+ csp->flags |= CSP_FLAG_CHUNKED;
+
+ /*
+ * If the body was modified, it has been de-chunked first
+ * and the header must be removed.
+ *
+ * FIXME: If there is more than one transfer encoding,
+ * only the "chunked" part should be removed here.
+ */
+ if (csp->flags & CSP_FLAG_MODIFIED)
+ {
+ log_error(LOG_LEVEL_HEADER, "Removing: %s", *header);
+ freez(*header);
+ }
+ }
+
+ return JB_ERR_OK;
+}
+
+
+/*********************************************************************
+ *
+ * Function : server_content_encoding
+ *
+ * Description : This function is run twice for each request,
+ * unless FEATURE_ZLIB and filtering are disabled.
+ *
+ * The first run is used to check if the content
+ * is compressed, if FEATURE_ZLIB is disabled
+ * filtering is then disabled as well, if FEATURE_ZLIB
+ * is enabled the content is marked for decompression.
+ *
+ * The second run is used to remove the Content-Encoding
+ * header if the decompression was successful.
+ *
+ * Parameters :
+ * 1 : csp = Current client state (buffers, headers, etc...)
+ * 2 : header = On input, pointer to header to modify.
+ * On output, pointer to the modified header, or NULL
+ * to remove the header. This function frees the
+ * original string if necessary.
+ *
+ * Returns : JB_ERR_OK on success, or
+ * JB_ERR_MEMORY on out-of-memory error.
+ *
+ *********************************************************************/
+static jb_err server_content_encoding(struct client_state *csp, char **header)
+{
+#ifdef FEATURE_ZLIB
+ if ((csp->flags & CSP_FLAG_MODIFIED)
+ && (csp->content_type & (CT_GZIP | CT_DEFLATE)))
+ {
+ /*
+ * We successfully decompressed the content,
+ * and have to clean the header now, so the
+ * client no longer expects compressed data..
+ *
+ * XXX: There is a difference between cleaning
+ * and removing it completely.
+ */
+ log_error(LOG_LEVEL_HEADER, "Crunching: %s", *header);
+ freez(*header);
+ }
+ else if (strstr(*header, "gzip"))
+ {
+ /* Mark for gzip decompression */
+ csp->content_type |= CT_GZIP;
+ }
+ else if (strstr(*header, "deflate"))
+ {
+ /* Mark for zlib decompression */
+ csp->content_type |= CT_DEFLATE;
+ }
+ else if (strstr(*header, "compress"))
+ {
+ /*
+ * We can't decompress this; therefore we can't filter
+ * it either.
+ */
+ csp->content_type |= CT_TABOO;
+ }
+#else /* !defined(FEATURE_ZLIB) */
+ if (strstr(*header, "gzip") || strstr(*header, "compress") || strstr(*header, "deflate"))
+ {
+ /*
+ * Body is compressed, turn off pcrs and gif filtering.
+ */
+ csp->content_type |= CT_TABOO;
+
+ /*
+ * Log a warning if the user expects the content to be filtered.
+ */
+ if ((csp->rlist != NULL) &&
+ (!list_is_empty(csp->action->multi[ACTION_MULTI_FILTER])))
+ {
+ log_error(LOG_LEVEL_INFO,
+ "Compressed content detected, content filtering disabled. "
+ "Consider recompiling Privoxy with zlib support or "
+ "enable the prevent-compression action.");
+ }
+ }
+#endif /* defined(FEATURE_ZLIB) */
+
+ return JB_ERR_OK;
+
+}
+
+
+/*********************************************************************
+ *
+ * Function : server_content_length
+ *
+ * Description : Adjust Content-Length header if we modified
+ * the body.
+ *
+ * Parameters :
+ * 1 : csp = Current client state (buffers, headers, etc...)
+ * 2 : header = On input, pointer to header to modify.
+ * On output, pointer to the modified header, or NULL
+ * to remove the header. This function frees the
+ * original string if necessary.
+ *
+ * Returns : JB_ERR_OK on success, or
+ * JB_ERR_MEMORY on out-of-memory error.
