1 /*
2  *  EFI device path interface
3  *
4  *  Copyright (c) 2017 Heinrich Schuchardt
5  *
6  *  SPDX-License-Identifier:     GPL-2.0+
7  */
8 
9 #include <common.h>
10 #include <efi_loader.h>
11 
12 #define MAC_OUTPUT_LEN 22
13 #define UNKNOWN_OUTPUT_LEN 23
14 
15 #define MAX_NODE_LEN 512
16 #define MAX_PATH_LEN 1024
17 
18 const efi_guid_t efi_guid_device_path_to_text_protocol =
19 		EFI_DEVICE_PATH_TO_TEXT_PROTOCOL_GUID;
20 
21 static u16 *efi_str_to_u16(char *str)
22 {
23 	efi_uintn_t len;
24 	u16 *out;
25 	efi_status_t ret;
26 
27 	len = strlen(str) + 1;
28 	ret = efi_allocate_pool(EFI_ALLOCATE_ANY_PAGES, len * sizeof(u16),
29 				(void **)&out);
30 	if (ret != EFI_SUCCESS)
31 		return NULL;
32 	ascii2unicode(out, str);
33 	out[len - 1] = 0;
34 	return out;
35 }
36 
37 static char *dp_unknown(char *s, struct efi_device_path *dp)
38 {
39 	s += sprintf(s, "UNKNOWN(%04x,%04x)", dp->type, dp->sub_type);
40 	return s;
41 }
42 
43 static char *dp_hardware(char *s, struct efi_device_path *dp)
44 {
45 	switch (dp->sub_type) {
46 	case DEVICE_PATH_SUB_TYPE_MEMORY: {
47 		struct efi_device_path_memory *mdp =
48 			(struct efi_device_path_memory *)dp;
49 		s += sprintf(s, "MemoryMapped(0x%x,0x%llx,0x%llx)",
50 			     mdp->memory_type,
51 			     mdp->start_address,
52 			     mdp->end_address);
53 		break;
54 	}
55 	case DEVICE_PATH_SUB_TYPE_VENDOR: {
56 		struct efi_device_path_vendor *vdp =
57 			(struct efi_device_path_vendor *)dp;
58 		s += sprintf(s, "VenHw(%pUl)", &vdp->guid);
59 		break;
60 	}
61 	default:
62 		s = dp_unknown(s, dp);
63 		break;
64 	}
65 	return s;
66 }
67 
68 static char *dp_acpi(char *s, struct efi_device_path *dp)
69 {
70 	switch (dp->sub_type) {
71 	case DEVICE_PATH_SUB_TYPE_ACPI_DEVICE: {
72 		struct efi_device_path_acpi_path *adp =
73 			(struct efi_device_path_acpi_path *)dp;
74 		s += sprintf(s, "Acpi(PNP%04x", EISA_PNP_NUM(adp->hid));
75 		if (adp->uid)
76 			s += sprintf(s, ",%d", adp->uid);
77 		s += sprintf(s, ")");
78 		break;
79 	}
80 	default:
81 		s = dp_unknown(s, dp);
82 		break;
83 	}
84 	return s;
85 }
86 
87 static char *dp_msging(char *s, struct efi_device_path *dp)
88 {
89 	switch (dp->sub_type) {
90 	case DEVICE_PATH_SUB_TYPE_MSG_ATAPI: {
91 		struct efi_device_path_atapi *ide =
92 			(struct efi_device_path_atapi *)dp;
93 		s += sprintf(s, "Ata(%d,%d,%d)", ide->primary_secondary,
94 			     ide->slave_master, ide->logical_unit_number);
95 		break;
96 	}
97 	case DEVICE_PATH_SUB_TYPE_MSG_SCSI: {
98 		struct efi_device_path_scsi *ide =
99 			(struct efi_device_path_scsi *)dp;
100 		s += sprintf(s, "Scsi(%u,%u)", ide->target_id,
101 			     ide->logical_unit_number);
102 		break;
103 	}
104 	case DEVICE_PATH_SUB_TYPE_MSG_USB: {
105 		struct efi_device_path_usb *udp =
106 			(struct efi_device_path_usb *)dp;
107 		s += sprintf(s, "USB(0x%x,0x%x)", udp->parent_port_number,
108 			     udp->usb_interface);
109 		break;
110 	}
111 	case DEVICE_PATH_SUB_TYPE_MSG_MAC_ADDR: {
112 		struct efi_device_path_mac_addr *mdp =
113 			(struct efi_device_path_mac_addr *)dp;
114 
115 		if (mdp->if_type != 0 && mdp->if_type != 1)
