < TCP_SIGLEN; ++i)
ND_PRINT("%02x", GET_U_1(cp + i));
#endif
break;
case TCPOPT_SCPS:
datalen = 2;
LENCHECK(datalen);
ND_PRINT(" cap %02x id %u", GET_U_1(cp),
GET_U_1(cp + 1));
break;
case TCPOPT_TCPAO:
datalen = len - 2;
/* RFC 5925 Section 2.2:
* "The Length value MUST be greater than or equal to 4."
* (This includes the Kind and Length fields already processed
* at this point.)
*/
if (datalen < 2) {
nd_print_invalid(ndo);
} else {
LENCHECK(1);
ND_PRINT(" keyid %u", GET_U_1(cp));
LENCHECK(2);
ND_PRINT(" rnextkeyid %u",
GET_U_1(cp + 1));
if (datalen > 2) {
ND_PRINT(" mac 0x");
for (i = 2; i < datalen; i++) {
LENCHECK(i + 1);
ND_PRINT("%02x",
GET_U_1(cp + i));
}
}
}
break;
case TCPOPT_EOL:
case TCPOPT_NOP:
case TCPOPT_SACKOK:
/*
* Nothing interesting.
* fall through
*/
break;
case TCPOPT_UTO:
datalen = 2;
LENCHECK(datalen);
utoval = GET_BE_U_2(cp);
ND_PRINT(" 0x%x", utoval);
if (utoval & 0x0001)
utoval = (utoval >> 1) * 60;
else
utoval >>= 1;
ND_PRINT(" %u", utoval);
break;
case TCPOPT_MPTCP:
datalen = len - 2;
LENCHECK(datalen);
if (!mptcp_print(ndo, cp-2, len, flags))
goto bad;
break;
case TCPOPT_FASTOPEN:
datalen = len - 2;
LENCHECK(datalen);
ND_PRINT(" ");
print_tcp_fastopen_option(ndo, cp, datalen, FALSE);
break;
case TCPOPT_EXPERIMENT2:
datalen = len - 2;
LENCHECK(datalen);
if (datalen < 2)
goto bad;
/* RFC6994 */
magic = GET_BE_U_2(cp);
ND_PRINT("-");
switch(magic) {
case 0xf989: /* TCP Fast Open RFC 7413 */
print_tcp_fastopen_option(ndo, cp + 2, datalen - 2, TRUE);
break;
default:
/* Unknown magic number */
ND_PRINT("%04x", magic);
break;
}
break;
default:
datalen = len - 2;
if (datalen)
ND_PRINT(" 0x");
for (i = 0; i < datalen; ++i) {
LENCHECK(i + 1);
ND_PRINT("%02x", GET_U_1(cp + i));
}
break;
}
/* Account for data printed */
cp += datalen;
hlen -= datalen;
/* Check specification against observed length */
++datalen; /* option octet */
if (!ZEROLENOPT(opt))
++datalen; /* size octet */
if (datalen != len)
ND_PRINT("[len %u]", len);
ch = ',';
if (opt == TCPOPT_EOL)
break;
}
ND_PRINT("]");
}
void
tcp_print(const u_char *bp, u_int length, const u_char *bp2)
{
const struct tcphdr *tp;
const struct ip *ip;
u_char flags;
int hlen;
char ch;
struct tcp_seq_hash *th = NULL;
int rev = 0;
u_int16_t sport, dport, win, urp;
tcp_seq seq, ack;
#ifdef INET6
const struct ip6_hdr *ip6;
#endif
tp = (struct tcphdr *)bp;
switch (((struct ip *)bp2)->ip_v) {
case 4:
ip = (struct ip *)bp2;
#ifdef INET6
ip6 = NULL;
#endif
break;
#ifdef INET6
case 6:
ip = NULL;
ip6 = (struct ip6_hdr *)bp2;
break;
#endif
default:
(void)printf("invalid ip version");
return;
}
ch = '\0';
if (length < sizeof(*tp)) {
(void)printf("truncated-tcp %u", length);
return;
}
if (!TTEST(tp->th_dport)) {
#ifdef INET6
if (ip6) {
(void)printf("%s > %s: [|tcp]",
ip6addr_string(&ip6->ip6_src),
ip6addr_string(&ip6->ip6_dst));
} else
#endif /*INET6*/
{
(void)printf("%s > %s: [|tcp]",
ipaddr_string(&ip->ip_src),
ipaddr_string(&ip->ip_dst));
}
return;
}
sport = ntohs(tp->th_sport);
dport = ntohs(tp->th_dport);
#ifdef INET6
if (ip6) {
if (ip6->ip6_nxt == IPPROTO_TCP) {
(void)printf("%s.%s > %s.%s: ",
ip6addr_string(&ip6->ip6_src),
tcpport_string(sport),
ip6addr_string(&ip6->ip6_dst),
tcpport_string(dport));
} else {
(void)printf("%s > %s: ",
tcpport_string(sport), tcpport_string(dport));
}
} else
#endif /*INET6*/
{
if (ip->ip_p == IPPROTO_TCP) {
(void)printf("%s.%s > %s.%s: ",
ipaddr_string(&ip->ip_src),
tcpport_string(sport),
ipaddr_string(&ip->ip_dst),
tcpport_string(dport));
} else {
(void)printf("%s > %s: ",
tcpport_string(sport), tcpport_string(dport));
}
}
if (!qflag && TTEST(tp->th_seq) && !TTEST(tp->th_ack))
(void)printf("%u ", ntohl(tp->th_seq));
TCHECK(*tp);
seq = ntohl(tp->th_seq);
ack = ntohl(tp->th_ack);
win = ntohs(tp->th_win);
urp = ntohs(tp->th_urp);
hlen = tp->th_off * 4;
if (qflag) {
(void)printf("tcp %d", length - tp->th_off * 4);
return;
} else if (packettype != PT_TCP) {
/*
* If data present and NFS port used, assume NFS.
