libnfc 1.8.0
nfc-internal.c
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1/*-
2 * Free/Libre Near Field Communication (NFC) library
3 *
4 * Libnfc historical contributors:
5 * Copyright (C) 2009 Roel Verdult
6 * Copyright (C) 2009-2013 Romuald Conty
7 * Copyright (C) 2010-2012 Romain Tartière
8 * Copyright (C) 2010-2013 Philippe Teuwen
9 * Copyright (C) 2012-2013 Ludovic Rousseau
10 * See AUTHORS file for a more comprehensive list of contributors.
11 * Additional contributors of this file:
12 * Copyright (C) 2020 Adam Laurie
13 *
14 * This program is free software: you can redistribute it and/or modify it
15 * under the terms of the GNU Lesser General Public License as published by the
16 * Free Software Foundation, either version 3 of the License, or (at your
17 * option) any later version.
18 *
19 * This program is distributed in the hope that it will be useful, but WITHOUT
20 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
21 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
22 * more details.
23 *
24 * You should have received a copy of the GNU Lesser General Public License
25 * along with this program. If not, see <http://www.gnu.org/licenses/>
26 */
27
33#include <nfc/nfc.h>
34#include "nfc-internal.h"
35
36#ifdef HAVE_CONFIG_H
37#include "config.h"
38#endif
39
40#ifdef CONFFILES
41#include "conf.h"
42#endif
43
44#include <stdlib.h>
45#include <string.h>
46#include <inttypes.h>
47
48#define LOG_GROUP NFC_LOG_GROUP_GENERAL
49#define LOG_CATEGORY "libnfc.general"
50
51void
52string_as_boolean(const char *s, bool *value)
53{
54 if (s) {
55 if (!(*value)) {
56 if ((strcmp(s, "yes") == 0) ||
57 (strcmp(s, "true") == 0) ||
58 (strcmp(s, "1") == 0)) {
59 *value = true;
60 return;
61 }
62 } else {
63 if ((strcmp(s, "no") == 0) ||
64 (strcmp(s, "false") == 0) ||
65 (strcmp(s, "0") == 0)) {
66 *value = false;
67 return;
68 }
69 }
70 }
71}
72
74nfc_context_new(void)
75{
76 nfc_context *res = malloc(sizeof(*res));
77
78 if (!res) {
79 return NULL;
80 }
81
82 // Set default context values
83 res->allow_autoscan = true;
84 res->allow_intrusive_scan = false;
85#ifdef DEBUG
86 res->log_level = 3;
87#else
88 res->log_level = 1;
89#endif
90
91 // Clear user defined devices array
92 for (int i = 0; i < MAX_USER_DEFINED_DEVICES; i++) {
93 strcpy(res->user_defined_devices[i].name, "");
94 strcpy(res->user_defined_devices[i].connstring, "");
95 res->user_defined_devices[i].optional = false;
96 }
97 res->user_defined_device_count = 0;
98
99#ifdef ENVVARS
100 // Load user defined device from environment variable at first
101 char *envvar = getenv("LIBNFC_DEFAULT_DEVICE");
102 if (envvar) {
103 strcpy(res->user_defined_devices[0].name, "user defined default device");
104 strncpy(res->user_defined_devices[0].connstring, envvar, NFC_BUFSIZE_CONNSTRING);
105 res->user_defined_devices[0].connstring[NFC_BUFSIZE_CONNSTRING - 1] = '\0';
106 res->user_defined_device_count++;
107 }
108
109#endif // ENVVARS
110
111#ifdef CONFFILES
112 // Load options from configuration file (ie. /etc/nfc/libnfc.conf)
113 conf_load(res);
114#endif // CONFFILES
115
116#ifdef ENVVARS
117 // Environment variables
118
119 // Load user defined device from environment variable as the only reader
120 envvar = getenv("LIBNFC_DEVICE");
121 if (envvar) {
122 strcpy(res->user_defined_devices[0].name, "user defined device");
123 strncpy(res->user_defined_devices[0].connstring, envvar, NFC_BUFSIZE_CONNSTRING);
124 res->user_defined_devices[0].connstring[NFC_BUFSIZE_CONNSTRING - 1] = '\0';
125 res->user_defined_device_count = 1;
126 }
127
128 // Load "auto scan" option
129 envvar = getenv("LIBNFC_AUTO_SCAN");
130 string_as_boolean(envvar, &(res->allow_autoscan));
131
132 // Load "intrusive scan" option
133 envvar = getenv("LIBNFC_INTRUSIVE_SCAN");
134 string_as_boolean(envvar, &(res->allow_intrusive_scan));
135
136 // log level
137 envvar = getenv("LIBNFC_LOG_LEVEL");
138 if (envvar) {
139 res->log_level = atoi(envvar);
140 }
141#endif // ENVVARS
142
143 // Initialize log before use it...
