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