| /* SPDX-License-Identifier: LGPL-2.1-or-later */ |
| |
| #include <linux/fs.h> |
| #include <openssl/evp.h> |
| #include <openssl/sha.h> |
| #include <sys/ioctl.h> |
| #include <sys/xattr.h> |
| |
| #include "errno-util.h" |
| #include "fd-util.h" |
| #include "hexdecoct.h" |
| #include "homework-fscrypt.h" |
| #include "homework-mount.h" |
| #include "homework-quota.h" |
| #include "memory-util.h" |
| #include "missing_keyctl.h" |
| #include "missing_syscall.h" |
| #include "mkdir.h" |
| #include "mount-util.h" |
| #include "nulstr-util.h" |
| #include "openssl-util.h" |
| #include "parse-util.h" |
| #include "process-util.h" |
| #include "random-util.h" |
| #include "rm-rf.h" |
| #include "stdio-util.h" |
| #include "strv.h" |
| #include "tmpfile-util.h" |
| #include "user-util.h" |
| #include "xattr-util.h" |
| |
| static int fscrypt_upload_volume_key( |
| const uint8_t key_descriptor[static FS_KEY_DESCRIPTOR_SIZE], |
| const void *volume_key, |
| size_t volume_key_size, |
| key_serial_t where) { |
| |
| _cleanup_free_ char *hex = NULL; |
| const char *description; |
| struct fscrypt_key key; |
| key_serial_t serial; |
| |
| assert(key_descriptor); |
| assert(volume_key); |
| assert(volume_key_size > 0); |
| |
| if (volume_key_size > sizeof(key.raw)) |
| return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Volume key too long."); |
| |
| hex = hexmem(key_descriptor, FS_KEY_DESCRIPTOR_SIZE); |
| if (!hex) |
| return log_oom(); |
| |
| description = strjoina("fscrypt:", hex); |
| |
| key = (struct fscrypt_key) { |
| .size = volume_key_size, |
| }; |
| memcpy(key.raw, volume_key, volume_key_size); |
| |
| CLEANUP_ERASE(key); |
| |
| /* Upload to the kernel */ |
| serial = add_key("logon", description, &key, sizeof(key), where); |
| if (serial < 0) |
| return log_error_errno(errno, "Failed to install master key in keyring: %m"); |
| |
| log_info("Uploaded encryption key to kernel."); |
| |
| return 0; |
| } |
| |
| static void calculate_key_descriptor( |
| const void *key, |
| size_t key_size, |
| uint8_t ret_key_descriptor[static FS_KEY_DESCRIPTOR_SIZE]) { |
| |
| uint8_t hashed[512 / 8] = {}, hashed2[512 / 8] = {}; |
| |
| /* Derive the key descriptor from the volume key via double SHA512, in order to be compatible with e4crypt */ |
| |
| assert_se(SHA512(key, key_size, hashed) == hashed); |
| assert_se(SHA512(hashed, sizeof(hashed), hashed2) == hashed2); |
| |
| assert_cc(sizeof(hashed2) >= FS_KEY_DESCRIPTOR_SIZE); |
| |
| memcpy(ret_key_descriptor, hashed2, FS_KEY_DESCRIPTOR_SIZE); |
| } |
| |
| static int fscrypt_slot_try_one( |
| const char *password, |
| const void *salt, size_t salt_size, |
| const void *encrypted, size_t encrypted_size, |
| const uint8_t match_key_descriptor[static FS_KEY_DESCRIPTOR_SIZE], |
| void **ret_decrypted, size_t *ret_decrypted_size) { |
| |
| |
| _cleanup_(EVP_CIPHER_CTX_freep) EVP_CIPHER_CTX *context = NULL; |
| _cleanup_(erase_and_freep) void *decrypted = NULL; |
| uint8_t key_descriptor[FS_KEY_DESCRIPTOR_SIZE]; |
