From f17a54035876808331c7ab753a0706de4bf46a7a Mon Sep 17 00:00:00 2001 From: John Lane Date: Tue, 23 Jun 2015 11:16:30 +0100 Subject: [PATCH v6 5/6] cryptodisk: enable the backends to implement key files Signed-off-by: John Lane GNUtoo@cyberdimension.org: rebase, patch split, small fixes, commit message Signed-off-by: Denis 'GNUtoo' Carikli Reviewed-by: Patrick Steinhardt --- grub-core/disk/cryptodisk.c | 87 ++++++++++++++++++++++++++++++++++++- grub-core/disk/geli.c | 7 +-- grub-core/disk/luks.c | 7 ++- grub-core/disk/luks2.c | 7 +-- include/grub/cryptodisk.h | 5 ++- include/grub/file.h | 2 + 6 files changed, 106 insertions(+), 9 deletions(-) diff --git a/grub-core/disk/cryptodisk.c b/grub-core/disk/cryptodisk.c index 6ad2e486e..dd94736d3 100644 --- a/grub-core/disk/cryptodisk.c +++ b/grub-core/disk/cryptodisk.c @@ -42,6 +42,9 @@ static const struct grub_arg_option options[] = {"all", 'a', 0, N_("Mount all."), 0, 0}, {"boot", 'b', 0, N_("Mount all volumes with `boot' flag set."), 0, 0}, {"header", 'H', 0, N_("Read header from file"), 0, ARG_TYPE_STRING}, + {"keyfile", 'k', 0, N_("Key file"), 0, ARG_TYPE_STRING}, + {"keyfile-offset", 'O', 0, N_("Key file offset (bytes)"), 0, ARG_TYPE_INT}, + {"keyfile-size", 'S', 0, N_("Key file data size (bytes)"), 0, ARG_TYPE_INT}, {0, 0, 0, 0, 0, 0} }; @@ -972,6 +975,8 @@ grub_util_cryptodisk_get_uuid (grub_disk_t disk) static int check_boot, have_it; static char *search_uuid; static grub_file_t hdr; +static grub_uint8_t *key, keyfile_buffer[GRUB_CRYPTODISK_MAX_KEYFILE_SIZE]; +static grub_ssize_t key_size; static void cryptodisk_close (grub_cryptodisk_t dev) @@ -1002,7 +1007,7 @@ grub_cryptodisk_scan_device_real (const char *name, grub_disk_t source) if (!dev) continue; - err = cr->recover_key (source, dev, hdr); + err = cr->recover_key (source, dev, hdr, key, key_size); if (err) { cryptodisk_close (dev); @@ -1112,6 +1117,86 @@ grub_cmd_cryptomount (grub_extcmd_context_t ctxt, int argc, char **args) hdr = NULL; have_it = 0; + key = NULL; + + if (state[4].set) /* keyfile */ + { + const char *p = NULL; + grub_file_t keyfile; + int keyfile_offset; + grub_size_t requested_keyfile_size = 0; + + + if (state[5].set) /* keyfile-offset */ + { + keyfile_offset = grub_strtoul (state[5].arg, &p, 0); + + if (grub_errno != GRUB_ERR_NONE) + return grub_errno; + + if (*p != '\0') + return grub_error (GRUB_ERR_BAD_ARGUMENT, + N_("unrecognized number")); + } + else + { + keyfile_offset = 0; + } + + if (state[6].set) /* keyfile-size */ + { + requested_keyfile_size = grub_strtoul (state[6].arg, &p, 0); + + if (*p != '\0') + return grub_error (GRUB_ERR_BAD_ARGUMENT, + N_("unrecognized number")); + + if (grub_errno != GRUB_ERR_NONE) + return grub_errno; + + if (requested_keyfile_size > GRUB_CRYPTODISK_MAX_KEYFILE_SIZE) + return grub_error (GRUB_ERR_OUT_OF_RANGE, + N_("Key file size exceeds maximum (%" + PRIuGRUB_SIZE ")\n"), + GRUB_CRYPTODISK_MAX_KEYFILE_SIZE); + + if (requested_keyfile_size == 0) + return grub_error (GRUB_ERR_OUT_OF_RANGE, + N_("Key file size is 0\n")); + } + + keyfile = grub_file_open (state[4].arg, + GRUB_FILE_TYPE_CRYPTODISK_ENCRYPTION_KEY); + if (!keyfile) + return grub_errno; + + if (grub_file_seek (keyfile, keyfile_offset) == (grub_off_t)-1) + return grub_errno; + + if (requested_keyfile_size) + { + if (requested_keyfile_size > (keyfile->size - keyfile_offset)) + return grub_error (GRUB_ERR_FILE_READ_ERROR, + N_("Keyfile is too small: " + "requested %" PRIuGRUB_SIZE " bytes, " + "but the file only has %" PRIuGRUB_SIZE + " bytes.