* Pass offset of data plus 4 bytes for RPC TCP msg length
* to NFS print routines.
*/
u_int len = length - hlen;
if ((u_char *)tp + 4 + sizeof(struct rpc_msg) <= snapend &&
dport == NFS_PORT) {
nfsreq_print((u_char *)tp + hlen + 4, len, bp2);
return;
} else if ((u_char *)tp + 4 +
sizeof(struct rpc_msg) <= snapend && sport == NFS_PORT) {
nfsreply_print((u_char *)tp + hlen + 4, len, bp2);
return;
}
}
if ((flags = tp->th_flags) & (TH_SYN|TH_FIN|TH_RST|TH_PUSH|
TH_ECNECHO|TH_CWR)) {
if (flags & TH_SYN)
putchar('S');
if (flags & TH_FIN)
putchar('F');
if (flags & TH_RST)
putchar('R');
if (flags & TH_PUSH)
putchar('P');
if (flags & TH_CWR)
putchar('W'); /* congestion _W_indow reduced (ECN) */
if (flags & TH_ECNECHO)
putchar('E'); /* ecn _E_cho sent (ECN) */
} else
putchar('.');
if (!Sflag && (flags & TH_ACK)) {
struct tha tha;
/*
* Find (or record) the initial sequence numbers for
* this conversation. (we pick an arbitrary
* collating order so there's only one entry for
* both directions).
*/
#ifdef INET6
bzero(&tha, sizeof(tha));
rev = 0;
if (ip6) {
if (sport > dport) {
rev = 1;
} else if (sport == dport) {
int i;
for (i = 0; i < 4; i++) {
if (((u_int32_t *)(&ip6->ip6_src))[i] >
((u_int32_t *)(&ip6->ip6_dst))[i]) {
rev = 1;
break;
}
}
}
if (rev) {
tha.src = ip6->ip6_dst;
tha.dst = ip6->ip6_src;
tha.port = dport << 16 | sport;
} else {
tha.dst = ip6->ip6_dst;
tha.src = ip6->ip6_src;
tha.port = sport << 16 | dport;
}
} else {
if (sport > dport ||
(sport == dport &&
ip->ip_src.s_addr > ip->ip_dst.s_addr)) {
rev = 1;
}
if (rev) {
*(struct in_addr *)&tha.src = ip->ip_dst;
*(struct in_addr *)&tha.dst = ip->ip_src;
tha.port = dport << 16 | sport;
} else {
*(struct in_addr *)&tha.dst = ip->ip_dst;
*(struct in_addr *)&tha.src = ip->ip_src;
tha.port = sport << 16 | dport;
}
}
#else
if (sport < dport ||
(sport == dport &&
ip->ip_src.s_addr < ip->ip_dst.s_addr)) {
tha.src = ip->ip_src, tha.dst = ip->ip_dst;
tha.port = sport << 16 | dport;
rev = 0;
} else {
tha.src = ip->ip_dst, tha.dst = ip->ip_src;
tha.port = dport << 16 | sport;
rev = 1;
}
#endif
for (th = &tcp_seq_hash[tha.port % TSEQ_HASHSIZE];
th->nxt; th = th->nxt)
if (!memcmp((char *)&tha, (char *)&th->addr,
sizeof(th->addr)))
break;
if (!th->nxt || flags & TH_SYN) {
/* didn't find it or new conversation */
if (th->nxt == NULL) {
th->nxt = calloc(1, sizeof(*th));
if (th->nxt == NULL)
error("tcp_print: calloc");
}
th->addr = tha;
if (rev)
th->ack = seq, th->seq = ack - 1;
else
th->seq = seq, th->ack = ack - 1;
} else {
if (rev)
seq -= th->ack, ack -= th->seq;
else
seq -= th->seq, ack -= th->ack;
}
}
hlen = tp->th_off * 4;
if (hlen > length) {
(void)printf(" [bad hdr length]");
return;
}
if (ip && ip->ip_v == 4 && vflag) {
if (TTEST2(tp->th_sport, length)) {
u_int16_t sum, tcp_sum;
sum = tcp_cksum(ip, tp, length);
if (sum != 0) {
tcp_sum = EXTRACT_16BITS(&tp->th_sum);
(void)printf(" [bad tcp cksum %x! -> %x]", tcp_sum,
in_cksum_shouldbe(tcp_sum, sum));
} else
(void)printf(" [tcp sum ok]");
}
}
#ifdef INET6
if (ip6 && ip6->ip6_plen && vflag) {
if (TTEST2(tp->th_sport, length)) {
u_int16_t sum, tcp_sum;
sum = tcp6_cksum(ip6, tp, length);
if (sum != 0) {
tcp_sum = EXTRACT_16BITS(&tp->th_sum);
(void)printf(" [bad tcp cksum %x! -> %x]", tcp_sum,
in_cksum_shouldbe(tcp_sum, sum));
} else
(void)printf(" [tcp sum ok]");
}
}
#endif
/* OS Fingerprint */
if (oflag && (flags & (TH_SYN|TH_ACK)) == TH_SYN) {
struct pf_osfp_enlist *head = NULL;
struct pf_osfp_entry *fp;
unsigned long left;
left = (unsigned long)(snapend - (const u_char *)tp);
if (left >= hlen)
head = pf_osfp_fingerprint_hdr(ip, ip6, tp);
if (head) {
int prev = 0;
printf(" (src OS:");
SLIST_FOREACH(fp, head, fp_entry) {