| int decrypted_size_out1, decrypted_size_out2; |
| uint8_t derived[512 / 8] = {}; |
| size_t decrypted_size; |
| const EVP_CIPHER *cc; |
| int r; |
| |
| assert(password); |
| assert(salt); |
| assert(salt_size > 0); |
| assert(encrypted); |
| assert(encrypted_size > 0); |
| assert(match_key_descriptor); |
| |
| /* Our construction is like this: |
| * |
| * 1. In each key slot we store a salt value plus the encrypted volume key |
| * |
| * 2. Unlocking is via calculating PBKDF2-HMAC-SHA512 of the supplied password (in combination with |
| * the salt), then using the first 256 bit of the hash as key for decrypting the encrypted |
| * volume key in AES256 counter mode. |
| * |
| * 3. Writing a password is similar: calculate PBKDF2-HMAC-SHA512 of the supplied password (in |
| * combination with the salt), then encrypt the volume key in AES256 counter mode with the |
| * resulting hash. |
| */ |
| |
| CLEANUP_ERASE(derived); |
| |
| if (PKCS5_PBKDF2_HMAC( |
| password, strlen(password), |
| salt, salt_size, |
| 0xFFFF, EVP_sha512(), |
| sizeof(derived), derived) != 1) |
| return log_error_errno(SYNTHETIC_ERRNO(ENOTRECOVERABLE), "PBKDF2 failed"); |
| |
| context = EVP_CIPHER_CTX_new(); |
| if (!context) |
| return log_oom(); |
| |
| /* We use AES256 in counter mode */ |
| assert_se(cc = EVP_aes_256_ctr()); |
| |
| /* We only use the first half of the derived key */ |
| assert(sizeof(derived) >= (size_t) EVP_CIPHER_key_length(cc)); |
| |
| if (EVP_DecryptInit_ex(context, cc, NULL, derived, NULL) != 1) |
| return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Failed to initialize decryption context."); |
| |
| decrypted_size = encrypted_size + EVP_CIPHER_key_length(cc) * 2; |
| decrypted = malloc(decrypted_size); |
| if (!decrypted) |
| return log_oom(); |
| |
| if (EVP_DecryptUpdate(context, (uint8_t*) decrypted, &decrypted_size_out1, encrypted, encrypted_size) != 1) |
| return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Failed to decrypt volume key."); |
| |
| assert((size_t) decrypted_size_out1 <= decrypted_size); |
| |
| if (EVP_DecryptFinal_ex(context, (uint8_t*) decrypted_size + decrypted_size_out1, &decrypted_size_out2) != 1) |
| return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Failed to finish decryption of volume key."); |
| |
| assert((size_t) decrypted_size_out1 + (size_t) decrypted_size_out2 < decrypted_size); |
| decrypted_size = (size_t) decrypted_size_out1 + (size_t) decrypted_size_out2; |
| |
| calculate_key_descriptor(decrypted, decrypted_size, key_descriptor); |
| |
| if (memcmp(key_descriptor, match_key_descriptor, FS_KEY_DESCRIPTOR_SIZE) != 0) |
| return -ENOANO; /* don't log here */ |
| |
| r = fscrypt_upload_volume_key(key_descriptor, decrypted, decrypted_size, KEY_SPEC_THREAD_KEYRING); |
| if (r < 0) |
| return r; |
| |
| if (ret_decrypted) |
| *ret_decrypted = TAKE_PTR(decrypted); |
| if (ret_decrypted_size) |
| *ret_decrypted_size = decrypted_size; |
| |
| return 0; |
| } |
| |
| static int fscrypt_slot_try_many( |
