lib/efi_loader/efi_device_path_to_text.c

   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 <efi_loader.h>
  10
  11 #define MAC_OUTPUT_LEN 22
  12 #define UNKNOWN_OUTPUT_LEN 23
  13
  14 #define MAX_NODE_LEN 512
  15 #define MAX_PATH_LEN 1024
  16
  17 const efi_guid_t efi_guid_device_path_to_text_protocol =
  18                 EFI_DEVICE_PATH_TO_TEXT_PROTOCOL_GUID;
  19
  20 /**
  21  * efi_str_to_u16() - convert ASCII string to UTF-16
  22  *
  23  * A u16 buffer is allocated from pool. The ASCII string is copied to the u16
  24  * buffer.
  25  *
  26  * @str:        ASCII string
  27  * Return:      UTF-16 string. NULL if out of memory.
  28  */
  29 static u16 *efi_str_to_u16(char *str)
  30 {
  31         efi_uintn_t len;
  32         u16 *out;
  33         efi_status_t ret;
  34
  35         len = strlen(str) + 1;
  36         ret = efi_allocate_pool(EFI_ALLOCATE_ANY_PAGES, len * sizeof(u16),
  37                                 (void **)&out);
  38         if (ret != EFI_SUCCESS)
  39                 return NULL;
  40         ascii2unicode(out, str);
  41         return out;
  42 }
  43
  44 static char *dp_unknown(char *s, struct efi_device_path *dp)
  45 {
  46         s += sprintf(s, "UNKNOWN(%04x,%04x)", dp->type, dp->sub_type);
  47         return s;
  48 }
  49
  50 static char *dp_hardware(char *s, struct efi_device_path *dp)
  51 {
  52         switch (dp->sub_type) {
  53         case DEVICE_PATH_SUB_TYPE_MEMORY: {
  54                 struct efi_device_path_memory *mdp =
  55                         (struct efi_device_path_memory *)dp;
  56                 s += sprintf(s, "MemoryMapped(0x%x,0x%llx,0x%llx)",
  57                              mdp->memory_type,
  58                              mdp->start_address,
  59                              mdp->end_address);
  60                 break;
  61         }
  62         case DEVICE_PATH_SUB_TYPE_VENDOR: {
  63                 int i, n;
  64                 struct efi_device_path_vendor *vdp =
  65                         (struct efi_device_path_vendor *)dp;
  66
  67                 s += sprintf(s, "VenHw(%pUl", &vdp->guid);
  68                 n = (int)vdp->dp.length - sizeof(struct efi_device_path_vendor);
  69                 if (n > 0) {
  70                         s += sprintf(s, ",");
  71                         for (i = 0; i < n; ++i)
  72                                 s += sprintf(s, "%02x", vdp->vendor_data[i]);
  73                 }
  74                 s += sprintf(s, ")");
  75                 break;
  76         }
  77         default:
  78                 s = dp_unknown(s, dp);
  79                 break;
  80         }
  81         return s;
  82 }
  83
  84 static char *dp_acpi(char *s, struct efi_device_path *dp)
  85 {
  86         switch (dp->sub_type) {
  87         case DEVICE_PATH_SUB_TYPE_ACPI_DEVICE: {
  88                 struct efi_device_path_acpi_path *adp =
  89                         (struct efi_device_path_acpi_path *)dp;
  90
  91                 s += sprintf(s, "Acpi(PNP%04X,%d)", EISA_PNP_NUM(adp->hid),
  92                              adp->uid);
  93                 break;
  94         }
  95         default:
  96                 s = dp_unknown(s, dp);
  97                 break;
  98         }
  99         return s;
 100 }
 101
 102 static char *dp_msging(char *s, struct efi_device_path *dp)
 103 {
 104         switch (dp->sub_type) {
 105         case DEVICE_PATH_SUB_TYPE_MSG_ATAPI: {
 106                 struct efi_device_path_atapi *ide =
 107                         (struct efi_device_path_atapi *)dp;
 108                 s += sprintf(s, "Ata(%d,%d,%d)", ide->primary_secondary,
 109                              ide->slave_master, ide->logical_unit_number);
 110                 break;
 111         }
 112         case DEVICE_PATH_SUB_TYPE_MSG_SCSI: {
 113                 struct efi_device_path_scsi *ide =
 114                         (struct efi_device_path_scsi *)dp;
 115                 s += sprintf(s, "Scsi(%u,%u)", ide->target_id,
 116                              ide->logical_unit_number);
 117                 break;
 118         }
 119         case DEVICE_PATH_SUB_TYPE_MSG_USB: {
 120                 struct efi_device_path_usb *udp =
 121                         (struct efi_device_path_usb *)dp;
 122                 s += sprintf(s, "USB(0x%x,0x%x)", udp->parent_port_number,
 123                              udp->usb_interface);
 124                 break;
 125         }
 126         case DEVICE_PATH_SUB_TYPE_MSG_MAC_ADDR: {
 127                 int i, n = sizeof(struct efi_mac_addr);
 128                 struct efi_device_path_mac_addr *mdp =
