Merge pull request #2 from tatsuhiro-t/master

pulling changes from master

Makefile.am

@@ -23,6 +23,11 @@
 SUBDIRS = lib third-party src examples python tests integration-tests \
 	doc contrib script
 
+# Now with python setuptools, make uninstall will leave many files we
+# cannot easily remove (e.g., easy-install.pth).  Disable it for
+# distcheck rule.
+AM_DISTCHECK_CONFIGURE_FLAGS = --disable-python-bindings
+
 ACLOCAL_AMFLAGS = -I m4
 
 dist_doc_DATA = README.rst

configure.ac

@@ -25,7 +25,7 @@ dnl Do not change user variables!
 dnl http://www.gnu.org/software/automake/manual/html_node/Flag-Variables-Ordering.html
 
 AC_PREREQ(2.61)
-AC_INIT([nghttp2], [1.0.6-DEV], [t-tujikawa@users.sourceforge.net])
+AC_INIT([nghttp2], [1.1.2-DEV], [t-tujikawa@users.sourceforge.net])
 AC_USE_SYSTEM_EXTENSIONS
 
 LT_PREREQ([2.2.6])
@@ -48,7 +48,7 @@ AC_CONFIG_HEADERS([config.h])
 dnl See versioning rule:
 dnl  http://www.gnu.org/software/libtool/manual/html_node/Updating-version-info.html
 AC_SUBST(LT_CURRENT, 14)
-AC_SUBST(LT_REVISION, 5)
+AC_SUBST(LT_REVISION, 6)
 AC_SUBST(LT_AGE, 0)
 
 major=`echo $PACKAGE_VERSION |cut -d. -f1 | sed -e "s/[^0-9]//g"`

doc/bash_completion/h2load

@@ -8,7 +8,7 @@ _h2load()
     _get_comp_words_by_ref cur prev
     case $cur in
         -*)
-            COMPREPLY=( $( compgen -W '--threads --connection-window-bits --input-file --help --requests --data --verbose --version --window-bits --clients --no-tls-proto --header --max-concurrent-streams ' -- "$cur" ) )
+            COMPREPLY=( $( compgen -W '--threads --connection-window-bits --input-file --help --requests --data --verbose --ciphers --window-bits --clients --no-tls-proto --version --header --max-concurrent-streams ' -- "$cur" ) )
             ;;
         *)
             _filedir

doc/bash_completion/nghttp

@@ -8,7 +8,7 @@ _nghttp()
     _get_comp_words_by_ref cur prev
     case $cur in
         -*)
-            COMPREPLY=( $( compgen -W '--no-push --verbose --no-dep --get-assets --har --header-table-size --multiply --padding --hexdump --continuation --connection-window-bits --peer-max-concurrent-streams --timeout --data --no-content-length --version --color --cert --upgrade --remote-name --trailer --weight --help --key --null-out --window-bits --stat --header ' -- "$cur" ) )
+            COMPREPLY=( $( compgen -W '--no-push --verbose --no-dep --get-assets --har --header-table-size --multiply --padding --hexdump --max-concurrent-streams --continuation --connection-window-bits --peer-max-concurrent-streams --timeout --data --no-content-length --version --color --cert --upgrade --remote-name --trailer --weight --help --key --null-out --window-bits --stat --header ' -- "$cur" ) )
             ;;
         *)
             _filedir

doc/bash_completion/nghttpx

@@ -8,7 +8,7 @@ _nghttpx()
     _get_comp_words_by_ref cur prev
     case $cur in
         -*)
-            COMPREPLY=( $( compgen -W '--worker-read-rate --frontend-no-tls --frontend-http2-dump-response-header --backend-http1-connections-per-frontend --tls-ticket-key-file --verify-client-cacert --backend-request-buffer --backend-http2-connection-window-bits --conf --worker-write-burst --npn-list --fetch-ocsp-response-file --stream-read-timeout --accesslog-syslog --frontend-http2-read-timeout --listener-disable-timeout --frontend-http2-connection-window-bits --ciphers --strip-incoming-x-forwarded-for --daemon --backend-keep-alive-timeout --backend-http-proxy-uri --backend-http1-connections-per-host --rlimit-nofile --no-via --ocsp-update-interval --backend-write-timeout --client --http2-no-cookie-crumbling --worker-read-burst --client-proxy --http2-bridge --accesslog-format --errorlog-syslog --errorlog-file --http2-max-concurrent-streams --frontend-write-timeout --read-burst --backend-ipv4 --backend-ipv6 --backend --insecure --log-level --tls-proto-list --backend-http2-connections-per-worker --dh-param-file --worker-frontend-connections --header-field-buffer --no-server-push --no-location-rewrite --no-ocsp --backend-response-buffer --workers --frontend-http2-window-bits --no-host-rewrite --worker-write-rate --add-request-header --backend-tls-sni-field --subcert --help --frontend-frame-debug --pid-file --frontend-http2-dump-request-header --private-key-passwd-file --write-rate --altsvc --user --add-x-forwarded-for --syslog-facility --frontend-read-timeout --backlog --write-burst --backend-http2-window-bits --padding --stream-write-timeout --cacert --version --verify-client --backend-read-timeout --frontend --accesslog-file --http2-proxy --max-header-fields --backend-no-tls --client-private-key-file --client-cert-file --add-response-header --read-rate ' -- "$cur" ) )
+            COMPREPLY=( $( compgen -W '--worker-read-rate --frontend-no-tls --frontend-http2-dump-response-header --backend-http1-connections-per-frontend --tls-ticket-key-file --verify-client-cacert --include --backend-request-buffer --backend-http2-connection-window-bits --conf --worker-write-burst --npn-list --fetch-ocsp-response-file --stream-read-timeout --accesslog-syslog --frontend-http2-read-timeout --listener-disable-timeout --frontend-http2-connection-window-bits --ciphers --strip-incoming-x-forwarded-for --daemon --backend-keep-alive-timeout --backend-http-proxy-uri --backend-http1-connections-per-host --rlimit-nofile --no-via --ocsp-update-interval --backend-write-timeout --client --http2-no-cookie-crumbling --worker-read-burst --client-proxy --http2-bridge --accesslog-format --errorlog-syslog --errorlog-file --http2-max-concurrent-streams --frontend-write-timeout --read-burst --backend-ipv4 --backend-ipv6 --backend --insecure --log-level --tls-proto-list --backend-http2-connections-per-worker --dh-param-file --worker-frontend-connections --header-field-buffer --no-server-push --no-location-rewrite --no-ocsp --backend-response-buffer --workers --frontend-http2-window-bits --no-host-rewrite --worker-write-rate --add-request-header --backend-tls-sni-field --subcert --help --frontend-frame-debug --pid-file --frontend-http2-dump-request-header --private-key-passwd-file --write-rate --altsvc --user --add-x-forwarded-for --syslog-facility --frontend-read-timeout --backlog --write-burst --backend-http2-window-bits --padding --stream-write-timeout --cacert --version --verify-client --backend-read-timeout --frontend --accesslog-file --http2-proxy --max-header-fields --backend-no-tls --client-private-key-file --client-cert-file --add-response-header --read-rate ' -- "$cur" ) )
             ;;
         *)
             _filedir

doc/h2load.1

@@ -1,6 +1,6 @@
 .\" Man page generated from reStructuredText.
 .
-.TH "H2LOAD" "1" "June 27, 2015" "1.0.5" "nghttp2"
+.TH "H2LOAD" "1" "July 15, 2015" "1.1.1" "nghttp2"
 .SH NAME
 h2load \- HTTP/2 benchmarking tool
 .
@@ -113,6 +113,12 @@ Add/Override a header to the requests.
 .UNINDENT
 .INDENT 0.0
 .TP
+.B \-\-ciphers=<SUITE>
+Set allowed  cipher list.  The  format of the  string is
+described in OpenSSL ciphers(1).
+.UNINDENT
+.INDENT 0.0
+.TP
 .B \-p, \-\-no\-tls\-proto=<PROTOID>
 Specify ALPN identifier of the  protocol to be used when
 accessing http URI without SSL/TLS.

doc/h2load.1.rst

@@ -84,6 +84,11 @@ OPTIONS
 
     Add/Override a header to the requests.
 
+.. option:: --ciphers=<SUITE>
+
+    Set allowed  cipher list.  The  format of the  string is
+    described in OpenSSL ciphers(1).
+
 .. option:: -p, --no-tls-proto=<PROTOID>
 
     Specify ALPN identifier of the  protocol to be used when

doc/nghttp.1

@@ -1,6 +1,6 @@
 .\" Man page generated from reStructuredText.
 .
-.TH "NGHTTP" "1" "June 27, 2015" "1.0.5" "nghttp2"
+.TH "NGHTTP" "1" "July 15, 2015" "1.1.1" "nghttp2"
 .SH NAME
 nghttp \- HTTP/2 experimental client
 .
@@ -205,6 +205,12 @@ Disable server push.
 .UNINDENT
 .INDENT 0.0
 .TP
+.B \-\-max\-concurrent\-streams=<N>
+The  number of  concurrent  pushed  streams this  client
+accepts.
+.UNINDENT
+.INDENT 0.0
+.TP
 .B \-\-version
 Display version information and exit.
 .UNINDENT

doc/nghttp.1.rst

@@ -158,6 +158,11 @@ OPTIONS
 
     Disable server push.
 
+.. option:: --max-concurrent-streams=<N>
+
+    The  number of  concurrent  pushed  streams this  client
+    accepts.
+
 .. option:: --version
 
     Display version information and exit.

doc/nghttpd.1

@@ -1,6 +1,6 @@
 .\" Man page generated from reStructuredText.
 .
-.TH "NGHTTPD" "1" "June 27, 2015" "1.0.5" "nghttp2"
+.TH "NGHTTPD" "1" "July 15, 2015" "1.1.1" "nghttp2"
 .SH NAME
 nghttpd \- HTTP/2 experimental server
 .

doc/nghttpx.1

@@ -1,6 +1,6 @@
 .\" Man page generated from reStructuredText.
 .
-.TH "NGHTTPX" "1" "June 27, 2015" "1.0.5" "nghttp2"
+.TH "NGHTTPX" "1" "July 15, 2015" "1.1.1" "nghttp2"
 .SH NAME
 nghttpx \- HTTP/2 experimental proxy
 .
@@ -55,17 +55,69 @@ The options are categorized into several groups.
 .SS Connections
 .INDENT 0.0
 .TP
-.B \-b, \-\-backend=<HOST,PORT>
+.B \-b, \-\-backend=(<HOST>,<PORT>|unix:<PATH>)[;<PATTERN>[:...]]
 Set  backend  host  and   port.   The  multiple  backend
 addresses are  accepted by repeating this  option.  UNIX
 domain socket  can be  specified by prefixing  path name
-with "unix:" (e.g., unix:/var/run/backend.sock)
+with "unix:" (e.g., unix:/var/run/backend.sock).
+.sp
+Optionally, if <PATTERN>s are given, the backend address
+is only used  if request matches the pattern.   If \fI\%\-s\fP or
+\fI\%\-p\fP  is  used,  <PATTERN>s   are  ignored.   The  pattern
+matching  is closely  designed to  ServeMux in  net/http
+package of Go  programming language.  <PATTERN> consists
+of path, host + path or  just host.  The path must start
+with "\fI/\fP".  If  it ends with "\fI/\fP", it  matches all request
+path in  its subtree.  To  deal with the request  to the
+directory without  trailing slash,  the path  which ends
+with "\fI/\fP" also matches the  request path which only lacks
+trailing \(aq\fI/\fP\(aq  (e.g., path  "\fI/foo/\fP" matches  request path
+"\fI/foo\fP").  If it does not end with "\fI/\fP", it performs exact
+match against  the request path.   If host is  given, it
+performs exact match against  the request host.  If host
+alone  is given,  "\fI/\fP"  is  appended to  it,  so that  it
+matches  all   request  paths  under  the   host  (e.g.,
+specifying "nghttp2.org" equals to "nghttp2.org/").
+.sp
+Patterns with  host take  precedence over  patterns with
+just path.   Then, longer patterns take  precedence over
+shorter  ones,  breaking  a  tie by  the  order  of  the
+appearance in the configuration.
+.sp
+If <PATTERN> is  omitted, "\fI/\fP" is used  as pattern, which
+matches  all  request  paths (catch\-all  pattern).   The
+catch\-all backend must be given.
+.sp
+When doing  a match, nghttpx made  some normalization to
+pattern, request host and path.  For host part, they are
+converted to lower case.  For path part, percent\-encoded
+unreserved characters  defined in RFC 3986  are decoded,
+and any  dot\-segments (".."  and ".")   are resolved and
+removed.
+.sp
+For   example,   \fI\%\-b\fP\(aq127.0.0.1,8080;nghttp2.org/httpbin/\(aq
+matches the  request host "nghttp2.org" and  the request
+path "\fI/httpbin/get\fP", but does not match the request host
+"nghttp2.org" and the request path "\fI/index.html\fP".
+.sp
+The  multiple <PATTERN>s  can  be specified,  delimiting
+them            by           ":".             Specifying
+\fI\%\-b\fP\(aq127.0.0.1,8080;nghttp2.org:www.nghttp2.org\(aq  has  the
+same  effect  to specify  \fI\%\-b\fP\(aq127.0.0.1,8080;nghttp2.org\(aq
+and \fI\%\-b\fP\(aq127.0.0.1,8080;www.nghttp2.org\(aq.
+.sp
+The backend addresses sharing same <PATTERN> are grouped
+together forming  load balancing  group.
+.sp
+Since ";" and ":" are  used as delimiter, <PATTERN> must
+not  contain these  characters.  Since  ";" has  special
+meaning in shell, the option value must be quoted.
 .sp
 Default: \fB127.0.0.1,80\fP
 .UNINDENT
 .INDENT 0.0
 .TP
-.B \-f, \-\-frontend=<HOST,PORT>
+.B \-f, \-\-frontend=(<HOST>,<PORT>|unix:<PATH>)
 Set  frontend  host and  port.   If  <HOST> is  \(aq*\(aq,  it
 assumes  all addresses  including  both  IPv4 and  IPv6.
 UNIX domain  socket can  be specified by  prefixing path
@@ -195,9 +247,14 @@ Default: \fB0\fP
 .INDENT 0.0
 .TP
 .B \-\-backend\-http2\-connections\-per\-worker=<N>
-Set  maximum number  of HTTP/2  connections per  worker.
+Set   maximum   number   of  backend   HTTP/2   physical
-The  default  value is  0,  which  means the  number  of
+connections  per  worker.   If  pattern is  used  in  \fI\%\-b\fP
-backend addresses specified by \fI\%\-b\fP option.
+option, this limit is applied  to each pattern group (in
+other  words, each  pattern group  can have  maximum <N>
+HTTP/2  connections).  The  default  value  is 0,  which
+means  that  the value  is  adjusted  to the  number  of
+backend addresses.  If pattern  is used, this adjustment
+is done for each pattern group.
 .UNINDENT
 .INDENT 0.0
 .TP
@@ -626,8 +683,20 @@ $pid: PID of the running process.
 $alpn: ALPN identifier of the protocol which generates
 the response.   For HTTP/1,  ALPN is  always http/1.1,
 regardless of minor version.
+.IP \(bu 2
+$ssl_cipher: cipher used for SSL/TLS connection.
+.IP \(bu 2
+$ssl_protocol: protocol for SSL/TLS connection.
+.IP \(bu 2
+$ssl_session_id: session ID for SSL/TLS connection.
+.IP \(bu 2
+$ssl_session_reused:  "r"   if  SSL/TLS   session  was
+reused.  Otherwise, "."
 .UNINDENT
 .sp
+The  variable  can  be  enclosed  by  "{"  and  "}"  for
+disambiguation (e.g., ${remote_addr}).
+.sp
 Default: \fB$remote_addr \- \- [$time_local] "$request" $status $body_bytes_sent "$http_referer" "$http_user_agent"\fP
 .UNINDENT
 .INDENT 0.0
@@ -786,6 +855,14 @@ Default: \fB/etc/nghttpx/nghttpx.conf\fP
 .UNINDENT
 .INDENT 0.0
 .TP
+.B \-\-include=<PATH>
+Load additional configurations from <PATH>.  File <PATH>
+is  read  when  configuration  parser  encountered  this
+option.  This option can be used multiple times, or even
+recursively.
+.UNINDENT
+.INDENT 0.0
+.TP
 .B \-v, \-\-version
 Print version and exit.
 .UNINDENT

