382 lines
17 KiB
C
382 lines
17 KiB
C
|
|
||
|
/*
|
||
|
|
||
|
Arbitrary Attribute Interchange Protocol , AAIP version 0.2
|
||
|
Demonstration program for encoding and decoding EA and ACL.
|
||
|
|
||
|
See http://libburnia-project.org/wiki/AAIP
|
||
|
or doc/susp_aaip_0_2.txt
|
||
|
|
||
|
test/aaip_0.2.h - Public declarations
|
||
|
|
||
|
*/
|
||
|
|
||
|
#ifndef Aaip_h_is_includeD
|
||
|
#define Aaip_h_is_includeD yes
|
||
|
|
||
|
|
||
|
/* --------------------------------- Encoder ---------------------------- */
|
||
|
|
||
|
/* Convert an array of Arbitrary Attributes into a series of AAIP fields.
|
||
|
@param aa_name The 2 byte SUSP Signature Word of the fields
|
||
|
@param num_attrs Number of attributes
|
||
|
@param names Array of pointers to 0 terminated name strings
|
||
|
@param value_lengths Array of byte lengths for each value
|
||
|
@param values Array of pointers to the value bytes
|
||
|
@param result_len Number of bytes in the resulting SUSP field string
|
||
|
@param result *result will point to the start of the result string.
|
||
|
This is malloc() memory which needs to be freed when
|
||
|
no longer needed
|
||
|
@param flag Bitfield for control purposes
|
||
|
bit0= set CONTINUE bit of last AA field to 1
|
||
|
@return >0 is the number of SUSP fields generated,
|
||
|
0 means error
|
||
|
*/
|
||
|
unsigned int aaip_encode(char aa_name[2],
|
||
|
unsigned int num_attrs, char **names,
|
||
|
size_t *value_lengths, char **values,
|
||
|
size_t *result_len, unsigned char **result, int flag);
|
||
|
|
||
|
|
||
|
/* ------ ACL representation ------ */
|
||
|
|
||
|
/* Convert an ACL from long text form into the value of an Arbitrary
|
||
|
Attribute. According to AAIP 0.2 this value is to be stored together with
|
||
|
an empty name.
|
||
|
@param acl_text The ACL in long text form
|
||
|
@param result_len Number of bytes in the resulting value
|
||
|
@param result *result will point to the start of the result string.
|
||
|
This is malloc() memory which needs to be freed when
|
||
|
no longer needed
|
||
|
@param flag Bitfield for control purposes
|
||
|
bit0= count only
|
||
|
bit1= use numeric qualifiers rather than names
|
||
|
@return >0 means ok
|
||
|
0 means error
|
||
|
*/
|
||
|
int aaip_encode_acl(char *acl_text,
|
||
|
size_t *result_len, unsigned char **result, int flag);
|
||
|
|
||
|
|
||
|
/* ------ OS interface ------ */
|
||
|
|
||
|
/* Obtain the ACL of the given file in long text form.
|
||
|
@param path Path to the file
|
||
|
@param text Will hold the result. This is a managed object which
|
||
|
finally has to be freed by a call to this function
|
||
|
with bit15 of flag.
|
||
|
@param flag Bitfield for control purposes
|
||
|
bit0= obtain default ACL rather than access ACL
|
||
|
bit15= free text and return 1
|
||
|
@return > 0 ok
|
||
|
-1 failure of system ACL service (see errno)
|
||
|
*/
|
||
|
int aaip_get_acl_text(char *path, char **text, int flag);
|
||
|
|
||
|
|
||
|
/* Obtain the Extended Attributes and/or the ACLs of the given file in a form
|
||
|
that is ready for aaip_encode(). The returned data objects finally have
|
||
|
to be freed by a call with flag bit 15.
|
||
|
@param path Path to the file
|
||
|
@param num_attrs Will return the number of name-value pairs
|
||
|
@param names Will return an array of pointers to 0-terminated names
|
||
|
@param value_lengths Will return an arry with the lenghts of values
|
||
|
@param values Will return an array of pointers to 8-bit values
|
||
|
@param flag Bitfield for control purposes
|
||
|
bit0= obtain ACLs (access and eventually default) via
|
||
|
system ACL API and encode
|
||
|
bit1= use numeric ACL qualifiers rather than names
|
||
|
bit2= do not obtain attributes other than ACLs
|
||
|
bit3= do not ignore eventual ACL attribute
|
||
|
(e.g. system.posix_acl_access)
|
||
|
bit15= free memory of names, value_lengths, values
|
||
|
@return >0 ok
|
||
|
<=0 error
|
||
|
*/
|
||
|
int aaip_get_attr_list(char *path, size_t *num_attrs, char ***names,
|
||
|
size_t **value_lengths, char ***values, int flag);
|
||
|
|
||
|
|
||
|
/* --------------------------------- Decoder ---------------------------- */
|
||
|
|
||
|
/*
|
||
|
The AAIP decoder offers several levels of abstraction of which the
|
||
|
lower two avoid the use of dynamic memory. It provides a stateful decoding
|
||
|
context with a small buffer which delivers results to caller provided
|
||
|
memory locations.
