OBER_GET_STRING(3) FreeBSD Library Functions Manual OBER_GET_STRING(3)
NAME
ober_get_null, ober_get_eoc, ober_get_integer, ober_get_enumerated,
ober_get_boolean, ober_get_string, ober_get_nstring, ober_get_ostring,
ober_get_bitstring, ober_get_oid, ober_getpos, ober_scanf_elements -
access properties of ASN.1 objects decoded from BER
SYNOPSIS
#include <sys/types.h>
#include <ber.h>
int
ober_get_null(struct ber_element *root);
int
ober_get_eoc(struct ber_element *root);
int
ober_get_integer(struct ber_element *root, long long *val);
int
ober_get_enumerated(struct ber_element *root, long long *val);
int
ober_get_boolean(struct ber_element *root, int *bool);
int
ober_get_string(struct ber_element *root, char **charbuf);
int
ober_get_nstring(struct ber_element *root, void **buf, size_t *size);
int
ober_get_ostring(struct ber_element *root,
struct ber_octetstring *ostring);
int
ober_get_bitstring(struct ber_element *root, void **buf, size_t *size);
int
ober_get_oid(struct ber_element *root, struct ber_oid *oid);
off_t
ober_getpos(struct ber_element *elm);
int
ober_scanf_elements(struct ber_element *root, char *format, ...);
DESCRIPTION
Functions which take two arguments save the value contained in the root
element into the storage location pointed to by the second argument. If
the storage location is NULL then only a type check is performed.
Additionally, ober_get_nstring() and ober_get_bitstring() save the number
of bytes contained in the string into *size. If buf is NULL and size is
not NULL, size is set. size must not be NULL to return a valid buf.
ober_scanf_elements() retrieves the values from zero or more elements
starting at root. For each character in fmt, arguments of the types
given in the following table are consumed and passed to the function
listed, processing one ber_element per character. The following
characters are valid:
character function arguments
$ see below 0
B ober_get_bitstring() 2: void **, size_t *
b ober_get_boolean() 1: int *
d ober_get_integer() 1: int *
E ober_get_enumerated() 1: long long *
e see below 1: struct ber_element **
i ober_get_integer() 1: long long *
o ober_get_oid() 1: struct ber_oid *
p ober_getpos() 1: off_t *
S see below 0
s ober_get_string() 1: char **
t see below 2: int *, unsigned int *
x ober_get_nstring() 2: void **, size_t *
( or { see below 0
) or } see below 0
. ober_get_eoc() 0
0 ober_get_null() 0
For `e', `p', `S', and `t', the type of the element is not checked. For
`p' and `t', the pointer is not incremented to the next element. For
`e', a pointer to the element is stored in the corresponding pointer
variable. For `S', the element is skipped without extracting any
information from it. For `t', the class and type of the element are
stored in the two corresponding variables, but if the element contains a
value, that value is ignored. A `$' mandates the end of a sequence or
set.
For an opening parenthesis or brace, it is checked that the element is a
sequence or a set, and parsing continues with its children. For a
closing parenthesis or brace, parsing of the current sequence or set is
ended and parsing continues with the element following the sequence or
set.
RETURN VALUES
ober_getpos() returns the value of be_offs.
ober_scanf_elements() returns 0 for success or -1 when encountering
elements that do not agree with the expectations of fmt or when fmt is
syntactically invalid. Even when ober_scanf_elements() fails, some of
the arguments may already have been filled in.
The other functions return 0 if root is of the requested type or -1
otherwise.
SEE ALSO
ober_add_string(3), ober_oid_cmp(3), ober_read_elements(3),
ober_set_header(3)
STANDARDS
ITU-T Recommendation X.690, also known as ISO/IEC 8825-1: Information
technology - ASN.1 encoding rules.
HISTORY
These functions first appeared as internal functions in snmpd(8) in
OpenBSD 4.2 and were moved to libutil in OpenBSD 6.6.
AUTHORS
The BER library was written by Claudio Jeker <
[email protected]>, Marc
Balmer <
[email protected]> and Reyk Floeter <
[email protected]>.
FreeBSD 14.1-RELEASE-p8 March 31, 2021 FreeBSD 14.1-RELEASE-p8