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                 struct efi_device_path_vendor *vdp =
  64                         (struct efi_device_path_vendor *)dp;
  65                 s += sprintf(s, "VenHw(%pUl)", &vdp->guid);
  66                 break;
  67         }
  68         default:
  69                 s = dp_unknown(s, dp);
  70                 break;
  71         }
  72         return s;
  73 }
  74
  75 static char *dp_acpi(char *s, struct efi_device_path *dp)
  76 {
  77         switch (dp->sub_type) {
  78         case DEVICE_PATH_SUB_TYPE_ACPI_DEVICE: {
  79                 struct efi_device_path_acpi_path *adp =
  80                         (struct efi_device_path_acpi_path *)dp;
  81
  82                 s += sprintf(s, "Acpi(PNP%04X,%d)", EISA_PNP_NUM(adp->hid),
  83                              adp->uid);
  84                 break;
  85         }
  86         default:
  87                 s = dp_unknown(s, dp);
  88                 break;
  89         }
  90         return s;
  91 }
  92
  93 static char *dp_msging(char *s, struct efi_device_path *dp)
  94 {
  95         switch (dp->sub_type) {
  96         case DEVICE_PATH_SUB_TYPE_MSG_ATAPI: {
  97                 struct efi_device_path_atapi *ide =
  98                         (struct efi_device_path_atapi *)dp;
  99                 s += sprintf(s, "Ata(%d,%d,%d)", ide->primary_secondary,
 100                              ide->slave_master, ide->logical_unit_number);
 101                 break;
 102         }
 103         case DEVICE_PATH_SUB_TYPE_MSG_SCSI: {
 104                 struct efi_device_path_scsi *ide =
 105                         (struct efi_device_path_scsi *)dp;
 106                 s += sprintf(s, "Scsi(%u,%u)", ide->target_id,
 107                              ide->logical_unit_number);
 108                 break;
 109         }
 110         case DEVICE_PATH_SUB_TYPE_MSG_USB: {
 111                 struct efi_device_path_usb *udp =
 112                         (struct efi_device_path_usb *)dp;
 113                 s += sprintf(s, "USB(0x%x,0x%x)", udp->parent_port_number,
 114                              udp->usb_interface);
 115                 break;
 116         }
 117         case DEVICE_PATH_SUB_TYPE_MSG_MAC_ADDR: {
 118                 struct efi_device_path_mac_addr *mdp =
 119                         (struct efi_device_path_mac_addr *)dp;
 120
 121                 if (mdp->if_type != 0 && mdp->if_type != 1)
 122                         break;
 123
 124                 s += sprintf(s, "MAC(%02x%02x%02x%02x%02x%02x,0x%1x)",
 125                         mdp->mac.addr[0], mdp->mac.addr[1],
 126                         mdp->mac.addr[2], mdp->mac.addr[3],
 127                         mdp->mac.addr[4], mdp->mac.addr[5],
 128                         mdp->if_type);
 129
 130                 break;
 131         }
 132         case DEVICE_PATH_SUB_TYPE_MSG_USB_CLASS: {
 133                 struct efi_device_path_usb_class *ucdp =
 134                         (struct efi_device_path_usb_class *)dp;
 135
 136                 s += sprintf(s, "USBClass(%x,%x,%x,%x,%x)",
 137                         ucdp->vendor_id, ucdp->product_id,
 138                         ucdp->device_class, ucdp->device_subclass,
 139                         ucdp->device_protocol);
 140
 141                 break;
 142         }
 143         case DEVICE_PATH_SUB_TYPE_MSG_SD:
 144         case DEVICE_PATH_SUB_TYPE_MSG_MMC: {
 145                 const char *typename =
 146                         (dp->sub_type == DEVICE_PATH_SUB_TYPE_MSG_SD) ?
 147                                         "SD" : "eMMC";
 148                 struct efi_device_path_sd_mmc_path *sddp =
 149                         (struct efi_device_path_sd_mmc_path *)dp;
 150                 s += sprintf(s, "%s(%u)", typename, sddp->slot_number);
 151                 break;
 152         }
 153         default:
 154                 s = dp_unknown(s, dp);
 155                 break;
 156         }
 157         return s;
 158 }
 159
 160 /*
 161  * Convert a media device path node to text.
 162  *
 163  * @s           output buffer
 164  * @dp          device path node
 165  * @return      next unused buffer address
 166  */
 167 static char *dp_media(char *s, struct efi_device_path *dp)
 168 {
 169         switch (dp->sub_type) {
 170         case DEVICE_PATH_SUB_TYPE_HARD_DRIVE_PATH: {
 171                 struct efi_device_path_hard_drive_path *hddp =
 172                         (struct efi_device_path_hard_drive_path *)dp;
 173                 void *sig = hddp->partition_signature;
 174                 u64 start;
 175                 u64 end;
 176
 177                 /* Copy from packed structure to aligned memory */
 178                 memcpy(&start, &hddp->partition_start, sizeof(start));
 179                 memcpy(&end, &hddp->partition_end, sizeof(end));
 180
 181                 switch (hddp->signature_type) {
 182                 case SIG_TYPE_MBR: {
 183                         u32 signature;
 184
 185                         memcpy(&signature, sig, sizeof(signature));
 186                         s += sprintf(
 187                                 s, "HD(%d,MBR,0x%08x,0x%llx,0x%llx)",
 188                                 hddp->partition_number, signature, start, end);
 189                         break;
 190                         }
 191                 case SIG_TYPE_GUID:
 192                         s += sprintf(
 193                                 s, "HD(%d,GPT,%pUl,0x%llx,0x%llx)",
 194                                 hddp->partition_number, sig, start, end);
 195                         break;
 196                 default:
 197                         s += sprintf(
 198                                 s, "HD(%d,0x%02x,0,0x%llx,0x%llx)",
 199                                 hddp->partition_number, hddp->partmap_type,
 200                                 start, end);
 201                         break;
 202                 }
 203
 204                 break;
 205         }
 206         case DEVICE_PATH_SUB_TYPE_CDROM_PATH: {
 207                 struct efi_device_path_cdrom_path *cddp =
 208                         (struct efi_device_path_cdrom_path *)dp;
 209                 s += sprintf(s, "CDROM(0x%x)", cddp->boot_entry);
 210                 break;
 211         }
 212         case DEVICE_PATH_SUB_TYPE_FILE_PATH: {
 213                 struct efi_device_path_file_path *fp =
 214                         (struct efi_device_path_file_path *)dp;
 215                 int slen = (dp->length - sizeof(*dp)) / 2;
 216                 if (slen > MAX_NODE_LEN - 2)
 217                         slen = MAX_NODE_LEN - 2;
 218                 s += sprintf(s, "%-.*ls", slen, fp->str);
 219                 break;
 220         }
 221         default:
 222                 s = dp_unknown(s, dp);
 223                 break;
 224         }
 225         return s;
 226 }
 227
 228 /*
 229  * Converts a single node to a char string.