|
||
|
|
||
|
The lowest level is the stream-like Component Level Interface. It allows
|
||
|
to decode very many very long attributes.
|
||
|
|
||
|
Next is the Pair Level Interface which delivers to fixly sized storage for
|
||
|
name and value. It allows to decode very many attributes.
|
||
|
|
||
|
The List Level Interface uses dynamic memory allocation to provide arrays
|
||
|
of names, values and value lengths. It is intended for moderately sized
|
||
|
attribute lists but may also be used as alternative to Pair Level.
|
||
|
*/
|
||
|
|
||
|
|
||
|
/* The AAIP decoder context.
|
||
|
*/
|
||
|
struct aaip_state;
|
||
|
|
||
|
|
||
|
/* Obtain the size in bytes of an aaip_state object.
|
||
|
*/
|
||
|
size_t aaip_sizeof_aaip_state(void);
|
||
|
|
||
|
|
||
|
/* Initialize a AAIP decoder context.
|
||
|
This has to be done before the first AA field of a node is processed.
|
||
|
The caller has to provide the storage of the struct aaip_state.
|
||
|
@param aaip The AAIP decoder context to be initialized
|
||
|
@param aa_name The Signature Word (advised is "AA")
|
||
|
@param flag Bitfield for control purposes
|
||
|
submit 0
|
||
|
@return <=0 error , >0 ok
|
||
|
*/
|
||
|
int aaip_init_aaip_state(struct aaip_state *aaip, char aa_name[2], int flag);
|
||
|
|
||
|
|
||
|
/* ------------------------- Component Level Interface ------------------- */
|
||
|
/*
|
||
|
Provides support for unlimited component size but demands the caller
|
||
|
to have a growing storage facility resp. to do own oversize handling.
|
||
|
|
||
|
This interface expects moderatly sized input pieces and will hand out
|
||
|
moderately sized result pieces. The number of transactions is virtually
|
||
|
unlimited.
|
||
|
*/
|
||
|
|
||
|
/* Submit small data chunk for decoding.
|
||
|
The return value will tell whether data are pending for being fetched.
|
||
|
@param aaip The AAIP decoder context
|
||
|
@param data Not more than 2048 bytes input for the decoder
|
||
|
@param num_data Number of bytes in data
|
||
|
0 inquires the buffer status avoiding replies <= 0
|
||
|
@param ready_bytes Number of decoded bytes ready for delivery
|
||
|
@param flag Bitfield for control purposes
|
||
|
@return -1= non-AA field detected
|
||
|
*ready_bytes gives number of consumed bytes in data
|
||
|
0= cannot accept data because buffer full
|
||
|
1= no component record complete, submit more data
|
||
|
2= component record complete, may be delivered
|
||
|
3= component complete, may be delivered
|
||
|
4= no component available, no more data expected, done
|
||
|
*/
|
||
|
int aaip_submit_data(struct aaip_state *aaip,
|
||
|
unsigned char *data, size_t num_data,
|
||
|
size_t *ready_bytes, int flag);
|
||
|
|
||
|
|
||
|
/* Fetch the available part of current component.
|
||
|
The return value will tell whether it belongs to name or to value and
|
||
|
whether that name or value is completed now.
|
||
|
@param aaip The AAIP decoder context
|
||
|
@param result Has to point to storage for the component data
|
||
|
@param result_size Gives the amount of provided result storage
|
||
|
@param num_result Will tell the number of fetched result bytes
|
||
|
@param flag Bitfield for control purposes
|
||
|
bit0= discard data rather than copying to result
|
||
|
@return -2 = insufficient result_size
|
||
|
-1 = no data ready for delivery
|
||
|
0 = result holds the final part of a name
|
||
|
1 = result holds an intermediate part of a name
|
||
|
2 = result holds the final part of a value
|
||
|
3 = result holds an intermediate part of a value
|
||
|
*/
|
||
|
int aaip_fetch_data(struct aaip_state *aaip,
|
||
|
char *result, size_t result_size, size_t *num_result,
|
||
|
int flag);
|
||
|
|
||
|
|
||
|
/* Skip the current component and eventually the following value component.
|
||
|
This has to be called if fetching of a component shall be aborted
|
||
|
but the next component resp. pair shall be fetchable again.
|
||
|
aaip_submit_data() will not indicate readiness for fetching until all
|
||
|
bytes of the skipped components are submitted. Those bytes get discarded.
