1 files changed, 280 insertions, 0 deletions
diff --git a/src/hid_openbsd.c b/src/hid_openbsd.c
new file mode 100644
index 0000000..2d08aca
--- /dev/null
+++ b/src/hid_openbsd.c
@@ -0,0 +1,280 @@
+/*
+ * Copyright (c) 2019 Google LLC. All rights reserved.
+ * Use of this source code is governed by a BSD-style
+ * license that can be found in the LICENSE file.
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <sys/types.h>
+
+#include <sys/ioctl.h>
+#include <dev/usb/usb.h>
+
+#include <errno.h>
+#include <fcntl.h>
+#include <poll.h>
+#include <signal.h>
+#include <unistd.h>
+
+#include "fido.h"
+
+#define MAX_UHID	64
+
+struct hid_openbsd {
+	int fd;
+	size_t report_in_len;
+	size_t report_out_len;
+	sigset_t sigmask;
+	const sigset_t *sigmaskp;
+};
+
+static int
+copy_info(fido_dev_info_t *di, const char *path)
+{
+	int fd = -1, ok = -1;
+	struct usb_device_info udi;
+
+	memset(di, 0, sizeof(*di));
+	memset(&udi, 0, sizeof(udi));
+
+	if ((fd = fido_hid_unix_open(path)) == -1)
+		goto fail;
+	if (ioctl(fd, IOCTL_REQ(USB_GET_DEVICEINFO), &udi) == -1) {
+		fido_log_error(errno, "%s: ioctl %s", __func__, path);
+		goto fail;
+	}
+
+	fido_log_debug("%s: %s: bus = 0x%02x, addr = 0x%02x", __func__, path,
+	    udi.udi_bus, udi.udi_addr);
+	fido_log_debug("%s: %s: vendor = \"%s\", product = \"%s\"", __func__,
+	    path, udi.udi_vendor, udi.udi_product);
+	fido_log_debug("%s: %s: productNo = 0x%04x, vendorNo = 0x%04x, "
+	    "releaseNo = 0x%04x", __func__, path, udi.udi_productNo,
+	    udi.udi_vendorNo, udi.udi_releaseNo);
+
+	if ((di->path = strdup(path)) == NULL ||
+	    (di->manufacturer = strdup(udi.udi_vendor)) == NULL ||
+	    (di->product = strdup(udi.udi_product)) == NULL)
+		goto fail;
+
+	di->vendor_id = (int16_t)udi.udi_vendorNo;
+	di->product_id = (int16_t)udi.udi_productNo;
+
+	ok = 0;
+fail:
+	if (fd != -1 && close(fd) == -1)
+		fido_log_error(errno, "%s: close %s", __func__, path);
+
+	if (ok < 0) {
+		free(di->path);
+		free(di->manufacturer);
+		free(di->product);
+		explicit_bzero(di, sizeof(*di));
+	}
+
+	return (ok);
+}
+
+int
+fido_hid_manifest(fido_dev_info_t *devlist, size_t ilen, size_t *olen)
+{
+	size_t i;
+	char path[64];
+
+	if (ilen == 0)
+		return (FIDO_OK); /* nothing to do */
+
+	if (devlist == NULL || olen == NULL)
+		return (FIDO_ERR_INVALID_ARGUMENT);
+
+	for (i = *olen = 0; i < MAX_UHID && *olen < ilen; i++) {
+		snprintf(path, sizeof(path), "/dev/fido/%zu", i);
+		if (copy_info(&devlist[*olen], path) == 0) {
+			devlist[*olen].io = (fido_dev_io_t) {
+				fido_hid_open,
+				fido_hid_close,
+				fido_hid_read,
+				fido_hid_write,
+			};
+			++(*olen);
+		}
+	}
+
+	return (FIDO_OK);
+}
+
+/*
+ * Workaround for OpenBSD <=6.6-current (as of 201910) bug that loses
+ * sync of DATA0/DATA1 sequence bit across uhid open/close.
+ * Send pings until we get a response - early pings with incorrect
+ * sequence bits will be ignored as duplicate packets by the device.
