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-rw-r--r--examples/client.c699
1 files changed, 699 insertions, 0 deletions
diff --git a/examples/client.c b/examples/client.c
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+++ b/examples/client.c
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+/*
+ * nghttp2 - HTTP/2 C Library
+ *
+ * Copyright (c) 2013 Tatsuhiro Tsujikawa
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+/*
+ * This program is written to show how to use nghttp2 API in C and
+ * intentionally made simple.
+ */
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif /* HAVE_CONFIG_H */
+
+#include <inttypes.h>
+#include <stdlib.h>
+#ifdef HAVE_UNISTD_H
+# include <unistd.h>
+#endif /* HAVE_UNISTD_H */
+#ifdef HAVE_FCNTL_H
+# include <fcntl.h>
+#endif /* HAVE_FCNTL_H */
+#include <sys/types.h>
+#ifdef HAVE_SYS_SOCKET_H
+# include <sys/socket.h>
+#endif /* HAVE_SYS_SOCKET_H */
+#ifdef HAVE_NETDB_H
+# include <netdb.h>
+#endif /* HAVE_NETDB_H */
+#ifdef HAVE_NETINET_IN_H
+# include <netinet/in.h>
+#endif /* HAVE_NETINET_IN_H */
+#include <netinet/tcp.h>
+#include <poll.h>
+#include <signal.h>
+#include <stdio.h>
+#include <assert.h>
+#include <string.h>
+#include <errno.h>
+
+#include <nghttp2/nghttp2.h>
+
+#include <openssl/ssl.h>
+#include <openssl/err.h>
+#include <openssl/conf.h>
+
+enum { IO_NONE, WANT_READ, WANT_WRITE };
+
+#define MAKE_NV(NAME, VALUE) \
+ { \
+ (uint8_t *)NAME, (uint8_t *)VALUE, sizeof(NAME) - 1, sizeof(VALUE) - 1, \
+ NGHTTP2_NV_FLAG_NONE \
+ }
+
+#define MAKE_NV_CS(NAME, VALUE) \
+ { \
+ (uint8_t *)NAME, (uint8_t *)VALUE, sizeof(NAME) - 1, strlen(VALUE), \
+ NGHTTP2_NV_FLAG_NONE \
+ }
+
+struct Connection {
+ SSL *ssl;
+ nghttp2_session *session;
+ /* WANT_READ if SSL/TLS connection needs more input; or WANT_WRITE
+ if it needs more output; or IO_NONE. This is necessary because
+ SSL/TLS re-negotiation is possible at any time. nghttp2 API
+ offers similar functions like nghttp2_session_want_read() and
+ nghttp2_session_want_write() but they do not take into account
+ SSL/TSL connection. */
+ int want_io;
+};
+
+struct Request {
+ char *host;
+ /* In this program, path contains query component as well. */
+ char *path;
+ /* This is the concatenation of host and port with ":" in
+ between. */
+ char *hostport;
+ /* Stream ID for this request. */
+ int32_t stream_id;
+ uint16_t port;
+};
+
+struct URI {
+ const char *host;
+ /* In this program, path contains query component as well. */
+ const char *path;
+ size_t pathlen;
+ const char *hostport;
+ size_t hostlen;
+ size_t hostportlen;
+ uint16_t port;
+};
+
+/*
+ * Returns copy of string |s| with the length |len|. The returned
+ * string is NULL-terminated.
+ */
+static char *strcopy(const char *s, size_t len) {
+ char *dst;
+ dst = malloc(len + 1);
+ memcpy(dst, s, len);
+ dst[len] = '\0';
+ return dst;
+}
+
+/*
+ * Prints error message |msg| and exit.
+ */
+NGHTTP2_NORETURN
+static void die(const char *msg) {
+ fprintf(stderr, "FATAL: %s\n", msg);
+ exit(EXIT_FAILURE);
+}
+
+/*
+ * Prints error containing the function name |func| and message |msg|
+ * and exit.
