Merge branch 'master' into http2-push

Since we do prefix match using given header by application code
against header name pair in format "NAME:VALUE", and VALUE part can
contain ":", we have to careful about existence of ":" in header
parameter.  ":" should be allowed to match HTTP/2 pseudo-header field,
and other use of ":" in header must be treated as error, and
curl_pushheader_byname should return NULL.  This commit implements
this behaviour.

docs/examples/Makefile.inc

@@ -32,7 +32,7 @@ check_PROGRAMS = 10-at-a-time anyauthput cookie_interface debug fileupload \
   imap-list imap-lsub imap-fetch imap-store imap-append imap-examine       \
   imap-search imap-create imap-delete imap-copy imap-noop imap-ssl         \
   imap-tls imap-multi url2file sftpget ftpsget postinmemory http2-download \
-  http2-upload
+  http2-upload http2-serverpush
 
 # These examples require external dependencies that may not be commonly
 # available on POSIX systems, so don't bother attempting to compile them here.

docs/examples/http2-serverpush.c

@@ -0,0 +1,313 @@
+/***************************************************************************
+ *                                  _   _ ____  _
+ *  Project                     ___| | | |  _ \| |
+ *                             / __| | | | |_) | |
+ *                            | (__| |_| |  _ <| |___
+ *                             \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) 1998 - 2015, Daniel Stenberg, <daniel@haxx.se>, et al.
+ *
+ * This software is licensed as described in the file COPYING, which
+ * you should have received as part of this distribution. The terms
+ * are also available at http://curl.haxx.se/docs/copyright.html.
+ *
+ * You may opt to use, copy, modify, merge, publish, distribute and/or sell
+ * copies of the Software, and permit persons to whom the Software is
+ * furnished to do so, under the terms of the COPYING file.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ***************************************************************************/
+#include <stdio.h>
+#include <stdlib.h>
+
+/* somewhat unix-specific */
+#include <sys/time.h>
+#include <unistd.h>
+
+/* curl stuff */
+#include <curl/curl.h>
+
+#ifndef CURLPIPE_MULTIPLEX
+#error "too old libcurl, can't do HTTP/2 server push!"
+#endif
+
+static
+void dump(const char *text, unsigned char *ptr, size_t size,
+          char nohex)
+{
+  size_t i;
+  size_t c;
+
+  unsigned int width=0x10;
+
+  if(nohex)
+    /* without the hex output, we can fit more on screen */
+    width = 0x40;
+
+  fprintf(stderr, "%s, %ld bytes (0x%lx)\n",
+          text, (long)size, (long)size);
+
+  for(i=0; i<size; i+= width) {
+
+    fprintf(stderr, "%4.4lx: ", (long)i);
+
+    if(!nohex) {
+      /* hex not disabled, show it */
+      for(c = 0; c < width; c++)
+        if(i+c < size)
+          fprintf(stderr, "%02x ", ptr[i+c]);
+        else
+          fputs("   ", stderr);
+    }
+
+    for(c = 0; (c < width) && (i+c < size); c++) {
+      /* check for 0D0A; if found, skip past and start a new line of output */
+      if (nohex && (i+c+1 < size) && ptr[i+c]==0x0D && ptr[i+c+1]==0x0A) {
+        i+=(c+2-width);
+        break;
+      }
+      fprintf(stderr, "%c",
+              (ptr[i+c]>=0x20) && (ptr[i+c]<0x80)?ptr[i+c]:'.');
+      /* check again for 0D0A, to avoid an extra \n if it's at width */
+      if (nohex && (i+c+2 < size) && ptr[i+c+1]==0x0D && ptr[i+c+2]==0x0A) {
+        i+=(c+3-width);
+        break;
+      }
+    }
+    fputc('\n', stderr); /* newline */
+  }
+}
+
+static
+int my_trace(CURL *handle, curl_infotype type,
+             char *data, size_t size,
+             void *userp)
+{
+  const char *text;
+  (void)handle; /* prevent compiler warning */
+  (void)userp;
+  switch (type) {
+  case CURLINFO_TEXT:
+    fprintf(stderr, "== Info: %s", data);
+  default: /* in case a new one is introduced to shock us */
+    return 0;
+
+  case CURLINFO_HEADER_OUT:
+    text = "=> Send header";
+    break;
+  case CURLINFO_DATA_OUT:
+    text = "=> Send data";
+    break;
+  case CURLINFO_SSL_DATA_OUT:
+    text = "=> Send SSL data";
+    break;
+  case CURLINFO_HEADER_IN:
+    text = "<= Recv header";
+    break;
+  case CURLINFO_DATA_IN:
+    text = "<= Recv data";
+    break;
+  case CURLINFO_SSL_DATA_IN:
+    text = "<= Recv SSL data";
+    break;
+  }
+
+  dump(text, (unsigned char *)data, size, 1);
+  return 0;
+}
+
+static void setup(CURL *hnd)
+{
+  FILE *out = fopen("dl", "wb");
+
+  /* write to this file */
+  curl_easy_setopt(hnd, CURLOPT_WRITEDATA, out);
+
+  /* set the same URL */
+  curl_easy_setopt(hnd, CURLOPT_URL, "https://localhost:8443/index.html");
+
+  /* send it verbose for max debuggaility */
+  curl_easy_setopt(hnd, CURLOPT_VERBOSE, 1L);
+  curl_easy_setopt(hnd, CURLOPT_DEBUGFUNCTION, my_trace);
+
+  /* HTTP/2 please */
+  curl_easy_setopt(hnd, CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_2_0);
+
