shared: add generic user/group record structures and JSON parsers

1 files changed, 375 insertions, 0 deletions

diff --git a/src/shared/user-record.h b/src/shared/user-record.h
new file mode 100644
index 0000000000..5bac304767
--- /dev/null
+++ b/src/shared/user-record.h
@@ -0,0 +1,375 @@
+/* SPDX-License-Identifier: LGPL-2.1+ */
+#pragma once
+
+#include <inttypes.h>
+#include <sys/types.h>
+
+#include "sd-id128.h"
+
+#include "json.h"
+#include "missing_resource.h"
+#include "time-util.h"
+
+/* But some limits on disk sizes: not less than 5M, not more than 5T */
+#define USER_DISK_SIZE_MIN (UINT64_C(5)*1024*1024)
+#define USER_DISK_SIZE_MAX (UINT64_C(5)*1024*1024*1024*1024)
+
+/* The default disk size to use when nothing else is specified, relative to free disk space */
+#define USER_DISK_SIZE_DEFAULT_PERCENT 85
+
+typedef enum UserDisposition {
+        USER_INTRINSIC,   /* root and nobody */
+        USER_SYSTEM,      /* statically allocated users for system services */
+        USER_DYNAMIC,     /* dynamically allocated users for system services */
+        USER_REGULAR,     /* regular (typically human users) */
+        USER_CONTAINER,   /* UID ranges allocated for container uses */
+        USER_RESERVED,    /* Range above 2^31 */
+        _USER_DISPOSITION_MAX,
+        _USER_DISPOSITION_INVALID = -1,
+} UserDisposition;
+
+typedef enum UserHomeStorage {
+        USER_CLASSIC,
+        USER_LUKS,
+        USER_DIRECTORY, /* A directory, and a .identity file in it, which USER_CLASSIC lacks */
+        USER_SUBVOLUME,
+        USER_FSCRYPT,
+        USER_CIFS,
+        _USER_STORAGE_MAX,
+        _USER_STORAGE_INVALID = -1
+} UserStorage;
+
+typedef enum UserRecordMask {
+        /* The various sections an identity record may have, as bit mask */
+        USER_RECORD_REGULAR     = 1U << 0,
+        USER_RECORD_SECRET      = 1U << 1,
+        USER_RECORD_PRIVILEGED  = 1U << 2,
+        USER_RECORD_PER_MACHINE = 1U << 3,
+        USER_RECORD_BINDING     = 1U << 4,
+        USER_RECORD_STATUS      = 1U << 5,
+        USER_RECORD_SIGNATURE   = 1U << 6,
+        _USER_RECORD_MASK_MAX   = (1U << 7)-1
+} UserRecordMask;
+
+typedef enum UserRecordLoadFlags {
+        /* A set of flags used while loading a user record from JSON data. We leave the lower 6 bits free,
+         * just as a safety precaution so that we can detect borked conversions between UserRecordMask and
+         * UserRecordLoadFlags. */
+
+        /* What to require */
+        USER_RECORD_REQUIRE_REGULAR     = USER_RECORD_REGULAR     << 7,
+        USER_RECORD_REQUIRE_SECRET      = USER_RECORD_SECRET      << 7,
+        USER_RECORD_REQUIRE_PRIVILEGED  = USER_RECORD_PRIVILEGED  << 7,
+        USER_RECORD_REQUIRE_PER_MACHINE = USER_RECORD_PER_MACHINE << 7,
+        USER_RECORD_REQUIRE_BINDING     = USER_RECORD_BINDING     << 7,
+        USER_RECORD_REQUIRE_STATUS      = USER_RECORD_STATUS      << 7,
+        USER_RECORD_REQUIRE_SIGNATURE   = USER_RECORD_SIGNATURE   << 7,
+
+        /* What to allow */
+        USER_RECORD_ALLOW_REGULAR       = USER_RECORD_REGULAR     << 14,
+        USER_RECORD_ALLOW_SECRET        = USER_RECORD_SECRET      << 14,
+        USER_RECORD_ALLOW_PRIVILEGED    = USER_RECORD_PRIVILEGED  << 14,
+        USER_RECORD_ALLOW_PER_MACHINE   = USER_RECORD_PER_MACHINE << 14,
+        USER_RECORD_ALLOW_BINDING       = USER_RECORD_BINDING     << 14,
+        USER_RECORD_ALLOW_STATUS        = USER_RECORD_STATUS      << 14,
+        USER_RECORD_ALLOW_SIGNATURE     = USER_RECORD_SIGNATURE   << 14,
+
+        /* What to strip */
+        USER_RECORD_STRIP_REGULAR       = USER_RECORD_REGULAR     << 21,
+        USER_RECORD_STRIP_SECRET        = USER_RECORD_SECRET      << 21,
+        USER_RECORD_STRIP_PRIVILEGED    = USER_RECORD_PRIVILEGED  << 21,
+        USER_RECORD_STRIP_PER_MACHINE   = USER_RECORD_PER_MACHINE << 21,
+        USER_RECORD_STRIP_BINDING       = USER_RECORD_BINDING     << 21,
+        USER_RECORD_STRIP_STATUS        = USER_RECORD_STATUS      << 21,
+        USER_RECORD_STRIP_SIGNATURE     = USER_RECORD_SIGNATURE   << 21,
+
+        /* Some special combinations that deserve explicit names */
+        USER_RECORD_LOAD_FULL           = USER_RECORD_REQUIRE_REGULAR |
