/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 | | */ |
6 | | |
7 | | #include <sys/types.h> |
8 | | #include <sys/uio.h> |
9 | | #include <sys/socket.h> |
10 | | |
11 | | #include <linux/nfc.h> |
12 | | |
13 | | #include <errno.h> |
14 | | #include <libudev.h> |
15 | | #include <signal.h> |
16 | | #include <stdio.h> |
17 | | #include <string.h> |
18 | | #include <unistd.h> |
19 | | |
20 | | #include "fido.h" |
21 | | #include "fido/param.h" |
22 | | #include "netlink.h" |
23 | | #include "iso7816.h" |
24 | | |
25 | | struct nfc_linux { |
26 | | int fd; |
27 | | uint32_t dev; |
28 | | uint32_t target; |
29 | | sigset_t sigmask; |
30 | | const sigset_t *sigmaskp; |
31 | | struct fido_nl *nl; |
32 | | }; |
33 | | |
34 | | static char * |
35 | | get_parent_attr(struct udev_device *dev, const char *subsystem, |
36 | | const char *devtype, const char *attr) |
37 | 2.22M | { |
38 | 2.22M | struct udev_device *parent; |
39 | 2.22M | const char *value; |
40 | | |
41 | 2.22M | if ((parent = udev_device_get_parent_with_subsystem_devtype(dev, |
42 | 2.22M | subsystem, devtype)) == NULL || (value = |
43 | 2.22M | udev_device_get_sysattr_value(parent, attr)) == NULL) |
44 | 1.11M | return NULL; |
45 | | |
46 | 1.11M | return strdup(value); |
47 | 2.22M | } |
48 | | |
49 | | static char * |
50 | | get_usb_attr(struct udev_device *dev, const char *attr) |
51 | 2.22M | { |
52 | 2.22M | return get_parent_attr(dev, "usb", "usb_device", attr); |
53 | 2.22M | } |
54 | | |
55 | | static int |
56 | | copy_info(fido_dev_info_t *di, struct udev *udev, |
57 | | struct udev_list_entry *udev_entry) |
58 | 561k | { |
59 | 561k | const char *name; |
60 | 561k | char *str; |
61 | 561k | struct udev_device *dev = NULL; |
62 | 561k | void *ctx = NULL; |
63 | 561k | uint64_t id; |
64 | 561k | int ok = -1; |
65 | | |
66 | 561k | memset(di, 0, sizeof(*di)); |
67 | | |
68 | 561k | if ((name = udev_list_entry_get_name(udev_entry)) == NULL || |
69 | 561k | (dev = udev_device_new_from_syspath(udev, name)) == NULL) |
70 | 2.83k | goto fail; |
71 | 558k | if (asprintf(&di->path, "%s/%s", FIDO_NFC_PREFIX, name) == -1) { |
72 | 1.41k | di->path = NULL; |
73 | 1.41k | goto fail; |
74 | 1.41k | } |
75 | 557k | if ((di->manufacturer = get_usb_attr(dev, "manufacturer")) == NULL) |
76 | 4.15k | di->manufacturer = strdup(""); |
77 | 557k | if ((di->product = get_usb_attr(dev, "product")) == NULL) |
78 | 2.73k | di->product = strdup(""); |
79 | 557k | if (di->manufacturer == NULL || di->product == NULL) |
80 | 30 | goto fail; |
81 | | /* XXX assumes USB for vendor/product info */ |
82 | 557k | if ((str = get_usb_attr(dev, "idVendor")) != NULL && |
83 | 557k | fido_to_uint64(str, 16, &id) == 0 && id <= UINT16_MAX) |
84 | 0 | di->vendor_id = (int16_t)id; |
85 | 557k | free(str); |
86 | 557k | if ((str = get_usb_attr(dev, "idProduct")) != NULL && |
