Trivial TLS server

Here's a trivial TLS server that can be used to test this.

David
---
/*
 * TLS-over-TCP sink server
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include <unistd.h>
#include <netinet/in.h>
#include <netinet/tcp.h>
#include <linux/tls.h>

#define OSERROR(X, Y) do { if ((long)(X) == -1) { perror(Y); exit(1); } } while(0)

static unsigned char buffer[512 * 1024] __attribute__((aligned(4096)));

static void set_tls(int sock)
{
	struct tls12_crypto_info_aes_gcm_128 crypto_info;

	crypto_info.info.version = TLS_1_2_VERSION;
	crypto_info.info.cipher_type = TLS_CIPHER_AES_GCM_128;
	memset(crypto_info.iv,		0, TLS_CIPHER_AES_GCM_128_IV_SIZE);
	memset(crypto_info.rec_seq,	0, TLS_CIPHER_AES_GCM_128_REC_SEQ_SIZE);
	memset(crypto_info.key,		0, TLS_CIPHER_AES_GCM_128_KEY_SIZE);
	memset(crypto_info.salt,	0, TLS_CIPHER_AES_GCM_128_SALT_SIZE);

	OSERROR(setsockopt(sock, SOL_TCP, TCP_ULP, "tls", sizeof("tls")),
		"TCP_ULP");
	OSERROR(setsockopt(sock, SOL_TLS, TLS_TX, &crypto_info, sizeof(crypto_info)),
		"TLS_TX");
	OSERROR(setsockopt(sock, SOL_TLS, TLS_RX, &crypto_info, sizeof(crypto_info)),
		"TLS_RX");
}

int main(int argc, char *argv[])
{
	struct sockaddr_in sin = { .sin_family = AF_INET, .sin_port = htons(5556) };
	int sfd, afd;

	sfd = socket(AF_INET, SOCK_STREAM, 0);
	OSERROR(sfd, "socket");
	OSERROR(bind(sfd, (struct sockaddr *)&sin, sizeof(sin)), "bind");
	OSERROR(listen(sfd, 1), "listen");

	for (;;) {
		afd = accept(sfd, NULL, NULL);
		if (afd != -1) {
			set_tls(afd);
			while (read(afd, buffer, sizeof(buffer)) > 0) {}
			close(afd);
		}
	}
}