Путь: Toys/Pending, команды версии: Ver.4 Ver.9 traceroute Комментарии в файле traceroute.c :
Исходный текст в файле traceroute.c #define FOR_traceroute
#include "toys.h"
#include <netinet/udp.h>
#include <netinet/ip_icmp.h>
#include <netinet/ip6.h>
#include <netinet/icmp6.h>
GLOBALS(
long max_ttl;
long port;
long ttl_probes;
char *src_ip;
long tos;
long wait_time;
struct arg_list *loose_source;
long pause_time;
long first_ttl;
char *iface;
uint32_t gw_list[9];
int recv_sock;
int snd_sock;
unsigned msg_len;
char *packet;
uint32_t ident;
int istraceroute6;
)
#ifndef SOL_IPV6
# define SOL_IPV6 IPPROTO_IPV6
#endif
#define ICMP_HD_SIZE4 8
#define USEC 1000000ULL
struct payload_s {
uint32_t seq;
uint32_t ident;
};
char addr_str[INET6_ADDRSTRLEN];
struct sockaddr_storage dest;
//Compute checksum SUM of buffer P of length LEN
static u_int16_t in_cksum(u_int16_t *p, u_int len)
{
u_int32_t sum = 0;
int nwords = len >> 1;
while (nwords-- != 0) sum += *p++;
if (len & 1) {
union {
u_int16_t w;
u_int8_t c[2];
} u;
u.c[0] = *(u_char *) p;
u.c[1] = 0;
sum += u.w;
}
// end-around-carry
sum = (sum >> 16) + (sum & 0xffff);
sum += (sum >> 16);
return (~sum);
}
//sends a single probe packet with sequence(SEQ) and time-to-live(TTL)
static void send_probe4(int seq, int ttl)
{
int res, len;
void *out;
struct payload_s *send_data4 = (struct payload_s *)(TT.packet);
struct icmp *send_icmp4 = (struct icmp *)(TT.packet);
if (toys.optflags & FLAG_U) {
send_data4->seq = seq;
send_data4->ident = TT.ident;
((struct sockaddr_in *)&dest)->sin_port = TT.port + seq;
out = send_data4;
} else {
send_icmp4->icmp_type = ICMP_ECHO;
send_icmp4->icmp_id = htons(TT.ident);
send_icmp4->icmp_seq = htons(seq);
send_icmp4->icmp_cksum = 0;
send_icmp4->icmp_cksum = in_cksum((uint16_t *) send_icmp4, TT.msg_len);
if (send_icmp4->icmp_cksum == 0) send_icmp4->icmp_cksum = 0xffff;
out = send_icmp4;
}
res = setsockopt(TT.snd_sock, IPPROTO_IP, IP_TTL, &ttl, sizeof(ttl));
if (res < 0) perror_exit("setsockopt ttl %d", ttl);
len = TT.msg_len;
res = sendto(TT.snd_sock, out, len, 0, (struct sockaddr *) &dest,
sizeof(struct sockaddr_in));
if (res != len) perror_exit(" sendto");
}
//sends a single probe packet with sequence(SEQ) and time-to-live(TTL)
static void send_probe6(int seq, int ttl)
{
void *out;
struct payload_s *send_data6 = (struct payload_s *) (TT.packet);
send_data6->seq = seq;
send_data6->ident = TT.ident;
((struct sockaddr_in6 *)&dest)->sin6_port = TT.port;
