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OSSL_ENCODER_TO_BIO(3ossl) OpenSSL OSSL_ENCODER_TO_BIO(3ossl)
NAME
OSSL_ENCODER_to_data, OSSL_ENCODER_to_bio, OSSL_ENCODER_to_fp -
Routines to perform an encoding
SYNOPSIS
#include <openssl/encoder.h>
int OSSL_ENCODER_to_data(OSSL_ENCODER_CTX *ctx, unsigned char **pdata,
size_t *pdata_len);
int OSSL_ENCODER_to_bio(OSSL_ENCODER_CTX *ctx, BIO *out);
int OSSL_ENCODER_to_fp(OSSL_ENCODER_CTX *ctx, FILE *fp);
Feature availability macros:
OSSL_ENCODER_to_fp() is only available when OPENSSL_NO_STDIO is
undefined.
DESCRIPTION
OSSL_ENCODER_to_data() runs the encoding process for the context ctx,
with the output going to the *pdata and *pdata_len. If *pdata is NULL
when OSSL_ENCODER_to_data() is called, a buffer will be allocated using
OPENSSL_zalloc(3), and *pdata will be set to point at the start of that
buffer, and *pdata_len will be assigned its length when
OSSL_ENCODER_to_data() returns. If *pdata is non-NULL when
OSSL_ENCODER_to_data() is called, *pdata_len is assumed to have its
size. In this case, *pdata will be set to point after the encoded
bytes, and *pdata_len will be assigned the number of remaining bytes.
OSSL_ENCODER_to_bio() runs the encoding process for the context ctx,
with the output going to the BIO out.
OSSL_ENCODER_to_fp() does the same thing as OSSL_ENCODER_to_bio(),
except that the output is going to the FILE fp.
For OSSL_ENCODER_to_bio() and OSSL_ENCODER_to_fp(), the application is
required to set up the BIO or FILE properly, for example to have it in
text or binary mode as is appropriate for the encoder output type.
RETURN VALUES
OSSL_ENCODER_to_bio(), OSSL_ENCODER_to_fp() and OSSL_ENCODER_to_data()
return 1 on success, or 0 on failure.
EXAMPLES
To encode a pkey as PKCS#8 with PEM format into a bio:
OSSL_ENCODER_CTX *ectx;
const char *format = "PEM";
const char *structure = "PrivateKeyInfo"; /* PKCS#8 structure */
const unsigned char *pass = "my password";
ectx = OSSL_ENCODER_CTX_new_for_pkey(pkey,
OSSL_KEYMGMT_SELECT_KEYPAIR
| OSSL_KEYMGMT_SELECT_DOMAIN_PARAMETERS,
format, structure,
NULL);
if (ectx == NULL) {
/* encoding failure */
}
OSSL_ENCODER_CTX_free(ectx);
To encode a pkey as PKCS#8 with DER format encrypted with AES-256-CBC
into a buffer:
OSSL_ENCODER_CTX *ectx;
const char *format = "DER";
const char *structure = "PrivateKeyInfo"; /* PKCS#8 structure */
const unsigned char *pass = "my password";
unsigned char *data = NULL;
size_t datalen;
ectx = OSSL_ENCODER_CTX_new_for_pkey(pkey,
OSSL_KEYMGMT_SELECT_KEYPAIR
| OSSL_KEYMGMT_SELECT_DOMAIN_PARAMETERS,
format, structure,
NULL);
if (ectx == NULL) {
/* error: no suitable potential encoders found */
}
if (pass != NULL) {
OSSL_ENCODER_CTX_set_passphrase(ectx, pass, strlen(pass));
OSSL_ENCODER_CTX_set_cipher(ctx, "AES-256-CBC", NULL);
}
if (OSSL_ENCODER_to_data(ectx, &data, &datalen)) {
/*
* pkey was successfully encoded into a newly allocated
* data buffer
*/
} else {
/* encoding failure */
}
OSSL_ENCODER_CTX_free(ectx);
SEE ALSO
provider(7), OSSL_ENCODER_CTX(3)
HISTORY
The functions described here were added in OpenSSL 3.0.
COPYRIGHT
Copyright 2019-2021 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>.
3.0.11 2023-09-19 OSSL_ENCODER_TO_BIO(3ossl)