d2i_SSL_SESSION, i2d_SSL_SESSION - convert SSL_SESSION
object from/to ASN1 representation
SSL_SESSION *d2i_SSL_SESSION(SSL_SESSION **a, unsigned
char **pp, long length);
int i2d_SSL_SESSION(SSL_SESSION *in, unsigned char **pp);
d2i_SSL_SESSION() transforms the external ASN1 representation
of an SSL/TLS session, stored as binary data at location
pp with length length, into an SSL_SESSION object.
i2d_SSL_SESSION() transforms the SSL_SESSION object in
into the ASN1 representation and stores it into the memory
location pointed to by pp. The length of the resulting
ASN1 representation is returned. If pp is the NULL
pointer, only the length is calculated and returned.
The SSL_SESSION object is built from several malloc()ed
parts, it can therefore not be moved, copied or stored
directly. In order to store session data on disk or into a
database, it must be transformed into a binary ASN1 representation.
When using d2i_SSL_SESSION(), the SSL_SESSION object is
automatically allocated. The reference count is 1, so that
the session must be explicitly removed using
SSL_SESSION_free(3), unless the SSL_SESSION object is completely
taken over, when being called inside the get_ses-
sion_cb() (see SSL_CTX_sess_set_get_cb(3)).
SSL_SESSION objects keep internal link information about
the session cache list, when being inserted into one
SSL_CTX object's session cache. One SSL_SESSION object,
regardless of its reference count, must therefore only be
used with one SSL_CTX object (and the SSL objects created
from this SSL_CTX object).
When using i2d_SSL_SESSION(), the memory location pointed
to by pp must be large enough to hold the binary representation
of the session. There is no known limit on the size
of the created ASN1 representation, so the necessary
amount of space should be obtained by first calling
i2d_SSL_SESSION() with pp=NULL, and obtain the size
needed, then allocate the memory and call i2d_SSL_SES-
d2i_SSL_SESSION() returns a pointer to the newly allocated
SSL_SESSION object. In case of failure the NULL-pointer is
returned and the error message can be retrieved from the
i2d_SSL_SESSION() returns the size of the ASN1 representation
in bytes. When the session is not valid, 0 is
returned and no operation is performed.
ssl(3), SSL_SESSION_free(3), SSL_CTX_sess_set_get_cb(3)
OpenBSD 3.6 2002-05-14 2 [ Back ]