+ *
+ *********************************************************************/
+static jb_err server_content_length(struct client_state *csp, char **header)
+{
+ const size_t max_header_length = 80;
+
+ /* Regenerate header if the content was modified. */
+ if (csp->flags & CSP_FLAG_MODIFIED)
+ {
+ freez(*header);
+ *header = (char *) zalloc(max_header_length);
+ if (*header == NULL)
+ {
+ return JB_ERR_MEMORY;
+ }
+
+ snprintf(*header, max_header_length, "Content-Length: %d",
+ (int)csp->content_length);
+ log_error(LOG_LEVEL_HEADER, "Adjusted Content-Length to %d",
+ (int)csp->content_length);
+ }
+
+ return JB_ERR_OK;
+}
+
+
+/*********************************************************************
+ *
+ * Function : server_content_md5
+ *
+ * Description : Crumble any Content-MD5 headers if the document was
+ * modified. FIXME: Should we re-compute instead?
+ *
+ * Parameters :
+ * 1 : csp = Current client state (buffers, headers, etc...)
+ * 2 : header = On input, pointer to header to modify.
+ * On output, pointer to the modified header, or NULL
+ * to remove the header. This function frees the
+ * original string if necessary.
+ *
+ * Returns : JB_ERR_OK on success, or
+ * JB_ERR_MEMORY on out-of-memory error.
+ *
+ *********************************************************************/
+static jb_err server_content_md5(struct client_state *csp, char **header)
+{
+ if (csp->flags & CSP_FLAG_MODIFIED)
+ {
+ log_error(LOG_LEVEL_HEADER, "Crunching Content-MD5");
+ freez(*header);
+ }
+
+ return JB_ERR_OK;
+}
+
+
+/*********************************************************************
+ *
+ * Function : server_content_disposition
+ *
+ * Description : If enabled, blocks or modifies the "Content-Disposition" header.
+ * Called from `sed'.
+ *
+ * Parameters :
+ * 1 : csp = Current client state (buffers, headers, etc...)
+ * 2 : header = On input, pointer to header to modify.
+ * On output, pointer to the modified header, or NULL
+ * to remove the header. This function frees the
+ * original string if necessary.
+ *
+ * Returns : JB_ERR_OK on success, or
+ * JB_ERR_MEMORY on out-of-memory error.
+ *
+ *********************************************************************/
+static jb_err server_content_disposition(struct client_state *csp, char **header)
+{
+ const char *newval;
+
+ /*
+ * Are we messing with the Content-Disposition header?
+ */
+ if ((csp->action->flags & ACTION_HIDE_CONTENT_DISPOSITION) == 0)
+ {
+ /* Me tinks not */
+ return JB_ERR_OK;
+ }
+
+ newval = csp->action->string[ACTION_STRING_CONTENT_DISPOSITION];
+
+ if ((newval == NULL) || (0 == strcmpic(newval, "block")))
+ {
+ /*
+ * Blocking content-disposition header
+ */
+ log_error(LOG_LEVEL_HEADER, "Crunching %s!", *header);
+ freez(*header);
+ return JB_ERR_OK;
+ }
+ else
+ {
+ /*
+ * Replacing Content-Disposition header
+ */
+ freez(*header);
+ *header = strdup("Content-Disposition: ");
+ string_append(header, newval);
+
+ if (*header != NULL)
+ {
+ log_error(LOG_LEVEL_HEADER,
+ "Content-Disposition header crunched and replaced with: %s", *header);
+ }
+ }
+ return (*header == NULL) ? JB_ERR_MEMORY : JB_ERR_OK;
+}
+
+
+/*********************************************************************
+ *
+ * Function : server_last_modified
+ *
+ * Description : Changes Last-Modified header to the actual date
+ * to help hide-if-modified-since.
+ * Called from `sed'.
+ *
+ * Parameters :
+ * 1 : csp = Current client state (buffers, headers, etc...)
+ * 2 : header = On input, pointer to header to modify.
+ * On output, pointer to the modified header, or NULL
+ * to remove the header. This function frees the
+ * original string if necessary.
+ *
+ * Returns : JB_ERR_OK on success, or
+ * JB_ERR_MEMORY on out-of-memory error.
