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                 s += sprintf(s, "Acpi(PNP%04x", EISA_PNP_NUM(adp->hid));
  82                 if (adp->uid)
  83                         s += sprintf(s, ",%d", adp->uid);
  84                 s += sprintf(s, ")");
  85                 break;
  86         }
  87         default:
  88                 s = dp_unknown(s, dp);
  89                 break;
  90         }
  91         return s;
  92 }
  93
  94 static char *dp_msging(char *s, struct efi_device_path *dp)
  95 {
  96         switch (dp->sub_type) {
  97         case DEVICE_PATH_SUB_TYPE_MSG_ATAPI: {
  98                 struct efi_device_path_atapi *ide =
  99                         (struct efi_device_path_atapi *)dp;
 100                 s += sprintf(s, "Ata(%d,%d,%d)", ide->primary_secondary,
 101                              ide->slave_master, ide->logical_unit_number);
 102                 break;
 103         }
 104         case DEVICE_PATH_SUB_TYPE_MSG_SCSI: {
 105                 struct efi_device_path_scsi *ide =
 106                         (struct efi_device_path_scsi *)dp;
 107                 s += sprintf(s, "Scsi(%u,%u)", ide->target_id,
 108                              ide->logical_unit_number);
 109                 break;
 110         }
 111         case DEVICE_PATH_SUB_TYPE_MSG_USB: {
 112                 struct efi_device_path_usb *udp =
 113                         (struct efi_device_path_usb *)dp;
 114                 s += sprintf(s, "USB(0x%x,0x%x)", udp->parent_port_number,
 115                              udp->usb_interface);
 116                 break;
 117         }
 118         case DEVICE_PATH_SUB_TYPE_MSG_MAC_ADDR: {
 119                 struct efi_device_path_mac_addr *mdp =
 120                         (struct efi_device_path_mac_addr *)dp;
 121
 122                 if (mdp->if_type != 0 && mdp->if_type != 1)
 123                         break;
 124
 125                 s += sprintf(s, "MAC(%02x%02x%02x%02x%02x%02x,0x%1x)",
 126                         mdp->mac.addr[0], mdp->mac.addr[1],
 127                         mdp->mac.addr[2], mdp->mac.addr[3],
 128                         mdp->mac.addr[4], mdp->mac.addr[5],
 129                         mdp->if_type);
 130
 131                 break;
 132         }
 133         case DEVICE_PATH_SUB_TYPE_MSG_USB_CLASS: {
 134                 struct efi_device_path_usb_class *ucdp =
 135                         (struct efi_device_path_usb_class *)dp;
 136
 137                 s += sprintf(s, "USBClass(%x,%x,%x,%x,%x)",
 138                         ucdp->vendor_id, ucdp->product_id,
 139                         ucdp->device_class, ucdp->device_subclass,
 140                         ucdp->device_protocol);
 141
 142                 break;
 143         }
 144         case DEVICE_PATH_SUB_TYPE_MSG_SD:
 145         case DEVICE_PATH_SUB_TYPE_MSG_MMC: {
 146                 const char *typename =
 147                         (dp->sub_type == DEVICE_PATH_SUB_TYPE_MSG_SD) ?
 148                                         "SD" : "eMMC";
 149                 struct efi_device_path_sd_mmc_path *sddp =
 150                         (struct efi_device_path_sd_mmc_path *)dp;
 151                 s += sprintf(s, "%s(%u)", typename, sddp->slot_number);
 152                 break;
 153         }
 154         default:
 155                 s = dp_unknown(s, dp);
 156                 break;
 157         }
 158         return s;
 159 }
 160
 161 /*
 162  * Convert a media device path node to text.
 163  *
 164  * @s           output buffer
 165  * @dp          device path node
 166  * @return      next unused buffer address
 167  */
 168 static char *dp_media(char *s, struct efi_device_path *dp)
 169 {
 170         switch (dp->sub_type) {
 171         case DEVICE_PATH_SUB_TYPE_HARD_DRIVE_PATH: {
 172                 struct efi_device_path_hard_drive_path *hddp =
 173                         (struct efi_device_path_hard_drive_path *)dp;
 174                 void *sig = hddp->partition_signature;
 175                 u64 start;
 176                 u64 end;
 177
 178                 /* Copy from packed structure to aligned memory */
 179                 memcpy(&start, &hddp->partition_start, sizeof(start));
 180                 memcpy(&end, &hddp->partition_end, sizeof(end));
 181
 182                 switch (hddp->signature_type) {
 183                 case SIG_TYPE_MBR: {
 184                         u32 signature;
 185
 186                         memcpy(&signature, sig, sizeof(signature));
 187                         s += sprintf(
 188                                 s, "HD(%d,MBR,0x%08x,0x%llx,0x%llx)",
 189                                 hddp->partition_number, signature, start, end);
 190                         break;
 191                         }
 192                 case SIG_TYPE_GUID:
 193                         s += sprintf(
 194                                 s, "HD(%d,GPT,%pUl,0x%llx,0x%llx)",
 195                                 hddp->partition_number, sig, start, end);
 196                         break;
 197                 default:
 198                         s += sprintf(
 199                                 s, "HD(%d,0x%02x,0,0x%llx,0x%llx)",
 200                                 hddp->partition_number, hddp->partmap_type,
 201                                 start, end);
 202                         break;
 203                 }
 204
 205                 break;
 206         }
 207         case DEVICE_PATH_SUB_TYPE_CDROM_PATH: {
 208                 struct efi_device_path_cdrom_path *cddp =
 209                         (struct efi_device_path_cdrom_path *)dp;
 210                 s += sprintf(s, "CDROM(0x%x)", cddp->boot_entry);
 211                 break;
 212         }
 213         case DEVICE_PATH_SUB_TYPE_FILE_PATH: {
 214                 struct efi_device_path_file_path *fp =
 215                         (struct efi_device_path_file_path *)dp;
 216                 int slen = (dp->length - sizeof(*dp)) / 2;
 217                 if (slen > MAX_NODE_LEN - 2)
 218                         slen = MAX_NODE_LEN - 2;
 219                 s += sprintf(s, "%-.*ls", slen, fp->str);
 220                 break;
 221         }
 222         default:
 223                 s = dp_unknown(s, dp);
 224                 break;
 225         }
 226         return s;
 227 }
 228
 229 /*
 230  * Converts a single node to a char string.
