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OSSL_PARAM_int(3)                   OpenSSL                  OSSL_PARAM_int(3)



NAME
       OSSL_PARAM_double, OSSL_PARAM_int, OSSL_PARAM_int32, OSSL_PARAM_int64,
       OSSL_PARAM_long, OSSL_PARAM_size_t, OSSL_PARAM_time_t, OSSL_PARAM_uint,
       OSSL_PARAM_uint32, OSSL_PARAM_uint64, OSSL_PARAM_ulong, OSSL_PARAM_BN,
       OSSL_PARAM_utf8_string, OSSL_PARAM_octet_string, OSSL_PARAM_utf8_ptr,
       OSSL_PARAM_octet_ptr, OSSL_PARAM_END, OSSL_PARAM_DEFN,
       OSSL_PARAM_construct_double, OSSL_PARAM_construct_int,
       OSSL_PARAM_construct_int32, OSSL_PARAM_construct_int64,
       OSSL_PARAM_construct_long, OSSL_PARAM_construct_size_t,
       OSSL_PARAM_construct_time_t, OSSL_PARAM_construct_uint,
       OSSL_PARAM_construct_uint32, OSSL_PARAM_construct_uint64,
       OSSL_PARAM_construct_ulong, OSSL_PARAM_construct_BN,
       OSSL_PARAM_construct_utf8_string, OSSL_PARAM_construct_utf8_ptr,
       OSSL_PARAM_construct_octet_string, OSSL_PARAM_construct_octet_ptr,
       OSSL_PARAM_construct_end, OSSL_PARAM_locate, OSSL_PARAM_locate_const,
       OSSL_PARAM_get_double, OSSL_PARAM_get_int, OSSL_PARAM_get_int32,
       OSSL_PARAM_get_int64, OSSL_PARAM_get_long, OSSL_PARAM_get_size_t,
       OSSL_PARAM_get_time_t, OSSL_PARAM_get_uint, OSSL_PARAM_get_uint32,
       OSSL_PARAM_get_uint64, OSSL_PARAM_get_ulong, OSSL_PARAM_get_BN,
       OSSL_PARAM_get_utf8_string, OSSL_PARAM_get_octet_string,
       OSSL_PARAM_get_utf8_ptr, OSSL_PARAM_get_octet_ptr,
       OSSL_PARAM_get_utf8_string_ptr, OSSL_PARAM_get_octet_string_ptr,
       OSSL_PARAM_set_double, OSSL_PARAM_set_int, OSSL_PARAM_set_int32,
       OSSL_PARAM_set_int64, OSSL_PARAM_set_long, OSSL_PARAM_set_size_t,
       OSSL_PARAM_set_time_t, OSSL_PARAM_set_uint, OSSL_PARAM_set_uint32,
       OSSL_PARAM_set_uint64, OSSL_PARAM_set_ulong, OSSL_PARAM_set_BN,
       OSSL_PARAM_set_utf8_string, OSSL_PARAM_set_octet_string,
       OSSL_PARAM_set_utf8_ptr, OSSL_PARAM_set_octet_ptr,
       OSSL_PARAM_UNMODIFIED, OSSL_PARAM_modified,
       OSSL_PARAM_set_all_unmodified - OSSL_PARAM helpers

LIBRARY
       libcrypto, -lcrypto

SYNOPSIS
        #include <openssl/params.h>

        /*
         * TYPE in function names is one of:
         * double, int, int32, int64, long, size_t, time_t, uint, uint32, uint64, ulong
         * Corresponding TYPE in function arguments is one of:
         * double, int, int32_t, int64_t, long, size_t, time_t, unsigned int, uint32_t,
         * uint64_t, unsigned long
         */

        #define OSSL_PARAM_TYPE(key, address)
        #define OSSL_PARAM_BN(key, address, size)
        #define OSSL_PARAM_utf8_string(key, address, size)
        #define OSSL_PARAM_octet_string(key, address, size)
        #define OSSL_PARAM_utf8_ptr(key, address, size)
        #define OSSL_PARAM_octet_ptr(key, address, size)
        #define OSSL_PARAM_END

        #define OSSL_PARAM_UNMODIFIED

        #define OSSL_PARAM_DEFN(key, type, addr, sz)    \
           { (key), (type), (addr), (sz), OSSL_PARAM_UNMODIFIED }