87 | 557k | fido_to_uint64(str, 16, &id) == 0 && id <= UINT16_MAX) |
88 | 0 | di->product_id = (int16_t)id; |
89 | 557k | free(str); |
90 | | |
91 | 557k | if ((ctx = fido_nfc_open(di->path)) == NULL) { |
92 | 557k | fido_log_debug("%s: fido_nfc_open", __func__); |
93 | 557k | goto fail; |
94 | 557k | } |
95 | | |
96 | 0 | ok = 0; |
97 | 561k | fail: |
98 | 561k | if (dev != NULL) |
99 | 558k | udev_device_unref(dev); |
100 | 561k | if (ctx != NULL) |
101 | 0 | fido_nfc_close(ctx); |
102 | | |
103 | 561k | if (ok < 0) { |
104 | 561k | free(di->path); |
105 | 561k | free(di->manufacturer); |
106 | 561k | free(di->product); |
107 | 561k | explicit_bzero(di, sizeof(*di)); |
108 | 561k | } |
109 | | |
110 | 561k | return ok; |
111 | 0 | } |
112 | | |
113 | | static int |
114 | | sysnum_from_syspath(const char *path) |
115 | 557k | { |
116 | 557k | struct udev *udev = NULL; |
117 | 557k | struct udev_device *dev = NULL; |
118 | 557k | const char *str; |
119 | 557k | uint64_t idx64; |
120 | 557k | int idx = -1; |
121 | | |
122 | 557k | if ((udev = udev_new()) != NULL && |
123 | 557k | (dev = udev_device_new_from_syspath(udev, path)) != NULL && |
124 | 557k | (str = udev_device_get_sysnum(dev)) != NULL && |
125 | 557k | fido_to_uint64(str, 10, &idx64) == 0 && idx64 < INT_MAX) |
126 | 553k | idx = (int)idx64; |
127 | | |
128 | 557k | if (dev != NULL) |
129 | 554k | udev_device_unref(dev); |
130 | 557k | if (udev != NULL) |
131 | 555k | udev_unref(udev); |
132 | | |
133 | 557k | return idx; |
134 | 557k | } |
135 | | |
136 | | int |
137 | | fido_nfc_manifest(fido_dev_info_t *devlist, size_t ilen, size_t *olen) |
138 | 1.18k | { |
139 | 1.18k | struct udev *udev = NULL; |
140 | 1.18k | struct udev_enumerate *udev_enum = NULL; |
141 | 1.18k | struct udev_list_entry *udev_list; |
142 | 1.18k | struct udev_list_entry *udev_entry; |
143 | 1.18k | int r = FIDO_ERR_INTERNAL; |
144 | | |
145 | 1.18k | *olen = 0; |
146 | | |
147 | 1.18k | if (ilen == 0) |
148 | 0 | return FIDO_OK; |
149 | | |
150 | 1.18k | if (devlist == NULL) |
151 | 0 | return FIDO_ERR_INVALID_ARGUMENT; |
152 | | |
153 | 1.18k | if ((udev = udev_new()) == NULL || |
154 | 1.18k | (udev_enum = udev_enumerate_new(udev)) == NULL) |
155 | 9 | goto fail; |
156 | | |
157 | 1.17k | if (udev_enumerate_add_match_subsystem(udev_enum, "nfc") < 0 || |
158 | 1.17k | udev_enumerate_scan_devices(udev_enum) < 0) |
159 | 6 | goto fail; |
160 | | |
161 | 1.17k | if ((udev_list = udev_enumerate_get_list_entry(udev_enum)) == NULL) { |
162 | 7 | r = FIDO_OK; /* zero nfc devices */ |
163 | 7 | goto fail; |
164 | 7 | } |
165 | | |
166 | 561k | udev_list_entry_foreach(udev_entry, udev_list) { |
167 | 561k | if (copy_info(&devlist[*olen], udev, udev_entry) == 0) { |
168 | 0 | devlist[*olen].io = (fido_dev_io_t) { |
169 | 0 | fido_nfc_open, |
170 | 0 | fido_nfc_close, |
171 | 0 | fido_nfc_read, |
