diff --git a/src/Makefile.am b/src/Makefile.am
index 18b3ee85..f1d7ddb0 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -62,7 +62,7 @@ nghttpd_SOURCES = ${HELPER_OBJECTS} ${HELPER_HFILES} nghttpd.cc \
 	HttpServer.cc HttpServer.h
 
 NGHTTPX_SRCS = \
-	util.cc util.h timegm.c timegm.h base64.h \
+	util.cc util.h http2.cc http2.h timegm.c timegm.h base64.h \
 	shrpx_config.cc shrpx_config.h \
 	shrpx_error.h \
 	shrpx_listen_handler.cc shrpx_listen_handler.h \
@@ -95,8 +95,8 @@ if HAVE_CUNIT
 check_PROGRAMS += nghttpx-unittest
 nghttpx_unittest_SOURCES = shrpx-unittest.cc \
 	shrpx_ssl_test.cc shrpx_ssl_test.h \
-	shrpx_http_test.cc shrpx_http_test.h \
 	shrpx_downstream_test.cc shrpx_downstream_test.h \
+	http2_test.cc http2_test.h \
 	util_test.cc util_test.h \
 	${NGHTTPX_SRCS}
 nghttpx_unittest_CPPFLAGS = ${AM_CPPFLAGS}\
diff --git a/src/http2.cc b/src/http2.cc
new file mode 100644
index 00000000..e94cfc31
--- /dev/null
+++ b/src/http2.cc
@@ -0,0 +1,312 @@
+/*
+ * nghttp2 - HTTP/2.0 C Library
+ *
+ * Copyright (c) 2012 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 "http2.h"
+
+#include "util.h"
+
+namespace nghttp2 {
+
+namespace http2 {
+
+const char* get_status_string(int status_code)
+{
+  switch(status_code) {
+  case 100: return "100 Continue";
+  case 101: return "101 Switching Protocols";
+  case 200: return "200 OK";
+  case 201: return "201 Created";
+  case 202: return "202 Accepted";
+  case 203: return "203 Non-Authoritative Information";
+  case 204: return "204 No Content";
+  case 205: return "205 Reset Content";
+  case 206: return "206 Partial Content";
+  case 300: return "300 Multiple Choices";
+  case 301: return "301 Moved Permanently";
+  case 302: return "302 Found";
+  case 303: return "303 See Other";
+  case 304: return "304 Not Modified";
+  case 305: return "305 Use Proxy";
+    // case 306: return "306 (Unused)";
+  case 307: return "307 Temporary Redirect";
+  case 400: return "400 Bad Request";
+  case 401: return "401 Unauthorized";
+  case 402: return "402 Payment Required";
+  case 403: return "403 Forbidden";
+  case 404: return "404 Not Found";
+  case 405: return "405 Method Not Allowed";
+  case 406: return "406 Not Acceptable";
+  case 407: return "407 Proxy Authentication Required";
+  case 408: return "408 Request Timeout";
+  case 409: return "409 Conflict";
+  case 410: return "410 Gone";
+  case 411: return "411 Length Required";
+  case 412: return "412 Precondition Failed";
+  case 413: return "413 Request Entity Too Large";
+  case 414: return "414 Request-URI Too Long";
+  case 415: return "415 Unsupported Media Type";
+  case 416: return "416 Requested Range Not Satisfiable";
+  case 417: return "417 Expectation Failed";
+  case 500: return "500 Internal Server Error";
+  case 501: return "501 Not Implemented";
+  case 502: return "502 Bad Gateway";
+  case 503: return "503 Service Unavailable";
+  case 504: return "504 Gateway Timeout";
+  case 505: return "505 HTTP Version Not Supported";
+  default: return "";
+  }
+}
+
+void capitalize(std::string& s, size_t offset)
+{
+  s[offset] = util::upcase(s[offset]);
+  for(size_t i = offset+1, eoi = s.size(); i < eoi; ++i) {
+    if(s[i-1] == '-') {
+      s[i] = util::upcase(s[i]);
+    } else {
+      s[i] = util::lowcase(s[i]);
+    }
+  }
+}
+
+void sanitize_header_value(std::string& s, size_t offset)
+{
+  for(size_t i = offset, eoi = s.size(); i < eoi; ++i) {
+    if(s[i] == '\r' || s[i] == '\n') {
+      s[i] = ' ';
+    }
+  }
+}
+
+void copy_url_component(std::string& dest, http_parser_url *u, int field,
+                        const char* url)
+{
+  if(u->field_set & (1 << field)) {
+    dest.assign(url+u->field_data[field].off, u->field_data[field].len);
+  }
+}
+
+bool check_http2_allowed_header(const char *name)
+{
+  return check_http2_allowed_header(reinterpret_cast<const uint8_t*>(name),
+                                    strlen(name));
+}
+
+bool check_http2_allowed_header(const uint8_t *name, size_t namelen)
+{
+  return
+    !util::strieq("connection", name, namelen) &&
+    !util::strieq("host", name, namelen) &&
+    !util::strieq("keep-alive", name, namelen) &&
+    !util::strieq("proxy-connection", name, namelen) &&
+    !util::strieq("te", name, namelen) &&
+    !util::strieq("transfer-encoding", name, namelen) &&
+    !util::strieq("upgrade", name, namelen);
+}
+
+namespace {
+const char *DISALLOWED_HD[] = {
+  "connection",
+  "host",
+  "keep-alive",
+  "proxy-connection",
+  "te",
+  "transfer-encoding",
+  "upgrade",
+};
+} // namespace
+
+namespace {
+size_t DISALLOWED_HDLEN = sizeof(DISALLOWED_HD)/sizeof(DISALLOWED_HD[0]);
+} // namespace
+
+namespace {
+const char *IGN_HD[] = {
+  "connection",
+  "expect",
+  "host",
+  "http2-settings",
+  "keep-alive",
+  "proxy-connection",
+  "te",
+  "transfer-encoding",
+  "upgrade",
+  "via",
+  "x-forwarded-for",
+  "x-forwarded-proto",
+};
+} // namespace
+
+namespace {
+size_t IGN_HDLEN = sizeof(IGN_HD)/sizeof(IGN_HD[0]);
+} // namespace
+
+namespace {
+const char *HTTP1_IGN_HD[] = {
+  "connection",
+  "expect",
+  "http2-settings",
+  "keep-alive",
+  "proxy-connection",
+  "upgrade",
+  "via",
+  "x-forwarded-for",
+  "x-forwarded-proto",
+};
+} // namespace
+
+namespace {
+size_t HTTP1_IGN_HDLEN = sizeof(HTTP1_IGN_HD)/sizeof(HTTP1_IGN_HD[0]);
+} // namespace
+
+namespace {
+auto nv_name_less = [](const nghttp2_nv& lhs, const nghttp2_nv& rhs)
+{
+  return nghttp2_nv_compare_name(&lhs, &rhs) < 0;
+};
+} // namespace
+
+bool check_http2_headers(const nghttp2_nv *nva, size_t nvlen)
+{
+  for(size_t i = 0; i < DISALLOWED_HDLEN; ++i) {
+    nghttp2_nv nv = {(uint8_t*)DISALLOWED_HD[i], nullptr,
+                     (uint16_t)strlen(DISALLOWED_HD[i]), 0};
+    if(std::binary_search(&nva[0], &nva[nvlen], nv, nv_name_less)) {
+      return false;
+    }
+  }
+  return true;
+}
+
+const nghttp2_nv* get_unique_header(const nghttp2_nv *nva, size_t nvlen,
+                                    const char *name)
+{
+  size_t namelen = strlen(name);
+  nghttp2_nv nv = {(uint8_t*)name, nullptr, (uint16_t)namelen, 0};
+  auto i = std::lower_bound(&nva[0], &nva[nvlen], nv, nv_name_less);