        OSSL_PARAM OSSL_PARAM_construct_TYPE(const char *key, TYPE *buf);
        OSSL_PARAM OSSL_PARAM_construct_BN(const char *key, unsigned char *buf,
                                           size_t bsize);
        OSSL_PARAM OSSL_PARAM_construct_utf8_string(const char *key, char *buf,
                                                    size_t bsize);
        OSSL_PARAM OSSL_PARAM_construct_octet_string(const char *key, void *buf,
                                                     size_t bsize);
        OSSL_PARAM OSSL_PARAM_construct_utf8_ptr(const char *key, char **buf,
                                                 size_t bsize);
        OSSL_PARAM OSSL_PARAM_construct_octet_ptr(const char *key, void **buf,
                                                  size_t bsize);
        OSSL_PARAM OSSL_PARAM_construct_end(void);

        OSSL_PARAM *OSSL_PARAM_locate(OSSL_PARAM *array, const char *key);
        const OSSL_PARAM *OSSL_PARAM_locate_const(const OSSL_PARAM *array,
                                                  const char *key);

        int OSSL_PARAM_get_TYPE(const OSSL_PARAM *p, TYPE *val);
        int OSSL_PARAM_set_TYPE(OSSL_PARAM *p, TYPE val);

        int OSSL_PARAM_get_BN(const OSSL_PARAM *p, BIGNUM **val);
        int OSSL_PARAM_set_BN(OSSL_PARAM *p, const BIGNUM *val);

        int OSSL_PARAM_get_utf8_string(const OSSL_PARAM *p, char **val,
                                       size_t max_len);
        int OSSL_PARAM_set_utf8_string(OSSL_PARAM *p, const char *val);

        int OSSL_PARAM_get_octet_string(const OSSL_PARAM *p, void **val,
                                        size_t max_len, size_t *used_len);
        int OSSL_PARAM_set_octet_string(OSSL_PARAM *p, const void *val, size_t len);

        int OSSL_PARAM_get_utf8_ptr(const OSSL_PARAM *p, const char **val);
        int OSSL_PARAM_set_utf8_ptr(OSSL_PARAM *p, const char *val);

        int OSSL_PARAM_get_octet_ptr(const OSSL_PARAM *p, const void **val,
                                     size_t *used_len);
        int OSSL_PARAM_set_octet_ptr(OSSL_PARAM *p, const void *val,
                                     size_t used_len);

        int OSSL_PARAM_get_utf8_string_ptr(const OSSL_PARAM *p, const char **val);
        int OSSL_PARAM_get_octet_string_ptr(const OSSL_PARAM *p, const void **val,
                                            size_t *used_len);

        int OSSL_PARAM_modified(const OSSL_PARAM *param);
        void OSSL_PARAM_set_all_unmodified(OSSL_PARAM *params);

DESCRIPTION
       A collection of utility functions that simplify and add type safety to
       the OSSL_PARAM(3) arrays.  The following TTYYPPEE names are supported:

       ⊕
        double

       ⊕
        int

       ⊕
        int32 (int32_t)

       ⊕
        int64 (int64_t)

       ⊕
        long int (long)

       ⊕
        time_t

       ⊕
        size_t

       ⊕
        uint32 (uint32_t)

       ⊕
        uint64 (uint64_t)

       ⊕
        unsigned int (uint)

       ⊕
        unsigned long int (ulong)

       OSSL_PARAM_TYPE() are a series of macros designed to assist
       initialising an array of OSSL_PARAM(3) structures.  Each of these
       macros defines a parameter of the specified TTYYPPEE with the provided key
       and parameter variable address.

       OSSL_PARAM_utf8_string(), OSSL_PARAM_octet_string(),
       OSSL_PARAM_utf8_ptr(), OSSL_PARAM_octet_ptr(), OSSL_PARAM_BN() are
       macros that provide support for defining UTF8 strings, OCTET strings
       and big numbers.  A parameter with name key is defined.  The storage
       for this parameter is at address and is of size bytes.

       OSSL_PARAM_END provides an end of parameter list marker.  This should
       terminate all OSSL_PARAM(3) arrays.

       The OSSL_PARAM_DEFN() macro provides the ability to construct a single
       OSSL_PARAM(3) (typically used in the construction of OSSL_PARAM
       arrays). The key, type, addr and sz arguments correspond to the key,
       data_type, data and data_size fields of the OSSL_PARAM(3) structure as
       described on the OSSL_PARAM(3) page.

       OSSL_PARAM_construct_TYPE() are a series of functions that create
       OSSL_PARAM(3) records dynamically.  A parameter with name key is
       created.  The parameter will use storage pointed to by buf and return
       size of ret.

       OSSL_PARAM_construct_BN() is a function that constructs a large integer
       OSSL_PARAM(3) structure.  A parameter with name key, storage buf, size
       bsize and return size rsize is created.

