CURLOPT_PROXYHEADER: set headers for proxy-only

Includes docs and new test cases: 1525, 1526 and 1527

Co-written-by: Vijay Panghal

6 files changed, 97 insertions, 45 deletions

diff --git a/lib/http.c b/lib/http.c
index f803e58f8..c0cb4c069 100644
--- a/lib/http.c
+++ b/lib/http.c
@@ -169,12 +169,40 @@ CURLcode Curl_http_setup_conn(struct connectdata *conn)
  *
  * Returns a pointer to the first matching header or NULL if none matched.
  */
-char *Curl_checkheaders(struct SessionHandle *data, const char *thisheader)
+char *Curl_checkheaders(const struct connectdata *conn,
+                        const char *thisheader)
 {
   struct curl_slist *head;
   size_t thislen = strlen(thisheader);
+  struct SessionHandle *data = conn->data;
+
+  for(head = data->set.headers;head; head=head->next) {
+    if(Curl_raw_nequal(head->data, thisheader, thislen))
+      return head->data;
+  }
+  return NULL;
+}
+
+/*
+ * checkProxyHeaders() checks the linked list of custom proxy headers
+ * if proxy headers are not available, then it will lookup into http header
+ * link list
+ *
+ * It takes a connectdata struct as input instead of the SessionHandle simply
+ * to know if this is a proxy request or not, as it then might check a
+ * different header list.
+ *
+ */
+char *Curl_checkProxyheaders(const struct connectdata *conn,
+                             const char *thisheader)
+{
+  struct curl_slist *head;
+  size_t thislen = strlen(thisheader);
+  struct SessionHandle *data = conn->data;
 
-  for(head = data->set.headers; head; head=head->next) {
+  for(head = (conn->bits.proxy && data->set.proxyheaders)?
+        data->set.proxyheaders:data->set.headers;
+      head; head=head->next) {
     if(Curl_raw_nequal(head->data, thisheader, thislen))
       return head->data;
   }
@@ -584,9 +612,9 @@ output_auth_headers(struct connectdata *conn,
   if(authstatus->picked == CURLAUTH_BASIC) {
     /* Basic */
     if((proxy && conn->bits.proxy_user_passwd &&
-       !Curl_checkheaders(data, "Proxy-authorization:")) ||
+        !Curl_checkProxyheaders(conn, "Proxy-authorization:")) ||
        (!proxy && conn->bits.user_passwd &&
-       !Curl_checkheaders(data, "Authorization:"))) {
+        !Curl_checkheaders(conn, "Authorization:"))) {
       auth="Basic";
       result = http_output_basic(conn, proxy);
       if(result)
@@ -1501,7 +1529,7 @@ static CURLcode expect100(struct SessionHandle *data,
     /* if not doing HTTP 1.0 or disabled explicitly, we add a Expect:
        100-continue to the headers which actually speeds up post operations
        (as there is one packet coming back from the web server) */
-    ptr = Curl_checkheaders(data, "Expect:");
+    ptr = Curl_checkheaders(conn, "Expect:");
     if(ptr) {
       data->state.expect100header =
         Curl_compareheader(ptr, "Expect:", "100-continue");
@@ -1517,10 +1545,13 @@ static CURLcode expect100(struct SessionHandle *data,
 }
 
 CURLcode Curl_add_custom_headers(struct connectdata *conn,
-                                   Curl_send_buffer *req_buffer)
+                                 bool is_proxy,
+                                 Curl_send_buffer *req_buffer)
 {
   char *ptr;
-  struct curl_slist *headers=conn->data->set.headers;
+  struct curl_slist *headers=
+    (is_proxy && conn->data->set.proxyheaders)?
+    conn->data->set.proxyheaders:conn->data->set.headers;
 
   while(headers) {
     ptr = strchr(headers->data, ':');
@@ -1736,7 +1767,7 @@ CURLcode Curl_http(struct connectdata *conn, bool *done)
      it might have been used in the proxy connect, but if we have got a header
      with the user-agent string specified, we erase the previously made string
      here. */
-  if(Curl_checkheaders(data, "User-Agent:") && conn->allocptr.uagent) {
+  if(Curl_checkheaders(conn, "User-Agent:") && conn->allocptr.uagent) {
     free(conn->allocptr.uagent);
     conn->allocptr.uagent=NULL;
   }
@@ -1757,7 +1788,7 @@ CURLcode Curl_http(struct connectdata *conn, bool *done)
     conn->bits.authneg = FALSE;
 
