typedef struct ossl_method_store_st OSSL_METHOD_STORE;
- OSSL_METHOD_STORE *ossl_method_store_new(void);
+ OSSL_METHOD_STORE *ossl_method_store_new(OPENSSL_CTX *ctx);
void ossl_method_store_free(OSSL_METHOD_STORE *store);
- int ossl_method_store_init(void);
- void ossl_method_store_cleanup(void);
+ int ossl_method_store_init(OPENSSL_CTX *ctx);
+ void ossl_method_store_cleanup(OPENSSL_CTX *ctx);
int ossl_method_store_add(OSSL_METHOD_STORE *store,
int nid, const char *properties,
void *method, void (*method_destruct)(void *));
=head2 Store Functions
-ossl_method_store_init() initialises the method store subsystem.
+ossl_method_store_init() initialises the method store subsystem in the scope of
+the library context B<ctx>.
ossl_method_store_cleanup() cleans up and shuts down the implementation method
-store subsystem.
+store subsystem in the scope of the library context B<ctx>.
-ossl_method_store_new() create a new empty method store.
+ossl_method_store_new() create a new empty method store using the supplied
+B<ctx> to allow access to the required underlying property data.
ossl_method_store_free() frees resources allocated to B<store>.
=head1 NAME
-openssl_ctx_new_index, openssl_ctx_get_data - internal OPENSSL_CTX routines
+openssl_ctx_get_data, openssl_ctx_run_once, openssl_ctx_onfree
+- internal OPENSSL_CTX routines
=head1 SYNOPSIS
#include "internal/cryptlib.h"
typedef struct openssl_ctx_method {
- void *(*new_func)(void);
+ void *(*new_func)(OPENSSL_CTX *ctx);
void (*free_func)(void *);
} OPENSSL_CTX_METHOD;
- int openssl_ctx_new_index(const OPENSSL_CTX_METHOD *meth);
- void *openssl_ctx_get_data(OPENSSL_CTX *ctx, int index);
+ void *openssl_ctx_get_data(OPENSSL_CTX *ctx, int index,
+ const OPENSSL_CTX_METHOD *meth);
+
+ int openssl_ctx_run_once(OPENSSL_CTX *ctx, unsigned int idx,
+ openssl_ctx_run_once_fn run_once_fn);
+ int openssl_ctx_onfree(OPENSSL_CTX *ctx, openssl_ctx_onfree_fn onfreefn);
=head1 DESCRIPTION
as a C<CRYPTO_EX_DATA>, which allows data from diverse parts of the
library to be added and removed dynamically.
Each such data item must have a corresponding CRYPTO_EX_DATA index
-associated with it.
+associated with it. Unlike normal CRYPTO_EX_DATA objects we use static indexes
+to identify data items. These are mapped transparetnly to CRYPTO_EX_DATA dynamic
+indexes internally to the implementation.
See the example further down to see how that's done.
-openssl_ctx_new_index() allocates a new library context index, and
-associates it with the functions given through C<meth>.
-The functions given through that method are used to create or free
-items that are stored at that index whenever a library context is
-created or freed, meaning that the code that use a data item of that
+openssl_ctx_get_data() is used to retrieve a pointer to the data in
+the library context C<ctx> associated with the given C<index>. An
+OPENSSL_CTX_METHOD must be defined and given in the C<meth> parameter. The index
+for it should be defined in cryptlib.h. The functions through the method are
+used to create or free items that are stored at that index whenever a library
+context is created or freed, meaning that the code that use a data item of that
index doesn't have to worry about that, just use the data available.
Deallocation of an index happens automatically when the library
context is freed.
-openssl_ctx_get_data() is used to retrieve a pointer to the data in
-the library context C<ctx> associated with the given C<index>.
+openssl_ctx_run_once is used to run some initialisation routine C<run_once_fn>
+exactly once per library context C<ctx> object. Each initialisation routine
+should be allocate a unique run once index in cryptlib.h.
-=head1 RETURN VALUES
+Any resources allocated via a run once initialisation routine can be cleaned up
+using openssl_ctx_onfree. This associates an "on free" routine C<onfreefn> with
+the library context C<ctx>. When C<ctx> is freed all associated "on free"
+routines are called.
-openssl_ctx_new_index() returns -1 on error, otherwise the allocated
-index number.
+=head1 RETURN VALUES
openssl_ctx_get_data() returns a pointer on success, or C<NULL> on
failure.
For a type C<FOO> that should end up in the OpenSSL library context, a
small bit of initialization is needed, i.e. to associate a constructor
-and a destructor to a new index.
-
- /* The index will always be entirely global, and dynamically allocated */
- static int foo_index = -1;
+and a destructor to an index.
typedef struct foo_st {
int i;
void *data;
} FOO;
- static void *foo_new(void)
+ static void *foo_new(OPENSSL_CTX *ctx)
{
FOO *ptr = OPENSSL_zalloc(sizeof(*foo));
if (ptr != NULL)
{
OPENSSL_free(ptr);
}
- static const OPENSSL_CTX_METHOD foo_method = {
+
+ /*
+ * Include a reference to this in the methods table in context.c
+ * OPENSSL_CTX_FOO_INDEX should be added to internal/cryptlib.h
+ */
+ const OPENSSL_CTX_METHOD foo_method = {
foo_new,
foo_free
};
- static int foo_init(void)
- {
- foo_index = openssl_ctx_new_index(foo_method);
-
- return foo_index != -1;
- }
-
=head2 Usage
To get and use the data stored in the library context, simply do this:
/*
* ctx is received from a caller,
- * foo_index comes from the example above
*/
- FOO *data = openssl_ctx_get_data(ctx, foo_index);
+ FOO *data = openssl_ctx_get_data(ctx, OPENSSL_CTX_FOO_INDEX, &foo_method);
+
+=head2 Run Once
+
+ void foo_cleanup(OPENSSL_CTX *ctx)
+ {
+ /* Free foo resources associated with ctx */
+ }
+
+ static openssl_ctx_run_once_fn do_foo_init;
+ static int do_foo_init(OPENSSL_CTX *ctx)
+ {
+ /* Allocate and initialise some foo resources and associated with ctx */
+ return openssl_ctx_onfree(ctx, &foo_cleanup)
+ }
+
+ int foo_some_function(OPENSSL_CTX *ctx)
+ {
+ if (!openssl_ctx_run_once(ctx,
+ OPENSSL_CTX_FOO_RUN_ONCE_INDEX,
+ do_foo_init))
+ return 0;
+
+ /* Do some work using foo resources in ctx */
+ }
+
=head1 SEE ALSO