twister can now modify headers in http responses

7 files changed, 212 insertions, 18 deletions

diff --git a/src/include/taler_twister_service.h b/src/include/taler_twister_service.h
index 13b289d..6583fd9 100644
--- a/src/include/taler_twister_service.h
+++ b/src/include/taler_twister_service.h
@@ -115,6 +115,25 @@ TALER_TWISTER_modify_path_ul (struct TALER_TWISTER_Handle *h,
 
 
 /**
+ * Change the HTTP response header of @a header to @a value.
+ *
+ * @param h twister instance to control
+ * @param header the HTTP response header to modify
+ * @param value value to use for @a header
+ * @param cb callback to call once twister gets this instruction.
+ * @param cb_cls closure for @a cb_callback
+ *
+ * @return operation handle.
+ */
+struct TALER_TWISTER_Operation *
+TALER_TWISTER_modify_header_dl (struct TALER_TWISTER_Handle *h,
+                                const char *header,
+                                const char *value,
+                                GNUNET_SCHEDULER_TaskCallback cb,
+                                void *cb_cls);
+
+
+/**
  * Instruct the twister to flip a character into
  * the string JSON field that belongs to the object
  * being returned to the HTTP client.
diff --git a/src/test/test_twister.sh b/src/test/test_twister.sh
index 0347f66..c6713ce 100755
--- a/src/test/test_twister.sh
+++ b/src/test/test_twister.sh
@@ -2,17 +2,17 @@
 
 # This file is part of GNUnet.
 # Copyright (C) 2018 Taler Systems SA
-# 
+#
 # Twister is free software; you can redistribute it and/or
 # modify it under the terms of the GNU General Public License
 # as published by the Free Software Foundation; either version
 # 3, or (at your option) any later version.
-# 
+#
 # Twister is distributed in the hope that it will be useful,
 # but WITHOUT ANY WARRANTY; without even the implied warranty
 # of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
 # the GNU General Public License for more details.
-# 
+#
 # You should have received a copy of the GNU General Public
 # License along with Twister; see the file COPYING.  If not,
 # write to the Free Software Foundation, Inc., 51 Franklin
@@ -20,9 +20,9 @@
 
 # @author Marcello Stanisci
 # @author Christian Grothoff
-# 
+#
 # @file test_twister.sh
-# 
+#
 # @brief Twister testcases.
 
 
@@ -150,6 +150,24 @@ fi
 
 echo "field-modification with string passed".
 
+# set header
+taler-twister -c ./test_twister.conf \
+  -H "Date" \
+  --value "January 32nd"
+modobject_body=$(curl -sI ${TWISTER_URL} | grep -Fi Date | tr -d '\r')
+echo $modobject_body
+
+if ! test \
+    'Date: January 32nd' = "$modobject_body"; then
+  printf "Response header (%s) has not been modified as expected\n" \
+    "$modobject_body"
+  kill $web_server_pid
+  kill $twister_service_pid
+  exit 1
+fi
+
+echo "download header-modification passed".
+
 # check if cumulative mods work.
 taler-twister -c ./test_twister.conf \
   -m "hello" -V "world" \
diff --git a/src/test/test_twister_webserver.c b/src/test/test_twister_webserver.c
index bb434c0..bd1c93c 100644
--- a/src/test/test_twister_webserver.c
+++ b/src/test/test_twister_webserver.c
@@ -36,7 +36,7 @@
 
 #define PORT 8080
 
-static int
+static enum MHD_Result
 answer_to_connection
   (void *cls, struct MHD_Connection *connection,
    const char *url, const char *method,
diff --git a/src/twister/taler-twister-service.c b/src/twister/taler-twister-service.c
index 25dea13..4549a52 100644
--- a/src/twister/taler-twister-service.c
+++ b/src/twister/taler-twister-service.c
@@ -344,6 +344,14 @@ static char *modify_path_dl;
  */
 static char *modify_path_ul;
 