   Curl_safefree(conn->allocptr.ref);
-  if(data->change.referer && !Curl_checkheaders(data, "Referer:")) {
+  if(data->change.referer && !Curl_checkheaders(conn, "Referer:")) {
     conn->allocptr.ref = aprintf("Referer: %s\r\n", data->change.referer);
     if(!conn->allocptr.ref)
       return CURLE_OUT_OF_MEMORY;
@@ -1765,10 +1796,10 @@ CURLcode Curl_http(struct connectdata *conn, bool *done)
   else
     conn->allocptr.ref = NULL;
 
-  if(data->set.str[STRING_COOKIE] && !Curl_checkheaders(data, "Cookie:"))
+  if(data->set.str[STRING_COOKIE] && !Curl_checkheaders(conn, "Cookie:"))
     addcookies = data->set.str[STRING_COOKIE];
 
-  if(!Curl_checkheaders(data, "Accept-Encoding:") &&
+  if(!Curl_checkheaders(conn, "Accept-Encoding:") &&
      data->set.str[STRING_ENCODING]) {
     Curl_safefree(conn->allocptr.accept_encoding);
     conn->allocptr.accept_encoding =
@@ -1780,13 +1811,14 @@ CURLcode Curl_http(struct connectdata *conn, bool *done)
 #ifdef HAVE_LIBZ
   /* we only consider transfer-encoding magic if libz support is built-in */
 
-  if(!Curl_checkheaders(data, "TE:") && data->set.http_transfer_encoding) {
+  if(!Curl_checkheaders(conn, "TE:") &&
+     data->set.http_transfer_encoding) {
     /* When we are to insert a TE: header in the request, we must also insert
        TE in a Connection: header, so we need to merge the custom provided
        Connection: header and prevent the original to get sent. Note that if
        the user has inserted his/hers own TE: header we don't do this magic
        but then assume that the user will handle it all! */
-    char *cptr = Curl_checkheaders(data, "Connection:");
+    char *cptr = Curl_checkheaders(conn, "Connection:");
 #define TE_HEADER "TE: gzip\r\n"
 
     Curl_safefree(conn->allocptr.te);
@@ -1804,7 +1836,7 @@ CURLcode Curl_http(struct connectdata *conn, bool *done)
     /* In HTTP2 forbids Transfer-Encoding: chunked */
     ptr = NULL;
   else {
-    ptr = Curl_checkheaders(data, "Transfer-Encoding:");
+    ptr = Curl_checkheaders(conn, "Transfer-Encoding:");
     if(ptr) {
       /* Some kind of TE is requested, check if 'chunked' is chosen */
       data->req.upload_chunky =
@@ -1838,7 +1870,7 @@ CURLcode Curl_http(struct connectdata *conn, bool *done)
 
   Curl_safefree(conn->allocptr.host);
 
-  ptr = Curl_checkheaders(data, "Host:");
+  ptr = Curl_checkheaders(conn, "Host:");
   if(ptr && (!data->state.this_is_a_follow ||
              Curl_raw_equal(data->state.first_host, conn->host.name))) {
 #if !defined(CURL_DISABLE_COOKIES)
@@ -1983,13 +2015,13 @@ CURLcode Curl_http(struct connectdata *conn, bool *done)
     /* we must build the whole post sequence first, so that we have a size of
        the whole transfer before we start to send it */
     result = Curl_getformdata(data, &http->sendit, data->set.httppost,
-                              Curl_checkheaders(data, "Content-Type:"),
+                              Curl_checkheaders(conn, "Content-Type:"),
                               &http->postsize);
     if(result)
       return result;
   }
 
