RSA_PUBLIC_ENCRYPT(3ssl) OpenSSL RSA_PUBLIC_ENCRYPT(3ssl) RSA_public_encrypt, RSA_private_decrypt - RSA #include OpenSSL 3.0 OPENSSL_API_COMPAT openssl_user_macros(7): int RSA_public_encrypt(int flen, const unsigned char *from, unsigned char *to, RSA *rsa, int padding); int RSA_private_decrypt(int flen, const unsigned char *from, unsigned char *to, RSA *rsa, int padding); . EVP_PKEY_encrypt_init_ex(3) EVP_PKEY_encrypt(3) EVP_PKEY_decrypt_init_ex(3) EVP_PKEY_decrypt(3). RSA_public_encrypt() flen from ( ) rsa to. to RSA_size(rsa) . padding : RSA_PKCS1_PADDING PKCS #1 v1.5. . RSA_PKCS1_OAEP_PADDING . . RSA_PKCS1_OAEP_PADDING EME-OAEP PKCS #1 v2.0 SHA-1 MGF1 . . RSA_NO_PADDING RSA . . RSA . flen RSA_size(rsa) - 11 PKCS #1 v1.5 RSA_size(rsa) - 42 RSA_PKCS1_OAEP_PADDING RSA_size(rsa) RSA_NO_PADDING. RSA_NO_PADDING RSA_public_encrypt() . to RSA_size(rsa) . to from. RSA_private_decrypt() flen from rsa to. flen RSA_size(rsa) . RSA_public_encrypt() . to ( RSA_size(rsa) RSA_NO_PADDING RSA_size(rsa) - 11 PKCS #1 v1.5 RSA_size(rsa) - 42 RSA_PKCS1_OAEP_PADDING). padding . to from. RSA_public_encrypt() ( RSA_size(rsa)). RSA_private_decrypt() . 0 . -1 ERR_get_error(3). RSA_PKCS1_PADDING Bleichenbacher. PKCS #1 v1.5. RSA_PKCS1_OAEP_PADDING. OpenSSL 3.2.0 Bleichenbacher. 3.2.0 OpenSSL . . . ERR_set_mark(3) ERR_pop_to_mark(3) ERR_clear_error(3). SSL, PKCS #1 v2.0 ERR_get_error(3), RAND_bytes(3), RSA_size(3), EVP_PKEY_decrypt(3), EVP_PKEY_encrypt(3) OpenSSL 3.0. 2000-2024 OpenSSL. . Apache 2.0 ( ""). . LICENSE . 3 . . : . 3.6.2 7 2026 RSA_PUBLIC_ENCRYPT(3ssl)