+  if(i != &nva[nvlen] && util::streq(i->name, i->namelen,
+                                     (const uint8_t*)name, namelen)) {
+    auto j = i + 1;
+    if(j == &nva[nvlen] || !util::streq(j->name, j->namelen,
+                                        (const uint8_t*)name, namelen)) {
+      return i;
+    }
+  }
+  return nullptr;
+}
+
+const nghttp2_nv* get_header(const nghttp2_nv *nva, size_t nvlen,
+                             const char *name)
+{
+  size_t namelen = strlen(name);
+  nghttp2_nv nv = {(uint8_t*)name, nullptr, (uint16_t)namelen, 0};
+  auto i = std::lower_bound(&nva[0], &nva[nvlen], nv, nv_name_less);
+  if(i != &nva[nvlen] && util::streq(i->name, i->namelen,
+                                     (const uint8_t*)name, namelen)) {
+    return i;
+  }
+  return nullptr;
+}
+
+std::string name_to_str(const nghttp2_nv *nv)
+{
+  return std::string(reinterpret_cast<const char*>(nv->name), nv->namelen);
+}
+
+std::string value_to_str(const nghttp2_nv *nv)
+{
+  return std::string(reinterpret_cast<const char*>(nv->value), nv->valuelen);
+}
+
+bool value_lws(const nghttp2_nv *nv)
+{
+  for(size_t i = 0; i < nv->valuelen; ++i) {
+    switch(nv->value[i]) {
+    case '\t':
+    case ' ':
+      continue;
+    default:
+      return false;
+    }
+  }
+  return true;
+}
+
+size_t copy_norm_headers_to_nv
+(const char **nv,
+ const std::vector<std::pair<std::string, std::string>>& headers)
+{
+  size_t i, j, nvlen = 0;
+  for(i = 0, j = 0; i < headers.size() && j < IGN_HDLEN;) {
+    int rv = strcmp(headers[i].first.c_str(), IGN_HD[j]);
+    if(rv < 0) {
+      nv[nvlen++] = headers[i].first.c_str();
+      nv[nvlen++] = headers[i].second.c_str();
+      ++i;
+    } else if(rv > 0) {
+      ++j;
+    } else {
+      ++i;
+    }
+  }
+  for(; i < headers.size(); ++i) {
+    nv[nvlen++] = headers[i].first.c_str();
+    nv[nvlen++] = headers[i].second.c_str();
+  }
+  return nvlen;
+}
+
+void build_http1_headers_from_norm_headers
+(std::string& hdrs,
+ const std::vector<std::pair<std::string,
+ std::string>>& headers)
+{
+  size_t i, j;
+  for(i = 0, j = 0; i < headers.size() && j < HTTP1_IGN_HDLEN;) {
+    int rv = strcmp(headers[i].first.c_str(), HTTP1_IGN_HD[j]);
+    if(rv < 0) {
+      hdrs += headers[i].first;
+      capitalize(hdrs, hdrs.size()-headers[i].first.size());
+      hdrs += ": ";
+      hdrs += headers[i].second;
+      hdrs += "\r\n";
+      ++i;
+    } else if(rv > 0) {
+      ++j;
+    } else {
+      ++i;
+    }
+  }
+  for(; i < headers.size(); ++i) {
+    hdrs += headers[i].first;
+    capitalize(hdrs, hdrs.size()-headers[i].first.size());
+    hdrs += ": ";
+    hdrs += headers[i].second;
+    hdrs += "\r\n";
+  }
+}
+
+} // namespace http2
+
+} // namespace nghttp2
diff --git a/src/http2.h b/src/http2.h
new file mode 100644
index 00000000..77d8de68
--- /dev/null
+++ b/src/http2.h
@@ -0,0 +1,104 @@
+/*
+ * nghttp2 - HTTP/2.0 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.
+ */
+#ifndef HTTP2_H
+#define HTTP2_H
+
+#include "nghttp2_config.h"
+
+#include <string>
+#include <vector>
+
+#include <nghttp2/nghttp2.h>
+
+#include "http-parser/http_parser.h"
+
+namespace nghttp2 {
+
+namespace http2 {
+
+const char* get_status_string(int status_code);
+
+void capitalize(std::string& s, size_t offset);
+
+void sanitize_header_value(std::string& s, size_t offset);
+
+// Copies the |field| component value from |u| and |url| to the
+// |dest|. If |u| does not have |field|, then this function does
+// nothing.
+void copy_url_component(std::string& dest, http_parser_url *u, int field,
+                        const char* url);
+
+// Returns true if the header field |name| with length |namelen| bytes
+// is valid for HTTP/2.0.
+bool check_http2_allowed_header(const uint8_t *name, size_t namelen);
+
+// Calls check_http2_allowed_header with |name| and strlen(name),
+// assuming |name| is null-terminated string.
+bool check_http2_allowed_header(const char *name);
+
+// Checks that headers |nva| including |nvlen| entries do not contain
+// disallowed header fields in HTTP/2.0 spec. This function returns
+// true if |nva| does not contains such headers.
+bool check_http2_headers(const nghttp2_nv *nva, size_t nvlen);
+
+// Returns the pointer to the entry in |nva| which has name |name| and
+// the |name| is uinque in the |nva|. If no such entry exist, returns
+// nullptr.
+const nghttp2_nv* get_unique_header(const nghttp2_nv *nva, size_t nvlen,
+                                    const char *name);
+
+// Returns the poiter to the entry in |nva| which has name |name|. If
+// more than one entries which have the name |name|, first occurrence
+// in |nva| is returned. If no such entry exist, returns nullptr.
+const nghttp2_nv* get_header(const nghttp2_nv *nva, size_t nvlen,
+                             const char *name);
+
+// Returns std::string version of nv->name with nv->namelen bytes.
+std::string name_to_str(const nghttp2_nv *nv);
+// Returns std::string version of nv->value with nv->valuelen bytes.
+std::string value_to_str(const nghttp2_nv *nv);
+
+// Returns true if the value of |nv| includes only ' ' (0x20) or '\t'.
+bool value_lws(const nghttp2_nv *nv);
+
+// Copies headers in |headers| to |nv|. Certain headers, including
+// disallowed headers in HTTP/2.0 spec and headers which require
+// special handling (i.e. via), are not copied.
+size_t copy_norm_headers_to_nv
+(const char **nv,
+ const std::vector<std::pair<std::string, std::string>>& headers);
+
+// Appends HTTP/1.1 style header lines to |hdrs| from headers in
+// |headers|. Certain headers, which requires special handling
+// (i.e. via), are not appended.
+void build_http1_headers_from_norm_headers
+(std::string& hdrs,
+ const std::vector<std::pair<std::string, std::string>>& headers);
+
+} // namespace http2
+
+} // namespace nghttp2
+
+#endif // HTTP2_H
diff --git a/src/shrpx_http_test.cc b/src/http2_test.cc
similarity index 79%
rename from src/shrpx_http_test.cc
rename to src/http2_test.cc
index d6f6ef73..aaf59926 100644
--- a/src/shrpx_http_test.cc
+++ b/src/http2_test.cc
@@ -22,13 +22,13 @@
  * 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_http_test.h"
+#include "http2_test.h"
 
