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/*
* Copyright 2023 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the Apache License 2.0 (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*/
/*
* NB: Changes to this file should also be reflected in
* doc/man7/ossl-guide-quic-multi-stream.pod
*/
#include <string.h>
/* Include the appropriate header file for SOCK_DGRAM */
#ifdef _WIN32 /* Windows */
# include <winsock2.h>
#else /* Linux/Unix */
# include <sys/socket.h>
#endif
#include <openssl/bio.h>
#include <openssl/ssl.h>
#include <openssl/err.h>
/* Helper function to create a BIO connected to the server */
static BIO *create_socket_bio(const char *hostname, const char *port,
BIO_ADDR **peer_addr)
{
int sock = -1;
BIO_ADDRINFO *res;
const BIO_ADDRINFO *ai = NULL;
BIO *bio;
/*
* Lookup IP address info for the server.
*/
if (!BIO_lookup_ex(hostname, port, BIO_LOOKUP_CLIENT, 0, SOCK_DGRAM, 0,
&res))
return NULL;
/*
* Loop through all the possible addresses for the server and find one
* we can connect to.
*/
for (ai = res; ai != NULL; ai = BIO_ADDRINFO_next(ai)) {
/*
* Create a TCP socket. We could equally use non-OpenSSL calls such
* as "socket" here for this and the subsequent connect and close
* functions. But for portability reasons and also so that we get
* errors on the OpenSSL stack in the event of a failure we use
* OpenSSL's versions of these functions.
*/
sock = BIO_socket(BIO_ADDRINFO_family(ai), SOCK_DGRAM, 0, 0);
if (sock == -1)
continue;
/* Connect the socket to the server's address */
if (!BIO_connect(sock, BIO_ADDRINFO_address(ai), 0)) {
BIO_closesocket(sock);
sock = -1;
continue;
}
/* Set to nonblocking mode */
if (!BIO_socket_nbio(sock, 1)) {
BIO_closesocket(sock);
sock = -1;
continue;
}
break;
}
if (sock != -1) {
*peer_addr = BIO_ADDR_dup(BIO_ADDRINFO_address(ai));
if (*peer_addr == NULL) {
BIO_closesocket(sock);
return NULL;
}
}
/* Free the address information resources we allocated earlier */
BIO_ADDRINFO_free(res);
/* If sock is -1 then we've been unable to connect to the server */
if (sock == -1)
return NULL;
/* Create a BIO to wrap the socket */
bio = BIO_new(BIO_s_datagram());
if (bio == NULL) {
BIO_closesocket(sock);
return NULL;
}
/*
* Associate the newly created BIO with the underlying socket. By
* passing BIO_CLOSE here the socket will be automatically closed when
* the BIO is freed. Alternatively you can use BIO_NOCLOSE, in which
* case you must close the socket explicitly when it is no longer
* needed.
*/
BIO_set_fd(bio, sock, BIO_CLOSE);
return bio;
}
/* Server hostname and port details. Must be in quotes */
#ifndef HOSTNAME
# define HOSTNAME "www.example.com"
#endif
#ifndef PORT
# define PORT "443"
#endif
/*
* Simple application to send basic HTTP/1.0 requests to a server and print the
* response on the screen. Note that HTTP/1.0 over QUIC is not a real protocol
* and will not be supported by real world servers. This is for demonstration
* purposes only.
*/
int main(void)
{
SSL_CTX *ctx = NULL;
SSL *ssl = NULL;
SSL *stream1 = NULL, *stream2 = NULL, *stream3 = NULL;
BIO *bio = NULL;
int res = EXIT_FAILURE;
int ret;
unsigned char alpn[] = { 8, 'h', 't', 't', 'p', '/', '1', '.', '0' };
const char *request1 =
"GET /request1.html HTTP/1.0\r\nConnection: close\r\nHost: "HOSTNAME"\r\n\r\n";
const char *request2 =
"GET /request2.html HTTP/1.0\r\nConnection: close\r\nHost: "HOSTNAME"\r\n\r\n";
size_t written, readbytes;
char buf[160];
BIO_ADDR *peer_addr = NULL;
/*
* Create an SSL_CTX which we can use to create SSL objects from. We
* want an SSL_CTX for creating clients so we use
* OSSL_QUIC_client_method() here.
*/
ctx = SSL_CTX_new(OSSL_QUIC_client_method());
if (ctx == NULL) {
printf("Failed to create the SSL_CTX\n");
goto end;
}
/*
* Configure the client to abort the handshake if certificate
* verification fails. Virtually all clients should do this unless you
* really know what you are doing.
