-const char parsers_rcs[] = "$Id: parsers.c,v 1.105 2007/08/11 14:49:49 fabiankeil Exp $";
+const char parsers_rcs[] = "$Id: parsers.c,v 1.110 2007/09/29 10:42:37 fabiankeil Exp $";
/*********************************************************************
*
* File : $Source: /cvsroot/ijbswa/current/parsers.c,v $
*
* Revisions :
* $Log: parsers.c,v $
+ * Revision 1.110 2007/09/29 10:42:37 fabiankeil
+ * - Remove "scanning headers for" log message again.
+ * - Some more whitespace fixes.
+ *
+ * Revision 1.109 2007/09/08 14:25:48 fabiankeil
+ * Refactor client_referrer() and add conditional-forge parameter.
+ *
+ * Revision 1.108 2007/08/28 18:21:03 fabiankeil
+ * A bunch of whitespace fixes, pointy hat to me.
+ *
+ * Revision 1.107 2007/08/28 18:16:32 fabiankeil
+ * Fix possible memory corruption in server_http, make sure it's not
+ * executed for ordinary server headers and mark some problems for later.
+ *
+ * Revision 1.106 2007/08/18 14:30:32 fabiankeil
+ * Let content-type-overwrite{} honour force-text-mode again.
+ *
* Revision 1.105 2007/08/11 14:49:49 fabiankeil
* - Add prototpyes for the header parsers and make them static.
* - Comment out client_accept_encoding_adder() which isn't used right now.
static jb_err client_x_forwarded_adder(struct client_state *csp);
static jb_err connection_close_adder (struct client_state *csp);
+static jb_err create_forged_referrer(char **header, const char *hostport);
+static jb_err create_fake_referrer(char **header, const char *fake_referrer);
+static jb_err handle_conditional_hide_referrer_parameter(char **header,
+ const char *host, const int parameter_conditional_block);
+
const struct parsers client_patterns[] = {
{ "referer:", 8, client_referrer },
{ "user-agent:", 11, client_uagent },
};
const struct parsers server_patterns[] = {
- { "HTTP", 4, server_http },
+ { "HTTP/", 5, server_http },
{ "set-cookie:", 11, server_set_cookie },
{ "connection:", 11, connection },
{ "Content-Type:", 13, server_content_type },
NULL
};
-
const add_header_func_ptr add_server_headers[] = {
connection_close_adder,
NULL
};
+/* The vanilla wafer. */
+static const char VANILLA_WAFER[] =
+ "NOTICE=TO_WHOM_IT_MAY_CONCERN_"
+ "Do_not_send_me_any_copyrighted_information_other_than_the_"
+ "document_that_I_am_requesting_or_any_of_its_necessary_components._"
+ "In_particular_do_not_send_me_any_cookies_that_"
+ "are_subject_to_a_claim_of_copyright_by_anybody._"
+ "Take_notice_that_I_refuse_to_be_bound_by_any_license_condition_"
+ "(copyright_or_otherwise)_applying_to_any_cookie._";
+
/*********************************************************************
*
* Function : flush_socket
* This is to protect the parsing of gzipped data,
* but it should(?) be valid for deflated data also.
*/
- log_error (LOG_LEVEL_ERROR, "Buffer too small decompressing iob");
+ log_error(LOG_LEVEL_ERROR, "Buffer too small decompressing iob");
return JB_ERR_COMPRESS;
}
|| (*cur++ != (char)0x8b)
|| (*cur++ != Z_DEFLATED))
{
- log_error (LOG_LEVEL_ERROR, "Invalid gzip header when decompressing");
+ log_error(LOG_LEVEL_ERROR, "Invalid gzip header when decompressing");
return JB_ERR_COMPRESS;
}
else
if (flags & 0xe0)
{
/* The gzip header has reserved bits set; bail out. */
- log_error (LOG_LEVEL_ERROR, "Invalid gzip header flags when decompressing");
+ log_error(LOG_LEVEL_ERROR, "Invalid gzip header flags when decompressing");
return JB_ERR_COMPRESS;
}
cur += 6;
* The number of bytes to skip should be positive
* and we'd like to stay in the buffer.