172 | 0 | fido_nfc_write, |
173 | 0 | }; |
174 | 0 | devlist[*olen].transport = (fido_dev_transport_t) { |
175 | 0 | fido_nfc_rx, |
176 | 0 | fido_nfc_tx, |
177 | 0 | }; |
178 | 0 | if (++(*olen) == ilen) |
179 | 0 | break; |
180 | 0 | } |
181 | 561k | } |
182 | | |
183 | 1.16k | r = FIDO_OK; |
184 | 1.18k | fail: |
185 | 1.18k | if (udev_enum != NULL) |
186 | 1.17k | udev_enumerate_unref(udev_enum); |
187 | 1.18k | if (udev != NULL) |
188 | 1.18k | udev_unref(udev); |
189 | | |
190 | 1.18k | return r; |
191 | 1.16k | } |
192 | | |
193 | | static int |
194 | | nfc_target_connect(struct nfc_linux *ctx) |
195 | 0 | { |
196 | 0 | struct sockaddr_nfc sa; |
197 | |
|
198 | 0 | memset(&sa, 0, sizeof(sa)); |
199 | 0 | sa.sa_family = AF_NFC; |
200 | 0 | sa.dev_idx = ctx->dev; |
201 | 0 | sa.target_idx = ctx->target; |
202 | 0 | sa.nfc_protocol = NFC_PROTO_ISO14443; |
203 | |
|
204 | 0 | if ((ctx->fd = socket(AF_NFC, SOCK_SEQPACKET | SOCK_CLOEXEC, |
205 | 0 | NFC_SOCKPROTO_RAW)) == -1) { |
206 | 0 | fido_log_error(errno, "%s: socket", __func__); |
207 | 0 | return -1; |
208 | 0 | } |
209 | 0 | if (connect(ctx->fd, (struct sockaddr *)&sa, sizeof(sa)) == -1) { |
210 | 0 | fido_log_error(errno, "%s: connect", __func__); |
211 | 0 | if (close(ctx->fd) == -1) |
212 | 0 | fido_log_error(errno, "%s: close", __func__); |
213 | 0 | ctx->fd = -1; |
214 | 0 | return -1; |
215 | 0 | } |
216 | | |
217 | 0 | return 0; |
218 | 0 | } |
219 | | |
220 | | static void |
221 | | nfc_free(struct nfc_linux **ctx_p) |
222 | 1.11M | { |
223 | 1.11M | struct nfc_linux *ctx; |
224 | | |
225 | 1.11M | if (ctx_p == NULL || (ctx = *ctx_p) == NULL) |
226 | 558k | return; |
227 | 551k | if (ctx->fd != -1 && close(ctx->fd) == -1) |
228 | 551k | fido_log_error(errno, "%s: close", __func__); |
229 | 551k | if (ctx->nl != NULL) |
230 | 264 | fido_nl_free(&ctx->nl); |
231 | | |
232 | 551k | free(ctx); |
233 | 551k | *ctx_p = NULL; |
234 | 551k | } |
235 | | |
236 | | static struct nfc_linux * |
237 | | nfc_new(uint32_t dev) |
238 | 553k | { |
239 | 553k | struct nfc_linux *ctx; |
240 | | |
241 | 553k | if ((ctx = calloc(1, sizeof(*ctx))) == NULL || |
242 | 553k | (ctx->nl = fido_nl_new()) == NULL) { |
243 | 552k | nfc_free(&ctx); |
244 | 552k | return NULL; |
245 | 552k | } |
246 | | |
247 | 264 | ctx->fd = -1; |
248 | 264 | ctx->dev = dev; |
249 | | |
250 | 264 | return ctx; |
251 | 553k | } |
252 | | |
253 | | void * |
254 | | fido_nfc_open(const char *path) |
255 | 557k | { |
256 | 557k | struct nfc_linux *ctx = NULL; |
257 | 557k | int idx; |
258 | | |
259 | 557k | if (strncmp(path, FIDO_NFC_PREFIX, strlen(FIDO_NFC_PREFIX)) != 0) { |
260 | 0 | fido_log_debug("%s: bad prefix", __func__); |
261 | 0 | goto fail; |
262 | 0 | } |
263 | 557k | if ((idx = sysnum_from_syspath(path + strlen(FIDO_NFC_PREFIX))) < 0 || |
264 | 557k | (ctx = nfc_new((uint32_t)idx)) == NULL) { |
