Hello,
I can't figure out how OpenSSL connections work.
I would like to use 2 bios (rbio, wbio) which will be shared for all my connections.
The problem is that I really don't understand the error messages.
I never get an SSL_ERROR_WANT_WRITE error code, I only get SSL_ERROR_WANT_READ.
For example, for the handshake, whether I have to send or receive data, I only receive the error SSL_ERROR_WANT_READ.
(calls are blocking for simplicity)
int main()
{
struct addrinfo hints, *result;
memset(&hints, 0, sizeof(struct addrinfo));
hints.ai_family = AF_UNSPEC;
hints.ai_socktype = SOCK_STREAM;
if (getaddrinfo("google.com", "443", &hints, &result) != 0) {
printf("getaddrinfo error");
exit(1);
}
int fd = -1;
for (; result != nullptr; result = result->ai_next) {
fd = socket(result->ai_family, result->ai_socktype, result->ai_protocol);
if (fd < 0)
continue;
int res = connect(fd, result->ai_addr, result->ai_addrlen);
if (res == -1) {
continue;
} break;
}
if (fd < 0) {
printf("Connection error");
exit(1);
}
freeaddrinfo(result);
SSL_library_init();
OpenSSL_add_all_algorithms();
SSL_load_error_strings();
ERR_load_BIO_strings();
ERR_load_crypto_strings();
SSL_CTX *ctx = SSL_CTX_new(SSLv23_method());
BIO *rbio = BIO_new(BIO_s_mem());
BIO *wbio = BIO_new(BIO_s_mem());
SSL *ssl = SSL_new(ctx);
SSL_set_bio(ssl, rbio, wbio);
SSL_set_connect_state(ssl);
int n;
do {
n = SSL_do_handshake(ssl);
n = SSL_get_error(ssl, n);
if (n == SSL_ERROR_WANT_READ) {
char buffer[4096];
int r = BIO_read(wbio, buffer, sizeof(buffer));
int error = SSL_get_error(ssl, r);
if (error == SSL_ERROR_WANT_READ) {
r = read(fd, buffer, sizeof(buffer));
BIO_write(rbio, buffer, r);
} else {
send(fd, buffer, r, 0);
}
}
} while (n != SSL_ERROR_NONE);
printf("Connected");
}
How to manage the connection (with several sockets on the same bios) if I don't know if I have to send data or receive it according to the error message?
Thank you
