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                                         "SDCard" : "MMC";
 128                 struct efi_device_path_sd_mmc_path *sddp =
 129                         (struct efi_device_path_sd_mmc_path *)dp;
 130                 s += sprintf(s, "%s(Slot%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 static char *dp_media(char *s, struct efi_device_path *dp)
 141 {
 142         switch (dp->sub_type) {
 143         case DEVICE_PATH_SUB_TYPE_HARD_DRIVE_PATH: {
 144                 struct efi_device_path_hard_drive_path *hddp =
 145                         (struct efi_device_path_hard_drive_path *)dp;
 146                 void *sig = hddp->partition_signature;
 147
 148                 switch (hddp->signature_type) {
 149                 case SIG_TYPE_MBR:
 150                         s += sprintf(s, "HD(Part%d,Sig%08x)",
 151                                      hddp->partition_number,
 152                                      *(uint32_t *)sig);
 153                         break;
 154                 case SIG_TYPE_GUID:
 155                         s += sprintf(s, "HD(Part%d,Sig%pUl)",
 156                                      hddp->partition_number, sig);
 157                         break;
 158                 default:
 159                         s += sprintf(s, "HD(Part%d,MBRType=%02x,SigType=%02x)",
 160                                      hddp->partition_number, hddp->partmap_type,
 161                                      hddp->signature_type);
 162                         break;
 163                 }
 164
 165                 break;
 166         }
 167         case DEVICE_PATH_SUB_TYPE_CDROM_PATH: {
 168                 struct efi_device_path_cdrom_path *cddp =
 169                         (struct efi_device_path_cdrom_path *)dp;
 170                 s += sprintf(s, "CDROM(0x%x)", cddp->boot_entry);
 171                 break;
 172         }
 173         case DEVICE_PATH_SUB_TYPE_FILE_PATH: {
 174                 struct efi_device_path_file_path *fp =
 175                         (struct efi_device_path_file_path *)dp;
 176                 int slen = (dp->length - sizeof(*dp)) / 2;
 177                 if (slen > MAX_NODE_LEN - 2)
 178                         slen = MAX_NODE_LEN - 2;
 179                 s += sprintf(s, "%-.*ls", slen, fp->str);
 180                 break;
 181         }
 182         default:
 183                 s = dp_unknown(s, dp);
 184                 break;
 185         }
 186         return s;
 187 }
 188
 189 /*
 190  * Converts a single node to a char string.
 191  *
 192  * @buffer              output buffer
 193  * @dp                  device path or node
 194  * @return              end of string
 195  */
 196 static char *efi_convert_single_device_node_to_text(
 197                 char *buffer,
 198                 struct efi_device_path *dp)
 199 {
 200         char *str = buffer;
 201
 202         switch (dp->type) {
 203         case DEVICE_PATH_TYPE_HARDWARE_DEVICE:
 204                 str = dp_hardware(str, dp);
 205                 break;
 206         case DEVICE_PATH_TYPE_ACPI_DEVICE:
 207                 str = dp_acpi(str, dp);
 208                 break;
 209         case DEVICE_PATH_TYPE_MESSAGING_DEVICE:
 210                 str = dp_msging(str, dp);
 211                 break;
 212         case DEVICE_PATH_TYPE_MEDIA_DEVICE:
 213                 str = dp_media(str, dp);
 214                 break;
 215         default:
 216                 str = dp_unknown(str, dp);
 217         }
 218
 219         *str = '\0';
 220         return str;
 221 }
 222
 223 /*
 224  * This function implements the ConvertDeviceNodeToText service of the
 225  * EFI_DEVICE_PATH_TO_TEXT_PROTOCOL.
 226  * See the Unified Extensible Firmware Interface (UEFI) specification
 227  * for details.
 228  *
 229  * device_node          device node to be converted
 230  * display_only         true if the shorter text represenation shall be used
 231  * allow_shortcuts      true if shortcut forms may be used
 232  * @return              text represenation of the device path
 233  *                      NULL if out of memory of device_path is NULL
 234  */
 235 static uint16_t EFIAPI *efi_convert_device_node_to_text(
 236                 struct efi_device_path *device_node,
 237                 bool display_only,
 238                 bool allow_shortcuts)
 239 {
 240         char str[MAX_NODE_LEN];
 241         uint16_t *text = NULL;
 242
 243         EFI_ENTRY("%p, %d, %d", device_node, display_only, allow_shortcuts);
 244
 245         if (!device_node)
 246                 goto out;
 247         efi_convert_single_device_node_to_text(str, device_node);
 248
 249         text = efi_str_to_u16(str);
 250
 251 out:
 252         EFI_EXIT(EFI_SUCCESS);
 253         return text;
 254 }
 255
 256 /*
 257  * This function implements the ConvertDevicePathToText 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_path          device path 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_path_to_text(
 269                 struct efi_device_path *device_path,
 270                 bool display_only,
 271                 bool allow_shortcuts)
 272 {
 273         uint16_t *text = NULL;
 274         char buffer[MAX_PATH_LEN];
 275         char *str = buffer;
 276
 277         EFI_ENTRY("%p, %d, %d", device_path, display_only, allow_shortcuts);
 278
 279         if (!device_path)
 280                 goto out;
 281         while (device_path &&
 282                str + MAX_NODE_LEN < buffer + MAX_PATH_LEN) {
 283                 *str++ = '/';
 284                 str = efi_convert_single_device_node_to_text(str, device_path);
 285                 device_path = efi_dp_next(device_path);
 286         }
 287
 288         text = efi_str_to_u16(buffer);
 289
 290 out:
 291         EFI_EXIT(EFI_SUCCESS);
 292         return text;
 293 }
 294
 295 /* helper for debug prints.. efi_free_pool() the result. */
 296 uint16_t *efi_dp_str(struct efi_device_path *dp)
 297 {
 298         return EFI_CALL(efi_convert_device_path_to_text(dp, true, true));
 299 }
 300
 301 const struct efi_device_path_to_text_protocol efi_device_path_to_text = {
 302         .convert_device_node_to_text = efi_convert_device_node_to_text,
 303         .convert_device_path_to_text = efi_convert_device_path_to_text,
 304 };