io.pkts.packet.sip.impl.SipParser Maven / Gradle / Ivy
/**
*
*/
package io.pkts.packet.sip.impl;
import io.pkts.buffer.Buffer;
import io.pkts.buffer.Buffers;
import io.pkts.packet.sip.SipMessage;
import io.pkts.packet.sip.SipParseException;
import io.pkts.packet.sip.header.CSeqHeader;
import io.pkts.packet.sip.header.CallIdHeader;
import io.pkts.packet.sip.header.ContactHeader;
import io.pkts.packet.sip.header.ContentLengthHeader;
import io.pkts.packet.sip.header.ContentTypeHeader;
import io.pkts.packet.sip.header.ExpiresHeader;
import io.pkts.packet.sip.header.FromHeader;
import io.pkts.packet.sip.header.MaxForwardsHeader;
import io.pkts.packet.sip.header.RecordRouteHeader;
import io.pkts.packet.sip.header.RouteHeader;
import io.pkts.packet.sip.header.SipHeader;
import io.pkts.packet.sip.header.ToHeader;
import io.pkts.packet.sip.header.ViaHeader;
import io.pkts.packet.sip.header.impl.SipHeaderImpl;
import java.io.IOException;
import java.nio.charset.Charset;
import java.text.ParseException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.function.Function;
/**
* Basic sip parser that contains most (all?) of the different grammar rules for SIP as defined by
* RFC 3261. View these various methods as building blocks for building up a complete SIP parser
* (perhaps I should rename this class?).
*
* All of these functions work in the following way:
*
* - consumeXXXX - will (in general) simply try and consume whatever it is supposed to
* consume and the function will return true of false depending on whether is was able to consume
* anything from the {@link Buffer}. The consume-functions will (if successful) move the reader
* index of the {@link Buffer}. If unsuccessful, the reader index will be left untouched.
* - expectXXX - will (in general) expect that the next thing is whatever it is supposed to
* expect. These functions are really the same as the consumeXXXX ones but instead of returning true
* or false the expect-functions will throw a {@link SipParseException} to indicate that things
* didn't turn out as we were hoping for. Also, remember that the {@link SipParseException} contains
* the error offset into the {@link Buffer} where things broke. As with the consume-functions, the
* expect-functions will (if successful) move the reader index of the {@link Buffer}
*
*
*
* @author [email protected]
*/
public class SipParser {
private static final String UNABLE_TO_READ_FROM_STREAM = "Unable to read from stream";
/**
* There are many situations where you are looking to frame something but
* you cannot find the terminating condition. Since an attacker could easily
* just have you read a never ending stream we need at some point give up
* and abort.
*/
public static final int MAX_LOOK_AHEAD = 1024;
public static final Buffer INVITE = Buffers.wrap("INVITE");
public static final Buffer ACK = Buffers.wrap("ACK");
public static final Buffer CANCEL = Buffers.wrap("CANCEL");
public static final Buffer BYE = Buffers.wrap("BYE");
public static final Buffer SUBSCRIBE = Buffers.wrap("SUBSCRIBE");
public static final Buffer NOTIFY = Buffers.wrap("NOTIFY");
public static final Buffer PUBLISH = Buffers.wrap("PUBLISH");
public static final Buffer INFO = Buffers.wrap("INFO");
public static final Buffer OPTIONS = Buffers.wrap("OPTIONS");
public static final Buffer REGISTER = Buffers.wrap("REGISTER");
public static final Buffer PRACK = Buffers.wrap("PRACK");
public static final Buffer REFER = Buffers.wrap("REFER");
public static final Buffer MESSAGE = Buffers.wrap("MESSAGE");
public static final Buffer UPDATE = Buffers.wrap("UPDATE");
public static final Buffer TAG = Buffers.wrap("tag");
public static final Buffer USER = Buffers.wrap("user");
public static final Buffer TTL = Buffers.wrap("ttl");
public static final Buffer MADDR = Buffers.wrap("maddr");
public static final Buffer METHOD = Buffers.wrap("method");
public static final Buffer TRANSPORT = Buffers.wrap("transport");