+
+/**
+ * If not NULL, the name of the header value to
+ * modify in the response.
+ */
+static char *modify_header_dl;
+
+
 /**
  * If true, will randomly truncate the request body
  * to upload to the proxied service.
@@ -1907,14 +1915,21 @@ create_response (void *cls,
        NULL != header;
        header = header->next)
   {
+    const char *value = header->value;
+    if ((NULL != modify_header_dl) &&
+        (0 == strcmp (header->type,
+                      modify_header_dl)))
+    {
+      value = modify_value;
+    }
     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
                 "Adding MHD response header %s->%s\n",
                 header->type,
-                header->value);
+                value);
     GNUNET_break
       (MHD_YES == MHD_add_response_header (hr->response,
                                            header->type,
-                                           header->value));
+                                           value));
   }
   run_mhd_now ();
 
@@ -2713,6 +2728,56 @@ handle_modify_path_ul (void *cls,
 
 
 /**
+ * Control handler for changing an HTTP response header.
+ *
+ * @param cls message queue for sending replies
+ * @param src received message
+ */
+static int
+check_modify_header_dl (void *cls,
+                      const struct TWISTER_ModifyPath *src)
+{
+  return GNUNET_OK;
+}
+
+
+/**
+ * Control handler for changing an HTTP response header.
+ *
+ * @param cls message queue for sending replies
+ * @param src received message
+ */
+static void
+handle_modify_header_dl (void *cls,
+                         const struct TWISTER_ModifyPath *src)
+{
+  struct GNUNET_SERVICE_Client *c = cls;
+  uint16_t tailsize;
+  char *payload_path;
+  char *payload_value;
+
+  tailsize = ntohs (src->header.size) - sizeof (*src);
+
+  if (tailsize != GNUNET_STRINGS_buffer_tokenize
+        ((const char *) &src[1],
+        tailsize,
+        2,
+        &payload_path,
+        &payload_value))
+  {
+    GNUNET_break_op (0);
+    GNUNET_SERVICE_client_drop (c);
+    return;
+  }
+
+  modify_header_dl = GNUNET_strdup (payload_path);
+  modify_value = GNUNET_strdup (payload_value);
+
+  send_acknowledgement (c);
+}
+
+
+/**
  * Control handler for flipping JSON strings into response objects
  *
  * @param cls message queue for sending replies
@@ -2894,6 +2959,11 @@ GNUNET_SERVICE_MAIN
                          struct TWISTER_ModifyPath,
                          NULL),
 
+  GNUNET_MQ_hd_var_size (modify_header_dl,
+                         TWISTER_MESSAGE_TYPE_MODIFY_HEADER_DL,
+                         struct TWISTER_ModifyPath,
+                         NULL),
+
   GNUNET_MQ_hd_fixed_size (malform_upload,
                            TWISTER_MESSAGE_TYPE_MALFORM_UPLOAD,
                            struct TWISTER_Malform,
diff --git a/src/twister/taler-twister.c b/src/twister/taler-twister.c
index c59cae2..94a9aa8 100644
--- a/src/twister/taler-twister.c
+++ b/src/twister/taler-twister.c
@@ -86,6 +86,11 @@ static char *modify_path_dl;
 static char *modify_path_ul;
 
 /**
+ * Name of the header to modify in the HTTP request.
+ */
+static char *modify_header_dl;
+
+/**
  * New value for the object pointed by `modify_path_(ul|dl)`.
  */
 static char *modify_value;
@@ -151,7 +156,7 @@ run (void *cls,
 {
   tth = TALER_TWISTER_connect (cfg);
   GNUNET_SCHEDULER_add_shutdown (&do_shutdown,
-				 NULL);
+                                 NULL);
   if (NULL == tth)
   {
     GNUNET_break (0);
@@ -172,7 +177,6 @@ run (void *cls,
           &handle_acknowledgement,
           NULL)))
     num_ops++;
-   
 
   if (0 != check_alive)
   {
@@ -250,6 +254,25 @@ run (void *cls,
       num_ops++;
   }
 
+  if (NULL != modify_header_dl)
+  {
+    if (NULL == modify_value)
+    {
+      GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                  "New value not given, give -V|--value also\n");
+      GNUNET_SCHEDULER_shutdown ();
+      return;
+    }
+
+    if (NULL != TALER_TWISTER_modify_header_dl
+        (tth,
+         modify_header_dl,
+         modify_value,
+         &handle_acknowledgement,
+         NULL))
+      num_ops++;
+  }
+
   if (0 == num_ops)
   {
     fprintf (stderr, "No valid hacks specified!\n");
@@ -291,6 +314,15 @@ main (int argc,
        &modify_path_dl),
 
