Loading...
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * apple-properties.c - EFI device properties on Macs
4 * Copyright (C) 2016 Lukas Wunner <lukas@wunner.de>
5 *
6 * Note, all properties are considered as u8 arrays.
7 * To get a value of any of them the caller must use device_property_read_u8_array().
8 */
9
10#define pr_fmt(fmt) "apple-properties: " fmt
11
12#include <linux/memblock.h>
13#include <linux/efi.h>
14#include <linux/io.h>
15#include <linux/platform_data/x86/apple.h>
16#include <linux/property.h>
17#include <linux/slab.h>
18#include <linux/ucs2_string.h>
19#include <asm/setup.h>
20
21static bool dump_properties __initdata;
22
23static int __init dump_properties_enable(char *arg)
24{
25 dump_properties = true;
26 return 0;
27}
28
29__setup("dump_apple_properties", dump_properties_enable);
30
31struct dev_header {
32 u32 len;
33 u32 prop_count;
34 struct efi_dev_path path[];
35 /*
36 * followed by key/value pairs, each key and value preceded by u32 len,
37 * len includes itself, value may be empty (in which case its len is 4)
38 */
39};
40
41struct properties_header {
42 u32 len;
43 u32 version;
44 u32 dev_count;
45 struct dev_header dev_header[];
46};
47
48static void __init unmarshal_key_value_pairs(struct dev_header *dev_header,
49 struct device *dev, const void *ptr,
50 struct property_entry entry[])
51{
52 int i;
53
54 for (i = 0; i < dev_header->prop_count; i++) {
55 int remaining = dev_header->len - (ptr - (void *)dev_header);
56 u32 key_len, val_len, entry_len;
57 const u8 *entry_data;
58 char *key;
59
60 if (sizeof(key_len) > remaining)
61 break;
62
63 key_len = *(typeof(key_len) *)ptr;
64 if (key_len + sizeof(val_len) > remaining ||
65 key_len < sizeof(key_len) + sizeof(efi_char16_t) ||
66 *(efi_char16_t *)(ptr + sizeof(key_len)) == 0) {
67 dev_err(dev, "invalid property name len at %#zx\n",
68 ptr - (void *)dev_header);
69 break;
70 }
71
72 val_len = *(typeof(val_len) *)(ptr + key_len);
73 if (key_len + val_len > remaining ||
74 val_len < sizeof(val_len)) {
75 dev_err(dev, "invalid property val len at %#zx\n",
76 ptr - (void *)dev_header + key_len);
77 break;
78 }
79
80 /* 4 bytes to accommodate UTF-8 code points + null byte */
81 key = kzalloc((key_len - sizeof(key_len)) * 4 + 1, GFP_KERNEL);
82 if (!key) {
83 dev_err(dev, "cannot allocate property name\n");
84 break;
85 }
86 ucs2_as_utf8(key, ptr + sizeof(key_len),
87 key_len - sizeof(key_len));
88
89 entry_data = ptr + key_len + sizeof(val_len);
90 entry_len = val_len - sizeof(val_len);
91 entry[i] = PROPERTY_ENTRY_U8_ARRAY_LEN(key, entry_data,
92 entry_len);
93 if (dump_properties) {
94 dev_info(dev, "property: %s\n", key);
95 print_hex_dump(KERN_INFO, pr_fmt(), DUMP_PREFIX_OFFSET,
96 16, 1, entry_data, entry_len, true);
97 }
98
99 ptr += key_len + val_len;
100 }
101
102 if (i != dev_header->prop_count) {
103 dev_err(dev, "got %d device properties, expected %u\n", i,
104 dev_header->prop_count);
105 print_hex_dump(KERN_ERR, pr_fmt(), DUMP_PREFIX_OFFSET,
106 16, 1, dev_header, dev_header->len, true);
107 return;
108 }
109
110 dev_info(dev, "assigning %d device properties\n", i);
111}
112
113static int __init unmarshal_devices(struct properties_header *properties)
114{
115 size_t offset = offsetof(struct properties_header, dev_header[0]);
116
117 while (offset + sizeof(struct dev_header) < properties->len) {