public static final Buffer TRANSPORT_EQ = Buffers.wrap("transport=");
public static final Buffer SIP2_0 = Buffers.wrap("SIP/2.0");
public static final Buffer SIP2_0_SLASH = Buffers.wrap("SIP/2.0/");
public static final Buffer SCHEME_SIP = Buffers.wrap("sip");
public static final Buffer SCHEME_SIP_COLON = Buffers.wrap("sip:");
public static final Buffer SCHEME_SIPS = Buffers.wrap("sips");
public static final Buffer SCHEME_SIPS_COLON = Buffers.wrap("sips:");
public static final Buffer SCHEME_TEL = Buffers.wrap("tel");
public static final Buffer SCHEME_TEL_COLON = Buffers.wrap("tel:");
public static final byte AT = '@';
public static final byte COLON = ':';
public static final byte SEMI = ';';
public static final byte DOUBLE_QOUTE = '"';
public static final byte CR = '\r';
public static final byte LF = '\n';
public static final byte SP = ' ';
public static final byte HTAB = '\t';
public static final byte DASH = '-';
public static final byte PERIOD = '.';
public static final byte COMMA = ',';
public static final byte EXCLAMATIONPOINT = '!';
public static final byte PERCENT = '%';
public static final byte STAR = '*';
public static final byte UNDERSCORE = '_';
public static final byte QUESTIONMARK = '?';
public static final byte PLUS = '+';
public static final byte BACKTICK = '`';
public static final byte TICK = '\'';
public static final byte TILDE = '~';
public static final byte EQ = '=';
public static final byte SLASH = '/';
public static final byte BACK_SLASH = '\\';
/**
* Left parenthesis
*/
public static final byte LPAREN = '(';
/**
* Right parenthesis
*/
public static final byte RPAREN = ')';
/**
* Right angle quote
*/
public static final byte RAQUOT = '>';
/**
* Left angle quote
*/
public static final byte LAQUOT = '<';
/**
* Double quotation mark
*/
public static final byte DQUOT = '"';
public static final Buffer UDP = Buffers.wrap("udp");
public static final Buffer TCP = Buffers.wrap("tcp");
public static final Buffer TLS = Buffers.wrap("tls");
public static final Buffer SCTP = Buffers.wrap("sctp");
public static final Buffer WS = Buffers.wrap("ws");
public static final Buffer WSS = Buffers.wrap("wss");
public static final Map> framers = new HashMap<>();
static {
framers.put(CallIdHeader.NAME, header -> CallIdHeader.frame(header.getValue()));
framers.put(CallIdHeader.COMPACT_NAME, header -> CallIdHeader.frameCompact(header.getValue()));
framers.put(ContactHeader.NAME, header -> ContactHeader.frame(header.getValue()));
framers.put(ContactHeader.COMPACT_NAME, header -> ContactHeader.frame(header.getValue()));
framers.put(ContentTypeHeader.NAME, header -> ContentTypeHeader.frame(header.getValue()));
framers.put(ContentTypeHeader.COMPACT_NAME, header -> ContentTypeHeader.frame(header.getValue()));
framers.put(ContentLengthHeader.NAME, header -> ContentLengthHeader.frame(header.getValue()));
framers.put(ContentLengthHeader.COMPACT_NAME, header -> ContentLengthHeader.frame(header.getValue()));
framers.put(CSeqHeader.NAME, header -> CSeqHeader.frame(header.getValue()));
framers.put(ExpiresHeader.NAME, header -> ExpiresHeader.frame(header.getValue()));
framers.put(FromHeader.NAME, header -> FromHeader.frame(header.getValue()));
framers.put(FromHeader.COMPACT_NAME, header -> FromHeader.frame(header.getValue()));
framers.put(MaxForwardsHeader.NAME, header -> MaxForwardsHeader.frame(header.getValue()));
framers.put(RecordRouteHeader.NAME, header -> RecordRouteHeader.frame(header.getValue()));
framers.put(RouteHeader.NAME, header -> RouteHeader.frame(header.getValue()));
framers.put(ToHeader.NAME, header -> ToHeader.frame(header.getValue()));
framers.put(ToHeader.COMPACT_NAME, header -> ToHeader.frame(header.getValue()));
framers.put(ViaHeader.NAME, header -> ViaHeader.frame(header.getValue()));
framers.put(ViaHeader.COMPACT_NAME, header -> ViaHeader.frame(header.getValue()));
}
/**
* For the given header name, return a function that will convert a generic header instance
* into one with the correct subtype.