       OSSL_PARAM_construct_utf8_string() is a function that constructs a UTF8
       string OSSL_PARAM(3) structure.  A parameter with name key, storage buf
       and size bsize is created.  If bsize is zero, the string length is
       determined using strlen(3).  Generally pass zero for bsize instead of
       calling strlen(3) yourself.

       OSSL_PARAM_construct_octet_string() is a function that constructs an
       OCTET string OSSL_PARAM(3) structure.  A parameter with name key,
       storage buf and size bsize is created.

       OSSL_PARAM_construct_utf8_ptr() is a function that constructs a UTF8
       string pointer OSSL_PARAM(3) structure.  A parameter with name key,
       storage pointer *buf and size bsize is created.

       OSSL_PARAM_construct_octet_ptr() is a function that constructs an OCTET
       string pointer OSSL_PARAM(3) structure.  A parameter with name key,
       storage pointer *buf and size bsize is created.

       OSSL_PARAM_construct_end() is a function that constructs the
       terminating OSSL_PARAM(3) structure.

       OSSL_PARAM_locate() is a function that searches an array of parameters
       for the one matching the key name.

       OSSL_PARAM_locate_const() behaves exactly like OSSL_PARAM_locate()
       except for the presence of const for the array argument and its return
       value.

       OSSL_PARAM_get_TYPE() retrieves a value of type TTYYPPEE from the parameter
       p.  The value is copied to the address val.  Type coercion takes place
       as discussed in the NOTES section.

       OSSL_PARAM_set_TYPE() stores a value val of type TTYYPPEE into the
       parameter p.  If the parameter's data field is NULL, then only its
       return_size field will be assigned the size the parameter's data buffer
       should have.  Type coercion takes place as discussed in the NOTES
       section.

       OSSL_PARAM_get_BN() retrieves a BIGNUM from the parameter pointed to by
       p.  The BIGNUM referenced by val is updated and is allocated if *val is
       NULL.

       OSSL_PARAM_set_BN() stores the BIGNUM val into the parameter p.  If the
       parameter's data field is NULL, then only its return_size field will be
       assigned the size the parameter's data buffer should have.

       OSSL_PARAM_get_utf8_string() retrieves a UTF8 string from the parameter
       pointed to by p.  The string is stored into *val with a size limit of
       max_len, which must be large enough to accommodate a terminating NUL
       byte, otherwise this function will fail.  If *val is NULL, memory is
       allocated for the string (including the terminating  NUL byte) and
       max_len is ignored.  If memory is allocated by this function, it must
       be freed by the caller.

       OSSL_PARAM_set_utf8_string() sets a UTF8 string from the parameter
       pointed to by p to the value referenced by val.  If the parameter's
       data field isn't NULL, its data_size must indicate that the buffer is
       large enough to accommodate the string that val points at, not
       including the terminating NUL byte, or this function will fail.  A
       terminating NUL byte is added only if the parameter's data_size
       indicates the buffer is longer than the string length, otherwise the
       string will not be NUL terminated.  If the parameter's data field is
       NULL, then only its return_size field will be assigned the minimum size
       the parameter's data buffer should have to accommodate the string, not
       including a terminating NUL byte.

       OSSL_PARAM_get_octet_string() retrieves an OCTET string from the
       parameter pointed to by p.  The OCTETs are either stored into *val with
       a length limit of max_len or, in the case when *val is NULL, memory is
       allocated and max_len is ignored. *used_len is populated with the
       number of OCTETs stored. If val is NULL then the OCTETS are not stored,
       but *used_len is still populated.  If memory is allocated by this
       function, it must be freed by the caller.

       OSSL_PARAM_set_octet_string() sets an OCTET string from the parameter
       pointed to by p to the value referenced by val.  If the parameter's
       data field is NULL, then only its return_size field will be assigned
       the size the parameter's data buffer should have.

       OSSL_PARAM_get_utf8_ptr() retrieves the UTF8 string pointer from the
       parameter referenced by p and stores it in *val.

       OSSL_PARAM_set_utf8_ptr() sets the UTF8 string pointer in the parameter
       referenced by p to the values val.

       OSSL_PARAM_get_octet_ptr() retrieves the OCTET string pointer from the
       parameter referenced by p and stores it in *val.  The length of the
       OCTET string is stored in *used_len.

       OSSL_PARAM_set_octet_ptr() sets the OCTET string pointer in the
       parameter referenced by p to the values val.  The length of the OCTET
       string is provided by used_len.

       OSSL_PARAM_get_utf8_string_ptr() retrieves the pointer to a UTF8 string
       from the parameter pointed to by p, and stores that pointer in *val.
       This is different from OSSL_PARAM_get_utf8_string(), which copies the
       string.