+ */
+static int
+terrible_ping_kludge(struct hid_openbsd *ctx)
+{
+	u_char data[256];
+	int i, n;
+	struct pollfd pfd;
+
+	if (sizeof(data) < ctx->report_out_len + 1)
+		return -1;
+	for (i = 0; i < 4; i++) {
+		memset(data, 0, sizeof(data));
+		/* broadcast channel ID */
+		data[1] = 0xff;
+		data[2] = 0xff;
+		data[3] = 0xff;
+		data[4] = 0xff;
+		/* Ping command */
+		data[5] = 0x81;
+		/* One byte ping only, Vasili */
+		data[6] = 0;
+		data[7] = 1;
+		fido_log_debug("%s: send ping %d", __func__, i);
+		if (fido_hid_write(ctx, data, ctx->report_out_len + 1) == -1)
+			return -1;
+		fido_log_debug("%s: wait reply", __func__);
+		memset(&pfd, 0, sizeof(pfd));
+		pfd.fd = ctx->fd;
+		pfd.events = POLLIN;
+		if ((n = poll(&pfd, 1, 100)) == -1) {
+			fido_log_error(errno, "%s: poll", __func__);
+			return -1;
+		} else if (n == 0) {
+			fido_log_debug("%s: timed out", __func__);
+			continue;
+		}
+		if (fido_hid_read(ctx, data, ctx->report_out_len, 250) == -1)
+			return -1;
+		/*
+		 * Ping isn't always supported on the broadcast channel,
+		 * so we might get an error, but we don't care - we're
+		 * synched now.
+		 */
+		fido_log_xxd(data, ctx->report_out_len, "%s: got reply",
+		    __func__);
+		return 0;
+	}
+	fido_log_debug("%s: no response", __func__);
+	return -1;
+}
+
+void *
+fido_hid_open(const char *path)
+{
+	struct hid_openbsd *ret = NULL;
+
+	if ((ret = calloc(1, sizeof(*ret))) == NULL ||
+	    (ret->fd = fido_hid_unix_open(path)) == -1) {
+		free(ret);
+		return (NULL);
+	}
+	ret->report_in_len = ret->report_out_len = CTAP_MAX_REPORT_LEN;
+	fido_log_debug("%s: inlen = %zu outlen = %zu", __func__,
+	    ret->report_in_len, ret->report_out_len);
+
+	/*
+	 * OpenBSD (as of 201910) has a bug that causes it to lose
+	 * track of the DATA0/DATA1 sequence toggle across uhid device
+	 * open and close. This is a terrible hack to work around it.
+	 */
+	if (terrible_ping_kludge(ret) != 0) {
+		fido_hid_close(ret);
+		return NULL;
+	}
+
+	return (ret);
+}
+
+void
+fido_hid_close(void *handle)
+{
+	struct hid_openbsd *ctx = (struct hid_openbsd *)handle;
+
+	if (close(ctx->fd) == -1)
+		fido_log_error(errno, "%s: close", __func__);
+
+	free(ctx);
+}
+
+int
+fido_hid_set_sigmask(void *handle, const fido_sigset_t *sigmask)
+{
+	struct hid_openbsd *ctx = handle;
+
+	ctx->sigmask = *sigmask;
+	ctx->sigmaskp = &ctx->sigmask;
+
+	return (FIDO_OK);
+}
+
+int
+fido_hid_read(void *handle, unsigned char *buf, size_t len, int ms)
+{
+	struct hid_openbsd *ctx = (struct hid_openbsd *)handle;
+	ssize_t r;
+
+	if (len != ctx->report_in_len) {
+		fido_log_debug("%s: invalid len: got %zu, want %zu", __func__,
+		    len, ctx->report_in_len);
+		return (-1);
+	}
+
+	if (fido_hid_unix_wait(ctx->fd, ms, ctx->sigmaskp) < 0) {
+		fido_log_debug("%s: fd not ready", __func__);
+		return (-1);
+	}
+
+	if ((r = read(ctx->fd, buf, len)) == -1) {
+		fido_log_error(errno, "%s: read", __func__);
+		return (-1);
+	}
+
+	if (r < 0 || (size_t)r != len) {
+		fido_log_debug("%s: %zd != %zu", __func__, r, len);
+		return (-1);
+	}
+
+	return ((int)len);
+}
+
+int
+fido_hid_write(void *handle, const unsigned char *buf, size_t len)
+{
+	struct hid_openbsd *ctx = (struct hid_openbsd *)handle;
+	ssize_t r;
+
+	if (len != ctx->report_out_len + 1) {
+		fido_log_debug("%s: invalid len: got %zu, want %zu", __func__,
+		    len, ctx->report_out_len);
+		return (-1);
+	}
+
+	if ((r = write(ctx->fd, buf + 1, len - 1)) == -1) {
+		fido_log_error(errno, "%s: write", __func__);
+		return (-1);
+	}
+
+	if (r < 0 || (size_t)r != len - 1) {
+		fido_log_debug("%s: %zd != %zu", __func__, r, len - 1);
+		return (-1);
+	}
+
+	return ((int)len);
+}
+
+size_t
+fido_hid_report_in_len(void *handle)
+{
+	struct hid_openbsd *ctx = handle;
+
+	return (ctx->report_in_len);
+}
+
+size_t
+fido_hid_report_out_len(void *handle)
+{
+	struct hid_openbsd *ctx = handle;
+
+	return (ctx->report_out_len);
+}