.Dd $Mdocdate: November 3 2016 $ .Dt EVP_PKEY_ENCRYPT 3 .Os .Sh NAME .Nm EVP_PKEY_encrypt_init , .Nm EVP_PKEY_encrypt .Nd encrypt using a public key algorithm .Sh SYNOPSIS .In openssl/evp.h .Ft int .Fo EVP_PKEY_encrypt_init .Fa "EVP_PKEY_CTX *ctx" .Fc .Ft int .Fo EVP_PKEY_encrypt .Fa "EVP_PKEY_CTX *ctx" .Fa "unsigned char *out" .Fa "size_t *outlen" .Fa "const unsigned char *in" .Fa "size_t inlen" .Fc .Sh DESCRIPTION The .Fn EVP_PKEY_encrypt_init function initializes a public key algorithm context using key .Fa ctx->pkey for an encryption operation. .Pp The .Fn EVP_PKEY_encrypt function performs a public key encryption operation using .Fa ctx . The data to be encrypted is specified using the .Fa in and .Fa inlen parameters. If .Fa out is .Dv NULL , then the maximum size of the output buffer is written to the .Fa outlen parameter. If .Fa out is not .Dv NULL , then before the call the .Fa outlen parameter should contain the length of the .Fa out buffer, if the call is successful the encrypted data is written to .Fa out and the amount of data written to .Fa outlen . .Pp After the call to .Fn EVP_PKEY_encrypt_init , algorithm specific control operations can be performed to set any appropriate parameters for the operation. .Pp The function .Fn EVP_PKEY_encrypt can be called more than once on the same context if several operations are performed using the same parameters. .Sh RETURN VALUES .Fn EVP_PKEY_encrypt_init and .Fn 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. .Sh EXAMPLES Encrypt data using OAEP (for RSA keys): .Bd -literal #include #include EVP_PKEY_CTX *ctx; unsigned char *out, *in; size_t outlen, inlen; EVP_PKEY *key; /* NB: assumes key in, inlen are already set up * and that key is an RSA public key */ ctx = EVP_PKEY_CTX_new(key); if (!ctx) /* Error occurred */ if (EVP_PKEY_encrypt_init(ctx) <= 0) /* Error */ if (EVP_PKEY_CTX_set_rsa_padding(ctx, RSA_PKCS1_OAEP_PADDING) <= 0) /* Error */ /* Determine buffer length */ if (EVP_PKEY_encrypt(ctx, NULL, &outlen, in, inlen) <= 0) /* Error */ out = 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 */ .Ed .Sh SEE ALSO .Xr EVP_PKEY_CTX_new 3 , .Xr EVP_PKEY_decrypt 3 , .Xr EVP_PKEY_derive 3 , .Xr EVP_PKEY_sign 3 , .Xr EVP_PKEY_verify 3 , .Xr EVP_PKEY_verify_recover 3 .Sh HISTORY These functions were first added to OpenSSL 1.0.0.