+  /* we use a self-signed test server, skip verification during debugging */
+  curl_easy_setopt(hnd, CURLOPT_SSL_VERIFYPEER, 0L);
+  curl_easy_setopt(hnd, CURLOPT_SSL_VERIFYHOST, 0L);
+
+#if (CURLPIPE_MULTIPLEX > 0)
+  /* wait for pipe connection to confirm */
+  curl_easy_setopt(hnd, CURLOPT_PIPEWAIT, 1L);
+#endif
+
+}
+
+/* called when there's an incoming push */
+static int server_push_callback(CURL *parent,
+                                CURL *easy,
+                                size_t num_headers,
+                                struct curl_pushheaders *headers,
+                                void *userp)
+{
+  char *headp;
+  size_t i;
+  int *transfers = (int *)userp;
+  char filename[128];
+  FILE *out;
+  static unsigned int count = 0;
+
+  (void)parent; /* we have no use for this */
+
+  sprintf(filename, "push%u", count++);
+
+  /* here's a new stream, save it in a new file for each new push */
+  out = fopen(filename, "wb");
+
+  /* write to this file */
+  curl_easy_setopt(easy, CURLOPT_WRITEDATA, out);
+
+  fprintf(stderr, "**** push callback approves stream %u, got %d headers!\n",
+          count, (int)num_headers);
+
+  for(i=0; i<num_headers; i++) {
+    headp = curl_pushheader_bynum(headers, i);
+    fprintf(stderr, "**** header %u: %s\n", (int)i, headp);
+  }
+
+  headp = curl_pushheader_byname(headers, ":path");
+  if(headp) {
+    fprintf(stderr, "**** The PATH is %s\n", headp /* skip :path + colon */ );
+  }
+
+  (*transfers)++; /* one more */
+  return CURL_PUSH_OK;
+}
+
+
+/*
+ * Download a file over HTTP/2, take care of server push.
+ */
+int main(void)
+{
+  CURL *easy;
+  CURLM *multi_handle;
+  int still_running; /* keep number of running handles */
+  int transfers=1; /* we start with one */
+  struct CURLMsg *m;
+
+  /* init a multi stack */
+  multi_handle = curl_multi_init();
+
+  easy = curl_easy_init();
+
+  /* set options */
+  setup(easy);
+
+  /* add the easy transfer */
+  curl_multi_add_handle(multi_handle, easy);
+
+  curl_multi_setopt(multi_handle, CURLMOPT_PIPELINING, CURLPIPE_MULTIPLEX);
+  curl_multi_setopt(multi_handle, CURLMOPT_PUSHFUNCTION, server_push_callback);
+  curl_multi_setopt(multi_handle, CURLMOPT_PUSHDATA, &transfers);
+
+  /* we start some action by calling perform right away */
+  curl_multi_perform(multi_handle, &still_running);
+
+  do {
+    struct timeval timeout;
+    int rc; /* select() return code */
+    CURLMcode mc; /* curl_multi_fdset() return code */
+
+    fd_set fdread;
+    fd_set fdwrite;
+    fd_set fdexcep;
+    int maxfd = -1;
+
+    long curl_timeo = -1;
+
+    FD_ZERO(&fdread);
+    FD_ZERO(&fdwrite);
+    FD_ZERO(&fdexcep);
+
+    /* set a suitable timeout to play around with */
+    timeout.tv_sec = 1;
+    timeout.tv_usec = 0;
+
+    curl_multi_timeout(multi_handle, &curl_timeo);
+    if(curl_timeo >= 0) {
+      timeout.tv_sec = curl_timeo / 1000;
+      if(timeout.tv_sec > 1)
+        timeout.tv_sec = 1;
+      else
+        timeout.tv_usec = (curl_timeo % 1000) * 1000;
+    }
+
+    /* get file descriptors from the transfers */
+    mc = curl_multi_fdset(multi_handle, &fdread, &fdwrite, &fdexcep, &maxfd);
+
+    if(mc != CURLM_OK) {
+      fprintf(stderr, "curl_multi_fdset() failed, code %d.\n", mc);
+      break;
+    }
+
+    /* On success the value of maxfd is guaranteed to be >= -1. We call
+       select(maxfd + 1, ...); specially in case of (maxfd == -1) there are
+       no fds ready yet so we call select(0, ...) --or Sleep() on Windows--
+       to sleep 100ms, which is the minimum suggested value in the
+       curl_multi_fdset() doc. */
+
+    if(maxfd == -1) {
+#ifdef _WIN32
+      Sleep(100);
+      rc = 0;
+#else
+      /* Portable sleep for platforms other than Windows. */
+      struct timeval wait = { 0, 100 * 1000 }; /* 100ms */
+      rc = select(0, NULL, NULL, NULL, &wait);
+#endif
+    }
+    else {
+      /* Note that on some platforms 'timeout' may be modified by select().
+         If you need access to the original value save a copy beforehand. */
+      rc = select(maxfd+1, &fdread, &fdwrite, &fdexcep, &timeout);
+    }
+
+    switch(rc) {
+    case -1:
+      /* select error */
+      break;
+    case 0:
+    default:
+      /* timeout or readable/writable sockets */
+      curl_multi_perform(multi_handle, &still_running);
+      break;
+    }
+
+    /*
+     * A little caution when doing server push is that libcurl itself has
+     * created and added one or more easy handles but we need to clean them up
+     * when we are done.
+     */
+
+    do {
+      int msgq = 0;;
+      m = curl_multi_info_read(multi_handle, &msgq);
+      if(m && (m->msg == CURLMSG_DONE)) {
+        CURL *e = m->easy_handle;
+        transfers--;
+        curl_multi_remove_handle(multi_handle, e);
+        curl_easy_cleanup(e);
+      }
+    } while(m);
+
+  } while(transfers); /* as long as we have transfers going */
+
+  curl_multi_cleanup(multi_handle);
+
+
+  return 0;
+}