+                                          USER_RECORD_ALLOW_SECRET |
+                                          USER_RECORD_ALLOW_PRIVILEGED |
+                                          USER_RECORD_ALLOW_PER_MACHINE |
+                                          USER_RECORD_ALLOW_BINDING |
+                                          USER_RECORD_ALLOW_STATUS |
+                                          USER_RECORD_ALLOW_SIGNATURE,
+
+        USER_RECORD_LOAD_REFUSE_SECRET =  USER_RECORD_REQUIRE_REGULAR |
+                                          USER_RECORD_ALLOW_PRIVILEGED |
+                                          USER_RECORD_ALLOW_PER_MACHINE |
+                                          USER_RECORD_ALLOW_BINDING |
+                                          USER_RECORD_ALLOW_STATUS |
+                                          USER_RECORD_ALLOW_SIGNATURE,
+
+        USER_RECORD_LOAD_MASK_SECRET =    USER_RECORD_REQUIRE_REGULAR |
+                                          USER_RECORD_ALLOW_PRIVILEGED |
+                                          USER_RECORD_ALLOW_PER_MACHINE |
+                                          USER_RECORD_ALLOW_BINDING |
+                                          USER_RECORD_ALLOW_STATUS |
+                                          USER_RECORD_ALLOW_SIGNATURE |
+                                          USER_RECORD_STRIP_SECRET,
+
+        USER_RECORD_EXTRACT_SECRET      = USER_RECORD_REQUIRE_SECRET |
+                                          USER_RECORD_STRIP_REGULAR |
+                                          USER_RECORD_STRIP_PRIVILEGED |
+                                          USER_RECORD_STRIP_PER_MACHINE |
+                                          USER_RECORD_STRIP_BINDING |
+                                          USER_RECORD_STRIP_STATUS |
+                                          USER_RECORD_STRIP_SIGNATURE,
+
+        USER_RECORD_LOAD_SIGNABLE       = USER_RECORD_REQUIRE_REGULAR |
+                                          USER_RECORD_ALLOW_PRIVILEGED |
+                                          USER_RECORD_ALLOW_PER_MACHINE,
+
+        USER_RECORD_EXTRACT_SIGNABLE    = USER_RECORD_LOAD_SIGNABLE |
+                                          USER_RECORD_STRIP_SECRET |
+                                          USER_RECORD_STRIP_BINDING |
+                                          USER_RECORD_STRIP_STATUS |
+                                          USER_RECORD_STRIP_SIGNATURE,
+
+        USER_RECORD_LOAD_EMBEDDED       = USER_RECORD_REQUIRE_REGULAR |
+                                          USER_RECORD_ALLOW_PRIVILEGED |
+                                          USER_RECORD_ALLOW_PER_MACHINE |
+                                          USER_RECORD_ALLOW_SIGNATURE,
+
+        USER_RECORD_EXTRACT_EMBEDDED    = USER_RECORD_LOAD_EMBEDDED |
+                                          USER_RECORD_STRIP_SECRET |
+                                          USER_RECORD_STRIP_BINDING |
+                                          USER_RECORD_STRIP_STATUS,
+
+        /* Whether to log about loader errors beyond LOG_DEBUG */
+        USER_RECORD_LOG                 = 1U << 28,
+
+        /* Whether to ignore errors and load what we can */
+        USER_RECORD_PERMISSIVE          = 1U << 29,
+} UserRecordLoadFlags;
+
+static inline UserRecordLoadFlags USER_RECORD_REQUIRE(UserRecordMask m) {
+        assert((m & ~_USER_RECORD_MASK_MAX) == 0);
+        return m << 7;
+}
+
+static inline UserRecordLoadFlags USER_RECORD_ALLOW(UserRecordMask m) {
+        assert((m & ~_USER_RECORD_MASK_MAX) == 0);
+        return m << 14;
+}
+
+static inline UserRecordLoadFlags USER_RECORD_STRIP(UserRecordMask m) {
+        assert((m & ~_USER_RECORD_MASK_MAX) == 0);
+        return m << 21;
+}
+
+static inline UserRecordMask USER_RECORD_REQUIRE_MASK(UserRecordLoadFlags f) {
+        return (f >> 7) & _USER_RECORD_MASK_MAX;
+}
+
+static inline UserRecordMask USER_RECORD_ALLOW_MASK(UserRecordLoadFlags f) {
+        return ((f >> 14) & _USER_RECORD_MASK_MAX) | USER_RECORD_REQUIRE_MASK(f);
+}
+
+static inline UserRecordMask USER_RECORD_STRIP_MASK(UserRecordLoadFlags f) {
+        return (f >> 21) & _USER_RECORD_MASK_MAX;
+}