doc/nghttpx.1.rst

@@ -37,16 +37,69 @@ The options are categorized into several groups.
 Connections
 ~~~~~~~~~~~
 
-.. option:: -b, --backend=<HOST,PORT>
+.. option:: -b, --backend=(<HOST>,<PORT>|unix:<PATH>)[;<PATTERN>[:...]]
 
     Set  backend  host  and   port.   The  multiple  backend
     addresses are  accepted by repeating this  option.  UNIX
     domain socket  can be  specified by prefixing  path name
-    with "unix:" (e.g., unix:/var/run/backend.sock)
+    with "unix:" (e.g., unix:/var/run/backend.sock).
+
+    Optionally, if <PATTERN>s are given, the backend address
+    is only used  if request matches the pattern.   If :option:`-s` or
+    :option:`-p`  is  used,  <PATTERN>s   are  ignored.   The  pattern
+    matching  is closely  designed to  ServeMux in  net/http
+    package of Go  programming language.  <PATTERN> consists
+    of path, host + path or  just host.  The path must start
+    with "*/*".  If  it ends with "*/*", it  matches all request
+    path in  its subtree.  To  deal with the request  to the
+    directory without  trailing slash,  the path  which ends
+    with "*/*" also matches the  request path which only lacks
+    trailing '*/*'  (e.g., path  "*/foo/*" matches  request path
+    "*/foo*").  If it does not end with "*/*", it performs exact
+    match against  the request path.   If host is  given, it
+    performs exact match against  the request host.  If host
+    alone  is given,  "*/*"  is  appended to  it,  so that  it
+    matches  all   request  paths  under  the   host  (e.g.,
+    specifying "nghttp2.org" equals to "nghttp2.org/").
+
+    Patterns with  host take  precedence over  patterns with
+    just path.   Then, longer patterns take  precedence over
+    shorter  ones,  breaking  a  tie by  the  order  of  the
+    appearance in the configuration.
+
+    If <PATTERN> is  omitted, "*/*" is used  as pattern, which
+    matches  all  request  paths (catch-all  pattern).   The
+    catch-all backend must be given.
+
+    When doing  a match, nghttpx made  some normalization to
+    pattern, request host and path.  For host part, they are
+    converted to lower case.  For path part, percent-encoded
+    unreserved characters  defined in RFC 3986  are decoded,
+    and any  dot-segments (".."  and ".")   are resolved and
+    removed.
+
+    For   example,   :option:`-b`\'127.0.0.1,8080;nghttp2.org/httpbin/'
+    matches the  request host "nghttp2.org" and  the request
+    path "*/httpbin/get*", but does not match the request host
+    "nghttp2.org" and the request path "*/index.html*".
+
+    The  multiple <PATTERN>s  can  be specified,  delimiting
+    them            by           ":".             Specifying
+    :option:`-b`\'127.0.0.1,8080;nghttp2.org:www.nghttp2.org'  has  the
+    same  effect  to specify  :option:`-b`\'127.0.0.1,8080;nghttp2.org'
+    and :option:`-b`\'127.0.0.1,8080;www.nghttp2.org'.
+
+    The backend addresses sharing same <PATTERN> are grouped
+    together forming  load balancing  group.
+
+    Since ";" and ":" are  used as delimiter, <PATTERN> must
+    not  contain these  characters.  Since  ";" has  special
+    meaning in shell, the option value must be quoted.
+
 
     Default: ``127.0.0.1,80``
 
-.. option:: -f, --frontend=<HOST,PORT>
+.. option:: -f, --frontend=(<HOST>,<PORT>|unix:<PATH>)
 
     Set  frontend  host and  port.   If  <HOST> is  '\*',  it
     assumes  all addresses  including  both  IPv4 and  IPv6.
@@ -165,9 +218,14 @@ Performance
 
 .. option:: --backend-http2-connections-per-worker=<N>
 
-    Set  maximum number  of HTTP/2  connections per  worker.
+    Set   maximum   number   of  backend   HTTP/2   physical
-    The  default  value is  0,  which  means the  number  of
+    connections  per  worker.   If  pattern is  used  in  :option:`-b`
-    backend addresses specified by :option:`-b` option.
+    option, this limit is applied  to each pattern group (in
+    other  words, each  pattern group  can have  maximum <N>
+    HTTP/2  connections).  The  default  value  is 0,  which
+    means  that  the value  is  adjusted  to the  number  of
+    backend addresses.  If pattern  is used, this adjustment
+    is done for each pattern group.
 
 .. option:: --backend-http1-connections-per-host=<N>
 
@@ -550,6 +608,14 @@ Logging
     * $alpn: ALPN identifier of the protocol which generates
       the response.   For HTTP/1,  ALPN is  always http/1.1,
       regardless of minor version.
+    * $ssl_cipher: cipher used for SSL/TLS connection.
+    * $ssl_protocol: protocol for SSL/TLS connection.
+    * $ssl_session_id: session ID for SSL/TLS connection.
+    * $ssl_session_reused:  "r"   if  SSL/TLS   session  was
+      reused.  Otherwise, "."
+
+    The  variable  can  be  enclosed  by  "{"  and  "}"  for
+    disambiguation (e.g., ${remote_addr}).
 
 
     Default: ``$remote_addr - - [$time_local] "$request" $status $body_bytes_sent "$http_referer" "$http_user_agent"``
@@ -700,6 +766,13 @@ Misc
 
     Default: ``/etc/nghttpx/nghttpx.conf``
 
+.. option:: --include=<PATH>
+
+    Load additional configurations from <PATH>.  File <PATH>
+    is  read  when  configuration  parser  encountered  this
+    option.  This option can be used multiple times, or even
+    recursively.
+
 .. option:: -v, --version
 
     Print version and exit.

gennghttpxfun.py

@@ -0,0 +1,117 @@
+#!/usr/bin/env python
+
+from gentokenlookup import gentokenlookup
+
+OPTIONS = [
+    "private-key-file",
+    "private-key-passwd-file",
+    "certificate-file",
+    "dh-param-file",
+    "subcert",
+    "backend",
+    "frontend",
+    "workers",
+    "http2-max-concurrent-streams",
+    "log-level",
+    "daemon",
+    "http2-proxy",
+    "http2-bridge",
+    "client-proxy",
+    "add-x-forwarded-for",
+    "strip-incoming-x-forwarded-for",
+    "no-via",
+    "frontend-http2-read-timeout",
+    "frontend-read-timeout",
+    "frontend-write-timeout",
+    "backend-read-timeout",
+    "backend-write-timeout",
+    "stream-read-timeout",
+    "stream-write-timeout",
+    "accesslog-file",
+    "accesslog-syslog",
+    "accesslog-format",
+    "errorlog-file",
+    "errorlog-syslog",
+    "backend-keep-alive-timeout",
+    "frontend-http2-window-bits",
+    "backend-http2-window-bits",
+    "frontend-http2-connection-window-bits",
+    "backend-http2-connection-window-bits",
+    "frontend-no-tls",
+    "backend-no-tls",
+    "backend-tls-sni-field",
+    "pid-file",
+    "user",
+    "syslog-facility",
+    "backlog",
+    "ciphers",
+    "client",
+    "insecure",
+    "cacert",
+    "backend-ipv4",
+    "backend-ipv6",
+    "backend-http-proxy-uri",
+    "read-rate",
+    "read-burst",
+    "write-rate",
+    "write-burst",
+    "worker-read-rate",
+    "worker-read-burst",
+    "worker-write-rate",
+    "worker-write-burst",
+    "npn-list",
+    "tls-proto-list",
+    "verify-client",
+    "verify-client-cacert",
+    "client-private-key-file",
+    "client-cert-file",
+    "frontend-http2-dump-request-header",
+    "frontend-http2-dump-response-header",
+    "http2-no-cookie-crumbling",
+    "frontend-frame-debug",
+    "padding",
+    "altsvc",
+    "add-request-header",
+    "add-response-header",
+    "worker-frontend-connections",
+    "no-location-rewrite",
+    "no-host-rewrite",
+    "backend-http1-connections-per-host",
+    "backend-http1-connections-per-frontend",
+    "listener-disable-timeout",
+    "tls-ticket-key-file",
+    "rlimit-nofile",
+    "backend-request-buffer",
+    "backend-response-buffer",
+    "no-server-push",
+    "backend-http2-connections-per-worker",
+    "fetch-ocsp-response-file",
+    "ocsp-update-interval",
+    "no-ocsp",
+    "header-field-buffer",
+    "max-header-fields",
+    "include",
+    "conf",
+]
+
+LOGVARS = [
+    "remote_addr",
+    "time_local",
+    "time_iso8601",
+    "request",
+    "status",
+    "body_bytes_sent",
+    "remote_port",
+    "server_port",
+    "request_time",
+    "pid",
+    "alpn",
+    "ssl_cipher",
+    "ssl_protocol",
+    "ssl_session_id",
+    "ssl_session_reused",
+]
+
+if __name__ == '__main__':
+    gentokenlookup(OPTIONS, 'SHRPX_OPTID', value_type='char', comp_fun='util::strieq_l')
+    gentokenlookup(LOGVARS, 'SHRPX_LOGF', value_type='char', comp_fun='util::strieq_l', return_type='LogFragmentType', fail_value='SHRPX_LOGF_NONE')

gentokenlookup.py

@@ -33,10 +33,10 @@ enum {'''
   {}_MAXIDX,
 }};'''.format(prefix)
 
-def gen_index_header(tokens, prefix):
+def gen_index_header(tokens, prefix, value_type, comp_fun, return_type, fail_value):
     print '''\
-int lookup_token(const uint8_t *name, size_t namelen) {
+{} lookup_token(const {} *name, size_t namelen) {{
-  switch (namelen) {'''
+  switch (namelen) {{'''.format(return_type, value_type)
     b = build_header(tokens)
     for size in sorted(b.keys()):
         ents = b[size]
@@ -50,20 +50,20 @@ int lookup_token(const uint8_t *name, size_t namelen) {
     case '{}':'''.format(c)
             for k in headers:
                 print '''\
-      if (util::streq_l("{}", name, {})) {{
+      if ({}("{}", name, {})) {{
         return {};
-      }}'''.format(k[:-1], size - 1, to_enum_hd(k, prefix))
+      }}'''.format(comp_fun, k[:-1], size - 1, to_enum_hd(k, prefix))
             print '''\
       break;'''
         print '''\
     }
     break;'''
     print '''\
-  }
+  }}
-  return -1;
+  return {};
-}'''
+}}'''.format(fail_value)
 
-def gentokenlookup(tokens, prefix):
+def gentokenlookup(tokens, prefix, value_type='uint8_t', comp_fun='util::streq_l', return_type='int', fail_value='-1'):
     gen_enum(tokens, prefix)
     print ''
-    gen_index_header(tokens, prefix)
+    gen_index_header(tokens, prefix, value_type, comp_fun, return_type, fail_value)

python/setup.py.in

@@ -22,7 +22,6 @@
 # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 from setuptools import setup, Extension
-from Cython.Build import cythonize
 
 LIBS = ['nghttp2']
 
@@ -34,13 +33,13 @@ setup(
     author_email = 'tatsuhiro.t@gmail.com',
     url = 'https://nghttp2.org/',
     keywords = [],
-    ext_modules = cythonize([Extension("nghttp2",
+    ext_modules = [Extension("nghttp2",
-                             ["nghttp2.pyx"],
+                             ["nghttp2.c"],
                              include_dirs=['@top_srcdir@/lib',
                                            '@top_srcdir@/lib/includes',
                                            '@top_builddir@/lib/includes'],
                              library_dirs=['@top_builddir@/lib/.libs',
                                            '@top_builddir@'],
-                             libraries=LIBS)]),
+                             libraries=LIBS)],
     long_description='TBD'
     )

src/Makefile.am

@@ -207,10 +207,10 @@ libnghttp2_asio_la_LDFLAGS = -no-undefined -version-info 1:0:0
 libnghttp2_asio_la_LIBADD = \
 	$(top_builddir)/lib/libnghttp2.la \
 	$(top_builddir)/third-party/libhttp-parser.la \
+	@OPENSSL_LIBS@ \
 	${BOOST_LDFLAGS} \
 	${BOOST_ASIO_LIB} \
 	${BOOST_THREAD_LIB} \
-	${BOOST_SYSTEM_LIB} \
+	${BOOST_SYSTEM_LIB}
-	@OPENSSL_LIBS@
 
 endif # ENABLE_ASIO_LIB

src/http2.h

@@ -37,6 +37,8 @@
 
 #include "http-parser/http_parser.h"
 
+#include "util.h"
+
 namespace nghttp2 {
 
 struct Header {
@@ -298,6 +300,55 @@ int lookup_method_token(const std::string &name);
 
 const char *to_method_string(int method_token);
 
+template <typename InputIt>
+std::string normalize_path(InputIt first, InputIt last) {
+  // First, decode %XX for unreserved characters, then do