144 log_init(res);
145
146 // Debug context state
147#if defined DEBUG
148 log_put(LOG_GROUP, LOG_CATEGORY, NFC_LOG_PRIORITY_NONE, "log_level is set to %"PRIu32, res->log_level);
149#else
150 log_put(LOG_GROUP, LOG_CATEGORY, NFC_LOG_PRIORITY_DEBUG, "log_level is set to %"PRIu32, res->log_level);
151#endif
152 log_put(LOG_GROUP, LOG_CATEGORY, NFC_LOG_PRIORITY_DEBUG, "allow_autoscan is set to %s", (res->allow_autoscan) ? "true" : "false");
153 log_put(LOG_GROUP, LOG_CATEGORY, NFC_LOG_PRIORITY_DEBUG, "allow_intrusive_scan is set to %s", (res->allow_intrusive_scan) ? "true" : "false");
154
155 log_put(LOG_GROUP, LOG_CATEGORY, NFC_LOG_PRIORITY_DEBUG, "%d device(s) defined by user", res->user_defined_device_count);
156 for (uint32_t i = 0; i < res->user_defined_device_count; i++) {
157 log_put(LOG_GROUP, LOG_CATEGORY, NFC_LOG_PRIORITY_DEBUG, " #%d name: \"%s\", connstring: \"%s\"", i, res->user_defined_devices[i].name, res->user_defined_devices[i].connstring);
158 }
159 return res;
160}
161
162void
163nfc_context_free(nfc_context *context)
164{
165 log_exit();
166 free(context);
167}
168
169void
170prepare_initiator_data(const nfc_modulation nm, uint8_t **ppbtInitiatorData, size_t *pszInitiatorData)
171{
172 switch (nm.nmt) {
173 case NMT_ISO14443B:
174 // Application Family Identifier (AFI) must equals 0x00 in order to wakeup all ISO14443-B PICCs (see ISO/IEC 14443-3)
175 *ppbtInitiatorData = (uint8_t *) "\x00";
176 *pszInitiatorData = 1;
177 break;
178 case NMT_ISO14443BI:
179 // APGEN
180 *ppbtInitiatorData = (uint8_t *) "\x01\x0b\x3f\x80";
181 *pszInitiatorData = 4;
182 break;
183 case NMT_FELICA:
184 // polling payload must be present (see ISO/IEC 18092 11.2.2.5)
185 *ppbtInitiatorData = (uint8_t *) "\x00\xff\xff\x01\x00";
186 *pszInitiatorData = 5;
187 break;
188 case NMT_ISO14443A:
189 case NMT_ISO14443B2CT:
190 case NMT_ISO14443B2SR:
191 case NMT_ISO14443BICLASS:
192 case NMT_JEWEL:
193 case NMT_BARCODE:
194 case NMT_DEP:
195 *ppbtInitiatorData = NULL;
196 *pszInitiatorData = 0;
197 break;
198 }
199}
200
201int
202connstring_decode(const nfc_connstring connstring, const char *driver_name, const char *bus_name, char **pparam1, char **pparam2)
203{
204 if (driver_name == NULL) {
205 driver_name = "";
206 }
207 if (bus_name == NULL) {
208 bus_name = "";
209 }
210 int n = strlen(connstring) + 1;
211 char *param0 = malloc(n);
212 if (param0 == NULL) {
213 perror("malloc");
214 return 0;
215 }
216 char *param1 = malloc(n);
217 if (param1 == NULL) {
218 perror("malloc");
219 free(param0);
220 return 0;
221 }
222 char *param2 = malloc(n);
223 if (param2 == NULL) {
224 perror("malloc");
225 free(param0);
226 free(param1);
227 return 0;
228 }
229
230 char format[32];
231 snprintf(format, sizeof(format), "%%%i[^:]:%%%i[^:]:%%%i[^:]", n - 1, n - 1, n - 1);
232 int res = sscanf(connstring, format, param0, param1, param2);
233
234 if (res < 1 || ((0 != strcmp(param0, driver_name)) &&
235 (0 != strcmp(param0, bus_name)))) {
236 // Driver name does not match.
237 res = 0;
238 }
239 if (pparam1 != NULL) {
240 if (res < 2) {
241 free(param1);
242 *pparam1 = NULL;
243 } else {
244 *pparam1 = param1;
245 }
246 } else {
247 free(param1);
248 }
249 if (pparam2 != NULL) {
250 if (res < 3) {
251 free(param2);
252 *pparam2 = NULL;
253 } else {
254 *pparam2 = param2;
255 }
256 } else {
257 free(param2);
258 }
259 free(param0);
260 return res;
261}
262
Internal defines and macros.
char nfc_connstring[NFC_BUFSIZE_CONNSTRING]
Definition: nfc-types.h:63
libnfc interface
NFC library context Struct which contains internal options, references, pointers, etc....
Definition: nfc-internal.h:175
NFC modulation structure.
Definition: nfc-types.h:342