| char **passwords, |
| const void *salt, size_t salt_size, |
| const void *encrypted, size_t encrypted_size, |
| const uint8_t match_key_descriptor[static FS_KEY_DESCRIPTOR_SIZE], |
| void **ret_decrypted, size_t *ret_decrypted_size) { |
| |
| int r; |
| |
| STRV_FOREACH(i, passwords) { |
| r = fscrypt_slot_try_one(*i, salt, salt_size, encrypted, encrypted_size, match_key_descriptor, ret_decrypted, ret_decrypted_size); |
| if (r != -ENOANO) |
| return r; |
| } |
| |
| return -ENOANO; |
| } |
| |
| static int fscrypt_setup( |
| const PasswordCache *cache, |
| char **password, |
| HomeSetup *setup, |
| void **ret_volume_key, |
| size_t *ret_volume_key_size) { |
| |
| _cleanup_free_ char *xattr_buf = NULL; |
| int r; |
| |
| assert(setup); |
| assert(setup->root_fd >= 0); |
| |
| r = flistxattr_malloc(setup->root_fd, &xattr_buf); |
| if (r < 0) |
| return log_error_errno(errno, "Failed to retrieve xattr list: %m"); |
| |
| NULSTR_FOREACH(xa, xattr_buf) { |
| _cleanup_free_ void *salt = NULL, *encrypted = NULL; |
| _cleanup_free_ char *value = NULL; |
| size_t salt_size, encrypted_size; |
| const char *nr, *e; |
| char **list; |
| int n; |
| |
| /* Check if this xattr has the format 'trusted.fscrypt_slot<nr>' where '<nr>' is a 32bit unsigned integer */ |
| nr = startswith(xa, "trusted.fscrypt_slot"); |
| if (!nr) |
| continue; |
| if (safe_atou32(nr, NULL) < 0) |
| continue; |
| |
| n = fgetxattr_malloc(setup->root_fd, xa, &value); |
| if (n == -ENODATA) /* deleted by now? */ |
| continue; |
| if (n < 0) |
| return log_error_errno(n, "Failed to read %s xattr: %m", xa); |
| |
| e = memchr(value, ':', n); |
| if (!e) |
| return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "xattr %s lacks ':' separator: %m", xa); |
| |
| r = unbase64mem(value, e - value, &salt, &salt_size); |
| if (r < 0) |
| return log_error_errno(r, "Failed to decode salt of %s: %m", xa); |
| r = unbase64mem(e+1, n - (e - value) - 1, &encrypted, &encrypted_size); |
| if (r < 0) |
| return log_error_errno(r, "Failed to decode encrypted key of %s: %m", xa); |
| |
| r = -ENOANO; |
| FOREACH_POINTER(list, cache->pkcs11_passwords, cache->fido2_passwords, password) { |
| r = fscrypt_slot_try_many( |
| list, |
| salt, salt_size, |
| encrypted, encrypted_size, |
| setup->fscrypt_key_descriptor, |
| ret_volume_key, ret_volume_key_size); |
| if (r != -ENOANO) |
| break; |
| } |
| if (r < 0) { |
| if (r != -ENOANO) |
| return r; |
| } else |
| return 0; |
| } |
| |
| return log_error_errno(SYNTHETIC_ERRNO(ENOKEY), "Failed to set up home directory with provided passwords."); |
| } |
| |
| int home_setup_fscrypt( |
| UserRecord *h, |
| HomeSetup *setup, |
| const PasswordCache *cache) { |
| |
| _cleanup_(erase_and_freep) void *volume_key = NULL; |
| struct fscrypt_policy policy = {}; |
| size_t volume_key_size = 0; |
| const char *ip; |
| int r; |
| |
| assert(h); |
| assert(user_record_storage(h) == USER_FSCRYPT); |
| assert(setup); |
| assert(setup->root_fd < 0); |
| |
