unbound/dnstap/dnstap_fstrm.c

237 lines
6.9 KiB
C

/*
* dnstap/dnstap_fstrm.c - Frame Streams protocol for dnstap
*
* Copyright (c) 2020, NLnet Labs. All rights reserved.
*
* This software is open source.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* Neither the name of the NLNET LABS nor the names of its contributors may
* be used to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
* TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/
/**
* \file
*
* Definitions for the Frame Streams data transport protocol for
* dnstap message logs.
*/
#include "config.h"
#include "dnstap/dnstap_fstrm.h"
#include "sldns/sbuffer.h"
#include "sldns/wire2str.h"
void* fstrm_create_control_frame_start(char* contenttype, size_t* len)
{
uint32_t* control;
size_t n;
/* start framestream message:
* 4byte 0: control indicator.
* 4byte bigendian: length of control frame
* 4byte bigendian: type START
* 4byte bigendian: option: content-type
* 4byte bigendian: length of string
* string of content type (dnstap)
*/
n = 4+4+4+4+4+strlen(contenttype);
control = malloc(n);
if(!control)
return NULL;
control[0] = 0;
control[1] = htonl(4+4+4+strlen(contenttype));
control[2] = htonl(FSTRM_CONTROL_FRAME_START);
control[3] = htonl(FSTRM_CONTROL_FIELD_TYPE_CONTENT_TYPE);
control[4] = htonl(strlen(contenttype));
memmove(&control[5], contenttype, strlen(contenttype));
*len = n;
return control;
}
void* fstrm_create_control_frame_stop(size_t* len)
{
uint32_t* control;
size_t n;
/* stop framestream message:
* 4byte 0: control indicator.
* 4byte bigendian: length of control frame
* 4byte bigendian: type STOP
*/
n = 4+4+4;
control = malloc(n);
if(!control)
return NULL;
control[0] = 0;
control[1] = htonl(4);
control[2] = htonl(FSTRM_CONTROL_FRAME_STOP);
*len = n;
return control;
}
void* fstrm_create_control_frame_ready(char* contenttype, size_t* len)
{
uint32_t* control;
size_t n;
/* start bidirectional stream:
* 4 bytes 0 escape
* 4 bytes bigendian length of frame
* 4 bytes bigendian type READY
* 4 bytes bigendian frame option content type
* 4 bytes bigendian length of string
* string of content type.
*/
/* len includes the escape and framelength */
n = 4+4+4+4+4+strlen(contenttype);
control = malloc(n);
if(!control) {
return NULL;
}
control[0] = 0;
control[1] = htonl(4+4+4+strlen(contenttype));
control[2] = htonl(FSTRM_CONTROL_FRAME_READY);
control[3] = htonl(FSTRM_CONTROL_FIELD_TYPE_CONTENT_TYPE);
control[4] = htonl(strlen(contenttype));
memmove(&control[5], contenttype, strlen(contenttype));
*len = n;
return control;
}
void* fstrm_create_control_frame_accept(char* contenttype, size_t* len)
{
uint32_t* control;
size_t n;
/* control frame on reply:
* 4 bytes 0 escape
* 4 bytes bigendian length of frame
* 4 bytes bigendian type ACCEPT
* 4 bytes bigendian frame option content type
* 4 bytes bigendian length of string
* string of content type.
*/
/* len includes the escape and framelength */
n = 4+4+4+4+4+strlen(contenttype);
control = malloc(n);
if(!control) {
return NULL;
}
control[0] = 0;
control[1] = htonl(4+4+4+strlen(contenttype));
control[2] = htonl(FSTRM_CONTROL_FRAME_ACCEPT);
control[3] = htonl(FSTRM_CONTROL_FIELD_TYPE_CONTENT_TYPE);
control[4] = htonl(strlen(contenttype));
memmove(&control[5], contenttype, strlen(contenttype));
*len = n;
return control;
}
void* fstrm_create_control_frame_finish(size_t* len)
{
uint32_t* control;
size_t n;
/* control frame on reply:
* 4 bytes 0 escape
* 4 bytes bigendian length of frame
* 4 bytes bigendian type FINISH
*/
/* len includes the escape and framelength */
n = 4+4+4;
control = malloc(n);
if(!control) {
return NULL;
}
control[0] = 0;
control[1] = htonl(4);
control[2] = htonl(FSTRM_CONTROL_FRAME_FINISH);
*len = n;
return control;
}
char* fstrm_describe_control(void* pkt, size_t len)
{
uint32_t frametype = 0;
char buf[512];
char* str = buf;
size_t remain, slen = sizeof(buf);
uint8_t* pos;
buf[0]=0;
if(len < 4) {
snprintf(buf, sizeof(buf), "malformed control frame, "
"too short, len=%u", (unsigned int)len);
return strdup(buf);
}
frametype = sldns_read_uint32(pkt);
if(frametype == FSTRM_CONTROL_FRAME_ACCEPT) {
(void)sldns_str_print(&str, &slen, "accept");
} else if(frametype == FSTRM_CONTROL_FRAME_START) {
(void)sldns_str_print(&str, &slen, "start");
} else if(frametype == FSTRM_CONTROL_FRAME_STOP) {
(void)sldns_str_print(&str, &slen, "stop");
} else if(frametype == FSTRM_CONTROL_FRAME_READY) {
(void)sldns_str_print(&str, &slen, "ready");
} else if(frametype == FSTRM_CONTROL_FRAME_FINISH) {
(void)sldns_str_print(&str, &slen, "finish");
} else {
(void)sldns_str_print(&str, &slen, "type%d", (int)frametype);
}
/* show the content type options */
pos = pkt + 4;
remain = len - 4;
while(remain >= 8) {
uint32_t field_type = sldns_read_uint32(pos);
uint32_t field_len = sldns_read_uint32(pos+4);
if(remain < field_len) {
(void)sldns_str_print(&str, &slen, "malformed_field");
break;
}
if(field_type == FSTRM_CONTROL_FIELD_TYPE_CONTENT_TYPE) {
char tempf[512];
(void)sldns_str_print(&str, &slen, " content-type(");
if(field_len < sizeof(tempf)-1) {
memmove(tempf, pos+8, field_len);
tempf[field_len] = 0;
(void)sldns_str_print(&str, &slen, "%s", tempf);
} else {
(void)sldns_str_print(&str, &slen, "<error-too-long>");
}
(void)sldns_str_print(&str, &slen, ")");
} else {
(void)sldns_str_print(&str, &slen,
" field(type %u, length %u)",
(unsigned int)field_type,
(unsigned int)field_len);
}
pos += 8 + field_len;
remain -= (8 + field_len);
}
if(remain > 0)
(void)sldns_str_print(&str, &slen, " trailing-bytes"
"(length %u)", (unsigned int)remain);
return strdup(buf);
}