ladybird/Userland/Utilities/arp.cpp
2021-11-08 00:35:27 +01:00

177 lines
5.1 KiB
C++

/*
* Copyright (c) 2020, the SerenityOS developers.
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/Assertions.h>
#include <AK/IPv4Address.h>
#include <AK/JsonObject.h>
#include <AK/MACAddress.h>
#include <AK/QuickSort.h>
#include <AK/String.h>
#include <AK/Types.h>
#include <LibCore/ArgsParser.h>
#include <LibCore/File.h>
#include <net/if_arp.h>
#include <net/route.h>
#include <netinet/in.h>
#include <string.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <unistd.h>
int main(int argc, char** argv)
{
if (pledge("stdio rpath tty", nullptr) < 0) {
perror("pledge");
return 1;
}
if (unveil("/proc/net/arp", "r") < 0) {
perror("unveil");
return 1;
}
if (unveil(nullptr, nullptr) < 0) {
perror("unveil");
return 1;
}
static bool flag_set;
static bool flag_delete;
const char* value_ipv4_address = nullptr;
const char* value_hw_address = nullptr;
Core::ArgsParser args_parser;
args_parser.set_general_help("Display or modify the system ARP cache");
args_parser.add_option(flag_set, "Set an ARP table entry", "set", 's');
args_parser.add_option(flag_delete, "Delete an ARP table entry", "delete", 'd');
args_parser.add_positional_argument(value_ipv4_address, "IPv4 protocol address", "address", Core::ArgsParser::Required::No);
args_parser.add_positional_argument(value_hw_address, "Hardware address", "hwaddress", Core::ArgsParser::Required::No);
args_parser.parse(argc, argv);
enum class Alignment {
Left,
Right
};
struct Column {
String title;
Alignment alignment { Alignment::Left };
int width { 0 };
String buffer;
};
Vector<Column> columns;
int proto_address_column = -1;
int hw_address_column = -1;
auto add_column = [&](auto title, auto alignment, auto width) {
columns.append({ title, alignment, width, {} });
return columns.size() - 1;
};
proto_address_column = add_column("Address", Alignment::Left, 15);
hw_address_column = add_column("HWaddress", Alignment::Left, 15);
auto print_column = [](auto& column, auto& string) {
if (!column.width) {
out("{}", string);
return;
}
if (column.alignment == Alignment::Right) {
out("{:>{1}} "sv, string, column.width);
} else {
out("{:<{1}} "sv, string, column.width);
}
};
for (auto& column : columns)
print_column(column, column.title);
outln();
if (!flag_set && !flag_delete) {
auto file = Core::File::construct("/proc/net/arp");
if (!file->open(Core::OpenMode::ReadOnly)) {
warnln("Failed to open {}: {}", file->name(), file->error_string());
return 1;
}
auto file_contents = file->read_all();
auto json = JsonValue::from_string(file_contents);
VERIFY(json.has_value());
Vector<JsonValue> sorted_regions = json.value().as_array().values();
quick_sort(sorted_regions, [](auto& a, auto& b) {
return a.as_object().get("ip_address").to_string() < b.as_object().get("ip_address").to_string();
});
for (auto& value : sorted_regions) {
auto& if_object = value.as_object();
auto ip_address = if_object.get("ip_address").to_string();
auto mac_address = if_object.get("mac_address").to_string();
if (proto_address_column != -1)
columns[proto_address_column].buffer = ip_address;
if (hw_address_column != -1)
columns[hw_address_column].buffer = mac_address;
for (auto& column : columns)
print_column(column, column.buffer);
outln();
};
}
if (flag_set || flag_delete) {
if (!value_ipv4_address || !value_hw_address) {
warnln("No protocol address or hardware address specified.");
return 1;
}
auto address = IPv4Address::from_string(value_ipv4_address);
if (!address.has_value()) {
warnln("Invalid IPv4 protocol address: '{}'", value_ipv4_address);
return 1;
}
auto hw_address = MACAddress::from_string(value_hw_address);
if (!hw_address.has_value()) {
warnln("Invalid MACAddress: '{}'", value_hw_address);
return 1;
}
int fd = socket(AF_INET, SOCK_DGRAM, IPPROTO_IP);
if (fd < 0) {
perror("socket");
return 1;
}
struct arpreq arp_req;
memset(&arp_req, 0, sizeof(arp_req));
arp_req.arp_pa.sa_family = AF_INET;
((sockaddr_in&)arp_req.arp_pa).sin_addr.s_addr = address.value().to_in_addr_t();
*(MACAddress*)&arp_req.arp_ha.sa_data[0] = hw_address.value();
int rc = 0;
if (flag_set)
rc = ioctl(fd, SIOCSARP, &arp_req);
if (flag_delete) {
int rc2 = ioctl(fd, SIOCDARP, &arp_req);
if (!rc2)
rc = rc2;
}
if (rc < 0) {
perror("ioctl");
return 1;
}
}
return 0;
}