*/
- if((skip_bytes < 0) || (skip_bytes >= (csp->iob->eod - cur)))
+ if ((skip_bytes < 0) || (skip_bytes >= (csp->iob->eod - cur)))
{
- log_error (LOG_LEVEL_ERROR,
+ log_error(LOG_LEVEL_ERROR,
"Unreasonable amount of bytes to skip (%d). Stopping decompression",
skip_bytes);
return JB_ERR_COMPRESS;
}
- log_error (LOG_LEVEL_INFO,
+ log_error(LOG_LEVEL_INFO,
"Skipping %d bytes for gzip compression. Does this sound right?",
skip_bytes);
cur += skip_bytes;
* the buffer end, we were obviously tricked to skip
* too much.
*/
- log_error (LOG_LEVEL_ERROR,
+ log_error(LOG_LEVEL_ERROR,
"Malformed gzip header detected. Aborting decompression.");
return JB_ERR_COMPRESS;
}
* XXX: The debug level should be lowered
* before the next stable release.
*/
- log_error (LOG_LEVEL_INFO, "Decompressing deflated iob: %d", *cur);
+ log_error(LOG_LEVEL_INFO, "Decompressing deflated iob: %d", *cur);
/*
* In theory (that is, according to RFC 1950), deflate-compressed
* data should begin with a two-byte zlib header and have an
}
else
{
- log_error (LOG_LEVEL_ERROR,
+ log_error(LOG_LEVEL_ERROR,
"Unable to determine compression format for decompression");
return JB_ERR_COMPRESS;
}
*/
if (inflateInit2 (&zstr, -MAX_WBITS) != Z_OK)
{
- log_error (LOG_LEVEL_ERROR, "Error initializing decompression");
+ log_error(LOG_LEVEL_ERROR, "Error initializing decompression");
return JB_ERR_COMPRESS;
}
* We don't modify the existing iob yet, so in case there
* is error in decompression we can recover gracefully.
*/
- buf = zalloc (bufsize);
+ buf = zalloc(bufsize);
if (NULL == buf)
{
- log_error (LOG_LEVEL_ERROR, "Out of memory decompressing iob");
+ log_error(LOG_LEVEL_ERROR, "Out of memory decompressing iob");
return JB_ERR_MEMORY;
}
struct list_entry *h; /* Header */
jb_err err = JB_ERR_OK;
- log_error(LOG_LEVEL_HEADER, "scanning headers for: %s", csp->http->url);
-
for (h = csp->headers->first; (err == JB_ERR_OK) && (h != NULL) ; h = h->next)
{
/* Header crunch()ed in previous run? -> ignore */
* As a side effect it frees the space used by the original
* header lines.
*
+ * XXX: should be split to remove the first_run hack.
+ *
* Parameters :
* 1 : pats = list of patterns to match against headers
* 2 : more_headers = list of functions to add more
/* RegEx failure */
log_error(LOG_LEVEL_ERROR, "Filtering \'%s\' with \'%s\' didn't work out: %s",
*header, b->name, pcrs_strerror(matches));
- if( newheader != NULL)
+ if (newheader != NULL)
{
log_error(LOG_LEVEL_ERROR, "Freeing what's left: %s", newheader);
freez(newheader);
return JB_ERR_OK;
}
+
/*********************************************************************
*
* Function : crunch_server_header
return JB_ERR_OK;
}
+
/*********************************************************************
*
* Function : server_content_disposition
return (*header == NULL) ? JB_ERR_MEMORY : JB_ERR_OK;
}
+
/*********************************************************************
*
* Function : server_last_modified
return JB_ERR_MEMORY;
}
- if(LOG_LEVEL_HEADER & debug) /* Save cycles if the user isn't interested. */
+ if (LOG_LEVEL_HEADER & debug) /* Save cycles if the user isn't interested. */
{
days = rtime / (3600 * 24);
hours = rtime / 3600 % 24;
return JB_ERR_OK;
}
+
/*********************************************************************
*
* Function : client_referrer
*********************************************************************/
static jb_err client_referrer(struct client_state *csp, char **header)
{
- const char *newval;
- const char *host;
- char *referer;
- size_t hostlenght;
+ 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
+ /*
+ * Since the referrer can include the prefix even
* if the request itself is non-forced, we must
- * clean it unconditionally
+ * clean it unconditionally.