docs/libcurl/opts/CURLMOPT_PUSHDATA.3

@@ -0,0 +1,49 @@
+.\" **************************************************************************
+.\" *                                  _   _ ____  _
+.\" *  Project                     ___| | | |  _ \| |
+.\" *                             / __| | | | |_) | |
+.\" *                            | (__| |_| |  _ <| |___
+.\" *                             \___|\___/|_| \_\_____|
+.\" *
+.\" * Copyright (C) 1998 - 2015, Daniel Stenberg, <daniel@haxx.se>, et al.
+.\" *
+.\" * This software is licensed as described in the file COPYING, which
+.\" * you should have received as part of this distribution. The terms
+.\" * are also available at http://curl.haxx.se/docs/copyright.html.
+.\" *
+.\" * You may opt to use, copy, modify, merge, publish, distribute and/or sell
+.\" * copies of the Software, and permit persons to whom the Software is
+.\" * furnished to do so, under the terms of the COPYING file.
+.\" *
+.\" * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+.\" * KIND, either express or implied.
+.\" *
+.\" **************************************************************************
+.\"
+.TH CURLMOPT_PUSHDATA 3 "1 Jun 2015" "libcurl 7.44.0" "curl_multi_setopt options"
+.SH NAME
+CURLMOPT_PUSHDATA \- pointer to pass to push callback
+.SH SYNOPSIS
+.nf
+#include <curl/curl.h>
+
+CURLMcode curl_multi_setopt(CURLM *handle, CURLMOPT_PUSHDATA, void *pointer);
+.fi
+.SH DESCRIPTION
+Set \fIpointer\fP to pass as the last argument to the
+\fICURLMOPT_PUSHFUNCTION(3)\fP callback. The pointer will not be touched or
+used by libcurl itself, only passed on to the callback function.
+.SH DEFAULT
+NULL
+.SH PROTOCOLS
+HTTP(S)
+.SH EXAMPLE
+TODO
+.SH AVAILABILITY
+Added in 7.44.0
+.SH RETURN VALUE
+Returns CURLM_OK if the option is supported, and CURLM_UNKNOWN_OPTION if not.
+.SH "SEE ALSO"
+.BR CURLMOPT_PUSHFUNCTION "(3), " CURLMOPT_PIPELINING "(3), "
+.BR CURLOPT_PIPEWAIT "(3), "
+.BR RFC 7540