+  // http2::join_path
+  std::string result;
+  // We won't find %XX if length is less than 3.
+  if (last - first < 3) {
+    result.assign(first, last);
+  } else {
+    for (; first < last - 2;) {
+      if (*first == '%') {
+        if (util::isHexDigit(*(first + 1)) && util::isHexDigit(*(first + 2))) {
+          auto c = (util::hex_to_uint(*(first + 1)) << 4) +
+                   util::hex_to_uint(*(first + 2));
+          if (util::inRFC3986UnreservedChars(c)) {
+            result += c;
+            first += 3;
+            continue;
+          }
+          result += '%';
+          result += util::upcase(*(first + 1));
+          result += util::upcase(*(first + 2));
+          first += 3;
+          continue;
+        }
+      }
+      result += *first++;
+    }
+    result.append(first, last);
+  }
+  return path_join(nullptr, 0, nullptr, 0, result.c_str(), result.size(),
+                   nullptr, 0);
+}
+
+template <typename InputIt>
+std::string rewrite_clean_path(InputIt first, InputIt last) {
+  if (first == last || *first != '/') {
+    return std::string(first, last);
+  }
+  // probably, not necessary most of the case, but just in case.
+  auto fragment = std::find(first, last, '#');
+  auto query = std::find(first, fragment, '?');
+  auto path = normalize_path(first, query);
+  if (query != fragment) {
+    path.append(query, fragment);
+  }
+  return path;
+}
+
 } // namespace http2
 
 } // namespace nghttp2

src/http2_test.cc

@@ -829,4 +829,56 @@ void test_http2_path_join(void) {
   }
 }
 
+void test_http2_normalize_path(void) {
+  std::string src;
+
+  src = "/alpha/bravo/../charlie";
+  CU_ASSERT("/alpha/charlie" ==
+            http2::normalize_path(std::begin(src), std::end(src)));
+
+  src = "/a%6c%70%68%61";
+  CU_ASSERT("/alpha" == http2::normalize_path(std::begin(src), std::end(src)));
+
+  src = "/alpha%2f%3a";
+  CU_ASSERT("/alpha%2F%3A" ==
+            http2::normalize_path(std::begin(src), std::end(src)));
+
+  src = "%2f";
+  CU_ASSERT("/%2F" == http2::normalize_path(std::begin(src), std::end(src)));
+
+  src = "%f";
+  CU_ASSERT("/%f" == http2::normalize_path(std::begin(src), std::end(src)));
+
+  src = "%";
+  CU_ASSERT("/%" == http2::normalize_path(std::begin(src), std::end(src)));
+
+  src = "";
+  CU_ASSERT("/" == http2::normalize_path(std::begin(src), std::end(src)));
+}
+
+void test_http2_rewrite_clean_path(void) {
+  std::string src;
+
+  // unreserved characters
+  src = "/alpha/%62ravo/";
+  CU_ASSERT("/alpha/bravo/" ==
+            http2::rewrite_clean_path(std::begin(src), std::end(src)));
+
+  // percent-encoding is converted to upper case.
+  src = "/delta%3a";
+  CU_ASSERT("/delta%3A" ==
+            http2::rewrite_clean_path(std::begin(src), std::end(src)));
+
+  // path component is normalized before mathcing
+  src = "/alpha/charlie/%2e././bravo/delta/..";
+  CU_ASSERT("/alpha/bravo/" ==
+            http2::rewrite_clean_path(std::begin(src), std::end(src)));
+
+  src = "alpha%3a";
+  CU_ASSERT(src == http2::rewrite_clean_path(std::begin(src), std::end(src)));
+
+  src = "";
+  CU_ASSERT(src == http2::rewrite_clean_path(std::begin(src), std::end(src)));
+}
+
 } // namespace shrpx

src/http2_test.h

@@ -45,6 +45,8 @@ void test_http2_http2_header_allowed(void);
 void test_http2_mandatory_request_headers_presence(void);
 void test_http2_parse_link_header(void);
 void test_http2_path_join(void);
+void test_http2_normalize_path(void);
+void test_http2_rewrite_clean_path(void);
 
 } // namespace shrpx
 

src/nghttp.cc

@@ -1379,7 +1379,8 @@ void HttpClient::output_har(FILE *outfile) {
 
     auto pushed = req->stream_id % 2 == 0;
 
-    json_object_set_new(entry, "comment", json_string(pushed ? "Pushed Object" : ""));
+    json_object_set_new(entry, "comment",
+                        json_string(pushed ? "Pushed Object" : ""));
 
     auto request = json_object();
     json_object_set_new(entry, "request", request);
@@ -1463,7 +1464,8 @@ void HttpClient::output_har(FILE *outfile) {
     json_object_set_new(timings, "receive", json_real(receive_delta));
 
     json_object_set_new(entry, "pageref", json_string(PAGE_ID));
-    json_object_set_new(entry, "connection", json_string(util::utos(req->stream_id).c_str()));
+    json_object_set_new(entry, "connection",
+                        json_string(util::utos(req->stream_id).c_str()));
   }
 
   json_dumpf(root, outfile, JSON_PRESERVE_ORDER | JSON_INDENT(2));

src/shrpx-unittest.cc

@@ -96,6 +96,10 @@ int main(int argc, char *argv[]) {
       !CU_add_test(pSuite, "http2_parse_link_header",
                    shrpx::test_http2_parse_link_header) ||
       !CU_add_test(pSuite, "http2_path_join", shrpx::test_http2_path_join) ||
+      !CU_add_test(pSuite, "http2_normalize_path",
+                   shrpx::test_http2_normalize_path) ||
+      !CU_add_test(pSuite, "http2_rewrite_clean_path",
+                   shrpx::test_http2_rewrite_clean_path) ||
       !CU_add_test(pSuite, "downstream_index_request_headers",
                    shrpx::test_downstream_index_request_headers) ||
       !CU_add_test(pSuite, "downstream_index_response_headers",
@@ -118,6 +122,8 @@ int main(int argc, char *argv[]) {
                    shrpx::test_shrpx_config_parse_log_format) ||
       !CU_add_test(pSuite, "config_read_tls_ticket_key_file",
                    shrpx::test_shrpx_config_read_tls_ticket_key_file) ||
+      !CU_add_test(pSuite, "config_match_downstream_addr_group",
+                   shrpx::test_shrpx_config_match_downstream_addr_group) ||
       !CU_add_test(pSuite, "util_streq", shrpx::test_util_streq) ||
       !CU_add_test(pSuite, "util_strieq", shrpx::test_util_strieq) ||
       !CU_add_test(pSuite, "util_inp_strlower",

src/shrpx.cc

@@ -966,6 +966,7 @@ void fill_default_config() {
   mod_config()->no_ocsp = false;
   mod_config()->header_field_buffer = 64_k;
   mod_config()->max_header_fields = 100;
+  mod_config()->downstream_addr_group_catch_all = 0;
 }
 } // namespace
 
@@ -997,14 +998,67 @@ Options:
   The options are categorized into several groups.
 
 Connections:
-  -b, --backend=<HOST,PORT>
+  -b, --backend=(<HOST>,<PORT>|unix:<PATH>)[;<PATTERN>[:...]]
               Set  backend  host  and   port.   The  multiple  backend
               addresses are  accepted by repeating this  option.  UNIX
               domain socket  can be  specified by prefixing  path name
-              with "unix:" (e.g., unix:/var/run/backend.sock)
+              with "unix:" (e.g., unix:/var/run/backend.sock).
+
+              Optionally, if <PATTERN>s are given, the backend address
+              is only used  if request matches the pattern.   If -s or
+              -p  is  used,  <PATTERN>s   are  ignored.   The  pattern
+              matching  is closely  designed to  ServeMux in  net/http
+              package of Go  programming language.  <PATTERN> consists
+              of path, host + path or  just host.  The path must start
+              with "/".  If  it ends with "/", it  matches all request
+              path in  its subtree.  To  deal with the request  to the
+              directory without  trailing slash,  the path  which ends
+              with "/" also matches the  request path which only lacks
+              trailing '/'  (e.g., path  "/foo/" matches  request path
+              "/foo").  If it does not end with "/", it performs exact
+              match against  the request path.   If host is  given, it
+              performs exact match against  the request host.  If host
+              alone  is given,  "/"  is  appended to  it,  so that  it
+              matches  all   request  paths  under  the   host  (e.g.,
+              specifying "nghttp2.org" equals to "nghttp2.org/").
+
+              Patterns with  host take  precedence over  patterns with
+              just path.   Then, longer patterns take  precedence over
+              shorter  ones,  breaking  a  tie by  the  order  of  the
+              appearance in the configuration.
+
+              If <PATTERN> is  omitted, "/" is used  as pattern, which
+              matches  all  request  paths (catch-all  pattern).   The
+              catch-all backend must be given.
+
+              When doing  a match, nghttpx made  some normalization to
+              pattern, request host and path.  For host part, they are
+              converted to lower case.  For path part, percent-encoded
+              unreserved characters  defined in RFC 3986  are decoded,
+              and any  dot-segments (".."  and ".")   are resolved and
+              removed.
+
+              For   example,   -b'127.0.0.1,8080;nghttp2.org/httpbin/'
+              matches the  request host "nghttp2.org" and  the request
+              path "/httpbin/get", but does not match the request host
+              "nghttp2.org" and the request path "/index.html".
+
+              The  multiple <PATTERN>s  can  be specified,  delimiting
+              them            by           ":".             Specifying
+              -b'127.0.0.1,8080;nghttp2.org:www.nghttp2.org'  has  the
+              same  effect  to specify  -b'127.0.0.1,8080;nghttp2.org'
+              and -b'127.0.0.1,8080;www.nghttp2.org'.
+
+              The backend addresses sharing same <PATTERN> are grouped
+              together forming  load balancing  group.
+
+              Since ";" and ":" are  used as delimiter, <PATTERN> must
+              not  contain these  characters.  Since  ";" has  special
+              meaning in shell, the option value must be quoted.
+
               Default: )" << DEFAULT_DOWNSTREAM_HOST << ","
       << DEFAULT_DOWNSTREAM_PORT << R"(
-  -f, --frontend=<HOST,PORT>
+  -f, --frontend=(<HOST>,<PORT>|unix:<PATH>)
               Set  frontend  host and  port.   If  <HOST> is  '*',  it
               assumes  all addresses  including  both  IPv4 and  IPv6.
               UNIX domain  socket can  be specified by  prefixing path
@@ -1079,9 +1133,14 @@ Performance:
               accepts.  Setting 0 means unlimited.
               Default: )" << get_config()->worker_frontend_connections << R"(
   --backend-http2-connections-per-worker=<N>
-              Set  maximum number  of HTTP/2  connections per  worker.
+              Set   maximum   number   of  backend   HTTP/2   physical
-              The  default  value is  0,  which  means the  number  of
+              connections  per  worker.   If  pattern is  used  in  -b
-              backend addresses specified by -b option.
+              option, this limit is applied  to each pattern group (in
+              other  words, each  pattern group  can have  maximum <N>
+              HTTP/2  connections).  The  default  value  is 0,  which
+              means  that  the value  is  adjusted  to the  number  of
+              backend addresses.  If pattern  is used, this adjustment
+              is done for each pattern group.
   --backend-http1-connections-per-host=<N>
               Set   maximum  number   of  backend   concurrent  HTTP/1
               connections per origin host.   This option is meaningful
@@ -1351,6 +1410,9 @@ Logging:
               * $ssl_session_reused:  "r"   if  SSL/TLS   session  was
                 reused.  Otherwise, "."
 
+              The  variable  can  be  enclosed  by  "{"  and  "}"  for
+              disambiguation (e.g., ${remote_addr}).
+
               Default: )" << DEFAULT_ACCESSLOG_FORMAT << R"(
   --errorlog-file=<PATH>
               Set path to write error  log.  To reopen file, send USR1
