int
dns_encode_a_response(char *buf, size_t buflen, struct query *q)
/* Only used when iodined gets an A type query for ns.topdomain or www.topdomain */
/* Mostly same as dns_encode_ns_response() above */
{
HEADER *header;
int len;
short name;
char *ipp;
char *p;
if (buflen < sizeof(HEADER))
return 0;
memset(buf, 0, buflen);
header = (HEADER*)buf;
header->id = htons(q->id);
header->qr = 1;
header->opcode = 0;
header->aa = 1;
header->tc = 0;
header->rd = 0;
header->ra = 0;
p = buf + sizeof(HEADER);
header->qdcount = htons(1);
header->ancount = htons(1);
/* pointer to start of name */
name = 0xc000 | ((p - buf) & 0x3fff);
/* Query section */
putname(&p, buflen - (p - buf), q->name); /* Name */
CHECKLEN(4);
putshort(&p, q->type); /* Type */
putshort(&p, C_IN); /* Class */
/* Answer section */
CHECKLEN(12);
putshort(&p, name); /* Name */
putshort(&p, q->type); /* Type */
putshort(&p, C_IN); /* Class */
putlong(&p, 3600); /* TTL */
putshort(&p, 4); /* Data length */
/* ugly hack to output IP address */
ipp = (char *) &q->destination;
CHECKLEN(4);
putbyte(&p, *(ipp++));
putbyte(&p, *(ipp++));
putbyte(&p, *(ipp++));
putbyte(&p, *ipp);
len = p - buf;
return len;
}
/* Takes a format argument and a string argument. Interprets data
* in the string according to the format specification and returns
* that data.
*
* Format characters:
* ? = 1 byte of data to be discarded
* b = signed byte value
* B = unsigned byte value
* c = 1-character string
* f = 4-byte floating-point value (float)
* h = signed 2-byte value (short)
* H = unsigned 2-byte value (short)
* i = signed 4-byte value (int)
* I = unsigned 4-byte value (int)
* l = signed 8-byte value (long long)
* L = unsigned 8-byte value (long long)
* s = string preceded by length (1 byte)
* S = string preceded by length (2 bytes)
* t = string preceded by length (4 bytes)
* v = vector (3 floats totaling 12 bytes)
* z = null-terminated string
*/
static int unpack(lua_State *L)
{
int n;
size_t len;
const char *str;
const char *fmt;
n = lua_gettop(L);
if (n != 2)
return luaL_error(L, "expected 2 arguments for binread function (got %d)", n);
fmt = luaL_checkstring(L, 1);
str = luaL_checklstring(L, 2, &len);
DEBUG(3, "unpack(\"%s\", ...)\n", fmt);
lua_settop(L, 0);
n = 0;
for (; *fmt; fmt++)
{
switch (*fmt)
{
case '?':
CHECKLEN(1);
str = &str[1];
n--;
len--;
break;
case 'b':
CHECKLEN(1);
lua_pushinteger(L, *((signed char *) str));
str = &str[1];
len--;
break;
case 'B':
CHECKLEN(1);
lua_pushinteger(L, *((unsigned char *) str));
str = &str[1];
len--;
break;
case 'c':
CHECKLEN(1);
{
char c[2] = { str[0], '\0' };
lua_pushstring(L, c);
}
str = &str[1];
len--;
break;
case 'f':
CHECKLEN(4);
lua_pushnumber(L, *((float *) str));
str = &str[4];
len -= 4;
break;
case 'h':
CHECKLEN(2);
lua_pushinteger(L, *((short *) str));
str = &str[2];
len -= 2;
break;
case 'H':
CHECKLEN(2);
lua_pushinteger(L, *((unsigned short *) str));
str = &str[2];
len -= 2;
break;
case 'i':
CHECKLEN(4);
lua_pushinteger(L, *((int *) str));
str = &str[4];
len -= 4;
break;
case 'I':
CHECKLEN(4);
lua_pushinteger(L, *((unsigned int *) str));
str = &str[4];
len -= 4;
break;
case 'l':
CHECKLEN(8);
lua_pushnumber(L, *((long long *) str));
str = &str[8];
len -= 8;
break;
case 'L':
CHECKLEN(8);
lua_pushnumber(L, *((unsigned long long *) str));
str = &str[8];