if (setsockopt(TT.snd_sock, SOL_IPV6, IPV6_UNICAST_HOPS, &ttl,
sizeof(ttl)) < 0) error_exit("setsockopt ttl %d", ttl);
out = send_data6;
if (sendto(TT.snd_sock, out, TT.msg_len, 0,
(struct sockaddr *) &dest, sizeof(struct sockaddr_in6)) < 0)
perror_exit("sendto");
}
static void set_flag_dr(int sock)
{
int set = 1;
if ((toys.optflags & FLAG_d) && (setsockopt(sock,SOL_SOCKET, SO_DEBUG,
&set, sizeof(set)) < 0)) perror_exit("SO_DEBUG failed ");
if ((toys.optflags & FLAG_r) && (setsockopt(sock, SOL_SOCKET, SO_DONTROUTE,
&set, sizeof(set)) < 0)) perror_exit("SO_DONTROUTE failed ");
}
static void bind_to_interface(int sock)
{
struct ifreq ifr;
snprintf(ifr.ifr_name, IFNAMSIZ, "%s", TT.iface);
if (setsockopt(sock, SOL_SOCKET, SO_BINDTODEVICE, &ifr, sizeof(ifr)))
perror_msg("can't bind to interface %s", TT.iface);
}
static void resolve_addr(char *host, int family, int type, int proto, void *sock)
{
struct addrinfo *info, hint;
int ret;
memset(&hint, 0, sizeof(hint));
hint.ai_family = family;
hint.ai_socktype = type;
hint.ai_protocol = proto;
ret = getaddrinfo(host, NULL, &hint, &info);
if (ret || !info) error_exit("bad address: %s ", host);
memcpy(sock, info->ai_addr, info->ai_addrlen);
freeaddrinfo(info);
}
static void do_trace()
{
int seq, fexit, ttl, tv = TT.wait_time * 1000;
struct pollfd pfd[1];
struct sockaddr_storage from;
memset(&from, 0, sizeof(from));
pfd[0].fd = TT.recv_sock;
pfd[0].events = POLLIN;
for (ttl = TT.first_ttl; ttl <= TT.max_ttl; ++ttl) {
int probe, dest_reach = 0, print_verbose = 1;
struct timeval t1, t2;
struct sockaddr_storage last_addr;
memset(&last_addr, 0, sizeof(last_addr));
fexit = 0;
xprintf("%2d", ttl);
for (probe = 0, seq = 0; probe < TT.ttl_probes; ++probe) {
int res = 0, tleft;
fflush(NULL);
if (!TT.istraceroute6)
if (probe && (toys.optflags & FLAG_z)) msleep(TT.pause_time);
if (!TT.istraceroute6) send_probe4(++seq, ttl);
else send_probe6(++seq, ttl);
gettimeofday(&t1, NULL);
t2 = t1;
while ((tleft = (int)(tv - ((unsigned long long)(t2.tv_sec * 1000ULL
+ t2.tv_usec/1000) - (unsigned long long)(t1.tv_sec * 1000ULL
+ t1.tv_usec/1000)))) >= 0) {
unsigned delta = 0;
if (!(res = poll(pfd, 1, tleft))) {
xprintf(" *");
break;
}
gettimeofday(&t2, NULL);
if (res < 0) {
if (errno != EINTR) perror_exit("poll");
continue;
}
delta = (t2.tv_sec * USEC + t2.tv_usec)
- (t1.tv_sec * USEC + t1.tv_usec);
if (pfd[0].revents) {
socklen_t addrlen = sizeof(struct sockaddr_storage);