if (fp->fp_enflags & PF_OSFP_EXPANDED)
continue;
if (prev)
printf(",");
printf(" %s", fp->fp_class_nm);
if (fp->fp_version_nm[0])
printf(" %s", fp->fp_version_nm);
if (fp->fp_subtype_nm[0])
printf(" %s", fp->fp_subtype_nm);
prev = 1;
}
printf(")");
} else {
if (left < hlen)
printf(" (src OS: short-pkt)");
else
printf(" (src OS: unknown)");
}
}
int
ip_output(struct mbuf * data, struct ip_socopts * so_optsPack) /* mbuf chain with data to send */
{
struct ip * bip;
struct tcphdr * tcpp;
PACKET pkt;
struct mbuf * m1, * m2, * mtmp; /* temp mbuf pointers */
int e; /* error holder */
int total;
/* reassemble mbufs into a contiguous packet. Do this with as
* little copying as possible. Typically the mbufs will be either
* 1) a single mbuf with iptcp header info only (e.g.tcp ACK
* packet), or 2) iptcp header with data mbuf chained to it, or 3)
* #2) with a tiny option data mbuf between header and data.
*/
if ((data->m_next))
{
m1 = data;
m2 = data->m_next;
/* If m2 is small (e.g. options), copy it to m1 and free it */
while (m2 && (m2->m_len < 10))
{
pkt = m1->pkt;
if ((pkt->nb_buff + pkt->nb_blen) > /* make sure m2 will fit in m1 */
(m1->m_data + m1->m_len + m2->m_len))
{
MEMCPY((m1->m_data + m1->m_len), m2->m_data, m2->m_len);
m1->m_len += m2->m_len;
m1->m_next = m2->m_next;
m_free(m2); /* free this m2.... */
m2 = m1->m_next; /* ...and thread the next one */
tcpstat.tcps_oappends++;
}
else /* if won't fit, fall to next copy */
break;
}
while (m2) /* If we still have two or more buffers, more copying: */
{
/* try prepending m1 to m2, first see if it fits: */
e = m2->m_data - m2->pkt->nb_buff; /* e is prepend space */
if (e < MaxLnh)
{
#ifdef NPDEBUG
dprintf("nptcp: MaxLnh:%d, e:%d\n", MaxLnh, e);
#endif
panic("tcp_out:mbuf-nbuf"); /* sanity check */
}
if ((m1->m_len < (unsigned)(e - MaxLnh)) /* leave room for MAC */
&& ((m1->m_len & (ALIGN_TYPE - 1)) == 0) /* and stay aligned */
&& ((m2->m_data - m2->pkt->nb_buff) == HDRSLEN)) /* be at start */
{
MEMCPY((m2->m_data - m1->m_len), m1->m_data, m1->m_len);
m2->m_data -= m1->m_len; /* fix target to reflect prepend */
m2->m_len += m1->m_len;
m_free(m1); /* free head (copied) mbuf */
data = m1 = m2; /* move other mbufs up the chain */
m2 = m2->m_next; /* loop to while(m2) test */
tcpstat.tcps_oprepends++;
}
else /* if won't fit, fall to next copy */
break;
}
if (m2) /* If all else fails, brute force copy: */
{
total = 0;
for (mtmp = m1; mtmp; mtmp = mtmp->m_next)
total += mtmp->m_len;
LOCK_NET_RESOURCE(FREEQ_RESID);
pkt = pk_alloc(total + HDRSLEN);
UNLOCK_NET_RESOURCE(FREEQ_RESID);
if (!pkt)
return ENOBUFS;
pkt->nb_prot = pkt->nb_buff + MaxLnh;
mtmp = m1;
while (mtmp)
{
MEMCPY(pkt->nb_prot, mtmp->m_data, mtmp->m_len);
pkt->nb_prot += mtmp->m_len;
pkt->nb_plen += mtmp->m_len;
m2 = mtmp;
mtmp = mtmp->m_next;
if (m2 != data) /* save original head */
m_free(m2);
tcpstat.tcps_ocopies++;
}
pkt->nb_prot -= total; /* fix data pointer */
/* release the original mbufs packet install the new one */
LOCK_NET_RESOURCE(FREEQ_RESID);
pk_free(data->pkt);
UNLOCK_NET_RESOURCE(FREEQ_RESID);
data->pkt = pkt;
data->m_len = pkt->nb_plen;
data->m_next = NULL;
data->m_data = pkt->nb_prot;
data->m_len = total;
}
}
if ((data->m_data < (data->pkt->nb_buff + MaxLnh)))
panic("ip_output: overflow");
pkt = data->pkt;
/* do we have options? */
if (so_optsPack)
pkt->soxopts = so_optsPack; /* yup */
#ifdef IP6_ROUTING
else
{
panic("ip_output: no so_optsPack for the IPv6 scope");
}
#endif
/* fill in dest host for IP layer */
bip = (struct ip *)data->m_data;
pkt->fhost = bip->ip_dest;
/* make enough IP header for cksum calculation */
bip->ip_ver_ihl = 0x45;
bip->ip_len = htons(bip->ip_len); /* make net endian for calculation */
