/* SPDX-License-Identifier: LGPL-2.1-or-later */ #pragma once #include #if ENABLE_GSHADOW # include #endif #include #include #include #include #include #include /* Users managed by systemd-homed. See https://systemd.io/UIDS-GIDS for details how this range fits into the rest of the world */ #define HOME_UID_MIN ((uid_t) 60001) #define HOME_UID_MAX ((uid_t) 60513) /* Users mapped from host into a container */ #define MAP_UID_MIN ((uid_t) 60514) #define MAP_UID_MAX ((uid_t) 60577) bool uid_is_valid(uid_t uid); static inline bool gid_is_valid(gid_t gid) { return uid_is_valid((uid_t) gid); } int parse_uid(const char *s, uid_t* ret_uid); int parse_uid_range(const char *s, uid_t *ret_lower, uid_t *ret_upper); static inline int parse_gid(const char *s, gid_t *ret_gid) { return parse_uid(s, (uid_t*) ret_gid); } char* getlogname_malloc(void); char* getusername_malloc(void); typedef enum UserCredsFlags { USER_CREDS_PREFER_NSS = 1 << 0, /* if set, only synthesize user records if database lacks them. Normally we bypass the userdb entirely for the records we can synthesize */ USER_CREDS_ALLOW_MISSING = 1 << 1, /* if a numeric UID string is resolved, be OK if there's no record for it */ USER_CREDS_CLEAN = 1 << 2, /* try to clean up shell and home fields with invalid data */ } UserCredsFlags; int get_user_creds(const char **username, uid_t *ret_uid, gid_t *ret_gid, const char **ret_home, const char **ret_shell, UserCredsFlags flags); int get_group_creds(const char **groupname, gid_t *ret_gid, UserCredsFlags flags); char* uid_to_name(uid_t uid); char* gid_to_name(gid_t gid); int in_gid(gid_t gid); int in_group(const char *name); int merge_gid_lists(const gid_t *list1, size_t size1, const gid_t *list2, size_t size2, gid_t **result); int getgroups_alloc(gid_t** gids); int get_home_dir(char **ret); int get_shell(char **ret); int fully_set_uid_gid(uid_t uid, gid_t gid, const gid_t supplementary_gids[], size_t n_supplementary_gids); static inline int reset_uid_gid(void) { return fully_set_uid_gid(0, 0, NULL, 0); } int take_etc_passwd_lock(const char *root); #define UID_INVALID ((uid_t) -1) #define GID_INVALID ((gid_t) -1) #define UID_NOBODY ((uid_t) 65534U) #define GID_NOBODY ((gid_t) 65534U) /* If REMOUNT_IDMAPPING_HOST_ROOT is set for remount_idmap() we'll include a mapping here that maps the host * root user accessing the idmapped mount to the this user ID on the backing fs. This is the last valid UID in * the *signed* 32-bit range. You might wonder why precisely use this specific UID for this purpose? Well, we * definitely cannot use the first 0…65536 UIDs for that, since in most cases that's precisely the file range * we intend to map to some high UID range, and since UID mappings have to be bijective we thus cannot use * them at all. Furthermore the UID range beyond INT32_MAX (i.e. the range above the signed 32-bit range) is * icky, since many APIs cannot use it (example: setfsuid() returns the old UID as signed integer). Following * our usual logic of assigning a 16-bit UID range to each container, so that the upper 16-bit of a 32-bit UID * value indicate kind of a "container ID" and the lower 16-bit map directly to the intended user you can read * this specific UID as the "nobody" user of the container with ID 0x7FFF, which is kinda nice. */ #define UID_MAPPED_ROOT ((uid_t) (INT32_MAX-1)) #define GID_MAPPED_ROOT ((gid_t) (INT32_MAX-1)) #define ETC_PASSWD_LOCK_FILENAME ".pwd.lock" #define ETC_PASSWD_LOCK_PATH "/etc/" ETC_PASSWD_LOCK_FILENAME /* The following macros add 1 when converting things, since UID 0 is a valid UID, while the pointer * NULL is special */ #define PTR_TO_UID(p) ((uid_t) (((uintptr_t) (p))-1)) #define UID_TO_PTR(u) ((void*) (((uintptr_t) (u))+1)) #define PTR_TO_GID(p) ((gid_t) (((uintptr_t) (p))-1)) #define GID_TO_PTR(u) ((void*) (((uintptr_t) (u))+1)) static inline bool userns_supported(void) { return access("/proc/self/uid_map", F_OK) >= 0; } typedef enum ValidUserFlags { VALID_USER_RELAX = 1 << 0, VALID_USER_WARN = 1 << 1, VALID_USER_ALLOW_NUMERIC = 1 << 2, } ValidUserFlags; bool valid_user_group_name(const char *u, ValidUserFlags flags); bool valid_gecos(const char *d); char* mangle_gecos(const char *d); bool valid_home(const char *p); bool valid_shell(const char *p); int maybe_setgroups(size_t size, const gid_t *list); bool synthesize_nobody(void); int fgetpwent_sane(FILE *stream, struct passwd **pw); int fgetspent_sane(FILE *stream, struct spwd **sp); int fgetgrent_sane(FILE *stream, struct group **gr); int putpwent_sane(const struct passwd *pw, FILE *stream); int putspent_sane(const struct spwd *sp, FILE *stream); int putgrent_sane(const struct group *gr, FILE *stream); #if ENABLE_GSHADOW int fgetsgent_sane(FILE *stream, struct sgrp **sg); int putsgent_sane(const struct sgrp *sg, FILE *stream); #endif bool is_nologin_shell(const char *shell); const char* default_root_shell_at(int rfd); const char* default_root_shell(const char *root); int is_this_me(const char *username); const char* get_home_root(void); static inline bool hashed_password_is_locked_or_invalid(const char *password) { return password && password[0] != '$'; } /* A locked *and* invalid password for "struct spwd"'s .sp_pwdp and "struct passwd"'s .pw_passwd field */ #define PASSWORD_LOCKED_AND_INVALID "!*" /* A password indicating "look in shadow file, please!" for "struct passwd"'s .pw_passwd */ #define PASSWORD_SEE_SHADOW "x" /* A password indicating "hey, no password required for login" */ #define PASSWORD_NONE "" /* Used by sysusers to indicate that the password should be filled in by firstboot. * Also see https://github.com/systemd/systemd/pull/24680#pullrequestreview-1439464325. */ #define PASSWORD_UNPROVISIONED "!unprovisioned" int getpwuid_malloc(uid_t uid, struct passwd **ret); int getpwnam_malloc(const char *name, struct passwd **ret); int getgrnam_malloc(const char *name, struct group **ret); int getgrgid_malloc(gid_t gid, struct group **ret);