*/
public static Function getFramer(final Buffer b) {
// For headers that have the expected capitalization, do a quick case-sensitive
// search. If that fails do a slower case-insensitive search.
final Function framer = framers.get(b);
if (framer != null) {
return framer;
}
for (final Map.Entry> entry : framers.entrySet()) {
if (entry.getKey().equalsIgnoreCase(b)) {
return entry.getValue();
}
}
return null;
}
// ----------------------------------------------------------------------
// ----------------------------------------------------------------------
// -------- Expect methods expects something to be true and if not ------
// -------- they will throw an exception of some sort -------------------
// ----------------------------------------------------------------------
// ----------------------------------------------------------------------
/**
* Expect that the next set of bytes is "SIP/2.0" and if not then we will
* throw a {@link SipParseException}
*
* @param buffer
*/
public static void expectSIP2_0(final Buffer buffer) throws SipParseException {
expect(buffer, 'S');
expect(buffer, 'I');
expect(buffer, 'P');
expect(buffer, '/');
expect(buffer, '2');
expect(buffer, '.');
expect(buffer, '0');
}
/**
*
* @return
*/
public static Buffer expectMethod(final Buffer buffer) {
return null;
}
/**
* Check whether the buffer is exactly three bytes long and has the bytes "UDP" in it.
*
* @param t
* @return
*/
public static boolean isUDP(final Buffer t) {
try {
return t.capacity() == 3 && t.getByte(0) == 'U' && t.getByte(1) == 'D' && t.getByte(2) == 'P';
} catch (final IOException e) {
return false;
}
}
public static boolean isTCP(final Buffer t) {
try {
return t.capacity() == 3 && t.getByte(0) == 'T' && t.getByte(1) == 'C' && t.getByte(2) == 'P';
} catch (final IOException e) {
return false;
}
}
public static boolean isTLS(final Buffer t) {
try {
return t.capacity() == 3 && t.getByte(0) == 'T' && t.getByte(1) == 'L' && t.getByte(2) == 'S';
} catch (final IOException e) {
return false;
}
}
public static boolean isWS(final Buffer t) {
try {
return t.capacity() == 2 && t.getByte(0) == 'W' && t.getByte(1) == 'S';
} catch (final IOException e) {
return false;
}
}
public static boolean isWSS(final Buffer t) {
try {
return t.capacity() == 3 && t.getByte(0) == 'W' && t.getByte(1) == 'S' && t.getByte(2) == 'S';
} catch (final IOException e) {
return false;
}
}
public static boolean isSCTP(final Buffer t) {
try {
return t.capacity() == 4 && t.getByte(0) == 'S' && t.getByte(1) == 'C' && t.getByte(2) == 'T'
&& t.getByte(3) == 'P';
} catch (final IOException e) {
return false;
}
}
/**
* Check whether the buffer is exactly three bytes long and has the
* bytes "udp" in it. Note, in SIP there is a different between transport
* specified in a Via-header and a transport-param specified in a SIP URI.
* One is upper case, one is lower case. Another really annoying thing
* with SIP.