+
+static inline JsonDispatchFlags USER_RECORD_LOAD_FLAGS_TO_JSON_DISPATCH_FLAGS(UserRecordLoadFlags flags) {
+        return (FLAGS_SET(flags, USER_RECORD_LOG) ? JSON_LOG : 0) |
+                (FLAGS_SET(flags, USER_RECORD_PERMISSIVE) ? JSON_PERMISSIVE : 0);
+}
+
+typedef struct Pkcs11EncryptedKey {
+        /* The encrypted passphrase, which can be decrypted with the private key indicated below */
+        void *data;
+        size_t size;
+
+        /* Where to find the private key to decrypt the encrypted passphrase above */
+        char *uri;
+
+        /* What to test the decrypted passphrase against to allow access (classic UNIX password hash).  Note
+         * that the decrypted passphrase is also used for unlocking LUKS and fscrypt, and if the account is
+         * backed by LUKS or fscrypt the hashed password is only an additional layer of authentication, not
+         * the only. */
+        char *hashed_password;
+} Pkcs11EncryptedKey;
+
+typedef struct UserRecord {
+        /* The following three fields are not part of the JSON record */
+        unsigned n_ref;
+        UserRecordMask mask;
+        bool incomplete; /* incomplete due to security restrictions. */
+
+        char *user_name;
+        char *realm;
+        char *user_name_and_realm_auto; /* the user_name field concatenated with '@' and the realm, if the latter is defined */
+        char *real_name;
+        char *email_address;
+        char *password_hint;
+        char *icon_name;
+        char *location;
+
+        UserDisposition disposition;
+        uint64_t last_change_usec;
+        uint64_t last_password_change_usec;
+
+        char *shell;
+        mode_t umask;
+        char **environment;
+        char *time_zone;
+        char *preferred_language;
+        int nice_level;
+        struct rlimit *rlimits[_RLIMIT_MAX];
+
+        int locked;               /* prohibit activation in general */
+        uint64_t not_before_usec; /* prohibit activation before this unix time */
+        uint64_t not_after_usec;  /* prohibit activation after this unix time */
+
+        UserStorage storage;
+        uint64_t disk_size;
+        uint64_t disk_size_relative; /* Disk size, relative to the free bytes of the medium, normalized to UINT32_MAX = 100% */
+        char *skeleton_directory;
+        mode_t access_mode;
+
+        uint64_t tasks_max;
+        uint64_t memory_high;
+        uint64_t memory_max;
+        uint64_t cpu_weight;
+        uint64_t io_weight;
+
+        bool nosuid;
+        bool nodev;
+        bool noexec;
+
+        char **hashed_password;
+        char **ssh_authorized_keys;
+        char **password;
+        char **pkcs11_pin;
+
+        char *cifs_domain;
+        char *cifs_user_name;
+        char *cifs_service;
+
+        char *image_path;
+        char *image_path_auto; /* when none is configured explicitly, this is where we place the implicit image */
+        char *home_directory;
+        char *home_directory_auto; /* when none is set explicitly, this is where we place the implicit home directory */
+
+        uid_t uid;
+        gid_t gid;
+
+        char **member_of;
+
+        char *file_system_type;
+        sd_id128_t partition_uuid;
+        sd_id128_t luks_uuid;
+        sd_id128_t file_system_uuid;
+
+        int luks_discard;
+        char *luks_cipher;
+        char *luks_cipher_mode;
+        uint64_t luks_volume_key_size;
+        char *luks_pbkdf_hash_algorithm;
+        char *luks_pbkdf_type;
+        uint64_t luks_pbkdf_time_cost_usec;
+        uint64_t luks_pbkdf_memory_cost;
+        uint64_t luks_pbkdf_parallel_threads;
+
+        uint64_t disk_usage;
+        uint64_t disk_free;
+        uint64_t disk_ceiling;
+        uint64_t disk_floor;
+
+        char *state;
+        char *service;
+        int signed_locally;
+
+        uint64_t good_authentication_counter;
+        uint64_t bad_authentication_counter;
+        uint64_t last_good_authentication_usec;
+        uint64_t last_bad_authentication_usec;
+
+        uint64_t ratelimit_begin_usec;
+        uint64_t ratelimit_count;
+        uint64_t ratelimit_interval_usec;
+        uint64_t ratelimit_burst;
+
+        int removable;
+        int enforce_password_policy;