| assert_se(ip = user_record_image_path(h)); |
| |
| setup->root_fd = open(ip, O_RDONLY|O_CLOEXEC|O_DIRECTORY); |
| if (setup->root_fd < 0) |
| return log_error_errno(errno, "Failed to open home directory: %m"); |
| |
| if (ioctl(setup->root_fd, FS_IOC_GET_ENCRYPTION_POLICY, &policy) < 0) { |
| if (errno == ENODATA) |
| return log_error_errno(errno, "Home directory %s is not encrypted.", ip); |
| if (ERRNO_IS_NOT_SUPPORTED(errno)) { |
| log_error_errno(errno, "File system does not support fscrypt: %m"); |
| return -ENOLINK; /* make recognizable */ |
| } |
| return log_error_errno(errno, "Failed to acquire encryption policy of %s: %m", ip); |
| } |
| |
| memcpy(setup->fscrypt_key_descriptor, policy.master_key_descriptor, FS_KEY_DESCRIPTOR_SIZE); |
| |
| r = fscrypt_setup( |
| cache, |
| h->password, |
| setup, |
| &volume_key, |
| &volume_key_size); |
| if (r < 0) |
| return r; |
| |
| /* Also install the access key in the user's own keyring */ |
| |
| if (uid_is_valid(h->uid)) { |
| r = safe_fork("(sd-addkey)", |
| FORK_RESET_SIGNALS|FORK_CLOSE_ALL_FDS|FORK_DEATHSIG|FORK_LOG|FORK_WAIT|FORK_REOPEN_LOG, |
| NULL); |
| if (r < 0) |
| return log_error_errno(r, "Failed install encryption key in user's keyring: %m"); |
| if (r == 0) { |
| gid_t gid; |
| |
| /* Child */ |
| |
| gid = user_record_gid(h); |
| if (setresgid(gid, gid, gid) < 0) { |
| log_error_errno(errno, "Failed to change GID to " GID_FMT ": %m", gid); |
| _exit(EXIT_FAILURE); |
| } |
| |
| if (setgroups(0, NULL) < 0) { |
| log_error_errno(errno, "Failed to reset auxiliary groups list: %m"); |
| _exit(EXIT_FAILURE); |
| } |
| |
| if (setresuid(h->uid, h->uid, h->uid) < 0) { |
| log_error_errno(errno, "Failed to change UID to " UID_FMT ": %m", h->uid); |
| _exit(EXIT_FAILURE); |
| } |
| |
| r = fscrypt_upload_volume_key( |
| setup->fscrypt_key_descriptor, |
| volume_key, |
| volume_key_size, |
| KEY_SPEC_USER_KEYRING); |
| if (r < 0) |
| _exit(EXIT_FAILURE); |
| |
| _exit(EXIT_SUCCESS); |
| } |
| } |
| |
| /* We'll bind mount the image directory to a new mount point where we'll start adjusting it. Only |
| * once that's complete we'll move the thing to its final place eventually. */ |
| r = home_unshare_and_mkdir(); |
| if (r < 0) |
| return r; |
| |
| r = mount_follow_verbose(LOG_ERR, ip, HOME_RUNTIME_WORK_DIR, NULL, MS_BIND, NULL); |
| if (r < 0) |
| return r; |
| |
| setup->undo_mount = true; |
| |
| /* Turn off any form of propagation for this */ |
| r = mount_nofollow_verbose(LOG_ERR, NULL, HOME_RUNTIME_WORK_DIR, NULL, MS_PRIVATE, NULL); |
| if (r < 0) |
| return r; |
| |
| /* Adjust MS_SUID and similar flags */ |
| r = mount_nofollow_verbose(LOG_ERR, NULL, HOME_RUNTIME_WORK_DIR, NULL, MS_BIND|MS_REMOUNT|user_record_mount_flags(h), NULL); |
| if (r < 0) |
| return r; |
| |
| safe_close(setup->root_fd); |
| setup->root_fd = open(HOME_RUNTIME_WORK_DIR, O_RDONLY|O_CLOEXEC|O_DIRECTORY|O_NOFOLLOW); |
| if (setup->root_fd < 0) |
| return log_error_errno(errno, "Failed to open home directory: %m"); |
| |
| return 0; |