+ *
+ *********************************************************************/
+static jb_err server_last_modified(struct client_state *csp, char **header)
+{
+ const char *newval;
+ char buf[BUFFER_SIZE];
+
+ char newheader[50];
+#ifdef HAVE_GMTIME_R
+ struct tm gmt;
+#endif
+ struct tm *timeptr = NULL;
+ time_t now, last_modified;
+ long int rtime;
+ long int days, hours, minutes, seconds;
+
+ /*
+ * Are we messing with the Last-Modified header?
+ */
+ if ((csp->action->flags & ACTION_OVERWRITE_LAST_MODIFIED) == 0)
+ {
+ /*Nope*/
+ return JB_ERR_OK;
+ }
+
+ newval = csp->action->string[ACTION_STRING_LAST_MODIFIED];
+
+ if (0 == strcmpic(newval, "block") )
+ {
+ /*
+ * Blocking Last-Modified header. Useless but why not.
+ */
+ log_error(LOG_LEVEL_HEADER, "Crunching %s!", *header);
+ freez(*header);
+ return JB_ERR_OK;
+ }
+ else if (0 == strcmpic(newval, "reset-to-request-time"))
+ {
+ /*
+ * Setting Last-Modified Header to now.
+ */
+ get_http_time(0, buf);
+ freez(*header);
+ *header = strdup("Last-Modified: ");
+ string_append(header, buf);
+
+ if (*header == NULL)
+ {
+ log_error(LOG_LEVEL_HEADER, "Insufficent memory. Last-Modified header got lost, boohoo.");
+ }
+ else
+ {
+ log_error(LOG_LEVEL_HEADER, "Reset to present time: %s", *header);
+ }
+ }
+ else if (0 == strcmpic(newval, "randomize"))
+ {
+ const char *header_time = *header + sizeof("Last-Modified:");
+
+ log_error(LOG_LEVEL_HEADER, "Randomizing: %s", *header);
+ now = time(NULL);
+#ifdef HAVE_GMTIME_R
+ timeptr = gmtime_r(&now, &gmt);
+#elif FEATURE_PTHREAD
+ pthread_mutex_lock(&gmtime_mutex);
+ timeptr = gmtime(&now);
+ pthread_mutex_unlock(&gmtime_mutex);
+#else
+ timeptr = gmtime(&now);
+#endif
+ if (JB_ERR_OK != parse_header_time(header_time, &last_modified))
+ {
+ log_error(LOG_LEVEL_HEADER, "Couldn't parse: %s in %s (crunching!)", header_time, *header);
+ freez(*header);
+ }
+ else
+ {
+ rtime = (long int)difftime(now, last_modified);
+ if (rtime)
+ {
+ int negative = 0;
+
+ if (rtime < 0)
+ {
+ rtime *= -1;
+ negative = 1;
+ log_error(LOG_LEVEL_HEADER, "Server time in the future.");
+ }
+ rtime = pick_from_range(rtime);
+ if (negative) rtime *= -1;
+ last_modified += rtime;
+#ifdef HAVE_GMTIME_R
+ timeptr = gmtime_r(&last_modified, &gmt);
+#elif FEATURE_PTHREAD
+ pthread_mutex_lock(&gmtime_mutex);
+ timeptr = gmtime(&last_modified);
+ pthread_mutex_unlock(&gmtime_mutex);
+#else
+ timeptr = gmtime(&last_modified);
+#endif
+ strftime(newheader, sizeof(newheader), "%a, %d %b %Y %H:%M:%S GMT", timeptr);
+ freez(*header);
+ *header = strdup("Last-Modified: ");
+ string_append(header, newheader);
+
+ if (*header == NULL)
+ {
+ log_error(LOG_LEVEL_ERROR, "Insufficent memory, header crunched without replacement.");
+ return JB_ERR_MEMORY;
+ }
+
+ if (LOG_LEVEL_HEADER & debug) /* Save cycles if the user isn't interested. */
+ {
+ days = rtime / (3600 * 24);
+ hours = rtime / 3600 % 24;
+ minutes = rtime / 60 % 60;
+ seconds = rtime % 60;
+
+ log_error(LOG_LEVEL_HEADER, "Randomized: %s (added %d da%s %d hou%s %d minut%s %d second%s",
+ *header, days, (days == 1) ? "y" : "ys", hours, (hours == 1) ? "r" : "rs",
+ minutes, (minutes == 1) ? "e" : "es", seconds, (seconds == 1) ? ")" : "s)");
+ }
+ }
+ else
+ {
+ log_error(LOG_LEVEL_HEADER, "Randomized ... or not. No time difference to work with.");
+ }
+ }
+ }
+
+ return JB_ERR_OK;
+}
+
+
+/*********************************************************************
+ *
+ * Function : client_accept_encoding
+ *
+ * Description : Rewrite the client's Accept-Encoding header so that
+ * if doesn't allow compression, if the action applies.