       OSSL_PARAM_get_octet_string_ptr() retrieves the pointer to a octet
       string from the parameter pointed to by p, and stores that pointer in
       *val, along with the string's length in *used_len.  This is different
       from OSSL_PARAM_get_octet_string(), which copies the string.

       The OSSL_PARAM_UNMODIFIED macro is used to detect if a parameter was
       set.  On creation, via either the macros or construct calls, the
       return_size field is set to this.  If the parameter is set using the
       calls defined herein, the return_size field is changed.

       OSSL_PARAM_modified() queries if the parameter param has been set or
       not using the calls defined herein.

       OSSL_PARAM_set_all_unmodified() resets the unused indicator for all
       parameters in the array params.

RETURN VALUES
       OSSL_PARAM_construct_TYPE(), OSSL_PARAM_construct_BN(),
       OSSL_PARAM_construct_utf8_string(),
       OSSL_PARAM_construct_octet_string(), OSSL_PARAM_construct_utf8_ptr()
       and OSSL_PARAM_construct_octet_ptr() return a populated OSSL_PARAM(3)
       structure.

       OSSL_PARAM_locate() and OSSL_PARAM_locate_const() return a pointer to
       the matching OSSL_PARAM(3) object.  They return NULL on error or when
       no object matching key exists in the array.

       OSSL_PARAM_modified() returns 1 if the parameter was set and 0
       otherwise.

       All other functions return 1 on success and 0 on failure.

NOTES
       Native types will be converted as required only if the value is exactly
       representable by the target type or parameter.  Apart from that, the
       functions must be used appropriately for the expected type of the
       parameter.

       OSSL_PARAM_get_BN() and OSSL_PARAM_set_BN() currently only support
       nonnegative BIGNUMs, and by consequence, only
       OSSL_PARAM_UNSIGNED_INTEGER.  OSSL_PARAM_construct_BN() currently
       constructs an OSSL_PARAM(3) structure with the data type
       OSSL_PARAM_UNSIGNED_INTEGER.

       For OSSL_PARAM_construct_utf8_ptr() and
       OSSL_PARAM_consstruct_octet_ptr(), bsize is not relevant if the purpose
       is to send the OSSL_PARAM(3) array to a responder, i.e. to get
       parameter data back.  In that case, bsize can safely be given zero.
       See "DESCRIPTION" in OSSL_PARAM(3) for further information on the
       possible purposes.

EXAMPLES
       Reusing the examples from OSSL_PARAM(3) to just show how OSSL_PARAM(3)
       arrays can be handled using the macros and functions defined herein.

   Example 1
       This example is for setting parameters on some object:

           #include <openssl/core.h>

           const char *foo = "some string";
           size_t foo_l = strlen(foo);
           const char bar[] = "some other string";
           const OSSL_PARAM set[] = {
               OSSL_PARAM_utf8_ptr("foo", &foo, foo_l),
               OSSL_PARAM_utf8_string("bar", bar, sizeof(bar) - 1),
               OSSL_PARAM_END
           };

   Example 2
       This example is for requesting parameters on some object, and also
       demonstrates that the requester isn't obligated to request all
       available parameters:

           const char *foo = NULL;
           char bar[1024];
           OSSL_PARAM request[] = {
               OSSL_PARAM_utf8_ptr("foo", &foo, 0),
               OSSL_PARAM_utf8_string("bar", bar, sizeof(bar)),
               OSSL_PARAM_END
           };

       A responder that receives this array (as "params" in this example)
       could fill in the parameters like this:

           /* OSSL_PARAM *params */

           OSSL_PARAM *p;

           if ((p = OSSL_PARAM_locate(params, "foo")) != NULL)
               OSSL_PARAM_set_utf8_ptr(p, "foo value");
           if ((p = OSSL_PARAM_locate(params, "bar")) != NULL)
               OSSL_PARAM_set_utf8_string(p, "bar value");
           if ((p = OSSL_PARAM_locate(params, "cookie")) != NULL)
               OSSL_PARAM_set_utf8_ptr(p, "cookie value");

SEE ALSO
       openssl-core.h(7), OSSL_PARAM(3)

HISTORY
       These APIs were introduced in OpenSSL 3.0.

COPYRIGHT
       Copyright 2019-2023 The OpenSSL Project Authors. All Rights Reserved.

       Licensed under the Apache License 2.0 (the "License").  You may not use
       this file except in compliance with the License.  You can obtain a copy
       in the file LICENSE in the source distribution or at
       <https://www.openssl.org/source/license.html>.



3.0.12                            2023-10-25                 OSSL_PARAM_int(3)