 #include <iostream>
 
 #include <CUnit/CUnit.h>
 
-#include "shrpx_http.h"
+#include "http2.h"
 #include "util.h"
 
 using namespace nghttp2;
@@ -37,25 +37,25 @@ using namespace nghttp2;
 
 namespace shrpx {
 
-void test_http_check_http2_headers(void)
+void test_http2_check_http2_headers(void)
 {
   nghttp2_nv nv1[] = {MAKE_NV("alpha", "1"),
                       MAKE_NV("bravo", "2"),
                       MAKE_NV("upgrade", "http2")};
-  CU_ASSERT(!http::check_http2_headers(nv1, 3));
+  CU_ASSERT(!http2::check_http2_headers(nv1, 3));
 
   nghttp2_nv nv2[] = {MAKE_NV("connection", "1"),
                       MAKE_NV("delta", "2"),
                       MAKE_NV("echo", "3")};
-  CU_ASSERT(!http::check_http2_headers(nv2, 3));
+  CU_ASSERT(!http2::check_http2_headers(nv2, 3));
 
   nghttp2_nv nv3[] = {MAKE_NV("alpha", "1"),
                       MAKE_NV("bravo", "2"),
                       MAKE_NV("te2", "3")};
-  CU_ASSERT(http::check_http2_headers(nv3, 3));
+  CU_ASSERT(http2::check_http2_headers(nv3, 3));
 }
 
-void test_http_get_unique_header(void)
+void test_http2_get_unique_header(void)
 {
   nghttp2_nv nv[] = {MAKE_NV("alpha", "1"),
                      MAKE_NV("bravo", "2"),
@@ -65,18 +65,18 @@ void test_http_get_unique_header(void)
                      MAKE_NV("echo", "6"),};
   size_t nvlen = sizeof(nv)/sizeof(nv[0]);
   const nghttp2_nv *rv;
-  rv = http::get_unique_header(nv, nvlen, "delta");
+  rv = http2::get_unique_header(nv, nvlen, "delta");
   CU_ASSERT(rv != nullptr);
   CU_ASSERT(util::streq("delta", rv->name, rv->namelen));
 
-  rv = http::get_unique_header(nv, nvlen, "bravo");
+  rv = http2::get_unique_header(nv, nvlen, "bravo");
   CU_ASSERT(rv == nullptr);
 
-  rv = http::get_unique_header(nv, nvlen, "foxtrot");
+  rv = http2::get_unique_header(nv, nvlen, "foxtrot");
   CU_ASSERT(rv == nullptr);
 }
 
-void test_http_get_header(void)
+void test_http2_get_header(void)
 {
   nghttp2_nv nv[] = {MAKE_NV("alpha", "1"),
                      MAKE_NV("bravo", "2"),
@@ -86,30 +86,30 @@ void test_http_get_header(void)
                      MAKE_NV("echo", "6"),};
   size_t nvlen = sizeof(nv)/sizeof(nv[0]);
   const nghttp2_nv *rv;
-  rv = http::get_header(nv, nvlen, "delta");
+  rv = http2::get_header(nv, nvlen, "delta");
   CU_ASSERT(rv != nullptr);
   CU_ASSERT(util::streq("delta", rv->name, rv->namelen));
 
-  rv = http::get_header(nv, nvlen, "bravo");
+  rv = http2::get_header(nv, nvlen, "bravo");
   CU_ASSERT(rv != nullptr);
   CU_ASSERT(util::streq("bravo", rv->name, rv->namelen));
 
-  rv = http::get_header(nv, nvlen, "foxtrot");
+  rv = http2::get_header(nv, nvlen, "foxtrot");
   CU_ASSERT(rv == nullptr);
 }
 
-void test_http_value_lws(void)
+void test_http2_value_lws(void)
 {
   nghttp2_nv nv[] = {MAKE_NV("0", "alpha"),
                      MAKE_NV("1", " alpha"),
                      MAKE_NV("2", ""),
                      MAKE_NV("3", " "),
                      MAKE_NV("4", "  a ")};
-  CU_ASSERT(!http::value_lws(&nv[0]));
-  CU_ASSERT(!http::value_lws(&nv[1]));
-  CU_ASSERT(http::value_lws(&nv[2]));
-  CU_ASSERT(http::value_lws(&nv[3]));
-  CU_ASSERT(!http::value_lws(&nv[4]));
+  CU_ASSERT(!http2::value_lws(&nv[0]));
+  CU_ASSERT(!http2::value_lws(&nv[1]));
+  CU_ASSERT(http2::value_lws(&nv[2]));
+  CU_ASSERT(http2::value_lws(&nv[3]));
+  CU_ASSERT(!http2::value_lws(&nv[4]));
 }
 
 namespace {
@@ -129,10 +129,10 @@ auto headers = std::vector<std::pair<std::string, std::string>>
    {"zulu", "12"}};
 } // namespace
 
-void test_http_copy_norm_headers_to_nv(void)
+void test_http2_copy_norm_headers_to_nv(void)
 {
   const char* nv[30];
-  size_t nvlen = http::copy_norm_headers_to_nv(nv, headers);
+  size_t nvlen = http2::copy_norm_headers_to_nv(nv, headers);
   CU_ASSERT(12 == nvlen);
   CU_ASSERT(strcmp(nv[0], "alpha") == 0);
   CU_ASSERT(strcmp(nv[1], "0") == 0);
@@ -148,10 +148,10 @@ void test_http_copy_norm_headers_to_nv(void)
   CU_ASSERT(strcmp(nv[11], "12") == 0);
 }
 
