/* 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 Headers_H
#define Headers_H
#include "util/Assert.h"
#include "util/Endian.h"
#include
/**
* The header which switches use to decide where to route traffic.
*
* 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 | |
* + Switch Label +
* 4 | |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* 8 | Type | Priority |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*/
#define Headers_SwitchHeader_TYPE_DATA 0
#define Headers_SwitchHeader_TYPE_CONTROL 1
#pragma pack(push)
#pragma pack(4)
struct Headers_SwitchHeader
{
/** The label, this is how the switch decides where to send the packet. Big Endian. */
uint64_t label_be;
/**
* Top 8 bits: messageType
* See: MessageType.h
*
* Bottom 24 bits: priority
* Anti-flooding, this is a big endian uint32_t with the high 8 bits cut off.
*
* This entire number is in big endian encoding.
*/
uint32_t lowBits_be;
};
#define Headers_SwitchHeader_SIZE 12
Assert_compileTime(sizeof(struct Headers_SwitchHeader) == Headers_SwitchHeader_SIZE);
#pragma pack(pop)
static inline uint32_t Headers_getMessageType(const struct Headers_SwitchHeader* header)
{
return Endian_bigEndianToHost32(header->lowBits_be) >> 24;
}
static inline uint32_t Headers_getPriority(const struct Headers_SwitchHeader* header)
{
return Endian_bigEndianToHost32(header->lowBits_be) & ((1 << 24) - 1);
}
static inline void Headers_setPriorityAndMessageType(struct Headers_SwitchHeader* header,
const uint32_t priority,
const uint32_t messageType)
{
header->lowBits_be =
Endian_hostToBigEndian32( (priority & ((1 << 24) - 1)) | messageType << 24 );
}
/**
* Header for nodes authenticating to one another.
*
* 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 | Auth Type | |
* +-+-+-+-+-+-+-+-+ Hash Code +
* 4 | |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* 8 |A| Derivations |S| Additional |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*
* If the 'A' bit is set, the packets in the connection are to be authenticated with Poly1305.
* The Auth Type and Hash Code combined make a lookup key which can be used to scan a hashtable
* to see if the given password is known. It can be thought of as the "username" although it is
* a derivative of the password.
* The number of derivations represents how many times the hash of the password has been hashed
* again. Assuming Alice and Bob have a secure shared secret and Bob and Charlie have a secure
* shared secret, Bob can provide Charlie with a hash of his password with Alice which will allow
* Charlie to then establish a secure connection with Alice, without relying exclusively on
* asymmetrical cryptography.
*
* If the packet has 0 length and the 'S' bit is set then the packet is only intended for helping
* to setup the Cryptoauth session and should be dropped rather than being passed to the user.
*/
union Headers_AuthChallenge
{
struct {
uint8_t type;
uint8_t lookup[7];
/**
* High 1 bit is whether to require poly1305 packet authentication.
* low 15 bits is number of derivations.
*/
uint16_t requirePacketAuthAndDerivationCount;
uint16_t additional;
} challenge;
uint8_t bytes[12];
uint32_t ints[3];
};
/** Total size of the auth structure. */
#define Headers_AuthChallenge_SIZE 12
Assert_compileTime(sizeof(union Headers_AuthChallenge) == Headers_AuthChallenge_SIZE);
/** The number of bytes from the beginning which identify the auth for looking up the secret. */
#define Headers_AuthChallenge_KEYSIZE 8
static inline int Headers_isPacketAuthRequired(union Headers_AuthChallenge* ac)
{
return ac->challenge.requirePacketAuthAndDerivationCount & Endian_hostToBigEndian16(1<<15);
}
static inline int Headers_isSetupPacket(union Headers_AuthChallenge* ac)
{
return ac->challenge.additional & Endian_hostToBigEndian16(1<<15);
}
static inline void Headers_setPacketAuthRequired(union Headers_AuthChallenge* ac,
int require)
{
if (require) {
ac->challenge.requirePacketAuthAndDerivationCount |=
Endian_hostToBigEndian16(1<<15);
} else {
ac->challenge.requirePacketAuthAndDerivationCount &=
Endian_hostToBigEndian16(~(1<<15));
}
}
static inline void Headers_setSetupPacket(union Headers_AuthChallenge* ac, int empty)
{
if (empty) {
ac->challenge.additional |= Endian_hostToBigEndian16(1<<15);
} else {
ac->challenge.additional &= Endian_hostToBigEndian16(~(1<<15));
}
}
static inline uint16_t Headers_getAuthChallengeDerivations(union Headers_AuthChallenge* ac)
{
return Endian_hostToBigEndian16(ac->challenge.requirePacketAuthAndDerivationCount)
& (((uint16_t)~0)>>1);
}
static inline void Headers_setAuthChallengeDerivations(union Headers_AuthChallenge* ac,
uint16_t derivations)
{
ac->challenge.requirePacketAuthAndDerivationCount &=
Endian_hostToBigEndian16(1<<15);
ac->challenge.requirePacketAuthAndDerivationCount |=
Endian_hostToBigEndian16(derivations & ~(1<<15));
}
/**
* This is a handshake header packet, there are 2 required to begin an encrypted connection.