int rcv_len, icmp_res = 0;
rcv_len = recvfrom(TT.recv_sock, toybuf, sizeof(toybuf),
MSG_DONTWAIT, (struct sockaddr *) &from, &addrlen);
if (rcv_len <= 0) continue;
if (!TT.istraceroute6) {
int pmtu = 0;
struct ip *rcv_pkt = (struct ip*) toybuf;
struct icmp *ricmp;
ricmp = (struct icmp *) ((char*)rcv_pkt + (rcv_pkt->ip_hl << 2));
if (ricmp->icmp_code == ICMP_UNREACH_NEEDFRAG)
pmtu = ntohs(ricmp->icmp_nextmtu);
if ((ricmp->icmp_type == ICMP_TIMXCEED
&& ricmp->icmp_code == ICMP_TIMXCEED_INTRANS)
|| ricmp->icmp_type == ICMP_UNREACH
|| ricmp->icmp_type == ICMP_ECHOREPLY) {
struct udphdr *hudp;
struct icmp *hicmp;
struct ip *hip = &ricmp->icmp_ip;
if (toys.optflags & FLAG_U) {
hudp = (struct udphdr*) ((char*)hip + (hip->ip_hl << 2));
if ((hip->ip_hl << 2) + 12 <=(rcv_len - (rcv_pkt->ip_hl << 2))
&& hip->ip_p == IPPROTO_UDP
&& hudp->dest == (TT.port + seq))
icmp_res = (ricmp->icmp_type == ICMP_TIMXCEED ? -1 :
ricmp->icmp_code);
} else {
hicmp = (struct icmp *) ((char*)hip + (hip->ip_hl << 2));
if (ricmp->icmp_type == ICMP_ECHOREPLY
&& ricmp->icmp_id == ntohs(TT.ident)
&& ricmp->icmp_seq == ntohs(seq))
icmp_res = ICMP_UNREACH_PORT;
else if ((hip->ip_hl << 2) + ICMP_HD_SIZE4
<= (rcv_len - (rcv_pkt->ip_hl << 2))
&& hip->ip_p == IPPROTO_ICMP
&& hicmp->icmp_id == htons(TT.ident)
&& hicmp->icmp_seq == htons(seq))
icmp_res = (ricmp->icmp_type == ICMP_TIMXCEED ? -1 :
ricmp->icmp_code);
}
}
if (!icmp_res) continue;
if (addrlen > 0) {
if (memcmp(&((struct sockaddr_in *)&last_addr)->sin_addr,
&((struct sockaddr_in *)&from)->sin_addr,
sizeof(struct in_addr))) {
if (!(toys.optflags & FLAG_n)) {
char host[NI_MAXHOST];
if (!getnameinfo((struct sockaddr *) &from,
sizeof(struct sockaddr_in), host, NI_MAXHOST, NULL, 0, 0))
xprintf(" %s (", host);
else xprintf(" %s (", inet_ntoa(
((struct sockaddr_in *)&from)->sin_addr));
}
xprintf(" %s", inet_ntoa(
((struct sockaddr_in *)&from)->sin_addr));
if (!(toys.optflags & FLAG_n)) xprintf(")");
memcpy(&last_addr, &from, sizeof(from));
}
xprintf(" %u.%03u ms", delta / 1000, delta % 1000);
if (toys.optflags & FLAG_l) xprintf(" (%d)", rcv_pkt->ip_ttl);
if (toys.optflags & FLAG_v) {
xprintf(" %d bytes from %s : icmp type %d code %d\t",
rcv_len, inet_ntoa(((struct sockaddr_in *)&from)->sin_addr),
ricmp->icmp_type, ricmp->icmp_code);
}
} else xprintf("\t!H");
switch (icmp_res) {
case ICMP_UNREACH_PORT:
if (rcv_pkt->ip_ttl <= 1) xprintf(" !");
dest_reach = 1;
break;
case ICMP_UNREACH_NET:
xprintf(" !N");
++fexit;
break;
case ICMP_UNREACH_HOST:
xprintf(" !H");
++fexit;
break;
case ICMP_UNREACH_PROTOCOL:
xprintf(" !P");
dest_reach = 1;
break;
case ICMP_UNREACH_NEEDFRAG:
xprintf(" !F-%d", pmtu);
++fexit;
break;
case ICMP_UNREACH_SRCFAIL:
xprintf(" !S");
++fexit;
break;
case ICMP_UNREACH_FILTER_PROHIB:
case ICMP_UNREACH_NET_PROHIB:
xprintf(" !A");
++fexit;
break;
case ICMP_UNREACH_HOST_PROHIB:
xprintf(" !C");
++fexit;
break;
case ICMP_UNREACH_HOST_PRECEDENCE:
xprintf(" !V");
++fexit;
break;
case ICMP_UNREACH_PRECEDENCE_CUTOFF:
xprintf(" !C");
++fexit;
break;
case ICMP_UNREACH_NET_UNKNOWN:
case ICMP_UNREACH_HOST_UNKNOWN:
xprintf(" !U");
++fexit;
break;
case ICMP_UNREACH_ISOLATED:
xprintf(" !I");
++fexit;
break;
case ICMP_UNREACH_TOSNET:
case ICMP_UNREACH_TOSHOST:
xprintf(" !T");
++fexit;
break;
default:
break;
}
break;
} else {
struct icmp6_hdr *ricmp = (struct icmp6_hdr *) toybuf;
if ((ricmp->icmp6_type == ICMP6_TIME_EXCEEDED
&& ricmp->icmp6_code == ICMP6_TIME_EXCEED_TRANSIT)
|| ricmp->icmp6_type == ICMP6_DST_UNREACH
|| ricmp->icmp6_type == ICMP6_ECHO_REPLY) {
struct ip6_hdr *hip;
struct udphdr *hudp;
int hdr_next;
hip = (struct ip6_hdr *)(ricmp + 1);
hudp = (struct udphdr*) (hip + 1);
hdr_next = hip->ip6_nxt;
if (hdr_next == IPPROTO_FRAGMENT) {
hdr_next = *(unsigned char*)hudp;
hudp++;
}
if (hdr_next == IPPROTO_UDP) {
struct payload_s *pkt = (struct payload_s*)(hudp + 1);
if ((pkt->ident == TT.ident) && (pkt->seq == seq))
icmp_res = (ricmp->icmp6_type == ICMP6_TIME_EXCEEDED) ? -1 :
ricmp->icmp6_code;
}
}
if (!icmp_res) continue;
if (addrlen > 0) {
if (memcmp(&((struct sockaddr_in6 *)&last_addr)->sin6_addr,
&((struct sockaddr_in6 *)&from)->sin6_addr,
sizeof(struct in6_addr))) {
if (!(toys.optflags & FLAG_n)) {
char host[NI_MAXHOST];
if (!getnameinfo((struct sockaddr *) &from,
sizeof(from), host, sizeof(host), NULL, 0, 0))
xprintf(" %s (", host);
}
memset(addr_str, '\0', INET6_ADDRSTRLEN);
inet_ntop(AF_INET6, &((struct sockaddr_in6 *)&from)->sin6_addr,
addr_str, INET6_ADDRSTRLEN);
xprintf(" %s", addr_str);
if (!(toys.optflags & FLAG_n)) xprintf(")");
memcpy(&last_addr,&from,sizeof(from));
}
if (toys.optflags & FLAG_v) {
if(print_verbose){
memset(addr_str, '\0', INET6_ADDRSTRLEN);
inet_ntop(AF_INET6, &((struct sockaddr_in6 *)
&from)->sin6_addr, addr_str, INET6_ADDRSTRLEN);
rcv_len -= sizeof(struct ip6_hdr);
xprintf(" %d bytes to %s ", rcv_len, addr_str);
}
}
xprintf(" %u.%03u ms", delta / 1000, delta % 1000);