|
||
|
@param aaip The AAIP decoder context
|
||
|
@param flag Bitfield for control purposes
|
||
|
bit0= do not skip value if current component is name
|
||
|
@return <=0 error , 1= now in skip state, 2= not in skip state
|
||
|
*/
|
||
|
int aaip_skip_component(struct aaip_state *aaip, int flag);
|
||
|
|
||
|
|
||
|
/* ------------------------- Pair Level Interface ------------------------ */
|
||
|
/*
|
||
|
Provides support for names and values of limited size. The limits are
|
||
|
given by the caller who has to provide the storage for name and value.
|
||
|
|
||
|
This interface expects moderatly sized input pieces.
|
||
|
The number of input transcations is virtually unlimited.
|
||
|
The number of pair transactions after aaip_init() should be limited
|
||
|
to 4 billion.
|
||
|
*/
|
||
|
|
||
|
|
||
|
/* Accept raw input data and collect a pair of name and value.
|
||
|
The return value will indicate whether the pair is complete, whether more
|
||
|
pairs are complete or whether more data are desired. No input data will be
|
||
|
accepted as long as complete pairs are pending. The end of the attribute
|
||
|
list will be indicated.
|
||
|
@param aaip The AAIP decoder context
|
||
|
@param data The raw data to decode
|
||
|
@param num_data Number of data bytes provided
|
||
|
@param consumed Returns the number of consumed data bytes
|
||
|
@param name Buffer to build the name string
|
||
|
@param name_size Maximum number of bytes in name
|
||
|
@param name_fill Holds the current buffer fill of name
|
||
|
@param value Buffer to build the value string
|
||
|
@param value_size Maximum number of bytes in value
|
||
|
@param value_fill Holds the current buffer fill of value
|
||
|
@param flag Bitfield for control purposes - submit 0 for now
|
||
|
@return <0 error
|
||
|
0 data not accepted, first fetch pending pairs with num_data == 0
|
||
|
1 name and value are not valid yet, submit more data
|
||
|
2 name and value are valid, submit more data
|
||
|
3 name and value are valid, pairs pending, fetch with num_data == 0
|
||
|
4 name and value are valid, no more data expected
|
||
|
5 name and value are not valid, no more data expected
|
||
|
|
||
|
*/
|
||
|
int aaip_decode_pair(struct aaip_state *aaip,
|
||
|
unsigned char *data, size_t num_data, size_t *consumed,
|
||
|
char *name, size_t name_size, size_t *name_fill,
|
||
|
char *value, size_t value_size, size_t *value_fill,
|
||
|
int flag);
|
||
|
|
||
|
|
||
|
/* Inquire the number of pairs which were skipped because being oversized.
|
||
|
@param aaip The AAIP decoder context
|
||
|
@param flag Bitfield for control purposes - submit 0 for now
|
||
|
@return The number of pairs skipped since aaip_init()
|
||
|
*/
|
||
|
unsigned int aaip_get_pairs_skipped(struct aaip_state *aaip, int flag);
|
||
|
|
||
|
|
||
|
/* ------------------------- List Level Interface ------------------------ */
|
||
|
/*
|
||
|
Provides support for names and values of limited size. The limits are
|
||
|
given for total memory consumption and for number of attributes.
|
||
|
|
||
|
Iterated decoding is supported as long as no single attribute exceeds
|
||
|
the memory limit.
|
||
|
*/
|
||
|
|
||
|
/* Accept raw input data and collect arrays of name pointers, value lengths
|
||
|
and value pointers. A handle object will emerge which finally has to be
|
||
|
be freed by a call with bit 15.
|
||
|
@param handle The decoding context.
|
||
|
It will be created by this call with flag bit 0 or if
|
||
|
*handle == NULL. This handle has to be the same as long
|
||
|
as decoding goes on and finally has to be freed by a
|
||
|
call with bit15.
|
||
|
@param aa_name The Signature Word (advised is "AA")
|
||
|
@param memory_limit Maximum number of bytes to allocate
|
||
|
@param num_attr_limit Maximum number of name-value pairs to allocate
|
||
|
@param data The raw data to decode
|
||
|
@param num_data Number of data bytes provided
|
||
|
@param consumed Returns the number of consumed data bytes
|
||
|
@param flag Bitfield for control purposes
|
||
|
bit0= this is the first call for a file object
|
||
|
bit15= end decoding :
|
||
|
Free handle and its intermediate list memory.