+ */
+NGHTTP2_NORETURN
+static void dief(const char *func, const char *msg) {
+ fprintf(stderr, "FATAL: %s: %s\n", func, msg);
+ exit(EXIT_FAILURE);
+}
+
+/*
+ * Prints error containing the function name |func| and error code
+ * |error_code| and exit.
+ */
+NGHTTP2_NORETURN
+static void diec(const char *func, int error_code) {
+ fprintf(stderr, "FATAL: %s: error_code=%d, msg=%s\n", func, error_code,
+ nghttp2_strerror(error_code));
+ exit(EXIT_FAILURE);
+}
+
+/*
+ * The implementation of nghttp2_send_callback type. Here we write
+ * |data| with size |length| to the network and return the number of
+ * bytes actually written. See the documentation of
+ * nghttp2_send_callback for the details.
+ */
+static ssize_t send_callback(nghttp2_session *session, const uint8_t *data,
+ size_t length, int flags, void *user_data) {
+ struct Connection *connection;
+ int rv;
+ (void)session;
+ (void)flags;
+
+ connection = (struct Connection *)user_data;
+ connection->want_io = IO_NONE;
+ ERR_clear_error();
+ rv = SSL_write(connection->ssl, data, (int)length);
+ if (rv <= 0) {
+ int err = SSL_get_error(connection->ssl, rv);
+ if (err == SSL_ERROR_WANT_WRITE || err == SSL_ERROR_WANT_READ) {
+ connection->want_io =
+ (err == SSL_ERROR_WANT_READ ? WANT_READ : WANT_WRITE);
+ rv = NGHTTP2_ERR_WOULDBLOCK;
+ } else {
+ rv = NGHTTP2_ERR_CALLBACK_FAILURE;
+ }
+ }
+ return rv;
+}
+
+/*
+ * The implementation of nghttp2_recv_callback type. Here we read data
+ * from the network and write them in |buf|. The capacity of |buf| is
+ * |length| bytes. Returns the number of bytes stored in |buf|. See
+ * the documentation of nghttp2_recv_callback for the details.
+ */
+static ssize_t recv_callback(nghttp2_session *session, uint8_t *buf,
+ size_t length, int flags, void *user_data) {
+ struct Connection *connection;
+ int rv;
+ (void)session;
+ (void)flags;
+
+ connection = (struct Connection *)user_data;
+ connection->want_io = IO_NONE;
+ ERR_clear_error();
+ rv = SSL_read(connection->ssl, buf, (int)length);
+ if (rv < 0) {
+ int err = SSL_get_error(connection->ssl, rv);
+ if (err == SSL_ERROR_WANT_WRITE || err == SSL_ERROR_WANT_READ) {
+ connection->want_io =
+ (err == SSL_ERROR_WANT_READ ? WANT_READ : WANT_WRITE);
+ rv = NGHTTP2_ERR_WOULDBLOCK;
+ } else {
+ rv = NGHTTP2_ERR_CALLBACK_FAILURE;
+ }
+ } else if (rv == 0) {
+ rv = NGHTTP2_ERR_EOF;
+ }
+ return rv;
+}
+
+static int on_frame_send_callback(nghttp2_session *session,
+ const nghttp2_frame *frame, void *user_data) {
+ size_t i;
+ (void)user_data;
+
+ switch (frame->hd.type) {
+ case NGHTTP2_HEADERS:
+ if (nghttp2_session_get_stream_user_data(session, frame->hd.stream_id)) {
+ const nghttp2_nv *nva = frame->headers.nva;
+ printf("[INFO] C ----------------------------> S (HEADERS)\n");
+ for (i = 0; i < frame->headers.nvlen; ++i) {
+ fwrite(nva[i].name, 1, nva[i].namelen, stdout);
+ printf(": ");
+ fwrite(nva[i].value, 1, nva[i].valuelen, stdout);
+ printf("\n");
+ }
+ }
+ break;
+ case NGHTTP2_RST_STREAM:
+ printf("[INFO] C ----------------------------> S (RST_STREAM)\n");
+ break;
+ case NGHTTP2_GOAWAY:
+ printf("[INFO] C ----------------------------> S (GOAWAY)\n");