*
* 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 | Session State |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* 4 | |
* + +
* 8 | Auth Challenge |
* + +
* 12 | |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* 16 | |
* + +
* 20 | |
* + +
* 24 | |
* + Random Nonce +
* 28 | |
* + +
* 32 | |
* + +
* 36 | |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* 40 | |
* + +
* 44 | |
* + +
* 48 | |
* + +
* 52 | |
* + Permanent Public Key +
* 56 | |
* + +
* 60 | |
* + +
* 64 | |
* + +
* 68 | |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* 72 | |
* + +
* 76 | |
* + Poly1305 Authenticator +
* 80 | |
* + +
* 84 | |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* 88 | |
* + +
* 92 | |
* + +
* 96 | |
* + +
* 100 | |
* + Encrypted/Authenticated Temporary Public Key +
* 104 | |
* + +
* 108 | |
* + +
* 112 | |
* + +
* 116 | |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | |
* + Variable Length Encrypted/Authenticated Content +
* | |
*
* If "Session State" is equal to the bitwise complement of zero, the sender is requesting
* that the recipient begin a connection with him, this is done in cases when the initiator
* of the connection does not know the key for the recipient. If the entire header is not
* present the recipient MUST drop the packet silently, the only field which is read in the
* packet is the "Permanent Public Key" field, all others SHOULD be ignored, specifically,
* content MUST not be passed on because it cannot be authenticated. The recipient of such a
* packet SHOULD send back a "hello" packet if there is no established connection.
* If there is already a connection over the interface, the recipient SHOULD NOT respond
* but MAY allow the connection to time out faster.
*
* If the "Session State" field is equal to the one or two, the packet is a "hello" packet.
* or a repeated hello packet. If no connection is present, one should be established and the
* recipient MAY send a "key" packet in response but it is RECOMMENDED that he wait until
* he has data to send first. A node who has sent a hello packet and gotten no response and
* now wishes to send more data MUST send that data as more (repeat) hello packets.
*
* If the "Session State" field is equal to two or three, the packet is a "key" packet.
* Key packets are responses to hello packets. Once a node receives a key packet it may begin
* sending data packets. A node who has received a hello packet, sent a key packet and gotten
* no further response who now wishes to send more data MUST send that data as more (repeat)
* key packets.
*/
union Headers_CryptoAuth
{
uint32_t nonce;
struct {
/**
* Numbers one through three are interpreted as handshake packets, UINT32_MAX is
* a connectToMe packet and anything else is a nonce in a traffic packet.
