/**
* Extract one request header. A header can span multiple lines, in
* which case they will be folded into one before parsing is attempted.
*
* @param[in] connp
* @param[in] data
* @param[in] len
* @return HTP_OK or HTP_ERROR
*/
int htp_process_request_header_generic(htp_connp_t *connp, unsigned char *data, size_t len) {
// Create a new header structure.
htp_header_t *h = calloc(1, sizeof (htp_header_t));
if (h == NULL) return HTP_ERROR;
// Now try to parse the header.
if (htp_parse_request_header_apache_2_2(connp, h, data, len) != HTP_OK) {
free(h);
return HTP_ERROR;
}
#ifdef HTP_DEBUG
fprint_bstr(stderr, "Header name", h->name);
fprint_bstr(stderr, "Header value", h->value);
#endif
// Do we already have a header with the same name?
htp_header_t *h_existing = htp_table_get(connp->in_tx->request_headers, h->name);
if (h_existing != NULL) {
// TODO Do we want to have a list of the headers that are
// allowed to be combined in this way?
// Add to the existing header.
bstr *new_value = bstr_expand(h_existing->value, bstr_len(h_existing->value) + 2 + bstr_len(h->value));
if (new_value == NULL) {
bstr_free(h->name);
bstr_free(h->value);
free(h);
return HTP_ERROR;
}
h_existing->value = new_value;
bstr_add_mem_noex(h_existing->value, (unsigned char *) ", ", 2);
bstr_add_noex(h_existing->value, h->value);
// The new header structure is no longer needed.
bstr_free(h->name);
bstr_free(h->value);
free(h);
// Keep track of repeated same-name headers.
h_existing->flags |= HTP_FIELD_REPEATED;
} else {
// Add as a new header.
htp_table_add(connp->in_tx->request_headers, h->name, h);
}
return HTP_OK;
}
/**
* Extract one request header. A header can span multiple lines, in
* which case they will be folded into one before parsing is attempted.
*
* @param connp
* @return HTP_OK or HTP_ERROR
*/
int htp_process_request_header_apache_2_2(htp_connp_t *connp) {
bstr *tempstr = NULL;
unsigned char *data = NULL;
size_t len = 0;
// Create new header structure
htp_header_t *h = calloc(1, sizeof (htp_header_t));
if (h == NULL) return HTP_ERROR;
// Ensure we have the necessary header data in a single buffer
if (connp->in_header_line_index + 1 == connp->in_header_line_counter) {
// Single line
htp_header_line_t *hl = list_get(connp->in_tx->request_header_lines,
connp->in_header_line_index);
if (hl == NULL) {
// Internal error
htp_log(connp, HTP_LOG_MARK, HTP_LOG_ERROR, 0,
"Process request header (Apache 2.2): Internal error");
free(h);
return HTP_ERROR;
}
data = (unsigned char *) bstr_ptr(hl->line);
len = bstr_len(hl->line);
hl->header = h;
} else {
// Multiple lines (folded)
int i = 0;
for (i = connp->in_header_line_index; i < connp->in_header_line_counter; i++) {
htp_header_line_t *hl = list_get(connp->in_tx->request_header_lines, i);
if (hl == NULL) {
// Internal error
htp_log(connp, HTP_LOG_MARK, HTP_LOG_ERROR, 0,
"Process request header (Apache 2.2): Internal error");
free(h);
return HTP_ERROR;
}
len += bstr_len(hl->line);
}
tempstr = bstr_alloc(len);
if (tempstr == NULL) {
htp_log(connp, HTP_LOG_MARK, HTP_LOG_ERROR, 0,
"Process request header (Apache 2.2): Failed to allocate bstring of %d bytes", len);
free(h);
return HTP_ERROR;
}
for (i = connp->in_header_line_index; i < connp->in_header_line_counter; i++) {
htp_header_line_t *hl = list_get(connp->in_tx->request_header_lines, i);
if (hl == NULL) {
// Internal error
htp_log(connp, HTP_LOG_MARK, HTP_LOG_ERROR, 0,
"Process request header (Apache 2.2): Internal error");
bstr_free(tempstr);
free(h);
return HTP_ERROR;
}
char *data = bstr_ptr(hl->line);
size_t len = bstr_len(hl->line);
htp_chomp((unsigned char *)data, &len);
bstr_add_mem_noex(tempstr, data, len);
hl->header = h;
}
data = (unsigned char *) bstr_ptr(tempstr);
}
// Now try to parse the header
if (htp_parse_request_header_apache_2_2(connp, h, data, len) != HTP_OK) {
// Note: downstream responsible for error logging
if (tempstr != NULL) {
free(tempstr);
}
free(h);
return HTP_ERROR;
}
// Do we already have a header with the same name?
htp_header_t *h_existing = table_get(connp->in_tx->request_headers, h->name);
if (h_existing != NULL) {
// TODO Do we want to keep a list of the headers that are
// allowed to be combined in this way?
// Add to existing header
h_existing->value = bstr_expand(h_existing->value, bstr_len(h_existing->value)
+ 2 + bstr_len(h->value));
bstr_add_mem_noex(h_existing->value, ", ", 2);
bstr_add_str_noex(h_existing->value, h->value);
// The header is no longer needed
if (h->name != NULL)
free(h->name);
if (h->value != NULL)
free(h->value);
free(h);
// Keep track of same-name headers
h_existing->flags |= HTP_FIELD_REPEATED;
} else {
// Add as a new header
table_add(connp->in_tx->request_headers, h->name, h);
}
if (tempstr != NULL) {
free(tempstr);
}
return HTP_OK;
}
