/*
BSD 3-Clause License
Copyright (c) 2025, k4m1 <me@k4m1.net>
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:
1. Redistributions of source code must retain the above copyright notice, this
list of conditions and the following disclaimer.
2. 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.
3. Neither the name of the copyright holder 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
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FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
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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
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*/
/* Helpers for creating IPv4 and IPv6 headers */
#ifndef __NETLIB_IP_H__
#define __NETLIB_IP_H__
#include <sys/types.h>
#include <stdint.h>
#include "socket.h"
/* Initialise ip header system */
void ip_initialise(void);
/* Finalise ip header system */
void ip_finalise(void);
/* IPv4 option class definitions */
enum IPV4_OPTION_CLASS {
CONTROL,
DEBUG = 2
};
/* IPv4 option number definitions:
*
* @member END_OF_OPTION_LIST -- This option occupies only 1 octet; it has no length octet.
* @member NO_OPERATION -- This option occupies only 1 octet; it has no length octet
* @member SECURITY -- Used to carry Security, Compartmentation, User Group (TCC), and
* Handling Restriction Codes compatible with DOD requirements.
* @member LOOSE_SOURCE_ROUTING -- Used to route the internet datagram based on information supplied by the source.
* @member INTERNET_TIMESTAMP -- Internet timestamp :b
* @member RECORD_ROUTE -- Used to trace the route an internet datagram takes.
* @member STREAM_ID -- Used to carry the stream identifier.
* @member STRICT_SOURCE_ROUTING -- Used to route the itnernet datagram based on information supplied by the source.
*
*/
enum IPV4_OPTION_NUMBER {
END_OF_OPTION_LIST,
NO_OPERATION,
SECURITY,
LOOSE_SOURCE_ROUTING,
INTERNET_TIMESTAMP,
RECORD_ROUTE = 7,
STREAM_ID = 8,
STRICT_SOURCE_ROUTING = 9
};
/* Option type structure
*
* @member int copied_flags -- Indicates that this option is copied into all fragments of fragmentation
* @member enum IPV4_OPTION_CLASS opt_class -- Is this control or debug/measurement option
* @member enum IPV4_OPTION_NUMBER opt_num -- refer to IPV4_OPTION_NUMBER documentation
*/
typedef struct __attribute__((packed)) {
int copied_flags : 1;
enum IPV4_OPTION_CLASS opt_class : 2;
enum IPV4_OPTION_NUMBER opt_num : 5;
uint8_t option_len;
uint8_t *option_octets;
} ipv4_option_structure;
/* IPv4 Security option security field
*
*/
enum IPV4_SECURITY_SFIELD {
UNCLASSIFIED = 0x0000,
CONFIDENTIAL = 0xF135,
EFTO = 0x789A,
MMMM = 0xBC4D,
PROG = 0x5E26,
RESTRICTED = 0xAF13,
SECRET = 0xD788,
TOP_SECRET = 0x6BC5
};
/* Security option structure
*
* @member enum IPV4_SECURITY_SFIELD -- security classification
* @member uint16_t compartments -- refer to DoD
* @member uint16_t handling_restrictions -- refer to DoD
* @member uint16_t transmission_control_high -- refer to DoD
* @member uint8_t transmission_control_low -- refer to DoD
*/
typedef struct {
enum IPV4_SECURITY_SFIELD sfield;
uint16_t compartments;
uint16_t handling_restrictions;
uint16_t transmission_control_high;
uint8_t transmission_control_low;
} ipv4_security_option_fields ;
/* Possible Type of Service (TOS) precedence values to use
*
* "The Network Control precedence designation is intended to be used
* within a network only.The actual use and control of that
* designation is up to each network. The Internetwork Control
* designation is intended for use by gateway control originators only.
* If the actual use of these precedence designations is of concern to
* a particular network, it is the responsibility of that network to
* control the access to, and use of, those precedence designations."
* -- rfc 791 (https://datatracker.ietf.org/doc/html/rfc791)
*/
enum IPV4_TOS_PRE {
ROUTINE,
PRIORITY,
IMMEDIATE,
FLASH,
FLASH_OVERRIDE,
ECP,
INTERNETWORK_CTRL,
NETWORK_CTRL
};
/* ipv4 flags structure
*
* @member unsigned reserved -- Always 0
* @member unsigned dont_fragment -- set to 1 if packet may be fragmented
* @member unsigned last_fragment -- set to 1 if this is last fragment
*/
enum IPV4_FLAGS {
DONT_FRAGMENT = (1 << 6),
LAST_FRAGMENT = (1 << 7)
};
/* IPv4 specific socket options that can be set for selecting various options
* per connection in use. Not to be confused with internet options.