118 struct dev_header *dev_header = (void *)properties + offset;
119 struct property_entry *entry = NULL;
120 const struct efi_dev_path *ptr;
121 struct device *dev;
122 size_t len;
123 int ret, i;
124
125 if (offset + dev_header->len > properties->len ||
126 dev_header->len <= sizeof(*dev_header)) {
127 pr_err("invalid len in dev_header at %#zx\n", offset);
128 return -EINVAL;
129 }
130
131 ptr = dev_header->path;
132 len = dev_header->len - sizeof(*dev_header);
133
134 dev = efi_get_device_by_path(&ptr, &len);
135 if (IS_ERR(dev)) {
136 pr_err("device path parse error %ld at %#zx:\n",
137 PTR_ERR(dev), (void *)ptr - (void *)dev_header);
138 print_hex_dump(KERN_ERR, pr_fmt(), DUMP_PREFIX_OFFSET,
139 16, 1, dev_header, dev_header->len, true);
140 dev = NULL;
141 goto skip_device;
142 }
143
144 entry = kcalloc(dev_header->prop_count + 1, sizeof(*entry),
145 GFP_KERNEL);
146 if (!entry) {
147 dev_err(dev, "cannot allocate properties\n");
148 goto skip_device;
149 }
150
151 unmarshal_key_value_pairs(dev_header, dev, ptr, entry);
152 if (!entry[0].name)
153 goto skip_device;
154
155 ret = device_add_properties(dev, entry); /* makes deep copy */
156 if (ret)
157 dev_err(dev, "error %d assigning properties\n", ret);
158
159 for (i = 0; entry[i].name; i++)
160 kfree(entry[i].name);
161
162skip_device:
163 kfree(entry);
164 put_device(dev);
165 offset += dev_header->len;
166 }
167
168 return 0;
169}
170
171static int __init map_properties(void)
172{
173 struct properties_header *properties;
174 struct setup_data *data;
175 u32 data_len;
176 u64 pa_data;
177 int ret;
178
179 if (!x86_apple_machine)
180 return 0;
181
182 pa_data = boot_params.hdr.setup_data;
183 while (pa_data) {
184 data = memremap(pa_data, sizeof(*data), MEMREMAP_WB);
185 if (!data) {
186 pr_err("cannot map setup_data header\n");
187 return -ENOMEM;
188 }
189
190 if (data->type != SETUP_APPLE_PROPERTIES) {
191 pa_data = data->next;
192 memunmap(data);
193 continue;
194 }
195
196 data_len = data->len;
197 memunmap(data);
198
199 data = memremap(pa_data, sizeof(*data) + data_len, MEMREMAP_WB);
200 if (!data) {
201 pr_err("cannot map setup_data payload\n");
202 return -ENOMEM;
203 }
204
205 properties = (struct properties_header *)data->data;
206 if (properties->version != 1) {
207 pr_err("unsupported version:\n");
208 print_hex_dump(KERN_ERR, pr_fmt(), DUMP_PREFIX_OFFSET,
209 16, 1, properties, data_len, true);
210 ret = -ENOTSUPP;
211 } else if (properties->len != data_len) {
212 pr_err("length mismatch, expected %u\n", data_len);
213 print_hex_dump(KERN_ERR, pr_fmt(), DUMP_PREFIX_OFFSET,
214 16, 1, properties, data_len, true);
215 ret = -EINVAL;
216 } else
217 ret = unmarshal_devices(properties);
218
219 /*
220 * Can only free the setup_data payload but not its header
221 * to avoid breaking the chain of ->next pointers.
222 */
223 data->len = 0;
224 memunmap(data);
225 memblock_free_late(pa_data + sizeof(*data), data_len);
226
227 return ret;
228 }
229 return 0;
230}
231
232fs_initcall(map_properties);
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * apple-properties.c - EFI device properties on Macs
4 * Copyright (C) 2016 Lukas Wunner <lukas@wunner.de>
5 *
6 * Properties are stored either as:
7 * u8 arrays which can be retrieved with device_property_read_u8_array() or
8 * booleans which can be queried with device_property_present().