len -= 8;
break;
case 's':
CHECKLEN(1);
{
unsigned char l = str[0];
str = &str[1];
len -= 1;
CHECKLEN(l);
lua_pushlstring(L, str, l);
str = &str[l];
len -= l;
}
break;
case 'S':
CHECKLEN(2);
{
unsigned short l = *((unsigned short *) str);
str = &str[2];
len -= 2;
CHECKLEN(l);
lua_pushlstring(L, str, l);
str = &str[l];
len -= l;
}
break;
case 't':
CHECKLEN(4);
{
unsigned int l = *((unsigned int *) str);
str = &str[4];
len -= 4;
CHECKLEN(l);
lua_pushlstring(L, str, l);
str = &str[l];
len -= l;
}
break;
case 'v':
CHECKLEN(12);
lua_getglobal(L, "vec");
lua_pushnumber(L, *((float *) str));
str = &str[4];
lua_pushnumber(L, *((float *) str));
str = &str[4];
lua_pushnumber(L, *((float *) str));
str = &str[4];
lua_call(L, 3, 1);
len -= 12;
break;
case 'z':
CHECKLEN(1);
{
int l = strlen(str);
lua_pushstring(L, str);
str = &str[l];
len -= l;
}
break;
default:
luaL_error(L, "invalid character '%c' in format string", *fmt);
}
n++;
}
return n;
}
void iap_handlepkt_mode2(const unsigned int len, const unsigned char *buf)
{
static bool poweron_pressed = false;
unsigned int cmd = buf[1];
/* We expect at least three bytes in the buffer, one for the
* lingo, one for the command, and one for the first button
* state bits.
*/
CHECKLEN(3);
/* Lingo 0x02 must have been negotiated */
if (!DEVICE_LINGO_SUPPORTED(0x02)) {
cmd_ack(cmd, IAP_ACK_BAD_PARAM);
return;
}
switch (cmd)
{
/* ContextButtonStatus (0x00)
*
* Transmit button events from the device to the iPod
*
* Packet format (offset in buf[]: Description)
* 0x00: Lingo ID: Simple Remote Lingo, always 0x02
* 0x01: Command, always 0x00
* 0x02: Button states 0:7
* 0x03: Button states 8:15 (optional)
* 0x04: Button states 16:23 (optional)
* 0x05: Button states 24:31 (optional)
*
* Returns: (none)
*/
case 0x00:
{
iap_remotebtn = BUTTON_NONE;
iap_timeoutbtn = 0;
if(buf[2] != 0)
{
if(buf[2] & 1)
REMOTE_BUTTON(BUTTON_RC_PLAY);
if(buf[2] & 2)
REMOTE_BUTTON(BUTTON_RC_VOL_UP);
if(buf[2] & 4)
REMOTE_BUTTON(BUTTON_RC_VOL_DOWN);
if(buf[2] & 8)
REMOTE_BUTTON(BUTTON_RC_RIGHT);
if(buf[2] & 16)
REMOTE_BUTTON(BUTTON_RC_LEFT);
}
else if(len >= 4 && buf[3] != 0)
{
if(buf[3] & 1) /* play */
{
if (audio_status() != AUDIO_STATUS_PLAY)
REMOTE_BUTTON(BUTTON_RC_PLAY);
}
if(buf[3] & 2) /* pause */
{
if (audio_status() == AUDIO_STATUS_PLAY)
REMOTE_BUTTON(BUTTON_RC_PLAY);
}
if(buf[3] & 128) /* Shuffle */
{
if (!iap_btnshuffle)
{
iap_shuffle_state(!global_settings.playlist_shuffle);
iap_btnshuffle = true;
}
}
}
else if(len >= 5 && buf[4] != 0)
{
if(buf[4] & 1) /* repeat */
{
if (!iap_btnrepeat)
{
iap_repeat_next();
iap_btnrepeat = true;
}
}
if (buf[4] & 2) /* power on */
{
poweron_pressed = true;
}
/* Power off
* Not quite sure how to react to this, but stopping playback
* is a good start.
*/
if (buf[4] & 0x04)
{
if (audio_status() == AUDIO_STATUS_PLAY)
REMOTE_BUTTON(BUTTON_RC_PLAY);
}
if(buf[4] & 16) /* ffwd */
REMOTE_BUTTON(BUTTON_RC_RIGHT);
if(buf[4] & 32) /* frwd */
REMOTE_BUTTON(BUTTON_RC_LEFT);
}
/* power on released */
if (poweron_pressed && len >= 5 && !(buf[4] & 2))
{
poweron_pressed = false;
#ifdef HAVE_LINE_REC
/* Belkin TuneTalk microphone sends power-on press+release
* events once authentication sequence is finished,
* GetDevCaps command is ignored by the device when it is
* sent before power-on release event is received.