+ break;
+ }
+ return 0;
+}
+
+static int on_frame_recv_callback(nghttp2_session *session,
+ const nghttp2_frame *frame, void *user_data) {
+ size_t i;
+ (void)user_data;
+
+ switch (frame->hd.type) {
+ case NGHTTP2_HEADERS:
+ if (frame->headers.cat == NGHTTP2_HCAT_RESPONSE) {
+ const nghttp2_nv *nva = frame->headers.nva;
+ struct Request *req;
+ req = nghttp2_session_get_stream_user_data(session, frame->hd.stream_id);
+ if (req) {
+ printf("[INFO] C <---------------------------- S (HEADERS)\n");
+ for (i = 0; i < frame->headers.nvlen; ++i) {
+ fwrite(nva[i].name, 1, nva[i].namelen, stdout);
+ printf(": ");
+ fwrite(nva[i].value, 1, nva[i].valuelen, stdout);
+ printf("\n");
+ }
+ }
+ }
+ break;
+ case NGHTTP2_RST_STREAM:
+ printf("[INFO] C <---------------------------- S (RST_STREAM)\n");
+ break;
+ case NGHTTP2_GOAWAY:
+ printf("[INFO] C <---------------------------- S (GOAWAY)\n");
+ break;
+ }
+ return 0;
+}
+
+/*
+ * The implementation of nghttp2_on_stream_close_callback type. We use
+ * this function to know the response is fully received. Since we just
+ * fetch 1 resource in this program, after reception of the response,
+ * we submit GOAWAY and close the session.
+ */
+static int on_stream_close_callback(nghttp2_session *session, int32_t stream_id,
+ uint32_t error_code, void *user_data) {
+ struct Request *req;
+ (void)error_code;
+ (void)user_data;
+
+ req = nghttp2_session_get_stream_user_data(session, stream_id);
+ if (req) {
+ int rv;
+ rv = nghttp2_session_terminate_session(session, NGHTTP2_NO_ERROR);
+
+ if (rv != 0) {
+ diec("nghttp2_session_terminate_session", rv);
+ }
+ }
+ return 0;
+}
+
+/*
+ * The implementation of nghttp2_on_data_chunk_recv_callback type. We
+ * use this function to print the received response body.
+ */
+static int on_data_chunk_recv_callback(nghttp2_session *session, uint8_t flags,
+ int32_t stream_id, const uint8_t *data,
+ size_t len, void *user_data) {
+ struct Request *req;
+ (void)flags;
+ (void)user_data;
+
+ req = nghttp2_session_get_stream_user_data(session, stream_id);
+ if (req) {
+ printf("[INFO] C <---------------------------- S (DATA chunk)\n"
+ "%lu bytes\n",
+ (unsigned long int)len);
+ fwrite(data, 1, len, stdout);
+ printf("\n");
+ }
+ return 0;
+}
+
+/*
+ * Setup callback functions. nghttp2 API offers many callback
+ * functions, but most of them are optional. The send_callback is
+ * always required. Since we use nghttp2_session_recv(), the
+ * recv_callback is also required.
+ */
+static void setup_nghttp2_callbacks(nghttp2_session_callbacks *callbacks) {
+ nghttp2_session_callbacks_set_send_callback(callbacks, send_callback);
+
+ nghttp2_session_callbacks_set_recv_callback(callbacks, recv_callback);
+
+ nghttp2_session_callbacks_set_on_frame_send_callback(callbacks,
+ on_frame_send_callback);
+
+ nghttp2_session_callbacks_set_on_frame_recv_callback(callbacks,
+ on_frame_recv_callback);
+
+ nghttp2_session_callbacks_set_on_stream_close_callback(
+ callbacks, on_stream_close_callback);
+
+ nghttp2_session_callbacks_set_on_data_chunk_recv_callback(
+ callbacks, on_data_chunk_recv_callback);
+}
+
+/*
+ * Setup SSL/TLS context.