*/
uint32_t handshakeStage;
/** Used for authenticating routers to one another. */
union Headers_AuthChallenge auth;
/** Random nonce for the handshake. */
uint8_t nonce[24];
/** This node's permanent public key. */
uint8_t publicKey[32];
/** This is filled in when the tempKey is encrypted. */
uint8_t authenticator[16];
/** The public key to use for this session, encrypted with the private key. */
uint8_t encryptedTempKey[32];
} handshake;
};
#define Headers_CryptoAuth_SIZE 120
Assert_compileTime(sizeof(union Headers_CryptoAuth) == Headers_CryptoAuth_SIZE);
struct Headers_IP6Header
{
uint16_t versionClassAndFlowLabel;
/** Big Endian. */
uint16_t flowLabelLow_be;
/** Big Endian. */
uint16_t payloadLength_be;
uint8_t nextHeader;
uint8_t hopLimit;
uint8_t sourceAddr[16];
uint8_t destinationAddr[16];
};
#define Headers_IP6Header_SIZE 40
Assert_compileTime(sizeof(struct Headers_IP6Header) == Headers_IP6Header_SIZE);
struct Headers_IP6Fragment
{
uint8_t nextHeader;
uint8_t zero;
uint16_t fragmentOffsetAndMoreFragments_be;
uint32_t identifier;
};
#define Headers_IP6Fragment_SIZE 8
Assert_compileTime(sizeof(struct Headers_IP6Fragment) == Headers_IP6Fragment_SIZE);
#define Headers_IP6Fragment_TYPE 44
static inline uint32_t Headers_IP6Fragment_getOffset(struct Headers_IP6Fragment* frag)
{
return Endian_bigEndianToHost16(frag->fragmentOffsetAndMoreFragments_be) >> 3;
}
static inline void Headers_IP6Fragment_setOffset(struct Headers_IP6Fragment* frag, uint16_t offset)
{
frag->fragmentOffsetAndMoreFragments_be &= Endian_hostToBigEndian16(7);
frag->fragmentOffsetAndMoreFragments_be |= Endian_hostToBigEndian16(offset << 3);
}
static inline int Headers_IP6Fragment_hasMoreFragments(struct Headers_IP6Fragment* frag)
{
return frag->fragmentOffsetAndMoreFragments_be & Endian_hostToBigEndian16(1);
}
static inline void Headers_IP6Fragment_setMoreFragments(struct Headers_IP6Fragment* frag, int more)
{
if (more) {
frag->fragmentOffsetAndMoreFragments_be |= Endian_hostToBigEndian16(1);
} else {
frag->fragmentOffsetAndMoreFragments_be &= Endian_hostToBigEndian16(0xFFFF << 1);
}
}
struct Headers_IP4Header
{
uint8_t versionAndHeaderLength;
uint8_t differentiatedServices;
uint16_t totalLength_be;
uint16_t identification_be;
uint16_t flagsAndFragmentOffset;
uint8_t ttl;
uint8_t protocol;
uint16_t checksum_be;
uint8_t sourceAddr[4];
uint8_t destAddr[4];
};
#define Headers_IP4Header_SIZE 20
Assert_compileTime(sizeof(struct Headers_IP4Header) == Headers_IP4Header_SIZE);
static inline int Headers_getIpVersion(void* header)
{
return (((uint8_t*) header)[0] & 0xF0) >> 4;
}
#define Headers_setIpVersion(header) \
(((uint8_t*) header)[0] |= ( \
(sizeof(*header) == Headers_IP4Header_SIZE) ? 4 : 6 \
) << 4)
struct Headers_UDPHeader {
uint16_t srcPort_be;
uint16_t destPort_be;
uint16_t length_be;
uint16_t checksum_be;
};
#define Headers_UDPHeader_SIZE 8
Assert_compileTime(sizeof(struct Headers_UDPHeader) == Headers_UDPHeader_SIZE);
struct Headers_ICMP6Header {
uint8_t type;
uint8_t code;
uint16_t checksum;
uint32_t additional;
};
#define Headers_ICMP6Header_SIZE 8
Assert_compileTime(sizeof(struct Headers_ICMP6Header) == Headers_ICMP6Header_SIZE);
/**
* A message which is broadcast to signal to other nodes in the local network that they can connect.
*/
#define Headers_Beacon_PASSWORD_LEN 20
struct Headers_Beacon {
uint32_t version_be;
uint8_t password[Headers_Beacon_PASSWORD_LEN];
uint8_t publicKey[32];
};
#define Headers_Beacon_SIZE 56
Assert_compileTime(sizeof(struct Headers_Beacon) == Headers_Beacon_SIZE);
#endif