@@ -1446,6 +1508,11 @@ Misc:
   --conf=<PATH>
               Load configuration from <PATH>.
               Default: )" << get_config()->conf_path.get() << R"(
+  --include=<PATH>
+              Load additional configurations from <PATH>.  File <PATH>
+              is  read  when  configuration  parser  encountered  this
+              option.  This option can be used multiple times, or even
+              recursively.
   -v, --version
               Print version and exit.
   -h, --help  Print this help and exit.
@@ -1592,6 +1659,7 @@ int main(int argc, char **argv) {
         {SHRPX_OPT_HEADER_FIELD_BUFFER, required_argument, &flag, 80},
         {SHRPX_OPT_MAX_HEADER_FIELDS, required_argument, &flag, 81},
         {SHRPX_OPT_ADD_REQUEST_HEADER, required_argument, &flag, 82},
+        {SHRPX_OPT_INCLUDE, required_argument, &flag, 83},
         {nullptr, 0, nullptr, 0}};
 
     int option_index = 0;
@@ -1954,6 +2022,10 @@ int main(int argc, char **argv) {
         // --add-request-header
         cmdcfgs.emplace_back(SHRPX_OPT_ADD_REQUEST_HEADER, optarg);
         break;
+      case 83:
+        // --include
+        cmdcfgs.emplace_back(SHRPX_OPT_INCLUDE, optarg);
+        break;
       default:
         break;
       }
@@ -1964,11 +2036,13 @@ int main(int argc, char **argv) {
   }
 
   if (conf_exists(get_config()->conf_path.get())) {
-    if (load_config(get_config()->conf_path.get()) == -1) {
+    std::set<std::string> include_set;
+    if (load_config(get_config()->conf_path.get(), include_set) == -1) {
       LOG(FATAL) << "Failed to load configuration from "
                  << get_config()->conf_path.get();
       exit(EXIT_FAILURE);
     }
+    assert(include_set.empty());
   }
 
   if (argc - optind >= 2) {
@@ -1980,13 +2054,20 @@ int main(int argc, char **argv) {
   // parsing option values.
   reopen_log_files();
 
+  {
+    std::set<std::string> include_set;
+
     for (size_t i = 0, len = cmdcfgs.size(); i < len; ++i) {
-    if (parse_config(cmdcfgs[i].first, cmdcfgs[i].second) == -1) {
+      if (parse_config(cmdcfgs[i].first, cmdcfgs[i].second, include_set) ==
+          -1) {
         LOG(FATAL) << "Failed to parse command-line argument.";
         exit(EXIT_FAILURE);
       }
     }
 
+    assert(include_set.empty());
+  }
+
   if (get_config()->accesslog_syslog || get_config()->errorlog_syslog) {
     openlog("nghttpx", LOG_NDELAY | LOG_NOWAIT | LOG_PID,
             get_config()->syslog_facility);
@@ -2118,19 +2199,59 @@ int main(int argc, char **argv) {
     }
   }
 
-  if (get_config()->downstream_addrs.empty()) {
+  if (get_config()->downstream_addr_groups.empty()) {
     DownstreamAddr addr;
     addr.host = strcopy(DEFAULT_DOWNSTREAM_HOST);
     addr.port = DEFAULT_DOWNSTREAM_PORT;
 
-    mod_config()->downstream_addrs.push_back(std::move(addr));
+    DownstreamAddrGroup g("/");
+    g.addrs.push_back(std::move(addr));
+    mod_config()->downstream_addr_groups.push_back(std::move(g));
+  } else if (get_config()->http2_proxy || get_config()->client_proxy) {
+    // We don't support host mapping in these cases.  Move all
+    // non-catch-all patterns to catch-all pattern.
+    DownstreamAddrGroup catch_all("/");
+    for (auto &g : mod_config()->downstream_addr_groups) {
+      std::move(std::begin(g.addrs), std::end(g.addrs),
+                std::back_inserter(catch_all.addrs));
+    }
+    std::vector<DownstreamAddrGroup>().swap(
+        mod_config()->downstream_addr_groups);
+    mod_config()->downstream_addr_groups.push_back(std::move(catch_all));
   }
 
   if (LOG_ENABLED(INFO)) {
     LOG(INFO) << "Resolving backend address";
   }
 
-  for (auto &addr : mod_config()->downstream_addrs) {
+  ssize_t catch_all_group = -1;
+  for (size_t i = 0; i < mod_config()->downstream_addr_groups.size(); ++i) {
+    auto &g = mod_config()->downstream_addr_groups[i];
+    if (g.pattern == "/") {
+      catch_all_group = i;
+    }
+    if (LOG_ENABLED(INFO)) {
+      LOG(INFO) << "Host-path pattern: group " << i << ": '" << g.pattern
+                << "'";
+      for (auto &addr : g.addrs) {
+        LOG(INFO) << "group " << i << " -> " << addr.host.get()
+                  << (addr.host_unix ? "" : ":" + util::utos(addr.port));
+      }
+    }
+  }
+
+  if (catch_all_group == -1) {
+    LOG(FATAL) << "-b: No catch-all backend address is configured";
+    exit(EXIT_FAILURE);
+  }
+  mod_config()->downstream_addr_group_catch_all = catch_all_group;
+
+  if (LOG_ENABLED(INFO)) {
+    LOG(INFO) << "Catch-all pattern is group " << catch_all_group;
+  }
+
+  for (auto &g : mod_config()->downstream_addr_groups) {
+    for (auto &addr : g.addrs) {
 
       if (addr.host_unix) {
         // for AF_UNIX socket, we use "localhost" as host for backend
@@ -2163,12 +2284,13 @@ int main(int argc, char **argv) {
 
       if (resolve_hostname(
               &addr.addr, &addr.addrlen, addr.host.get(), addr.port,
-            get_config()->backend_ipv4
+              get_config()->backend_ipv4 ? AF_INET : (get_config()->backend_ipv6
-                ? AF_INET
+                                                          ? AF_INET6
-                : (get_config()->backend_ipv6 ? AF_INET6 : AF_UNSPEC)) == -1) {
+                                                          : AF_UNSPEC)) == -1) {
         exit(EXIT_FAILURE);
       }
     }
+  }
 
   if (get_config()->downstream_http_proxy_host) {
     if (LOG_ENABLED(INFO)) {
@@ -2183,11 +2305,6 @@ int main(int argc, char **argv) {
     }
   }
 
-  if (get_config()->http2_downstream_connections_per_worker == 0) {
-    mod_config()->http2_downstream_connections_per_worker =
-        get_config()->downstream_addrs.size();
-  }
-
   if (get_config()->rlimit_nofile) {
     struct rlimit lim = {static_cast<rlim_t>(get_config()->rlimit_nofile),
                          static_cast<rlim_t>(get_config()->rlimit_nofile)};

src/shrpx_client_handler.cc

@@ -39,6 +39,7 @@
 #include "shrpx_worker.h"
 #include "shrpx_downstream_connection_pool.h"
 #include "shrpx_downstream.h"
+#include "shrpx_http2_session.h"
 #ifdef HAVE_SPDYLAY
 #include "shrpx_spdy_upstream.h"
 #endif // HAVE_SPDYLAY
@@ -360,8 +361,12 @@ ClientHandler::ClientHandler(Worker *worker, int fd, SSL *ssl,
             get_config()->upstream_read_timeout, get_config()->write_rate,
             get_config()->write_burst, get_config()->read_rate,
             get_config()->read_burst, writecb, readcb, timeoutcb, this),
+      pinned_http2sessions_(
+          get_config()->downstream_proto == PROTO_HTTP2
+              ? make_unique<std::vector<ssize_t>>(
+                    get_config()->downstream_addr_groups.size(), -1)
+              : nullptr),
       ipaddr_(ipaddr), port_(port), worker_(worker),
-      http2session_(worker_->next_http2_session()),
       left_connhd_len_(NGHTTP2_CLIENT_MAGIC_LEN),
       should_close_after_write_(false) {
 
@@ -588,7 +593,8 @@ void ClientHandler::pool_downstream_connection(
     return;
   }
   if (LOG_ENABLED(INFO)) {
-    CLOG(INFO, this) << "Pooling downstream connection DCONN:" << dconn.get();
+    CLOG(INFO, this) << "Pooling downstream connection DCONN:" << dconn.get()
+                     << " in group " << dconn->get_group();
   }
   dconn->set_client_handler(nullptr);
   auto dconn_pool = worker_->get_dconn_pool();
@@ -605,9 +611,43 @@ void ClientHandler::remove_downstream_connection(DownstreamConnection *dconn) {
 }
 
 std::unique_ptr<DownstreamConnection>
-ClientHandler::get_downstream_connection() {
+ClientHandler::get_downstream_connection(Downstream *downstream) {
+  size_t group;
+  auto &groups = get_config()->downstream_addr_groups;
+  auto catch_all = get_config()->downstream_addr_group_catch_all;
+
+  // Fast path.  If we have one group, it must be catch-all group.
+  // HTTP/2 and client proxy modes fall in this case.
+  if (groups.size() == 1) {
+    group = 0;
+  } else if (downstream->get_request_method() == HTTP_CONNECT) {
+    //  We don't know how to treat CONNECT request in host-path
+    //  mapping.  It most likely appears in proxy scenario.  Since we
+    //  have dealt with proxy case already, just use catch-all group.
+    group = catch_all;
+  } else {
+    if (!downstream->get_request_http2_authority().empty()) {
+      group = match_downstream_addr_group(
+          downstream->get_request_http2_authority(),
+          downstream->get_request_path(), groups, catch_all);
+    } else {
+      auto h = downstream->get_request_header(http2::HD_HOST);
+      if (h) {
+        group = match_downstream_addr_group(
+            h->value, downstream->get_request_path(), groups, catch_all);
+      } else {
+        group = match_downstream_addr_group("", downstream->get_request_path(),
+                                            groups, catch_all);
+      }
+    }
+  }
+
+  if (LOG_ENABLED(INFO)) {
+    CLOG(INFO, this) << "Downstream address group: " << group;
+  }
+
   auto dconn_pool = worker_->get_dconn_pool();
-  auto dconn = dconn_pool->pop_downstream_connection();
+  auto dconn = dconn_pool->pop_downstream_connection(group);
 
   if (!dconn) {
     if (LOG_ENABLED(INFO)) {
@@ -617,10 +657,20 @@ ClientHandler::get_downstream_connection() {
 
     auto dconn_pool = worker_->get_dconn_pool();
 
-    if (http2session_) {
+    if (get_config()->downstream_proto == PROTO_HTTP2) {
-      dconn = make_unique<Http2DownstreamConnection>(dconn_pool, http2session_);
+      Http2Session *http2session;
+      auto &pinned = (*pinned_http2sessions_)[group];
+      if (pinned == -1) {
+        http2session = worker_->next_http2_session(group);
+        pinned = http2session->get_index();
       } else {
-      dconn = make_unique<HttpDownstreamConnection>(dconn_pool, conn_.loop);
+        auto dgrp = worker_->get_dgrp(group);
+        http2session = dgrp->http2sessions[pinned].get();
+      }
+      dconn = make_unique<Http2DownstreamConnection>(dconn_pool, http2session);
+    } else {
+      dconn =
+          make_unique<HttpDownstreamConnection>(dconn_pool, group, conn_.loop);
     }
     dconn->set_client_handler(this);
     return dconn;

src/shrpx_client_handler.h

@@ -44,7 +44,6 @@ namespace shrpx {
 
 class Upstream;
 class DownstreamConnection;
-class Http2Session;
 class HttpsUpstream;
 class ConnectBlocker;
 class DownstreamConnectionPool;
@@ -92,7 +91,8 @@ public:
 
   void pool_downstream_connection(std::unique_ptr<DownstreamConnection> dconn);
   void remove_downstream_connection(DownstreamConnection *dconn);
-  std::unique_ptr<DownstreamConnection> get_downstream_connection();
+  std::unique_ptr<DownstreamConnection>
+  get_downstream_connection(Downstream *downstream);
   MemchunkPool *get_mcpool();
   SSL *get_ssl() const;
   ConnectBlocker *get_connect_blocker() const;
@@ -134,6 +134,7 @@ private:
   Connection conn_;
   ev_timer reneg_shutdown_timer_;
   std::unique_ptr<Upstream> upstream_;
+  std::unique_ptr<std::vector<ssize_t>> pinned_http2sessions_;
   std::string ipaddr_;
   std::string port_;
   // The ALPN identifier negotiated for this connection.
@@ -141,7 +142,6 @@ private:
   std::function<int(ClientHandler &)> read_, write_;
   std::function<int(ClientHandler &)> on_read_, on_write_;
   Worker *worker_;
-  Http2Session *http2session_;
   // The number of bytes of HTTP/2 client connection header to read
   size_t left_connhd_len_;
   bool should_close_after_write_;

src/shrpx_config.h

@@ -42,6 +42,7 @@
 #include <cstdio>
 #include <vector>
 #include <memory>
+#include <set>
 
 #include <openssl/ssl.h>
 
@@ -49,6 +50,10 @@
 