 230  *
 231  * @buffer              output buffer
 232  * @dp                  device path or node
 233  * @return              end of string
 234  */
 235 static char *efi_convert_single_device_node_to_text(
 236                 char *buffer,
 237                 struct efi_device_path *dp)
 238 {
 239         char *str = buffer;
 240
 241         switch (dp->type) {
 242         case DEVICE_PATH_TYPE_HARDWARE_DEVICE:
 243                 str = dp_hardware(str, dp);
 244                 break;
 245         case DEVICE_PATH_TYPE_ACPI_DEVICE:
 246                 str = dp_acpi(str, dp);
 247                 break;
 248         case DEVICE_PATH_TYPE_MESSAGING_DEVICE:
 249                 str = dp_msging(str, dp);
 250                 break;
 251         case DEVICE_PATH_TYPE_MEDIA_DEVICE:
 252                 str = dp_media(str, dp);
 253                 break;
 254         case DEVICE_PATH_TYPE_END:
 255                 break;
 256         default:
 257                 str = dp_unknown(str, dp);
 258         }
 259
 260         *str = '\0';
 261         return str;
 262 }
 263
 264 /*
 265  * This function implements the ConvertDeviceNodeToText service of the
 266  * EFI_DEVICE_PATH_TO_TEXT_PROTOCOL.
 267  * See the Unified Extensible Firmware Interface (UEFI) specification
 268  * for details.
 269  *
 270  * device_node          device node to be converted
 271  * display_only         true if the shorter text representation shall be used
 272  * allow_shortcuts      true if shortcut forms may be used
 273  * @return              text representation of the device path
 274  *                      NULL if out of memory of device_path is NULL
 275  */
 276 static uint16_t EFIAPI *efi_convert_device_node_to_text(
 277                 struct efi_device_path *device_node,
 278                 bool display_only,
 279                 bool allow_shortcuts)
 280 {
 281         char str[MAX_NODE_LEN];
 282         uint16_t *text = NULL;
 283
 284         EFI_ENTRY("%p, %d, %d", device_node, display_only, allow_shortcuts);
 285
 286         if (!device_node)
 287                 goto out;
 288         efi_convert_single_device_node_to_text(str, device_node);
 289
 290         text = efi_str_to_u16(str);
 291
 292 out:
 293         EFI_EXIT(EFI_SUCCESS);
 294         return text;
 295 }
 296
 297 /*
 298  * This function implements the ConvertDevicePathToText service of the
 299  * EFI_DEVICE_PATH_TO_TEXT_PROTOCOL.
 300  * See the Unified Extensible Firmware Interface (UEFI) specification
 301  * for details.
 302  *
 303  * device_path          device path to be converted
 304  * display_only         true if the shorter text representation shall be used
 305  * allow_shortcuts      true if shortcut forms may be used
 306  * @return              text representation of the device path
 307  *                      NULL if out of memory of device_path is NULL
 308  */
 309 static uint16_t EFIAPI *efi_convert_device_path_to_text(
 310                 struct efi_device_path *device_path,
 311                 bool display_only,
 312                 bool allow_shortcuts)
 313 {
 314         uint16_t *text = NULL;
 315         char buffer[MAX_PATH_LEN];
 316         char *str = buffer;
 317
 318         EFI_ENTRY("%p, %d, %d", device_path, display_only, allow_shortcuts);
 319
 320         if (!device_path)
 321                 goto out;
 322         while (device_path &&
 323                str + MAX_NODE_LEN < buffer + MAX_PATH_LEN) {
 324                 *str++ = '/';
 325                 str = efi_convert_single_device_node_to_text(str, device_path);
 326                 device_path = efi_dp_next(device_path);
 327         }
 328
 329         text = efi_str_to_u16(buffer);
 330
 331 out:
 332         EFI_EXIT(EFI_SUCCESS);
 333         return text;
 334 }
 335
 336 /* helper for debug prints.. efi_free_pool() the result. */
 337 uint16_t *efi_dp_str(struct efi_device_path *dp)
 338 {
 339         return EFI_CALL(efi_convert_device_path_to_text(dp, true, true));
 340 }
 341
 342 const struct efi_device_path_to_text_protocol efi_device_path_to_text = {
 343         .convert_device_node_to_text = efi_convert_device_node_to_text,
 344         .convert_device_path_to_text = efi_convert_device_path_to_text,
 345 };