 231  *
 232  * @buffer              output buffer
 233  * @dp                  device path or node
 234  * @return              end of string
 235  */
 236 static char *efi_convert_single_device_node_to_text(
 237                 char *buffer,
 238                 struct efi_device_path *dp)
 239 {
 240         char *str = buffer;
 241
 242         switch (dp->type) {
 243         case DEVICE_PATH_TYPE_HARDWARE_DEVICE:
 244                 str = dp_hardware(str, dp);
 245                 break;
 246         case DEVICE_PATH_TYPE_ACPI_DEVICE:
 247                 str = dp_acpi(str, dp);
 248                 break;
 249         case DEVICE_PATH_TYPE_MESSAGING_DEVICE:
 250                 str = dp_msging(str, dp);
 251                 break;
 252         case DEVICE_PATH_TYPE_MEDIA_DEVICE:
 253                 str = dp_media(str, dp);
 254                 break;
 255         case DEVICE_PATH_TYPE_END:
 256                 break;
 257         default:
 258                 str = dp_unknown(str, dp);
 259         }
 260
 261         *str = '\0';
 262         return str;
 263 }
 264
 265 /*
 266  * This function implements the ConvertDeviceNodeToText service of the
 267  * EFI_DEVICE_PATH_TO_TEXT_PROTOCOL.
 268  * See the Unified Extensible Firmware Interface (UEFI) specification
 269  * for details.
 270  *
 271  * device_node          device node to be converted
 272  * display_only         true if the shorter text represenation shall be used
 273  * allow_shortcuts      true if shortcut forms may be used
 274  * @return              text represenation of the device path
 275  *                      NULL if out of memory of device_path is NULL
 276  */
 277 static uint16_t EFIAPI *efi_convert_device_node_to_text(
 278                 struct efi_device_path *device_node,
 279                 bool display_only,
 280                 bool allow_shortcuts)
 281 {
 282         char str[MAX_NODE_LEN];
 283         uint16_t *text = NULL;
 284
 285         EFI_ENTRY("%p, %d, %d", device_node, display_only, allow_shortcuts);
 286
 287         if (!device_node)
 288                 goto out;
 289         efi_convert_single_device_node_to_text(str, device_node);
 290
 291         text = efi_str_to_u16(str);
 292
 293 out:
 294         EFI_EXIT(EFI_SUCCESS);
 295         return text;
 296 }
 297
 298 /*
 299  * This function implements the ConvertDevicePathToText service of the
 300  * EFI_DEVICE_PATH_TO_TEXT_PROTOCOL.
 301  * See the Unified Extensible Firmware Interface (UEFI) specification
 302  * for details.
 303  *
 304  * device_path          device path to be converted
 305  * display_only         true if the shorter text represenation shall be used
 306  * allow_shortcuts      true if shortcut forms may be used
 307  * @return              text represenation of the device path
 308  *                      NULL if out of memory of device_path is NULL
 309  */
 310 static uint16_t EFIAPI *efi_convert_device_path_to_text(
 311                 struct efi_device_path *device_path,
 312                 bool display_only,
 313                 bool allow_shortcuts)
 314 {
 315         uint16_t *text = NULL;
 316         char buffer[MAX_PATH_LEN];
 317         char *str = buffer;
 318
 319         EFI_ENTRY("%p, %d, %d", device_path, display_only, allow_shortcuts);
 320
 321         if (!device_path)
 322                 goto out;
 323         while (device_path &&
 324                str + MAX_NODE_LEN < buffer + MAX_PATH_LEN) {
 325                 *str++ = '/';
 326                 str = efi_convert_single_device_node_to_text(str, device_path);
 327                 device_path = efi_dp_next(device_path);
 328         }
 329
 330         text = efi_str_to_u16(buffer);
 331
 332 out:
 333         EFI_EXIT(EFI_SUCCESS);
 334         return text;
 335 }
 336
 337 /* helper for debug prints.. efi_free_pool() the result. */
 338 uint16_t *efi_dp_str(struct efi_device_path *dp)
 339 {
 340         return EFI_CALL(efi_convert_device_path_to_text(dp, true, true));
 341 }
 342
 343 const struct efi_device_path_to_text_protocol efi_device_path_to_text = {
 344         .convert_device_node_to_text = efi_convert_device_node_to_text,
 345         .convert_device_path_to_text = efi_convert_device_path_to_text,
 346 };