socks5.h

#pragma once

#include "ll.h"
#include <stdio.h>
#include <sys/socket.h>

#define S5LOGF(...) printf(__VA_ARGS__)

#ifdef S5DEBUG
#define S5DLOGF(...) S5LOGF(__VA_ARGS__)
#else
#define S5DLOGF(...)
#endif

typedef unsigned char S5AuthMethod;
typedef unsigned char S5Cmd;
typedef unsigned char S5Atyp;
typedef unsigned char S5Rep;

struct S5ServerCtx {
	LL *userpass;
	int flags;
};

typedef struct S5ServerCtx S5ServerCtx;

#define S5FLAG_NO_AUTH       (1 << 0)
#define S5FLAG_USERPASS_AUTH (1 << 1)

#define S5NO_AUTH             0
#define S5USERPASS_AUTH       2
#define S5INVALID_AUTH_METHOD 0xff

#define S5CMD_CONNECT       1
#define S5CMD_BIND          2
#define S5CMD_UDP_ASSOCIATE 3

#define S5ATYP_IPV4         1
#define S5ATYP_DOMAIN_NAME  3
#define S5ATYP_IPV6         4

#define S5REP_OK                  0
#define S5REP_FAIL                1
#define S5REP_NETWORK_UNREACHABLE 3
#define S5REP_HOST_UNREACHABLE    4
#define S5REP_CONNECTION_REFUSED  5
#define S5REP_CMD_NOT_SUPPORTED   7
#define S5REP_ATYP_NOT_SUPPORTED  8

// int functions below return 0 on success
int s5_server_ctx_init(S5ServerCtx *ctx);
void s5_server_ctx_free(S5ServerCtx *ctx);
int s5_server_add_userpass(S5ServerCtx *ctx, const char *user, const char *pass);
int s5_server_handler(const S5ServerCtx *ctx, int fd);

// returns -1 on error
int s5_create_server(const char *host, const char *port, int backlog, int proto);

char *s5_atyp_str(S5Atyp atyp);
char *s5_cmd_str(S5Cmd cmd);
char *s5_rep_str(S5Rep rep);
char *s5_auth_method_str(S5AuthMethod method);