|
||
|
@return <=0 error
|
||
|
1 not complete yet, submit more data
|
||
|
2 arrays are complete, call aaip_get_decoded_attrs()
|
||
|
3 limit exceeded, not complete yet, call with bit15 and give up
|
||
|
4 limit exceeded, call aaip_get_decoded_attrs() and try again
|
||
|
*/
|
||
|
int aaip_decode_attrs(struct aaip_state **handle, char aa_name[2],
|
||
|
size_t memory_limit, size_t num_attr_limit,
|
||
|
unsigned char *data, size_t num_data, size_t *consumed,
|
||
|
int flag);
|
||
|
|
||
|
|
||
|
/* Obtain the resulting attributes when aaip_decode_attrs() indicates to
|
||
|
be done or to have the maximum possible amount of result ready.
|
||
|
The returned data objects get detached from handle making it ready for
|
||
|
the next round of decoding with possibly a different input source. The
|
||
|
returned data objects finally have to be freed by a call with flag bit 15.
|
||
|
@param handle The decoding context created by aaip_decode_attrs()
|
||
|
@param num_attrs Will return the number of name-value pairs
|
||
|
@param names Will return an array of pointers to 0-terminated names
|
||
|
@param value_lengths Will return an arry with the lenghts of values
|
||
|
@param values Will return an array of pointers to 8-bit values
|
||
|
@param flag Bitfield for control purposes
|
||
|
bit15= free memory of names, value_lengths, values
|
||
|
*/
|
||
|
int aaip_get_decoded_attrs(struct aaip_state **handle, size_t *num_attrs,
|
||
|
char ***names, size_t **value_lengths, char ***values,
|
||
|
int flag);
|
||
|
|
||
|
|
||
|
/* ------ ACL representation ------ */
|
||
|
|
||
|
/* Convert an AAIP 0.2 ACL attribute value into the long text form of ACL.
|
||
|
@param data The raw data to decode
|
||
|
@param num_data Number of data bytes provided
|
||
|
@param consumed Returns the number of consumed data bytes
|
||
|
@param acl_text Will be filled with ACL long text form
|
||
|
@param acl_text_size Maximum number of bytes to be written to acl_text
|
||
|
@param acl_text_fill Will return the number of bytes in acl_text
|
||
|
@param flag Bitfield for control purposes
|
||
|
bit0= count only, do not really produce bytes:
|
||
|
acl_text will not be touched,
|
||
|
acl_text_size will be ignored,
|
||
|
*acl_text_fill will return the counted number
|
||
|
bit1= expected is a default ACL (see return value 2)
|
||
|
@return 1 success
|
||
|
2 success, begin of default/access ACL encountered,
|
||
|
submit data + *consumed for access/default ACL
|
||
|
-1 error with reading of qualifier
|
||
|
-2 error with writing of ACL text line
|
||
|
-3 version mismatch
|
||
|
-4 unknown tag type encountered
|
||
|
*/
|
||
|
int aaip_decode_acl(unsigned char *data, size_t num_data, size_t *consumed,
|
||
|
char *acl_text, size_t acl_text_size,
|
||
|
size_t *acl_text_fill, int flag);
|
||
|
|
||
|
|
||
|
/* ------ OS interface ------ */
|
||
|
|
||
|
/* Set the ACL of the given file to a given list in long text form.
|
||
|
@param path Path to the file
|
||
|
@param text The input text (0 terminated, ACL long text form)
|
||
|
@param flag Bitfield for control purposes
|
||
|
bit0= set default ACL rather than access ACL
|
||
|
@return > 0 ok
|
||
|
-1 failure of system ACL service (see errno)
|
||
|
*/
|
||
|
int aaip_set_acl_text(char *path, char *text, int flag);
|
||
|
|
||
|
|
||
|
/* Bring the given attributes and/or ACLs into effect with the given file.
|
||
|
@param path Path to the file
|
||
|
@param num_attrs Number of attributes
|
||
|
@param names Array of pointers to 0 terminated name strings
|
||
|
@param value_lengths Array of byte lengths for each attribute payload
|
||
|
@param values Array of pointers to the attribute payload bytes
|
||
|
@param flag Bitfield for control purposes
|
||
|
bit0= decode and set ACLs
|
||
|
bit1= first clear all existing attributes of the file
|
||
|
bit2= do not set attributes other than ACLs
|
||
|
bit3= do not ignore eventual ACL attribute
|
||
|
(e.g. system.posix_acl_access)
|
||
|
@return 1 success
|
||
|
-1 error memory allocation
|
||
|
-2 error with decoding of ACL
|
||
|
-3 error with setting ACL
|
||
|
-4 error with setting attribute
|
||
|
-5 error with deleting attributes
|
||
|
|
||
|
*/
|
||
|
int aaip_set_attr_list(char *path, size_t num_attrs, char **names,
|
||
|
size_t *value_lengths, char **values, int flag);
|
||
|
|
||
|
#endif /* ! Aaip_h_is_includeD */
|
||
|
|