tcpp = (struct tcphdr *)ip_data(bip);
#ifdef CSUM_DEMO
if (!(tcpp->th_flags & TH_SYN))
tcpp->th_flags |= TH_PUSH; /* force the PSH flag in TCP hdr */
#endif
tcpp->th_sum = tcp_cksum(bip);
pkt->nb_prot = (char*)(bip + 1); /* point past IP header */
pkt->nb_plen = data->m_len - sizeof(struct ip);
e = ip_write(IPPROTO_TCP, pkt);
/* ip_write() is now responsable for data->pkt, so... */
data->pkt = NULL;
m_freem(data);
if (e < 0)
{
/* don't report dropped sends, it causes socket applications to
bail when a TCP retry will fix the problem */
if (e == SEND_DROPPED)
return 0;
return e;
}
else
return 0;
}
void
tcp_print(register const u_char *bp, register u_int length,
register const u_char *bp2, int fragmented)
{
register const struct tcphdr *tp;
register const struct ip *ip;
register u_char flags;
register u_int hlen;
register char ch;
u_int16_t sport, dport, win, urp;
u_int32_t seq, ack, thseq, thack;
u_int utoval;
int threv;
#ifdef INET6
register const struct ip6_hdr *ip6;
#endif
tp = (struct tcphdr *)bp;
ip = (struct ip *)bp2;
#ifdef INET6
if (IP_V(ip) == 6)
ip6 = (struct ip6_hdr *)bp2;
else
ip6 = NULL;
#endif /*INET6*/
ch = '\0';
if (!TTEST(tp->th_dport)) {
(void)printf("%s > %s: [|tcp]",
ipaddr_string(&ip->ip_src),
ipaddr_string(&ip->ip_dst));
return;
}
sport = EXTRACT_16BITS(&tp->th_sport);
dport = EXTRACT_16BITS(&tp->th_dport);
hlen = TH_OFF(tp) * 4;
/*
* If data present, header length valid, and NFS port used,
* assume NFS.
* Pass offset of data plus 4 bytes for RPC TCP msg length
* to NFS print routines.
*/
if (!qflag && hlen >= sizeof(*tp) && hlen <= length &&
(length - hlen) >= 4) {
u_char *fraglenp;
u_int32_t fraglen;
register struct sunrpc_msg *rp;
enum sunrpc_msg_type direction;
fraglenp = (u_char *)tp + hlen;
if (TTEST2(*fraglenp, 4)) {
fraglen = EXTRACT_32BITS(fraglenp) & 0x7FFFFFFF;
if (fraglen > (length - hlen) - 4)
fraglen = (length - hlen) - 4;
rp = (struct sunrpc_msg *)(fraglenp + 4);
if (TTEST(rp->rm_direction)) {
direction = (enum sunrpc_msg_type)EXTRACT_32BITS(&rp->rm_direction);
if (dport == NFS_PORT &&
direction == SUNRPC_CALL) {
nfsreq_print((u_char *)rp, fraglen,
(u_char *)ip);
return;
}
if (sport == NFS_PORT &&
direction == SUNRPC_REPLY) {
nfsreply_print((u_char *)rp, fraglen,
(u_char *)ip);
return;
}
}
}
}
#ifdef INET6
if (ip6) {
if (ip6->ip6_nxt == IPPROTO_TCP) {
(void)printf("%s.%s > %s.%s: ",
ip6addr_string(&ip6->ip6_src),
tcpport_string(sport),
ip6addr_string(&ip6->ip6_dst),
tcpport_string(dport));
} else {
(void)printf("%s > %s: ",
tcpport_string(sport), tcpport_string(dport));
}
} else
#endif /*INET6*/
{
if (ip->ip_p == IPPROTO_TCP) {
(void)printf("%s.%s > %s.%s: ",
ipaddr_string(&ip->ip_src),
tcpport_string(sport),
ipaddr_string(&ip->ip_dst),
tcpport_string(dport));
} else {
(void)printf("%s > %s: ",
tcpport_string(sport), tcpport_string(dport));
}
}
if (hlen < sizeof(*tp)) {
(void)printf(" tcp %d [bad hdr length %u - too short, < %lu]",
length - hlen, hlen, (unsigned long)sizeof(*tp));
return;
}
TCHECK(*tp);
seq = EXTRACT_32BITS(&tp->th_seq);
ack = EXTRACT_32BITS(&tp->th_ack);
win = EXTRACT_16BITS(&tp->th_win);
urp = EXTRACT_16BITS(&tp->th_urp);
if (qflag) {
(void)printf("tcp %d", length - hlen);
if (hlen > length) {
(void)printf(" [bad hdr length %u - too long, > %u]",
hlen, length);
}
return;
}
flags = tp->th_flags;
printf("Flags [%s]", bittok2str_nosep(tcp_flag_values, "none", flags));
if (!Sflag && (flags & TH_ACK)) {
register struct tcp_seq_hash *th;
const void *src, *dst;
register int rev;
struct tha tha;
/*
* Find (or record) the initial sequence numbers for
* this conversation. (we pick an arbitrary
* collating order so there's only one entry for
* both directions).