* XXX: It is unknown if other microphone devices are
* sending the power-on events.
*/
if (DEVICE_LINGO_SUPPORTED(0x01)) {
/* GetDevCaps */
IAP_TX_INIT(0x01, 0x07);
iap_send_tx();
}
#endif
}
break;
}
/* ACK (0x01)
*
* Sent from the iPod to the device
*/
/* ImageButtonStatus (0x02)
*
* Transmit image button events from the device to the iPod
*
* Packet format (offset in buf[]: Description)
* 0x00: Lingo ID: Simple Remote Lingo, always 0x02
* 0x01: Command, always 0x02
* 0x02: Button states 0:7
* 0x03: Button states 8:15 (optional)
* 0x04: Button states 16:23 (optional)
* 0x05: Button states 24:31 (optional)
*
* This command requires authentication
*
* Returns on success:
* IAP_ACK_OK
*
* Returns on failure:
* IAP_ACK_*
*/
case 0x02:
{
if (!DEVICE_AUTHENTICATED) {
cmd_ack(cmd, IAP_ACK_NO_AUTHEN);
break;
}
cmd_ack(cmd, IAP_ACK_CMD_FAILED);
break;
}
/* VideoButtonStatus (0x03)
*
* Transmit video button events from the device to the iPod
*
* Packet format (offset in buf[]: Description)
* 0x00: Lingo ID: Simple Remote Lingo, always 0x02
* 0x01: Command, always 0x03
* 0x02: Button states 0:7
* 0x03: Button states 8:15 (optional)
* 0x04: Button states 16:23 (optional)
* 0x05: Button states 24:31 (optional)
*
* This command requires authentication
*
* Returns on success:
* IAP_ACK_OK
*
* Returns on failure:
* IAP_ACK_*
*/
case 0x03:
{
if (!DEVICE_AUTHENTICATED) {
cmd_ack(cmd, IAP_ACK_NO_AUTHEN);
break;
}
cmd_ack(cmd, IAP_ACK_CMD_FAILED);
break;
}
/* AudioButtonStatus (0x04)
*
* Transmit audio button events from the device to the iPod
*
* Packet format (offset in buf[]: Description)
* 0x00: Lingo ID: Simple Remote Lingo, always 0x02
* 0x01: Command, always 0x04
* 0x02: Button states 0:7
* 0x03: Button states 8:15 (optional)
* 0x04: Button states 16:23 (optional)
* 0x05: Button states 24:31 (optional)
*
* This command requires authentication
*
* Returns on success:
* IAP_ACK_OK
*
* Returns on failure:
* IAP_ACK_*
*/
case 0x04:
{
unsigned char repeatbuf[6];
if (!DEVICE_AUTHENTICATED) {
cmd_ack(cmd, IAP_ACK_NO_AUTHEN);
break;
}
/* This is basically the same command as ContextButtonStatus (0x00),
* with the difference that it requires authentication and that
* it returns an ACK packet to the device.
* So just route it through the handler again, with 0x00 as the
* command
*/
memcpy(repeatbuf, buf, 6);
repeatbuf[1] = 0x00;
iap_handlepkt_mode2((len<6)?len:6, repeatbuf);
cmd_ok(cmd);
break;
}
/* The default response is IAP_ACK_BAD_PARAM */
default:
{
#ifdef LOGF_ENABLE
logf("iap: Unsupported Mode02 Command");
#else
cmd_ack(cmd, IAP_ACK_BAD_PARAM);
#endif
break;
}
}
}
int
dns_encode(char *buf, size_t buflen, struct query *q, qr_t qr, char *data, size_t datalen)
{
HEADER *header;
short name;
char *p;
int len;
int ancnt;
if (buflen < sizeof(HEADER))
return 0;
memset(buf, 0, buflen);
header = (HEADER*)buf;
header->id = htons(q->id);
header->qr = (qr == QR_ANSWER);
header->opcode = 0;
header->aa = (qr == QR_ANSWER);
header->tc = 0;
header->rd = (qr == QR_QUERY);
header->ra = 0;
p = buf + sizeof(HEADER);
switch (qr) {
case QR_ANSWER:
header->qdcount = htons(1);
name = 0xc000 | ((p - buf) & 0x3fff);
/* Question section */
putname(&p, buflen - (p - buf), q->name);
CHECKLEN(4);
putshort(&p, q->type);
putshort(&p, C_IN);
/* Answer section */
if (q->type == T_CNAME || q->type == T_A ||
q->type == T_PTR || q->type == T_AAAA ||
q->type == T_A6 || q->type == T_DNAME) {
/* data is expected to be like "Hblabla.host.name.com\0" */
char *startp;
int namelen;
CHECKLEN(10);
putshort(&p, name);
if (q->type == T_A || q->type == T_AAAA)
/* answer CNAME to A question */
putshort(&p, T_CNAME);
else
putshort(&p, q->type);
putshort(&p, C_IN);
putlong(&p, 0); /* TTL */
startp = p;
p += 2; /* skip 2 bytes length */
if (q->type == T_A6) {
CHECKLEN(1);
putbyte(&p, 128);
}
putname(&p, buflen - (p - buf), data);
CHECKLEN(0);
namelen = p - startp;
namelen -= 2;
putshort(&startp, namelen);
ancnt = 1;
} else if (q->type == T_MX || q->type == T_SRV) {
/* Data is expected to be like
"Hblabla.host.name.com\0Hanother.com\0\0"
For SRV, see RFC2782.
