Add ping(8).

Makefile

@@ -25,6 +25,7 @@ kblayout \
 kblayout-compiler \
 login \
 mkinitrd \
+ping \
 regress \
 rw \
 sf \

ping/.gitignore

@@ -0,0 +1 @@
+ping

ping/Makefile

@@ -0,0 +1,29 @@
+SOFTWARE_MEANT_FOR_SORTIX=1
+include ../build-aux/platform.mak
+include ../build-aux/compiler.mak
+include ../build-aux/version.mak
+include ../build-aux/dirs.mak
+
+OPTLEVEL?=$(DEFAULT_OPTLEVEL)
+CFLAGS?=$(OPTLEVEL)
+
+CFLAGS += -Wall -Wextra
+
+BINARIES = ping
+#MANPAGES8 = ping.8
+
+all: $(BINARIES)
+
+.PHONY: all install clean
+
+install: all
+	mkdir -p $(DESTDIR)$(SBINDIR)
+	install $(BINARIES) $(DESTDIR)$(SBINDIR)
+	#mkdir -p $(DESTDIR)$(MANDIR)/man8
+	#install $(MANPAGES8) $(DESTDIR)$(MANDIR)/man8
+
+%: %.c
+	$(CC) -std=gnu11 $(CFLAGS) $(CPPFLAGS) $< -o $@
+
+clean:
+	rm -f $(BINARIES)

ping/ping.c

@@ -0,0 +1,180 @@
+/*
+ * Copyright (c) 2017 Jonas 'Sortie' Termansen.
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ * ping.c
+ * Internet Control Message Protocol Echo.
+ */
+
+#include <sys/socket.h>
+
+#include <err.h>
+#include <netdb.h>
+#include <netinet/in.h>
+#include <poll.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <timespec.h>
+#include <unistd.h>
+
+#define PAYLOAD_SIZE 56
+
+static void compact_arguments(int* argc, char*** argv)
+{
+	for ( int i = 0; i < *argc; i++ )
+	{
+		while ( i < *argc && !(*argv)[i] )
+		{
+			for ( int n = i; n < *argc; n++ )
+				(*argv)[n] = (*argv)[n+1];
+			(*argc)--;
+		}
+	}
+}
+
+int main(int argc, char* argv[])
+{
+	bool ipv4 = false;
+	bool ipv6 = false;
+
+	for ( int i = 1; i < argc; i++ )
+	{
+		const char* arg = argv[i];
+		if ( arg[0] != '-' || !arg[1] )
+			continue;
+		argv[i] = NULL;
+		if ( !strcmp(arg, "--") )
+			break;
+		if ( arg[1] != '-' )
+		{
+			char c;
+			while ( (c = *++arg) ) switch ( c )
+			{
+			case '4': ipv4 = true; break;
+			case '6': ipv6 = true; break;
+			default:
+				errx(1, "unknown option -- '%c'", c);
+			}
+		}
+		else
+			errx(1, "unknown option: %s", arg);
+	}
+
+	compact_arguments(&argc, &argv);
+
+	if ( argc < 2 )
+		errx(1, "No host given");
+	const char* host = argv[1];
+	if ( 2 < argc )
+		errx(1, "Unexpected extra operand `%s'", argv[3]);
+
+	if ( 1 < ipv4 + ipv6 )
+		errx(1, "The -4 and -6 options are mutually incompatible");
+
+	struct addrinfo hint;
+	memset(&hint, 0, sizeof(hint));
+	if ( ipv4 )
+		hint.ai_family = AF_INET;
+	if ( ipv6 )
+		hint.ai_family = AF_INET6;
+	hint.ai_socktype = SOCK_DGRAM;
+	hint.ai_protocol = IPPROTO_PING;
+
+	struct addrinfo* res0 = NULL;
+	int status = getaddrinfo(host, NULL, &hint, &res0);
+	if ( status == EAI_SYSTEM )
+		err(1, "%s", host);
+	if ( status )
+		errx(1, "%s: %s", host, gai_strerror(status));
+	if ( !res0 )
+		errx(1, "%s: %s", host, gai_strerror(EAI_NONAME));
+
+	char host_address[NI_MAXHOST];
+	int fd;
+	for ( struct addrinfo* res = res0; res; res = res->ai_next )
+	{
+		if ( (fd = socket(res->ai_family, res->ai_socktype, res->ai_protocol)) < 0 )
+		{
+			if ( res->ai_next )
+				continue;
+			err(1, "socket");
+		}
+		if ( connect(fd, res->ai_addr, res->ai_addrlen) < 0 )
+		{
+			close(fd);
+			if ( res->ai_next )
+				continue;
+			err(1, "connect: %s", host);
+		}
+		if ( getnameinfo(res->ai_addr, res->ai_addrlen, host_address,
+		                 sizeof(host_address), NULL, 0, NI_NUMERICHOST) < 0 )
+			strlcpy(host_address, "unknown", sizeof(host_address));
+		break;
+	}
+
+	freeaddrinfo(res0);
+
+	printf("PING %s (%s) %zu bytes of data.\n",
+	       host, host_address, (size_t) (PAYLOAD_SIZE + 8));
+
+	while ( true )
+	{
+		unsigned char expected[PAYLOAD_SIZE];
+		arc4random_buf(expected, sizeof(expected));
+		struct timespec begun;
+		clock_gettime(CLOCK_MONOTONIC, &begun);
+		// TODO: Don't fail on network errors.
+		if ( send(fd, expected, sizeof(expected), 0) < 0 )
+			err(1, "send");
+		struct timespec timeout = timespec_add(timespec_make(1, 0), begun);
+		while ( true )
+		{
+			struct timespec now;
+			clock_gettime(CLOCK_MONOTONIC, &now);
+			struct timespec remaining = timespec_sub(timeout, now);
+			if ( remaining.tv_sec < 0 )
+				break;
+			struct pollfd pfd = { 0 };
+			pfd.fd = fd;
+			pfd.events = POLLIN;
+			if ( ppoll(&pfd, 1, &remaining, NULL) <= 0 )
+				break;
+			unsigned char gotten[PAYLOAD_SIZE];
+			ssize_t amount = recv(fd, gotten, sizeof(gotten), 0);
+			struct timespec end;
+			clock_gettime(CLOCK_MONOTONIC, &end);
+			// TODO: Don't fail on network errors.
+			if ( amount < 0 )
+				err(1, "recv");
+			if ( amount == PAYLOAD_SIZE &&
+				 memcmp(expected, gotten, PAYLOAD_SIZE) == 0 )
+			{
+				// TODO: Reverse DNS.
+				uint16_t sequence = gotten[0] << 8 | gotten[1] << 0;
+				struct timespec duration = timespec_sub(end, begun);
+				uintmax_t ms = (uintmax_t) duration.tv_sec * (uintmax_t) 1000 +
+						       (uintmax_t) ((duration.tv_nsec / 1000) / 1000);
+				unsigned int us = (duration.tv_nsec / 1000) % 1000;
+				printf("%zu bytes from %s (%s): icmp_seq=%u time=%ju.%03u ms\n",
+					   (size_t) (PAYLOAD_SIZE + 8), host, host_address,
+				       sequence, ms, us);
+			}
+		}
+	}
+
+	return 0;
+}

share/man/man4/ping.4

@@ -474,7 +474,8 @@ socket options was attempted to be set to a non-zero value.
 .Xr if 4 ,
 .Xr inet 4 ,
 .Xr ip 4 ,
-.Xr kernel 7
+.Xr kernel 7 ,
+.Xr ping 8
 .Sh STANDARDS
 .Rs
 .%A J. Postel (ed.)