/* vim: set expandtab ts=4 sw=4: */
/*
* You may redistribute this program and/or modify it under the terms of
* the GNU General Public License as published by the Free Software Foundation,
* either version 3 of the License, or (at your option) any later version.
*
* This program 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 this program. If not, see .
*/
#ifndef RouteHeader_H
#define RouteHeader_H
#include "util/Assert.h"
#include
/**
* The RouteHeader is hidden from the switches by the l2 encryption layer but it is seen
* by every router which hands off the packet.
*
* 1 2 3
* 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* 0 | ver | MTU | Flow ID |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* 4 | |
* + +
* 8 | |
* + Destination IP6 +
* 12 | |
* + +
* 16 | |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*
* Ver is 3 bits representing the protocol version *modulo 8*,
*/
struct RouteHeader
{
uint16_t versionAndMtu_be;
/**
* An arbitrary value created by hashing information which represents the dataflow such
* as protocol (TCP/UDP) and port numbers such that multiple packets which are part of the
* same data flow will will contain the same IDs.
* It is not critical that each dataflow has a unique ID.
* Routers faced with multiple near-best-paths to a given destination, each having a distinct
* bottleneck, may split traffic to optimize usage of each path with reduced risk of packets
* arriving out of order.
* While an implementatin could theoretically use sequencial flowIds such as 1, 2, 3, etc.
* it is in the user's best interest to minimize the number of other flows using the same
* flowId as himself so the optimum choice of flowId is through use of a pseud-random hash
* function.
*/
uint16_t flowId;
/** The destination cjdns address. */
uint8_t destAddr[16];
};
#define RouteHeader_SIZE 20
Assert_compileTime(sizeof(struct RouteHeader) == RouteHeader_SIZE);
static inline void RouteHeader_setVersion(struct RouteHeader* hdr, uint8_t version)
{
type->versionAndMtu_be = (type->versionAndMtu_be & Endian_hostToBigEndian16(0x1fff)) |
Endian_hostToBigEndian16((version % 8) << 13);
}
static inline uint8_t RouteHeader_getVersion(struct RouteHeader* hdr)
{
return Endian_bigEndianToHost16(type->versionAndMtu_be) >> 13;
}
static inline uint16_t RouteHeader_getMTU(struct RouteHeader* hdr)
{
return Endian_bigEndianToHost16(type->versionAndMtu_be) >> 13;
}
* This is to be initialized to what the sending node believes is the full path MTU
* (or 0xffff if unsure) and clamped to the MTU of each path by the routers which forward
* the packet.
#endif
/* vim: set expandtab ts=4 sw=4: */
/*
* You may redistribute this program and/or modify it under the terms of
* the GNU General Public License as published by the Free Software Foundation,
* either version 3 of the License, or (at your option) any later version.
*
* This program 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 this program. If not, see .
*/
#ifndef DataHeader_H
#define DataHeader_H
#include "util/Assert.h"
#include "util/Endian.h"
/**
* 1 2 3
* 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* 0 | ver |R| unused| unused | Content Type |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*
* The DataHeader is protected from the switches by the l2 encryption layer and from the
* routers by the l3 layer of encryption. It's primary uses are to tell the endpoint enough
* information to route the packet to the correct cjdns subsystem and (maybe) reconstruct
* the IPv6 header.
*/
struct DataHeader
{
/**
* If set, the receiving node should respond within 10 milliseconds, if in the next 10
* milliseconds it has something else to send back, this is acceptable, otherwise it should
* synthisize a control packet to respond with.
*/
#define DataHeader_RESPOND_TO_ME (1<<7)
/**
* Version is set to the version of the data as per Version.h
* If the number is over 255, it wraps
*/
uint8_t versionAndFlags;
uint8_t unused;
uint16_t contentType_be;
};
#define DataHeader_SIZE 4
Assert_compileTime(sizeof(struct DataHeader) == DataHeader_SIZE);
enum DataHeader_ContentType
{
/**
* The lowest 255 message types are reserved for cjdns/IPv6 packets.
* AKA: packets where the IP address is within the FC00::/8 block.
* Any packet sent in this way will have the IPv6 header deconstructed and this
* field will come from the nextHeader field in the IPv6 header.
*/
DataHeader_ContentType_IP6_IP = 0,
DataHeader_ContentType_IP6_ICMP = 1,
DataHeader_ContentType_IP6_IGMP = 2,
DataHeader_ContentType_IP6_IPIP = 4,
DataHeader_ContentType_IP6_TCP = 6,
DataHeader_ContentType_IP6_EGP = 8,
DataHeader_ContentType_IP6_PUP = 12,
DataHeader_ContentType_IP6_UDP = 17,
DataHeader_ContentType_IP6_IDP = 22,
DataHeader_ContentType_IP6_TP = 29,
DataHeader_ContentType_IP6_DCCP = 33,
DataHeader_ContentType_IP6_IPV6 = 41,
DataHeader_ContentType_IP6_RSVP = 46,
DataHeader_ContentType_IP6_GRE = 47,
DataHeader_ContentType_IP6_ESP = 50,
DataHeader_ContentType_IP6_AH = 51,
DataHeader_ContentType_IP6_MTP = 92,
DataHeader_ContentType_IP6_BEETPH = 94,
DataHeader_ContentType_IP6_ENCAP = 98,
DataHeader_ContentType_IP6_PIM = 103,
DataHeader_ContentType_IP6_COMP = 108,
DataHeader_ContentType_IP6_SCTP = 132,
DataHeader_ContentType_IP6_UDPLITE = 136,
DataHeader_ContentType_IP6_RAW = 255,
/** Bencoded inter-router CTRL messages. */
DataHeader_ContentType_CTRL = 256,
/**
* Content types in the AVAILABLE range are not defined and can be used
* like port numbers for subsystems of cjdns to communicate with subsystems within
* cjdns on other machines, providing they first agree on which numbers to use via
* CTRL messages.
*/
DataHeader_ContentType_AVAILABLE = 257),
DataHeader_ContentType_AVAILABLE_MAX = 0xffff
};
static inline enum DataHeader_ContentType DataHeader_getContentType(struct DataHeader* hdr)
{
return Endian_bigEndianToHost16(hdr->contentType_be);
}
static inline void DataHeader_setContentType(struct DataHeader* hdr,
enum DataHeader_ContentType type)
{
Assert_true(type <= DataHeader_ContentType_AVAILABLE_MAX);
hdr->contentType_be = Endian_hostToBigEndian16(type);
}
static inline void DataHeader_setRespondToMe(struct DataHeader* hdr, bool rtm)
{
type->versionAndFlags = (type->versionAndFlags & ~DataHeader_RESPOND_TO_ME) |
(rtm) ? DataHeader_RESPOND_TO_ME : 0;
}
static inline bool DataHeader_getRespondToMe(struct DataHeader* hdr)
{
return type->versionAndFlags & DataHeader_RESPOND_TO_ME;
}
static inline void DataHeader_setVersion(struct DataHeader* hdr, uint8_t version)
{
type->versionAndFlags = (type->versionAndFlags & 0x1f) | ((version % 8) << 5);
}
static inline uint8_t DataHeader_getVersion(struct DataHeader* hdr)
{
return type->versionAndFlags >> 5;
}
#endif