-void test_http_build_http1_headers_from_norm_headers(void)
+void test_http2_build_http1_headers_from_norm_headers(void)
 {
   std::string hdrs;
-  http::build_http1_headers_from_norm_headers(hdrs, headers);
+  http2::build_http1_headers_from_norm_headers(hdrs, headers);
   CU_ASSERT(hdrs ==
             "Alpha: 0\r\n"
             "Bravo: 1\r\n"
diff --git a/src/shrpx_http_test.h b/src/http2_test.h
similarity index 77%
rename from src/shrpx_http_test.h
rename to src/http2_test.h
index 9f8fa9b5..488b923a 100644
--- a/src/shrpx_http_test.h
+++ b/src/http2_test.h
@@ -22,18 +22,18 @@
  * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  */
-#ifndef SHRPX_HTTP_TEST_H
-#define SHRPX_HTTP_TEST_H
+#ifndef SHRPX_HTTP2_TEST_H
+#define SHRPX_HTTP2_TEST_H
 
 namespace shrpx {
 
-void test_http_check_http2_headers(void);
-void test_http_get_unique_header(void);
-void test_http_get_header(void);
-void test_http_value_lws(void);
-void test_http_copy_norm_headers_to_nv(void);
-void test_http_build_http1_headers_from_norm_headers(void);
+void test_http2_check_http2_headers(void);
+void test_http2_get_unique_header(void);
+void test_http2_get_header(void);
+void test_http2_value_lws(void);
+void test_http2_copy_norm_headers_to_nv(void);
+void test_http2_build_http1_headers_from_norm_headers(void);
 
 } // namespace shrpx
 
-#endif // SHRPX_HTTP_TEST_H
+#endif // SHRPX_HTTP2_TEST_H
diff --git a/src/shrpx-unittest.cc b/src/shrpx-unittest.cc
index 8d78f23e..74b90387 100644
--- a/src/shrpx-unittest.cc
+++ b/src/shrpx-unittest.cc
@@ -29,8 +29,8 @@
 #include <openssl/err.h>
 /* include test cases' include files here */
 #include "shrpx_ssl_test.h"
-#include "shrpx_http_test.h"
 #include "shrpx_downstream_test.h"
+#include "http2_test.h"
 #include "util_test.h"
 
 static int init_suite1(void)
@@ -69,18 +69,18 @@ int main(int argc, char* argv[])
                    shrpx::test_shrpx_ssl_create_lookup_tree) ||
       !CU_add_test(pSuite, "ssl_cert_lookup_tree_add_cert_from_file",
                    shrpx::test_shrpx_ssl_cert_lookup_tree_add_cert_from_file) ||
-      !CU_add_test(pSuite, "http_check_http2_headers",
-                   shrpx::test_http_check_http2_headers) ||
-      !CU_add_test(pSuite, "http_get_unique_header",
-                   shrpx::test_http_get_unique_header) ||
-      !CU_add_test(pSuite, "http_get_header",
-                   shrpx::test_http_get_header) ||
-      !CU_add_test(pSuite, "http_value_lws",
-                   shrpx::test_http_value_lws) ||
-      !CU_add_test(pSuite, "http_copy_norm_headers_to_nv",
-                   shrpx::test_http_copy_norm_headers_to_nv) ||
-      !CU_add_test(pSuite, "http_build_http1_headers_from_norm_headers",
-                   shrpx::test_http_build_http1_headers_from_norm_headers) ||
+      !CU_add_test(pSuite, "http2_check_http2_headers",
+                   shrpx::test_http2_check_http2_headers) ||
+      !CU_add_test(pSuite, "http2_get_unique_header",
+                   shrpx::test_http2_get_unique_header) ||
+      !CU_add_test(pSuite, "http2_get_header",
+                   shrpx::test_http2_get_header) ||
+      !CU_add_test(pSuite, "http2_value_lws",
+                   shrpx::test_http2_value_lws) ||
+      !CU_add_test(pSuite, "http2_copy_norm_headers_to_nv",
+                   shrpx::test_http2_copy_norm_headers_to_nv) ||
+      !CU_add_test(pSuite, "http2_build_http1_headers_from_norm_headers",
+                   shrpx::test_http2_build_http1_headers_from_norm_headers) ||
       !CU_add_test(pSuite, "downstream_normalize_request_headers",
                    shrpx::test_downstream_normalize_request_headers) ||
       !CU_add_test(pSuite, "downstream_normalize_response_headers",
diff --git a/src/shrpx_config.cc b/src/shrpx_config.cc
index ee67dd99..b7f057fb 100644
--- a/src/shrpx_config.cc
+++ b/src/shrpx_config.cc
@@ -38,9 +38,12 @@
 
 #include <nghttp2/nghttp2.h>
 
+#include "http-parser/http_parser.h"
+
 #include "shrpx_log.h"
 #include "shrpx_ssl.h"
 #include "shrpx_http.h"
+#include "http2.h"
 #include "util.h"
 
 using namespace nghttp2;
@@ -341,7 +344,7 @@ int parse_config(const char *opt, const char *optarg)
     if(rv == 0) {
       std::string val;
       if(u.field_set & UF_USERINFO) {
-        http::copy_url_component(val, &u, UF_USERINFO, optarg);
+        http2::copy_url_component(val, &u, UF_USERINFO, optarg);
         // Surprisingly, u.field_set & UF_USERINFO is nonzero even if
         // userinfo component is empty string.
         if(!val.empty()) {
@@ -351,7 +354,7 @@ int parse_config(const char *opt, const char *optarg)
         }
       }
       if(u.field_set & UF_HOST) {
-        http::copy_url_component(val, &u, UF_HOST, optarg);
+        http2::copy_url_component(val, &u, UF_HOST, optarg);
         set_config_str(&mod_config()->downstream_http_proxy_host, val.c_str());
       } else {
         LOG(ERROR) << "backend-http-proxy-uri does not contain hostname";
diff --git a/src/shrpx_http.cc b/src/shrpx_http.cc
index eefde0c2..d825b183 100644
--- a/src/shrpx_http.cc
+++ b/src/shrpx_http.cc
@@ -26,6 +26,7 @@
 