docs/libcurl/opts/CURLMOPT_PUSHFUNCTION.3

@@ -0,0 +1,132 @@
+.\" **************************************************************************
+.\" *                                  _   _ ____  _
+.\" *  Project                     ___| | | |  _ \| |
+.\" *                             / __| | | | |_) | |
+.\" *                            | (__| |_| |  _ <| |___
+.\" *                             \___|\___/|_| \_\_____|
+.\" *
+.\" * Copyright (C) 1998 - 2015, Daniel Stenberg, <daniel@haxx.se>, et al.
+.\" *
+.\" * This software is licensed as described in the file COPYING, which
+.\" * you should have received as part of this distribution. The terms
+.\" * are also available at http://curl.haxx.se/docs/copyright.html.
+.\" *
+.\" * You may opt to use, copy, modify, merge, publish, distribute and/or sell
+.\" * copies of the Software, and permit persons to whom the Software is
+.\" * furnished to do so, under the terms of the COPYING file.
+.\" *
+.\" * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+.\" * KIND, either express or implied.
+.\" *
+.\" **************************************************************************
+.\"
+.TH CURLMOPT_PUSHFUNCTION 3 "1 Jun 2015" "libcurl 7.44.0" "curl_multi_setopt options"
+.SH NAME
+CURLMOPT_PUSHFUNCTION \- callback that approves or denies server pushes
+.SH SYNOPSIS
+.nf
+#include <curl/curl.h>
+
+char *curl_pushheader_bynum(push_headers, int num);
+char *curl_pushheader_byname(push_headers, const char *name);
+
+int curl_push_callback(CURL *parent,
+                       CURL *easy,
+                       size_t num_headers,
+                       struct curl_pushheaders *headers,
+                       void *userp);
+
+CURLMcode curl_multi_setopt(CURLM *handle, CURLMOPT_PUSHFUNCTION,
+                            curl_push_callback func);
+.fi
+.SH DESCRIPTION
+This callback gets called when a new HTTP/2 stream is being pushed by the
+server (using the PUSH_PROMISE frame). If no push callback is set, all offered
+pushes will be denied automatically.
+.SH CALLBACK DESCRIPTION
+The callback gets its arguments like this:
+
+\fIparent\fP is the handle of the stream on which this push arrives. The new
+handle has been duphandle()d from the parent, meaning that it has gotten all
+its options inherited. It is then up to the application to alter any options
+if desired.
+
+\fIeasy\fP is a newly created handle that represents this upcoming transfer.
+
+\fInum_headers\fP is the number of name+value pairs that was received and can
+be accessed
+
+\fIheaders\fP is a handle used to access push headers using the accessor
+functions described below. This only accesses and provides the PUSH_PROMISE
+headers, the normal response headers will be provided in the header callback
+as usual.
+
+\fIuserp\fP is the pointer set with \fICURLMOPT_PUSHDATA(3)\fP
+
+If the callback returns CURL_PUSH_OK, the 'easy' handle will be added to the
+multi handle, the callback must not do that by itself.
+
+The callback can access PUSH_PROMISE headers with two accessor
+functions. These functions can only be used from within this callback and they
+can only access the PUSH_PROMISE headers. The normal response headers will be
+pased to the header callback for pushed streams just as for normal streams.
+.IP curl_pushheader_bynum
+Returns the header at index 'num' (or NULL). The returned pointer points to a
+"name:value" string that will be freed when this callback returns.
+.IP curl_pushheader_byname
+Returns the value for the given header name (or NULL). This is a shortcut so
+that the application doesn't have to loop through all headers to find the one
+it is interested in. The data pointed will be freed when this callback
+returns.
+.SH CALLBACK RETURN VALUE
+.IP "CURL_PUSH_OK (0)"
+The application has accepted the stream and it can now start receiving data,
+the ownership of the CURL handle has been taken over by the application.
+.IP "CURL_PUSH_DENY (1)"
+The callback denies the stream and no data for this will reach the
+application, the easy handle will be destroyed by libcurl.
+.IP *
+All other return codes are reserved for future use.
+.SH DEFAULT
+NULL, no callback
+.SH PROTOCOLS
+HTTP(S) (HTTP/2 only)
+.SH EXAMPLE
+.nf
+/* only allow pushes for file names starting with "push-" */
+int push_callback(CURL *parent,
+                  CURL *easy,
+                  size_t num_headers,
+                  struct curl_pushheaders *headers,
+                  void *userp)
+{
+  char *headp;
+  int *transfers = (int *)userp;
+  FILE *out;
+  headp = curl_pushheader_byname(headers, ":path");
+  if(headp && !strncmp(headp, "/push-", 6)) {
+    fprintf(stderr, "The PATH is %s\n", headp);
+
+    /* save the push here */
+    out = fopen("pushed-stream", "wb");
+
+    /* write to this file */
+    curl_easy_setopt(easy, CURLOPT_WRITEDATA, out);
+
+    (*transfers)++; /* one more */
+
+    return CURL_PUSH_OK;
+  }
+  return CURL_PUSH_DENY;
+}
+
+curl_multi_setopt(multi, CURLMOPT_PUSHFUNCTION, push_callback);
+curl_multi_setopt(multi, CURLMOPT_PUSHDATA, &counter);
+.fi
+.SH AVAILABILITY
+Added in 7.44.0
+.SH RETURN VALUE
+Returns CURLM_OK if the option is supported, and CURLM_UNKNOWN_OPTION if not.
+.SH "SEE ALSO"
+.BR CURLMOPT_PUSHDATA "(3), " CURLMOPT_PIPELINING "(3), " CURLOPT_PIPEWAIT "(3), "
+.BR RFC 7540

docs/libcurl/opts/Makefile.am

@@ -114,7 +114,8 @@ man_MANS = CURLOPT_ACCEPT_ENCODING.3 CURLOPT_ACCEPTTIMEOUT_MS.3		\
  CURLMOPT_SOCKETDATA.3 CURLMOPT_SOCKETFUNCTION.3 CURLMOPT_TIMERDATA.3	\
  CURLMOPT_TIMERFUNCTION.3 CURLOPT_UNIX_SOCKET_PATH.3			\
  CURLOPT_PATH_AS_IS.3 CURLOPT_PROXY_SERVICE_NAME.3			\
- CURLOPT_SERVICE_NAME.3 CURLOPT_PIPEWAIT.3
+ CURLOPT_SERVICE_NAME.3 CURLOPT_PIPEWAIT.3 CURLMOPT_PUSHDATA.3		\
+ CURLMOPT_PUSHFUNCTION.3
 
 HTMLPAGES = CURLOPT_ACCEPT_ENCODING.html CURLOPT_ACCEPTTIMEOUT_MS.html	\
  CURLOPT_ADDRESS_SCOPE.html CURLOPT_APPEND.html				\
@@ -222,7 +223,8 @@ HTMLPAGES = CURLOPT_ACCEPT_ENCODING.html CURLOPT_ACCEPTTIMEOUT_MS.html	\
  CURLMOPT_TIMERDATA.html CURLMOPT_TIMERFUNCTION.html			\
  CURLOPT_UNIX_SOCKET_PATH.html CURLOPT_PATH_AS_IS.html			\
  CURLOPT_PROXY_SERVICE_NAME.html CURLOPT_SERVICE_NAME.html		\
- CURLOPT_PIPEWAIT.html
+ CURLOPT_PIPEWAIT.html CURLMOPT_PUSHDATA.html				\
+ CURLMOPT_PUSHFUNCTION.html
 
