xref: /freebsd/contrib/libfido2/src/hid.c (revision 2ccfa855b2fc331819953e3de1b1c15ce5b95a7e)
1 /*
2  * Copyright (c) 2018 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 "fido.h"
9 
10 static int
get_key_len(uint8_t tag,uint8_t * key,size_t * key_len)11 get_key_len(uint8_t tag, uint8_t *key, size_t *key_len)
12 {
13 	*key = tag & 0xfc;
14 	if ((*key & 0xf0) == 0xf0) {
15 		fido_log_debug("%s: *key=0x%02x", __func__, *key);
16 		return (-1);
17 	}
18 
19 	*key_len = tag & 0x3;
20 	if (*key_len == 3) {
21 		*key_len = 4;
22 	}
23 
24 	return (0);
25 }
26 
27 static int
get_key_val(const void * body,size_t key_len,uint32_t * val)28 get_key_val(const void *body, size_t key_len, uint32_t *val)
29 {
30 	const uint8_t *ptr = body;
31 
32 	switch (key_len) {
33 	case 0:
34 		*val = 0;
35 		break;
36 	case 1:
37 		*val = ptr[0];
38 		break;
39 	case 2:
40 		*val = (uint32_t)((ptr[1] << 8) | ptr[0]);
41 		break;
42 	default:
43 		fido_log_debug("%s: key_len=%zu", __func__, key_len);
44 		return (-1);
45 	}
46 
47 	return (0);
48 }
49 
50 int
fido_hid_get_usage(const uint8_t * report_ptr,size_t report_len,uint32_t * usage_page)51 fido_hid_get_usage(const uint8_t *report_ptr, size_t report_len,
52     uint32_t *usage_page)
53 {
54 	const uint8_t	*ptr = report_ptr;
55 	size_t		 len = report_len;
56 
57 	while (len > 0) {
58 		const uint8_t tag = ptr[0];
59 		ptr++;
60 		len--;
61 
62 		uint8_t  key;
63 		size_t   key_len;
64 		uint32_t key_val;
65 
66 		if (get_key_len(tag, &key, &key_len) < 0 || key_len > len ||
67 		    get_key_val(ptr, key_len, &key_val) < 0) {
68 			return (-1);
69 		}
70 
71 		if (key == 0x4) {
72 			*usage_page = key_val;
73 		}
74 
75 		ptr += key_len;
76 		len -= key_len;
77 	}
78 
79 	return (0);
80 }
81 
82 int
fido_hid_get_report_len(const uint8_t * report_ptr,size_t report_len,size_t * report_in_len,size_t * report_out_len)83 fido_hid_get_report_len(const uint8_t *report_ptr, size_t report_len,
84     size_t *report_in_len, size_t *report_out_len)
85 {
86 	const uint8_t	*ptr = report_ptr;
87 	size_t		 len = report_len;
88 	uint32_t	 report_size = 0;
89 
90 	while (len > 0) {
91 		const uint8_t tag = ptr[0];
92 		ptr++;
93 		len--;
94 
95 		uint8_t  key;
96 		size_t   key_len;
97 		uint32_t key_val;
98 
99 		if (get_key_len(tag, &key, &key_len) < 0 || key_len > len ||
100 		    get_key_val(ptr, key_len, &key_val) < 0) {
101 			return (-1);
102 		}
103 
104 		if (key == 0x94) {
105 			report_size = key_val;
106 		} else if (key == 0x80) {
107 			*report_in_len = (size_t)report_size;
108 		} else if (key == 0x90) {
109 			*report_out_len = (size_t)report_size;
110 		}
111 
112 		ptr += key_len;
113 		len -= key_len;
114 	}
115 
116 	return (0);
117 }
118 
119 fido_dev_info_t *
fido_dev_info_new(size_t n)120 fido_dev_info_new(size_t n)
121 {
122 	return (calloc(n, sizeof(fido_dev_info_t)));
123 }
124 
125 static void
fido_dev_info_reset(fido_dev_info_t * di)126 fido_dev_info_reset(fido_dev_info_t *di)
127 {
128 	free(di->path);
129 	free(di->manufacturer);
130 	free(di->product);
131 	memset(di, 0, sizeof(*di));
132 }
133 
134 void
fido_dev_info_free(fido_dev_info_t ** devlist_p,size_t n)135 fido_dev_info_free(fido_dev_info_t **devlist_p, size_t n)
136 {
137 	fido_dev_info_t *devlist;
138 
139 	if (devlist_p == NULL || (devlist = *devlist_p) == NULL)
140 		return;
141 
142 	for (size_t i = 0; i < n; i++)
143 		fido_dev_info_reset(&devlist[i]);
144 
145 	free(devlist);
146 
147 	*devlist_p = NULL;
148 }
149 
150 const fido_dev_info_t *
fido_dev_info_ptr(const fido_dev_info_t * devlist,size_t i)151 fido_dev_info_ptr(const fido_dev_info_t *devlist, size_t i)
152 {
153 	return (&devlist[i]);
154 }
155 
156 int
fido_dev_info_set(fido_dev_info_t * devlist,size_t i,const char * path,const char * manufacturer,const char * product,const fido_dev_io_t * io,const fido_dev_transport_t * transport)157 fido_dev_info_set(fido_dev_info_t *devlist, size_t i,
158     const char *path, const char *manufacturer, const char *product,
159     const fido_dev_io_t *io, const fido_dev_transport_t *transport)
160 {
161 	char *path_copy = NULL, *manu_copy = NULL, *prod_copy = NULL;
162 	int r;
163 
164 	if (path == NULL || manufacturer == NULL || product == NULL ||
165 	    io == NULL) {
166 		r = FIDO_ERR_INVALID_ARGUMENT;
167 		goto out;
168 	}
169 
170 	if ((path_copy = strdup(path)) == NULL ||
171 	    (manu_copy = strdup(manufacturer)) == NULL ||
172 	    (prod_copy = strdup(product)) == NULL) {
173 		r = FIDO_ERR_INTERNAL;
174 		goto out;
175 	}
176 
177 	fido_dev_info_reset(&devlist[i]);
178 	devlist[i].path = path_copy;
179 	devlist[i].manufacturer = manu_copy;
180 	devlist[i].product = prod_copy;
181 	devlist[i].io = *io;
182 	if (transport)
183 		devlist[i].transport = *transport;
184 	r = FIDO_OK;
185 out:
186 	if (r != FIDO_OK) {
187 		free(prod_copy);
188 		free(manu_copy);
189 		free(path_copy);
190 	}
191 	return (r);
192 }
193 
194 const char *
fido_dev_info_path(const fido_dev_info_t * di)195 fido_dev_info_path(const fido_dev_info_t *di)
196 {
197 	return (di->path);
198 }
199 
200 int16_t
fido_dev_info_vendor(const fido_dev_info_t * di)201 fido_dev_info_vendor(const fido_dev_info_t *di)
202 {
203 	return (di->vendor_id);
204 }
205 
206 int16_t
fido_dev_info_product(const fido_dev_info_t * di)207 fido_dev_info_product(const fido_dev_info_t *di)
208 {
209 	return (di->product_id);
210 }
211 
212 const char *
fido_dev_info_manufacturer_string(const fido_dev_info_t * di)213 fido_dev_info_manufacturer_string(const fido_dev_info_t *di)
214 {
215 	return (di->manufacturer);
216 }
217 
218 const char *
fido_dev_info_product_string(const fido_dev_info_t * di)219 fido_dev_info_product_string(const fido_dev_info_t *di)
220 {
221 	return (di->product);
222 }
223