EVP_PKEY_encrypt_init, EVP_PKEY_encrypt - encrypt using a public key algorithm
#include <openssl/evp.h>
int EVP_PKEY_encrypt_init(EVP_PKEY_CTX *ctx);
int EVP_PKEY_encrypt(EVP_PKEY_CTX *ctx,
unsigned char *out, size_t *outlen,
const unsigned char *in, size_t inlen);
The EVP_PKEY_encrypt_init() function initializes a public key algorithm
context using key pkey for an encryption operation.
The EVP_PKEY_encrypt() function performs a public key encryption operation
using ctx. The data to be encrypted is specified using the in and
inlen parameters. If out is NULL then the maximum size of the output
buffer is written to the outlen parameter. If out is not NULL then
before the call the outlen parameter should contain the length of the
out buffer, if the call is successful the encrypted data is written to
out and the amount of data written to outlen.
After the call to EVP_PKEY_encrypt_init() algorithm specific control
operations can be performed to set any appropriate parameters for the
operation.
The function EVP_PKEY_encrypt() can be called more than once on the same
context if several operations are performed using the same parameters.
EVP_PKEY_encrypt_init() and EVP_PKEY_encrypt() return 1 for success and 0
or a negative value for failure. In particular a return value of -2
indicates the operation is not supported by the public key algorithm.
Encrypt data using OAEP (for RSA keys). See also PEM_read_PUBKEY or d2i_X509 for means to load a public key. You may also simply set 'eng = NULL;' to start with the default OpenSSL RSA implementation:
#include <openssl/evp.h> #include <openssl/rsa.h> #include <openssl/engine.h>
EVP_PKEY_CTX *ctx;
ENGINE *eng;
unsigned char *out, *in;
size_t outlen, inlen;
EVP_PKEY *key;
/* NB: assumes eng, key, in, inlen are already set up,
* and that key is an RSA public key
*/
ctx = EVP_PKEY_CTX_new(key,eng);
if (!ctx)
/* Error occurred */
if (EVP_PKEY_encrypt_init(ctx) <= 0)
/* Error */
if (EVP_PKEY_CTX_set_rsa_padding(ctx, RSA_OAEP_PADDING) <= 0)
/* Error */
/* Determine buffer length */
if (EVP_PKEY_encrypt(ctx, NULL, &outlen, in, inlen) <= 0)
/* Error */
out = OPENSSL_malloc(outlen);
if (!out)
/* malloc failure */
if (EVP_PKEY_encrypt(ctx, out, &outlen, in, inlen) <= 0)
/* Error */
/* Encrypted data is outlen bytes written to buffer out */
d2i_X509, engine, EVP_PKEY_CTX_new, EVP_PKEY_decrypt, EVP_PKEY_sign, EVP_PKEY_verify, EVP_PKEY_verify_recover, EVP_PKEY_derive
These functions were first added to OpenSSL 1.0.0.