| } |
| |
| static int fscrypt_slot_set( |
| int root_fd, |
| const void *volume_key, |
| size_t volume_key_size, |
| const char *password, |
| uint32_t nr) { |
| |
| _cleanup_free_ char *salt_base64 = NULL, *encrypted_base64 = NULL, *joined = NULL; |
| char label[STRLEN("trusted.fscrypt_slot") + DECIMAL_STR_MAX(nr) + 1]; |
| _cleanup_(EVP_CIPHER_CTX_freep) EVP_CIPHER_CTX *context = NULL; |
| int r, encrypted_size_out1, encrypted_size_out2; |
| uint8_t salt[64], derived[512 / 8] = {}; |
| _cleanup_free_ void *encrypted = NULL; |
| const EVP_CIPHER *cc; |
| size_t encrypted_size; |
| ssize_t ss; |
| |
| r = crypto_random_bytes(salt, sizeof(salt)); |
| if (r < 0) |
| return log_error_errno(r, "Failed to generate salt: %m"); |
| |
| CLEANUP_ERASE(derived); |
| |
| if (PKCS5_PBKDF2_HMAC( |
| password, strlen(password), |
| salt, sizeof(salt), |
| 0xFFFF, EVP_sha512(), |
| sizeof(derived), derived) != 1) |
| return log_error_errno(SYNTHETIC_ERRNO(ENOTRECOVERABLE), "PBKDF2 failed"); |
| |
| context = EVP_CIPHER_CTX_new(); |
| if (!context) |
| return log_oom(); |
| |
| /* We use AES256 in counter mode */ |
| cc = EVP_aes_256_ctr(); |
| |
| /* We only use the first half of the derived key */ |
| assert(sizeof(derived) >= (size_t) EVP_CIPHER_key_length(cc)); |
| |
| if (EVP_EncryptInit_ex(context, cc, NULL, derived, NULL) != 1) |
| return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Failed to initialize encryption context."); |
| |
| encrypted_size = volume_key_size + EVP_CIPHER_key_length(cc) * 2; |
| encrypted = malloc(encrypted_size); |
| if (!encrypted) |
| return log_oom(); |
| |
| if (EVP_EncryptUpdate(context, (uint8_t*) encrypted, &encrypted_size_out1, volume_key, volume_key_size) != 1) |
| return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Failed to encrypt volume key."); |
| |
| assert((size_t) encrypted_size_out1 <= encrypted_size); |
| |
| if (EVP_EncryptFinal_ex(context, (uint8_t*) encrypted_size + encrypted_size_out1, &encrypted_size_out2) != 1) |
| return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Failed to finish encryption of volume key."); |
| |
| assert((size_t) encrypted_size_out1 + (size_t) encrypted_size_out2 < encrypted_size); |
| encrypted_size = (size_t) encrypted_size_out1 + (size_t) encrypted_size_out2; |
| |
| ss = base64mem(salt, sizeof(salt), &salt_base64); |
| if (ss < 0) |
| return log_oom(); |
| |
| ss = base64mem(encrypted, encrypted_size, &encrypted_base64); |
| if (ss < 0) |
| return log_oom(); |
| |
| joined = strjoin(salt_base64, ":", encrypted_base64); |
| if (!joined) |
| return log_oom(); |
| |
| xsprintf(label, "trusted.fscrypt_slot%" PRIu32, nr); |
| if (fsetxattr(root_fd, label, joined, strlen(joined), 0) < 0) |
| return log_error_errno(errno, "Failed to write xattr %s: %m", label); |
| |
| log_info("Written key slot %s.", label); |
| |
| return 0; |
| } |
| |
| int home_create_fscrypt( |
| UserRecord *h, |
| HomeSetup *setup, |
| char **effective_passwords, |
| UserRecord **ret_home) { |
| |
