d2i_SSL_SESSION.pod revision 89837
1=pod 2 3=head1 NAME 4 5d2i_SSL_SESSION, i2d_SSL_SESSION - convert SSL_SESSION object from/to ASN1 representation 6 7=head1 SYNOPSIS 8 9 #include <openssl/ssl.h> 10 11 SSL_SESSION *d2i_SSL_SESSION(SSL_SESSION **a, unsigned char **pp, long length); 12 int i2d_SSL_SESSION(SSL_SESSION *in, unsigned char **pp); 13 14=head1 DESCRIPTION 15 16d2i_SSL_SESSION() transforms the external ASN1 representation of an SSL/TLS 17session, stored as binary data at location B<pp> with length B<length>, into 18an SSL_SESSION object. 19 20i2d_SSL_SESSION() transforms the SSL_SESSION object B<in> into the ASN1 21representation and stores it into the memory location pointed to by B<pp>. 22The length of the resulting ASN1 representation is returned. If B<pp> is 23the NULL pointer, only the length is calculated and returned. 24 25=head1 NOTES 26 27The SSL_SESSION object is built from several malloc()ed parts, it can 28therefore not be moved, copied or stored directly. In order to store 29session data on disk or into a database, it must be transformed into 30a binary ASN1 representation. 31 32When using d2i_SSL_SESSION(), the SSL_SESSION object is automatically 33allocated. The reference count is 1, so that the session must be 34explicitly removed using L<SSL_SESSION_free(3)|SSL_SESSION_free(3)>, 35unless the SSL_SESSION object is completely taken over, when being called 36inside the get_session_cb() (see 37L<SSL_CTX_sess_set_get_cb(3)|SSL_CTX_sess_set_get_cb(3)>). 38 39SSL_SESSION objects keep internal link information about the session cache 40list, when being inserted into one SSL_CTX object's session cache. 41One SSL_SESSION object, regardless of its reference count, must therefore 42only be used with one SSL_CTX object (and the SSL objects created 43from this SSL_CTX object). 44 45When using i2d_SSL_SESSION(), the memory location pointed to by B<pp> must be 46large enough to hold the binary representation of the session. There is no 47known limit on the size of the created ASN1 representation, so the necessary 48amount of space should be obtained by first calling i2d_SSL_SESSION() with 49B<pp=NULL>, and obtain the size needed, then allocate the memory and 50call i2d_SSL_SESSION() again. 51 52=head1 RETURN VALUES 53 54d2i_SSL_SESSION() returns a pointer to the newly allocated SSL_SESSION 55object. In case of failure the NULL-pointer is returned and the error message 56can be retrieved from the error stack. 57 58i2d_SSL_SESSION() returns the size of the ASN1 representation in bytes. 59When the session is not valid, B<0> is returned and no operation is performed. 60 61=head1 SEE ALSO 62 63L<ssl(3)|ssl(3)>, L<SSL_SESSION_free(3)|SSL_SESSION_free(3)>, 64L<SSL_CTX_sess_set_get_cb(3)|SSL_CTX_sess_set_get_cb(3)> 65 66=cut 67