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/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/Assertions.h>
#include <AK/ByteBuffer.h>
#include <LibCore/ArgsParser.h>
#include <arpa/inet.h>
#include <errno.h>
#include <netdb.h>
#include <netinet/in.h>
#include <netinet/ip.h>
#include <netinet/ip_icmp.h>
#include <serenity.h>
#include <signal.h>
#include <stdio.h>
#include <string.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <time.h>
#include <unistd.h>
static int total_pings;
static int successful_pings;
static int count;
static uint32_t total_ms;
static int min_ms;
static int max_ms;
static const char* host;
static int payload_size = -1;
// variable part of header can be 0 to 40 bytes
// https://datatracker.ietf.org/doc/html/rfc791#section-3.1
static constexpr int max_optional_header_size_in_bytes = 40;
static constexpr int min_header_size_in_bytes = 5;
static void closing_statistics()
{
int packet_loss = 100;
outln();
outln("--- {} ping statistics ---", host);
if (total_pings)
packet_loss -= 100.0f * successful_pings / total_pings;
outln("{} packets transmitted, {} received, {}% packet loss",
total_pings, successful_pings, packet_loss);
int average_ms = 0;
if (successful_pings)
average_ms = total_ms / successful_pings;
outln("rtt min/avg/max = {}/{}/{} ms", min_ms, average_ms, max_ms);
exit(0);
};
int main(int argc, char** argv)
{
if (pledge("stdio id inet unix sigaction", nullptr) < 0) {
perror("pledge");
return 1;
}
Core::ArgsParser args_parser;
args_parser.add_positional_argument(host, "Host to ping", "host");
args_parser.add_option(count, "Stop after sending specified number of ECHO_REQUEST packets.", "count", 'c', "count");
args_parser.add_option(payload_size, "Amount of bytes to send as payload in the ECHO_REQUEST packets.", "size", 's', "size");
args_parser.parse(argc, argv);
if (payload_size < 0) {
// Use the default.
payload_size = 32 - sizeof(struct icmphdr);
}
int fd = socket(AF_INET, SOCK_RAW, IPPROTO_ICMP);
if (fd < 0) {
perror("socket");
return 1;
}
if (setgid(getgid()) || setuid(getuid())) {
warnln("Failed to drop privileges.");
return 1;
}
if (pledge("stdio inet unix sigaction", nullptr) < 0) {
perror("pledge");
return 1;
}
struct timeval timeout {
1, 0
};
int rc = setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, &timeout, sizeof(timeout));
if (rc < 0) {
perror("setsockopt");
return 1;
}
auto* hostent = gethostbyname(host);
if (!hostent) {
warnln("Lookup failed for '{}'", host);
return 1;
}
if (pledge("stdio inet sigaction", nullptr) < 0) {
perror("pledge");
return 1;
}
pid_t pid = getpid();
sockaddr_in peer_address;
memset(&peer_address, 0, sizeof(peer_address));
peer_address.sin_family = AF_INET;
peer_address.sin_port = 0;
peer_address.sin_addr.s_addr = *(const in_addr_t*)hostent->h_addr_list[0];
uint16_t seq = 1;
sighandler_t ret = signal(SIGINT, [](int) {
closing_statistics();
});
if (ret == SIG_ERR) {
perror("failed to install SIGINT handler");
return 1;
}
for (;;) {
auto ping_packet_result = ByteBuffer::create_zeroed(sizeof(struct icmphdr) + payload_size);
if (ping_packet_result.is_error()) {
warnln("failed to allocate a large enough buffer for the ping packet");
return 1;
}
auto& ping_packet = ping_packet_result.value();
struct icmphdr* ping_hdr = reinterpret_cast<struct icmphdr*>(ping_packet.data());
ping_hdr->type = ICMP_ECHO;
ping_hdr->code = 0;
ping_hdr->un.echo.id = htons(pid);
ping_hdr->un.echo.sequence = htons(seq++);
// Fill payload
for (int i = 0; i < payload_size; i++) {
ping_packet[i + sizeof(struct icmphdr)] = i & 0xFF;
}
ping_hdr->checksum = internet_checksum(ping_packet.data(), ping_packet.size());
struct timeval tv_send;
gettimeofday(&tv_send, nullptr);
rc = sendto(fd, ping_packet.data(), ping_packet.size(), 0, (const struct sockaddr*)&peer_address, sizeof(sockaddr_in));
if (rc < 0) {
perror("sendto");
return 1;
}
if (count && total_pings == count)
closing_statistics();
else
total_pings++;
for (;;) {
auto pong_packet_result = ByteBuffer::create_uninitialized(
sizeof(struct ip) + max_optional_header_size_in_bytes + sizeof(struct icmphdr) + payload_size);
if (pong_packet_result.is_error()) {
warnln("failed to allocate a large enough buffer for the pong packet");
return 1;
}
auto& pong_packet = pong_packet_result.value();
socklen_t peer_address_size = sizeof(peer_address);
rc = recvfrom(fd, pong_packet.data(), pong_packet.size(), 0, (struct sockaddr*)&peer_address, &peer_address_size);
if (rc < 0) {
if (errno == EAGAIN) {
outln("Request (seq={}) timed out.", ntohs(ping_hdr->un.echo.sequence));
break;
}
perror("recvfrom");
return 1;
}
i8 internet_header_length = *pong_packet.data() & 0x0F;
if (internet_header_length < min_header_size_in_bytes) {
outln("ping: illegal ihl field value {:x}", internet_header_length);
continue;
}
struct icmphdr* pong_hdr = reinterpret_cast<struct icmphdr*>(pong_packet.data() + (internet_header_length * 4));
if (pong_hdr->type != ICMP_ECHOREPLY)
continue;
if (pong_hdr->code != 0)
continue;
if (ntohs(pong_hdr->un.echo.id) != pid)
continue;
struct timeval tv_receive;
gettimeofday(&tv_receive, nullptr);
struct timeval tv_diff;
timersub(&tv_receive, &tv_send, &tv_diff);
int ms = tv_diff.tv_sec * 1000 + tv_diff.tv_usec / 1000;
successful_pings++;
int seq_dif = ntohs(ping_hdr->un.echo.sequence) - ntohs(pong_hdr->un.echo.sequence);
// Approximation about the timeout of the out of order packet
if (seq_dif)
ms += seq_dif * 1000 * timeout.tv_sec;
total_ms += ms;
if (min_ms == 0)
min_ms = max_ms = ms;
else if (ms < min_ms)
min_ms = ms;
else if (ms > max_ms)
max_ms = ms;
char addr_buf[INET_ADDRSTRLEN];
outln("Pong from {}: id={}, seq={}{}, time={}ms, size={}",
inet_ntop(AF_INET, &peer_address.sin_addr, addr_buf, sizeof(addr_buf)),
ntohs(pong_hdr->un.echo.id),
ntohs(pong_hdr->un.echo.sequence),
pong_hdr->un.echo.sequence != ping_hdr->un.echo.sequence ? "(!)" : "",
ms, rc);
// If this was a response to an earlier packet, we still need to wait for the current one.
if (pong_hdr->un.echo.sequence != ping_hdr->un.echo.sequence)
continue;
break;
}
sleep(1);
}
}
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