 #include "shrpx_config.h"
 #include "shrpx_log.h"
+#include "http2.h"
 #include "util.h"
 
 using namespace nghttp2;
@@ -34,59 +35,11 @@ namespace shrpx {
 
 namespace http {
 
-const char* get_status_string(int status_code)
-{
-  switch(status_code) {
-  case 100: return "100 Continue";
-  case 101: return "101 Switching Protocols";
-  case 200: return "200 OK";
-  case 201: return "201 Created";
-  case 202: return "202 Accepted";
-  case 203: return "203 Non-Authoritative Information";
-  case 204: return "204 No Content";
-  case 205: return "205 Reset Content";
-  case 206: return "206 Partial Content";
-  case 300: return "300 Multiple Choices";
-  case 301: return "301 Moved Permanently";
-  case 302: return "302 Found";
-  case 303: return "303 See Other";
-  case 304: return "304 Not Modified";
-  case 305: return "305 Use Proxy";
-    // case 306: return "306 (Unused)";
-  case 307: return "307 Temporary Redirect";
-  case 400: return "400 Bad Request";
-  case 401: return "401 Unauthorized";
-  case 402: return "402 Payment Required";
-  case 403: return "403 Forbidden";
-  case 404: return "404 Not Found";
-  case 405: return "405 Method Not Allowed";
-  case 406: return "406 Not Acceptable";
-  case 407: return "407 Proxy Authentication Required";
-  case 408: return "408 Request Timeout";
-  case 409: return "409 Conflict";
-  case 410: return "410 Gone";
-  case 411: return "411 Length Required";
-  case 412: return "412 Precondition Failed";
-  case 413: return "413 Request Entity Too Large";
-  case 414: return "414 Request-URI Too Long";
-  case 415: return "415 Unsupported Media Type";
-  case 416: return "416 Requested Range Not Satisfiable";
-  case 417: return "417 Expectation Failed";
-  case 500: return "500 Internal Server Error";
-  case 501: return "501 Not Implemented";
-  case 502: return "502 Bad Gateway";
-  case 503: return "503 Service Unavailable";
-  case 504: return "504 Gateway Timeout";
-  case 505: return "505 HTTP Version Not Supported";
-  default: return "";
-  }
-}
-
 std::string create_error_html(int status_code)
 {
   std::string res;
   res.reserve(512);
-  const char *status = http::get_status_string(status_code);
+  const char *status = http2::get_status_string(status_code);
   res += "<html><head><title>";
   res += status;
   res += "</title></head><body><h1>";
@@ -110,27 +63,6 @@ std::string create_via_header_value(int major, int minor)
   return hdrs;
 }
 
-void capitalize(std::string& s, size_t offset)
-{
-  s[offset] = util::upcase(s[offset]);
-  for(size_t i = offset+1, eoi = s.size(); i < eoi; ++i) {
-    if(s[i-1] == '-') {
-      s[i] = util::upcase(s[i]);
-    } else {
-      s[i] = util::lowcase(s[i]);
-    }
-  }
-}
-
-void sanitize_header_value(std::string& s, size_t offset)
-{
-  for(size_t i = offset, eoi = s.size(); i < eoi; ++i) {
-    if(s[i] == '\r' || s[i] == '\n') {
-      s[i] = ' ';
-    }
-  }
-}
-
 std::string colorizeHeaders(const char *hdrs)
 {
   std::string nhdrs;
@@ -162,214 +94,6 @@ std::string colorizeHeaders(const char *hdrs)
   return nhdrs;
 }
 
-void copy_url_component(std::string& dest, http_parser_url *u, int field,
-                        const char* url)
-{
-  if(u->field_set & (1 << field)) {
-    dest.assign(url+u->field_data[field].off, u->field_data[field].len);
-  }
-}
-
-bool check_http2_allowed_header(const char *name)
-{
-  return check_http2_allowed_header(reinterpret_cast<const uint8_t*>(name),
-                                    strlen(name));
-}
-
-bool check_http2_allowed_header(const uint8_t *name, size_t namelen)
-{
-  return
-    !util::strieq("connection", name, namelen) &&
-    !util::strieq("host", name, namelen) &&
-    !util::strieq("keep-alive", name, namelen) &&
-    !util::strieq("proxy-connection", name, namelen) &&
-    !util::strieq("te", name, namelen) &&
-    !util::strieq("transfer-encoding", name, namelen) &&
-    !util::strieq("upgrade", name, namelen);
-}
-
-namespace {
-const char *DISALLOWED_HD[] = {
-  "connection",
-  "host",
-  "keep-alive",
-  "proxy-connection",
-  "te",
-  "transfer-encoding",
-  "upgrade",
-};
-} // namespace
-
-namespace {
-size_t DISALLOWED_HDLEN = sizeof(DISALLOWED_HD)/sizeof(DISALLOWED_HD[0]);
-} // namespace
-
-namespace {
-const char *IGN_HD[] = {
-  "connection",
-  "expect",
-  "host",
-  "http2-settings",
-  "keep-alive",
-  "proxy-connection",
-  "te",
-  "transfer-encoding",
-  "upgrade",
-  "via",
-  "x-forwarded-for",
-  "x-forwarded-proto",
-};
-} // namespace
-
-namespace {
-size_t IGN_HDLEN = sizeof(IGN_HD)/sizeof(IGN_HD[0]);
-} // namespace
-
-namespace {
-const char *HTTP1_IGN_HD[] = {
-  "connection",
-  "expect",
-  "http2-settings",
-  "keep-alive",
-  "proxy-connection",
-  "upgrade",
-  "via",
-  "x-forwarded-for",
-  "x-forwarded-proto",
-};
-} // namespace
-
-namespace {
-size_t HTTP1_IGN_HDLEN = sizeof(HTTP1_IGN_HD)/sizeof(HTTP1_IGN_HD[0]);
-} // namespace
-
-namespace {
-auto nv_name_less = [](const nghttp2_nv& lhs, const nghttp2_nv& rhs)
-{
-  return nghttp2_nv_compare_name(&lhs, &rhs) < 0;
-};
-} // namespace
-
-bool check_http2_headers(const nghttp2_nv *nva, size_t nvlen)
-{
-  for(size_t i = 0; i < DISALLOWED_HDLEN; ++i) {
-    nghttp2_nv nv = {(uint8_t*)DISALLOWED_HD[i], nullptr,
-                     (uint16_t)strlen(DISALLOWED_HD[i]), 0};
-    if(std::binary_search(&nva[0], &nva[nvlen], nv, nv_name_less)) {
-      return false;
-    }
-  }
-  return true;
-}
-
-const nghttp2_nv* get_unique_header(const nghttp2_nv *nva, size_t nvlen,
-                                    const char *name)
-{
-  size_t namelen = strlen(name);
-  nghttp2_nv nv = {(uint8_t*)name, nullptr, (uint16_t)namelen, 0};
-  auto i = std::lower_bound(&nva[0], &nva[nvlen], nv, nv_name_less);
-  if(i != &nva[nvlen] && util::streq(i->name, i->namelen,
-                                     (const uint8_t*)name, namelen)) {
-    auto j = i + 1;
-    if(j == &nva[nvlen] || !util::streq(j->name, j->namelen,
-                                        (const uint8_t*)name, namelen)) {
-      return i;
-    }
-  }
-  return nullptr;
-}
-
-const nghttp2_nv* get_header(const nghttp2_nv *nva, size_t nvlen,
-                             const char *name)
-{
-  size_t namelen = strlen(name);
-  nghttp2_nv nv = {(uint8_t*)name, nullptr, (uint16_t)namelen, 0};
-  auto i = std::lower_bound(&nva[0], &nva[nvlen], nv, nv_name_less);
-  if(i != &nva[nvlen] && util::streq(i->name, i->namelen,
-                                     (const uint8_t*)name, namelen)) {
-    return i;
-  }
-  return nullptr;
-}
-
-std::string name_to_str(const nghttp2_nv *nv)
-{
-  return std::string(reinterpret_cast<const char*>(nv->name), nv->namelen);
-}
-
-std::string value_to_str(const nghttp2_nv *nv)
-{
-  return std::string(reinterpret_cast<const char*>(nv->value), nv->valuelen);
-}
-
-bool value_lws(const nghttp2_nv *nv)
-{
-  for(size_t i = 0; i < nv->valuelen; ++i) {
-    switch(nv->value[i]) {
-    case '\t':
-    case ' ':
-      continue;
-    default:
-      return false;
-    }
-  }
-  return true;
-}
-
-size_t copy_norm_headers_to_nv
-(const char **nv,
- const std::vector<std::pair<std::string, std::string>>& headers)
-{
-  size_t i, j, nvlen = 0;
-  for(i = 0, j = 0; i < headers.size() && j < IGN_HDLEN;) {
-    int rv = strcmp(headers[i].first.c_str(), IGN_HD[j]);
-    if(rv < 0) {
-      nv[nvlen++] = headers[i].first.c_str();
-      nv[nvlen++] = headers[i].second.c_str();
-      ++i;
-    } else if(rv > 0) {
-      ++j;
-    } else {
-      ++i;
-    }
-  }
-  for(; i < headers.size(); ++i) {
-    nv[nvlen++] = headers[i].first.c_str();
-    nv[nvlen++] = headers[i].second.c_str();
-  }
-  return nvlen;
-}
-
-void build_http1_headers_from_norm_headers
-(std::string& hdrs,
- const std::vector<std::pair<std::string,
- std::string>>& headers)
-{
-  size_t i, j;
-  for(i = 0, j = 0; i < headers.size() && j < HTTP1_IGN_HDLEN;) {
-    int rv = strcmp(headers[i].first.c_str(), HTTP1_IGN_HD[j]);
-    if(rv < 0) {
-      hdrs += headers[i].first;
-      http::capitalize(hdrs, hdrs.size()-headers[i].first.size());
-      hdrs += ": ";
-      hdrs += headers[i].second;
-      hdrs += "\r\n";
-      ++i;
-    } else if(rv > 0) {
-      ++j;
-    } else {
-      ++i;
-    }
-  }
-  for(; i < headers.size(); ++i) {
-    hdrs += headers[i].first;
-    http::capitalize(hdrs, hdrs.size()-headers[i].first.size());
-    hdrs += ": ";
-    hdrs += headers[i].second;
-    hdrs += "\r\n";
-  }
-}
-
 } // namespace http
 