 PDFPAGES = CURLOPT_ACCEPT_ENCODING.pdf CURLOPT_ACCEPTTIMEOUT_MS.pdf	\
  CURLOPT_ADDRESS_SCOPE.pdf CURLOPT_APPEND.pdf CURLOPT_AUTOREFERER.pdf	\
@@ -328,7 +330,7 @@ PDFPAGES = CURLOPT_ACCEPT_ENCODING.pdf CURLOPT_ACCEPTTIMEOUT_MS.pdf	\
  CURLMOPT_TIMERDATA.pdf CURLMOPT_TIMERFUNCTION.pdf			\
  CURLOPT_UNIX_SOCKET_PATH.pdf CURLOPT_PATH_AS_IS.pdf			\
  CURLOPT_PROXY_SERVICE_NAME.pdf CURLOPT_SERVICE_NAME.pdf		\
- CURLOPT_PIPEWAIT.pdf
+ CURLOPT_PIPEWAIT.pdf CURLMOPT_PUSHDATA.pdf CURLMOPT_PUSHFUNCTION.pdf
 
 CLEANFILES = $(HTMLPAGES) $(PDFPAGES)
 

include/curl/multi.h

@@ -283,6 +283,30 @@ typedef int (*curl_multi_timer_callback)(CURLM *multi,    /* multi handle */
                                          void *userp);    /* private callback
                                                              pointer */
 
+/*
+ * Name: curl_push_callback
+ *
+ * Desc: This callback gets called when a new stream is being pushed by the
+ *       server. It approves or denies the new stream.
+ *
+ * Returns: CURL_PUSH_OK or CURL_PUSH_DENY.
+ */
+#define CURL_PUSH_OK   0
+#define CURL_PUSH_DENY 1
+
+struct curl_pushheaders;  /* forward declaration only */
+
+CURL_EXTERN char *curl_pushheader_bynum(struct curl_pushheaders *h,
+                                        size_t num);
+CURL_EXTERN char *curl_pushheader_byname(struct curl_pushheaders *h,
+                                         const char *name);
+
+typedef int (*curl_push_callback)(CURL *parent,
+                                  CURL *easy,
+                                  size_t num_headers,
+                                  struct curl_pushheaders *headers,
+                                  void *userp);
+
 CURL_EXTERN CURLMcode curl_multi_socket(CURLM *multi_handle, curl_socket_t s,
                                         int *running_handles);
 
@@ -370,6 +394,12 @@ typedef enum {
   /* maximum number of open connections in total */
   CINIT(MAX_TOTAL_CONNECTIONS, LONG, 13),
 
+   /* This is the server push callback function pointer */
+  CINIT(PUSHFUNCTION, FUNCTIONPOINT, 14),
+
+  /* This is the argument passed to the server push callback */
+  CINIT(PUSHDATA, OBJECTPOINT, 15),
+
   CURLMOPT_LASTENTRY /* the last unused */
 } CURLMoption;
 

lib/http.c

@@ -164,6 +164,7 @@ CURLcode Curl_http_setup_conn(struct connectdata *conn)
   conn->data->req.protop = http;
 
   Curl_http2_setup_conn(conn);
+  Curl_http2_setup_req(conn->data);
 
   return CURLE_OK;
 }
@@ -175,6 +176,8 @@ static CURLcode http_disconnect(struct connectdata *conn, bool dead_connection)
   if(http) {
     Curl_add_buffer_free(http->header_recvbuf);
     http->header_recvbuf = NULL; /* clear the pointer */
+    free(http->push_headers);
+    http->push_headers = NULL;
   }
 #else
   (void)conn;
@@ -1491,6 +1494,8 @@ CURLcode Curl_http_done(struct connectdata *conn,
     DEBUGF(infof(data, "free header_recvbuf!!\n"));
     Curl_add_buffer_free(http->header_recvbuf);
     http->header_recvbuf = NULL; /* clear the pointer */
+    free(http->push_headers);
+    http->push_headers = NULL;
   }
 #endif
 

lib/http.h

@@ -176,6 +176,10 @@ struct HTTP {
   const uint8_t *upload_mem; /* points to a buffer to read from */
   size_t upload_len; /* size of the buffer 'upload_mem' points to */
   curl_off_t upload_left; /* number of bytes left to upload */
+
+  char **push_headers;       /* allocated array */
+  size_t push_headers_used;  /* number of entries filled in */
+  size_t push_headers_alloc; /* number of entries allocated */
 #endif
 };
 

lib/http2.c

@@ -33,6 +33,7 @@
 #include "rawstr.h"
 #include "multiif.h"
 #include "conncache.h"
+#include "url.h"
 
 /* The last #include files should be: */
 #include "curl_memory.h"
@@ -94,12 +95,9 @@ static CURLcode http2_disconnect(struct connectdata *conn,
 }
 
 /* called from Curl_http_setup_conn */
-void Curl_http2_setup_conn(struct connectdata *conn)
+void Curl_http2_setup_req(struct SessionHandle *data)
 {
-  struct HTTP *http = conn->data->req.protop;
-
-  conn->proto.httpc.settings.max_concurrent_streams =
-    DEFAULT_MAX_CONCURRENT_STREAMS;
+  struct HTTP *http = data->req.protop;
 
   http->nread_header_recvbuf = 0;
   http->bodystarted = FALSE;
@@ -108,13 +106,18 @@ void Curl_http2_setup_conn(struct connectdata *conn)
   http->pauselen = 0;
   http->error_code = NGHTTP2_NO_ERROR;
   http->closed = FALSE;
-
-  /* where to store incoming data for this stream and how big the buffer is */
-  http->mem = conn->data->state.buffer;
+  http->mem = data->state.buffer;
   http->len = BUFSIZE;
   http->memlen = 0;
 }
 