+ *
+ * XXX: strclean is too broad
*/
strclean(*header, FORCE_PREFIX);
#endif /* def FEATURE_FORCE_LOAD */
- /*
- * Are we sending referer?
- */
if ((csp->action->flags & ACTION_HIDE_REFERER) == 0)
{
+ /* Nothing left to do */
return JB_ERR_OK;
}
- newval = csp->action->string[ACTION_STRING_REFERER];
+ 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 ((0 != strcmpic(newval, "conditional-block")))
- {
- freez(*header);
- }
- if ((newval == NULL) || (0 == strcmpic(newval, "block")) )
+ if (!parameter_conditional_block && !parameter_conditional_forge)
{
/*
- * Blocking referer
+ * 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 (0 == strcmpic(newval, "conditional-block"))
+ else if (parameter_conditional_block || parameter_conditional_forge)
{
- /*
- * Block referer if host has changed.
- */
-
- if (NULL == (host = strdup(csp->http->hostport)))
- {
- freez(*header);
- log_error(LOG_LEVEL_HEADER, "Referer crunched! Couldn't allocate memory for temporary host copy.");
- return JB_ERR_MEMORY;
- }
- if (NULL == (referer = strdup(*header)))
- {
- freez(*header);
- freez(host);
- log_error(LOG_LEVEL_HEADER, "Referer crunched! Couldn't allocate memory for temporary referer copy.");
- return JB_ERR_MEMORY;
- }
- hostlenght = strlen(host);
- if ( hostlenght < (strlen(referer)-17) ) /*referer begins with 'Referer: http[s]://'*/
- {
- /*Shorten referer to make sure the referer is blocked
- *if www.example.org/www.example.com-shall-see-the-referer/
- *links to www.example.com/
- */
- referer[hostlenght+17] = '\0';
- }
- if ( 0 == strstr(referer, host)) /*Host has changed*/
- {
- log_error(LOG_LEVEL_HEADER, "New host is: %s. Crunching %s!", host, *header);
- freez(*header);
- }
- else
- {
- log_error(LOG_LEVEL_HEADER, "%s (not modified, still on %s)", *header, host);
- }
- freez(referer);
- freez(host);
- return JB_ERR_OK;
+ return handle_conditional_hide_referrer_parameter(header,
+ csp->http->hostport, parameter_conditional_block);
}
- else if (0 != strcmpic(newval, "forge"))
+ else if (0 == strcmpic(parameter, "forge"))
{
- /*
- * We have a specific (fixed) referer we want to send.