 } // namespace shrpx
diff --git a/src/shrpx_http.h b/src/shrpx_http.h
index 3f2eff96..01bc91da 100644
--- a/src/shrpx_http.h
+++ b/src/shrpx_http.h
@@ -25,83 +25,21 @@
 #ifndef SHRPX_HTTP_H
 #define SHRPX_HTTP_H
 
+#include "shrpx.h"
+
 #include <string>
-#include <vector>
-
-#include <nghttp2/nghttp2.h>
-
-#include "http-parser/http_parser.h"
 
 namespace shrpx {
 
 namespace http {
 
-const char* get_status_string(int status_code);
-
 std::string create_error_html(int status_code);
 
 std::string create_via_header_value(int major, int minor);
 
-void capitalize(std::string& s, size_t offset);
-
-void sanitize_header_value(std::string& s, size_t offset);
-
 // Adds ANSI color codes to HTTP headers |hdrs|.
 std::string colorizeHeaders(const char *hdrs);
 
-// Copies the |field| component value from |u| and |url| to the
-// |dest|. If |u| does not have |field|, then this function does
-// nothing.
-void copy_url_component(std::string& dest, http_parser_url *u, int field,
-                        const char* url);
-
-// Returns true if the header field |name| with length |namelen| bytes
-// is valid for HTTP/2.0.
-bool check_http2_allowed_header(const uint8_t *name, size_t namelen);
-
-// Calls check_http2_allowed_header with |name| and strlen(name),
-// assuming |name| is null-terminated string.
-bool check_http2_allowed_header(const char *name);
-
-// Checks that headers |nva| including |nvlen| entries do not contain
-// disallowed header fields in HTTP/2.0 spec. This function returns
-// true if |nva| does not contains such headers.
-bool check_http2_headers(const nghttp2_nv *nva, size_t nvlen);
-
-// Returns the pointer to the entry in |nva| which has name |name| and
-// the |name| is uinque in the |nva|. If no such entry exist, returns
-// nullptr.
-const nghttp2_nv* get_unique_header(const nghttp2_nv *nva, size_t nvlen,
-                                    const char *name);
-
-// Returns the poiter to the entry in |nva| which has name |name|. If
-// more than one entries which have the name |name|, first occurrence
-// in |nva| is returned. If no such entry exist, returns nullptr.
-const nghttp2_nv* get_header(const nghttp2_nv *nva, size_t nvlen,
-                             const char *name);
-
-// Returns std::string version of nv->name with nv->namelen bytes.
-std::string name_to_str(const nghttp2_nv *nv);
-// Returns std::string version of nv->value with nv->valuelen bytes.
-std::string value_to_str(const nghttp2_nv *nv);
-
-// Returns true if the value of |nv| includes only ' ' (0x20) or '\t'.
-bool value_lws(const nghttp2_nv *nv);
-
-// Copies headers in |headers| to |nv|. Certain headers, including
-// disallowed headers in HTTP/2.0 spec and headers which require
-// special handling (i.e. via), are not copied.
-size_t copy_norm_headers_to_nv
-(const char **nv,
- const std::vector<std::pair<std::string, std::string>>& headers);
-
-// Appends HTTP/1.1 style header lines to |hdrs| from headers in
-// |headers|. Certain headers, which requires special handling
-// (i.e. via), are not appended.
-void build_http1_headers_from_norm_headers
-(std::string& hdrs,
- const std::vector<std::pair<std::string, std::string>>& headers);
-
 } // namespace http
 
 } // namespace shrpx
diff --git a/src/shrpx_http2_upstream.cc b/src/shrpx_http2_upstream.cc
index 25a807e8..b87ac819 100644
--- a/src/shrpx_http2_upstream.cc
+++ b/src/shrpx_http2_upstream.cc
@@ -36,6 +36,7 @@
 #include "shrpx_config.h"
 #include "shrpx_http.h"
 #include "shrpx_accesslog.h"
+#include "http2.h"
 #include "util.h"
 #include "base64.h"
 
