1 files changed, 478 insertions, 0 deletions
diff --git a/src/shrpx_api_downstream_connection.cc b/src/shrpx_api_downstream_connection.cc
new file mode 100644
index 0000000..254ab59
--- /dev/null
+++ b/src/shrpx_api_downstream_connection.cc
@@ -0,0 +1,478 @@
+/*
+ * nghttp2 - HTTP/2 C Library
+ *
+ * Copyright (c) 2016 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.
+ */
+#include "shrpx_api_downstream_connection.h"
+
+#include <sys/mman.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <cstdlib>
+
+#include "shrpx_client_handler.h"
+#include "shrpx_upstream.h"
+#include "shrpx_downstream.h"
+#include "shrpx_worker.h"
+#include "shrpx_connection_handler.h"
+#include "shrpx_log.h"
+
+namespace shrpx {
+
+namespace {
+// List of API endpoints
+const std::array<APIEndpoint, 2> &apis() {
+  static const auto apis = new std::array<APIEndpoint, 2>{
+      APIEndpoint{
+          StringRef::from_lit("/api/v1beta1/backendconfig"),
+          true,
+          (1 << API_METHOD_POST) | (1 << API_METHOD_PUT),
+          &APIDownstreamConnection::handle_backendconfig,
+      },
+      APIEndpoint{
+          StringRef::from_lit("/api/v1beta1/configrevision"),
+          true,
+          (1 << API_METHOD_GET),
+          &APIDownstreamConnection::handle_configrevision,
+      },
+  };
+
+  return *apis;
+}
+} // namespace
+
+namespace {
+// The method string.  This must be same order of APIMethod.
+constexpr StringRef API_METHOD_STRING[] = {
+    StringRef::from_lit("GET"),
+    StringRef::from_lit("POST"),
+    StringRef::from_lit("PUT"),
+};
+} // namespace
+
+APIDownstreamConnection::APIDownstreamConnection(Worker *worker)
+    : worker_(worker), api_(nullptr), fd_(-1), shutdown_read_(false) {}
+
+APIDownstreamConnection::~APIDownstreamConnection() {
+  if (fd_ != -1) {
+    close(fd_);
+  }
+}
+
+int APIDownstreamConnection::attach_downstream(Downstream *downstream) {
+  if (LOG_ENABLED(INFO)) {
+    DCLOG(INFO, this) << "Attaching to DOWNSTREAM:" << downstream;
+  }
+
+  downstream_ = downstream;
+
+  return 0;
+}
+
+void APIDownstreamConnection::detach_downstream(Downstream *downstream) {
+  if (LOG_ENABLED(INFO)) {
+    DCLOG(INFO, this) << "Detaching from DOWNSTREAM:" << downstream;
+  }
+  downstream_ = nullptr;
+}
+
+int APIDownstreamConnection::send_reply(unsigned int http_status,
+                                        APIStatusCode api_status,
+                                        const StringRef &data) {
+  shutdown_read_ = true;
+
+  auto upstream = downstream_->get_upstream();
+
+  auto &resp = downstream_->response();
+
+  resp.http_status = http_status;
+
+  auto &balloc = downstream_->get_block_allocator();
+
+  StringRef api_status_str;
+
+  switch (api_status) {
+  case APIStatusCode::SUCCESS:
+    api_status_str = StringRef::from_lit("Success");
+    break;
+  case APIStatusCode::FAILURE:
+    api_status_str = StringRef::from_lit("Failure");
+    break;
+  default:
+    assert(0);
+  }
+
+  constexpr auto M1 = StringRef::from_lit("{\"status\":\"");
+  constexpr auto M2 = StringRef::from_lit("\",\"code\":");
+  constexpr auto M3 = StringRef::from_lit("}");
+
+  // 3 is the number of digits in http_status, assuming it is 3 digits
+  // number.