*/
char *mxdata = data;
char *startp;
int namelen;
ancnt = 1;
while (1) {
CHECKLEN(10);
putshort(&p, name);
putshort(&p, q->type);
putshort(&p, C_IN);
putlong(&p, 0); /* TTL */
startp = p;
p += 2; /* skip 2 bytes length */
CHECKLEN(2);
putshort(&p, 10 * ancnt); /* preference */
if (q->type == T_SRV) {
/* weight, port (5060 = SIP) */
CHECKLEN(4);
putshort(&p, 10);
putshort(&p, 5060);
}
putname(&p, buflen - (p - buf), mxdata);
CHECKLEN(0);
namelen = p - startp;
namelen -= 2;
putshort(&startp, namelen);
mxdata = mxdata + strlen(mxdata) + 1;
if (*mxdata == '\0')
break;
ancnt++;
}
} else if (q->type == T_TXT) {
/* TXT has binary or base-X data */
char *startp;
int txtlen;
CHECKLEN(10);
putshort(&p, name);
putshort(&p, q->type);
putshort(&p, C_IN);
putlong(&p, 0); /* TTL */
startp = p;
p += 2; /* skip 2 bytes length */
puttxtbin(&p, buflen - (p - buf), data, datalen);
CHECKLEN(0);
txtlen = p - startp;
txtlen -= 2;
putshort(&startp, txtlen);
ancnt = 1;
} else {
/* NULL has raw binary data */
CHECKLEN(10);
putshort(&p, name);
putshort(&p, q->type);
putshort(&p, C_IN);
putlong(&p, 0); /* TTL */
datalen = MIN(datalen, buflen - (p - buf));
CHECKLEN(2);
putshort(&p, datalen);
CHECKLEN(datalen);
putdata(&p, data, datalen);
CHECKLEN(0);
ancnt = 1;
}
header->ancount = htons(ancnt);
break;
case QR_QUERY:
/* Note that iodined also uses this for forward queries */
header->qdcount = htons(1);
datalen = MIN(datalen, buflen - (p - buf));
putname(&p, datalen, data);
CHECKLEN(4);
putshort(&p, q->type);
putshort(&p, C_IN);
/* EDNS0 to advertise maximum response length
(even CNAME/A/MX, 255+255+header would be >512) */
if (dnsc_use_edns0) {
header->arcount = htons(1);
CHECKLEN(11);
putbyte(&p, 0x00); /* Root */
putshort(&p, 0x0029); /* OPT */
putshort(&p, 0x1000); /* Payload size: 4096 */
putshort(&p, 0x0000); /* Higher bits/edns version */
putshort(&p, 0x8000); /* Z */
putshort(&p, 0x0000); /* Data length */
}
break;
}
len = p - buf;
return len;
}
int
dns_decode(char *buf, size_t buflen, struct query *q, qr_t qr, char *packet, size_t packetlen)
{
char name[QUERY_NAME_SIZE];
char rdata[4*1024];
HEADER *header;
short qdcount;
short ancount;
uint32_t ttl;
unsigned short class;
unsigned short type;
char *data;
unsigned short rlen;
uint16_t id;
int rv;
rv = 0;
header = (HEADER*)packet;
/* Reject short packets */
if (packetlen < sizeof(HEADER))
return 0;
if (header->qr != qr) {
warnx("header->qr does not match the requested qr");
return -1;
}
data = packet + sizeof(HEADER);
qdcount = ntohs(header->qdcount);
ancount = ntohs(header->ancount);
id = ntohs(header->id);
rlen = 0;
if (q != NULL)
q->rcode = header->rcode;
switch (qr) {
case QR_ANSWER:
if(qdcount < 1) {
/* We need a question */
return -1;
}
if (q != NULL)
q->id = id;
/* Read name even if no answer, to give better error message */
readname(packet, packetlen, &data, name, sizeof(name));
CHECKLEN(4);
readshort(packet, &data, &type);
