src/shared/dissect-image.h

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 #pragma once
   3
   4 #include <stdbool.h>
   5
   6 #include "sd-id128.h"
   7
   8 #include "macro.h"
   9
  10 typedef struct DissectedImage DissectedImage;
  11 typedef struct DissectedPartition DissectedPartition;
  12 typedef struct DecryptedImage DecryptedImage;
  13
  14 struct DissectedPartition {
  15         bool found:1;
  16         bool rw:1;
  17         int partno;        /* -1 if there was no partition and the images contains a file system directly */
  18         int architecture;  /* Intended architecture: either native, secondary or unset (-1). */
  19         sd_id128_t uuid;   /* Partition entry UUID as reported by the GPT */
  20         char *fstype;
  21         char *node;
  22         char *decrypted_node;
  23         char *decrypted_fstype;
  24 };
  25
  26 enum  {
  27         PARTITION_ROOT,
  28         PARTITION_ROOT_SECONDARY,  /* Secondary architecture */
  29         PARTITION_HOME,
  30         PARTITION_SRV,
  31         PARTITION_ESP,
  32         PARTITION_XBOOTLDR,
  33         PARTITION_SWAP,
  34         PARTITION_ROOT_VERITY, /* verity data for the PARTITION_ROOT partition */
  35         PARTITION_ROOT_SECONDARY_VERITY, /* verity data for the PARTITION_ROOT_SECONDARY partition */
  36         PARTITION_TMP,
  37         PARTITION_VAR,
  38         _PARTITION_DESIGNATOR_MAX,
  39         _PARTITION_DESIGNATOR_INVALID = -1
  40 };
  41
  42 static inline int PARTITION_VERITY_OF(int p) {
  43         if (p == PARTITION_ROOT)
  44                 return PARTITION_ROOT_VERITY;
  45         if (p == PARTITION_ROOT_SECONDARY)
  46                 return PARTITION_ROOT_SECONDARY_VERITY;
  47         return _PARTITION_DESIGNATOR_INVALID;
  48 }
  49
  50 typedef enum DissectImageFlags {
  51         DISSECT_IMAGE_READ_ONLY           = 1 << 0,
  52         DISSECT_IMAGE_DISCARD_ON_LOOP     = 1 << 1,  /* Turn on "discard" if on a loop device and file system supports it */
  53         DISSECT_IMAGE_DISCARD             = 1 << 2,  /* Turn on "discard" if file system supports it, on all block devices */
  54         DISSECT_IMAGE_DISCARD_ON_CRYPTO   = 1 << 3,  /* Turn on "discard" also on crypto devices */
  55         DISSECT_IMAGE_DISCARD_ANY = DISSECT_IMAGE_DISCARD_ON_LOOP |
  56                                     DISSECT_IMAGE_DISCARD |
  57                                     DISSECT_IMAGE_DISCARD_ON_CRYPTO,
  58         DISSECT_IMAGE_GPT_ONLY            = 1 << 4,  /* Only recognize images with GPT partition tables */
  59         DISSECT_IMAGE_REQUIRE_ROOT        = 1 << 5,  /* Don't accept disks without root partition */
  60         DISSECT_IMAGE_MOUNT_ROOT_ONLY     = 1 << 6,  /* Mount only the root partition */
  61         DISSECT_IMAGE_MOUNT_NON_ROOT_ONLY = 1 << 7,  /* Mount only non-root partitions */
  62         DISSECT_IMAGE_VALIDATE_OS         = 1 << 8,  /* Refuse mounting images that aren't identifiable as OS images */
  63         DISSECT_IMAGE_NO_UDEV             = 1 << 9,  /* Don't wait for udev initializing things */
  64         DISSECT_IMAGE_RELAX_VAR_CHECK     = 1 << 10, /* Don't insist that the UUID of /var is hashed from /etc/machine-id */
  65         DISSECT_IMAGE_FSCK                = 1 << 11, /* File system check the partition before mounting (no effect when combined with DISSECT_IMAGE_READ_ONLY) */
  66         DISSECT_IMAGE_NO_PARTITION_TABLE  = 1 << 12, /* Only recognize single file system images */
  67 } DissectImageFlags;
  68
  69 struct DissectedImage {
  70         bool encrypted:1;
  71         bool verity:1;     /* verity available and usable */
  72         bool can_verity:1; /* verity available, but not necessarily used */
  73         bool single_file_system:1; /* MBR/GPT or single file system */
  74
  75         DissectedPartition partitions[_PARTITION_DESIGNATOR_MAX];
  76
  77         char *hostname;
  78         sd_id128_t machine_id;
  79         char **machine_info;
  80         char **os_release;
  81 };
  82
  83 int probe_filesystem(const char *node, char **ret_fstype);
  84 int dissect_image(int fd, const void *root_hash, size_t root_hash_size, const char *verity_data, DissectImageFlags flags, DissectedImage **ret);
  85 int dissect_image_and_warn(int fd, const char *name, const void *root_hash, size_t root_hash_size, const char *verity_data, DissectImageFlags flags, DissectedImage **ret);
  86
  87 DissectedImage* dissected_image_unref(DissectedImage *m);
  88 DEFINE_TRIVIAL_CLEANUP_FUNC(DissectedImage*, dissected_image_unref);
  89
  90 int dissected_image_decrypt(DissectedImage *m, const char *passphrase, const void *root_hash, size_t root_hash_size, const char *verity_data, DissectImageFlags flags, DecryptedImage **ret);
  91 int dissected_image_decrypt_interactively(DissectedImage *m, const char *passphrase, const void *root_hash, size_t root_hash_size, const char *verity_data, DissectImageFlags flags, DecryptedImage **ret);
  92 int dissected_image_mount(DissectedImage *m, const char *dest, uid_t uid_shift, DissectImageFlags flags);
  93
  94 int dissected_image_acquire_metadata(DissectedImage *m);
  95
  96 DecryptedImage* decrypted_image_unref(DecryptedImage *p);
  97 DEFINE_TRIVIAL_CLEANUP_FUNC(DecryptedImage*, decrypted_image_unref);
  98 int decrypted_image_relinquish(DecryptedImage *d);
  99
 100 const char* partition_designator_to_string(int i) _const_;
 101 int partition_designator_from_string(const char *name) _pure_;
 102
 103 int verity_metadata_load(const char *image, void **ret_roothash, size_t *ret_roothash_size, char **ret_verity_data);
 104 bool dissected_image_can_do_verity(const DissectedImage *image, unsigned partition_designator);
 105 bool dissected_image_has_verity(const DissectedImage *image, unsigned partition_designator);