 129                         (struct efi_device_path_mac_addr *)dp;
 130
 131                 if (mdp->if_type <= 1)
 132                         n = 6;
 133                 s += sprintf(s, "MAC(");
 134                 for (i = 0; i < n; ++i)
 135                         s += sprintf(s, "%02x", mdp->mac.addr[i]);
 136                 s += sprintf(s, ",%u)", mdp->if_type);
 137
 138                 break;
 139         }
 140         case DEVICE_PATH_SUB_TYPE_MSG_USB_CLASS: {
 141                 struct efi_device_path_usb_class *ucdp =
 142                         (struct efi_device_path_usb_class *)dp;
 143
 144                 s += sprintf(s, "USBClass(%x,%x,%x,%x,%x)",
 145                         ucdp->vendor_id, ucdp->product_id,
 146                         ucdp->device_class, ucdp->device_subclass,
 147                         ucdp->device_protocol);
 148
 149                 break;
 150         }
 151         case DEVICE_PATH_SUB_TYPE_MSG_SD:
 152         case DEVICE_PATH_SUB_TYPE_MSG_MMC: {
 153                 const char *typename =
 154                         (dp->sub_type == DEVICE_PATH_SUB_TYPE_MSG_SD) ?
 155                                         "SD" : "eMMC";
 156                 struct efi_device_path_sd_mmc_path *sddp =
 157                         (struct efi_device_path_sd_mmc_path *)dp;
 158                 s += sprintf(s, "%s(%u)", typename, sddp->slot_number);
 159                 break;
 160         }
 161         default:
 162                 s = dp_unknown(s, dp);
 163                 break;
 164         }
 165         return s;
 166 }
 167
 168 /*
 169  * Convert a media device path node to text.
 170  *
 171  * @s           output buffer
 172  * @dp          device path node
 173  * @return      next unused buffer address
 174  */
 175 static char *dp_media(char *s, struct efi_device_path *dp)
 176 {
 177         switch (dp->sub_type) {
 178         case DEVICE_PATH_SUB_TYPE_HARD_DRIVE_PATH: {
 179                 struct efi_device_path_hard_drive_path *hddp =
 180                         (struct efi_device_path_hard_drive_path *)dp;
 181                 void *sig = hddp->partition_signature;
 182                 u64 start;
 183                 u64 end;
 184
 185                 /* Copy from packed structure to aligned memory */
 186                 memcpy(&start, &hddp->partition_start, sizeof(start));
 187                 memcpy(&end, &hddp->partition_end, sizeof(end));
 188
 189                 switch (hddp->signature_type) {
 190                 case SIG_TYPE_MBR: {
 191                         u32 signature;
 192
 193                         memcpy(&signature, sig, sizeof(signature));
 194                         s += sprintf(
 195                                 s, "HD(%d,MBR,0x%08x,0x%llx,0x%llx)",
 196                                 hddp->partition_number, signature, start, end);
 197                         break;
 198                         }
 199                 case SIG_TYPE_GUID:
 200                         s += sprintf(
 201                                 s, "HD(%d,GPT,%pUl,0x%llx,0x%llx)",
 202                                 hddp->partition_number, sig, start, end);
 203                         break;
 204                 default:
 205                         s += sprintf(
 206                                 s, "HD(%d,0x%02x,0,0x%llx,0x%llx)",
 207                                 hddp->partition_number, hddp->partmap_type,
 208                                 start, end);
 209                         break;
 210                 }
 211
 212                 break;
 213         }
 214         case DEVICE_PATH_SUB_TYPE_CDROM_PATH: {
 215                 struct efi_device_path_cdrom_path *cddp =
 216                         (struct efi_device_path_cdrom_path *)dp;
 217                 s += sprintf(s, "CDROM(%u,0x%llx,0x%llx)", cddp->boot_entry,
 218                              cddp->partition_start, cddp->partition_size);
 219                 break;
 220         }
 221         case DEVICE_PATH_SUB_TYPE_FILE_PATH: {
 222                 struct efi_device_path_file_path *fp =
 223                         (struct efi_device_path_file_path *)dp;
 224                 int slen = (dp->length - sizeof(*dp)) / 2;
 225                 if (slen > MAX_NODE_LEN - 2)
 226                         slen = MAX_NODE_LEN - 2;
 227                 s += sprintf(s, "%-.*ls", slen, fp->str);
 228                 break;
 229         }
 230         default:
 231                 s = dp_unknown(s, dp);
 232                 break;
 233         }
 234         return s;
 235 }
 236
 237 /*
 238  * Converts a single node to a char string.
