1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  *  EFI device path interface
4  *
5  *  Copyright (c) 2017 Heinrich Schuchardt
6  */
7 
8 #include <common.h>
9 #include <blk.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 /**
22  * efi_str_to_u16() - convert ASCII string to UTF-16
23  *
24  * A u16 buffer is allocated from pool. The ASCII string is copied to the u16
25  * buffer.
26  *
27  * @str:	ASCII string
28  * Return:	UTF-16 string. NULL if out of memory.
29  */
efi_str_to_u16(char * str)30 static u16 *efi_str_to_u16(char *str)
31 {
32 	efi_uintn_t len;
33 	u16 *out, *dst;
34 	efi_status_t ret;
35 
36 	len = sizeof(u16) * (utf8_utf16_strlen(str) + 1);
37 	ret = efi_allocate_pool(EFI_BOOT_SERVICES_DATA, len, (void **)&out);
38 	if (ret != EFI_SUCCESS)
39 		return NULL;
40 	dst = out;
41 	utf8_utf16_strcpy(&dst, str);
42 	return out;
43 }
44 
dp_unknown(char * s,struct efi_device_path * dp)45 static char *dp_unknown(char *s, struct efi_device_path *dp)
46 {
47 	s += sprintf(s, "UNKNOWN(%04x,%04x)", dp->type, dp->sub_type);
48 	return s;
49 }
50 
dp_hardware(char * s,struct efi_device_path * dp)51 static char *dp_hardware(char *s, struct efi_device_path *dp)
52 {
53 	switch (dp->sub_type) {
54 	case DEVICE_PATH_SUB_TYPE_MEMORY: {
55 		struct efi_device_path_memory *mdp =
56 			(struct efi_device_path_memory *)dp;
57 		s += sprintf(s, "MemoryMapped(0x%x,0x%llx,0x%llx)",
58 			     mdp->memory_type,
59 			     mdp->start_address,
60 			     mdp->end_address);
61 		break;
62 	}
63 	case DEVICE_PATH_SUB_TYPE_VENDOR: {
64 		int i, n;
65 		struct efi_device_path_vendor *vdp =
66 			(struct efi_device_path_vendor *)dp;
67 
68 		s += sprintf(s, "VenHw(%pUl", &vdp->guid);
69 		n = (int)vdp->dp.length - sizeof(struct efi_device_path_vendor);
70 		/* Node must fit into MAX_NODE_LEN) */
71 		if (n > 0 && n < MAX_NODE_LEN / 2 - 22) {
72 			s += sprintf(s, ",");
73 			for (i = 0; i < n; ++i)
74 				s += sprintf(s, "%02x", vdp->vendor_data[i]);
75 		}
76 		s += sprintf(s, ")");
77 		break;
78 	}
79 	default:
80 		s = dp_unknown(s, dp);
81 		break;
82 	}
83 	return s;
84 }
85 
dp_acpi(char * s,struct efi_device_path * dp)86 static char *dp_acpi(char *s, struct efi_device_path *dp)
87 {
88 	switch (dp->sub_type) {
89 	case DEVICE_PATH_SUB_TYPE_ACPI_DEVICE: {
90 		struct efi_device_path_acpi_path *adp =
91 			(struct efi_device_path_acpi_path *)dp;
92 
93 		s += sprintf(s, "Acpi(PNP%04X,%d)", EISA_PNP_NUM(adp->hid),
94 			     adp->uid);
95 		break;
96 	}
97 	default:
98 		s = dp_unknown(s, dp);
99 		break;
100 	}
101 	return s;
102 }
103 
dp_msging(char * s,struct efi_device_path * dp)104 static char *dp_msging(char *s, struct efi_device_path *dp)
105 {
106 	switch (dp->sub_type) {
107 	case DEVICE_PATH_SUB_TYPE_MSG_ATAPI: {
108 		struct efi_device_path_atapi *ide =
109 			(struct efi_device_path_atapi *)dp;
110 		s += sprintf(s, "Ata(%d,%d,%d)", ide->primary_secondary,
111 			     ide->slave_master, ide->logical_unit_number);