*
* @param t
* @return
*/
public static boolean isUDPLower(final Buffer t) {
try {
return t.capacity() == 3 && t.getByte(0) == 'u' && t.getByte(1) == 'd' && t.getByte(2) == 'p';
} catch (final IOException e) {
return false;
}
}
public static boolean isTCPLower(final Buffer t) {
try {
return t.capacity() == 3 && t.getByte(0) == 't' && t.getByte(1) == 'c' && t.getByte(2) == 'p';
} catch (final IOException e) {
return false;
}
}
public static boolean isTLSLower(final Buffer t) {
try {
return t.capacity() == 3 && t.getByte(0) == 't' && t.getByte(1) == 'l' && t.getByte(2) == 's';
} catch (final IOException e) {
return false;
}
}
public static boolean isWSLower(final Buffer t) {
try {
return t.capacity() == 2 && t.getByte(0) == 'w' && t.getByte(1) == 's';
} catch (final IOException e) {
return false;
}
}
public static boolean isWSSLower(final Buffer t) {
try {
return t.capacity() == 3 && t.getByte(0) == 'w' && t.getByte(1) == 's' && t.getByte(2) == 's';
} catch (final IOException e) {
return false;
}
}
public static boolean isSCTPLower(final Buffer t) {
try {
return t.capacity() == 4 && t.getByte(0) == 's' && t.getByte(1) == 'c' && t.getByte(2) == 't'
&& t.getByte(3) == 'p';
} catch (final IOException e) {
return false;
}
}
public static void expectTel(final Buffer buffer) throws SipParseException, IOException {
expect(buffer, 't');
expect(buffer, 'e');
expect(buffer, 'l');
expect(buffer, SipParser.COLON);
}
public static boolean isSips(final Buffer buffer) throws SipParseException, IndexOutOfBoundsException, IOException {
SipParser.expect(buffer, 's');
SipParser.expect(buffer, 'i');
SipParser.expect(buffer, 'p');
final byte b = buffer.readByte();
if (b == SipParser.COLON) {
return false;
}
if (b != 's') {
throw new SipParseException(buffer.getReaderIndex() - 1,
"Expected 's' since the only schemes accepted are \"sip\" and \"sips\"");
}
SipParser.expect(buffer, SipParser.COLON);
return true;
}
/**
* Consumes all generic-params it can find. If there are no generic params
* to be consumed it will return an empty list. The list of generic-params
* are found on many SIP headers such as the To, From etc. In general, the
* BNF looks like so:
*
*
*
* *( SEMI generic-param )
*
*
* E.g. in To:
*
*
* To = ( "To" / "t" ) HCOLON ( name-addr / addr-spec ) *( SEMI to-param )
* to-param = tag-param / generic-param
*
*
* @param buffer
* @return
* @throws IOException
* @throws IndexOutOfBoundsException
*/
public static List consumeGenericParams(final Buffer buffer) throws IndexOutOfBoundsException,
IOException {
final List params = new ArrayList();
while (buffer.hasReadableBytes() && buffer.peekByte() == SEMI) {
buffer.readByte(); // consume the SEMI
params.add(consumeGenericParam(buffer));
}
return params;
}
/**
* Consumes a generic param, which according to RFC 3261 section 25.1 is:
*
*
* generic-param = token [ EQUAL gen-value ]
* gen-value = token / host / quoted-string
*
*
* The return value is two buffers returned as an array and if the second
* element is null (so make sure you check it!) then there was no value for
* this parameter.
*
* Also note that due to poor implementations out there, the following is
* accepted as valid input:
*
* foo=
*
* I.e., foo is a flag parameter and as such there should not be an equal
* sign following it but there are many servers out there that does this
* anyway.
*
* @param buffer
* the buffer from which we will consume a generic-param
* @return a buffer array of size two. The first element is the name of the
* parameter and the second element is the value of that parameter
* or null if the parameter was a flag parameter (didn't have a
* value)
* @throws IOException
* @throws IndexOutOfBoundsException
*/
public static Buffer[] consumeGenericParam(final Buffer buffer) throws IndexOutOfBoundsException, IOException {
final Buffer key = consumeToken(buffer);
Buffer value = null;
if (key == null) {
return new Buffer[2];
}
if (consumeEQUAL(buffer) > 0) {
// TODO: consume host and quoted string
if (isNext(buffer, DOUBLE_QOUTE)) {
value = consumeQuotedString(buffer);
} else {
value = consumeToken(buffer);
}
}
return new Buffer[]{
key, value};
}
/**
* Will check whether the next readable byte in the buffer is a certain byte
*
* @param buffer
* the buffer to peek into
* @param b
* the byte we are checking is the next byte in the buffer to be
* read
* @return true if the next byte to read indeed is what we hope it is
*/
public static boolean isNext(final Buffer buffer, final byte b) throws IOException {
if (buffer.hasReadableBytes()) {
final byte actual = buffer.peekByte();
return actual == b;
}
return false;
}
/**
* Check whether the next byte is a digit or not
*
* @param buffer
* @retur
* @throws IOException