-  http->p_accept = Curl_checkheaders(data, "Accept:")?NULL:"Accept: */*\r\n";
+  http->p_accept = Curl_checkheaders(conn, "Accept:")?NULL:"Accept: */*\r\n";
 
   if(( (HTTPREQ_POST == httpreq) ||
        (HTTPREQ_POST_FORM == httpreq) ||
@@ -2069,7 +2101,7 @@ CURLcode Curl_http(struct connectdata *conn, bool *done)
      * ones if any such are specified.
      */
     if(((httpreq == HTTPREQ_GET) || (httpreq == HTTPREQ_HEAD)) &&
-       !Curl_checkheaders(data, "Range:")) {
+       !Curl_checkheaders(conn, "Range:")) {
       /* if a line like this was already allocated, free the previous one */
       if(conn->allocptr.rangeline)
         free(conn->allocptr.rangeline);
@@ -2077,7 +2109,7 @@ CURLcode Curl_http(struct connectdata *conn, bool *done)
                                          data->state.range);
     }
     else if((httpreq != HTTPREQ_GET) &&
-            !Curl_checkheaders(data, "Content-Range:")) {
+            !Curl_checkheaders(conn, "Content-Range:")) {
 
       /* if a line like this was already allocated, free the previous one */
       if(conn->allocptr.rangeline)
@@ -2179,7 +2211,7 @@ CURLcode Curl_http(struct connectdata *conn, bool *done)
                      conn->allocptr.ref:"" /* Referer: <data> */,
                      (conn->bits.httpproxy &&
                       !conn->bits.tunnel_proxy &&
-                      !Curl_checkheaders(data, "Proxy-Connection:"))?
+                      !Curl_checkProxyheaders(conn, "Proxy-Connection:"))?
                      "Proxy-Connection: Keep-Alive\r\n":"",
                      te
       );
@@ -2264,7 +2296,7 @@ CURLcode Curl_http(struct connectdata *conn, bool *done)
       return result;
   }
 
-  result = Curl_add_custom_headers(conn, req_buffer);
+  result = Curl_add_custom_headers(conn, FALSE, req_buffer);
   if(result)
     return result;
 
@@ -2314,7 +2346,7 @@ CURLcode Curl_http(struct connectdata *conn, bool *done)
     http->sending = HTTPSEND_BODY;
 
     if(!data->req.upload_chunky &&
-       !Curl_checkheaders(data, "Content-Length:")) {
+       !Curl_checkheaders(conn, "Content-Length:")) {
       /* only add Content-Length if not uploading chunked */
       result = Curl_add_bufferf(req_buffer,
                                 "Content-Length: %" CURL_FORMAT_CURL_OFF_T
@@ -2386,7 +2418,7 @@ CURLcode Curl_http(struct connectdata *conn, bool *done)
       postsize = data->set.infilesize;
 
     if((postsize != -1) && !data->req.upload_chunky &&
-       !Curl_checkheaders(data, "Content-Length:")) {
+       !Curl_checkheaders(conn, "Content-Length:")) {
       /* only add Content-Length if not uploading chunked */
       result = Curl_add_bufferf(req_buffer,
                                 "Content-Length: %" CURL_FORMAT_CURL_OFF_T
@@ -2438,7 +2470,7 @@ CURLcode Curl_http(struct connectdata *conn, bool *done)
        we don't upload data chunked, as RFC2616 forbids us to set both
        kinds of headers (Transfer-Encoding: chunked and Content-Length) */
     if((postsize != -1) && !data->req.upload_chunky &&
-       !Curl_checkheaders(data, "Content-Length:")) {
+       !Curl_checkheaders(conn, "Content-Length:")) {
       /* we allow replacing this header if not during auth negotiation,
          although it isn't very wise to actually set your own */
       result = Curl_add_bufferf(req_buffer,
@@ -2448,7 +2480,7 @@ CURLcode Curl_http(struct connectdata *conn, bool *done)
         return result;
     }
 