\n"), + requested_keyfile_size, + keyfile->size); + + key_size = requested_keyfile_size; + } + else + { + key_size = keyfile->size - keyfile_offset; + } + + if (grub_file_read (keyfile, keyfile_buffer, key_size) != key_size) + return grub_error (GRUB_ERR_FILE_READ_ERROR, + (N_("Error reading key file\n"))); + key = keyfile_buffer; + } + if (state[0].set) { grub_cryptodisk_t dev; diff --git a/grub-core/disk/geli.c b/grub-core/disk/geli.c index acd09d874..159ac0f96 100644 --- a/grub-core/disk/geli.c +++ b/grub-core/disk/geli.c @@ -404,7 +404,8 @@ geli_scan (grub_disk_t disk, const char *check_uuid, int boot_only, } static grub_err_t -geli_recover_key (grub_disk_t source, grub_cryptodisk_t dev, grub_file_t hdr) +geli_recover_key (grub_disk_t source, grub_cryptodisk_t dev, grub_file_t hdr, + grub_uint8_t *key, grub_size_t keyfile_size) { grub_size_t keysize; grub_uint8_t digest[GRUB_CRYPTO_MAX_MDLEN]; @@ -420,8 +421,8 @@ geli_recover_key (grub_disk_t source, grub_cryptodisk_t dev, grub_file_t hdr) grub_disk_addr_t sector; grub_err_t err; - /* Detached headers are not implemented yet */ - if (hdr) + /* Detached headers and keyfiles are not implemented yet */ + if (hdr || key || keyfile_size) return GRUB_ERR_NOT_IMPLEMENTED_YET; if (dev->cipher->cipher->blocksize > GRUB_CRYPTO_MAX_CIPHER_BLOCKSIZE) diff --git a/grub-core/disk/luks.c b/grub-core/disk/luks.c index 6286302e7..0dd33b2af 100644 --- a/grub-core/disk/luks.c +++ b/grub-core/disk/luks.c @@ -161,7 +161,8 @@ luks_scan (grub_disk_t disk, const char *check_uuid, int check_boot, } static grub_err_t -luks_recover_key (grub_disk_t source, grub_cryptodisk_t dev, grub_file_t hdr) +luks_recover_key (grub_disk_t source, grub_cryptodisk_t dev, grub_file_t hdr, + grub_uint8_t *keyfile_bytes, grub_size_t keyfile_bytes_size) { struct grub_luks_phdr header; grub_size_t keysize; @@ -175,6 +176,10 @@ luks_recover_key (grub_disk_t source, grub_cryptodisk_t dev, grub_file_t hdr) char *tmp; grub_uint32_t sector; + /* Keyfiles are not implemented yet */ + if (keyfile_bytes || keyfile_bytes_size) + return GRUB_ERR_NOT_IMPLEMENTED_YET; + if (hdr) { if (grub_file_seek (hdr, 0) == (grub_off_t) -1) diff --git a/grub-core/disk/luks2.c b/grub-core/disk/luks2.c index bc00e8bbc..6a38a1f4d 100644 --- a/grub-core/disk/luks2.c +++ b/grub-core/disk/luks2.c @@ -529,7 +529,8 @@ luks2_decrypt_key (grub_uint8_t *out_key, static grub_err_t luks2_recover_key (grub_disk_t disk, grub_cryptodisk_t crypt, - grub_file_t hdr_file) + grub_file_t hdr_file, grub_uint8_t *key, + grub_size_t keyfile_size) { grub_uint8_t candidate_key[GRUB_CRYPTODISK_MAX_KEYLEN]; char passphrase[MAX_PASSPHRASE], cipher[32]; @@ -543,8 +544,8 @@ luks2_recover_key (grub_disk_t disk, grub_cryptodisk_t crypt, grub_json_t *json = NULL, keyslots; grub_err_t ret; - /* Detached headers are not implemented yet */ - if (hdr_file) + /* Detached headers and keyfiles are not implemented yet */ + if (hdr_file || key || keyfile_size) return GRUB_ERR_NOT_IMPLEMENTED_YET; ret = luks2_read_header (disk, &header); diff --git a/include/grub/cryptodisk.h b/include/grub/cryptodisk.h index e24b1b8cb..6d2610f93 100644 --- a/include/grub/cryptodisk.h +++ b/include/grub/cryptodisk.h @@ -55,6 +55,8 @@ typedef enum #define GRUB_CRYPTODISK_GF_BYTES (1U << GRUB_CRYPTODISK_GF_LOG_BYTES) #define GRUB_CRYPTODISK_MAX_KEYLEN 128 +#define GRUB_CRYPTODISK_MAX_KEYFILE_SIZE 8192 + struct grub_cryptodisk; typedef gcry_err_code_t @@ -110,7 +112,8 @@ struct grub_cryptodisk_dev grub_cryptodisk_t (*scan) (grub_disk_t disk, const char *check_uuid, int boot_only, grub_file_t hdr); grub_err_t (*recover_key) (grub_disk_t disk, grub_cryptodisk_t dev, - grub_file_t hdr); + grub_file_t hdr, grub_uint8_t *key, + grub_size_t keyfile_size); }; typedef struct grub_cryptodisk_dev *grub_cryptodisk_dev_t; diff --git a/include/grub/file.h b/include/grub/file.h index a7d7be853..97678aa45 100644 --- a/include/grub/file.h +++ b/include/grub/file.h @@ -92,6 +92,8 @@ enum grub_file_type GRUB_FILE_TYPE_ZFS_ENCRYPTION_KEY, /* File holiding the encryption metadata header */ GRUB_FILE_TYPE_CRYPTODISK_DETACHED_HEADER, + /* File holiding the encryption key */ + GRUB_FILE_TYPE_CRYPTODISK_ENCRYPTION_KEY, /* File we open n grub-fstest. */ GRUB_FILE_TYPE_FSTEST, /* File we open n grub-mount. */ -- 2.28.0