/libfido2/src/nfc_linux.c
Line | Count | Source (jump to first uncovered line) |
1 | | /* |
2 | | * Copyright (c) 2020-2022 Yubico AB. All rights reserved. |
3 | | * Use of this source code is governed by a BSD-style |
4 | | * license that can be found in the LICENSE file. |
5 | | * SPDX-License-Identifier: BSD-2-Clause |
6 | | */ |
7 | | |
8 | | #include <sys/types.h> |
9 | | #include <sys/uio.h> |
10 | | #include <sys/socket.h> |
11 | | |
12 | | #include <linux/nfc.h> |
13 | | |
14 | | #include <errno.h> |
15 | | #include <libudev.h> |
16 | | #include <signal.h> |
17 | | #include <stdio.h> |
18 | | #include <string.h> |
19 | | #include <unistd.h> |
20 | | |
21 | | #include "fido.h" |
22 | | #include "fido/param.h" |
23 | | #include "netlink.h" |
24 | | #include "iso7816.h" |
25 | | |
26 | | struct nfc_linux { |
27 | | int fd; |
28 | | uint32_t dev; |
29 | | uint32_t target; |
30 | | sigset_t sigmask; |
31 | | const sigset_t *sigmaskp; |
32 | | struct fido_nl *nl; |
33 | | }; |
34 | | |
35 | | static char * |
36 | | get_parent_attr(struct udev_device *dev, const char *subsystem, |
37 | | const char *devtype, const char *attr) |
38 | 0 | { |
39 | 0 | struct udev_device *parent; |
40 | 0 | const char *value; |
41 | |
|
42 | 0 | if ((parent = udev_device_get_parent_with_subsystem_devtype(dev, |
43 | 0 | subsystem, devtype)) == NULL || (value = |
44 | 0 | udev_device_get_sysattr_value(parent, attr)) == NULL) |
45 | 0 | return NULL; |
46 | | |
47 | 0 | return strdup(value); |
48 | 0 | } |
49 | | |
50 | | static char * |
51 | | get_usb_attr(struct udev_device *dev, const char *attr) |
52 | 0 | { |
53 | 0 | return get_parent_attr(dev, "usb", "usb_device", attr); |
54 | 0 | } |
55 | | |
56 | | static int |
57 | | copy_info(fido_dev_info_t *di, struct udev *udev, |
58 | | struct udev_list_entry *udev_entry) |
59 | 557k | { |
60 | 557k | const char *name; |
61 | 557k | char *str; |
62 | 557k | struct udev_device *dev = NULL; |
63 | 557k | uint64_t id; |
64 | 557k | int ok = -1; |
65 | | |
66 | 557k | memset(di, 0, sizeof(*di)); |
67 | | |
68 | 557k | if ((name = udev_list_entry_get_name(udev_entry)) == NULL || |
69 | 557k | (dev = udev_device_new_from_syspath(udev, name)) == NULL) |
70 | 2.71k | goto fail; |
71 | 554k | if (asprintf(&di->path, "%s/%s", FIDO_NFC_PREFIX, name) == -1) { |
72 | 1.39k | di->path = NULL; |
73 | 1.39k | goto fail; |
74 | 1.39k | } |
75 | 553k | if (nfc_is_fido(di->path) == false) { |
76 | 553k | fido_log_debug("%s: nfc_is_fido: %s", __func__, di->path); |
77 | 553k | goto fail; |
78 | 553k | } |
79 | 0 | if ((di->manufacturer = get_usb_attr(dev, "manufacturer")) == NULL) |
80 | 0 | di->manufacturer = strdup(""); |
81 | 0 | if ((di->product = get_usb_attr(dev, "product")) == NULL) |
82 | 0 | di->product = strdup(""); |
83 | 0 | if (di->manufacturer == NULL || di->product == NULL) |
84 | 0 | goto fail; |