9 */
10
11#define pr_fmt(fmt) "apple-properties: " fmt
12
13#include <linux/memblock.h>
14#include <linux/efi.h>
15#include <linux/io.h>
16#include <linux/platform_data/x86/apple.h>
17#include <linux/property.h>
18#include <linux/slab.h>
19#include <linux/ucs2_string.h>
20#include <asm/setup.h>
21
22static bool dump_properties __initdata;
23
24static int __init dump_properties_enable(char *arg)
25{
26 dump_properties = true;
27 return 0;
28}
29
30__setup("dump_apple_properties", dump_properties_enable);
31
32struct dev_header {
33 u32 len;
34 u32 prop_count;
35 struct efi_dev_path path[];
36 /*
37 * followed by key/value pairs, each key and value preceded by u32 len,
38 * len includes itself, value may be empty (in which case its len is 4)
39 */
40};
41
42struct properties_header {
43 u32 len;
44 u32 version;
45 u32 dev_count;
46 struct dev_header dev_header[];
47};
48
49static void __init unmarshal_key_value_pairs(struct dev_header *dev_header,
50 struct device *dev, const void *ptr,
51 struct property_entry entry[])
52{
53 int i;
54
55 for (i = 0; i < dev_header->prop_count; i++) {
56 int remaining = dev_header->len - (ptr - (void *)dev_header);
57 u32 key_len, val_len, entry_len;
58 const u8 *entry_data;
59 char *key;
60
61 if (sizeof(key_len) > remaining)
62 break;
63
64 key_len = *(typeof(key_len) *)ptr;
65 if (key_len + sizeof(val_len) > remaining ||
66 key_len < sizeof(key_len) + sizeof(efi_char16_t) ||
67 *(efi_char16_t *)(ptr + sizeof(key_len)) == 0) {
68 dev_err(dev, "invalid property name len at %#zx\n",
69 ptr - (void *)dev_header);
70 break;
71 }
72
73 val_len = *(typeof(val_len) *)(ptr + key_len);
74 if (key_len + val_len > remaining ||
75 val_len < sizeof(val_len)) {
76 dev_err(dev, "invalid property val len at %#zx\n",
77 ptr - (void *)dev_header + key_len);
78 break;
79 }
80
81 /* 4 bytes to accommodate UTF-8 code points + null byte */
82 key = kzalloc((key_len - sizeof(key_len)) * 4 + 1, GFP_KERNEL);
83 if (!key) {
84 dev_err(dev, "cannot allocate property name\n");
85 break;
86 }
87 ucs2_as_utf8(key, ptr + sizeof(key_len),
88 key_len - sizeof(key_len));
89
90 entry_data = ptr + key_len + sizeof(val_len);
91 entry_len = val_len - sizeof(val_len);
92 if (entry_len)
93 entry[i] = PROPERTY_ENTRY_U8_ARRAY_LEN(key, entry_data,
94 entry_len);
95 else
96 entry[i] = PROPERTY_ENTRY_BOOL(key);
97
98 if (dump_properties) {
99 dev_info(dev, "property: %s\n", key);
100 print_hex_dump(KERN_INFO, pr_fmt(), DUMP_PREFIX_OFFSET,
101 16, 1, entry_data, entry_len, true);
102 }
103
104 ptr += key_len + val_len;
105 }
106
107 if (i != dev_header->prop_count) {
108 dev_err(dev, "got %d device properties, expected %u\n", i,
109 dev_header->prop_count);
110 print_hex_dump(KERN_ERR, pr_fmt(), DUMP_PREFIX_OFFSET,
111 16, 1, dev_header, dev_header->len, true);
112 return;
113 }
114
115 dev_info(dev, "assigning %d device properties\n", i);
116}
117
118static int __init unmarshal_devices(struct properties_header *properties)
119{
120 size_t offset = offsetof(struct properties_header, dev_header[0]);
121