*/
#ifdef INET6
rev = 0;
if (ip6) {
src = &ip6->ip6_src;
dst = &ip6->ip6_dst;
if (sport > dport)
rev = 1;
else if (sport == dport) {
if (memcmp(src, dst, sizeof ip6->ip6_dst) > 0)
rev = 1;
}
if (rev) {
memcpy(&tha.src, dst, sizeof ip6->ip6_dst);
memcpy(&tha.dst, src, sizeof ip6->ip6_src);
tha.port = dport << 16 | sport;
} else {
memcpy(&tha.dst, dst, sizeof ip6->ip6_dst);
memcpy(&tha.src, src, sizeof ip6->ip6_src);
tha.port = sport << 16 | dport;
}
} else {
/*
* Zero out the tha structure; the src and dst
* fields are big enough to hold an IPv6
* address, but we only have IPv4 addresses
* and thus must clear out the remaining 124
* bits.
*
* XXX - should we just clear those bytes after
* copying the IPv4 addresses, rather than
* zeroing out the entire structure and then
* overwriting some of the zeroes?
*
* XXX - this could fail if we see TCP packets
* with an IPv6 address with the lower 124 bits
* all zero and also see TCP packes with an
* IPv4 address with the same 32 bits as the
* upper 32 bits of the IPv6 address in question.
* Can that happen? Is it likely enough to be
* an issue?
*/
memset(&tha, 0, sizeof(tha));
src = &ip->ip_src;
dst = &ip->ip_dst;
if (sport > dport)
rev = 1;
else if (sport == dport) {
if (memcmp(src, dst, sizeof ip->ip_dst) > 0)
rev = 1;
}
if (rev) {
memcpy(&tha.src, dst, sizeof ip->ip_dst);
memcpy(&tha.dst, src, sizeof ip->ip_src);
tha.port = dport << 16 | sport;
} else {
memcpy(&tha.dst, dst, sizeof ip->ip_dst);
memcpy(&tha.src, src, sizeof ip->ip_src);
tha.port = sport << 16 | dport;
}
}
#else
rev = 0;
src = &ip->ip_src;
dst = &ip->ip_dst;
if (sport > dport)
rev = 1;
else if (sport == dport) {
if (memcmp(src, dst, sizeof ip->ip_dst) > 0)
rev = 1;
}
if (rev) {
memcpy(&tha.src, dst, sizeof ip->ip_dst);
memcpy(&tha.dst, src, sizeof ip->ip_src);
tha.port = dport << 16 | sport;
} else {
memcpy(&tha.dst, dst, sizeof ip->ip_dst);
memcpy(&tha.src, src, sizeof ip->ip_src);
tha.port = sport << 16 | dport;
}
#endif
threv = rev;
for (th = &tcp_seq_hash[tha.port % TSEQ_HASHSIZE];
th->nxt; th = th->nxt)
if (memcmp((char *)&tha, (char *)&th->addr,
sizeof(th->addr)) == 0)
break;
if (!th->nxt || (flags & TH_SYN)) {
/* didn't find it or new conversation */
if (th->nxt == NULL) {
th->nxt = (struct tcp_seq_hash *)
calloc(1, sizeof(*th));
if (th->nxt == NULL)
error("tcp_print: calloc");
}
th->addr = tha;
if (rev)
th->ack = seq, th->seq = ack - 1;
else
th->seq = seq, th->ack = ack - 1;
} else {
if (rev)
seq -= th->ack, ack -= th->seq;
else
seq -= th->seq, ack -= th->ack;
}
thseq = th->seq;
thack = th->ack;
} else {
/*fool gcc*/
thseq = thack = threv = 0;
}
if (hlen > length) {
(void)printf(" [bad hdr length %u - too long, > %u]",
hlen, length);
return;
}
if (vflag && !Kflag && !fragmented) {
/* Check the checksum, if possible. */
u_int16_t sum, tcp_sum;
if (IP_V(ip) == 4) {
if (TTEST2(tp->th_sport, length)) {
sum = tcp_cksum(ip, tp, length);
tcp_sum = EXTRACT_16BITS(&tp->th_sum);
(void)printf(", cksum 0x%04x", tcp_sum);
if (sum != 0)
(void)printf(" (incorrect -> 0x%04x)",
in_cksum_shouldbe(tcp_sum, sum));
else
(void)printf(" (correct)");
