OpenSSL 1.1+ ChaCha20-Poly1305 API test (RFC 7539 2.8.2)

gistfile1.txt

#include <string.h>
#include <stdint.h>
#include <openssl/evp.h>

uint8_t data[] = {
	0x4c, 0x61, 0x64, 0x69, 0x65, 0x73, 0x20, 0x61, 0x6e, 0x64, 0x20, 0x47, 0x65, 0x6e, 0x74, 0x6c,
	0x65, 0x6d, 0x65, 0x6e, 0x20, 0x6f, 0x66, 0x20, 0x74, 0x68, 0x65, 0x20, 0x63, 0x6c, 0x61, 0x73,
	0x73, 0x20, 0x6f, 0x66, 0x20, 0x27, 0x39, 0x39, 0x3a, 0x20, 0x49, 0x66, 0x20, 0x49, 0x20, 0x63,
	0x6f, 0x75, 0x6c, 0x64, 0x20, 0x6f, 0x66, 0x66, 0x65, 0x72, 0x20, 0x79, 0x6f, 0x75, 0x20, 0x6f,
	0x6e, 0x6c, 0x79, 0x20, 0x6f, 0x6e, 0x65, 0x20, 0x74, 0x69, 0x70, 0x20, 0x66, 0x6f, 0x72, 0x20,
	0x74, 0x68, 0x65, 0x20, 0x66, 0x75, 0x74, 0x75, 0x72, 0x65, 0x2c, 0x20, 0x73, 0x75, 0x6e, 0x73,
	0x63, 0x72, 0x65, 0x65, 0x6e, 0x20, 0x77, 0x6f, 0x75, 0x6c, 0x64, 0x20, 0x62, 0x65, 0x20, 0x69,
	0x74, 0x2e
};

uint8_t aad[] = {
	0x50, 0x51, 0x52, 0x53, 0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7
};

uint8_t key[] = {
	0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f,
	0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f
};

uint8_t nonce[] = {
	0x07, 0x00, 0x00, 0x00,
	0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47
};

uint8_t tag[] = {
	0x1a, 0xe1, 0x0b, 0x59, 0x4f, 0x09, 0xe2, 0x6a, 0x7e, 0x90, 0x2e, 0xcb, 0xd0, 0x60, 0x06, 0x91
};

int main() {
	EVP_CIPHER_CTX *ctx = EVP_CIPHER_CTX_new();
	int outlen;

	uint8_t out[4096];
	uint8_t tagout[12];

	EVP_EncryptInit_ex(ctx, EVP_chacha20_poly1305(), 0, 0, 0);
	EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_SET_IVLEN, 12, 0);
	EVP_EncryptInit_ex(ctx, NULL, NULL, key, nonce);
	EVP_EncryptUpdate(ctx, NULL, &outlen, aad, sizeof(aad));
	EVP_EncryptUpdate(ctx, out, &outlen, data, sizeof(data));
	EVP_EncryptFinal_ex(ctx, out, &outlen);
	EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_GET_TAG, 12, tagout);

	return memcmp(tag, tagout, 12);
}