*
* @member enum IPV4_TOS_PRE pre -- Type of service precedence value
* @member int low_delay -- Normal or low delay
* @member int high_throughput -- Mark this as high throughput datagram
* @member int high_reliability -- Mark this datagram requiring high reliability
* @member uint8_t ttl -- Time to live value to use
* @member struct ipv4_option_structure *options -- Pointer to populated IPv4 options structure if options are used,
* or NULL if not
* @member uint16_t mtu -- Maximum transmission unit
*/
typedef struct __attribute__((packed)) {
unsigned int pre : 3;
unsigned int low_delay : 1;
unsigned int high_throughput : 1;
unsigned int high_reliability : 1;
unsigned int no_fragment : 1;
uint8_t ttl;
ipv4_option_structure *options;
uint16_t mtu;
} ipv4_socket_options;
/* IPv4 Header structure ( https://datatracker.ietf.org/doc/html/rfc791#section-3.1 )
*
* @member unsigned version -- 4 bit version field
* @member unsigned ihl -- internet header length
* @member enum IPV4_TOS_PRE tos -- type of servce
* @member unsigned len -- total length
* @member unsigned id -- identification
* @member unsigned flags -- refer to enum IPV4_FLAGS
* @membef foff -- fragment offset
* @member ttl -- time to live
* @member ptcl -- protocol identifier for next protocol header (icmp, tcp, udp, ..)
* @member csum -- checksum
* @member src -- source ipv4 address
* @member dst -- destination ipv4 address
*/
typedef struct __attribute__((packed)) {
unsigned ihl : 4;
unsigned version : 4;
enum IPV4_TOS_PRE tos : 8;
unsigned len : 16;
unsigned id : 16;
unsigned flags_foff : 16;
unsigned ttl : 8;
unsigned ptcl : 8;
unsigned csum : 16;
unsigned src : 32;
unsigned dst : 32;
} ipv4_hdr;
/* Allocate IPv4 header when non-standard header is required.
*
* @param uint32_t src -- Pointer to source sockaddr_in struct
* @param uint32_t dst -- Pointer to destination sockaddr_in struct
* @param uint8_t tos -- Type of service value
* @param uint16_t f_off_vcf -- Fragment offset and control bits
* @param uint8_t ttl -- Time to live
* @param uint8_t proto -- Protocol
* @param uint8_t option_type -- Type field for additional IPv4 options or 0 if unused
* @param uint8_t option_len -- Length of additional option octets or 0 if unused
* @param uint8_t *option_buf -- Pointer to remaining `option_len` options or 0 if unused
* @param uint16_t tlen -- Amount of bytes in next protocol header
* and payload we're delivering
* @return pointer to populated ipv4 header structure on success or 0 on error
*/
ipv4_hdr *create_ipv4_hdr(uint32_t src,
uint32_t dst, uint8_t tos, uint16_t f_off_vcf,
uint8_t ttl, uint8_t proto, uint8_t option_type, uint8_t option_len,
uint8_t *option_buf, uint16_t tlen);
/* Allocate and populate a default non-priority IPv4 header for user.
* Unless there's a need for high priority delay, reliability or throughput, this
* is likely the type of routine packet header you want.
*
* @param uint32_t src -- Source address to use
* @param uint32_t dst -- Destination address to use
* @param uint8_t proto -- Protocol identification number
* @param uint16_t tlen -- Amount of bytes in next protocol header
* and payload we're delivering
* @return pointer to populated ipv4 header structure
*/
inline ipv4_hdr *create_std_ipv4_hdr(uint32_t src, uint32_t dst,
uint8_t proto, uint16_t tlen) {
return create_ipv4_hdr(src, dst, 16, 0, 64, proto, 0, 0, 0, tlen);
}
/* Transmit datagram over IPv4 protocol
*
* @param net_socket *socket -- Pointer to populated net_socket structure
* @param uint32_t src -- Source address to use
* @param uint32_t dst -- Destination address to use
* @param const void *data -- Pointer to datagram to send, including appropriate
* protocol header
* @param size_t data_len -- Length of datagram to send
* @return size_t amount of bytes sent excluding ip header on success or -1 on error.
* Set errno on error.
*/
size_t ipv4_transmit_datagram(net_socket *socket, uint32_t src,
uint32_t dst, const void *data, size_t data_len);
/* Receive datagram over IPv4 protocol
*
* @param net_socket *socket -- Pointer to populated net_socket structure
* @param const void *dst -- Pointer to memory where we'll write received data to
* @param size_t r_len -- How many bytes do we want to receive *including* IPv4 header
* @return size_t amount of bytes received on success or -1 on error.
* Set errno on error
*/
size_t ipv4_receive_datagram(net_socket *socket, void *dst, size_t r_len);
#endif // __NETLIB_IP_H__