85 | | /* XXX assumes USB for vendor/product info */ |
86 | 0 | if ((str = get_usb_attr(dev, "idVendor")) != NULL && |
87 | 0 | fido_to_uint64(str, 16, &id) == 0 && id <= UINT16_MAX) |
88 | 0 | di->vendor_id = (int16_t)id; |
89 | 0 | free(str); |
90 | 0 | if ((str = get_usb_attr(dev, "idProduct")) != NULL && |
91 | 0 | fido_to_uint64(str, 16, &id) == 0 && id <= UINT16_MAX) |
92 | 0 | di->product_id = (int16_t)id; |
93 | 0 | free(str); |
94 | |
|
95 | 0 | ok = 0; |
96 | 557k | fail: |
97 | 557k | if (dev != NULL) |
98 | 554k | udev_device_unref(dev); |
99 | | |
100 | 557k | if (ok < 0) { |
101 | 557k | free(di->path); |
102 | 557k | free(di->manufacturer); |
103 | 557k | free(di->product); |
104 | 557k | explicit_bzero(di, sizeof(*di)); |
105 | 557k | } |
106 | | |
107 | 557k | return ok; |
108 | 0 | } |
109 | | |
110 | | static int |
111 | | sysnum_from_syspath(const char *path) |
112 | 550k | { |
113 | 550k | struct udev *udev = NULL; |
114 | 550k | struct udev_device *dev = NULL; |
115 | 550k | const char *str; |
116 | 550k | uint64_t idx64; |
117 | 550k | int idx = -1; |
118 | | |
119 | 550k | if ((udev = udev_new()) != NULL && |
120 | 550k | (dev = udev_device_new_from_syspath(udev, path)) != NULL && |
121 | 550k | (str = udev_device_get_sysnum(dev)) != NULL && |
122 | 550k | fido_to_uint64(str, 10, &idx64) == 0 && idx64 < INT_MAX) |
123 | 546k | idx = (int)idx64; |
124 | | |
125 | 550k | if (dev != NULL) |
126 | 547k | udev_device_unref(dev); |
127 | 550k | if (udev != NULL) |
128 | 549k | udev_unref(udev); |
129 | | |
130 | 550k | return idx; |
131 | 550k | } |
132 | | |
133 | | int |
134 | | fido_nfc_manifest(fido_dev_info_t *devlist, size_t ilen, size_t *olen) |
135 | 1.17k | { |
136 | 1.17k | struct udev *udev = NULL; |
137 | 1.17k | struct udev_enumerate *udev_enum = NULL; |
138 | 1.17k | struct udev_list_entry *udev_list; |
139 | 1.17k | struct udev_list_entry *udev_entry; |
140 | 1.17k | int r = FIDO_ERR_INTERNAL; |
141 | | |
142 | 1.17k | *olen = 0; |
143 | | |
144 | 1.17k | if (ilen == 0) |
145 | 0 | return FIDO_OK; |
146 | | |
147 | 1.17k | if (devlist == NULL) |
148 | 0 | return FIDO_ERR_INVALID_ARGUMENT; |
149 | | |
150 | 1.17k | if ((udev = udev_new()) == NULL || |
151 | 1.17k | (udev_enum = udev_enumerate_new(udev)) == NULL) |
152 | 9 | goto fail; |
153 | | |
154 | 1.16k | if (udev_enumerate_add_match_subsystem(udev_enum, "nfc") < 0 || |
155 | 1.16k | udev_enumerate_scan_devices(udev_enum) < 0) |
156 | 9 | goto fail; |
157 | | |
158 | 1.15k | if ((udev_list = udev_enumerate_get_list_entry(udev_enum)) == NULL) { |
159 | 2 | r = FIDO_OK; /* zero nfc devices */ |
160 | 2 | goto fail; |
161 | 2 | } |
162 | | |
163 | 557k | udev_list_entry_foreach(udev_entry, udev_list) { |
164 | 557k | if (copy_info(&devlist[*olen], udev, udev_entry) == 0) { |
165 | 0 | devlist[*olen].io = (fido_dev_io_t) { |
166 | 0 | fido_nfc_open, |
167 | 0 | fido_nfc_close, |
