]> git.ipfire.org Git - thirdparty/openssl.git/blame - doc/crypto/BN_new.pod
Fix L<> content in manpages
[thirdparty/openssl.git] / doc / crypto / BN_new.pod
CommitLineData
dd8dec69
UM
1=pod
2
3=head1 NAME
4
5BN_new, BN_init, BN_clear, BN_free, BN_clear_free - allocate and free BIGNUMs
6
7=head1 SYNOPSIS
8
9 #include <openssl/bn.h>
10
11 BIGNUM *BN_new(void);
12
dd8dec69
UM
13 void BN_clear(BIGNUM *a);
14
15 void BN_free(BIGNUM *a);
16
17 void BN_clear_free(BIGNUM *a);
18
19=head1 DESCRIPTION
20
e35af275 21BN_new() allocates and initializes a B<BIGNUM> structure.
dd8dec69
UM
22
23BN_clear() is used to destroy sensitive data such as keys when they
24are no longer needed. It erases the memory used by B<a> and sets it
25to the value 0.
26
27BN_free() frees the components of the B<BIGNUM>, and if it was created
28by BN_new(), also the structure itself. BN_clear_free() additionally
29overwrites the data before the memory is returned to the system.
23a1d5e9 30If B<a> is NULL, nothing is done.
dd8dec69
UM
31
32=head1 RETURN VALUES
33
34BN_new() returns a pointer to the B<BIGNUM>. If the allocation fails,
35it returns B<NULL> and sets an error code that can be obtained
9b86974e 36by L<ERR_get_error(3)>.
dd8dec69 37
e35af275
MC
38BN_clear(), BN_free() and BN_clear_free() have no return values.
39
40=head1 REMOVED FUNCTIONALITY
41
42 void BN_init(BIGNUM *);
43
44BN_init() is no longer available as of OpenSSL 1.1.0. It was used to initialize
45an existing uninitialized B<BIGNUM>. Typically this would be done as follows:
46
47 BIGNUM a;
48 BN_init(&a);
49
50Applications should replace use of BN_init with BN_new instead:
51
52 BIGNUM *a;
53 a = BN_new();
54 if(!a) /* Handle error */
55 ...
56 BN_free(a);
dd8dec69
UM
57
58=head1 SEE ALSO
59
9b86974e 60L<bn(3)>, L<ERR_get_error(3)>
dd8dec69
UM
61
62=head1 HISTORY
63
e93f9a32 64BN_new(), BN_clear(), BN_free() and BN_clear_free() are available in
dd8dec69 65all versions on SSLeay and OpenSSL. BN_init() was added in SSLeay
e35af275 660.9.1b and removed in OpenSSL 1.1.0.
dd8dec69
UM
67
68=cut