116 			break;
117 
118 		s += sprintf(s, "MAC(%02x%02x%02x%02x%02x%02x,0x%1x)",
119 			mdp->mac.addr[0], mdp->mac.addr[1],
120 			mdp->mac.addr[2], mdp->mac.addr[3],
121 			mdp->mac.addr[4], mdp->mac.addr[5],
122 			mdp->if_type);
123 
124 		break;
125 	}
126 	case DEVICE_PATH_SUB_TYPE_MSG_USB_CLASS: {
127 		struct efi_device_path_usb_class *ucdp =
128 			(struct efi_device_path_usb_class *)dp;
129 
130 		s += sprintf(s, "USBClass(%x,%x,%x,%x,%x)",
131 			ucdp->vendor_id, ucdp->product_id,
132 			ucdp->device_class, ucdp->device_subclass,
133 			ucdp->device_protocol);
134 
135 		break;
136 	}
137 	case DEVICE_PATH_SUB_TYPE_MSG_SD:
138 	case DEVICE_PATH_SUB_TYPE_MSG_MMC: {
139 		const char *typename =
140 			(dp->sub_type == DEVICE_PATH_SUB_TYPE_MSG_SD) ?
141 					"SD" : "eMMC";
142 		struct efi_device_path_sd_mmc_path *sddp =
143 			(struct efi_device_path_sd_mmc_path *)dp;
144 		s += sprintf(s, "%s(%u)", typename, sddp->slot_number);
145 		break;
146 	}
147 	default:
148 		s = dp_unknown(s, dp);
149 		break;
150 	}
151 	return s;
152 }
153 
154 /*
155  * Convert a media device path node to text.
156  *
157  * @s		output buffer
158  * @dp		device path node
159  * @return	next unused buffer address
160  */
161 static char *dp_media(char *s, struct efi_device_path *dp)
162 {
163 	switch (dp->sub_type) {
164 	case DEVICE_PATH_SUB_TYPE_HARD_DRIVE_PATH: {
165 		struct efi_device_path_hard_drive_path *hddp =
166 			(struct efi_device_path_hard_drive_path *)dp;
167 		void *sig = hddp->partition_signature;
168 		u64 start;
169 		u64 end;
170 
171 		/* Copy from packed structure to aligned memory */
172 		memcpy(&start, &hddp->partition_start, sizeof(start));
173 		memcpy(&end, &hddp->partition_end, sizeof(end));
174 
175 		switch (hddp->signature_type) {
176 		case SIG_TYPE_MBR: {
177 			u32 signature;
178 
179 			memcpy(&signature, sig, sizeof(signature));
180 			s += sprintf(
181 				s, "HD(%d,MBR,0x%08x,0x%llx,0x%llx)",
182 				hddp->partition_number, signature, start, end);
183 			break;
184 			}
185 		case SIG_TYPE_GUID:
186 			s += sprintf(
187 				s, "HD(%d,GPT,%pUl,0x%llx,0x%llx)",
188 				hddp->partition_number, sig, start, end);
189 			break;
190 		default:
191 			s += sprintf(
192 				s, "HD(%d,0x%02x,0,0x%llx,0x%llx)",
193 				hddp->partition_number, hddp->partmap_type,
194 				start, end);
195 			break;
196 		}
197 
198 		break;
199 	}
200 	case DEVICE_PATH_SUB_TYPE_CDROM_PATH: {
201 		struct efi_device_path_cdrom_path *cddp =
202 			(struct efi_device_path_cdrom_path *)dp;
203 		s += sprintf(s, "CDROM(0x%x)", cddp->boot_entry);
204 		break;
205 	}
206 	case DEVICE_PATH_SUB_TYPE_FILE_PATH: {
207 		struct efi_device_path_file_path *fp =
208 			(struct efi_device_path_file_path *)dp;
209 		int slen = (dp->length - sizeof(*dp)) / 2;
210 		if (slen > MAX_NODE_LEN - 2)
211 			slen = MAX_NODE_LEN - 2;
212 		s += sprintf(s, "%-.*ls", slen, fp->str);
213 		break;
214 	}
215 	default:
216 		s = dp_unknown(s, dp);
217 		break;
218 	}
219 	return s;
220 }
221 
222 /*
223  * Converts a single node to a char string.