| _cleanup_(rm_rf_physical_and_freep) char *temporary = NULL; |
| _cleanup_(user_record_unrefp) UserRecord *new_home = NULL; |
| _cleanup_(erase_and_freep) void *volume_key = NULL; |
| _cleanup_close_ int mount_fd = -EBADF; |
| struct fscrypt_policy policy = {}; |
| size_t volume_key_size = 512 / 8; |
| _cleanup_free_ char *d = NULL; |
| uint32_t nr = 0; |
| const char *ip; |
| int r; |
| |
| assert(h); |
| assert(user_record_storage(h) == USER_FSCRYPT); |
| assert(setup); |
| assert(ret_home); |
| |
| assert_se(ip = user_record_image_path(h)); |
| |
| r = tempfn_random(ip, "homework", &d); |
| if (r < 0) |
| return log_error_errno(r, "Failed to allocate temporary directory: %m"); |
| |
| (void) mkdir_parents(d, 0755); |
| |
| if (mkdir(d, 0700) < 0) |
| return log_error_errno(errno, "Failed to create temporary home directory %s: %m", d); |
| |
| temporary = TAKE_PTR(d); /* Needs to be destroyed now */ |
| |
| r = home_unshare_and_mkdir(); |
| if (r < 0) |
| return r; |
| |
| setup->root_fd = open(temporary, O_RDONLY|O_CLOEXEC|O_DIRECTORY|O_NOFOLLOW); |
| if (setup->root_fd < 0) |
| return log_error_errno(errno, "Failed to open temporary home directory: %m"); |
| |
| if (ioctl(setup->root_fd, FS_IOC_GET_ENCRYPTION_POLICY, &policy) < 0) { |
| if (ERRNO_IS_NOT_SUPPORTED(errno)) { |
| log_error_errno(errno, "File system does not support fscrypt: %m"); |
| return -ENOLINK; /* make recognizable */ |
| } |
| if (errno != ENODATA) |
| return log_error_errno(errno, "Failed to get fscrypt policy of directory: %m"); |
| } else |
| return log_error_errno(SYNTHETIC_ERRNO(EBUSY), "Parent of %s already encrypted, refusing.", d); |
| |
| volume_key = malloc(volume_key_size); |
| if (!volume_key) |
| return log_oom(); |
| |
| r = crypto_random_bytes(volume_key, volume_key_size); |
| if (r < 0) |
| return log_error_errno(r, "Failed to acquire volume key: %m"); |
| |
| log_info("Generated volume key of size %zu.", volume_key_size); |
| |
| policy = (struct fscrypt_policy) { |
| .contents_encryption_mode = FS_ENCRYPTION_MODE_AES_256_XTS, |
| .filenames_encryption_mode = FS_ENCRYPTION_MODE_AES_256_CTS, |
| .flags = FS_POLICY_FLAGS_PAD_32, |
| }; |
| |
| calculate_key_descriptor(volume_key, volume_key_size, policy.master_key_descriptor); |
| |
| r = fscrypt_upload_volume_key(policy.master_key_descriptor, volume_key, volume_key_size, KEY_SPEC_THREAD_KEYRING); |
| if (r < 0) |
| return r; |
| |
| log_info("Uploaded volume key to kernel."); |
| |
| if (ioctl(setup->root_fd, FS_IOC_SET_ENCRYPTION_POLICY, &policy) < 0) |
| return log_error_errno(errno, "Failed to set fscrypt policy on directory: %m"); |
| |
| log_info("Encryption policy set."); |
| |
| STRV_FOREACH(i, effective_passwords) { |
| r = fscrypt_slot_set(setup->root_fd, volume_key, volume_key_size, *i, nr); |
| if (r < 0) |
| return r; |
| |
| nr++; |
| } |
| |
| (void) home_update_quota_classic(h, temporary); |
| |
| r = home_shift_uid(setup->root_fd, HOME_RUNTIME_WORK_DIR, h->uid, h->uid, &mount_fd); |
| if (r > 0) |