delta = 0;
} else xprintf("\t!H");
switch (icmp_res) {
case ICMP6_DST_UNREACH_NOPORT:
++fexit;
dest_reach = 1;
break;
case ICMP6_DST_UNREACH_NOROUTE:
xprintf(" !N");
++fexit;
break;
case ICMP6_DST_UNREACH_ADDR:
xprintf(" !H");
++fexit;
break;
case ICMP6_DST_UNREACH_ADMIN:
xprintf(" !S");
++fexit;
break;
default:
break;
}
break;
}
} //revents
}
print_verbose = 0;
}
xputc('\n');
if(!TT.istraceroute6) {
if (!memcmp(&((struct sockaddr_in *)&from)->sin_addr,
&((struct sockaddr_in *)&dest)->sin_addr, sizeof(struct in_addr))
|| dest_reach || (fexit && fexit >= TT.ttl_probes -1))
break;
} else if (dest_reach || (fexit > 0 && fexit >= TT.ttl_probes -1)) break;
}
}
void traceroute_main(void)
{
unsigned pack_size = 0, tyser = 0;
int lsrr = 0, set = 1;
if(!(toys.optflags & FLAG_4) &&
(inet_pton(AF_INET6, toys.optargs[0], &dest)))
toys.optflags |= FLAG_6;
memset(&dest, 0, sizeof(dest));
if (toys.optflags & FLAG_6) TT.istraceroute6 = 1;
else TT.istraceroute6 = toys.which->name[10] == '6';
if(!TT.istraceroute6 && (toys.optflags & FLAG_g)) {
struct arg_list *node;
for (node = TT.loose_source; node; node = node->next, lsrr++) {
struct sockaddr_in sin;
memset( &sin, 0, sizeof(sin));
if (lsrr >= 8) error_exit("no more than 8 gateways"); // NGATEWAYS
resolve_addr(node->arg, AF_INET, SOCK_STREAM, 0, &sin);
TT.gw_list[lsrr] = sin.sin_addr.s_addr;
}
} else TT.first_ttl = 1;
TT.msg_len = pack_size = ICMP_HD_SIZE4; //udp payload is also 8bytes
if (toys.optargs[1])
TT.msg_len = atolx_range(toys.optargs[1], pack_size, 32768);//max packet size
TT.recv_sock = xsocket((TT.istraceroute6 ? AF_INET6 : AF_INET), SOCK_RAW,
(TT.istraceroute6 ? IPPROTO_ICMPV6 : IPPROTO_ICMP));
if (TT.istraceroute6) {
int two = 2;
#ifdef IPV6_RECVPKTINFO
setsockopt(TT.recv_sock, SOL_IPV6, IPV6_RECVPKTINFO, &set,
sizeof(set));
setsockopt(TT.recv_sock, SOL_IPV6, IPV6_2292PKTINFO, &set,
sizeof(set));
#else
setsockopt(TT.recv_sock, SOL_IPV6, IPV6_PKTINFO, &set, sizeof(set));
#endif
if (setsockopt(TT.recv_sock, SOL_RAW, IPV6_CHECKSUM, &two,
sizeof(two)) < 0) perror_exit("setsockopt RAW_CHECKSUM");
}
set_flag_dr(TT.recv_sock);
if (!TT.istraceroute6) {
if (toys.optflags & FLAG_U)
TT.snd_sock = xsocket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
else TT.snd_sock = xsocket(AF_INET, SOCK_RAW, IPPROTO_ICMP);
if (toys.optflags & FLAG_i) bind_to_interface(TT.snd_sock);
resolve_addr(toys.optargs[0], AF_INET, ((toys.optflags & FLAG_U) ?