+ */
+static void init_ssl_ctx(SSL_CTX *ssl_ctx) {
+ /* Disable SSLv2 and enable all workarounds for buggy servers */
+ SSL_CTX_set_options(ssl_ctx, SSL_OP_ALL | SSL_OP_NO_SSLv2);
+ SSL_CTX_set_mode(ssl_ctx, SSL_MODE_AUTO_RETRY);
+ SSL_CTX_set_mode(ssl_ctx, SSL_MODE_RELEASE_BUFFERS);
+
+ SSL_CTX_set_alpn_protos(ssl_ctx, (const unsigned char *)"\x02h2", 3);
+}
+
+static void ssl_handshake(SSL *ssl, int fd) {
+ int rv;
+ if (SSL_set_fd(ssl, fd) == 0) {
+ dief("SSL_set_fd", ERR_error_string(ERR_get_error(), NULL));
+ }
+ ERR_clear_error();
+ rv = SSL_connect(ssl);
+ if (rv <= 0) {
+ dief("SSL_connect", ERR_error_string(ERR_get_error(), NULL));
+ }
+}
+
+/*
+ * Connects to the host |host| and port |port|. This function returns
+ * the file descriptor of the client socket.
+ */
+static int connect_to(const char *host, uint16_t port) {
+ struct addrinfo hints;
+ int fd = -1;
+ int rv;
+ char service[NI_MAXSERV];
+ struct addrinfo *res, *rp;
+ snprintf(service, sizeof(service), "%u", port);
+ memset(&hints, 0, sizeof(struct addrinfo));
+ hints.ai_family = AF_UNSPEC;
+ hints.ai_socktype = SOCK_STREAM;
+ rv = getaddrinfo(host, service, &hints, &res);
+ if (rv != 0) {
+ dief("getaddrinfo", gai_strerror(rv));
+ }
+ for (rp = res; rp; rp = rp->ai_next) {
+ fd = socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol);
+ if (fd == -1) {
+ continue;
+ }
+ while ((rv = connect(fd, rp->ai_addr, rp->ai_addrlen)) == -1 &&
+ errno == EINTR)
+ ;
+ if (rv == 0) {
+ break;
+ }
+ close(fd);
+ fd = -1;
+ }
+ freeaddrinfo(res);
+ return fd;
+}
+
+static void make_non_block(int fd) {
+ int flags, rv;
+ while ((flags = fcntl(fd, F_GETFL, 0)) == -1 && errno == EINTR)
+ ;
+ if (flags == -1) {
+ dief("fcntl", strerror(errno));
+ }
+ while ((rv = fcntl(fd, F_SETFL, flags | O_NONBLOCK)) == -1 && errno == EINTR)
+ ;
+ if (rv == -1) {
+ dief("fcntl", strerror(errno));
+ }
+}
+
+static void set_tcp_nodelay(int fd) {
+ int val = 1;
+ int rv;
+ rv = setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &val, (socklen_t)sizeof(val));
+ if (rv == -1) {
+ dief("setsockopt", strerror(errno));
+ }
+}
+
+/*
+ * Update |pollfd| based on the state of |connection|.
+ */
+static void ctl_poll(struct pollfd *pollfd, struct Connection *connection) {
+ pollfd->events = 0;
+ if (nghttp2_session_want_read(connection->session) ||
+ connection->want_io == WANT_READ) {
+ pollfd->events |= POLLIN;
+ }
+ if (nghttp2_session_want_write(connection->session) ||
+ connection->want_io == WANT_WRITE) {
+ pollfd->events |= POLLOUT;
+ }
+}
+
+/*
+ * Submits the request |req| to the connection |connection|. This
+ * function does not send packets; just append the request to the
+ * internal queue in |connection->session|.