+  auto buflen = M1.size() + M2.size() + M3.size() + data.size() +
+                api_status_str.size() + 3;
+
+  auto buf = make_byte_ref(balloc, buflen);
+  auto p = buf.base;
+
+  p = std::copy(std::begin(M1), std::end(M1), p);
+  p = std::copy(std::begin(api_status_str), std::end(api_status_str), p);
+  p = std::copy(std::begin(M2), std::end(M2), p);
+  p = util::utos(p, http_status);
+  p = std::copy(std::begin(data), std::end(data), p);
+  p = std::copy(std::begin(M3), std::end(M3), p);
+
+  buf.len = p - buf.base;
+
+  auto content_length = util::make_string_ref_uint(balloc, buf.len);
+
+  resp.fs.add_header_token(StringRef::from_lit("content-length"),
+                           content_length, false, http2::HD_CONTENT_LENGTH);
+
+  switch (http_status) {
+  case 400:
+  case 405:
+  case 413:
+    resp.fs.add_header_token(StringRef::from_lit("connection"),
+                             StringRef::from_lit("close"), false,
+                             http2::HD_CONNECTION);
+    break;
+  }
+
+  if (upstream->send_reply(downstream_, buf.base, buf.len) != 0) {
+    return -1;
+  }
+
+  return 0;
+}
+
+namespace {
+const APIEndpoint *lookup_api(const StringRef &path) {
+  switch (path.size()) {
+  case 26:
+    switch (path[25]) {
+    case 'g':
+      if (util::streq_l("/api/v1beta1/backendconfi", std::begin(path), 25)) {
+        return &apis()[0];
+      }
+      break;
+    }
+    break;
+  case 27:
+    switch (path[26]) {
+    case 'n':
+      if (util::streq_l("/api/v1beta1/configrevisio", std::begin(path), 26)) {
+        return &apis()[1];
+      }
+      break;
+    }
+    break;
+  }
+  return nullptr;
+}
+} // namespace
+
+int APIDownstreamConnection::push_request_headers() {
+  auto &req = downstream_->request();
+
+  auto path =
+      StringRef{std::begin(req.path),
+                std::find(std::begin(req.path), std::end(req.path), '?')};
+
+  api_ = lookup_api(path);
+
+  if (!api_) {
+    send_reply(404, APIStatusCode::FAILURE);
+
+    return 0;
+  }
+
+  switch (req.method) {
+  case HTTP_GET:
+    if (!(api_->allowed_methods & (1 << API_METHOD_GET))) {
+      error_method_not_allowed();
+      return 0;
+    }
+    break;
+  case HTTP_POST:
+    if (!(api_->allowed_methods & (1 << API_METHOD_POST))) {
+      error_method_not_allowed();
+      return 0;
+    }
+    break;
+  case HTTP_PUT:
+    if (!(api_->allowed_methods & (1 << API_METHOD_PUT))) {
+      error_method_not_allowed();
+      return 0;
+    }
+    break;
+  default:
+    error_method_not_allowed();
+    return 0;
+  }
+
+  // This works with req.fs.content_length == -1
+  if (req.fs.content_length >
+      static_cast<int64_t>(get_config()->api.max_request_body)) {
+    send_reply(413, APIStatusCode::FAILURE);
+
+    return 0;
+  }
+
+  switch (req.method) {
+  case HTTP_POST:
+  case HTTP_PUT: {
+    char tempname[] = "/tmp/nghttpx-api.XXXXXX";
+#ifdef HAVE_MKOSTEMP
+    fd_ = mkostemp(tempname, O_CLOEXEC);
+#else  // !HAVE_MKOSTEMP
+    fd_ = mkstemp(tempname);
+#endif // !HAVE_MKOSTEMP
+    if (fd_ == -1) {
+      send_reply(500, APIStatusCode::FAILURE);
+
+      return 0;
+    }
+#ifndef HAVE_MKOSTEMP
+    util::make_socket_closeonexec(fd_);
+#endif // HAVE_MKOSTEMP
+    unlink(tempname);
+    break;
+  }
+  }
+
+  downstream_->set_request_header_sent(true);
+  auto src = downstream_->get_blocked_request_buf();
+  auto dest = downstream_->get_request_buf();
+  src->remove(*dest);
+
+  return 0;
+}
+
+int APIDownstreamConnection::error_method_not_allowed() {
+  auto &resp = downstream_->response();
+
+  size_t len = 0;
+  for (uint8_t i = 0; i < API_METHOD_MAX; ++i) {
+    if (api_->allowed_methods & (1 << i)) {
+      // The length of method + ", "
+      len += API_METHOD_STRING[i].size() + 2;
+    }
+  }
+
+  assert(len > 0);
+
+  auto &balloc = downstream_->get_block_allocator();
+
+  auto iov = make_byte_ref(balloc, len + 1);
+  auto p = iov.base;
+  for (uint8_t i = 0; i < API_METHOD_MAX; ++i) {
+    if (api_->allowed_methods & (1 << i)) {
+      auto &s = API_METHOD_STRING[i];
+      p = std::copy(std::begin(s), std::end(s), p);
+      p = std::copy_n(", ", 2, p);
+    }
+  }
+
+  p -= 2;
+  *p = '\0';
+
+  resp.fs.add_header_token(StringRef::from_lit("allow"), StringRef{iov.base, p},
+                           false, -1);
+  return send_reply(405, APIStatusCode::FAILURE);
+}
+
+int APIDownstreamConnection::push_upload_data_chunk(const uint8_t *data,
+                                                    size_t datalen) {
+  if (shutdown_read_ || !api_->require_body) {
+    return 0;
+  }
+
+  auto &req = downstream_->request();
+  auto &apiconf = get_config()->api;
+
+  if (static_cast<size_t>(req.recv_body_length) > apiconf.max_request_body) {
+    send_reply(413, APIStatusCode::FAILURE);
+
+    return 0;
+  }
+
+  ssize_t nwrite;
+  while ((nwrite = write(fd_, data, datalen)) == -1 && errno == EINTR)
+    ;
+  if (nwrite == -1) {
+    auto error = errno;
+    LOG(ERROR) << "Could not write API request body: errno=" << error;
+    send_reply(500, APIStatusCode::FAILURE);
+
+    return 0;
+  }
+
+  // We don't have to call Upstream::resume_read() here, because
+  // request buffer is effectively unlimited.  Actually, we cannot
+  // call it here since it could recursively call this function again.