SOCK_DGRAM : SOCK_RAW), ((toys.optflags & FLAG_U) ? IPPROTO_UDP :
IPPROTO_ICMP), &dest);
if (lsrr > 0) {
unsigned char optlist[MAX_IPOPTLEN];
unsigned size;
TT.gw_list[lsrr] = ((struct sockaddr_in *)&dest)->sin_addr.s_addr;
++lsrr;
optlist[0] = IPOPT_NOP;
optlist[1] = IPOPT_LSRR;// loose source route option
size = lsrr * sizeof(TT.gw_list[0]);
optlist[2] = size + 3;
optlist[3] = IPOPT_MINOFF;
memcpy(optlist + 4, TT.gw_list, size);
if (setsockopt(TT.snd_sock, IPPROTO_IP, IP_OPTIONS,
(char *)optlist, size + sizeof(TT.gw_list[0])) < 0)
perror_exit("LSRR IP_OPTIONS");
}
} else TT.snd_sock = xsocket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP);
if (setsockopt(TT.snd_sock, SOL_SOCKET, SO_SNDBUF, &TT.msg_len,
sizeof(TT.msg_len)) < 0) perror_exit("SO_SNDBUF failed ");
if (!TT.istraceroute6) {
if ((toys.optflags & FLAG_t) &&
setsockopt(TT.snd_sock, IPPROTO_IP, IP_TOS, &tyser, sizeof(tyser)) < 0)
perror_exit("IP_TOS %ld failed ", TT.tos);
#ifdef IP_DONTFRAG
if ((toys.optflags & FLAG_F) &&
(setsockopt(TT.snd_sock, IPPROTO_IP, IP_DONTFRAG, &set,
sizeof(set)) < 0)) perror_exit("IP_DONTFRAG failed ");
#endif
} else if (setsockopt(TT.snd_sock, IPPROTO_IPV6, IPV6_TCLASS, &TT.tos,
sizeof(TT.tos)) < 0) perror_exit("IPV6_TCLASS %ld failed ", TT.tos);
set_flag_dr(TT.snd_sock);
TT.packet = xzalloc(TT.msg_len);
TT.ident = getpid();
if (!TT.istraceroute6) {
if (!(toys.optflags & FLAG_U)) TT.ident |= 0x8000;
if (toys.optflags & FLAG_s) {
struct sockaddr_in source;
memset(&source, 0, sizeof(source));
if (!inet_aton(TT.src_ip, &(source.sin_addr)))
error_exit("bad address: %s", TT.src_ip);
if (setsockopt(TT.snd_sock, IPPROTO_IP, IP_MULTICAST_IF,
(struct sockaddr*)&source, sizeof(struct sockaddr_in)))
perror_exit("can't set multicast source interface");
xbind(TT.snd_sock,(struct sockaddr*)&source, sizeof(struct sockaddr_in));
}
if(TT.first_ttl > TT.max_ttl)
error_exit("ERROR :Range for -f is 1 to %ld (max ttl)", TT.max_ttl);
xprintf("traceroute to %s(%s)", toys.optargs[0],
inet_ntoa(((struct sockaddr_in *)&dest)->sin_addr));
} else {
if (toys.optflags & FLAG_i) bind_to_interface(TT.snd_sock);
resolve_addr(toys.optargs[0], AF_INET6, SOCK_DGRAM, IPPROTO_UDP, &dest);
if (toys.optflags & FLAG_s) {
struct sockaddr_in6 source;
memset(&source, 0, sizeof(source));
if(inet_pton(AF_INET6, TT.src_ip, &(source.sin6_addr)) <= 0)
error_exit("bad address: %s", TT.src_ip);
xbind(TT.snd_sock,(struct sockaddr*)&source, sizeof(struct sockaddr_in6));
} else {
struct sockaddr_in6 prb;
socklen_t len = sizeof(prb);
int p_fd = xsocket(AF_INET6, SOCK_DGRAM, 0);
if (toys.optflags & FLAG_i) bind_to_interface(p_fd);
((struct sockaddr_in6 *)&dest)->sin6_port = htons(1025);
xconnect(p_fd, (struct sockaddr *)&dest, sizeof(struct sockaddr_in6));
if(getsockname(p_fd, (struct sockaddr *)&prb, &len))
error_exit("probe addr failed");
close(p_fd);
prb.sin6_port = 0;
xbind(TT.snd_sock, (struct sockaddr*)&prb, sizeof(struct sockaddr_in6));
xbind(TT.recv_sock, (struct sockaddr*)&prb, sizeof(struct sockaddr_in6));
}
inet_ntop(AF_INET6, &((struct sockaddr_in6 *)&dest)->sin6_addr,
addr_str, INET6_ADDRSTRLEN);
xprintf("traceroute6 to %s(%s)", toys.optargs[0], addr_str);
}
if (toys.optflags & FLAG_s) xprintf(" from %s",TT.src_ip);
xprintf(", %ld hops max, %u byte packets\n", TT.max_ttl, TT.msg_len);
do_trace();
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