112 		break;
113 	}
114 	case DEVICE_PATH_SUB_TYPE_MSG_SCSI: {
115 		struct efi_device_path_scsi *ide =
116 			(struct efi_device_path_scsi *)dp;
117 		s += sprintf(s, "Scsi(%u,%u)", ide->target_id,
118 			     ide->logical_unit_number);
119 		break;
120 	}
121 	case DEVICE_PATH_SUB_TYPE_MSG_UART: {
122 		struct efi_device_path_uart *uart =
123 			(struct efi_device_path_uart *)dp;
124 		s += sprintf(s, "Uart(%lld,%d,%d,", uart->baud_rate,
125 			     uart->data_bits, uart->parity);
126 		switch (uart->stop_bits) {
127 		case 2:
128 			s += sprintf(s, "1.5)");
129 			break;
130 		default:
131 			s += sprintf(s, "%d)", uart->stop_bits);
132 			break;
133 		}
134 		break;
135 	}
136 	case DEVICE_PATH_SUB_TYPE_MSG_USB: {
137 		struct efi_device_path_usb *udp =
138 			(struct efi_device_path_usb *)dp;
139 		s += sprintf(s, "USB(0x%x,0x%x)", udp->parent_port_number,
140 			     udp->usb_interface);
141 		break;
142 	}
143 	case DEVICE_PATH_SUB_TYPE_MSG_MAC_ADDR: {
144 		int i, n = sizeof(struct efi_mac_addr);
145 		struct efi_device_path_mac_addr *mdp =
146 			(struct efi_device_path_mac_addr *)dp;
147 
148 		if (mdp->if_type <= 1)
149 			n = 6;
150 		s += sprintf(s, "MAC(");
151 		for (i = 0; i < n; ++i)
152 			s += sprintf(s, "%02x", mdp->mac.addr[i]);
153 		s += sprintf(s, ",%u)", mdp->if_type);
154 
155 		break;
156 	}
157 	case DEVICE_PATH_SUB_TYPE_MSG_USB_CLASS: {
158 		struct efi_device_path_usb_class *ucdp =
159 			(struct efi_device_path_usb_class *)dp;
160 
161 		s += sprintf(s, "UsbClass(0x%x,0x%x,0x%x,0x%x,0x%x)",
162 			ucdp->vendor_id, ucdp->product_id,
163 			ucdp->device_class, ucdp->device_subclass,
164 			ucdp->device_protocol);
165 
166 		break;
167 	}
168 	case DEVICE_PATH_SUB_TYPE_MSG_SATA: {
169 		struct efi_device_path_sata *sdp =
170 			(struct efi_device_path_sata *) dp;
171 
172 		s += sprintf(s, "Sata(0x%x,0x%x,0x%x)",
173 			     sdp->hba_port,
174 			     sdp->port_multiplier_port,
175 			     sdp->logical_unit_number);
176 		break;
177 	}
178 	case DEVICE_PATH_SUB_TYPE_MSG_NVME: {
179 		struct efi_device_path_nvme *ndp =
180 			(struct efi_device_path_nvme *)dp;
181 		u32 ns_id;
182 		int i;
183 
184 		memcpy(&ns_id, &ndp->ns_id, sizeof(ns_id));
185 		s += sprintf(s, "NVMe(0x%x,", ns_id);
186 		for (i = 0; i < sizeof(ndp->eui64); ++i)
187 			s += sprintf(s, "%s%02x", i ? "-" : "",
188 				     ndp->eui64[i]);
189 		s += sprintf(s, ")");
190 
191 		break;
192 	}
193 	case DEVICE_PATH_SUB_TYPE_MSG_URI: {
194 		struct efi_device_path_uri *udp =
195 			(struct efi_device_path_uri *)dp;
196 		int n;
197 
198 		n = (int)udp->dp.length - sizeof(struct efi_device_path_uri);
199 
200 		s += sprintf(s, "Uri(");
201 		if (n > 0 && n < MAX_NODE_LEN - 6)
202 			s += snprintf(s, n, "%s", (char *)udp->uri);
203 		s += sprintf(s, ")");
204 		break;
205 	}
206 	case DEVICE_PATH_SUB_TYPE_MSG_SD:
207 	case DEVICE_PATH_SUB_TYPE_MSG_MMC: {
208 		const char *typename =
209 			(dp->sub_type == DEVICE_PATH_SUB_TYPE_MSG_SD) ?