 #include <nghttp2/nghttp2.h>
 
+#include "template.h"
+
+using namespace nghttp2;
+
 namespace shrpx {
 
 struct LogFragment;
@@ -165,6 +170,7 @@ constexpr char SHRPX_OPT_OCSP_UPDATE_INTERVAL[] = "ocsp-update-interval";
 constexpr char SHRPX_OPT_NO_OCSP[] = "no-ocsp";
 constexpr char SHRPX_OPT_HEADER_FIELD_BUFFER[] = "header-field-buffer";
 constexpr char SHRPX_OPT_MAX_HEADER_FIELDS[] = "max-header-fields";
+constexpr char SHRPX_OPT_INCLUDE[] = "include";
 
 union sockaddr_union {
   sockaddr_storage storage;
@@ -194,6 +200,11 @@ struct AltSvc {
 
 struct DownstreamAddr {
   DownstreamAddr() : addr{{0}}, addrlen(0), port(0), host_unix(false) {}
+  DownstreamAddr(const DownstreamAddr &other);
+  DownstreamAddr(DownstreamAddr &&) = default;
+  DownstreamAddr &operator=(const DownstreamAddr &other);
+  DownstreamAddr &operator=(DownstreamAddr &&other) = default;
+
   sockaddr_union addr;
   // backend address.  If |host_unix| is true, this is UNIX domain
   // socket path.
@@ -206,6 +217,12 @@ struct DownstreamAddr {
   bool host_unix;
 };
 
+struct DownstreamAddrGroup {
+  DownstreamAddrGroup(std::string pattern) : pattern(std::move(pattern)) {}
+  std::string pattern;
+  std::vector<DownstreamAddr> addrs;
+};
+
 struct TicketKey {
   uint8_t name[16];
   uint8_t aes_key[16];
@@ -225,7 +242,7 @@ struct Config {
   std::vector<std::pair<std::string, std::string>> add_response_headers;
   std::vector<unsigned char> alpn_prefs;
   std::vector<LogFragment> accesslog_format;
-  std::vector<DownstreamAddr> downstream_addrs;
+  std::vector<DownstreamAddrGroup> downstream_addr_groups;
   std::vector<std::string> tls_ticket_key_files;
   // binary form of http proxy host and port
   sockaddr_union downstream_http_proxy_addr;
@@ -311,6 +328,8 @@ struct Config {
   size_t downstream_response_buffer_size;
   size_t header_field_buffer;
   size_t max_header_fields;
+  // The index of catch-all group in downstream_addr_groups.
+  size_t downstream_addr_group_catch_all;
   // Bit mask to disable SSL/TLS protocol versions.  This will be
   // passed to SSL_CTX_set_options().
   long int tls_proto_mask;
@@ -365,26 +384,28 @@ void create_config();
 
 // Parses option name |opt| and value |optarg|.  The results are
 // stored into statically allocated Config object. This function
-// returns 0 if it succeeds, or -1.
+// returns 0 if it succeeds, or -1.  The |included_set| contains the
-int parse_config(const char *opt, const char *optarg);
+// all paths already included while processing this configuration, to
+// avoid loop in --include option.
+int parse_config(const char *opt, const char *optarg,
+                 std::set<std::string> &included_set);
 
 // Loads configurations from |filename| and stores them in statically
 // allocated Config object. This function returns 0 if it succeeds, or
-// -1.
+// -1.  See parse_config() for |include_set|.
-int load_config(const char *filename);
+int load_config(const char *filename, std::set<std::string> &include_set);
 
 // Read passwd from |filename|
 std::string read_passwd_from_file(const char *filename);
 
-// Parses comma delimited strings in |s| and returns the array of
+// Parses delimited strings in |s| and returns the array of pointers,
-// pointers, each element points to the each substring in |s|.  The
+// each element points to the each substring in |s|.  The delimiter is
-// |s| must be comma delimited list of strings.  The strings must be
+// given by |delim.  The |s| must be comma delimited list of strings.
-// delimited by a single comma and any white spaces around it are
+// The strings must be delimited by a single comma and any white
-// treated as a part of protocol strings.  This function may modify
+// spaces around it are treated as a part of protocol strings.  This
-// |s| and the caller must leave it as is after this call.  This
 // function copies |s| and first element in the return value points to
 // it.  It is caller's responsibility to deallocate its memory.
-std::vector<char *> parse_config_str_list(const char *s);
+std::vector<char *> parse_config_str_list(const char *s, char delim = ',');
 
 // Clears all elements of |list|, which is returned by
 // parse_config_str_list().  If list is not empty, list[0] is freed by
@@ -399,15 +420,23 @@ std::pair<std::string, std::string> parse_header(const char *optarg);
 
 std::vector<LogFragment> parse_log_format(const char *optarg);
 
-// Returns a copy of NULL-terminated string |val|.
+// Returns a copy of NULL-terminated string [first, last).
-std::unique_ptr<char[]> strcopy(const char *val);
+template <typename InputIt>
+std::unique_ptr<char[]> strcopy(InputIt first, InputIt last) {
+  auto res = make_unique<char[]>(last - first + 1);
+  *std::copy(first, last, res.get()) = '\0';
+  return res;
+}
 
-// Returns a copy of string |val| of length |n|.  The returned string
+// Returns a copy of NULL-terminated string |val|.
-// will be NULL-terminated.
+inline std::unique_ptr<char[]> strcopy(const char *val) {
-std::unique_ptr<char[]> strcopy(const char *val, size_t n);
+  return strcopy(val, val + strlen(val));
+}
 
 // Returns a copy of val.c_str().
-std::unique_ptr<char[]> strcopy(const std::string &val);
+inline std::unique_ptr<char[]> strcopy(const std::string &val) {
+  return strcopy(std::begin(val), std::end(val));
+}
 
 // Returns string for syslog |facility|.
 const char *str_syslog_facility(int facility);
@@ -423,6 +452,16 @@ FILE *open_file_for_write(const char *filename);
 std::unique_ptr<TicketKeys>
 read_tls_ticket_key_file(const std::vector<std::string> &files);
 
+// Selects group based on request's |hostport| and |path|.  |hostport|
+// is the value taken from :authority or host header field, and may
+// contain port.  The |path| may contain query part.  We require the
+// catch-all pattern in place, so this function always selects one
+// group.  The catch-all group index is given in |catch_all|.  All
+// patterns are given in |groups|.
+size_t match_downstream_addr_group(
+    const std::string &hostport, const std::string &path,
+    const std::vector<DownstreamAddrGroup> &groups, size_t catch_all);
+
 } // namespace shrpx
 
 #endif // SHRPX_CONFIG_H

src/shrpx_config_test.cc

@@ -48,7 +48,7 @@ void test_shrpx_config_parse_config_str_list(void) {
   CU_ASSERT(0 == strcmp("", res[1]));
   clear_config_str_list(res);
 
-  res = parse_config_str_list(",a,,");
+  res = parse_config_str_list(":a::", ':');
   CU_ASSERT(4 == res.size());
   CU_ASSERT(0 == strcmp("", res[0]));
   CU_ASSERT(0 == strcmp("a", res[1]));
@@ -95,9 +95,9 @@ void test_shrpx_config_parse_header(void) {
 }
 
 void test_shrpx_config_parse_log_format(void) {
-  auto res = parse_log_format("$remote_addr - $remote_user [$time_local] "
+  auto res = parse_log_format(R"($remote_addr - $remote_user [$time_local] )"
-                              "\"$request\" $status $body_bytes_sent "
+                              R"("$request" $status $body_bytes_sent )"
-                              "\"$http_referer\" \"$http_user_agent\"");
+                              R"("${http_referer}" "$http_user_agent")");
   CU_ASSERT(14 == res.size());
 
   CU_ASSERT(SHRPX_LOGF_REMOTE_ADDR == res[0].type);
@@ -136,6 +136,44 @@ void test_shrpx_config_parse_log_format(void) {
 
   CU_ASSERT(SHRPX_LOGF_LITERAL == res[13].type);
   CU_ASSERT(0 == strcmp("\"", res[13].value.get()));
+
+  res = parse_log_format("$");
+
+  CU_ASSERT(1 == res.size());
+
+  CU_ASSERT(SHRPX_LOGF_LITERAL == res[0].type);
+  CU_ASSERT(0 == strcmp("$", res[0].value.get()));
+
+  res = parse_log_format("${");
+
+  CU_ASSERT(1 == res.size());
+
+  CU_ASSERT(SHRPX_LOGF_LITERAL == res[0].type);
+  CU_ASSERT(0 == strcmp("${", res[0].value.get()));
+
+  res = parse_log_format("${a");
+
+  CU_ASSERT(1 == res.size());
+
+  CU_ASSERT(SHRPX_LOGF_LITERAL == res[0].type);
+  CU_ASSERT(0 == strcmp("${a", res[0].value.get()));
+
+  res = parse_log_format("${a ");
+
+  CU_ASSERT(1 == res.size());
+
+  CU_ASSERT(SHRPX_LOGF_LITERAL == res[0].type);
+  CU_ASSERT(0 == strcmp("${a ", res[0].value.get()));
+
+  res = parse_log_format("$$remote_addr");
+
+  CU_ASSERT(2 == res.size());
+
+  CU_ASSERT(SHRPX_LOGF_LITERAL == res[0].type);
+  CU_ASSERT(0 == strcmp("$", res[0].value.get()));
+
+  CU_ASSERT(SHRPX_LOGF_REMOTE_ADDR == res[1].type);
+  CU_ASSERT(nullptr == res[1].value.get());
 }
 
 void test_shrpx_config_read_tls_ticket_key_file(void) {
@@ -172,4 +210,64 @@ void test_shrpx_config_read_tls_ticket_key_file(void) {
             memcmp("a..............b", key->hmac_key, sizeof(key->hmac_key)));
 }
 
+void test_shrpx_config_match_downstream_addr_group(void) {
+  auto groups = std::vector<DownstreamAddrGroup>{
+      {"nghttp2.org/"},
+      {"nghttp2.org/alpha/bravo/"},
+      {"nghttp2.org/alpha/charlie"},
+      {"nghttp2.org/delta%3A"},
+      {"www.nghttp2.org/"},
+      {"[::1]/"},
+  };
+
+  CU_ASSERT(0 == match_downstream_addr_group("nghttp2.org", "/", groups, 255));
+
+  // port is removed
+  CU_ASSERT(0 ==
+            match_downstream_addr_group("nghttp2.org:8080", "/", groups, 255));
+
+  // host is case-insensitive
+  CU_ASSERT(4 == match_downstream_addr_group("WWW.nghttp2.org", "/alpha",
+                                             groups, 255));
+
+  CU_ASSERT(1 == match_downstream_addr_group("nghttp2.org", "/alpha/bravo/",
+                                             groups, 255));
+
+  // /alpha/bravo also matches /alpha/bravo/
+  CU_ASSERT(1 == match_downstream_addr_group("nghttp2.org", "/alpha/bravo",
+                                             groups, 255));
+
+  // path part is case-sensitive
+  CU_ASSERT(0 == match_downstream_addr_group("nghttp2.org", "/Alpha/bravo",
+                                             groups, 255));
+
+  CU_ASSERT(1 == match_downstream_addr_group(
+                     "nghttp2.org", "/alpha/bravo/charlie", groups, 255));
+
+  CU_ASSERT(2 == match_downstream_addr_group("nghttp2.org", "/alpha/charlie",
+                                             groups, 255));
+
+  // pattern which does not end with '/' must match its entirely.  So
+  // this matches to group 0, not group 2.
+  CU_ASSERT(0 == match_downstream_addr_group("nghttp2.org", "/alpha/charlie/",
+                                             groups, 255));
+
+  CU_ASSERT(255 ==
+            match_downstream_addr_group("example.org", "/", groups, 255));
+
+  CU_ASSERT(255 == match_downstream_addr_group("", "/", groups, 255));
+
+  CU_ASSERT(255 == match_downstream_addr_group("", "alpha", groups, 255));
+
+  CU_ASSERT(255 == match_downstream_addr_group("foo/bar", "/", groups, 255));
+
+  // If path is "*", only match with host + "/".
+  CU_ASSERT(0 == match_downstream_addr_group("nghttp2.org", "*", groups, 255));
+
+  CU_ASSERT(5 == match_downstream_addr_group("[::1]", "/", groups, 255));
+  CU_ASSERT(5 == match_downstream_addr_group("[::1]:8080", "/", groups, 255));
+  CU_ASSERT(255 == match_downstream_addr_group("[::1", "/", groups, 255));
+  CU_ASSERT(255 == match_downstream_addr_group("[::1]8000", "/", groups, 255));
+}
+
 } // namespace shrpx

src/shrpx_config_test.h

@@ -35,6 +35,7 @@ void test_shrpx_config_parse_config_str_list(void);
 void test_shrpx_config_parse_header(void);
 void test_shrpx_config_parse_log_format(void);
 void test_shrpx_config_read_tls_ticket_key_file(void);
+void test_shrpx_config_match_downstream_addr_group(void);
 
 } // namespace shrpx
 

src/shrpx_downstream.cc

@@ -152,10 +152,6 @@ Downstream::~Downstream() {
     DLOG(INFO, this) << "Deleting";
   }
 