@@ -209,35 +210,35 @@ void on_frame_recv_callback
     }
 
     // Assuming that nva is sorted by name.
-    if(!http::check_http2_headers(nva, nvlen)) {
+    if(!http2::check_http2_headers(nva, nvlen)) {
       upstream->rst_stream(downstream, NGHTTP2_PROTOCOL_ERROR);
       return;
     }
 
     for(size_t i = 0; i < nvlen; ++i) {
       if(nva[i].namelen > 0 && nva[i].name[0] != ':') {
-        downstream->add_request_header(http::name_to_str(&nva[i]),
-                                       http::value_to_str(&nva[i]));
+        downstream->add_request_header(http2::name_to_str(&nva[i]),
+                                       http2::value_to_str(&nva[i]));
       }
     }
 
-    auto host = http::get_unique_header(nva, nvlen, ":host");
-    auto path = http::get_unique_header(nva, nvlen, ":path");
-    auto method = http::get_unique_header(nva, nvlen, ":method");
-    auto scheme = http::get_unique_header(nva, nvlen, ":scheme");
+    auto host = http2::get_unique_header(nva, nvlen, ":host");
+    auto path = http2::get_unique_header(nva, nvlen, ":path");
+    auto method = http2::get_unique_header(nva, nvlen, ":method");
+    auto scheme = http2::get_unique_header(nva, nvlen, ":scheme");
     bool is_connect = method &&
       util::streq("CONNECT", method->value, method->valuelen);
     if(!host || !path || !method ||
-       http::value_lws(host) || http::value_lws(path) ||
-       http::value_lws(method) ||
-       (!is_connect && (!scheme || http::value_lws(scheme)))) {
+       http2::value_lws(host) || http2::value_lws(path) ||
+       http2::value_lws(method) ||
+       (!is_connect && (!scheme || http2::value_lws(scheme)))) {
       upstream->rst_stream(downstream, NGHTTP2_PROTOCOL_ERROR);
       return;
     }
     if(!is_connect &&
        (frame->hd.flags & NGHTTP2_FLAG_END_STREAM) == 0) {
-      auto content_length = http::get_header(nva, nvlen, "content-length");
-      if(!content_length || http::value_lws(content_length)) {
+      auto content_length = http2::get_header(nva, nvlen, "content-length");
+      if(!content_length || http2::value_lws(content_length)) {
         // If content-length is missing,
         // Downstream::push_upload_data_chunk will fail and
         upstream->rst_stream(downstream, NGHTTP2_PROTOCOL_ERROR);
@@ -245,22 +246,22 @@ void on_frame_recv_callback
       }
     }
 
-    downstream->set_request_method(http::value_to_str(method));
+    downstream->set_request_method(http2::value_to_str(method));
 
     // SpdyDownstreamConnection examines request path to find
     // scheme. We construct abs URI for spdy_bridge mode as well as
     // spdy_proxy mode.
     if((get_config()->spdy_proxy || get_config()->spdy_bridge) &&
        scheme && path->value[0] == '/') {
-      std::string reqpath(http::value_to_str(scheme));
+      std::string reqpath(http2::value_to_str(scheme));
       reqpath += "://";
-      reqpath += http::value_to_str(host);
-      reqpath += http::value_to_str(path);
+      reqpath += http2::value_to_str(host);
+      reqpath += http2::value_to_str(path);
       downstream->set_request_path(reqpath);
     } else {
-      downstream->set_request_path(http::value_to_str(path));
+      downstream->set_request_path(http2::value_to_str(path));
     }
-    downstream->add_request_header("host", http::value_to_str(host));
+    downstream->add_request_header("host", http2::value_to_str(host));
     downstream->check_upgrade_request();
 
     auto dconn = upstream->get_client_handler()->get_downstream_connection();
@@ -701,7 +702,7 @@ void spdy_downstream_eventcb(bufferevent *bev, short events, void *ptr)
 } // namespace
 
 int Http2Upstream::rst_stream(Downstream *downstream,
-                             nghttp2_error_code error_code)
+                              nghttp2_error_code error_code)
 {
   if(LOG_ENABLED(INFO)) {
     ULOG(INFO, this) << "RST_STREAM stream_id="
@@ -863,8 +864,8 @@ int Http2Upstream::on_downstream_header_complete(Downstream *downstream)
   nv[hdidx++] = ":status";
   nv[hdidx++] = response_status.c_str();
 
-  hdidx += http::copy_norm_headers_to_nv(&nv[hdidx],
-                                         downstream->get_response_headers());
+  hdidx += http2::copy_norm_headers_to_nv(&nv[hdidx],
+                                          downstream->get_response_headers());
   auto via = downstream->get_norm_response_header("via");
   if(get_config()->no_via) {
     if(via != end_headers) {
@@ -914,7 +915,7 @@ int Http2Upstream::on_downstream_header_complete(Downstream *downstream)
 // WARNING: Never call directly or indirectly nghttp2_session_send or
 // nghttp2_session_recv. These calls may delete downstream.
 int Http2Upstream::on_downstream_body(Downstream *downstream,
-                                     const uint8_t *data, size_t len)
+                                      const uint8_t *data, size_t len)
 {
   evbuffer *body = downstream->get_response_body_buf();
   int rv = evbuffer_add(body, data, len);
diff --git a/src/shrpx_http_downstream_connection.cc b/src/shrpx_http_downstream_connection.cc
index a79175cc..3a797eac 100644
--- a/src/shrpx_http_downstream_connection.cc
+++ b/src/shrpx_http_downstream_connection.cc
@@ -30,6 +30,7 @@
 #include "shrpx_config.h"
 #include "shrpx_error.h"
 #include "shrpx_http.h"
+#include "http2.h"
 #include "util.h"
 
 using namespace nghttp2;
@@ -120,7 +121,7 @@ int HttpDownstreamConnection::push_request_headers()
   hdrs += "HTTP/1.1\r\n";
   downstream_->normalize_request_headers();
   auto end_headers = std::end(downstream_->get_request_headers());
-  http::build_http1_headers_from_norm_headers
+  http2::build_http1_headers_from_norm_headers
     (hdrs, downstream_->get_request_headers());
 
   if(downstream_->get_request_connection_close()) {
diff --git a/src/shrpx_https_upstream.cc b/src/shrpx_https_upstream.cc
index 439488fd..3fd1dc05 100644
--- a/src/shrpx_https_upstream.cc
+++ b/src/shrpx_https_upstream.cc
@@ -36,6 +36,7 @@
 #include "shrpx_config.h"
 #include "shrpx_error.h"
 #include "shrpx_accesslog.h"
+#include "http2.h"
 #include "util.h"
 
 using namespace nghttp2;
@@ -583,7 +584,7 @@ int HttpsUpstream::error_reply(int status_code)
   std::string header;
   header.reserve(512);
   header += "HTTP/1.1 ";
-  header += http::get_status_string(status_code);
+  header += http2::get_status_string(status_code);
   header += "\r\nServer: ";
   header += get_config()->server_name;
   header += "\r\nContent-Length: ";
@@ -659,11 +660,11 @@ int HttpsUpstream::on_downstream_header_complete(Downstream *downstream)
            downstream->get_request_major(),
            downstream->get_request_minor());
   std::string hdrs = temp;
-  hdrs += http::get_status_string(downstream->get_response_http_status());
+  hdrs += http2::get_status_string(downstream->get_response_http_status());
   hdrs += "\r\n";
   downstream->normalize_response_headers();
   auto end_headers = std::end(downstream->get_response_headers());
-  http::build_http1_headers_from_norm_headers
+  http2::build_http1_headers_from_norm_headers
     (hdrs, downstream->get_response_headers());
 