210 					"SD" : "eMMC";
211 		struct efi_device_path_sd_mmc_path *sddp =
212 			(struct efi_device_path_sd_mmc_path *)dp;
213 		s += sprintf(s, "%s(%u)", typename, sddp->slot_number);
214 		break;
215 	}
216 	default:
217 		s = dp_unknown(s, dp);
218 		break;
219 	}
220 	return s;
221 }
222 
223 /*
224  * Convert a media device path node to text.
225  *
226  * @s		output buffer
227  * @dp		device path node
228  * @return	next unused buffer address
229  */
dp_media(char * s,struct efi_device_path * dp)230 static char *dp_media(char *s, struct efi_device_path *dp)
231 {
232 	switch (dp->sub_type) {
233 	case DEVICE_PATH_SUB_TYPE_HARD_DRIVE_PATH: {
234 		struct efi_device_path_hard_drive_path *hddp =
235 			(struct efi_device_path_hard_drive_path *)dp;
236 		void *sig = hddp->partition_signature;
237 		u64 start;
238 		u64 end;
239 
240 		/* Copy from packed structure to aligned memory */
241 		memcpy(&start, &hddp->partition_start, sizeof(start));
242 		memcpy(&end, &hddp->partition_end, sizeof(end));
243 
244 		switch (hddp->signature_type) {
245 		case SIG_TYPE_MBR: {
246 			u32 signature;
247 
248 			memcpy(&signature, sig, sizeof(signature));
249 			s += sprintf(
250 				s, "HD(%d,MBR,0x%08x,0x%llx,0x%llx)",
251 				hddp->partition_number, signature, start, end);
252 			break;
253 			}
254 		case SIG_TYPE_GUID:
255 			s += sprintf(
256 				s, "HD(%d,GPT,%pUl,0x%llx,0x%llx)",
257 				hddp->partition_number, sig, start, end);
258 			break;
259 		default:
260 			s += sprintf(
261 				s, "HD(%d,0x%02x,0,0x%llx,0x%llx)",
262 				hddp->partition_number, hddp->partmap_type,
263 				start, end);
264 			break;
265 		}
266 
267 		break;
268 	}
269 	case DEVICE_PATH_SUB_TYPE_CDROM_PATH: {
270 		struct efi_device_path_cdrom_path *cddp =
271 			(struct efi_device_path_cdrom_path *)dp;
272 		s += sprintf(s, "CDROM(%u,0x%llx,0x%llx)", cddp->boot_entry,
273 			     cddp->partition_start, cddp->partition_size);
274 		break;
275 	}
276 	case DEVICE_PATH_SUB_TYPE_VENDOR_PATH: {
277 		int i, n;
278 		struct efi_device_path_vendor *vdp =
279 			(struct efi_device_path_vendor *)dp;
280 
281 		s += sprintf(s, "VenMedia(%pUl", &vdp->guid);
282 		n = (int)vdp->dp.length - sizeof(struct efi_device_path_vendor);
283 		/* Node must fit into MAX_NODE_LEN) */
284 		if (n > 0 && n < MAX_NODE_LEN / 2 - 24) {
285 			s += sprintf(s, ",");
286 			for (i = 0; i < n; ++i)
287 				s += sprintf(s, "%02x", vdp->vendor_data[i]);
288 		}
289 		s += sprintf(s, ")");
290 		break;
291 	}
292 	case DEVICE_PATH_SUB_TYPE_FILE_PATH: {
293 		struct efi_device_path_file_path *fp =
294 			(struct efi_device_path_file_path *)dp;
295 		int slen = (dp->length - sizeof(*dp)) / 2;
296 		if (slen > MAX_NODE_LEN - 2)
297 			slen = MAX_NODE_LEN - 2;
298 		s += sprintf(s, "%-.*ls", slen, fp->str);
299 		break;
300 	}
301 	default:
302 		s = dp_unknown(s, dp);
303 		break;
304 	}
305 	return s;
306 }
307 
308 /*
309  * Converts a single node to a char string.
