Packet protocol implementation with encryption and compression support. More...

Data Structures
struct	packet_header_t
	Network packet header structure. More...

struct	size_packet_t
	Terminal size update packet. More...

struct	client_info_packet_t
	Client information packet structure. More...

struct	stream_header_t
	Stream header packet structure. More...

struct	client_list_packet_t
	Client list packet structure. More...

struct	server_state_packet_t
	Server state packet structure. More...

struct	error_packet_t
	Error packet structure carrying error code and textual description. More...

struct	remote_log_packet_t
	Remote log packet structure carrying log level and message text. More...

struct	auth_failure_packet_t
	Authentication failure packet structure. More...

struct	protocol_version_packet_t
	Protocol version negotiation packet structure (Packet Type 1) More...

struct	ascii_frame_packet_t
	ASCII frame packet structure (Packet Type 2) More...

struct	image_frame_packet_t
	Image frame packet structure (Packet Type 3) More...

struct	audio_batch_packet_t
	Audio batch packet structure (Packet Type 28) More...

struct	crypto_capabilities_packet_t
	Crypto capabilities packet structure (Packet Type 14) More...

struct	crypto_parameters_packet_t
	Crypto parameters packet structure (Packet Type 15) More...

struct	terminal_capabilities_packet_t
	Terminal capabilities packet structure (Packet Type 5) More...

struct	packet_envelope_t
	Packet envelope containing received packet data. More...

Macros
#define	REMOTE_LOG_FLAG_TRUNCATED 0x0001U
	Remote log packet flag definitions.

Network Protocol Constants
#define	LARGE_PACKET_THRESHOLD (100 * 1024)
	Large packet size threshold (100KB)

#define	MAX_PACKET_SIZE ((size_t)5 * 1024 * 1024)
	Maximum packet size (5MB)

#define	MAX_ERROR_MESSAGE_LENGTH 512
	Maximum error message length (512 bytes)

#define	MAX_REMOTE_LOG_MESSAGE_LENGTH 512
	Maximum remote log message length (512 bytes)

Timeout Configuration Constants
Timeout constants for handling packets of different sizes. Large packets require extended timeouts for successful transmission.
#define	BASE_SEND_TIMEOUT 5
	Base send timeout in seconds (5 seconds)

#define	LARGE_PACKET_EXTRA_TIMEOUT_PER_MB 0.8
	Extra timeout per MB for large packets (0.8 seconds per MB)

#define	MIN_CLIENT_TIMEOUT 10
	Minimum client timeout in seconds (10 seconds)

#define	MAX_CLIENT_TIMEOUT 60
	Maximum client timeout in seconds (60 seconds)

Audio Batching Constants
Audio batching configuration for efficient audio transmission. Batched audio reduces packet overhead and improves bandwidth usage.
#define	AUDIO_BATCH_COUNT 32
	Number of audio chunks per batch (4 chunks)

#define	AUDIO_BATCH_SAMPLES (AUDIO_SAMPLES_PER_PACKET * AUDIO_BATCH_COUNT)
	Total samples in audio batch (8192 samples)

#define	AUDIO_BATCH_MS 186
	Audio batch duration in milliseconds (~186ms)

#define	AUDIO_SAMPLES_PER_PACKET 256
	Samples per audio packet (256 samples)

Protocol Constants
#define	PACKET_MAGIC 0xDEADBEEF
	Packet magic number (0xDEADBEEF)

Multi-User Protocol Constants
#define	ASCIICHAT_DEFAULT_DISPLAY_NAME "AsciiChatter"
	Default display name for clients without a custom name.

Protocol Negotiation Constants
#define	FEATURE_RLE_ENCODING 0x01
	Feature flags for protocol_version_packet_t.

#define	FEATURE_DELTA_FRAMES 0x02
	Delta frame encoding (future)

Client Capability Flags
Bitmask flags for client capabilities in multi-user protocol.
#define	CLIENT_CAP_VIDEO 0x01
	Client can send/receive video.

#define	CLIENT_CAP_AUDIO 0x02
	Client can send/receive audio.

#define	CLIENT_CAP_COLOR 0x04
	Client supports color rendering.

#define	CLIENT_CAP_STRETCH 0x08
	Client can stretch frames to fill terminal.

Stream Type Flags
Bitmask flags for stream types in multi-user protocol.
#define	STREAM_TYPE_VIDEO 0x01
	Video stream.

#define	STREAM_TYPE_AUDIO 0x02
	Audio stream.