+ */
+static void submit_request(struct Connection *connection, struct Request *req) {
+ int32_t stream_id;
+ /* Make sure that the last item is NULL */
+ const nghttp2_nv nva[] = {MAKE_NV(":method", "GET"),
+ MAKE_NV_CS(":path", req->path),
+ MAKE_NV(":scheme", "https"),
+ MAKE_NV_CS(":authority", req->hostport),
+ MAKE_NV("accept", "*/*"),
+ MAKE_NV("user-agent", "nghttp2/" NGHTTP2_VERSION)};
+
+ stream_id = nghttp2_submit_request(connection->session, NULL, nva,
+ sizeof(nva) / sizeof(nva[0]), NULL, req);
+
+ if (stream_id < 0) {
+ diec("nghttp2_submit_request", stream_id);
+ }
+
+ req->stream_id = stream_id;
+ printf("[INFO] Stream ID = %d\n", stream_id);
+}
+
+/*
+ * Performs the network I/O.
+ */
+static void exec_io(struct Connection *connection) {
+ int rv;
+ rv = nghttp2_session_recv(connection->session);
+ if (rv != 0) {
+ diec("nghttp2_session_recv", rv);
+ }
+ rv = nghttp2_session_send(connection->session);
+ if (rv != 0) {
+ diec("nghttp2_session_send", rv);
+ }
+}
+
+static void request_init(struct Request *req, const struct URI *uri) {
+ req->host = strcopy(uri->host, uri->hostlen);
+ req->port = uri->port;
+ req->path = strcopy(uri->path, uri->pathlen);
+ req->hostport = strcopy(uri->hostport, uri->hostportlen);
+ req->stream_id = -1;
+}
+
+static void request_free(struct Request *req) {
+ free(req->host);
+ free(req->path);
+ free(req->hostport);
+}
+
+/*
+ * Fetches the resource denoted by |uri|.
+ */
+static void fetch_uri(const struct URI *uri) {
+ nghttp2_session_callbacks *callbacks;
+ int fd;
+ SSL_CTX *ssl_ctx;
+ SSL *ssl;
+ struct Request req;
+ struct Connection connection;
+ int rv;
+ nfds_t npollfds = 1;
+ struct pollfd pollfds[1];
+
+ request_init(&req, uri);
+
+ /* Establish connection and setup SSL */
+ fd = connect_to(req.host, req.port);
+ if (fd == -1) {
+ die("Could not open file descriptor");
+ }
+ ssl_ctx = SSL_CTX_new(TLS_client_method());
+ if (ssl_ctx == NULL) {
+ dief("SSL_CTX_new", ERR_error_string(ERR_get_error(), NULL));
+ }
+ init_ssl_ctx(ssl_ctx);
+ ssl = SSL_new(ssl_ctx);
+ if (ssl == NULL) {
+ dief("SSL_new", ERR_error_string(ERR_get_error(), NULL));
+ }
+ /* To simplify the program, we perform SSL/TLS handshake in blocking
+ I/O. */
+ ssl_handshake(ssl, fd);
+
+ connection.ssl = ssl;
+ connection.want_io = IO_NONE;
+
+ /* Here make file descriptor non-block */
+ make_non_block(fd);
+ set_tcp_nodelay(fd);
+
+ printf("[INFO] SSL/TLS handshake completed\n");
+
+ rv = nghttp2_session_callbacks_new(&callbacks);
+
+ if (rv != 0) {
+ diec("nghttp2_session_callbacks_new", rv);
+ }
+
+ setup_nghttp2_callbacks(callbacks);
+
+ rv = nghttp2_session_client_new(&connection.session, callbacks, &connection);
+
+ nghttp2_session_callbacks_del(callbacks);
+
+ if (rv != 0) {
+ diec("nghttp2_session_client_new", rv);
+ }
+
+ rv = nghttp2_submit_settings(connection.session, NGHTTP2_FLAG_NONE, NULL, 0);