310  *
311  * @buffer		output buffer
312  * @dp			device path or node
313  * @return		end of string
314  */
efi_convert_single_device_node_to_text(char * buffer,struct efi_device_path * dp)315 static char *efi_convert_single_device_node_to_text(
316 		char *buffer,
317 		struct efi_device_path *dp)
318 {
319 	char *str = buffer;
320 
321 	switch (dp->type) {
322 	case DEVICE_PATH_TYPE_HARDWARE_DEVICE:
323 		str = dp_hardware(str, dp);
324 		break;
325 	case DEVICE_PATH_TYPE_ACPI_DEVICE:
326 		str = dp_acpi(str, dp);
327 		break;
328 	case DEVICE_PATH_TYPE_MESSAGING_DEVICE:
329 		str = dp_msging(str, dp);
330 		break;
331 	case DEVICE_PATH_TYPE_MEDIA_DEVICE:
332 		str = dp_media(str, dp);
333 		break;
334 	case DEVICE_PATH_TYPE_END:
335 		break;
336 	default:
337 		str = dp_unknown(str, dp);
338 	}
339 
340 	*str = '\0';
341 	return str;
342 }
343 
344 /*
345  * This function implements the ConvertDeviceNodeToText service of the
346  * EFI_DEVICE_PATH_TO_TEXT_PROTOCOL.
347  * See the Unified Extensible Firmware Interface (UEFI) specification
348  * for details.
349  *
350  * device_node		device node to be converted
351  * display_only		true if the shorter text representation shall be used
352  * allow_shortcuts	true if shortcut forms may be used
353  * @return		text representation of the device path
354  *			NULL if out of memory of device_path is NULL
355  */
efi_convert_device_node_to_text(struct efi_device_path * device_node,bool display_only,bool allow_shortcuts)356 static uint16_t EFIAPI *efi_convert_device_node_to_text(
357 		struct efi_device_path *device_node,
358 		bool display_only,
359 		bool allow_shortcuts)
360 {
361 	char str[MAX_NODE_LEN];
362 	uint16_t *text = NULL;
363 
364 	EFI_ENTRY("%p, %d, %d", device_node, display_only, allow_shortcuts);
365 
366 	if (!device_node)
367 		goto out;
368 	efi_convert_single_device_node_to_text(str, device_node);
369 
370 	text = efi_str_to_u16(str);
371 
372 out:
373 	EFI_EXIT(EFI_SUCCESS);
374 	return text;
375 }
376 
377 /*
378  * This function implements the ConvertDevicePathToText service of the
379  * EFI_DEVICE_PATH_TO_TEXT_PROTOCOL.
380  * See the Unified Extensible Firmware Interface (UEFI) specification
381  * for details.
382  *
383  * device_path		device path to be converted
384  * display_only		true if the shorter text representation shall be used
385  * allow_shortcuts	true if shortcut forms may be used
386  * @return		text representation of the device path
387  *			NULL if out of memory of device_path is NULL
388  */
efi_convert_device_path_to_text(struct efi_device_path * device_path,bool display_only,bool allow_shortcuts)389 static uint16_t EFIAPI *efi_convert_device_path_to_text(
390 		struct efi_device_path *device_path,
391 		bool display_only,
392 		bool allow_shortcuts)
393 {
394 	uint16_t *text = NULL;
395 	char buffer[MAX_PATH_LEN];
396 	char *str = buffer;
397 
398 	EFI_ENTRY("%p, %d, %d", device_path, display_only, allow_shortcuts);
399 
400 	if (!device_path)
401 		goto out;
402 	while (device_path && str + MAX_NODE_LEN < buffer + MAX_PATH_LEN) {
403 		if (device_path->type == DEVICE_PATH_TYPE_END) {
404 			if (device_path->sub_type !=
405 			    DEVICE_PATH_SUB_TYPE_INSTANCE_END)
406 				break;
407 			*str++ = ',';
408 		} else {
409 			*str++ = '/';
410 			str = efi_convert_single_device_node_to_text(
411 							str, device_path);
412 		}
413 		*(u8 **)&device_path += device_path->length;
414 	}
415 
416 	text = efi_str_to_u16(buffer);
417 
418 out:
419 	EFI_EXIT(EFI_SUCCESS);
420 	return text;
421 }
422 
423 /* helper for debug prints.. efi_free_pool() the result. */
efi_dp_str(struct efi_device_path * dp)424 uint16_t *efi_dp_str(struct efi_device_path *dp)
425 {
426 	return EFI_CALL(efi_convert_device_path_to_text(dp, true, true));
427 }
428 
429 const struct efi_device_path_to_text_protocol efi_device_path_to_text = {
430 	.convert_device_node_to_text = efi_convert_device_node_to_text,
431 	.convert_device_path_to_text = efi_convert_device_path_to_text,
432 };
433