Crypto Algorithm Constants
Algorithm identifiers for key exchange, authentication, and encryption. Used in crypto handshake packet negotiation.
#define	KEX_ALGO_X25519 0x01
	X25519 key exchange (Curve25519)

#define	AUTH_ALGO_ED25519 0x01
	Ed25519 authentication (Edwards-curve signatures)

#define	AUTH_ALGO_NONE 0x00
	No authentication (plaintext mode)

#define	CIPHER_ALGO_XSALSA20_POLY1305 0x01
	XSalsa20-Poly1305 authenticated encryption.

Enumerations
enum	packet_type_t { PACKET_TYPE_PROTOCOL_VERSION = 1 , PACKET_TYPE_ASCII_FRAME = 2 , PACKET_TYPE_IMAGE_FRAME = 3 , PACKET_TYPE_AUDIO = 4 , PACKET_TYPE_CLIENT_CAPABILITIES = 5 , PACKET_TYPE_PING = 6 , PACKET_TYPE_PONG = 7 , PACKET_TYPE_CLIENT_JOIN = 8 , PACKET_TYPE_CLIENT_LEAVE = 9 , PACKET_TYPE_STREAM_START = 10 , PACKET_TYPE_STREAM_STOP = 11 , PACKET_TYPE_CLEAR_CONSOLE = 12 , PACKET_TYPE_SERVER_STATE = 13 , PACKET_TYPE_CRYPTO_CAPABILITIES = 14 , PACKET_TYPE_CRYPTO_PARAMETERS = 15 , PACKET_TYPE_CRYPTO_KEY_EXCHANGE_INIT = 16 , PACKET_TYPE_CRYPTO_KEY_EXCHANGE_RESP = 17 , PACKET_TYPE_CRYPTO_AUTH_CHALLENGE = 18 , PACKET_TYPE_CRYPTO_AUTH_RESPONSE = 19 , PACKET_TYPE_CRYPTO_AUTH_FAILED = 20 , PACKET_TYPE_CRYPTO_SERVER_AUTH_RESP = 21 , PACKET_TYPE_CRYPTO_HANDSHAKE_COMPLETE = 22 , PACKET_TYPE_CRYPTO_NO_ENCRYPTION = 23 , PACKET_TYPE_ENCRYPTED = 24 , PACKET_TYPE_CRYPTO_REKEY_REQUEST = 25 , PACKET_TYPE_CRYPTO_REKEY_RESPONSE = 26 , PACKET_TYPE_CRYPTO_REKEY_COMPLETE = 27 , PACKET_TYPE_AUDIO_BATCH = 28 , PACKET_TYPE_SIZE_MESSAGE = 29 , PACKET_TYPE_AUDIO_MESSAGE = 30 , PACKET_TYPE_TEXT_MESSAGE = 31 , PACKET_TYPE_ERROR_MESSAGE = 32 , PACKET_TYPE_REMOTE_LOG = 33 , PACKET_TYPE_AUDIO_OPUS = 34 , PACKET_TYPE_AUDIO_OPUS_BATCH = 35 , PACKET_TYPE_ACIP_SESSION_CREATE = 100 , PACKET_TYPE_ACIP_SESSION_CREATED = 101 , PACKET_TYPE_ACIP_SESSION_LOOKUP = 102 , PACKET_TYPE_ACIP_SESSION_INFO = 103 , PACKET_TYPE_ACIP_SESSION_JOIN = 104 , PACKET_TYPE_ACIP_SESSION_JOINED = 105 , PACKET_TYPE_ACIP_SESSION_LEAVE = 106 , PACKET_TYPE_ACIP_SESSION_END = 107 , PACKET_TYPE_ACIP_SESSION_RECONNECT = 108 , PACKET_TYPE_ACIP_WEBRTC_SDP = 110 , PACKET_TYPE_ACIP_WEBRTC_ICE = 111 , PACKET_TYPE_ACIP_STRING_RESERVE = 120 , PACKET_TYPE_ACIP_STRING_RESERVED = 121 , PACKET_TYPE_ACIP_STRING_RENEW = 122 , PACKET_TYPE_ACIP_STRING_RELEASE = 123 , PACKET_TYPE_ACIP_DISCOVERY_PING = 150 , PACKET_TYPE_ACIP_ERROR = 199 }
	Network protocol packet type enumeration. More...

enum	auth_failure_reason_t { AUTH_FAIL_PASSWORD_REQUIRED = 0x01 , AUTH_FAIL_PASSWORD_INCORRECT = 0x02 , AUTH_FAIL_CLIENT_KEY_REQUIRED = 0x04 , AUTH_FAIL_CLIENT_KEY_REJECTED = 0x08 , AUTH_FAIL_SIGNATURE_INVALID = 0x10 }
	Authentication failure reason flags. More...

enum	packet_recv_result_t { PACKET_RECV_SUCCESS = 0 , PACKET_RECV_EOF = -1 , PACKET_RECV_ERROR = -2 , PACKET_RECV_SECURITY_VIOLATION = -3 }
	Packet reception result codes. More...