+ * Note: For HTTP/1.0 the absence of the header is enough.
+ *
+ * Parameters :
+ * 1 : csp = Current client state (buffers, headers, etc...)
+ * 2 : header = On input, pointer to header to modify.
+ * On output, pointer to the modified header, or NULL
+ * to remove the header. This function frees the
+ * original string if necessary.
+ *
+ * Returns : JB_ERR_OK on success, or
+ * JB_ERR_MEMORY on out-of-memory error.
+ *
+ *********************************************************************/
+static jb_err client_accept_encoding(struct client_state *csp, char **header)
+{
+ if ((csp->action->flags & ACTION_NO_COMPRESSION) != 0)
+ {
+ log_error(LOG_LEVEL_HEADER, "Suppressed offer to compress content");
+
+ freez(*header);
+
+ /* Temporarily disable the correct behaviour to
+ * work around a PHP bug.
+ *
+ * if (!strcmpic(csp->http->ver, "HTTP/1.1"))
+ * {
+ * *header = strdup("Accept-Encoding: identity;q=1.0, *;q=0");
+ * if (*header == NULL)
+ * {
+ * return JB_ERR_MEMORY;
+ * }
+ * }
+ *
+ */
+ }
+
+ return JB_ERR_OK;
+}
+
+
+/*********************************************************************
+ *
+ * Function : client_te
+ *
+ * Description : Rewrite the client's TE header so that
+ * if doesn't allow compression, if the action applies.
+ *
+ * Parameters :
+ * 1 : csp = Current client state (buffers, headers, etc...)
+ * 2 : header = On input, pointer to header to modify.
+ * On output, pointer to the modified header, or NULL
+ * to remove the header. This function frees the
+ * original string if necessary.
+ *
+ * Returns : JB_ERR_OK on success, or
+ * JB_ERR_MEMORY on out-of-memory error.
+ *
+ *********************************************************************/
+static jb_err client_te(struct client_state *csp, char **header)
+{
+ if ((csp->action->flags & ACTION_NO_COMPRESSION) != 0)
+ {
+ freez(*header);
+ log_error(LOG_LEVEL_HEADER, "Suppressed offer to compress transfer");
+ }
+
+ return JB_ERR_OK;
+}
+
+
+/*********************************************************************
+ *
+ * Function : client_referrer
+ *
+ * Description : Handle the "referer" config setting properly.
+ * Called from `sed'.
+ *
+ * Parameters :
+ * 1 : csp = Current client state (buffers, headers, etc...)
+ * 2 : header = On input, pointer to header to modify.
+ * On output, pointer to the modified header, or NULL
+ * to remove the header. This function frees the
+ * original string if necessary.
+ *
+ * Returns : JB_ERR_OK on success, or
+ * JB_ERR_MEMORY on out-of-memory error.
+ *
+ *********************************************************************/
+static jb_err client_referrer(struct client_state *csp, char **header)
+{
+ const char *parameter;
+ /* booleans for parameters we have to check multiple times */
+ int parameter_conditional_block;
+ int parameter_conditional_forge;
+
+#ifdef FEATURE_FORCE_LOAD
+ /*
+ * Since the referrer can include the prefix even
+ * if the request itself is non-forced, we must
+ * clean it unconditionally.
