/*
* ID Mapping Plugin interface for cifs-utils
* Copyright (C) 2012 Jeff Layton (jlayton@samba.org)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see .
*/
#include
#include
#ifndef _CIFSIDMAP_H
#define _CIFSIDMAP_H
#define NUM_AUTHS (6) /* number of authority fields */
#define SID_MAX_SUB_AUTHORITIES (15) /* max number of sub authority fields */
/*
* Binary representation of a SID as presented to/from the kernel. Note that
* the sub_auth field is always stored in little-endian here.
*/
struct cifs_sid {
uint8_t revision; /* revision level */
uint8_t num_subauth;
uint8_t authority[NUM_AUTHS];
uint32_t sub_auth[SID_MAX_SUB_AUTHORITIES];
} __attribute__((packed));
/*
* The type of the ID stored within cifs_uxid. UNKNOWN generally means that
* the mapping failed for some reason. BOTH means that the ID is usable as
* either a UID or a GID -- IOW, the UID and GID namespaces are unity-mapped.
*/
#define CIFS_UXID_TYPE_UNKNOWN (0) /* mapping type is unknown */
#define CIFS_UXID_TYPE_UID (1) /* mapping is a UID */
#define CIFS_UXID_TYPE_GID (2) /* mapping is a GID */
#define CIFS_UXID_TYPE_BOTH (3) /* usable as UID or GID */
/* This struct represents a uid or gid and its type */
struct cifs_uxid {
union {
uid_t uid;
gid_t gid;
} id;
unsigned char type;
} __attribute__((packed));
/*
* Plugins should implement the following functions:
*/
/**
* cifs_idmap_init_plugin - Initialize the plugin interface
* @handle - return pointer for an opaque handle
* @errmsg - pointer to error message pointer
*
* This function should do whatever is required to establish a context
* for later ID mapping operations. The "handle" is an opaque context
* cookie that will be passed in on subsequent ID mapping operations.
* The errmsg is used to pass back an error string both during the init
* and in subsequent idmapping functions. On any error, the plugin
* should point *errmsg at a string describing that error. Returns 0
* on success and non-zero on error.
*/
extern int cifs_idmap_init_plugin(void **handle, const char **errmsg);
/**
* cifs_idmap_exit_plugin - Destroy an idmapping context
* @handle - context handle that should be destroyed
*
* When programs are finished with the idmapping plugin, they'll call
* this function to destroy any context that was created during the
* init_plugin. The handle passed back in was the one given by the init
* routine.
*/
extern void cifs_idmap_exit_plugin(void *handle);
/**
* cifs_idmap_sid_to_str - convert cifs_sid to a string
* @handle - context handle
* @sid - pointer to a cifs_sid
* @name - return pointer for the name
*
* This function should convert the given cifs_sid to a string
* representation or mapped name in a heap-allocated buffer. The caller
* of this function is expected to free "name" on success. Returns 0 on
* success and non-zero on error. On error, the errmsg pointer passed
* in to the init_plugin function should point to an error string. The
* caller will not free the error string.
*/
extern int cifs_idmap_sid_to_str(void *handle, const struct cifs_sid *sid,
char **name);
/**
* cifs_idmap_str_to_sid - convert string to struct cifs_sid
* @handle - context handle
* @name - pointer to name string to be converted
* @sid - pointer to struct cifs_sid where result should go
*
* This function converts a name string or string representation of
* a SID to a struct cifs_sid. The cifs_sid should already be
* allocated. Returns 0 on success and non-zero on error. On error, the
* plugin should reset the errmsg pointer passed to the init_plugin
* function to an error string. The caller will not free the error string.
*/
extern int cifs_idmap_str_to_sid(void *handle, const char *name,
struct cifs_sid *sid);
/**
* cifs_idmap_sids_to_ids - convert struct cifs_sids to struct cifs_uxids
* @handle - context handle
* @sid - pointer to array of struct cifs_sids to be converted
* @num - number of sids to be converted
* @cuxid - pointer to preallocated array of struct cifs_uxids for return
*
* This function should map an array of struct cifs_sids to an array of
* struct cifs_uxids.
*
* Returns 0 if at least one conversion was successful and non-zero on error.
* Any that were not successfully converted will have a cuxid->type of
* CIFS_UXID_TYPE_UNKNOWN.
*
* On any error, the plugin should reset the errmsg pointer passed to the
* init_plugin function to an error string. The caller will not free the error
* string.
*/
extern int cifs_idmap_sids_to_ids(void *handle, const struct cifs_sid *sid,
const size_t num, struct cifs_uxid *cuxid);
/**
* cifs_idmap_ids_to_sids - convert uid to struct cifs_sid
* @handle - context handle
* @cuxid - pointer to array of struct cifs_uxid to be converted to SIDs
* @num - number of cifs_uxids to be converted to SIDs
* @sid - pointer to preallocated array of struct cifs_sid where results
* should be stored
*
* This function should map an array of cifs_uxids an array of struct cifs_sids.
* Returns 0 if at least one conversion was successful and non-zero on error.
* Any sids that were not successfully converted should have their revision
* number set to 0.
*
* On any error, the plugin should reset the errmsg pointer passed to the
* init_plugin function to an error string. The caller will not free the error
* string.
*/
extern int cifs_idmap_ids_to_sids(void *handle, const struct cifs_uxid *cuxid,
const size_t num, struct cifs_sid *sid);
#endif /* _CIFSIDMAP_H */