- */
- if ((0 != strncmpic(newval, "http://", 7)) && (0 != strncmpic(newval, "https://", 8)))
- {
- log_error(LOG_LEVEL_HEADER, "Parameter: +referrer{%s} is a bad idea, but I don't care.", newval);
- }
- *header = strdup("Referer: ");
- string_append(header, newval);
- log_error(LOG_LEVEL_HEADER, "Referer overwritten with: %s", *header);
-
- return (*header == NULL) ? JB_ERR_MEMORY : JB_ERR_OK;
+ return create_forged_referrer(header, csp->http->hostport);
}
else
{
- /*
- * Forge a referer as http://[hostname:port of REQUEST]/
- * to fool stupid checks for in-site links
- */
-
- *header = strdup("Referer: http://");
- string_append(header, csp->http->hostport);
- string_append(header, "/");
- log_error(LOG_LEVEL_HEADER, "Referer forged to: %s", *header);
-
- return (*header == NULL) ? JB_ERR_MEMORY : JB_ERR_OK;
+ /* interpret parameter as user-supplied referer to fake */
+ return create_fake_referrer(header, parameter);
}
}
+
/*********************************************************************
*
* Function : client_accept_language
return (*header == NULL) ? JB_ERR_MEMORY : JB_ERR_OK;
}
+
/*********************************************************************
*
* Function : client_ua
return JB_ERR_OK;
}
+
/*********************************************************************
*
* Function : client_if_modified_since
else
{
rtime = strtol(newval, &endptr, 0);
- if(rtime)
+ if (rtime)
{
log_error(LOG_LEVEL_HEADER, "Randomizing: %s (random range: %d minut%s)",
*header, rtime, (rtime == 1 || rtime == -1) ? "e": "es");
- if(rtime < 0)
+ if (rtime < 0)
{
rtime *= -1;
negative = 1;
return JB_ERR_MEMORY;
}
- if(LOG_LEVEL_HEADER & debug) /* Save cycles if the user isn't interested. */
+ if (LOG_LEVEL_HEADER & debug) /* Save cycles if the user isn't interested. */
{
hours = rtime / 3600;
minutes = rtime / 60 % 60;
return JB_ERR_OK;
}
+
/*********************************************************************
*
* Function : client_if_none_match
return JB_ERR_OK;
}
+
/*********************************************************************
*
* Function : client_x_filter
{
char *tmp;
struct list_entry *wafer;
- struct list_entry *wafer_list = csp->action->multi[ACTION_MULTI_WAFER]->first;
+ struct list_entry *wafer_list;
jb_err err;
+ /*
+ * If the user has not supplied any wafers, and the user has not
+ * told us to suppress the vanilla wafer, then send the vanilla wafer.
+ */
+ if ((0 != (csp->action->flags & ACTION_VANILLA_WAFER))
+ && list_is_empty(csp->action->multi[ACTION_MULTI_WAFER]))
+ {
+ enlist(csp->action->multi[ACTION_MULTI_WAFER], VANILLA_WAFER);
+ }
+
+ wafer_list = csp->action->multi[ACTION_MULTI_WAFER]->first;
+
if (NULL == wafer_list)
{
/* Nothing to do */
return err;
}
+
#if 0
/*********************************************************************
*
}
#endif
+
/*********************************************************************
*
* Function : client_xtra_adder
if ((csp->action->flags & ACTION_DOWNGRADE) != 0)
{
- (*header)[7] = '0';
- log_error(LOG_LEVEL_HEADER, "Downgraded answer to HTTP/1.0");
+ /* XXX: Should we do a real validity check here? */
+ if (strlen(*header) > 8)
+ {
+ (*header)[7] = '0';
+ log_error(LOG_LEVEL_HEADER, "Downgraded answer to HTTP/1.0");
+ }
+ else
+ {
+ /*
+ * XXX: Should we block the request or
+ * enlist a valid status code line here?
+ */
+ log_error(LOG_LEVEL_INFO, "Malformed server response detected. "
+ "Downgrading to HTTP/1.0 impossible.");
+ }
}
return JB_ERR_OK;
}
#endif /* def FEATURE_FORCE_LOAD */
+
/*********************************************************************
*
* Function : parse_header_time
}
+
/*********************************************************************
*
* Function : get_destination_from_headers
}
+/*********************************************************************
+ *
+ * Function : create_forged_referrer
+ *
+ * Description : Helper for client_referrer to forge a referer as
+ * 'http://[hostname:port/' to fool stupid
+ * checks for in-site links
+ *
+ * Parameters :
+ * 1 : header = Pointer to header pointer
+ * 2 : hostport = Host and optionally port as string
+ *
+ * Returns : JB_ERR_OK in case of success, or
+ * JB_ERR_MEMORY in case of memory problems.