-    if(!Curl_checkheaders(data, "Content-Type:")) {
+    if(!Curl_checkheaders(conn, "Content-Type:")) {
       result = Curl_add_bufferf(req_buffer,
                                 "Content-Type: application/"
                                 "x-www-form-urlencoded\r\n");
@@ -2460,7 +2492,7 @@ CURLcode Curl_http(struct connectdata *conn, bool *done)
        the somewhat bigger ones we allow the app to disable it. Just make
        sure that the expect100header is always set to the preferred value
        here. */
-    ptr = Curl_checkheaders(data, "Expect:");
+    ptr = Curl_checkheaders(conn, "Expect:");
     if(ptr) {
       data->state.expect100header =
         Curl_compareheader(ptr, "Expect:", "100-continue");
diff --git a/lib/http.h b/lib/http.h
index 407f7b621..7cf183101 100644
--- a/lib/http.h
+++ b/lib/http.h
@@ -39,9 +39,13 @@ extern const struct Curl_handler Curl_handler_https;
 bool Curl_compareheader(const char *headerline,  /* line to check */
                         const char *header,   /* header keyword _with_ colon */
                         const char *content); /* content string to find */
-char *Curl_checkheaders(struct SessionHandle *data, const char *thisheader);
+
+char *Curl_checkheaders(const struct connectdata *conn,
+                        const char *thisheader);
 char *Curl_copy_header_value(const char *header);
 
+char *Curl_checkProxyheaders(const struct connectdata *conn,
+                             const char *thisheader);
 /* ------------------------------------------------------------------------- */
 /*
  * The add_buffer series of functions are used to build one large memory chunk
@@ -67,7 +71,8 @@ CURLcode Curl_add_buffer_send(Curl_send_buffer *in,
 CURLcode Curl_add_timecondition(struct SessionHandle *data,
                                 Curl_send_buffer *buf);
 CURLcode Curl_add_custom_headers(struct connectdata *conn,
-                                   Curl_send_buffer *req_buffer);
+                                 bool is_connect,
+                                 Curl_send_buffer *req_buffer);
 
 /* protocol-specific functions set up to be called by the main engine */
 CURLcode Curl_http(struct connectdata *conn, bool *done);
diff --git a/lib/http_proxy.c b/lib/http_proxy.c
index adcfe42dd..0ee1a73d5 100644
--- a/lib/http_proxy.c
+++ b/lib/http_proxy.c
@@ -165,7 +165,7 @@ CURLcode Curl_proxyCONNECT(struct connectdata *conn,
           return CURLE_OUT_OF_MEMORY;
         }
 
-        if(!Curl_checkheaders(data, "Host:")) {
+        if(!Curl_checkProxyheaders(conn, "Host:")) {
           host = aprintf("Host: %s\r\n", hostheader);
           if(!host) {
             free(hostheader);
@@ -173,10 +173,10 @@ CURLcode Curl_proxyCONNECT(struct connectdata *conn,
             return CURLE_OUT_OF_MEMORY;
           }
         }
-        if(!Curl_checkheaders(data, "Proxy-Connection:"))
+        if(!Curl_checkProxyheaders(conn, "Proxy-Connection:"))
           proxyconn = "Proxy-Connection: Keep-Alive\r\n";
 
-        if(!Curl_checkheaders(data, "User-Agent:") &&
+        if(!Curl_checkProxyheaders(conn, "User-Agent:") &&
            data->set.str[STRING_USERAGENT])
           useragent = conn->allocptr.uagent;
 