122 while (offset + sizeof(struct dev_header) < properties->len) {
123 struct dev_header *dev_header = (void *)properties + offset;
124 struct property_entry *entry = NULL;
125 const struct efi_dev_path *ptr;
126 struct device *dev;
127 size_t len;
128 int ret, i;
129
130 if (offset + dev_header->len > properties->len ||
131 dev_header->len <= sizeof(*dev_header)) {
132 pr_err("invalid len in dev_header at %#zx\n", offset);
133 return -EINVAL;
134 }
135
136 ptr = dev_header->path;
137 len = dev_header->len - sizeof(*dev_header);
138
139 dev = efi_get_device_by_path(&ptr, &len);
140 if (IS_ERR(dev)) {
141 pr_err("device path parse error %ld at %#zx:\n",
142 PTR_ERR(dev), (void *)ptr - (void *)dev_header);
143 print_hex_dump(KERN_ERR, pr_fmt(), DUMP_PREFIX_OFFSET,
144 16, 1, dev_header, dev_header->len, true);
145 dev = NULL;
146 goto skip_device;
147 }
148
149 entry = kcalloc(dev_header->prop_count + 1, sizeof(*entry),
150 GFP_KERNEL);
151 if (!entry) {
152 dev_err(dev, "cannot allocate properties\n");
153 goto skip_device;
154 }
155
156 unmarshal_key_value_pairs(dev_header, dev, ptr, entry);
157 if (!entry[0].name)
158 goto skip_device;
159
160 ret = device_create_managed_software_node(dev, entry, NULL);
161 if (ret)
162 dev_err(dev, "error %d assigning properties\n", ret);
163
164 for (i = 0; entry[i].name; i++)
165 kfree(entry[i].name);
166
167skip_device:
168 kfree(entry);
169 put_device(dev);
170 offset += dev_header->len;
171 }
172
173 return 0;
174}
175
176static int __init map_properties(void)
177{
178 struct properties_header *properties;
179 struct setup_data *data;
180 u32 data_len;
181 u64 pa_data;
182 int ret;
183
184 if (!x86_apple_machine)
185 return 0;
186
187 pa_data = boot_params.hdr.setup_data;
188 while (pa_data) {
189 data = memremap(pa_data, sizeof(*data), MEMREMAP_WB);
190 if (!data) {
191 pr_err("cannot map setup_data header\n");
192 return -ENOMEM;
193 }
194
195 if (data->type != SETUP_APPLE_PROPERTIES) {
196 pa_data = data->next;
197 memunmap(data);
198 continue;
199 }
200
201 data_len = data->len;
202 memunmap(data);
203
204 data = memremap(pa_data, sizeof(*data) + data_len, MEMREMAP_WB);
205 if (!data) {
206 pr_err("cannot map setup_data payload\n");
207 return -ENOMEM;
208 }
209
210 properties = (struct properties_header *)data->data;
211 if (properties->version != 1) {
212 pr_err("unsupported version:\n");
213 print_hex_dump(KERN_ERR, pr_fmt(), DUMP_PREFIX_OFFSET,
214 16, 1, properties, data_len, true);
215 ret = -ENOTSUPP;
216 } else if (properties->len != data_len) {
217 pr_err("length mismatch, expected %u\n", data_len);
218 print_hex_dump(KERN_ERR, pr_fmt(), DUMP_PREFIX_OFFSET,
219 16, 1, properties, data_len, true);
220 ret = -EINVAL;
221 } else
222 ret = unmarshal_devices(properties);
223
224 /*
225 * Can only free the setup_data payload but not its header
226 * to avoid breaking the chain of ->next pointers.
227 */
228 data->len = 0;
229 memunmap(data);
230 memblock_free_late(pa_data + sizeof(*data), data_len);
231
232 return ret;
233 }
234 return 0;
235}
236
237fs_initcall(map_properties);