4 files changed, 128 insertions, 4 deletions

diff --git a/src/cmd/init/init.c b/src/cmd/init/init.c
index d8cb1f4..68268bf 100644
--- a/src/cmd/init/init.c
+++ b/src/cmd/init/init.c
@@ -129,6 +129,13 @@ int main(void) {
 		MOUNT_AT("/") { fs_whitelist(allow); }
 		execv(argv[0], (void*)argv);
 	}
+	MOUNT_AT("/dev/ntp") {
+		const char *allow[] = {"/bin/ntpfs", "/net/connect/", NULL};
+		const char *argv[] = {"/bin/ntpfs", "/net/connect/0/10.69.0.1/udp/123", NULL};
+		MOUNT_AT("/") { fs_whitelist(allow); }
+		_sys_sleep(1000); /* hack, waits until the network goes up */
+		execv(argv[0], (void*)argv);
+	}
 
 	if (!fork()) {
 		redirect("/bin/shell", "/dev/com1", "/dev/com1");
diff --git a/src/cmd/netstack/udp.c b/src/cmd/netstack/udp.c
index 285af41..3b53b47 100644
--- a/src/cmd/netstack/udp.c
+++ b/src/cmd/netstack/udp.c
@@ -55,10 +55,13 @@ struct udp_conn *udpc_new(
 	c->lport = u.src ? u.src : 50000; // TODO randomize source ports
 	c->rport = u.dst;
 	if (arpcache_get(c->rip, &c->rmac) < 0) {
-		// TODO make arp request, wait for reply
-		warnx("IP not in ARP cache, unimplemented");
-		free(c);
-		return NULL;
+		// TODO wait for ARP reply
+		arp_request(c->rip);
+		if (arpcache_get(state.gateway, &c->rmac) < 0) {
+			warnx("neither target nor gateway not in ARP cache, dropping");
+			free(c);
+			return NULL;
+		}
 	}
 	c->on_recv = on_recv;
 	c->carg = carg;
diff --git a/src/cmd/netstack/util.h b/src/cmd/netstack/util.h
index c1032a2..1cd22fb 100644
--- a/src/cmd/netstack/util.h
+++ b/src/cmd/netstack/util.h
@@ -40,3 +40,15 @@ static inline uint32_t nget32(const void *vbuf) {
 	     | (b[2] <<  8)
 	     | (b[3] <<  0);
 }
+
+static inline uint64_t nget64(const void *vbuf) {
+	const uint8_t *b = vbuf;
+	return ((uint64_t)b[0] << 56)
+	     | ((uint64_t)b[1] << 48)
+	     | ((uint64_t)b[2] << 40)
+	     | ((uint64_t)b[3] << 32)
+	     | ((uint64_t)b[4] << 24)
+	     | ((uint64_t)b[5] << 16)
+	     | ((uint64_t)b[6] <<  8)
+	     | ((uint64_t)b[7] <<  0);
+}
diff --git a/src/cmd/ntpfs.c b/src/cmd/ntpfs.c
new file mode 100644
index 0000000..783b56e
--- /dev/null
+++ b/src/cmd/ntpfs.c
@@ -0,0 +1,102 @@
+#include <camellia.h>
+#include <camellia/flags.h>
+#include <camellia/fs/misc.h>
+#include <camellia/fsutil.h>
+#include <camellia/syscalls.h>
+#include <err.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <unistd.h>
+
+// TODO put that in the libc somewhere
+#include "netstack/util.h"
+
+enum {
+	PacketSize = 12 * 4, /* 12 words */
+	ClientMode = 3,
+	NtpV4 = 4 << 3,
+	TxTimestamp = 40,
+};
+
+uint64_t offset = 0;
+
+uint64_t
+getntptime(const char *addr)
+{
+	char packet[PacketSize] = {0};
+	packet[0] |= ClientMode;
+	packet[0] |= NtpV4;
+
+	hid_t h = camellia_open(addr, OPEN_READ | OPEN_WRITE);
+	if (h < 0) {
+		warn("open %s", addr);
+		return 0;
+	}
+	if (write(h, packet, PacketSize) != PacketSize) {
+		warnx("partial write");
+		close(h);
+		return 0;
+	}
+	ssize_t ret = read(h, packet, PacketSize);
+	if (ret != PacketSize) {
+		warnx("partial read");
+		close(h);
+		return 0;
+	}
+
+	return nget64(packet + TxTimestamp);
+}
+
+/* Converts an NTP timestamp to the amount of nanoseconds (10^-9) since the
+ * Unix epoch. */
+uint64_t
+ntp2unix(uint64_t ntp)
+{
+	uint64_t seconds = (ntp >> 32) - 2208988800;
+	uint64_t frac = ntp & 0xFFFFFFFF;
+	uint64_t prec = 1000000000;
+	return seconds * prec + ((frac * prec) >> 32);
+}
+
+int
+main(int argc, const char *argv[])
+{
+	if (argc != 2) {
+		errx(1, "bad usage");
+	}
+
+	// TODO: error checking, once i actually implement timeouts
+	uint64_t ntpt = getntptime(argv[1]);
+	uint64_t unixt = ntp2unix(ntpt);
+	offset = unixt - _sys_time(0);
+
+	char buf[256];
+	int len;
+
+	struct ufs_request req;
+	hid_t reqh;
+	while ((reqh = ufs_wait(buf, sizeof(buf), &req))) {
+		switch (req.op) {
+		case VFSOP_OPEN:
+			if (req.len == 0 && !OPEN_WRITEABLE(req.flags)) {
+				_sys_fs_respond(reqh, NULL, 0, 0);
+			} else {
+				_sys_fs_respond(reqh, NULL, -EGENERIC, 0);
+			}
+			break;
+		case VFSOP_READ:
+			len = snprintf(buf, sizeof(buf), "%lu\n", _sys_time(0) + offset);
+			if (0 <= len && len < (int)sizeof(buf)) {
+				fs_normslice(&req.offset, &req.len, len, false);
+				_sys_fs_respond(reqh, buf + req.offset, req.len, 0);
+			} else {
+				_sys_fs_respond(reqh, NULL, -EGENERIC, 0);
+			}
+			break;
+		default:
+			_sys_fs_respond(reqh, NULL, -ENOSYS, 0);
+			break;
+		}
+	}
+}