Functions
Packet Validation Functions
asciichat_error_t	packet_validate_header (const packet_header_t header, uint16_t pkt_type, uint32_t pkt_len, uint32_t expected_crc)
	Validate packet header and extract information.

asciichat_error_t	packet_validate_crc32 (const void *data, size_t len, uint32_t expected_crc)
	Validate packet CRC32 checksum.

Basic Packet I/O Functions
asciichat_error_t	packet_send (socket_t sockfd, packet_type_t type, const void *data, size_t len)
	Send a packet with header and CRC32 checksum.

asciichat_error_t	packet_receive (socket_t sockfd, packet_type_t type, void data, size_t len)
	Receive a packet with header validation and CRC32 checking.

Secure Packet I/O Functions
asciichat_error_t	send_packet_secure (socket_t sockfd, packet_type_t type, const void data, size_t len, crypto_context_t crypto_ctx)
	Send a packet with encryption and compression support.

packet_recv_result_t	receive_packet_secure (socket_t sockfd, void crypto_ctx, bool enforce_encryption, packet_envelope_t envelope)
	Receive a packet with decryption and decompression support.

Legacy Packet I/O Functions
These functions provide basic packet I/O without encryption support. Use send_packet_secure() and receive_packet_secure() for encryption support.
int	send_packet (socket_t sockfd, packet_type_t type, const void *data, size_t len)
	Send a basic packet without encryption.

int	receive_packet (socket_t sockfd, packet_type_t type, void data, size_t len)
	Receive a basic packet without encryption.

Protocol Packet Functions
Convenience functions for sending specific protocol packets. These functions construct the appropriate packet structure and send it over the socket.
int	send_ping_packet (socket_t sockfd)
	Send a ping packet (keepalive)

int	send_pong_packet (socket_t sockfd)
	Send a pong packet (keepalive response)

int	send_clear_console_packet (socket_t sockfd)
	Send a clear console packet.

asciichat_error_t	packet_send_error (socket_t sockfd, const crypto_context_t crypto_ctx, asciichat_error_t error_code, const char message)
	Send an error packet with optional encryption context.

asciichat_error_t	packet_parse_error_message (const void data, size_t len, asciichat_error_t out_error_code, char message_buffer, size_t message_buffer_size, size_t out_message_length)
	Parse an error packet payload into components.

asciichat_error_t	packet_send_remote_log (socket_t sockfd, const crypto_context_t crypto_ctx, log_level_t level, remote_log_direction_t direction, uint16_t flags, const char message)
	Send a remote log packet with optional encryption context.

asciichat_error_t	packet_parse_remote_log (const void data, size_t len, log_level_t out_level, remote_log_direction_t out_direction, uint16_t out_flags, char message_buffer, size_t message_buffer_size, size_t out_message_length)
	Parse a remote log packet payload into components.

int	send_protocol_version_packet (socket_t sockfd, const protocol_version_packet_t *version)
	Send protocol version negotiation packet.

int	send_crypto_capabilities_packet (socket_t sockfd, const crypto_capabilities_packet_t *caps)
	Send crypto capabilities packet.

int	send_crypto_parameters_packet (socket_t sockfd, const crypto_parameters_packet_t *params)
	Send crypto parameters packet.

asciichat_error_t	send_audio_batch_packet (socket_t sockfd, const float samples, int num_samples, int batch_count, crypto_context_t crypto_ctx)
	Send a batched audio packet with encryption support.

asciichat_error_t	av_send_audio_opus_batch (socket_t sockfd, const uint8_t opus_data, size_t opus_size, const uint16_t frame_sizes, int sample_rate, int frame_duration, int frame_count, crypto_context_t *crypto_ctx)
	Send Opus-encoded audio batch packet with encryption support.

asciichat_error_t	send_ascii_frame_packet (socket_t sockfd, const char *frame_data, size_t frame_size)
	Send ASCII frame packet.

asciichat_error_t	send_image_frame_packet (socket_t sockfd, const void *image_data, uint16_t width, uint16_t height, uint8_t format)
	Send image frame packet.

Detailed Description

Packet protocol implementation with encryption and compression support.

Definition in file packet.h.

Data Structures

Macros

Enumerations

Functions

Detailed Description