224  *
225  * @buffer		output buffer
226  * @dp			device path or node
227  * @return		end of string
228  */
229 static char *efi_convert_single_device_node_to_text(
230 		char *buffer,
231 		struct efi_device_path *dp)
232 {
233 	char *str = buffer;
234 
235 	switch (dp->type) {
236 	case DEVICE_PATH_TYPE_HARDWARE_DEVICE:
237 		str = dp_hardware(str, dp);
238 		break;
239 	case DEVICE_PATH_TYPE_ACPI_DEVICE:
240 		str = dp_acpi(str, dp);
241 		break;
242 	case DEVICE_PATH_TYPE_MESSAGING_DEVICE:
243 		str = dp_msging(str, dp);
244 		break;
245 	case DEVICE_PATH_TYPE_MEDIA_DEVICE:
246 		str = dp_media(str, dp);
247 		break;
248 	case DEVICE_PATH_TYPE_END:
249 		break;
250 	default:
251 		str = dp_unknown(str, dp);
252 	}
253 
254 	*str = '\0';
255 	return str;
256 }
257 
258 /*
259  * This function implements the ConvertDeviceNodeToText service of the
260  * EFI_DEVICE_PATH_TO_TEXT_PROTOCOL.
261  * See the Unified Extensible Firmware Interface (UEFI) specification
262  * for details.
263  *
264  * device_node		device node to be converted
265  * display_only		true if the shorter text represenation shall be used
266  * allow_shortcuts	true if shortcut forms may be used
267  * @return		text represenation of the device path
268  *			NULL if out of memory of device_path is NULL
269  */
270 static uint16_t EFIAPI *efi_convert_device_node_to_text(
271 		struct efi_device_path *device_node,
272 		bool display_only,
273 		bool allow_shortcuts)
274 {
275 	char str[MAX_NODE_LEN];
276 	uint16_t *text = NULL;
277 
278 	EFI_ENTRY("%p, %d, %d", device_node, display_only, allow_shortcuts);
279 
280 	if (!device_node)
281 		goto out;
282 	efi_convert_single_device_node_to_text(str, device_node);
283 
284 	text = efi_str_to_u16(str);
285 
286 out:
287 	EFI_EXIT(EFI_SUCCESS);
288 	return text;
289 }
290 
291 /*
292  * This function implements the ConvertDevicePathToText service of the
293  * EFI_DEVICE_PATH_TO_TEXT_PROTOCOL.
294  * See the Unified Extensible Firmware Interface (UEFI) specification
295  * for details.
296  *
297  * device_path		device path to be converted
298  * display_only		true if the shorter text represenation shall be used
299  * allow_shortcuts	true if shortcut forms may be used
300  * @return		text represenation of the device path
301  *			NULL if out of memory of device_path is NULL
302  */
303 static uint16_t EFIAPI *efi_convert_device_path_to_text(
304 		struct efi_device_path *device_path,
305 		bool display_only,
306 		bool allow_shortcuts)
307 {
308 	uint16_t *text = NULL;
309 	char buffer[MAX_PATH_LEN];
310 	char *str = buffer;
311 
312 	EFI_ENTRY("%p, %d, %d", device_path, display_only, allow_shortcuts);
313 
314 	if (!device_path)
315 		goto out;
316 	while (device_path &&
317 	       str + MAX_NODE_LEN < buffer + MAX_PATH_LEN) {
318 		*str++ = '/';
319 		str = efi_convert_single_device_node_to_text(str, device_path);
320 		device_path = efi_dp_next(device_path);
321 	}
322 
323 	text = efi_str_to_u16(buffer);
324 
325 out:
326 	EFI_EXIT(EFI_SUCCESS);
327 	return text;
328 }
329 
330 /* helper for debug prints.. efi_free_pool() the result. */
331 uint16_t *efi_dp_str(struct efi_device_path *dp)
332 {
333 	return EFI_CALL(efi_convert_device_path_to_text(dp, true, true));
334 }
335 
336 const struct efi_device_path_to_text_protocol efi_device_path_to_text = {
337 	.convert_device_node_to_text = efi_convert_device_node_to_text,
338 	.convert_device_path_to_text = efi_convert_device_path_to_text,
339 };
340