+
+ if (rv != 0) {
+ diec("nghttp2_submit_settings", rv);
+ }
+
+ /* Submit the HTTP request to the outbound queue. */
+ submit_request(&connection, &req);
+
+ pollfds[0].fd = fd;
+ ctl_poll(pollfds, &connection);
+
+ /* Event loop */
+ while (nghttp2_session_want_read(connection.session) ||
+ nghttp2_session_want_write(connection.session)) {
+ int nfds = poll(pollfds, npollfds, -1);
+ if (nfds == -1) {
+ dief("poll", strerror(errno));
+ }
+ if (pollfds[0].revents & (POLLIN | POLLOUT)) {
+ exec_io(&connection);
+ }
+ if ((pollfds[0].revents & POLLHUP) || (pollfds[0].revents & POLLERR)) {
+ die("Connection error");
+ }
+ ctl_poll(pollfds, &connection);
+ }
+
+ /* Resource cleanup */
+ nghttp2_session_del(connection.session);
+ SSL_shutdown(ssl);
+ SSL_free(ssl);
+ SSL_CTX_free(ssl_ctx);
+ shutdown(fd, SHUT_WR);
+ close(fd);
+ request_free(&req);
+}
+
+static int parse_uri(struct URI *res, const char *uri) {
+ /* We only interested in https */
+ size_t len, i, offset;
+ int ipv6addr = 0;
+ memset(res, 0, sizeof(struct URI));
+ len = strlen(uri);
+ if (len < 9 || memcmp("https://", uri, 8) != 0) {
+ return -1;
+ }
+ offset = 8;
+ res->host = res->hostport = &uri[offset];
+ res->hostlen = 0;
+ if (uri[offset] == '[') {
+ /* IPv6 literal address */
+ ++offset;
+ ++res->host;
+ ipv6addr = 1;
+ for (i = offset; i < len; ++i) {
+ if (uri[i] == ']') {
+ res->hostlen = i - offset;
+ offset = i + 1;
+ break;
+ }
+ }
+ } else {
+ const char delims[] = ":/?#";
+ for (i = offset; i < len; ++i) {
+ if (strchr(delims, uri[i]) != NULL) {
+ break;
+ }
+ }
+ res->hostlen = i - offset;
+ offset = i;
+ }
+ if (res->hostlen == 0) {
+ return -1;
+ }
+ /* Assuming https */
+ res->port = 443;
+ if (offset < len) {
+ if (uri[offset] == ':') {
+ /* port */
+ const char delims[] = "/?#";
+ int port = 0;
+ ++offset;
+ for (i = offset; i < len; ++i) {
+ if (strchr(delims, uri[i]) != NULL) {
+ break;
+ }
+ if ('0' <= uri[i] && uri[i] <= '9') {
+ port *= 10;
+ port += uri[i] - '0';
+ if (port > 65535) {
+ return -1;
+ }
+ } else {
+ return -1;
+ }
+ }
+ if (port == 0) {
+ return -1;
+ }
+ offset = i;
+ res->port = (uint16_t)port;
+ }
+ }
+ res->hostportlen = (size_t)(uri + offset + ipv6addr - res->host);
+ for (i = offset; i < len; ++i) {
+ if (uri[i] == '#') {
+ break;
+ }
+ }
+ if (i - offset == 0) {
+ res->path = "/";
+ res->pathlen = 1;
+ } else {
+ res->path = &uri[offset];
+ res->pathlen = i - offset;
+ }
+ return 0;
+}
+
+int main(int argc, char **argv) {
+ struct URI uri;
+ struct sigaction act;
+ int rv;
+
+ if (argc < 2) {
+ die("Specify a https URI");
+ }
+
+ memset(&act, 0, sizeof(struct sigaction));
+ act.sa_handler = SIG_IGN;
+ sigaction(SIGPIPE, &act, 0);
+
+ rv = parse_uri(&uri, argv[1]);
+ if (rv != 0) {
+ die("parse_uri failed");
+ }
+ fetch_uri(&uri);
+ return EXIT_SUCCESS;
+}