+/* called from Curl_http_setup_conn */
+void Curl_http2_setup_conn(struct connectdata *conn)
+{
+  conn->proto.httpc.settings.max_concurrent_streams =
+    DEFAULT_MAX_CONCURRENT_STREAMS;
+}
+
 /*
  * HTTP2 handler interface. This isn't added to the general list of protocols
  * but will be used at run-time when the protocol is dynamically switched from
@@ -205,6 +208,160 @@ static ssize_t send_callback(nghttp2_session *h2,
   return written;
 }
 
+
+/* We pass a pointer to this struct in the push callback, but the contents of
+   the struct are hidden from the user. */
+struct curl_pushheaders {
+  struct SessionHandle *data;
+  const nghttp2_push_promise *frame;
+};
+
+/*
+ * push header access function. Only to be used from within the push callback
+ */
+char *curl_pushheader_bynum(struct curl_pushheaders *h, size_t num)
+{
+  /* Verify that we got a good easy handle in the push header struct, mostly to
+     detect rubbish input fast(er). */
+  if(!h || !GOOD_EASY_HANDLE(h->data))
+    return NULL;
+  else {
+    struct HTTP *stream = h->data->req.protop;
+    if(num < stream->push_headers_used)
+      return stream->push_headers[num];
+  }
+  return NULL;
+}
+
+/*
+ * push header access function. Only to be used from within the push callback
+ */
+char *curl_pushheader_byname(struct curl_pushheaders *h, const char *header)
+{
+  /* Verify that we got a good easy handle in the push header struct,
+     mostly to detect rubbish input fast(er). Also empty header name
+     is just a rubbish too. We have to allow ":" at the beginning of
+     the header, but header == ":" must be rejected. If we have ':' in
+     the middle of header, it could be matched in middle of the value,
+     this is because we do prefix match.*/
+  if(!h || !GOOD_EASY_HANDLE(h->data) || !header || !header[0] ||
+     Curl_raw_equal(header, ":") || strchr(header + 1, ':'))
+    return NULL;
+  else {
+    struct HTTP *stream = h->data->req.protop;
+    size_t len = strlen(header);
+    size_t i;
+    for(i=0; i<stream->push_headers_used; i++) {
+      if(!strncmp(header, stream->push_headers[i], len)) {
+        /* sub-match, make sure that it us followed by a colon */
+        if(stream->push_headers[i][len] != ':')
+          continue;
+        return &stream->push_headers[i][len+1];
+      }
+    }
+  }
+  return NULL;
+}
+
+static CURL *duphandle(struct SessionHandle *data)
+{
+  struct SessionHandle *second = curl_easy_duphandle(data);
+  if(second) {
+    /* setup the request struct */
+    struct HTTP *http = calloc(1, sizeof(struct HTTP));
+    if(!http) {
+      (void)Curl_close(second);
+      second = NULL;
+    }
+    else {
+      second->req.protop = http;
+      http->header_recvbuf = Curl_add_buffer_init();
+      if(!http->header_recvbuf) {
+        free(http);
+        (void)Curl_close(second);
+        second = NULL;
+      }
+      else
+        Curl_http2_setup_req(second);
+    }
+  }
+  return second;
+}
+
+
+static int push_promise(struct SessionHandle *data,
+                        struct connectdata *conn,
+                        const nghttp2_push_promise *frame)
+{
+  int rv;
+  DEBUGF(infof(data, "PUSH_PROMISE received, stream %u!\n",
+               frame->promised_stream_id));
+  if(data->multi->push_cb) {
+    struct HTTP *stream;
+    struct curl_pushheaders heads;
+    CURLMcode rc;
+    struct http_conn *httpc;
+    size_t i;
+    /* clone the parent */
+    CURL *newhandle = duphandle(data);
+    if(!newhandle) {
+      infof(data, "failed to duplicate handle\n");
+      rv = 1; /* FAIL HARD */
+      goto fail;
+    }
+
+    heads.data = data;
+    heads.frame = frame;
+    /* ask the application */
+    DEBUGF(infof(data, "Got PUSH_PROMISE, ask application!\n"));
+
+    stream = data->req.protop;
+
+    rv = data->multi->push_cb(data, newhandle,
+                              stream->push_headers_used, &heads,
+                              data->multi->push_userp);
+
+    /* free the headers again */
+    for(i=0; i<stream->push_headers_used; i++)
+      free(stream->push_headers[i]);
+    free(stream->push_headers);
+    stream->push_headers = NULL;
+
+    if(rv) {
+      /* denied, kill off the new handle again */
+      (void)Curl_close(newhandle);
+      goto fail;
+    }
+
+    /* approved, add to the multi handle and immediately switch to PERFORM
+       state with the given connection !*/
+    rc = Curl_multi_add_perform(data->multi, newhandle, conn);
+    if(rc) {
+      infof(data, "failed to add handle to multi\n");
+      Curl_close(newhandle);
+      rv = 1;
+      goto fail;
+    }
+
+    httpc = &conn->proto.httpc;
+    /* put the newhandle in the hash with the stream id as key */
+    if(!Curl_hash_add(&httpc->streamsh,
+                      (size_t *)&frame->promised_stream_id,
+                      sizeof(frame->promised_stream_id), newhandle)) {
+      failf(conn->data, "Couldn't add stream to hash!");
+      rv = 1;
+    }
+    else
+      rv = 0;
+  }
+  else {
+    DEBUGF(infof(data, "Got PUSH_PROMISE, ignore it!\n"));
+    rv = 1;
+  }
+  fail:
+  return rv;
+}
+
 static int on_frame_recv(nghttp2_session *session, const nghttp2_frame *frame,
                          void *userp)
 {
@@ -292,12 +449,14 @@ static int on_frame_recv(nghttp2_session *session, const nghttp2_frame *frame,
     Curl_expire(data_s, 1);
     break;
   case NGHTTP2_PUSH_PROMISE:
-    DEBUGF(infof(data_s, "Got PUSH_PROMISE, RST_STREAM it!\n"));
-    rv = nghttp2_submit_rst_stream(session, NGHTTP2_FLAG_NONE,
-                                   frame->push_promise.promised_stream_id,
-                                   NGHTTP2_CANCEL);
-    if(nghttp2_is_fatal(rv)) {
-      return rv;
+    rv = push_promise(data_s, conn, &frame->push_promise);
+    if(rv) { /* deny! */
+      rv = nghttp2_submit_rst_stream(session, NGHTTP2_FLAG_NONE,
+                                     frame->push_promise.promised_stream_id,
+                                     NGHTTP2_CANCEL);
+      if(nghttp2_is_fatal(rv)) {
+        return rv;
+      }
     }
     break;
   case NGHTTP2_SETTINGS:
@@ -523,11 +682,6 @@ static int on_header(nghttp2_session *session, const nghttp2_frame *frame,
   (void)frame;
   (void)flags;
 