168 | 0 | fido_nfc_read, |
169 | 0 | fido_nfc_write, |
170 | 0 | }; |
171 | 0 | devlist[*olen].transport = (fido_dev_transport_t) { |
172 | 0 | fido_nfc_rx, |
173 | 0 | fido_nfc_tx, |
174 | 0 | }; |
175 | 0 | if (++(*olen) == ilen) |
176 | 0 | break; |
177 | 0 | } |
178 | 557k | } |
179 | | |
180 | 1.15k | r = FIDO_OK; |
181 | 1.17k | fail: |
182 | 1.17k | if (udev_enum != NULL) |
183 | 1.16k | udev_enumerate_unref(udev_enum); |
184 | 1.17k | if (udev != NULL) |
185 | 1.17k | udev_unref(udev); |
186 | | |
187 | 1.17k | return r; |
188 | 1.15k | } |
189 | | |
190 | | static int |
191 | | nfc_target_connect(struct nfc_linux *ctx) |
192 | 0 | { |
193 | 0 | struct sockaddr_nfc sa; |
194 | |
|
195 | 0 | memset(&sa, 0, sizeof(sa)); |
196 | 0 | sa.sa_family = AF_NFC; |
197 | 0 | sa.dev_idx = ctx->dev; |
198 | 0 | sa.target_idx = ctx->target; |
199 | 0 | sa.nfc_protocol = NFC_PROTO_ISO14443; |
200 | |
|
201 | 0 | if ((ctx->fd = socket(AF_NFC, SOCK_SEQPACKET | SOCK_CLOEXEC, |
202 | 0 | NFC_SOCKPROTO_RAW)) == -1) { |
203 | 0 | fido_log_error(errno, "%s: socket", __func__); |
204 | 0 | return -1; |
205 | 0 | } |
206 | 0 | if (connect(ctx->fd, (struct sockaddr *)&sa, sizeof(sa)) == -1) { |
207 | 0 | fido_log_error(errno, "%s: connect", __func__); |
208 | 0 | if (close(ctx->fd) == -1) |
209 | 0 | fido_log_error(errno, "%s: close", __func__); |
210 | 0 | ctx->fd = -1; |
211 | 0 | return -1; |
212 | 0 | } |
213 | | |
214 | 0 | return 0; |
215 | 0 | } |
216 | | |
217 | | static void |
218 | | nfc_free(struct nfc_linux **ctx_p) |
219 | 1.09M | { |
220 | 1.09M | struct nfc_linux *ctx; |
221 | | |
222 | 1.09M | if (ctx_p == NULL || (ctx = *ctx_p) == NULL) |
223 | 551k | return; |
224 | 545k | if (ctx->fd != -1 && close(ctx->fd) == -1) |
225 | 544k | fido_log_error(errno, "%s: close", __func__); |
226 | 545k | if (ctx->nl != NULL) |
227 | 353 | fido_nl_free(&ctx->nl); |
228 | | |
229 | 545k | free(ctx); |
230 | 545k | *ctx_p = NULL; |
231 | 545k | } |
232 | | |
233 | | static struct nfc_linux * |
234 | | nfc_new(uint32_t dev) |
235 | 546k | { |
236 | 546k | struct nfc_linux *ctx; |
237 | | |
238 | 546k | if ((ctx = calloc(1, sizeof(*ctx))) == NULL || |
239 | 546k | (ctx->nl = fido_nl_new()) == NULL) { |
240 | 546k | nfc_free(&ctx); |
241 | 546k | return NULL; |
242 | 546k | } |
243 | | |
244 | 353 | ctx->fd = -1; |
245 | 353 | ctx->dev = dev; |
246 | | |
247 | 353 | return ctx; |
248 | 546k | } |
249 | | |
250 | | void * |
251 | | fido_nfc_open(const char *path) |
252 | 550k | { |
253 | 550k | struct nfc_linux *ctx = NULL; |
254 | 550k | int idx; |
255 | | |
256 | 550k | if (strncmp(path, FIDO_NFC_PREFIX, strlen(FIDO_NFC_PREFIX)) != 0) { |
257 | 0 | fido_log_debug("%s: bad prefix", __func__); |
258 | 0 | goto fail; |
259 | 0 | } |
260 | 550k | if ((idx = sysnum_from_syspath(path + strlen(FIDO_NFC_PREFIX))) < 0 || |
261 | 550k | (ctx = nfc_new((uint32_t)idx)) == NULL) { |