+ *
+ * XXX: strclean is too broad
+ */
+ strclean(*header, FORCE_PREFIX);
+#endif /* def FEATURE_FORCE_LOAD */
+
+ if ((csp->action->flags & ACTION_HIDE_REFERER) == 0)
+ {
+ /* Nothing left to do */
+ return JB_ERR_OK;
+ }
+
+ parameter = csp->action->string[ACTION_STRING_REFERER];
+ assert(parameter != NULL);
+ parameter_conditional_block = (0 == strcmpic(parameter, "conditional-block"));
+ parameter_conditional_forge = (0 == strcmpic(parameter, "conditional-forge"));
+
+ if (!parameter_conditional_block && !parameter_conditional_forge)
+ {
+ /*
+ * As conditional-block and conditional-forge are the only
+ * parameters that rely on the original referrer, we can
+ * remove it now for all the others.
+ */
+ freez(*header);
+ }
+
+ if (0 == strcmpic(parameter, "block"))
+ {
+ log_error(LOG_LEVEL_HEADER, "Referer crunched!");
+ return JB_ERR_OK;
+ }
+ else if (parameter_conditional_block || parameter_conditional_forge)
+ {
+ return handle_conditional_hide_referrer_parameter(header,
+ csp->http->hostport, parameter_conditional_block);
+ }
+ else if (0 == strcmpic(parameter, "forge"))
+ {
+ return create_forged_referrer(header, csp->http->hostport);
+ }
+ else
+ {
+ /* interpret parameter as user-supplied referer to fake */
+ return create_fake_referrer(header, parameter);
+ }
+}
+
+
+/*********************************************************************
+ *
+ * Function : client_accept_language
+ *
+ * Description : Handle the "Accept-Language" config setting properly.
+ * Called from `sed'.
+ *
+ * Parameters :
+ * 1 : csp = Current client state (buffers, headers, etc...)
+ * 2 : header = On input, pointer to header to modify.
+ * On output, pointer to the modified header, or NULL
+ * to remove the header. This function frees the
+ * original string if necessary.
+ *
+ * Returns : JB_ERR_OK on success, or
+ * JB_ERR_MEMORY on out-of-memory error.
+ *
+ *********************************************************************/
+static jb_err client_accept_language(struct client_state *csp, char **header)
+{
+ const char *newval;
+
+ /*
+ * Are we messing with the Accept-Language?
+ */
+ if ((csp->action->flags & ACTION_HIDE_ACCEPT_LANGUAGE) == 0)
+ {
+ /*I don't think so*/
+ return JB_ERR_OK;
+ }
+
+ newval = csp->action->string[ACTION_STRING_LANGUAGE];
+
+ if ((newval == NULL) || (0 == strcmpic(newval, "block")) )
+ {
+ /*
+ * Blocking Accept-Language header
+ */
+ log_error(LOG_LEVEL_HEADER, "Crunching Accept-Language!");
+ freez(*header);
+ return JB_ERR_OK;
+ }
+ else
+ {
+ /*
+ * Replacing Accept-Language header
+ */
+ freez(*header);
+ *header = strdup("Accept-Language: ");
+ string_append(header, newval);
+
+ if (*header == NULL)
+ {
+ log_error(LOG_LEVEL_ERROR,
+ "Insufficent memory. Accept-Language header crunched without replacement.");
+ }
+ else
+ {
+ log_error(LOG_LEVEL_HEADER,
+ "Accept-Language header crunched and replaced with: %s", *header);
+ }
+ }
+ return (*header == NULL) ? JB_ERR_MEMORY : JB_ERR_OK;
+}
+
+
+/*********************************************************************
+ *
+ * Function : crunch_client_header
+ *
+ * Description : Crunch client header if it matches a string supplied by the
+ * user. Called from `sed'.
+ *
+ * Parameters :
+ * 1 : csp = Current client state (buffers, headers, etc...)
+ * 2 : header = On input, pointer to header to modify.
+ * On output, pointer to the modified header, or NULL
+ * to remove the header. This function frees the
+ * original string if necessary.
+ *
+ * Returns : JB_ERR_OK on success and always succeeds
+ *
+ *********************************************************************/
+static jb_err crunch_client_header(struct client_state *csp, char **header)
+{
+ const char *crunch_pattern;
+
+ /* Do we feel like crunching? */
+ if ((csp->action->flags & ACTION_CRUNCH_CLIENT_HEADER))
+ {
+ crunch_pattern = csp->action->string[ACTION_STRING_CLIENT_HEADER];