lib/efi_loader/efi_device_path_to_text.c

   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         default:
 249                 str = dp_unknown(str, dp);
 250         }
 251
 252         *str = '\0';
 253         return str;
 254 }
 255
 256 /*
 257  * This function implements the ConvertDeviceNodeToText service of the
 258  * EFI_DEVICE_PATH_TO_TEXT_PROTOCOL.
 259  * See the Unified Extensible Firmware Interface (UEFI) specification
 260  * for details.
 261  *
 262  * device_node          device node to be converted
 263  * display_only         true if the shorter text represenation shall be used
 264  * allow_shortcuts      true if shortcut forms may be used
 265  * @return              text represenation of the device path
 266  *                      NULL if out of memory of device_path is NULL
 267  */
 268 static uint16_t EFIAPI *efi_convert_device_node_to_text(
 269                 struct efi_device_path *device_node,
 270                 bool display_only,
 271                 bool allow_shortcuts)
 272 {
 273         char str[MAX_NODE_LEN];
 274         uint16_t *text = NULL;
 275
 276         EFI_ENTRY("%p, %d, %d", device_node, display_only, allow_shortcuts);
 277
 278         if (!device_node)
 279                 goto out;
 280         efi_convert_single_device_node_to_text(str, device_node);
 281
 282         text = efi_str_to_u16(str);
 283
 284 out:
 285         EFI_EXIT(EFI_SUCCESS);
 286         return text;
 287 }
 288
 289 /*
 290  * This function implements the ConvertDevicePathToText service of the
 291  * EFI_DEVICE_PATH_TO_TEXT_PROTOCOL.
 292  * See the Unified Extensible Firmware Interface (UEFI) specification
 293  * for details.
 294  *
 295  * device_path          device path to be converted
 296  * display_only         true if the shorter text represenation shall be used
 297  * allow_shortcuts      true if shortcut forms may be used
 298  * @return              text represenation of the device path
 299  *                      NULL if out of memory of device_path is NULL
 300  */
 301 static uint16_t EFIAPI *efi_convert_device_path_to_text(
 302                 struct efi_device_path *device_path,
 303                 bool display_only,
 304                 bool allow_shortcuts)
 305 {
 306         uint16_t *text = NULL;
 307         char buffer[MAX_PATH_LEN];
 308         char *str = buffer;
 309
 310         EFI_ENTRY("%p, %d, %d", device_path, display_only, allow_shortcuts);
 311
 312         if (!device_path)
 313                 goto out;
 314         while (device_path &&
 315                str + MAX_NODE_LEN < buffer + MAX_PATH_LEN) {
 316                 *str++ = '/';
 317                 str = efi_convert_single_device_node_to_text(str, device_path);
 318                 device_path = efi_dp_next(device_path);
 319         }
 320
 321         text = efi_str_to_u16(buffer);
 322
 323 out:
 324         EFI_EXIT(EFI_SUCCESS);
 325         return text;
 326 }
 327
 328 /* helper for debug prints.. efi_free_pool() the result. */
 329 uint16_t *efi_dp_str(struct efi_device_path *dp)
 330 {
 331         return EFI_CALL(efi_convert_device_path_to_text(dp, true, true));
 332 }
 333
 334 const struct efi_device_path_to_text_protocol efi_device_path_to_text = {
 335         .convert_device_node_to_text = efi_convert_device_node_to_text,
 336         .convert_device_path_to_text = efi_convert_device_path_to_text,
 337 };