}
}
#ifdef INET6
else if (IP_V(ip) == 6 && ip6->ip6_plen) {
if (TTEST2(tp->th_sport, length)) {
sum = nextproto6_cksum(ip6, (const u_int8_t *)tp, length, IPPROTO_TCP);
tcp_sum = EXTRACT_16BITS(&tp->th_sum);
(void)printf(", cksum 0x%04x", tcp_sum);
if (sum != 0)
(void)printf(" (incorrect -> 0x%04x)",
in_cksum_shouldbe(tcp_sum, sum));
else
(void)printf(" (correct)");
}
}
#endif
}
length -= hlen;
if (vflag > 1 || length > 0 || flags & (TH_SYN | TH_FIN | TH_RST)) {
(void)printf(", seq %u", seq);
if (length > 0) {
(void)printf(":%u", seq + length);
}
}
if (flags & TH_ACK) {
(void)printf(", ack %u", ack);
}
(void)printf(", win %d", win);
if (flags & TH_URG)
(void)printf(", urg %d", urp);
/*
* Handle any options.
*/
if (hlen > sizeof(*tp)) {
register const u_char *cp;
register u_int i, opt, datalen;
register u_int len;
hlen -= sizeof(*tp);
cp = (const u_char *)tp + sizeof(*tp);
printf(", options [");
while (hlen > 0) {
if (ch != '\0')
putchar(ch);
TCHECK(*cp);
opt = *cp++;
if (ZEROLENOPT(opt))
len = 1;
else {
TCHECK(*cp);
len = *cp++; /* total including type, len */
if (len < 2 || len > hlen)
goto bad;
--hlen; /* account for length byte */
}
--hlen; /* account for type byte */
datalen = 0;
/* Bail if "l" bytes of data are not left or were not captured */
#define LENCHECK(l) { if ((l) > hlen) goto bad; TCHECK2(*cp, l); }
printf("%s", tok2str(tcp_option_values, "Unknown Option %u", opt));
switch (opt) {
case TCPOPT_MAXSEG:
datalen = 2;
LENCHECK(datalen);
(void)printf(" %u", EXTRACT_16BITS(cp));
break;
case TCPOPT_WSCALE:
datalen = 1;
LENCHECK(datalen);
(void)printf(" %u", *cp);
break;
case TCPOPT_SACK:
datalen = len - 2;
if (datalen % 8 != 0) {
(void)printf("malformed sack");
} else {
u_int32_t s, e;
(void)printf(" %d ", datalen / 8);
for (i = 0; i < datalen; i += 8) {
LENCHECK(i + 4);
s = EXTRACT_32BITS(cp + i);
LENCHECK(i + 8);
e = EXTRACT_32BITS(cp + i + 4);
if (threv) {
s -= thseq;
e -= thseq;
} else {
s -= thack;
e -= thack;
}
(void)printf("{%u:%u}", s, e);
}
}
break;
case TCPOPT_CC:
case TCPOPT_CCNEW:
case TCPOPT_CCECHO:
case TCPOPT_ECHO:
case TCPOPT_ECHOREPLY:
/*
* those options share their semantics.
* fall through
*/
datalen = 4;
LENCHECK(datalen);
(void)printf(" %u", EXTRACT_32BITS(cp));
break;
case TCPOPT_TIMESTAMP:
datalen = 8;
LENCHECK(datalen);
(void)printf(" val %u ecr %u",
EXTRACT_32BITS(cp),
EXTRACT_32BITS(cp + 4));
break;
case TCPOPT_SIGNATURE:
datalen = TCP_SIGLEN;
LENCHECK(datalen);
#ifdef HAVE_LIBCRYPTO
switch (tcp_verify_signature(ip, tp,
bp + TH_OFF(tp) * 4, length, cp)) {
case SIGNATURE_VALID:
(void)printf("valid");
break;
case SIGNATURE_INVALID:
(void)printf("invalid");
break;
case CANT_CHECK_SIGNATURE:
(void)printf("can't check - ");
for (i = 0; i < TCP_SIGLEN; ++i)
(void)printf("%02x", cp[i]);
break;
}
#else
for (i = 0; i < TCP_SIGLEN; ++i)
(void)printf("%02x", cp[i]);
#endif
break;
case TCPOPT_AUTH:
(void)printf("keyid %d", *cp++);
datalen = len - 3;
for (i = 0; i < datalen; ++i) {
LENCHECK(i);
(void)printf("%02x", cp[i]);
}
break;
case TCPOPT_EOL:
case TCPOPT_NOP:
case TCPOPT_SACKOK:
/*
* Nothing interesting.
