diff options
Diffstat (limited to 'src/basic/user-util.h')
-rw-r--r-- | src/basic/user-util.h | 115 |
1 files changed, 115 insertions, 0 deletions
diff --git a/src/basic/user-util.h b/src/basic/user-util.h new file mode 100644 index 0000000..cc899ee --- /dev/null +++ b/src/basic/user-util.h @@ -0,0 +1,115 @@ +/* SPDX-License-Identifier: LGPL-2.1+ */ +#pragma once + +#include <grp.h> +#if ENABLE_GSHADOW +#include <gshadow.h> +#endif +#include <pwd.h> +#include <shadow.h> +#include <stdbool.h> +#include <stdint.h> +#include <sys/types.h> +#include <unistd.h> + +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); + +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 *uid, gid_t *gid, const char **home, const char **shell, UserCredsFlags flags); +int get_group_creds(const char **groupname, gid_t *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 get_home_dir(char **ret); +int get_shell(char **_ret); + +int reset_uid_gid(void); + +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) + +#define ETC_PASSWD_LOCK_PATH "/etc/.pwd.lock" + +static inline bool uid_is_dynamic(uid_t uid) { + return DYNAMIC_UID_MIN <= uid && uid <= DYNAMIC_UID_MAX; +} + +static inline bool gid_is_dynamic(gid_t gid) { + return uid_is_dynamic((uid_t) gid); +} + +static inline bool uid_is_system(uid_t uid) { + return uid <= SYSTEM_UID_MAX; +} + +static inline bool gid_is_system(gid_t gid) { + return gid <= SYSTEM_GID_MAX; +} + +/* 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; +} + +bool valid_user_group_name(const char *u); +bool valid_user_group_name_or_id(const char *u); +bool valid_gecos(const char *d); +bool valid_home(const char *p); + +static inline bool valid_shell(const char *p) { + /* We have the same requirements, so just piggy-back on the home check. + * + * Let's ignore /etc/shells because this is only applicable to real and + * not system users. It is also incompatible with the idea of empty /etc. + */ + return valid_home(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 |