-  if (blocked_link_) {
-    detach_blocked_link(blocked_link_);
-  }
-
   // check nullptr for unittest
   if (upstream_) {
     auto loop = upstream_->get_client_handler()->get_loop();
@@ -166,6 +162,10 @@ Downstream::~Downstream() {
     ev_timer_stop(loop, &downstream_wtimer_);
   }
 
+  // DownstreamConnection may refer to this object.  Delete it now
+  // explicitly.
+  dconn_.reset();
+
   if (LOG_ENABLED(INFO)) {
     DLOG(INFO, this) << "Deleted";
   }
@@ -195,8 +195,6 @@ void Downstream::detach_downstream_connection() {
       std::unique_ptr<DownstreamConnection>(dconn_.release()));
 }
 
-void Downstream::release_downstream_connection() { dconn_.release(); }
-
 DownstreamConnection *Downstream::get_downstream_connection() {
   return dconn_.get();
 }
@@ -1200,12 +1198,10 @@ void Downstream::attach_blocked_link(BlockedLink *l) {
   blocked_link_ = l;
 }
 
-void Downstream::detach_blocked_link(BlockedLink *l) {
+BlockedLink *Downstream::detach_blocked_link() {
-  assert(blocked_link_);
+  auto link = blocked_link_;
-  assert(l->downstream == this);
-
-  l->downstream = nullptr;
   blocked_link_ = nullptr;
+  return link;
 }
 
 void Downstream::add_request_headers_sum(size_t amount) {

src/shrpx_downstream.h

@@ -69,8 +69,6 @@ public:
 
   int attach_downstream_connection(std::unique_ptr<DownstreamConnection> dconn);
   void detach_downstream_connection();
-  // Releases dconn_, without freeing it.
-  void release_downstream_connection();
   DownstreamConnection *get_downstream_connection();
   // Returns dconn_ and nullifies dconn_.
   std::unique_ptr<DownstreamConnection> pop_downstream_connection();
@@ -332,7 +330,7 @@ public:
   void set_dispatch_state(int s);
 
   void attach_blocked_link(BlockedLink *l);
-  void detach_blocked_link(BlockedLink *l);
+  BlockedLink *detach_blocked_link();
 
   enum {
     EVENT_ERROR = 0x1,

src/shrpx_downstream_connection.h

@@ -57,6 +57,7 @@ public:
 
   virtual void on_upstream_change(Upstream *uptream) = 0;
   virtual int on_priority_change(int32_t pri) = 0;
+  virtual size_t get_group() const = 0;
 
   // true if this object is poolable.
   virtual bool poolable() const = 0;

src/shrpx_downstream_connection_pool.cc

@@ -27,33 +27,42 @@
 
 namespace shrpx {
 
-DownstreamConnectionPool::DownstreamConnectionPool() {}
+DownstreamConnectionPool::DownstreamConnectionPool(size_t num_groups)
+    : gpool_(num_groups) {}
 
 DownstreamConnectionPool::~DownstreamConnectionPool() {
-  for (auto dconn : pool_) {
+  for (auto &pool : gpool_) {
+    for (auto dconn : pool) {
       delete dconn;
     }
   }
+}
 
 void DownstreamConnectionPool::add_downstream_connection(
     std::unique_ptr<DownstreamConnection> dconn) {
-  pool_.insert(dconn.release());
+  auto group = dconn->get_group();
+  assert(gpool_.size() > group);
+  gpool_[group].insert(dconn.release());
 }
 
 std::unique_ptr<DownstreamConnection>
-DownstreamConnectionPool::pop_downstream_connection() {
+DownstreamConnectionPool::pop_downstream_connection(size_t group) {
-  if (pool_.empty()) {
+  assert(gpool_.size() > group);
+  auto &pool = gpool_[group];
+  if (pool.empty()) {
     return nullptr;
   }
 
-  auto dconn = std::unique_ptr<DownstreamConnection>(*std::begin(pool_));
+  auto dconn = std::unique_ptr<DownstreamConnection>(*std::begin(pool));
-  pool_.erase(std::begin(pool_));
+  pool.erase(std::begin(pool));
   return dconn;
 }
 
 void DownstreamConnectionPool::remove_downstream_connection(
     DownstreamConnection *dconn) {
-  pool_.erase(dconn);
+  auto group = dconn->get_group();
+  assert(gpool_.size() > group);
+  gpool_[group].erase(dconn);
   delete dconn;
 }
 

src/shrpx_downstream_connection_pool.h

@@ -36,15 +36,15 @@ class DownstreamConnection;
 
 class DownstreamConnectionPool {
 public:
-  DownstreamConnectionPool();
+  DownstreamConnectionPool(size_t num_groups);
   ~DownstreamConnectionPool();
 
   void add_downstream_connection(std::unique_ptr<DownstreamConnection> dconn);
-  std::unique_ptr<DownstreamConnection> pop_downstream_connection();
+  std::unique_ptr<DownstreamConnection> pop_downstream_connection(size_t group);
   void remove_downstream_connection(DownstreamConnection *dconn);
 
 private:
-  std::set<DownstreamConnection *> pool_;
+  std::vector<std::set<DownstreamConnection *>> gpool_;
 };
 
 } // namespace shrpx

src/shrpx_downstream_queue.cc

@@ -124,17 +124,21 @@ Downstream *DownstreamQueue::remove_and_get_blocked(Downstream *downstream) {
   // Delete downstream when this function returns.
   auto delptr = std::unique_ptr<Downstream>(downstream);
 
-  if (downstream->get_dispatch_state() != Downstream::DISPATCH_ACTIVE) {
-    assert(downstream->get_dispatch_state() != Downstream::DISPATCH_NONE);
-    downstreams_.remove(downstream);
-    return nullptr;
-  }
-
   downstreams_.remove(downstream);
 
   auto &host = make_host_key(downstream);
   auto &ent = find_host_entry(host);
+
+  if (downstream->get_dispatch_state() == Downstream::DISPATCH_ACTIVE) {
     --ent.num_active;
+  } else {
+    // For those downstreams deleted while in blocked state
+    auto link = downstream->detach_blocked_link();
+    if (link) {
+      ent.blocked.remove(link);
+      delete link;
+    }
+  }
 
   if (remove_host_entry_if_empty(ent, host_entries_, host)) {
     return nullptr;
@@ -144,22 +148,21 @@ Downstream *DownstreamQueue::remove_and_get_blocked(Downstream *downstream) {
     return nullptr;
   }
 
-  for (auto link = ent.blocked.head; link;) {
+  auto link = ent.blocked.head;
-    auto next = link->dlnext;
+
-    if (!link->downstream) {
+  if (!link) {
-      ent.blocked.remove(link);
+    return nullptr;
-      link = next;
-      continue;
   }
+
   auto next_downstream = link->downstream;
-    next_downstream->detach_blocked_link(link);
+  auto link2 = next_downstream->detach_blocked_link();
+  assert(link2 == link);
   ent.blocked.remove(link);
   delete link;
   remove_host_entry_if_empty(ent, host_entries_, host);
+
   return next_downstream;
 }
-  return nullptr;
-}
 
 Downstream *DownstreamQueue::get_downstreams() const {
   return downstreams_.head;

src/shrpx_http2_downstream_connection.cc

@@ -86,11 +86,7 @@ Http2DownstreamConnection::~Http2DownstreamConnection() {
     }
   }
   http2session_->remove_downstream_connection(this);
-  // Downstream and DownstreamConnection may be deleted
+
-  // asynchronously.
-  if (downstream_) {
-    downstream_->release_downstream_connection();
-  }
   if (LOG_ENABLED(INFO)) {
     DCLOG(INFO, this) << "Deleted";
   }
@@ -263,8 +259,11 @@ int Http2DownstreamConnection::push_request_headers() {
   // http2session_ has already in CONNECTED state, so we can get
   // addr_idx here.
   auto addr_idx = http2session_->get_addr_idx();
-  auto downstream_hostport =
+  auto group = http2session_->get_group();
-      get_config()->downstream_addrs[addr_idx].hostport.get();
+  auto downstream_hostport = get_config()
+                                 ->downstream_addr_groups[group]
+                                 .addrs[addr_idx]
+                                 .hostport.get();
 
   const char *authority = nullptr, *host = nullptr;
   if (!no_host_rewrite) {
@@ -557,4 +556,10 @@ int Http2DownstreamConnection::on_timeout() {
   return submit_rst_stream(downstream_, NGHTTP2_NO_ERROR);
 }
 
+size_t Http2DownstreamConnection::get_group() const {
+  // HTTP/2 backend connections are managed by Http2Session object,
+  // and it stores group index.
+  return http2session_->get_group();
+}
+
 } // namespace shrpx

src/shrpx_http2_downstream_connection.h

@@ -61,6 +61,7 @@ public:
 
   virtual void on_upstream_change(Upstream *upstream) {}
   virtual int on_priority_change(int32_t pri);
+  virtual size_t get_group() const;
 
   // This object is not poolable because we dont' have facility to
   // migrate to another Http2Session object.

src/shrpx_http2_session.cc

@@ -142,13 +142,14 @@ void writecb(struct ev_loop *loop, ev_io *w, int revents) {
 } // namespace
 
 Http2Session::Http2Session(struct ev_loop *loop, SSL_CTX *ssl_ctx,
-                           ConnectBlocker *connect_blocker, Worker *worker)
+                           ConnectBlocker *connect_blocker, Worker *worker,
+                           size_t group, size_t idx)
     : conn_(loop, -1, nullptr, get_config()->downstream_write_timeout,
             get_config()->downstream_read_timeout, 0, 0, 0, 0, writecb, readcb,
             timeoutcb, this),
       worker_(worker), connect_blocker_(connect_blocker), ssl_ctx_(ssl_ctx),
       session_(nullptr), data_pending_(nullptr), data_pendinglen_(0),
-      addr_idx_(0), state_(DISCONNECTED),
+      addr_idx_(0), group_(group), index_(idx), state_(DISCONNECTED),
       connection_check_state_(CONNECTION_CHECK_NONE), flow_control_(false) {
 
   read_ = write_ = &Http2Session::noop;
@@ -233,11 +234,17 @@ int Http2Session::disconnect(bool hard) {
   return 0;
 }
 
-int Http2Session::check_cert() { return ssl::check_cert(conn_.tls.ssl); }
+int Http2Session::check_cert() {
+  return ssl::check_cert(
+      conn_.tls.ssl,
+      &get_config()->downstream_addr_groups[group_].addrs[addr_idx_]);
+}
 
 int Http2Session::initiate_connection() {
   int rv = 0;
 
+  auto &addrs = get_config()->downstream_addr_groups[group_].addrs;
+
   if (state_ == DISCONNECTED) {
     if (connect_blocker_->blocked()) {
       if (LOG_ENABLED(INFO)) {
@@ -247,18 +254,19 @@ int Http2Session::initiate_connection() {
       return -1;
     }
 
-    auto worker_stat = worker_->get_worker_stat();
+    auto &next_downstream = worker_->get_dgrp(group_)->next;
-    addr_idx_ = worker_stat->next_downstream;
+    addr_idx_ = next_downstream;
-    ++worker_stat->next_downstream;
+    if (++next_downstream >= addrs.size()) {
-    worker_stat->next_downstream %= get_config()->downstream_addrs.size();
+      next_downstream = 0;
+    }
 
     if (LOG_ENABLED(INFO)) {
       SSLOG(INFO, this) << "Using downstream address idx=" << addr_idx_
-                        << " out of " << get_config()->downstream_addrs.size();
+                        << " out of " << addrs.size();
     }
   }
 
-  auto &downstream_addr = get_config()->downstream_addrs[addr_idx_];
+  auto &downstream_addr = addrs[addr_idx_];
 
   if (get_config()->downstream_http_proxy_host && state_ == DISCONNECTED) {
     if (LOG_ENABLED(INFO)) {
@@ -503,7 +511,8 @@ int Http2Session::downstream_connect_proxy() {
   if (LOG_ENABLED(INFO)) {
     SSLOG(INFO, this) << "Connected to the proxy";
   }
-  auto &downstream_addr = get_config()->downstream_addrs[addr_idx_];
+  auto &downstream_addr =
+      get_config()->downstream_addr_groups[group_].addrs[addr_idx_];
 
   std::string req = "CONNECT ";
   req += downstream_addr.hostport.get();
@@ -1744,4 +1753,8 @@ bool Http2Session::should_hard_fail() const {
 
 size_t Http2Session::get_addr_idx() const { return addr_idx_; }
 
+size_t Http2Session::get_group() const { return group_; }
+
+size_t Http2Session::get_index() const { return index_; }
+
 } // namespace shrpx

src/shrpx_http2_session.h

@@ -58,7 +58,8 @@ struct StreamData {
 class Http2Session {
 public:
   Http2Session(struct ev_loop *loop, SSL_CTX *ssl_ctx,
-               ConnectBlocker *connect_blocker, Worker *worker);
+               ConnectBlocker *connect_blocker, Worker *worker, size_t group,
+               size_t idx);
   ~Http2Session();
 
   int check_cert();
@@ -151,6 +152,10 @@ public:
 
   size_t get_addr_idx() const;
 
+  size_t get_group() const;
+
+  size_t get_index() const;
+
   enum {
     // Disconnected