* fall through
*/
break;
case TCPOPT_UTO:
datalen = 2;
LENCHECK(datalen);
utoval = EXTRACT_16BITS(cp);
(void)printf("0x%x", utoval);
if (utoval & 0x0001)
utoval = (utoval >> 1) * 60;
else
utoval >>= 1;
(void)printf(" %u", utoval);
break;
case TCPOPT_MPTCP: {
uint8_t subtype;
datalen = 1;
LENCHECK(datalen);
subtype = (*cp) >> 4;
printf(" %s ", tok2str(mptcp_subtypes, "Unknown MPTCP subtype %u", subtype));
switch (subtype) {
case TCPOPT_MPTCP_MP_CAPABLE: {
uint8_t version = (*cp) & 0x0f;
uint8_t mpflags;
if (version != 0) {
printf(" version %u ", version);
for (i = 0; i < datalen; ++i) {
LENCHECK(i);
(void)printf("%02x", cp[i]);
}
break;
}
datalen += 1;
LENCHECK(datalen);
mpflags = cp[1];
printf("%s%s%s%s%s%s%s%s%s",
(mpflags) ? "flags:" : "",
(mpflags & 0x80) ? "A" : "",
(mpflags & 0x40) ? "B" : "",
(mpflags & 0x20) ? "C" : "",
(mpflags & 0x10) ? "D" : "",
(mpflags & 0x08) ? "E" : "",
(mpflags & 0x04) ? "F" : "",
(mpflags & 0x02) ? "G" : "",
(mpflags & 0x01) ? "H" : "");
if (len == 12 || len == 20) {
printf(" sndkey:");
for (i = 0; i < 8; ++i) {
datalen++;
LENCHECK(datalen);
(void)printf("%02x", cp[2 + i]);
}
if (len == 20) {
printf(" rcvkey:");
for (i = 0; i < 8; ++i) {
datalen++;
LENCHECK(datalen);
(void)printf("%02x", cp[10 + i]);
}
}
} else {
printf(" unknown:");
datalen = len - 2;
for (i = 0; i < datalen; ++i) {
LENCHECK(i);
(void)printf("%02x", cp[i]);
}
}
break;
}
case TCPOPT_MPTCP_MP_JOIN: {
uint8_t mpflags = (*cp) & 0x0f;
/* Flags on SYN only */
if (flags & TH_SYN) {
printf("%s%s%s%s%s",
(mpflags) ? "flags:" : "",
(mpflags & 0x08) ? "0" : "",
(mpflags & 0x04) ? "1" : "",
(mpflags & 0x02) ? "2" : "",
(mpflags & 0x01) ? "B" : "");
}
/* Address ID on SYN only, otherwise ignored */
datalen += 1;
LENCHECK(datalen);
if ((flags & TH_SYN))
printf(" addrid:%0x", cp[1]);
if (flags == TH_SYN && len == 12) {
/* Initial SYN */
printf(" rcvtok:");
for (i = 0; i < 4; ++i) {
datalen++;
LENCHECK(datalen);
(void)printf("%02x", cp[2 + i]);
}
printf(" sndrand:");
for (i = 0; i < 4; ++i) {
datalen++;
LENCHECK(datalen);
(void)printf("%02x", cp[6 + i]);
}
} else if ((flags & (TH_SYN | TH_ACK)) == (TH_SYN | TH_ACK) && len == 16) {
/* Responding SYN/ACK */
printf(" sndhmac:");
for (i = 0; i < 8; ++i) {
datalen++;
LENCHECK(datalen);
(void)printf("%02x", cp[2 + i]);
}
printf(" sndrand:");
for (i = 0; i < 4; ++i) {
datalen++;
LENCHECK(datalen);
(void)printf("%02x", cp[8 + i]);
}
} else if ((flags & (TH_SYN | TH_ACK)) == TH_ACK && len == 24) {
/* Third ACK */
printf(" sndhmac:");
for (i = 0; i < 20; ++i) {
datalen++;
LENCHECK(i);
(void)printf("%02x", cp[2 + i]);
}
} else {
datalen = len - 2;
for (i = 0; i < datalen; ++i) {
LENCHECK(i);
(void)printf("%02x", cp[i]);
}
}
break;
}
case TCPOPT_MPTCP_DSS: {
uint8_t mpflags;
u_int ack_len = 0;
u_int dsn_len = 0;
u_int64_t dack;
u_int64_t dsn;
u_int32_t sfsn;
u_int16_t dlen;
u_int16_t csum;
datalen += 1;
LENCHECK(datalen);
mpflags = cp[1] & 0x1f;
printf("%s%s%s%s%s%s",
(mpflags) ? "flags:" : "",
(mpflags & 0x10) ? "F" : "",
(mpflags & 0x08) ? "m" : "",
(mpflags & 0x04) ? "M" : "",
(mpflags & 0x02) ? "a" : "",
(mpflags & 0x01) ? "A" : "");
