diff options
Diffstat (limited to '0003-Cryptomount-luks-allow-multiple-passphrase-attempts.patch')
| -rw-r--r-- | 0003-Cryptomount-luks-allow-multiple-passphrase-attempts.patch | 317 |
1 files changed, 317 insertions, 0 deletions
diff --git a/0003-Cryptomount-luks-allow-multiple-passphrase-attempts.patch b/0003-Cryptomount-luks-allow-multiple-passphrase-attempts.patch new file mode 100644 index 000000000000..07239e95f43d --- /dev/null +++ b/0003-Cryptomount-luks-allow-multiple-passphrase-attempts.patch @@ -0,0 +1,317 @@ +From f42b774020839b1e07c5fa0ad7be4735d35cc705 Mon Sep 17 00:00:00 2001 +From: Maxim Fomin <maxim@fomin.one> +Date: Fri, 8 Jan 2021 20:00:31 +0000 +Subject: [PATCH] Support for multiple LUKS passphrase attempts + +--- + grub-core/disk/luks.c | 273 ++++++++++++++++++++++-------------------- + 1 file changed, 141 insertions(+), 132 deletions(-) + +diff --git a/grub-core/disk/luks.c b/grub-core/disk/luks.c +index eea85338d..3f98df287 100644 +--- a/grub-core/disk/luks.c ++++ b/grub-core/disk/luks.c +@@ -34,6 +34,8 @@ GRUB_MOD_LICENSE ("GPLv3+"); + + #define LUKS_KEY_ENABLED 0x00AC71F3 + ++#define LUKS_PASSPHRASE_ATTEMPTS 3 ++ + /* On disk LUKS header */ + struct grub_luks_phdr + { +@@ -182,6 +184,7 @@ luks_recover_key (grub_disk_t source, + grub_size_t max_stripes = 1; + char *tmp; + grub_uint32_t sector; ++ unsigned int attempts = LUKS_PASSPHRASE_ATTEMPTS; + + err = GRUB_ERR_NONE; + +@@ -211,145 +214,151 @@ luks_recover_key (grub_disk_t source, + if (!split_key) + return grub_errno; + +- if (keyfile_bytes) +- { +- /* Use bytestring from key file as passphrase */ +- passphrase = keyfile_bytes; +- passphrase_length = keyfile_bytes_size; +- } +- else ++ while (attempts) + { +- /* Get the passphrase from the user. */ +- tmp = NULL; +- if (source->partition) +- tmp = grub_partition_get_name (source->partition); +- grub_printf_ (N_("Enter passphrase for %s%s%s (%s): "), source->name, +- source->partition ? "," : "", tmp ? : "", dev->uuid); +- grub_free (tmp); +- if (!grub_password_get (interactive_passphrase, MAX_PASSPHRASE)) ++ if (keyfile_bytes) + { +- grub_free (split_key); +- return grub_error (GRUB_ERR_BAD_ARGUMENT, "Passphrase not supplied"); ++ /* Use bytestring from key file as passphrase */ ++ passphrase = keyfile_bytes; ++ passphrase_length = keyfile_bytes_size; ++ keyfile_bytes = NULL; /* use it only once */ ++ } ++ else ++ { ++ /* Get the passphrase from the user. */ ++ tmp = NULL; ++ if (source->partition) ++ tmp = grub_partition_get_name (source->partition); ++ grub_printf_ (N_("Enter passphrase for %s%s%s (%s): "), source->name, ++ source->partition ? "," : "", tmp ? : "", dev->uuid); ++ grub_free (tmp); ++ if (!grub_password_get (interactive_passphrase, MAX_PASSPHRASE)) ++ { ++ grub_free (split_key); ++ return grub_error (GRUB_ERR_BAD_ARGUMENT, "Passphrase not supplied"); ++ } ++ ++ passphrase = (grub_uint8_t *)interactive_passphrase; ++ passphrase_length = grub_strlen (interactive_passphrase); + } + +- passphrase = (grub_uint8_t *)interactive_passphrase; +- passphrase_length = grub_strlen (interactive_passphrase); ++ /* Try to recover master key from each active keyslot. */ ++ for (i = 0; i < ARRAY_SIZE (header.keyblock); i++) ++ { ++ gcry_err_code_t gcry_err; ++ grub_uint8_t