+
+  return 0;
+}
+
+int APIDownstreamConnection::end_upload_data() {
+  if (shutdown_read_) {
+    return 0;
+  }
+
+  return api_->handler(*this);
+}
+
+int APIDownstreamConnection::handle_backendconfig() {
+  auto &req = downstream_->request();
+
+  if (req.recv_body_length == 0) {
+    send_reply(200, APIStatusCode::SUCCESS);
+
+    return 0;
+  }
+
+  auto rp = mmap(nullptr, req.recv_body_length, PROT_READ, MAP_SHARED, fd_, 0);
+  if (rp == reinterpret_cast<void *>(-1)) {
+    send_reply(500, APIStatusCode::FAILURE);
+    return 0;
+  }
+
+  auto unmapper = defer(munmap, rp, req.recv_body_length);
+
+  Config new_config{};
+  new_config.conn.downstream = std::make_shared<DownstreamConfig>();
+  const auto &downstreamconf = new_config.conn.downstream;
+
+  auto config = get_config();
+  auto &src = config->conn.downstream;
+
+  downstreamconf->timeout = src->timeout;
+  downstreamconf->connections_per_host = src->connections_per_host;
+  downstreamconf->connections_per_frontend = src->connections_per_frontend;
+  downstreamconf->request_buffer_size = src->request_buffer_size;
+  downstreamconf->response_buffer_size = src->response_buffer_size;
+  downstreamconf->family = src->family;
+
+  std::set<StringRef> include_set;
+  std::map<StringRef, size_t> pattern_addr_indexer;
+
+  for (auto first = reinterpret_cast<const uint8_t *>(rp),
+            last = first + req.recv_body_length;
+       first != last;) {
+    auto eol = std::find(first, last, '\n');
+    if (eol == last) {
+      break;
+    }
+
+    if (first == eol || *first == '#') {
+      first = ++eol;
+      continue;
+    }
+
+    auto eq = std::find(first, eol, '=');
+    if (eq == eol) {
+      send_reply(400, APIStatusCode::FAILURE);
+      return 0;
+    }
+
+    auto opt = StringRef{first, eq};
+    auto optval = StringRef{eq + 1, eol};
+
+    auto optid = option_lookup_token(opt.c_str(), opt.size());
+
+    switch (optid) {
+    case SHRPX_OPTID_BACKEND:
+      break;
+    default:
+      first = ++eol;
+      continue;
+    }
+
+    if (parse_config(&new_config, optid, opt, optval, include_set,
+                     pattern_addr_indexer) != 0) {
+      send_reply(400, APIStatusCode::FAILURE);
+      return 0;
+    }
+
+    first = ++eol;
+  }
+
+  auto &tlsconf = config->tls;
+  if (configure_downstream_group(&new_config, config->http2_proxy, true,
+                                 tlsconf) != 0) {
+    send_reply(400, APIStatusCode::FAILURE);
+    return 0;
+  }
+
+  auto conn_handler = worker_->get_connection_handler();
+
+  conn_handler->send_replace_downstream(downstreamconf);
+
+  send_reply(200, APIStatusCode::SUCCESS);
+
+  return 0;
+}
+
+int APIDownstreamConnection::handle_configrevision() {
+  auto config = get_config();
+  auto &balloc = downstream_->get_block_allocator();
+
+  // Construct the following string:
+  //   ,
+  //   "data":{
+  //     "configRevision": N
+  //   }
+  auto data = concat_string_ref(
+      balloc, StringRef::from_lit(R"(,"data":{"configRevision":)"),
+      util::make_string_ref_uint(balloc, config->config_revision),
+      StringRef::from_lit("}"));
+
+  send_reply(200, APIStatusCode::SUCCESS, data);
+
+  return 0;
+}
+
+void APIDownstreamConnection::pause_read(IOCtrlReason reason) {}
+
+int APIDownstreamConnection::resume_read(IOCtrlReason reason, size_t consumed) {
+  return 0;
+}
+
+void APIDownstreamConnection::force_resume_read() {}
+
+int APIDownstreamConnection::on_read() { return 0; }
+
+int APIDownstreamConnection::on_write() { return 0; }
+
+void APIDownstreamConnection::on_upstream_change(Upstream *upstream) {}
+
+bool APIDownstreamConnection::poolable() const { return false; }
+
+const std::shared_ptr<DownstreamAddrGroup> &
+APIDownstreamConnection::get_downstream_addr_group() const {
+  static std::shared_ptr<DownstreamAddrGroup> s;
+  return s;
+}
+
+DownstreamAddr *APIDownstreamConnection::get_addr() const { return nullptr; }
+
+} // namespace shrpx