   // We check downstream->get_response_connection_close() in case when
diff --git a/src/shrpx_spdy_downstream_connection.cc b/src/shrpx_spdy_downstream_connection.cc
index d166951d..84408734 100644
--- a/src/shrpx_spdy_downstream_connection.cc
+++ b/src/shrpx_spdy_downstream_connection.cc
@@ -39,6 +39,7 @@
 #include "shrpx_error.h"
 #include "shrpx_http.h"
 #include "shrpx_spdy_session.h"
+#include "http2.h"
 #include "util.h"
 
 using namespace nghttp2;
@@ -252,9 +253,9 @@ int SpdyDownstreamConnection::push_request_headers()
                                downstream_->get_request_path().size(),
                                0, &u);
     if(rv == 0) {
-      http::copy_url_component(scheme, &u, UF_SCHEMA, url);
-      http::copy_url_component(path, &u, UF_PATH, url);
-      http::copy_url_component(query, &u, UF_QUERY, url);
+      http2::copy_url_component(scheme, &u, UF_SCHEMA, url);
+      http2::copy_url_component(path, &u, UF_PATH, url);
+      http2::copy_url_component(query, &u, UF_QUERY, url);
       if(path.empty()) {
         path = "/";
       }
@@ -282,8 +283,8 @@ int SpdyDownstreamConnection::push_request_headers()
   nv[hdidx++] = ":method";
   nv[hdidx++] = downstream_->get_request_method().c_str();
 
-  hdidx += http::copy_norm_headers_to_nv(&nv[hdidx],
-                                         downstream_->get_request_headers());
+  hdidx += http2::copy_norm_headers_to_nv(&nv[hdidx],
+                                          downstream_->get_request_headers());
 
   auto host = downstream_->get_norm_request_header("host");
   if(host == end_headers) {
diff --git a/src/shrpx_spdy_session.cc b/src/shrpx_spdy_session.cc
index c768da41..702d4032 100644
--- a/src/shrpx_spdy_session.cc
+++ b/src/shrpx_spdy_session.cc
@@ -40,6 +40,7 @@
 #include "shrpx_client_handler.h"
 #include "shrpx_ssl.h"
 #include "shrpx_http.h"
+#include "http2.h"
 #include "util.h"
 #include "base64.h"
 
@@ -749,7 +750,7 @@ void on_frame_recv_callback
     auto nvlen = frame->headers.nvlen;
 
     // Assuming that nva is sorted by name.
-    if(!http::check_http2_headers(nva, nvlen)) {
+    if(!http2::check_http2_headers(nva, nvlen)) {
       nghttp2_submit_rst_stream(session, frame->hd.stream_id,
                                 NGHTTP2_PROTOCOL_ERROR);
       downstream->set_response_state(Downstream::MSG_RESET);
@@ -759,13 +760,13 @@ void on_frame_recv_callback
 
     for(size_t i = 0; i < nvlen; ++i) {
       if(nva[i].namelen > 0 && nva[i].name[0] != ':') {
-        downstream->add_response_header(http::name_to_str(&nva[i]),
-                                        http::value_to_str(&nva[i]));
+        downstream->add_response_header(http2::name_to_str(&nva[i]),
+                                        http2::value_to_str(&nva[i]));
       }
     }
 
-    auto status = http::get_unique_header(nva, nvlen, ":status");
-    if(!status || http::value_lws(status)) {
+    auto status = http2::get_unique_header(nva, nvlen, ":status");
+    if(!status || http2::value_lws(status)) {
       nghttp2_submit_rst_stream(session, frame->hd.stream_id,
                                 NGHTTP2_PROTOCOL_ERROR);
       downstream->set_response_state(Downstream::MSG_RESET);
@@ -773,14 +774,14 @@ void on_frame_recv_callback
       return;
     }
     downstream->set_response_http_status
-      (strtoul(http::value_to_str(status).c_str(), nullptr, 10));
+      (strtoul(http2::value_to_str(status).c_str(), nullptr, 10));
 
     // Just assume it is HTTP/1.1. But we really consider to say 2.0
     // here.
     downstream->set_response_major(1);
     downstream->set_response_minor(1);
 
-    auto content_length = http::get_header(nva, nvlen, "content-length");
+    auto content_length = http2::get_header(nva, nvlen, "content-length");
     if(!content_length && downstream->get_request_method() != "HEAD" &&
        downstream->get_request_method() != "CONNECT") {
       unsigned int status;
diff --git a/src/shrpx_spdy_upstream.cc b/src/shrpx_spdy_upstream.cc
index a13883ef..403140c3 100644
--- a/src/shrpx_spdy_upstream.cc
+++ b/src/shrpx_spdy_upstream.cc
@@ -37,6 +37,7 @@
 #include "shrpx_config.h"
 #include "shrpx_http.h"
 #include "shrpx_accesslog.h"
+#include "http2.h"
 #include "util.h"
 
 using namespace nghttp2;
@@ -740,7 +741,7 @@ int SpdyUpstream::error_reply(Downstream *downstream, int status_code)
   std::string content_length = util::utos(html.size());
 
   const char *nv[] = {
-    ":status", http::get_status_string(status_code),
+    ":status", http2::get_status_string(status_code),
     ":version", "http/1.1",
     "content-type", "text/html; charset=UTF-8",
     "server", get_config()->server_name,
@@ -810,7 +811,8 @@ int SpdyUpstream::on_downstream_header_complete(Downstream *downstream)
   size_t hdidx = 0;
   std::string via_value;
   nv[hdidx++] = ":status";
-  nv[hdidx++] = http::get_status_string(downstream->get_response_http_status());
+  nv[hdidx++] = http2::get_status_string
+    (downstream->get_response_http_status());
   nv[hdidx++] = ":version";
   nv[hdidx++] = "HTTP/1.1";
   for(Headers::const_iterator i = downstream->get_response_headers().begin();