readshort(packet, &data, &class);
/* if CHECKLEN okay, then we're sure to have a proper name */
if (q != NULL) {
/* We only need the first char to check it */
q->name[0] = name[0];
q->name[1] = '\0';
}
if (ancount < 1) {
/* DNS errors like NXDOMAIN have ancount=0 and
stop here. CNAME may also have A; MX/SRV may have
multiple results. */
return -1;
}
/* Here type is still the question type */
if (type == T_NULL || type == T_PRIVATE) {
/* Assume that first answer is what we wanted */
readname(packet, packetlen, &data, name, sizeof(name));
CHECKLEN(10);
readshort(packet, &data, &type);
readshort(packet, &data, &class);
readlong(packet, &data, &ttl);
readshort(packet, &data, &rlen);
rv = MIN(rlen, sizeof(rdata));
rv = readdata(packet, &data, rdata, rv);
if (rv >= 2 && buf) {
rv = MIN(rv, buflen);
memcpy(buf, rdata, rv);
} else {
rv = 0;
}
}
else if ((type == T_A || type == T_CNAME ||
int
dns_encode_ns_response(char *buf, size_t buflen, struct query *q, char *topdomain)
/* Only used when iodined gets an NS type query */
/* Mostly same as dns_encode_a_response() below */
{
HEADER *header;
int len;
short name;
short topname;
short nsname;
char *ipp;
int domain_len;
char *p;
if (buflen < sizeof(HEADER))
return 0;
memset(buf, 0, buflen);
header = (HEADER*)buf;
header->id = htons(q->id);
header->qr = 1;
header->opcode = 0;
header->aa = 1;
header->tc = 0;
header->rd = 0;
header->ra = 0;
p = buf + sizeof(HEADER);
header->qdcount = htons(1);
header->ancount = htons(1);
header->arcount = htons(1);
/* pointer to start of name */
name = 0xc000 | ((p - buf) & 0x3fff);
domain_len = strlen(q->name) - strlen(topdomain);
if (domain_len < 0 || domain_len == 1)
return -1;
if (strcasecmp(q->name + domain_len, topdomain))
return -1;
if (domain_len >= 1 && q->name[domain_len - 1] != '.')
return -1;
/* pointer to start of topdomain; instead of dots at the end
we have length-bytes in front, so total length is the same */
topname = 0xc000 | ((p - buf + domain_len) & 0x3fff);
/* Query section */
putname(&p, buflen - (p - buf), q->name); /* Name */
CHECKLEN(4);
putshort(&p, q->type); /* Type */
putshort(&p, C_IN); /* Class */
/* Answer section */
CHECKLEN(12);
putshort(&p, name); /* Name */
putshort(&p, q->type); /* Type */
putshort(&p, C_IN); /* Class */
putlong(&p, 3600); /* TTL */
putshort(&p, 5); /* Data length */
/* pointer to ns.topdomain */
nsname = 0xc000 | ((p - buf) & 0x3fff);
CHECKLEN(5);
putbyte(&p, 2);
putbyte(&p, 'n');
putbyte(&p, 's');
putshort(&p, topname); /* Name Server */
/* Additional data (A-record of NS server) */
CHECKLEN(12);
putshort(&p, nsname); /* Name Server */
putshort(&p, T_A); /* Type */
putshort(&p, C_IN); /* Class */
putlong(&p, 3600); /* TTL */
putshort(&p, 4); /* Data length */
/* ugly hack to output IP address */
ipp = (char *) &q->destination;
CHECKLEN(4);
putbyte(&p, *(ipp++));
putbyte(&p, *(ipp++));
putbyte(&p, *(ipp++));
putbyte(&p, *ipp);
len = p - buf;
return len;
}