candidate_key[GRUB_CRYPTODISK_MAX_KEYLEN]; ++ grub_uint8_t digest[GRUB_CRYPTODISK_MAX_KEYLEN]; ++ ++ /* Check if keyslot is enabled. */ ++ if (grub_be_to_cpu32 (header.keyblock[i].active) != LUKS_KEY_ENABLED) ++ continue; ++ ++ grub_dprintf ("luks", "Trying keyslot %d\n", i); ++ ++ /* Calculate the PBKDF2 of the user supplied passphrase. */ ++ gcry_err = grub_crypto_pbkdf2 (dev->hash, (grub_uint8_t *) passphrase, ++ passphrase_length, ++ header.keyblock[i].passwordSalt, ++ sizeof (header.keyblock[i].passwordSalt), ++ grub_be_to_cpu32 (header.keyblock[i]. ++ passwordIterations), ++ digest, keysize); ++ ++ if (gcry_err) ++ { ++ grub_free (split_key); ++ return grub_crypto_gcry_error (gcry_err); ++ } ++ ++ grub_dprintf ("luks", "PBKDF2 done\n"); ++ ++ gcry_err = grub_cryptodisk_setkey (dev, digest, keysize); ++ if (gcry_err) ++ { ++ grub_free (split_key); ++ return grub_crypto_gcry_error (gcry_err); ++ } ++ ++ sector = grub_be_to_cpu32 (header.keyblock[i].keyMaterialOffset); ++ length = (keysize * grub_be_to_cpu32 (header.keyblock[i].stripes)); ++ ++ /* Read and decrypt the key material from the disk. */ ++ if (hdr) ++ { ++ grub_file_seek (hdr, sector * 512); ++ if (grub_file_read (hdr, split_key, length) != (grub_ssize_t)length) ++ err = GRUB_ERR_READ_ERROR; ++ } ++ else ++ err = grub_disk_read (source, sector, 0, length, split_key); ++ if (err) ++ { ++ grub_free (split_key); ++ return err; ++ } ++ ++ gcry_err = grub_cryptodisk_decrypt (dev, split_key, length, 0, ++ GRUB_LUKS1_LOG_SECTOR_SIZE); ++ if (gcry_err) ++ { ++ grub_free (split_key); ++ return grub_crypto_gcry_error (gcry_err); ++ } ++ ++ /* Merge the decrypted key material to get the candidate master key. */ ++ gcry_err = AF_merge (dev->hash, split_key, candidate_key, keysize, ++ grub_be_to_cpu32 (header.keyblock[i].stripes)); ++ if (gcry_err) ++ { ++ grub_free (split_key); ++ return grub_crypto_gcry_error (gcry_err); ++ } ++ ++ grub_dprintf ("luks", "candidate key recovered\n"); ++ ++ /* Calculate the PBKDF2 of the candidate master key. */ ++ gcry_err = grub_crypto_pbkdf2 (dev->hash, candidate_key, ++ grub_be_to_cpu32 (header.keyBytes), ++ header.mkDigestSalt, ++ sizeof (header.mkDigestSalt), ++ grub_be_to_cpu32 ++ (header.mkDigestIterations), ++ candidate_digest, ++ sizeof (candidate_digest)); ++ if (gcry_err) ++ { ++ grub_free (split_key); ++ return grub_crypto_gcry_error (gcry_err); ++ } ++ ++ /* Compare the calculated PBKDF2 to the digest stored ++ in the header to see if it's correct. */ ++ if (grub_memcmp (candidate_digest, header.mkDigest, ++ sizeof (header.mkDigest)) != 0) ++ { ++ grub_dprintf ("luks", "bad digest\n"); ++ continue; ++ } ++ ++ /* TRANSLATORS: It's a cryptographic key slot: one element of an array ++ where each element is either empty or holds a key. */ ++ grub_printf_ (N_("Slot %d opened\n"), i); ++ ++ /* Set the master key. */ ++ gcry_err = grub_cryptodisk_setkey (dev, candidate_key, keysize); ++ if (gcry_err) ++ { ++ grub_free (split_key); ++ return grub_crypto_gcry_error (gcry_err); ++ } + +- } ++ grub_free (split_key); + +- /* Try to recover master key from each active keyslot. */ +- for (i = 0; i < ARRAY_SIZE (header.keyblock); i++) +- { +- gcry_err_code_t gcry_err; +- grub_uint8_t candidate_key[GRUB_CRYPTODISK_MAX_KEYLEN]; +- grub_uint8_t