| setup->undo_mount = true; /* If uidmaps worked we have a mount to undo again */ |
| |
| if (mount_fd >= 0) { |
| /* If we have established a new mount, then we can use that as new root fd to our home directory. */ |
| safe_close(setup->root_fd); |
| |
| setup->root_fd = fd_reopen(mount_fd, O_RDONLY|O_CLOEXEC|O_DIRECTORY); |
| if (setup->root_fd < 0) |
| return log_error_errno(setup->root_fd, "Unable to convert mount fd into proper directory fd: %m"); |
| |
| mount_fd = safe_close(mount_fd); |
| } |
| |
| r = home_populate(h, setup->root_fd); |
| if (r < 0) |
| return r; |
| |
| r = home_sync_and_statfs(setup->root_fd, NULL); |
| if (r < 0) |
| return r; |
| |
| r = user_record_clone(h, USER_RECORD_LOAD_MASK_SECRET|USER_RECORD_PERMISSIVE, &new_home); |
| if (r < 0) |
| return log_error_errno(r, "Failed to clone record: %m"); |
| |
| r = user_record_add_binding( |
| new_home, |
| USER_FSCRYPT, |
| ip, |
| SD_ID128_NULL, |
| SD_ID128_NULL, |
| SD_ID128_NULL, |
| NULL, |
| NULL, |
| UINT64_MAX, |
| NULL, |
| NULL, |
| h->uid, |
| (gid_t) h->uid); |
| if (r < 0) |
| return log_error_errno(r, "Failed to add binding to record: %m"); |
| |
| setup->root_fd = safe_close(setup->root_fd); |
| |
| r = home_setup_undo_mount(setup, LOG_ERR); |
| if (r < 0) |
| return r; |
| |
| if (rename(temporary, ip) < 0) |
| return log_error_errno(errno, "Failed to rename %s to %s: %m", temporary, ip); |
| |
| temporary = mfree(temporary); |
| |
| log_info("Everything completed."); |
| |
| *ret_home = TAKE_PTR(new_home); |
| return 0; |
| } |
| |
| int home_passwd_fscrypt( |
| UserRecord *h, |
| HomeSetup *setup, |
| const PasswordCache *cache, /* the passwords acquired via PKCS#11/FIDO2 security tokens */ |
| char **effective_passwords /* new passwords */) { |
| |
| _cleanup_(erase_and_freep) void *volume_key = NULL; |
| _cleanup_free_ char *xattr_buf = NULL; |
| size_t volume_key_size = 0; |
| uint32_t slot = 0; |
| int r; |
| |
| assert(h); |
| assert(user_record_storage(h) == USER_FSCRYPT); |
| assert(setup); |
| |
| r = fscrypt_setup( |
| cache, |
| h->password, |
| setup, |
| &volume_key, |
| &volume_key_size); |
| if (r < 0) |
| return r; |
| |
| STRV_FOREACH(p, effective_passwords) { |
| r = fscrypt_slot_set(setup->root_fd, volume_key, volume_key_size, *p, slot); |
| if (r < 0) |
| return r; |
| |
| slot++; |
| } |
| |
| r = flistxattr_malloc(setup->root_fd, &xattr_buf); |
| if (r < 0) |
| return log_error_errno(errno, "Failed to retrieve xattr list: %m"); |
| |
| NULSTR_FOREACH(xa, xattr_buf) { |
| const char *nr; |
| uint32_t z; |
| |
| /* Check if this xattr has the format 'trusted.fscrypt_slot<nr>' where '<nr>' is a 32bit unsigned integer */ |
| nr = startswith(xa, "trusted.fscrypt_slot"); |
| if (!nr) |
| continue; |
| if (safe_atou32(nr, &z) < 0) |
| continue; |
| |
| if (z < slot) |
| continue; |
| |
| if (fremovexattr(setup->root_fd, xa) < 0) |
| if (errno != ENODATA) |
| log_warning_errno(errno, "Failed to remove xattr %s: %m", xa); |
| } |
| |
| return 0; |
| } |
