other_mirrors/iodine
1
0
Fork 0
mirror of https://github.com/yarrick/iodine.git synced 2024-12-22 21:33:33 +02:00
Code Issues Projects Releases Packages Wiki Activity

Move encoding to its own file

Browse source
This commit is contained in:
Erik Ekman 2006-08-12 23:24:59 +00:00
parent c7dae6e979
commit b14b23c936
4 changed files with 124 additions and 71 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

4
Makefile
View file

@ -1,8 +1,8 @@
CC = gcc
CLIENT = iodine
CLIENTOBJS = iodine.o tun.o dns.o read.o
CLIENTOBJS = iodine.o tun.o dns.o read.o encoding.o
SERVER = iodined
SERVEROBJS = iodined.o tun.o dns.o read.o
SERVEROBJS = iodined.o tun.o dns.o read.o encoding.o
OS = `uname | tr "a-z" "A-Z"`

77
dns.c
View file

@ -35,11 +35,8 @@
#include "read.h"
#include "structs.h"
#include "dns.h"
#include "encoding.h"
// For FreeBSD
#ifndef MIN
#define MIN(a,b) ((a)<(b)?(a):(b))
#endif
static int host2dns(const char *, char *, int);
static int dns_write(int, int, char *, int, char);
@ -221,66 +218,28 @@ dns_query(int fd, int id, char *host, int type)
sendto(fd, buf, len, 0, (struct sockaddr*)&peer, peerlen);
}
static void
put_hex(char *p, char h)
{
int t;
static const char to_hex[] = "0123456789ABCDEF";
t = (h & 0xF0) >> 4;
p[0] = to_hex[t];
t = h & 0x0F;
p[1] = to_hex[t];
}
static int
dns_write(int fd, int id, char *buf, int len, char flag)
{
int avail;
int i;
int final;
int written;
int encoded;
char data[257];
char *d;
#define CHUNK 31
// 31 bytes expands to 62 chars in domain
// We just use hex as encoding right now
avail = 0xFF - strlen(topdomain) - 2;
avail /= 2; // use two chars per byte in encoding
avail -= (avail/CHUNK); // make space for parts
avail = MIN(avail, len); // do not use more bytes than is available;
final = (avail == len); // is this the last block?
bzero(data, sizeof(data));
d = data;
if (flag != 0) {
*d = flag;
} else {
// First byte is 0 for middle packet and 1 for last packet
*d = '0' + final;
}
d++;
if (len > 0) {
for (i = 0; i < avail; i++) {
if (i > 0 && i % 31 == 0) {
*d = '.';
d++;
}
put_hex(d, buf[i]);
d += 2;
}
}
written = encode_data(buf, len, avail, d, flag);
encoded = strlen(data);
d += encoded;
if (*d != '.') {
*d++ = '.';
}
strncpy(d, topdomain, strlen(topdomain)+1);
dns_query(fd, id, data, T_NULL);
return avail;
return written;
}
int
@ -433,32 +392,12 @@ dnsd_send(int fd, struct query *q, char *data, int datalen)
static int
decodepacket(const char *name, char *buf, int buflen)
{
int r;
int len;
char *dp;
char *domain;
const char *np;
len = 1;
domain = strstr(name, topdomain);
buf[0] = name[0];
dp = buf + 1;
np = name + 1;
while(len < buflen && np < domain) {
if(*np == '.') {
np++;
continue;
}
sscanf(np, "%02X", &r);
*dp++ = (char)r;
np+=2;
len++;
}
len = decode_data(buf, buflen, name, domain);
if (len == buflen)
return -1;
return len;

91
encoding.c Normal file
View file

@ -0,0 +1,91 @@
/*
* Copyright (c) 2006 Bjorn Andersson <flex@kryo.se>, Erik Ekman <yarrick@kryo.se>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <stdio.h>
// For FreeBSD
#ifndef MIN
#define MIN(a,b) ((a)<(b)?(a):(b))
#endif
static const char to_hex[] = "0123456789ABCDEF";
int
encode_data(char *buf, int len, int space, char *dest, char flag)
{
int final;
int write;
int i;
int t;
#define CHUNK 31
// 31 bytes expands to 62 chars in domain
// We just use hex as encoding right now
write = space / 2; // use two chars per byte in encoding
write -= (write/CHUNK); // make space for parts
write = MIN(write, len); // do not use more bytes than is available;
final = (write == len); // is this the last block?
if (flag != 0) {
*dest = flag;
} else {
// First byte is 0 for middle packet and 1 for last packet
*dest = '0' + final;
}
dest++;
if (len > 0) {
for (i = 0; i < write; i++) {
if (i > 0 && i % CHUNK == 0) {
*dest = '.';
dest++;
}
t = (buf[i] & 0xF0) >> 4;
*dest++ = to_hex[t];
t = buf[i] & 0x0F;
*dest++ = to_hex[t];
}
}
return write;
}
int
decode_data(char *dest, int size, const char *src, char *srcend)
{
int r;
int len;
len = 1;
*dest = *src;
dest++;
src++;
while(len < size && src < srcend) {
if(*src == '.') {
src++;
continue;
}
sscanf(src, "%02X", &r);
*dest++ = (char)r;
src+=2;
len++;
}
return len;
}

23
encoding.h Normal file
View file

@ -0,0 +1,23 @@
/*
* Copyright (c) 2006 Bjorn Andersson <flex@kryo.se>, Erik Ekman <yarrick@kryo.se>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#ifndef _ENCODING_H_
#define _ENCODING_H_
int encode_data(char *, int, int, char *, char);
int decode_data(char *, int, const char *, char *);
#endif /* _ENCODING_H_ */