@@ -200,7 +200,7 @@ CURLcode Curl_proxyCONNECT(struct connectdata *conn,
         free(hostheader);
 
         if(CURLE_OK == result)
-          result = Curl_add_custom_headers(conn, req_buffer);
+          result = Curl_add_custom_headers(conn, TRUE, req_buffer);
 
         if(CURLE_OK == result)
           /* CRLF terminate the request */
diff --git a/lib/rtsp.c b/lib/rtsp.c
index 5cd6cb467..e746fb1b1 100644
--- a/lib/rtsp.c
+++ b/lib/rtsp.c
@@ -341,7 +341,7 @@ static CURLcode rtsp_do(struct connectdata *conn, bool *done)
   }
 
   /* Transport Header for SETUP requests */
-  p_transport = Curl_checkheaders(data, "Transport:");
+  p_transport = Curl_checkheaders(conn, "Transport:");
   if(rtspreq == RTSPREQ_SETUP && !p_transport) {
     /* New Transport: setting? */
     if(data->set.str[STRING_RTSP_TRANSPORT]) {
@@ -365,11 +365,11 @@ static CURLcode rtsp_do(struct connectdata *conn, bool *done)
   /* Accept Headers for DESCRIBE requests */
   if(rtspreq == RTSPREQ_DESCRIBE) {
     /* Accept Header */
-    p_accept = Curl_checkheaders(data, "Accept:")?
+    p_accept = Curl_checkheaders(conn, "Accept:")?
       NULL:"Accept: application/sdp\r\n";
 
     /* Accept-Encoding header */
-    if(!Curl_checkheaders(data, "Accept-Encoding:") &&
+    if(!Curl_checkheaders(conn, "Accept-Encoding:") &&
        data->set.str[STRING_ENCODING]) {
       Curl_safefree(conn->allocptr.accept_encoding);
       conn->allocptr.accept_encoding =
@@ -386,18 +386,18 @@ static CURLcode rtsp_do(struct connectdata *conn, bool *done)
      it might have been used in the proxy connect, but if we have got a header
      with the user-agent string specified, we erase the previously made string
      here. */
-  if(Curl_checkheaders(data, "User-Agent:") && conn->allocptr.uagent) {
+  if(Curl_checkheaders(conn, "User-Agent:") && conn->allocptr.uagent) {
     Curl_safefree(conn->allocptr.uagent);
     conn->allocptr.uagent = NULL;
   }
-  else if(!Curl_checkheaders(data, "User-Agent:") &&
+  else if(!Curl_checkheaders(conn, "User-Agent:") &&
           data->set.str[STRING_USERAGENT]) {
     p_uagent = conn->allocptr.uagent;
   }
 
   /* Referrer */
   Curl_safefree(conn->allocptr.ref);
-  if(data->change.referer && !Curl_checkheaders(data, "Referer:"))
+  if(data->change.referer && !Curl_checkheaders(conn, "Referer:"))
     conn->allocptr.ref = aprintf("Referer: %s\r\n", data->change.referer);
   else
     conn->allocptr.ref = NULL;
@@ -414,7 +414,7 @@ static CURLcode rtsp_do(struct connectdata *conn, bool *done)
      (rtspreq  & (RTSPREQ_PLAY | RTSPREQ_PAUSE | RTSPREQ_RECORD))) {
 
     /* Check to see if there is a range set in the custom headers */
-    if(!Curl_checkheaders(data, "Range:") && data->state.range) {
+    if(!Curl_checkheaders(conn, "Range:") && data->state.range) {
       Curl_safefree(conn->allocptr.rangeline);
       conn->allocptr.rangeline = aprintf("Range: %s\r\n", data->state.range);
       p_range = conn->allocptr.rangeline;
@@ -424,11 +424,11 @@ static CURLcode rtsp_do(struct connectdata *conn, bool *done)
   /*
    * Sanity check the custom headers
    */
-  if(Curl_checkheaders(data, "CSeq:")) {
+  if(Curl_checkheaders(conn, "CSeq:")) {
     failf(data, "CSeq cannot be set as a custom header.");
     return CURLE_RTSP_CSEQ_ERROR;
   }
-  if(Curl_checkheaders(data, "Session:")) {
+  if(Curl_checkheaders(conn, "Session:")) {
     failf(data, "Session ID cannot be set as a custom header.");
     return CURLE_BAD_FUNCTION_ARGUMENT;
   }
@@ -484,7 +484,7 @@ static CURLcode rtsp_do(struct connectdata *conn, bool *done)
       return result;
   }
 