     GNUNET_GETOPT_option_string
+      ('H',
+       "modify-header-dl",
+       "HEADER",
+       gettext_noop
+         ("Modify download HTTP header HEADER,"
+          " require --value.\n"),
+       &modify_header_dl),
+
+    GNUNET_GETOPT_option_string
       ('F',
        "flip-ul",
        "PATH",
@@ -360,13 +392,14 @@ main (int argc,
 
   status = 1;
   if (GNUNET_OK !=
-      GNUNET_PROGRAM_run (argc,
-			  argv,
-			  "taler-twister",
-			  gettext_noop
-			  ("Control taler-twister service."),
-			  options,
-			  &run, NULL))
+      GNUNET_PROGRAM_run (
+        argc,
+        argv,
+        "taler-twister",
+        gettext_noop
+        ("Control taler-twister service."),
+        options,
+        &run, NULL))
     return 2;
   return status;
 }
diff --git a/src/twister/twister.h b/src/twister/twister.h
index 3c00e7c..a83b241 100644
--- a/src/twister/twister.h
+++ b/src/twister/twister.h
@@ -47,6 +47,8 @@
 
 #define TWISTER_MESSAGE_TYPE_FLIP_PATH_UL 9
 
+#define TWISTER_MESSAGE_TYPE_MODIFY_HEADER_DL 10
+
 GNUNET_NETWORK_STRUCT_BEGIN
 struct TWISTER_Malform
 {
diff --git a/src/twister/twister_api.c b/src/twister/twister_api.c
index 7087d62..8bb215b 100644
--- a/src/twister/twister_api.c
+++ b/src/twister/twister_api.c
@@ -380,7 +380,7 @@ TALER_TWISTER_flip_upload
     GNUNET_break (0);
     return NULL;
   }
-  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, 
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
               "Will UL-flip: %s\n",
               path);
 
@@ -555,6 +555,58 @@ TALER_TWISTER_modify_path_ul (struct TALER_TWISTER_Handle *h,
   return op;
 }
 
+
+/**
+ * Change the HTTP response header of @a header to @a value.
+ *
+ * @param h twister instance to control
+ * @param header the HTTP response header to modify
+ * @param value value to use for @a header
+ * @param cb callback to call once twister gets this instruction.
+ * @param cb_cls closure for @a cb_callback
+ *
+ * @return operation handle.
+ */
+struct TALER_TWISTER_Operation *
+TALER_TWISTER_modify_header_dl (struct TALER_TWISTER_Handle *h,
+                                const char *header,
+                                const char *value,
+                                GNUNET_SCHEDULER_TaskCallback cb,
+                                void *cb_cls)
+{
+  struct TALER_TWISTER_Operation *op;
+  struct GNUNET_MQ_Envelope *env;
+  struct TWISTER_ModifyPath *src;
+  uint16_t stralloc;
+
+  stralloc = strlen (header) + strlen (value) + 2;
+  if (sizeof (*src) + stralloc > UINT16_MAX)
+  {
+    GNUNET_break (0);
+    return NULL;
+  }
+  op = GNUNET_new (struct TALER_TWISTER_Operation);
+  op->h = h;
+  op->cb = cb;
+  op->cb_cls = cb_cls;
+  GNUNET_CONTAINER_DLL_insert_tail (h->op_head,
+                                    h->op_tail,
+                                    op);
+  env = GNUNET_MQ_msg_extra (src,
+                             stralloc,
+                             TWISTER_MESSAGE_TYPE_MODIFY_HEADER_DL);
+
+  GNUNET_assert
+    (stralloc == GNUNET_STRINGS_buffer_fill ((char *) &src[1],
+                                             stralloc,
+                                             2,
+                                             header,
+                                             value));
+  GNUNET_MQ_send (h->mq, env);
+  return op;
+}
+
+
 /**
  * Change the next response code to @a new_rc.
  *