-  /* Ignore PUSH_PROMISE for now */
-  if(frame->hd.type != NGHTTP2_HEADERS) {
-    return 0;
-  }
-
   DEBUGASSERT(stream_id); /* should never be a zero stream ID here */
 
   /* get the stream from the hash based on Stream ID */
@@ -547,6 +701,36 @@ static int on_header(nghttp2_session *session, const nghttp2_frame *frame,
        consequence is handled in on_frame_recv(). */
     return 0;
 
+  /* Store received PUSH_PROMISE headers to be used when the subsequent
+     PUSH_PROMISE callback comes */
+  if(frame->hd.type == NGHTTP2_PUSH_PROMISE) {
+    char *h;
+
+    if(!stream->push_headers) {
+      stream->push_headers_alloc = 10;
+      stream->push_headers = malloc(stream->push_headers_alloc *
+                                    sizeof(char *));
+      stream->push_headers_used = 0;
+    }
+    else if(stream->push_headers_used ==
+            stream->push_headers_alloc) {
+      char **headp;
+      stream->push_headers_alloc *= 2;
+      headp = realloc(stream->push_headers,
+                      stream->push_headers_alloc * sizeof(char *));
+      if(!headp) {
+        free(stream->push_headers);
+        stream->push_headers = NULL;
+        return NGHTTP2_ERR_TEMPORAL_CALLBACK_FAILURE;
+      }
+      stream->push_headers = headp;
+    }
+    h = aprintf("%s:%s", name, value);
+    if(h)
+      stream->push_headers[stream->push_headers_used++] = h;
+    return 0;
+  }
+
   if(namelen == sizeof(":status") - 1 &&
      memcmp(":status", name, namelen) == 0) {
     /* nghttp2 guarantees :status is received first and only once, and

lib/http2.h

@@ -46,6 +46,7 @@ CURLcode Curl_http2_switched(struct connectdata *conn,
                              const char *data, size_t nread);
 /* called from Curl_http_setup_conn */
 void Curl_http2_setup_conn(struct connectdata *conn);
+void Curl_http2_setup_req(struct SessionHandle *data);
 #else /* USE_NGHTTP2 */
 #define Curl_http2_init(x) CURLE_UNSUPPORTED_PROTOCOL
 #define Curl_http2_send_request(x) CURLE_UNSUPPORTED_PROTOCOL
@@ -53,6 +54,7 @@ void Curl_http2_setup_conn(struct connectdata *conn);
 #define Curl_http2_setup(x) CURLE_UNSUPPORTED_PROTOCOL
 #define Curl_http2_switched(x,y,z) CURLE_UNSUPPORTED_PROTOCOL
 #define Curl_http2_setup_conn(x)
+#define Curl_http2_setup_req(x)
 #endif
 
 #endif /* HEADER_CURL_HTTP2_H */

lib/multi.c

@@ -62,8 +62,6 @@
 
 #define GOOD_MULTI_HANDLE(x) \
   ((x) && (((struct Curl_multi *)(x))->type == CURL_MULTI_HANDLE))
-#define GOOD_EASY_HANDLE(x) \
-  ((x) && (((struct SessionHandle *)(x))->magic == CURLEASY_MAGIC_NUMBER))
 
 static void singlesocket(struct Curl_multi *multi,
                          struct SessionHandle *data);
@@ -957,6 +955,28 @@ static bool multi_ischanged(struct Curl_multi *multi, bool clear)
   return retval;
 }
 