if ((mpflags & MPDSS_FLAG_A)) {
if ((mpflags & MPDSS_FLAG_a)) {
ack_len = 8;
datalen += ack_len;
LENCHECK(datalen);
dack = EXTRACT_64BITS(cp + 2);
} else {
ack_len = 4;
datalen += ack_len;
LENCHECK(datalen);
dack = EXTRACT_32BITS(cp + 2);
}
(void)printf(" dack: %" PRIu64, dack);
}
if ((mpflags & MPDSS_FLAG_M)) {
if ((mpflags & MPDSS_FLAG_m)) {
dsn_len = 8;
datalen += dsn_len;
LENCHECK(datalen);
dsn = EXTRACT_64BITS(cp + 2 + ack_len);
} else {
dsn_len = 4;
datalen += dsn_len;
LENCHECK(datalen);
dsn = EXTRACT_32BITS(cp + 2 + ack_len);
}
(void)printf(" dsn: %" PRIu64, dsn);
datalen += 4;
LENCHECK(datalen);
sfsn = EXTRACT_32BITS(cp + 2 + ack_len + dsn_len);
(void)printf(" sfsn: %" PRIu32, sfsn);
datalen += 2;
LENCHECK(datalen);
dlen = EXTRACT_16BITS(cp + 2 + ack_len + dsn_len + 4);
(void)printf(" dlen: %" PRIu16, dlen);
/*
* Use the length of the option to find out if
* the checksum is present
*/
if (datalen < len - 2) {
datalen += 2;
LENCHECK(datalen);
csum = EXTRACT_16BITS(cp + 2 + ack_len + dsn_len + 6);
(void)printf(" csum: %" PRIu16, csum);
}
}
break;
}
case TCPOPT_MPTCP_ADD_ADDR: {
uint8_t ipvers;
u_int addrlen = 0;
u_int16_t port;
ipvers = cp[1] & 0xf0;
printf(" vers:%u", ipvers);
datalen = 2;
LENCHECK(datalen);
printf(" addrid:%0x", cp[1]);
switch (ipvers) {
case 4: {
datalen = 6;
LENCHECK(datalen);
ipaddr_string(cp + 2);
break;
}
case 6: {
datalen = 18;
LENCHECK(datalen);
#ifdef INET6
ip6addr_string(cp + 2);
#endif
break;
}
default:
goto bad;
}
/*
* Use the length of the option to find out if
* the port is present
*/
if (datalen < len - 2) {
datalen += 2;
LENCHECK(datalen);
port = EXTRACT_16BITS(cp + 2 + addrlen);
printf(" port: %u", port);
}
break;
}
case TCPOPT_MPTCP_REMOVE_ADDR:
datalen = len - 2;
for (i = 0; i < datalen; ++i) {
LENCHECK(i);
(void)printf(" %u", cp[i]);
}
break;
case TCPOPT_MPTCP_MP_PRIO: {
uint8_t mpflags = (*cp) & 0x0f;
if (mpflags == 0x01)
printf("flag B");
else if (mpflags != 0) {
printf("flag %c%c%c%c%c%c%c%c",
mpflags & 0x80 ? '1' : '0',
mpflags & 0x40 ? '1' : '0',
mpflags & 0x20 ? '1' : '0',
mpflags & 0x10 ? '1' : '0',
mpflags & 0x08 ? '1' : '0',
mpflags & 0x04 ? '1' : '0',
mpflags & 0x02 ? '1' : '0',
mpflags & 0x01 ? 'B' : '0');
}
if (len == 4) {
datalen = 2;
LENCHECK(datalen);
printf("%saddrid:%u", mpflags ? " " : "", cp[1]);
}
break;
}
case TCPOPT_MPTCP_MP_FAIL:
datalen = 10;
LENCHECK(datalen);
printf(" dsn:");
for (i = 0; i < 8; ++i) {
(void)printf("%02x", cp[2 + i]);
}
break;
case TCPOPT_MPTCP_MP_FASTCLOSE:
datalen = 10;
LENCHECK(datalen);
printf(" rcvrkey:");
for (i = 0; i < 8; ++i) {
(void)printf("%02x", cp[2 + i]);
}
break;
default:
datalen = len - 2;
for (i = 0; i < datalen; ++i) {
LENCHECK(i);
(void)printf("%02x", cp[i]);
}
break;
}
break;
}
default:
datalen = len - 2;
for (i = 0; i < datalen; ++i) {
LENCHECK(i);
(void)printf("%02x", cp[i]);
}
break;
}
/* Account for data printed */
cp += datalen;
hlen -= datalen;
/* Check specification against observed length */
++datalen; /* option octet */
if (!ZEROLENOPT(opt))
++datalen; /* size octet */
if (datalen != len)
(void)printf("[len %d]", len);
ch = ',';
if (opt == TCPOPT_EOL)
break;
}
putchar(']');
}