QUIC: Add HTTP/3 demo using nghttp3

Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Tim Hudson <tjh@openssl.org>
(Merged from #22369)

demos/http3/Makefile

@@ -0,0 +1,14 @@
+CFLAGS = -I../../include -g -Wall
+LDFLAGS = -L../..
+LDLIBS = -lcrypto -lssl -lnghttp3
+
+all: ossl-nghttp3-demo
+
+clean:
+	$(RM) -f ossl-nghttp3-demo *.o
+
+ossl-nghttp3-demo: ossl-nghttp3-demo.o ossl-nghttp3.o
+	$(CC) $(CFLAGS) -o "$@" $^ $(LDFLAGS) $(LDLIBS)
+
+%.o: %.c
+	$(CC) $(CFLAGS) -c -o "$@" "$<"

demos/http3/ossl-nghttp3-demo.c

@@ -0,0 +1,142 @@
+#include "ossl-nghttp3.h"
+#include <openssl/err.h>
+
+static int done;
+
+static void make_nv(nghttp3_nv *nv, const char *name, const char *value)
+{
+    nv->name        = (uint8_t *)name;
+    nv->value       = (uint8_t *)value;
+    nv->namelen     = strlen(name);
+    nv->valuelen    = strlen(value);
+    nv->flags       = NGHTTP3_NV_FLAG_NONE;
+}
+
+static int on_recv_header(nghttp3_conn *h3conn, int64_t stream_id,
+                          int32_t token,
+                          nghttp3_rcbuf *name, nghttp3_rcbuf *value,
+                          uint8_t flags,
+                          void *conn_user_data,
+                          void *stream_user_data)
+{
+    nghttp3_vec vname, vvalue;
+
+    /* Received a single HTTP header. */
+    vname   = nghttp3_rcbuf_get_buf(name);
+    vvalue  = nghttp3_rcbuf_get_buf(value);
+
+    fwrite(vname.base, vname.len, 1, stderr);
+    fprintf(stderr, ": ");
+    fwrite(vvalue.base, vvalue.len, 1, stderr);
+    fprintf(stderr, "\n");
+
+    return 0;
+}
+
+static int on_end_headers(nghttp3_conn *h3conn, int64_t stream_id,
+                          int fin,
+                          void *conn_user_data, void *stream_user_data)
+{
+    fprintf(stderr, "\n");
+    return 0;
+}
+
+static int on_recv_data(nghttp3_conn *h3conn, int64_t stream_id,
+                        const uint8_t *data, size_t datalen,
+                        void *conn_user_data, void *stream_user_data)
+{
+    ssize_t wr;
+
+    /* HTTP response body data - write it to stdout. */
+    while (datalen > 0) {
+        wr = fwrite(data, 1, datalen, stdout);
+        if (wr < 0)
+            return 1;
+
+        data    += wr;
+        datalen -= wr;
+    }
+
+    return 0;
+}
+
+static int on_end_stream(nghttp3_conn *h3conn, int64_t stream_id,
+                         void *conn_user_data, void *stream_user_data)
+{
+    /* HTTP transaction is done - set done flag so that we stop looping. */
+    done = 1;
+    return 0;
+}
+
+int main(int argc, char **argv)
+{
+    int ret = 1;
+    SSL_CTX *ctx = NULL;
+    H3_CONN *conn = NULL;
+    nghttp3_nv nva[16];
+    nghttp3_callbacks callbacks = {0};
+    size_t num_nv = 0;
+    const char *addr;
+
+    /* Check arguments. */
+    if (argc < 2) {
+        fprintf(stderr, "usage: %s <host:port>\n", argv[0]);
+        goto err;
+    }
+
+    addr = argv[1];
+
+    /* Setup SSL_CTX. */
+    if ((ctx = SSL_CTX_new(OSSL_QUIC_client_method())) == NULL)
+        goto err;
+
+    SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER, NULL);
+
+    if (SSL_CTX_set_default_verify_paths(ctx) == 0)
+        goto err;
+
+    /* Setup callbacks. */
+    callbacks.recv_header   = on_recv_header;
+    callbacks.end_headers   = on_end_headers;
+    callbacks.recv_data     = on_recv_data;
+    callbacks.end_stream    = on_end_stream;
+
+    /* Create connection. */
+    if ((conn = H3_CONN_new_for_addr(ctx, addr, &callbacks,
+                                     NULL, NULL)) == NULL) {
+        ERR_raise_data(ERR_LIB_USER, ERR_R_OPERATION_FAIL,
+                       "cannot create HTTP/3 connection");
+        goto err;
+    }
+
+    /* Build HTTP headers. */
+    make_nv(&nva[num_nv++], ":method", "GET");
+    make_nv(&nva[num_nv++], ":scheme", "https");
+    make_nv(&nva[num_nv++], ":authority", addr);
+    make_nv(&nva[num_nv++], ":path", "/");
+    make_nv(&nva[num_nv++], "user-agent", "OpenSSL-Demo/nghttp3");
+
+    /* Submit request. */
+    if (!H3_CONN_submit_request(conn, nva, num_nv, NULL, NULL)) {
+        ERR_raise_data(ERR_LIB_USER, ERR_R_OPERATION_FAIL,
+                       "cannot submit HTTP/3 request");
+        goto err;
+    }
+
+    /* Wait for request to complete. */
+    while (!done)
+        if (!H3_CONN_handle_events(conn)) {
+            ERR_raise_data(ERR_LIB_USER, ERR_R_OPERATION_FAIL,
+                           "cannot handle events");
+            goto err;
+        }
+
+    ret = 0;
+err:
+    if (ret != 0)
+        ERR_print_errors_fp(stderr);
+
+    H3_CONN_free(conn);
+    SSL_CTX_free(ctx);
+    return ret;
+}