262 | 550k | fido_log_debug("%s: nfc_new", __func__); |
263 | 550k | goto fail; |
264 | 550k | } |
265 | 353 | if (fido_nl_power_nfc(ctx->nl, ctx->dev) < 0 || |
266 | 353 | fido_nl_get_nfc_target(ctx->nl, ctx->dev, &ctx->target) < 0 || |
267 | 353 | nfc_target_connect(ctx) < 0) { |
268 | 353 | fido_log_debug("%s: netlink", __func__); |
269 | 353 | goto fail; |
270 | 353 | } |
271 | | |
272 | 0 | return ctx; |
273 | 550k | fail: |
274 | 550k | nfc_free(&ctx); |
275 | 550k | return NULL; |
276 | 353 | } |
277 | | |
278 | | void |
279 | | fido_nfc_close(void *handle) |
280 | 0 | { |
281 | 0 | struct nfc_linux *ctx = handle; |
282 | |
|
283 | 0 | nfc_free(&ctx); |
284 | 0 | } |
285 | | |
286 | | int |
287 | | fido_nfc_set_sigmask(void *handle, const fido_sigset_t *sigmask) |
288 | 0 | { |
289 | 0 | struct nfc_linux *ctx = handle; |
290 | |
|
291 | 0 | ctx->sigmask = *sigmask; |
292 | 0 | ctx->sigmaskp = &ctx->sigmask; |
293 | |
|
294 | 0 | return FIDO_OK; |
295 | 0 | } |
296 | | |
297 | | int |
298 | | fido_nfc_read(void *handle, unsigned char *buf, size_t len, int ms) |
299 | 0 | { |
300 | 0 | struct nfc_linux *ctx = handle; |
301 | 0 | struct iovec iov[2]; |
302 | 0 | uint8_t preamble; |
303 | 0 | ssize_t r; |
304 | |
|
305 | 0 | memset(&iov, 0, sizeof(iov)); |
306 | 0 | iov[0].iov_base = &preamble; |
307 | 0 | iov[0].iov_len = sizeof(preamble); |
308 | 0 | iov[1].iov_base = buf; |
309 | 0 | iov[1].iov_len = len; |
310 | |
|
311 | 0 | if (fido_hid_unix_wait(ctx->fd, ms, ctx->sigmaskp) < 0) { |
312 | 0 | fido_log_debug("%s: fido_hid_unix_wait", __func__); |
313 | 0 | return -1; |
314 | 0 | } |
315 | 0 | if ((r = readv(ctx->fd, iov, nitems(iov))) == -1) { |
316 | 0 | fido_log_error(errno, "%s: read", __func__); |
317 | 0 | return -1; |
318 | 0 | } |
319 | 0 | if (r < 1) { |
320 | 0 | fido_log_debug("%s: %zd < 1", __func__, r); |
321 | 0 | return -1; |
322 | 0 | } |
323 | 0 | if (preamble != 0x00) { |
324 | 0 | fido_log_debug("%s: preamble", __func__); |
325 | 0 | return -1; |
326 | 0 | } |
327 | | |
328 | 0 | r--; |
329 | 0 | fido_log_xxd(buf, (size_t)r, "%s", __func__); |
330 | |
|
331 | 0 | return (int)r; |
332 | 0 | } |
333 | | |
334 | | int |
335 | | fido_nfc_write(void *handle, const unsigned char *buf, size_t len) |
336 | 0 | { |
337 | 0 | struct nfc_linux *ctx = handle; |
338 | 0 | ssize_t r; |
339 | |
|
340 | 0 | fido_log_xxd(buf, len, "%s", __func__); |
341 | |
|
342 | 0 | if (len > INT_MAX) { |
343 | 0 | fido_log_debug("%s: len", __func__); |
344 | 0 | return -1; |
345 | 0 | } |
346 | 0 | if ((r = write(ctx->fd, buf, len)) == -1) { |
347 | 0 | fido_log_error(errno, "%s: write", __func__); |
348 | 0 | return -1; |
349 | 0 | } |
350 | 0 | if (r < 0 || (size_t)r != len) { |
351 | 0 | fido_log_debug("%s: %zd != %zu", __func__, r, len); |
352 | 0 | return -1; |
353 | 0 | } |
354 | | |
355 | 0 | return (int)r; |
356 | 0 | } |