+CURLMcode Curl_multi_add_perform(struct Curl_multi *multi,
+                                 struct SessionHandle *data,
+                                 struct connectdata *conn)
+{
+  CURLMcode rc;
+
+  rc = curl_multi_add_handle(multi, data);
+  if(!rc) {
+    struct SingleRequest *k = &data->req;
+
+    /* pass in NULL for 'conn' here since we don't want to init the
+       connection, only this transfer */
+    Curl_init_do(data, NULL);
+
+    /* take this handle to the perform state right away */
+    multistate(data, CURLM_STATE_PERFORM);
+    data->easy_conn = conn;
+    k->keepon |= KEEP_RECV; /* setup to receive! */
+  }
+  return rc;
+}
+
 static CURLMcode multi_runsingle(struct Curl_multi *multi,
                                  struct timeval now,
                                  struct SessionHandle *data)
@@ -2346,6 +2366,12 @@ CURLMcode curl_multi_setopt(CURLM *multi_handle,
   case CURLMOPT_SOCKETDATA:
     multi->socket_userp = va_arg(param, void *);
     break;
+  case CURLMOPT_PUSHFUNCTION:
+    multi->push_cb = va_arg(param, curl_push_callback);
+    break;
+  case CURLMOPT_PUSHDATA:
+    multi->push_userp = va_arg(param, void *);
+    break;
   case CURLMOPT_PIPELINING:
     multi->pipelining = va_arg(param, long);
     break;

lib/multihandle.h

@@ -87,6 +87,10 @@ struct Curl_multi {
   curl_socket_callback socket_cb;
   void *socket_userp;
 
+  /* callback function and user data pointer for server push */
+  curl_push_callback push_cb;
+  void *push_userp;
+
   /* Hostname cache */
   struct curl_hash hostcache;
 

lib/multiif.h

@@ -88,4 +88,10 @@ void Curl_multi_connchanged(struct Curl_multi *multi);
 
 void Curl_multi_closed(struct connectdata *conn, curl_socket_t s);
 
+/*
+ * Add a handle and move it into PERFORM state at once. For pushed streams.
+ */
+CURLMcode Curl_multi_add_perform(struct Curl_multi *multi,
+                                 struct SessionHandle *data,
+                                 struct connectdata *conn);
 #endif /* HEADER_CURL_MULTIIF_H */

lib/url.c

@@ -142,7 +142,6 @@ find_oldest_idle_connection_in_bundle(struct SessionHandle *data,
                                       struct connectbundle *bundle);
 static void conn_free(struct connectdata *conn);
 static void signalPipeClose(struct curl_llist *pipeline, bool pipe_broke);
-static CURLcode do_init(struct connectdata *conn);
 static CURLcode parse_url_login(struct SessionHandle *data,
                                 struct connectdata *conn,
                                 char **userptr, char **passwdptr,
@@ -5651,7 +5650,7 @@ static CURLcode create_conn(struct SessionHandle *data,
     }
 
     /* since we skip do_init() */
-    do_init(conn);
+    Curl_init_do(data, conn);
 
     goto out;
   }
@@ -5830,7 +5829,7 @@ static CURLcode create_conn(struct SessionHandle *data,
   conn->inuse = TRUE;
 
   /* Setup and init stuff before DO starts, in preparing for the transfer. */
-  do_init(conn);
+  Curl_init_do(data, conn);
 
   /*
    * Setup whatever necessary for a resumed transfer
@@ -6112,20 +6111,24 @@ CURLcode Curl_done(struct connectdata **connp,
 }
 
 /*
- * do_init() inits the readwrite session. This is inited each time (in the DO
- * function before the protocol-specific DO functions are invoked) for a
- * transfer, sometimes multiple times on the same SessionHandle. Make sure
+ * Curl_init_do() inits the readwrite session. This is inited each time (in
+ * the DO function before the protocol-specific DO functions are invoked) for
+ * a transfer, sometimes multiple times on the same SessionHandle. Make sure
  * nothing in here depends on stuff that are setup dynamically for the
  * transfer.
+ *
+ * Allow this function to get called with 'conn' set to NULL.
  */
 
-static CURLcode do_init(struct connectdata *conn)
+CURLcode Curl_init_do(struct SessionHandle *data, struct connectdata *conn)
 {
-  struct SessionHandle *data = conn->data;
   struct SingleRequest *k = &data->req;
 
+  if(conn)
+    conn->bits.do_more = FALSE; /* by default there's no curl_do_more() to
+                                 * use */
+
   data->state.done = FALSE; /* Curl_done() is not called yet */
-  conn->bits.do_more = FALSE; /* by default there's no curl_do_more() to use */
   data->state.expect100header = FALSE;
 
   if(data->set.opt_no_body)

lib/url.h

@@ -7,7 +7,7 @@
  *                            | (__| |_| |  _ <| |___
  *                             \___|\___/|_| \_\_____|
  *
- * Copyright (C) 1998 - 2013, Daniel Stenberg, <daniel@haxx.se>, et al.
+ * Copyright (C) 1998 - 2015, Daniel Stenberg, <daniel@haxx.se>, et al.
  *
  * This software is licensed as described in the file COPYING, which
  * you should have received as part of this distribution. The terms
@@ -27,6 +27,7 @@
  * Prototypes for library-wide functions provided by url.c
  */
 
+CURLcode Curl_init_do(struct SessionHandle *data, struct connectdata *conn);
 CURLcode Curl_open(struct SessionHandle **curl);
 CURLcode Curl_init_userdefined(struct UserDefined *set);
 CURLcode Curl_setopt(struct SessionHandle *data, CURLoption option,

lib/urldata.h

@@ -198,6 +198,8 @@
 #define HEADERSIZE 256
 
 #define CURLEASY_MAGIC_NUMBER 0xc0dedbadU
+#define GOOD_EASY_HANDLE(x) \
+  ((x) && (((struct SessionHandle *)(x))->magic == CURLEASY_MAGIC_NUMBER))
 
 /* Some convenience macros to get the larger/smaller value out of two given.
    We prefix with CURL to prevent name collisions. */