265 | 557k | fido_log_debug("%s: nfc_new", __func__); |
266 | 557k | goto fail; |
267 | 557k | } |
268 | 264 | if (fido_nl_power_nfc(ctx->nl, ctx->dev) < 0 || |
269 | 264 | fido_nl_get_nfc_target(ctx->nl, ctx->dev, &ctx->target) < 0 || |
270 | 264 | nfc_target_connect(ctx) < 0) { |
271 | 264 | fido_log_debug("%s: netlink", __func__); |
272 | 264 | goto fail; |
273 | 264 | } |
274 | | |
275 | 0 | return ctx; |
276 | 557k | fail: |
277 | 557k | nfc_free(&ctx); |
278 | 557k | return NULL; |
279 | 264 | } |
280 | | |
281 | | void |
282 | | fido_nfc_close(void *handle) |
283 | 0 | { |
284 | 0 | struct nfc_linux *ctx = handle; |
285 | |
|
286 | 0 | nfc_free(&ctx); |
287 | 0 | } |
288 | | |
289 | | int |
290 | | fido_nfc_set_sigmask(void *handle, const fido_sigset_t *sigmask) |
291 | 0 | { |
292 | 0 | struct nfc_linux *ctx = handle; |
293 | |
|
294 | 0 | ctx->sigmask = *sigmask; |
295 | 0 | ctx->sigmaskp = &ctx->sigmask; |
296 | |
|
297 | 0 | return FIDO_OK; |
298 | 0 | } |
299 | | |
300 | | int |
301 | | fido_nfc_read(void *handle, unsigned char *buf, size_t len, int ms) |
302 | 0 | { |
303 | 0 | struct nfc_linux *ctx = handle; |
304 | 0 | struct iovec iov[2]; |
305 | 0 | uint8_t preamble; |
306 | 0 | ssize_t r; |
307 | |
|
308 | 0 | memset(&iov, 0, sizeof(iov)); |
309 | 0 | iov[0].iov_base = &preamble; |
310 | 0 | iov[0].iov_len = sizeof(preamble); |
311 | 0 | iov[1].iov_base = buf; |
312 | 0 | iov[1].iov_len = len; |
313 | |
|
314 | 0 | if (fido_hid_unix_wait(ctx->fd, ms, ctx->sigmaskp) < 0) { |
315 | 0 | fido_log_debug("%s: fido_hid_unix_wait", __func__); |
316 | 0 | return -1; |
317 | 0 | } |
318 | 0 | if ((r = readv(ctx->fd, iov, nitems(iov))) == -1) { |
319 | 0 | fido_log_error(errno, "%s: read", __func__); |
320 | 0 | return -1; |
321 | 0 | } |
322 | 0 | if (r < 1) { |
323 | 0 | fido_log_debug("%s: %zd < 1", __func__, r); |
324 | 0 | return -1; |
325 | 0 | } |
326 | 0 | if (preamble != 0x00) { |
327 | 0 | fido_log_debug("%s: preamble", __func__); |
328 | 0 | return -1; |
329 | 0 | } |
330 | | |
331 | 0 | r--; |
332 | 0 | fido_log_xxd(buf, (size_t)r, "%s", __func__); |
333 | |
|
334 | 0 | return (int)r; |
335 | 0 | } |
336 | | |
337 | | int |
338 | | fido_nfc_write(void *handle, const unsigned char *buf, size_t len) |
339 | 0 | { |
340 | 0 | struct nfc_linux *ctx = handle; |
341 | 0 | ssize_t r; |
342 | |
|
343 | 0 | fido_log_xxd(buf, len, "%s", __func__); |
344 | |
|
345 | 0 | if (len > INT_MAX) { |
346 | 0 | fido_log_debug("%s: len", __func__); |
347 | 0 | return -1; |
348 | 0 | } |
349 | 0 | if ((r = write(ctx->fd, buf, len)) == -1) { |
350 | 0 | fido_log_error(errno, "%s: write", __func__); |
351 | 0 | return -1; |
352 | 0 | } |
353 | 0 | if (r < 0 || (size_t)r != len) { |
354 | 0 | fido_log_debug("%s: %zd != %zu", __func__, r, len); |
355 | 0 | return -1; |
356 | 0 | } |
357 | | |
358 | 0 | return (int)r; |
359 | 0 | } |