+ *
+ *********************************************************************/
+static jb_err create_forged_referrer(char **header, const char *hostport)
+{
+ assert(NULL == *header);
+
+ *header = strdup("Referer: http://");
+ string_append(header, hostport);
+ string_append(header, "/");
+
+ if (NULL == *header)
+ {
+ return JB_ERR_MEMORY;
+ }
+
+ log_error(LOG_LEVEL_HEADER, "Referer forged to: %s", *header);
+
+ return JB_ERR_OK;
+
+}
+
+
+/*********************************************************************
+ *
+ * Function : create_fake_referrer
+ *
+ * Description : Helper for client_referrer to create a fake referrer
+ * based on a string supplied by the user.
+ *
+ * Parameters :
+ * 1 : header = Pointer to header pointer
+ * 2 : hosthost = Referrer to fake
+ *
+ * Returns : JB_ERR_OK in case of success, or
+ * JB_ERR_MEMORY in case of memory problems.
+ *
+ *********************************************************************/
+static jb_err create_fake_referrer(char **header, const char *fake_referrer)
+{
+ assert(NULL == *header);
+
+ if ((0 != strncmpic(fake_referrer, "http://", 7)) && (0 != strncmpic(fake_referrer, "https://", 8)))
+ {
+ log_error(LOG_LEVEL_HEADER,
+ "Parameter: +hide-referrer{%s} is a bad idea, but I don't care.", fake_referrer);
+ }
+ *header = strdup("Referer: ");
+ string_append(header, fake_referrer);
+
+ if (NULL == *header)
+ {
+ return JB_ERR_MEMORY;
+ }
+
+ log_error(LOG_LEVEL_HEADER, "Referer replaced with: %s", *header);
+
+ return JB_ERR_OK;
+
+}
+
+
+/*********************************************************************
+ *
+ * Function : handle_conditional_hide_referrer_parameter
+ *
+ * Description : Helper for client_referrer to crunch or forge
+ * the referrer header if the host has changed.
+ *
+ * Parameters :
+ * 1 : header = Pointer to header pointer
+ * 2 : host = The target host (may include the port)
+ * 3 : parameter_conditional_block = Boolean to signal
+ * if we're in conditional-block mode. If not set,
+ * we're in conditional-forge mode.
+ *
+ * Returns : JB_ERR_OK in case of success, or
+ * JB_ERR_MEMORY in case of memory problems.
+ *
+ *********************************************************************/
+static jb_err handle_conditional_hide_referrer_parameter(char **header,
+ const char *host, const int parameter_conditional_block)
+{
+ char *referer = strdup(*header);
+ const size_t hostlenght = strlen(host);
+
+ if (NULL == referer)
+ {
+ freez(*header);
+ return JB_ERR_MEMORY;
+ }
+
+ /* referer begins with 'Referer: http[s]://' */
+ if (hostlenght < (strlen(referer)-17))
+ {
+ /*
+ * Shorten referer to make sure the referer is blocked
+ * if www.example.org/www.example.com-shall-see-the-referer/
+ * links to www.example.com/
+ */
+ referer[hostlenght+17] = '\0';
+ }
+ if (NULL == strstr(referer, host))
+ {
+ /* Host has changed */
+ if (parameter_conditional_block)
+ {
+ log_error(LOG_LEVEL_HEADER, "New host is: %s. Crunching %s!", host, *header);
+ freez(*header);
+ }
+ else
+ {
+ freez(*header);
+ freez(referer);
+ return create_forged_referrer(header, host);
+ }
+ }
+ freez(referer);
+
+ return JB_ERR_OK;
+
+}
+
/*
Local Variables:
tab-width: 3
projects / privoxy.git / blobdiff