+        int auto_login;
+
+        uint64_t stop_delay_usec;   /* How long to leave systemd --user around on log-out */
+        int kill_processes;         /* Whether to kill user processes forcibly on log-out */
+
+        /* The following exist mostly so that we can cover the full /etc/shadow set of fields */
+        uint64_t password_change_min_usec;       /* maps to .sp_min */
+        uint64_t password_change_max_usec;       /* maps to .sp_max */
+        uint64_t password_change_warn_usec;      /* maps to .sp_warn */
+        uint64_t password_change_inactive_usec;  /* maps to .sp_inact */
+        int password_change_now;                 /* Require a password change immediately on next login (.sp_lstchg = 0) */
+
+        char **pkcs11_token_uri;
+        Pkcs11EncryptedKey *pkcs11_encrypted_key;
+        size_t n_pkcs11_encrypted_key;
+        int pkcs11_protected_authentication_path_permitted;
+
+        JsonVariant *json;
+} UserRecord;
+
+UserRecord* user_record_new(void);
+UserRecord* user_record_ref(UserRecord *h);
+UserRecord* user_record_unref(UserRecord *h);
+
+DEFINE_TRIVIAL_CLEANUP_FUNC(UserRecord*, user_record_unref);
+
+int user_record_load(UserRecord *h, JsonVariant *v, UserRecordLoadFlags flags);
+int user_record_build(UserRecord **ret, ...);
+
+const char *user_record_user_name_and_realm(UserRecord *h);
+UserStorage user_record_storage(UserRecord *h);
+const char *user_record_file_system_type(UserRecord *h);
+const char *user_record_skeleton_directory(UserRecord *h);
+mode_t user_record_access_mode(UserRecord *h);
+const char *user_record_home_directory(UserRecord *h);
+const char *user_record_image_path(UserRecord *h);
+unsigned long user_record_mount_flags(UserRecord *h);
+const char *user_record_cifs_user_name(UserRecord *h);
+const char *user_record_shell(UserRecord *h);
+const char *user_record_real_name(UserRecord *h);
+bool user_record_luks_discard(UserRecord *h);
+const char *user_record_luks_cipher(UserRecord *h);
+const char *user_record_luks_cipher_mode(UserRecord *h);
+uint64_t user_record_luks_volume_key_size(UserRecord *h);
+const char* user_record_luks_pbkdf_type(UserRecord *h);
+usec_t user_record_luks_pbkdf_time_cost_usec(UserRecord *h);
+uint64_t user_record_luks_pbkdf_memory_cost(UserRecord *h);
+uint64_t user_record_luks_pbkdf_parallel_threads(UserRecord *h);
+const char *user_record_luks_pbkdf_hash_algorithm(UserRecord *h);
+gid_t user_record_gid(UserRecord *h);
+UserDisposition user_record_disposition(UserRecord *h);
+int user_record_removable(UserRecord *h);
+usec_t user_record_ratelimit_interval_usec(UserRecord *h);
+uint64_t user_record_ratelimit_burst(UserRecord *h);
+bool user_record_can_authenticate(UserRecord *h);
+
+bool user_record_equal(UserRecord *a, UserRecord *b);
+bool user_record_compatible(UserRecord *a, UserRecord *b);
+int user_record_compare_last_change(UserRecord *a, UserRecord *b);
+
+usec_t user_record_ratelimit_next_try(UserRecord *h);
+
+int user_record_clone(UserRecord *h, UserRecordLoadFlags flags, UserRecord **ret);
+int user_record_masked_equal(UserRecord *a, UserRecord *b, UserRecordMask mask);
+
+int user_record_test_blocked(UserRecord *h);
+int user_record_test_password_change_required(UserRecord *h);
+
+/* The following six are user by group-record.c, that's why we export them here */
+int json_dispatch_realm(const char *name, JsonVariant *variant, JsonDispatchFlags flags, void *userdata);
+int json_dispatch_user_group_list(const char *name, JsonVariant *variant, JsonDispatchFlags flags, void *userdata);
+int json_dispatch_user_disposition(const char *name, JsonVariant *variant, JsonDispatchFlags flags, void *userdata);
+
+int per_machine_id_match(JsonVariant *ids, JsonDispatchFlags flags);
+int per_machine_hostname_match(JsonVariant *hns, JsonDispatchFlags flags);
+int user_group_record_mangle(JsonVariant *v, UserRecordLoadFlags load_flags, JsonVariant **ret_variant, UserRecordMask *ret_mask);
+
+const char* user_storage_to_string(UserStorage t) _const_;
+UserStorage user_storage_from_string(const char *s) _pure_;
+
+const char* user_disposition_to_string(UserDisposition t) _const_;
+UserDisposition user_disposition_from_string(const char *s) _pure_;