     DISCONNECTED,
@@ -203,6 +208,10 @@ private:
   size_t data_pendinglen_;
   // index of get_config()->downstream_addrs this object uses
   size_t addr_idx_;
+  size_t group_;
+  // index inside group, this is used to pin frontend to certain
+  // HTTP/2 backend for better throughput.
+  size_t index_;
   int state_;
   int connection_check_state_;
   bool flow_control_;

src/shrpx_http2_upstream.cc

@@ -36,6 +36,7 @@
 #include "shrpx_config.h"
 #include "shrpx_http.h"
 #include "shrpx_worker.h"
+#include "shrpx_http2_session.h"
 #include "http2.h"
 #include "util.h"
 #include "base64.h"
@@ -300,7 +301,15 @@ int Http2Upstream::on_request_headers(Downstream *downstream,
   downstream->set_request_method(method_token);
   downstream->set_request_http2_scheme(http2::value_to_str(scheme));
   downstream->set_request_http2_authority(http2::value_to_str(authority));
+  if (path) {
+    if (get_config()->http2_proxy || get_config()->client_proxy) {
       downstream->set_request_path(http2::value_to_str(path));
+    } else {
+      auto &value = path->value;
+      downstream->set_request_path(
+          http2::rewrite_clean_path(std::begin(value), std::end(value)));
+    }
+  }
 
   if (!(frame->hd.flags & NGHTTP2_FLAG_END_STREAM)) {
     downstream->set_request_http2_expect_body(true);
@@ -334,7 +343,7 @@ void Http2Upstream::initiate_downstream(Downstream *downstream) {
   int rv;
 
   rv = downstream->attach_downstream_connection(
-      handler_->get_downstream_connection());
+      handler_->get_downstream_connection(downstream));
   if (rv != 0) {
     // downstream connection fails, send error page
     if (error_reply(downstream, 503) != 0) {
@@ -541,7 +550,8 @@ int on_frame_send_callback(nghttp2_session *session, const nghttp2_frame *frame,
             {nv.value, nv.value + nv.valuelen});
         break;
       case http2::HD__PATH:
-        downstream->set_request_path({nv.value, nv.value + nv.valuelen});
+        downstream->set_request_path(
+            http2::rewrite_clean_path(nv.value, nv.value + nv.valuelen));
         break;
       }
       downstream->add_request_header(nv.name, nv.namelen, nv.value, nv.valuelen,
@@ -874,16 +884,6 @@ ClientHandler *Http2Upstream::get_client_handler() const { return handler_; }
 int Http2Upstream::downstream_read(DownstreamConnection *dconn) {
   auto downstream = dconn->get_downstream();
 
-  if (downstream->get_request_state() == Downstream::STREAM_CLOSED) {
-    // If upstream HTTP2 stream was closed, we just close downstream,
-    // because there is no consumer now. Downstream connection is also
-    // closed in this case.
-    remove_downstream(downstream);
-    // downstream was deleted
-
-    return 0;
-  }
-
   if (downstream->get_response_state() == Downstream::MSG_RESET) {
     // The downstream stream was reset (canceled). In this case,
     // RST_STREAM to the upstream and delete downstream connection
@@ -949,14 +949,6 @@ int Http2Upstream::downstream_eof(DownstreamConnection *dconn) {
   if (LOG_ENABLED(INFO)) {
     DCLOG(INFO, dconn) << "EOF. stream_id=" << downstream->get_stream_id();
   }
-  if (downstream->get_request_state() == Downstream::STREAM_CLOSED) {
-    // If stream was closed already, we don't need to send reply at
-    // the first place. We can delete downstream.
-    remove_downstream(downstream);
-    // downstream was deleted
-
-    return 0;
-  }
 
   // Delete downstream connection. If we don't delete it here, it will
   // be pooled in on_stream_close_callback.
@@ -1002,13 +994,6 @@ int Http2Upstream::downstream_error(DownstreamConnection *dconn, int events) {
     }
   }
 
-  if (downstream->get_request_state() == Downstream::STREAM_CLOSED) {
-    remove_downstream(downstream);
-    // downstream was deleted
-
-    return 0;
-  }
-
   // Delete downstream connection. If we don't delete it here, it will
   // be pooled in on_stream_close_callback.
   downstream->pop_downstream_connection();
@@ -1476,7 +1461,7 @@ int Http2Upstream::on_downstream_reset(bool no_retry) {
     // downstream connection.
 
     rv = downstream->attach_downstream_connection(
-        handler_->get_downstream_connection());
+        handler_->get_downstream_connection(downstream));
     if (rv != 0) {
       goto fail;
     }

src/shrpx_http_downstream_connection.cc

@@ -34,6 +34,7 @@
 #include "shrpx_connect_blocker.h"
 #include "shrpx_downstream_connection_pool.h"
 #include "shrpx_worker.h"
+#include "shrpx_http2_session.h"
 #include "http2.h"
 #include "util.h"
 
@@ -109,21 +110,15 @@ void connectcb(struct ev_loop *loop, ev_io *w, int revents) {
 } // namespace
 
 HttpDownstreamConnection::HttpDownstreamConnection(
-    DownstreamConnectionPool *dconn_pool, struct ev_loop *loop)
+    DownstreamConnectionPool *dconn_pool, size_t group, struct ev_loop *loop)
     : DownstreamConnection(dconn_pool),
       conn_(loop, -1, nullptr, get_config()->downstream_write_timeout,
             get_config()->downstream_read_timeout, 0, 0, 0, 0, connectcb,
             readcb, timeoutcb, this),
-      ioctrl_(&conn_.rlimit), response_htp_{0}, addr_idx_(0),
+      ioctrl_(&conn_.rlimit), response_htp_{0}, group_(group), addr_idx_(0),
       connected_(false) {}
 
-HttpDownstreamConnection::~HttpDownstreamConnection() {
+HttpDownstreamConnection::~HttpDownstreamConnection() {}
-  // Downstream and DownstreamConnection may be deleted
-  // asynchronously.
-  if (downstream_) {
-    downstream_->release_downstream_connection();
-  }
-}
 
 int HttpDownstreamConnection::attach_downstream(Downstream *downstream) {
   if (LOG_ENABLED(INFO)) {
@@ -142,15 +137,17 @@ int HttpDownstreamConnection::attach_downstream(Downstream *downstream) {
     }
 
     auto worker = client_handler_->get_worker();
-    auto worker_stat = worker->get_worker_stat();
+    auto &next_downstream = worker->get_dgrp(group_)->next;
-    auto end = worker_stat->next_downstream;
+    auto end = next_downstream;
+    auto &addrs = get_config()->downstream_addr_groups[group_].addrs;
     for (;;) {
-      auto i = worker_stat->next_downstream;
+      auto &addr = addrs[next_downstream];
-      ++worker_stat->next_downstream;
+      auto i = next_downstream;
-      worker_stat->next_downstream %= get_config()->downstream_addrs.size();
+      if (++next_downstream >= addrs.size()) {
+        next_downstream = 0;
+      }
 
-      conn_.fd = util::create_nonblock_socket(
+      conn_.fd = util::create_nonblock_socket(addr.addr.storage.ss_family);
-          get_config()->downstream_addrs[i].addr.storage.ss_family);
 
       if (conn_.fd == -1) {
         auto error = errno;
@@ -162,8 +159,7 @@ int HttpDownstreamConnection::attach_downstream(Downstream *downstream) {
       }
 
       int rv;
-      rv = connect(conn_.fd, &get_config()->downstream_addrs[i].addr.sa,
+      rv = connect(conn_.fd, &addr.addr.sa, addr.addrlen);
-                   get_config()->downstream_addrs[i].addrlen);
       if (rv != 0 && errno != EINPROGRESS) {
         auto error = errno;
         DCLOG(WARN, this) << "connect() failed; errno=" << error;
@@ -172,7 +168,7 @@ int HttpDownstreamConnection::attach_downstream(Downstream *downstream) {
         close(conn_.fd);
         conn_.fd = -1;
 
-        if (end == worker_stat->next_downstream) {
+        if (end == next_downstream) {
           return SHRPX_ERR_NETWORK;
         }
 
@@ -203,6 +199,8 @@ int HttpDownstreamConnection::attach_downstream(Downstream *downstream) {
   ev_set_cb(&conn_.rev, readcb);
 
   conn_.rt.repeat = get_config()->downstream_read_timeout;
+  // we may set read timer cb to idle_timeoutcb.  Reset again.
+  ev_set_cb(&conn_.rt, timeoutcb);
   ev_timer_again(conn_.loop, &conn_.rt);
   // TODO we should have timeout for connection establishment
   ev_timer_again(conn_.loop, &conn_.wt);
@@ -212,8 +210,10 @@ int HttpDownstreamConnection::attach_downstream(Downstream *downstream) {
 
 int HttpDownstreamConnection::push_request_headers() {
   const char *authority = nullptr, *host = nullptr;
-  auto downstream_hostport =
+  auto downstream_hostport = get_config()
-      get_config()->downstream_addrs[addr_idx_].hostport.get();
+                                 ->downstream_addr_groups[group_]
+                                 .addrs[addr_idx_]
+                                 .hostport.get();
   auto connect_method = downstream_->get_request_method() == HTTP_CONNECT;
 
   if (!get_config()->no_host_rewrite && !get_config()->http2_proxy &&
@@ -860,6 +860,8 @@ int HttpDownstreamConnection::on_connect() {
       DLOG(INFO, this) << "downstream connect failed";
     }
 
+    downstream_->set_request_state(Downstream::CONNECT_FAIL);
+
     return -1;
   }
 
@@ -877,4 +879,6 @@ void HttpDownstreamConnection::on_upstream_change(Upstream *upstream) {}
 
 void HttpDownstreamConnection::signal_write() { conn_.wlimit.startw(); }
 
+size_t HttpDownstreamConnection::get_group() const { return group_; }
+
 } // namespace shrpx

src/shrpx_http_downstream_connection.h

@@ -39,7 +39,7 @@ class DownstreamConnectionPool;
 
 class HttpDownstreamConnection : public DownstreamConnection {
 public:
-  HttpDownstreamConnection(DownstreamConnectionPool *dconn_pool,
+  HttpDownstreamConnection(DownstreamConnectionPool *dconn_pool, size_t group,
                            struct ev_loop *loop);
   virtual ~HttpDownstreamConnection();
   virtual int attach_downstream(Downstream *downstream);
@@ -58,6 +58,7 @@ public:
 
   virtual void on_upstream_change(Upstream *upstream);
   virtual int on_priority_change(int32_t pri) { return 0; }
+  virtual size_t get_group() const;
 
   virtual bool poolable() const { return true; }
 
@@ -68,6 +69,7 @@ private:
   Connection conn_;
   IOControl ioctrl_;
   http_parser response_htp_;
+  size_t group_;
   // index of get_config()->downstream_addrs this object is using
   size_t addr_idx_;
   bool connected_;

src/shrpx_https_upstream.cc

@@ -36,6 +36,7 @@
 #include "shrpx_error.h"
 #include "shrpx_log_config.h"
 #include "shrpx_worker.h"
+#include "shrpx_http2_session.h"
 #include "http2.h"
 #include "util.h"
 #include "template.h"
@@ -218,7 +219,12 @@ void rewrite_request_host_path_from_uri(Downstream *downstream, const char *uri,
     path += '?';
     path.append(uri + fdata.off, fdata.len);
   }
+  if (get_config()->http2_proxy || get_config()->client_proxy) {
     downstream->set_request_path(std::move(path));
+  } else {
+    downstream->set_request_path(
+        http2::rewrite_clean_path(std::begin(path), std::end(path)));
+  }
 
   std::string scheme;
   http2::copy_url_component(scheme, &u, UF_SCHEMA, uri);
@@ -286,6 +292,9 @@ int htp_hdrs_completecb(http_parser *htp) {
         return -1;
       }
 
+      downstream->set_request_path(
+          http2::rewrite_clean_path(std::begin(uri), std::end(uri)));
+
       if (upstream->get_client_handler()->get_ssl()) {
         downstream->set_request_http2_scheme("https");
       } else {
@@ -297,7 +306,7 @@ int htp_hdrs_completecb(http_parser *htp) {
   }
 
   rv = downstream->attach_downstream_connection(
-      upstream->get_client_handler()->get_downstream_connection());
+      upstream->get_client_handler()->get_downstream_connection(downstream));
 
   if (rv != 0) {
     downstream->set_request_state(Downstream::CONNECT_FAIL);
@@ -993,7 +1002,7 @@ int HttpsUpstream::on_downstream_reset(bool no_retry) {
   }
 
   rv = downstream_->attach_downstream_connection(
-      handler_->get_downstream_connection());
+      handler_->get_downstream_connection(downstream_.get()));
   if (rv != 0) {