-  result = Curl_add_custom_headers(conn, req_buffer);
+  result = Curl_add_custom_headers(conn, FALSE, req_buffer);
   if(result)
     return result;
 
@@ -507,7 +507,7 @@ static CURLcode rtsp_do(struct connectdata *conn, bool *done)
     if(putsize > 0 || postsize > 0) {
       /* As stated in the http comments, it is probably not wise to
        * actually set a custom Content-Length in the headers */
-      if(!Curl_checkheaders(data, "Content-Length:")) {
+      if(!Curl_checkheaders(conn, "Content-Length:")) {
         result = Curl_add_bufferf(req_buffer,
             "Content-Length: %" CURL_FORMAT_CURL_OFF_T"\r\n",
             (data->set.upload ? putsize : postsize));
@@ -517,7 +517,7 @@ static CURLcode rtsp_do(struct connectdata *conn, bool *done)
 
       if(rtspreq == RTSPREQ_SET_PARAMETER ||
          rtspreq == RTSPREQ_GET_PARAMETER) {
-        if(!Curl_checkheaders(data, "Content-Type:")) {
+        if(!Curl_checkheaders(conn, "Content-Type:")) {
           result = Curl_add_bufferf(req_buffer,
               "Content-Type: text/parameters\r\n");
           if(result)
@@ -526,7 +526,7 @@ static CURLcode rtsp_do(struct connectdata *conn, bool *done)
       }
 
       if(rtspreq == RTSPREQ_ANNOUNCE) {
-        if(!Curl_checkheaders(data, "Content-Type:")) {
+        if(!Curl_checkheaders(conn, "Content-Type:")) {
           result = Curl_add_bufferf(req_buffer,
               "Content-Type: application/sdp\r\n");
           if(result)
diff --git a/lib/url.c b/lib/url.c
index ebd38ccee..25bb04115 100644
--- a/lib/url.c
+++ b/lib/url.c
@@ -1067,6 +1067,20 @@ CURLcode Curl_setopt(struct SessionHandle *data, CURLoption option,
     data->set.headers = va_arg(param, struct curl_slist *);
     break;
 
+  case CURLOPT_PROXYHEADER:
+    /*
+     * Set a list with proxy headers to use (or replace internals with)
+     *
+     * Since CURLOPT_HTTPHEADER was the only way to set HTTP headers for a
+     * long time we remain doing it this way until CURLOPT_PROXYHEADER is
+     * used. As soon as this option has been used, if set to anything but
+     * NULL, custom headers for proxies are only picked from this list.
+     *
+     * Set this option to NULL to restore the previous behavior.
+     */
+    data->set.proxyheaders = va_arg(param, struct curl_slist *);
+    break;
+
   case CURLOPT_HTTP200ALIASES:
     /*
      * Set a list of aliases for HTTP 200 in response header
diff --git a/lib/urldata.h b/lib/urldata.h
index b24562a4d..fd13eb981 100644
--- a/lib/urldata.h
+++ b/lib/urldata.h
@@ -1465,6 +1465,7 @@ struct UserDefined {
                                 download */
   curl_off_t set_resume_from;  /* continue [ftp] transfer from here */
   struct curl_slist *headers; /* linked list of extra headers */
+  struct curl_slist *proxyheaders; /* linked list of extra CONNECT headers */
   struct curl_httppost *httppost;  /* linked list of POST data */
   bool cookiesession;   /* new cookie session? */
   bool crlf;            /* convert crlf on ftp upload(?) */