*/
SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER, NULL);
/* Use the default trusted certificate store */
if (!SSL_CTX_set_default_verify_paths(ctx)) {
printf("Failed to set the default trusted certificate store\n");
goto end;
}
/* Create an SSL object to represent the TLS connection */
ssl = SSL_new(ctx);
if (ssl == NULL) {
printf("Failed to create the SSL object\n");
goto end;
}
/*
* We will use multiple streams so we will disable the default stream mode.
* This is not a requirement for using multiple streams but is recommended.
*/
if (!SSL_set_default_stream_mode(ssl, SSL_DEFAULT_STREAM_MODE_NONE)) {
printf("Failed to disable the default stream mode\n");
goto end;
}
/*
* Create the underlying transport socket/BIO and associate it with the
* connection.
*/
bio = create_socket_bio(HOSTNAME, PORT, &peer_addr);
if (bio == NULL) {
printf("Failed to crete the BIO\n");
goto end;
}
SSL_set_bio(ssl, bio, bio);
/*
* Tell the server during the handshake which hostname we are attempting
* to connect to in case the server supports multiple hosts.
*/
if (!SSL_set_tlsext_host_name(ssl, HOSTNAME)) {
printf("Failed to set the SNI hostname\n");
goto end;
}
/*
* Ensure we check during certificate verification that the server has
* supplied a certificate for the hostname that we were expecting.
* Virtually all clients should do this unless you really know what you
* are doing.
*/
if (!SSL_set1_host(ssl, HOSTNAME)) {
printf("Failed to set the certificate verification hostname");
goto end;
}
/* SSL_set_alpn_protos returns 0 for success! */
if (SSL_set_alpn_protos(ssl, alpn, sizeof(alpn)) != 0) {
printf("Failed to set the ALPN for the connection\n");
goto end;
}
/* Set the IP address of the remote peer */
if (!SSL_set1_initial_peer_addr(ssl, peer_addr)) {
printf("Failed to set the initial peer address\n");
goto end;
}
/* Connect to the server and perform the TLS handshake */
if ((ret = SSL_connect(ssl)) < 1) {
/*
* If the failure is due to a verification error we can get more
* information about it from SSL_get_verify_result().
*/
if (SSL_get_verify_result(ssl) != X509_V_OK)
printf("Verify error: %s\n",
X509_verify_cert_error_string(SSL_get_verify_result(ssl)));
goto end;
}
/*
* We create two new client initiated streams. The first will be
* bi-directional, and the second will be uni-directional.
*/
stream1 = SSL_new_stream(ssl, 0);
stream2 = SSL_new_stream(ssl, SSL_STREAM_FLAG_UNI);
if (stream1 == NULL || stream2 == NULL) {
printf("Failed to create streams\n");
goto end;
}
/* Write an HTTP GET request on each of our streams to the peer */
if (!SSL_write_ex(stream1, request1, strlen(request1), &written)) {
printf("Failed to write HTTP request on stream 1\n");
goto end;
}
if (!SSL_write_ex(stream2, request2, strlen(request2), &written)) {
printf("Failed to write HTTP request on stream 2\n");
goto end;
}
/*
* In this demo we read all the data from one stream before reading all the
* data from the next stream for simplicity. In practice there is no need to
* do this. We can interleave IO on the different streams if we wish, or
* manage the streams entirely separately on different threads.
*/
printf("Stream 1 data:\n");
/*
* Get up to sizeof(buf) bytes of the response from stream 1 (which is a
* bidirectional stream). We keep reading until the server closes the
* connection.
*/
while (SSL_read_ex(stream1, buf, sizeof(buf), &readbytes)) {
/*
* OpenSSL does not guarantee that the returned data is a string or
* that it is NUL terminated so we use fwrite() to write the exact
* number of bytes that we read. The data could be non-printable or
* have NUL characters in the middle of it. For this simple example
* we're going to print it to stdout anyway.
*/
fwrite(buf, 1, readbytes, stdout);
}
/* In case the response didn't finish with a newline we add one now */
printf("\n");
/*
* Check whether we finished the while loop above normally or as the
* result of an error. The 0 argument to SSL_get_error() is the return
* code we received from the SSL_read_ex() call. It must be 0 in order
* to get here. Normal completion is indicated by SSL_ERROR_ZERO_RETURN. In
* QUIC terms this means that the peer has sent FIN on the stream to
* indicate that no further data will be sent.
*/
switch (SSL_get_error(stream1, 0)) {
case SSL_ERROR_ZERO_RETURN:
/* Normal completion of the stream */
break;
case SSL_ERROR_SSL:
/*
* Some stream fatal error occurred. This could be because of a stream
* reset - or some failure occurred on the underlying connection.
*/
switch (SSL_get_stream_read_state(stream1)) {
case SSL_STREAM_STATE_RESET_REMOTE:
printf("Stream reset occurred\n");
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