     goto fail;
   }

src/shrpx_log.h

@@ -123,6 +123,8 @@ enum LogFragmentType {
 };
 
 struct LogFragment {
+  LogFragment(LogFragmentType type, std::unique_ptr<char[]> value = nullptr)
+      : type(type), value(std::move(value)) {}
   LogFragmentType type;
   std::unique_ptr<char[]> value;
 };

src/shrpx_spdy_upstream.cc

@@ -229,7 +229,12 @@ void on_ctrl_recv_callback(spdylay_session *session, spdylay_frame_type type,
     } else {
       downstream->set_request_http2_scheme(scheme->value);
       downstream->set_request_http2_authority(host->value);
+      if (get_config()->http2_proxy || get_config()->client_proxy) {
         downstream->set_request_path(path->value);
+      } else {
+        downstream->set_request_path(http2::rewrite_clean_path(
+            std::begin(path->value), std::end(path->value)));
+      }
     }
 
     if (!(frame->syn_stream.hd.flags & SPDYLAY_CTRL_FLAG_FIN)) {
@@ -271,7 +276,7 @@ void SpdyUpstream::start_downstream(Downstream *downstream) {
 
 void SpdyUpstream::initiate_downstream(Downstream *downstream) {
   int rv = downstream->attach_downstream_connection(
-      handler_->get_downstream_connection());
+      handler_->get_downstream_connection(downstream));
   if (rv != 0) {
     // If downstream connection fails, issue RST_STREAM.
     rst_stream(downstream, SPDYLAY_INTERNAL_ERROR);
@@ -555,16 +560,6 @@ ClientHandler *SpdyUpstream::get_client_handler() const { return handler_; }
 int SpdyUpstream::downstream_read(DownstreamConnection *dconn) {
   auto downstream = dconn->get_downstream();
 
-  if (downstream->get_request_state() == Downstream::STREAM_CLOSED) {
-    // If upstream SPDY stream was closed, we just close downstream,
-    // because there is no consumer now. Downstream connection is also
-    // closed in this case.
-    remove_downstream(downstream);
-    // downstrea was deleted
-
-    return 0;
-  }
-
   if (downstream->get_response_state() == Downstream::MSG_RESET) {
     // The downstream stream was reset (canceled). In this case,
     // RST_STREAM to the upstream and delete downstream connection
@@ -628,14 +623,6 @@ int SpdyUpstream::downstream_eof(DownstreamConnection *dconn) {
   if (LOG_ENABLED(INFO)) {
     DCLOG(INFO, dconn) << "EOF. stream_id=" << downstream->get_stream_id();
   }
-  if (downstream->get_request_state() == Downstream::STREAM_CLOSED) {
-    // If stream was closed already, we don't need to send reply at
-    // the first place. We can delete downstream.
-    remove_downstream(downstream);
-    // downstream was deleted
-
-    return 0;
-  }
 
   // Delete downstream connection. If we don't delete it here, it will
   // be pooled in on_stream_close_callback.
@@ -681,13 +668,6 @@ int SpdyUpstream::downstream_error(DownstreamConnection *dconn, int events) {
     }
   }
 
-  if (downstream->get_request_state() == Downstream::STREAM_CLOSED) {
-    remove_downstream(downstream);
-    // downstream was deleted
-
-    return 0;
-  }
-
   // Delete downstream connection. If we don't delete it here, it will
   // be pooled in on_stream_close_callback.
   downstream->pop_downstream_connection();
@@ -1104,7 +1084,7 @@ int SpdyUpstream::on_downstream_reset(bool no_retry) {
     // downstream connection.
 
     rv = downstream->attach_downstream_connection(
-        handler_->get_downstream_connection());
+        handler_->get_downstream_connection(downstream));
     if (rv != 0) {
       goto fail;
     }

src/shrpx_ssl.cc

@@ -53,6 +53,7 @@
 #include "shrpx_config.h"
 #include "shrpx_worker.h"
 #include "shrpx_downstream_connection_pool.h"
+#include "shrpx_http2_session.h"
 #include "util.h"
 #include "ssl.h"
 #include "template.h"
@@ -743,7 +744,7 @@ void get_altnames(X509 *cert, std::vector<std::string> &dns_names,
   }
 }
 
-int check_cert(SSL *ssl) {
+int check_cert(SSL *ssl, const DownstreamAddr *addr) {
   auto cert = SSL_get_peer_certificate(ssl);
   if (!cert) {
     LOG(ERROR) << "No certificate found";
@@ -760,9 +761,7 @@ int check_cert(SSL *ssl) {
   std::vector<std::string> dns_names;
   std::vector<std::string> ip_addrs;
   get_altnames(cert, dns_names, ip_addrs, common_name);
-  if (verify_hostname(get_config()->downstream_addrs[0].host.get(),
+  if (verify_hostname(addr->host.get(), &addr->addr, addr->addrlen, dns_names,
-                      &get_config()->downstream_addrs[0].addr,
-                      get_config()->downstream_addrs[0].addrlen, dns_names,
                       ip_addrs, common_name) != 0) {
     LOG(ERROR) << "Certificate verification failed: hostname does not match";
     return -1;

src/shrpx_ssl.h

@@ -40,6 +40,7 @@ namespace shrpx {
 class ClientHandler;
 class Worker;
 class DownstreamConnectionPool;
+struct DownstreamAddr;
 
 namespace ssl {
 
@@ -68,7 +69,7 @@ ClientHandler *accept_connection(Worker *worker, int fd, sockaddr *addr,
 // Check peer's certificate against first downstream address in
 // Config::downstream_addrs.  We only consider first downstream since
 // we use this function for HTTP/2 downstream link only.
-int check_cert(SSL *ssl);
+int check_cert(SSL *ssl, const DownstreamAddr *addr);
 
 // Retrieves DNS and IP address in subjectAltNames and commonName from
 // the |cert|.

src/shrpx_worker.cc

@@ -61,8 +61,11 @@ void mcpool_clear_cb(struct ev_loop *loop, ev_timer *w, int revents) {
 Worker::Worker(struct ev_loop *loop, SSL_CTX *sv_ssl_ctx, SSL_CTX *cl_ssl_ctx,
                ssl::CertLookupTree *cert_tree,
                const std::shared_ptr<TicketKeys> &ticket_keys)
-    : next_http2session_(0), loop_(loop), sv_ssl_ctx_(sv_ssl_ctx),
+    : dconn_pool_(get_config()->downstream_addr_groups.size()),
-      cl_ssl_ctx_(cl_ssl_ctx), cert_tree_(cert_tree), ticket_keys_(ticket_keys),
+      worker_stat_(get_config()->downstream_addr_groups.size()),
+      dgrps_(get_config()->downstream_addr_groups.size()), loop_(loop),
+      sv_ssl_ctx_(sv_ssl_ctx), cl_ssl_ctx_(cl_ssl_ctx), cert_tree_(cert_tree),
+      ticket_keys_(ticket_keys),
       connect_blocker_(make_unique<ConnectBlocker>(loop_)),
       graceful_shutdown_(false) {
   ev_async_init(&w_, eventcb);
@@ -74,9 +77,17 @@ Worker::Worker(struct ev_loop *loop, SSL_CTX *sv_ssl_ctx, SSL_CTX *cl_ssl_ctx,
 
   if (get_config()->downstream_proto == PROTO_HTTP2) {
     auto n = get_config()->http2_downstream_connections_per_worker;
-    for (; n > 0; --n) {
+    size_t group = 0;
-      http2sessions_.push_back(make_unique<Http2Session>(
+    for (auto &dgrp : dgrps_) {
-          loop_, cl_ssl_ctx, connect_blocker_.get(), this));
+      auto m = n;
+      if (m == 0) {
+        m = get_config()->downstream_addr_groups[group].addrs.size();
+      }
+      for (size_t idx = 0; idx < m; ++idx) {
+        dgrp.http2sessions.push_back(make_unique<Http2Session>(
+            loop_, cl_ssl_ctx, connect_blocker_.get(), this, group, idx));
+      }
+      ++group;
     }
   }
 }
@@ -207,15 +218,17 @@ WorkerStat *Worker::get_worker_stat() { return &worker_stat_; }
 
 DownstreamConnectionPool *Worker::get_dconn_pool() { return &dconn_pool_; }
 
-Http2Session *Worker::next_http2_session() {
+Http2Session *Worker::next_http2_session(size_t group) {
-  if (http2sessions_.empty()) {
+  auto &dgrp = dgrps_[group];
+  auto &http2sessions = dgrp.http2sessions;
+  if (http2sessions.empty()) {
     return nullptr;
   }
 
-  auto res = http2sessions_[next_http2session_].get();
+  auto res = http2sessions[dgrp.next_http2session].get();
-  ++next_http2session_;
+  ++dgrp.next_http2session;
-  if (next_http2session_ >= http2sessions_.size()) {
+  if (dgrp.next_http2session >= http2sessions.size()) {
-    next_http2session_ = 0;
+    dgrp.next_http2session = 0;
   }
 
   return res;
@@ -239,4 +252,9 @@ bool Worker::get_graceful_shutdown() const { return graceful_shutdown_; }
 
 MemchunkPool *Worker::get_mcpool() { return &mcpool_; }
 
+DownstreamGroup *Worker::get_dgrp(size_t group) {
+  assert(group < dgrps_.size());
+  return &dgrps_[group];
+}
+
 } // namespace shrpx

src/shrpx_worker.h

@@ -54,14 +54,21 @@ namespace ssl {
 class CertLookupTree;
 } // namespace ssl
 
+struct DownstreamGroup {
+  DownstreamGroup() : next_http2session(0), next(0) {}
+
+  std::vector<std::unique_ptr<Http2Session>> http2sessions;
+  // Next index in http2sessions.
+  size_t next_http2session;
+  // Next downstream address index corresponding to
+  // Config::downstream_addr_groups[].
+  size_t next;
+};
+
 struct WorkerStat {
-  WorkerStat() : num_connections(0), next_downstream(0) {}
+  WorkerStat(size_t num_groups) : num_connections(0) {}
 
   size_t num_connections;
-  // Next downstream index in Config::downstream_addrs.  For HTTP/2
-  // downstream connections, this is always 0.  For HTTP/1, this is
-  // used as load balancing.
-  size_t next_downstream;
 };
 
 enum WorkerEventType {
@@ -97,7 +104,7 @@ public:
   void set_ticket_keys(std::shared_ptr<TicketKeys> ticket_keys);
   WorkerStat *get_worker_stat();
   DownstreamConnectionPool *get_dconn_pool();
-  Http2Session *next_http2_session();
+  Http2Session *next_http2_session(size_t group);
   ConnectBlocker *get_connect_blocker() const;
   struct ev_loop *get_loop() const;
   SSL_CTX *get_sv_ssl_ctx() const;
@@ -109,9 +116,9 @@ public:
   MemchunkPool *get_mcpool();
   void schedule_clear_mcpool();
 
+  DownstreamGroup *get_dgrp(size_t group);
+
 private:
-  std::vector<std::unique_ptr<Http2Session>> http2sessions_;
-  size_t next_http2session_;
 #ifndef NOTHREADS
   std::future<void> fut_;
 #endif // NOTHREADS
@@ -122,6 +129,7 @@ private:
   MemchunkPool mcpool_;
   DownstreamConnectionPool dconn_pool_;
   WorkerStat worker_stat_;
+  std::vector<DownstreamGroup> dgrps_;
   struct ev_loop *loop_;
 
   // Following fields are shared across threads if

src/timegm.c

@@ -34,7 +34,7 @@ static int count_leap_year(int y) {
 }
 
 /* Based on the algorithm of Python 2.7 calendar.timegm. */
-time_t timegm(struct tm *tm) {
+time_t nghttp2_timegm(struct tm *tm) {
   int days;
   int num_leap_year;
   int64_t t;

src/timegm.h

@@ -37,7 +37,7 @@ extern "C" {
 #include <time.h>
 #endif // HAVE_TIME_H
 
-time_t timegm(struct tm *tm);
+time_t nghttp2_timegm(struct tm *tm);
 
 #ifdef __cplusplus
 }

src/util.cc

@@ -278,7 +278,7 @@ std::string common_log_date(time_t t) {
 #ifdef HAVE_STRUCT_TM_TM_GMTOFF
   auto gmtoff = tms.tm_gmtoff;
 #else  // !HAVE_STRUCT_TM_TM_GMTOFF
-  auto gmtoff = timegm(&tms) - t;
+  auto gmtoff = nghttp2_timegm(&tms) - t;
 #endif // !HAVE_STRUCT_TM_TM_GMTOFF
   if (gmtoff >= 0) {
     *p++ = '+';
@@ -326,7 +326,7 @@ std::string iso8601_date(int64_t ms) {
 #ifdef HAVE_STRUCT_TM_TM_GMTOFF
   auto gmtoff = tms.tm_gmtoff;
 #else  // !HAVE_STRUCT_TM_TM_GMTOFF
-  auto gmtoff = timegm(&tms) - sec;
+  auto gmtoff = nghttp2_timegm(&tms) - sec;
 #endif // !HAVE_STRUCT_TM_TM_GMTOFF
   if (gmtoff == 0) {
     *p++ = 'Z';
@@ -354,7 +354,7 @@ time_t parse_http_date(const std::string &s) {
   if (r == 0) {
     return 0;
   }
-  return timegm(&tm);
+  return nghttp2_timegm(&tm);
 }
 
 namespace {

src/util.h

@@ -386,9 +386,13 @@ bool streq_l(const char (&a)[N], InputIt b, size_t blen) {
 
 bool strifind(const char *a, const char *b);
 
+template <typename InputIt> void inp_strlower(InputIt first, InputIt last) {
+  std::transform(first, last, first, lowcase);
+}
+
 // Lowercase |s| in place.
 inline void inp_strlower(std::string &s) {
-  std::transform(std::begin(s), std::end(s), std::begin(s), lowcase);
+  inp_strlower(std::begin(s), std::end(s));
 }
 
 // Returns string representation of |n| with 2 fractional digits.