 239  *
 240  * @buffer              output buffer
 241  * @dp                  device path or node
 242  * @return              end of string
 243  */
 244 static char *efi_convert_single_device_node_to_text(
 245                 char *buffer,
 246                 struct efi_device_path *dp)
 247 {
 248         char *str = buffer;
 249
 250         switch (dp->type) {
 251         case DEVICE_PATH_TYPE_HARDWARE_DEVICE:
 252                 str = dp_hardware(str, dp);
 253                 break;
 254         case DEVICE_PATH_TYPE_ACPI_DEVICE:
 255                 str = dp_acpi(str, dp);
 256                 break;
 257         case DEVICE_PATH_TYPE_MESSAGING_DEVICE:
 258                 str = dp_msging(str, dp);
 259                 break;
 260         case DEVICE_PATH_TYPE_MEDIA_DEVICE:
 261                 str = dp_media(str, dp);
 262                 break;
 263         case DEVICE_PATH_TYPE_END:
 264                 break;
 265         default:
 266                 str = dp_unknown(str, dp);
 267         }
 268
 269         *str = '\0';
 270         return str;
 271 }
 272
 273 /*
 274  * This function implements the ConvertDeviceNodeToText service of the
 275  * EFI_DEVICE_PATH_TO_TEXT_PROTOCOL.
 276  * See the Unified Extensible Firmware Interface (UEFI) specification
 277  * for details.
 278  *
 279  * device_node          device node to be converted
 280  * display_only         true if the shorter text representation shall be used
 281  * allow_shortcuts      true if shortcut forms may be used
 282  * @return              text representation of the device path
 283  *                      NULL if out of memory of device_path is NULL
 284  */
 285 static uint16_t EFIAPI *efi_convert_device_node_to_text(
 286                 struct efi_device_path *device_node,
 287                 bool display_only,
 288                 bool allow_shortcuts)
 289 {
 290         char str[MAX_NODE_LEN];
 291         uint16_t *text = NULL;
 292
 293         EFI_ENTRY("%p, %d, %d", device_node, display_only, allow_shortcuts);
 294
 295         if (!device_node)
 296                 goto out;
 297         efi_convert_single_device_node_to_text(str, device_node);
 298
 299         text = efi_str_to_u16(str);
 300
 301 out:
 302         EFI_EXIT(EFI_SUCCESS);
 303         return text;
 304 }
 305
 306 /*
 307  * This function implements the ConvertDevicePathToText service of the
 308  * EFI_DEVICE_PATH_TO_TEXT_PROTOCOL.
 309  * See the Unified Extensible Firmware Interface (UEFI) specification
 310  * for details.
 311  *
 312  * device_path          device path to be converted
 313  * display_only         true if the shorter text representation shall be used
 314  * allow_shortcuts      true if shortcut forms may be used
 315  * @return              text representation of the device path
 316  *                      NULL if out of memory of device_path is NULL
 317  */
 318 static uint16_t EFIAPI *efi_convert_device_path_to_text(
 319                 struct efi_device_path *device_path,
 320                 bool display_only,
 321                 bool allow_shortcuts)
 322 {
 323         uint16_t *text = NULL;
 324         char buffer[MAX_PATH_LEN];
 325         char *str = buffer;
 326
 327         EFI_ENTRY("%p, %d, %d", device_path, display_only, allow_shortcuts);
 328
 329         if (!device_path)
 330                 goto out;
 331         while (device_path &&
 332                str + MAX_NODE_LEN < buffer + MAX_PATH_LEN) {
 333                 *str++ = '/';
 334                 str = efi_convert_single_device_node_to_text(str, device_path);
 335                 device_path = efi_dp_next(device_path);
 336         }
 337
 338         text = efi_str_to_u16(buffer);
 339
 340 out:
 341         EFI_EXIT(EFI_SUCCESS);
 342         return text;
 343 }
 344
 345 /* helper for debug prints.. efi_free_pool() the result. */
 346 uint16_t *efi_dp_str(struct efi_device_path *dp)
 347 {
 348         return EFI_CALL(efi_convert_device_path_to_text(dp, true, true));
 349 }
 350
 351 const struct efi_device_path_to_text_protocol efi_device_path_to_text = {
 352         .convert_device_node_to_text = efi_convert_device_node_to_text,
 353         .convert_device_path_to_text = efi_convert_device_path_to_text,
 354 };