digest[GRUB_CRYPTODISK_MAX_KEYLEN]; +- +- /* Check if keyslot is enabled. */ +- if (grub_be_to_cpu32 (header.keyblock[i].active) != LUKS_KEY_ENABLED) +- continue; +- +- grub_dprintf ("luks", "Trying keyslot %d\n", i); +- +- /* Calculate the PBKDF2 of the user supplied passphrase. */ +- gcry_err = grub_crypto_pbkdf2 (dev->hash, (grub_uint8_t *) passphrase, +- passphrase_length, +- header.keyblock[i].passwordSalt, +- sizeof (header.keyblock[i].passwordSalt), +- grub_be_to_cpu32 (header.keyblock[i]. +- passwordIterations), +- digest, keysize); +- +- if (gcry_err) +- { +- grub_free (split_key); +- return grub_crypto_gcry_error (gcry_err); +- } +- +- grub_dprintf ("luks", "PBKDF2 done\n"); +- +- gcry_err = grub_cryptodisk_setkey (dev, digest, keysize); +- if (gcry_err) +- { +- grub_free (split_key); +- return grub_crypto_gcry_error (gcry_err); +- } +- +- sector = grub_be_to_cpu32 (header.keyblock[i].keyMaterialOffset); +- length = (keysize * grub_be_to_cpu32 (header.keyblock[i].stripes)); +- +- /* Read and decrypt the key material from the disk. */ +- if (hdr) +- { +- grub_file_seek (hdr, sector * 512); +- if (grub_file_read (hdr, split_key, length) != (grub_ssize_t)length) +- err = GRUB_ERR_READ_ERROR; ++ return GRUB_ERR_NONE; + } +- else +- err = grub_disk_read (source, sector, 0, length, split_key); +- if (err) +- { +- grub_free (split_key); +- return err; +- } +- +- gcry_err = grub_cryptodisk_decrypt (dev, split_key, length, 0, +- GRUB_LUKS1_LOG_SECTOR_SIZE); +- if (gcry_err) +- { +- grub_free (split_key); +- return grub_crypto_gcry_error (gcry_err); +- } +- +- /* Merge the decrypted key material to get the candidate master key. */ +- gcry_err = AF_merge (dev->hash, split_key, candidate_key, keysize, +- grub_be_to_cpu32 (header.keyblock[i].stripes)); +- if (gcry_err) +- { +- grub_free (split_key); +- return grub_crypto_gcry_error (gcry_err); +- } +- +- grub_dprintf ("luks", "candidate key recovered\n"); +- +- /* Calculate the PBKDF2 of the candidate master key. */ +- gcry_err = grub_crypto_pbkdf2 (dev->hash, candidate_key, +- grub_be_to_cpu32 (header.keyBytes), +- header.mkDigestSalt, +- sizeof (header.mkDigestSalt), +- grub_be_to_cpu32 +- (header.mkDigestIterations), +- candidate_digest, +- sizeof (candidate_digest)); +- if (gcry_err) +- { +- grub_free (split_key); +- return grub_crypto_gcry_error (gcry_err); +- } +- +- /* Compare the calculated PBKDF2 to the digest stored +- in the header to see if it's correct. */ +- if (grub_memcmp (candidate_digest, header.mkDigest, +- sizeof (header.mkDigest)) != 0) +- { +- grub_dprintf ("luks", "bad digest\n"); +- continue; +- } +- +- /* TRANSLATORS: It's a cryptographic key slot: one element of an array +- where each element is either empty or holds a key. */ +- grub_printf_ (N_("Slot %d opened\n"), i); +- +- /* Set the master key. */ +- gcry_err = grub_cryptodisk_setkey (dev, candidate_key, keysize); +- if (gcry_err) +- { +- grub_free (split_key); +- return grub_crypto_gcry_error (gcry_err); +- } +- +- grub_free (split_key); +- +- return GRUB_ERR_NONE; ++ grub_printf_ (N_("Failed to decrypt master key.\n")); ++ if (--attempts) grub_printf_ (N_("%u attempt%s remaining.\n"), attempts, ++ (attempts==1) ? "" : "s"); + } + + grub_free (split_key); +-- +2.30.0 + |