* @throws IndexOutOfBoundsException
*/
public static boolean isNextDigit(final Buffer buffer) throws IndexOutOfBoundsException, IOException {
if (buffer.hasReadableBytes()) {
final char next = (char) buffer.peekByte();
return next >= 48 && next <= 57;
}
return false;
}
/**
* Will expect at least 1 digit and will continue consuming bytes until a
* non-digit is encountered
*
* @param buffer
* the buffer to consume the digits from
* @return the buffer containing digits only
* @throws SipParseException
* in case there is not one digit at the first position in the
* buffer (where the current reader index is pointing to)
* @throws IOException
* @throws IndexOutOfBoundsException
*/
public static Buffer expectDigit(final Buffer buffer) throws SipParseException {
final int start = buffer.getReaderIndex();
try {
while (buffer.hasReadableBytes() && isNextDigit(buffer)) {
// consume it
buffer.readByte();
}
if (start == buffer.getReaderIndex()) {
throw new SipParseException(start, "Expected digit");
}
return buffer.slice(start, buffer.getReaderIndex());
} catch (final IndexOutOfBoundsException e) {
throw new SipParseException(start, "Expected digit but no more bytes to read");
} catch (final IOException e) {
throw new SipParseException(start, "Expected digit unable to read from underlying stream");
}
}
/**
* Convenience method for expecting (and consuming) a HCOLON, which is
* defined as:
*
* HCOLON = *( SP / HTAB ) ":" SWS
*
* See RFC3261 section 25.1 Basic Rules
*/
public static int expectHCOLON(final Buffer buffer) throws SipParseException {
final int consumed = expectHCOLONStreamFriendly(buffer);
if (consumed == -1) {
// -1 means we ran out of bytes in the stream but in those
// cases where we are not really dealing with a stream we
// would expect an IndexOutOfBoundsException so let's make
// sure to still honor that...
throw new IndexOutOfBoundsException();
}
return consumed;
}
/**
* A problem with stream based protocols is that you don't have everything
* available right away so e.g. when expecting HCOLON you may consume white spaces
* but then you run out of bytes because you haven't received them yet
* so therefore the expect(buffer, COLON) will blow up for the wrong reasons.
* It may very well be that the next byte on the wire is indeed a ':' and as
* such you should rather signal that you didn't have enough bytes to do your
* job. This one does that.
*
* Note, still some issues with this one though. Let's say the header
* we are trying to parse is "X-Hello : whatever" and we have
* only received "X-Hello :" so far. So first off we consume "X-Hello"
* then call this method, which will consume " :" but ideally we also
* want to consume the white space after the colon. I.e., when we
* go off and consume the value of this header we will end up with
* white space which normally should have been consumed by this method.
*
* Hence, whenever dealing with streams you will run into this issue
* and will have to keep extra state around to solve it. See the
* {@link SipMessageStreamBuilder} for how it is dealing with this.
*
* @param buffer
* @return
* @throws SipParseException
*/
public static int expectHCOLONStreamFriendly(final Buffer buffer) throws SipParseException {
try {
int consumed = consumeWS(buffer);
if (buffer.hasReadableBytes()) {
expect(buffer, COLON);
} else {
// normally the expect(buffer, COLON) would have thrown
// an IndexOutOfBoundsException but let's signal that as
// -1
return -1;
}
++consumed;
consumed += consumeSWSAfterHColon(buffer);
return consumed;
} catch (final IOException e) {
throw new SipParseException(buffer.getReaderIndex(), UNABLE_TO_READ_FROM_STREAM, e);
}
}
public static int consumeSWSAfterHColon(final Buffer buffer) throws IOException {
// Part of the fix for empty header values. Which based on the BNF I don't
// think is legal but it is certainly happening in the wild
// so need to accept it.
int consumed = consumeWS(buffer);
if (!isNext(buffer, CR)) {
consumed += consumeSWS(buffer);
}
return consumed;
}
/**
* Convenience method for expecting (and consuming) a SLASH, which is
* defined as:
*
*
* See RFC3261 section 25.1 Basic Rules
*
* @param buffer
* @throws SipParseException
*/
public static void expectSLASH(final Buffer buffer) throws SipParseException {
try {
final int count = consumeSLASH(buffer);
if (count == 0) {
throw new SipParseException(buffer.getReaderIndex(), "Expected SLASH");
}
} catch (final IndexOutOfBoundsException e) {
throw new SipParseException(buffer.getReaderIndex(), "Expected SLASH but nothing more to read", e);
} catch (final IOException e) {
throw new SipParseException(buffer.getReaderIndex(), "Expected SLASH but problem reading from stream", e);
}
}
/**
* Consume an slash (SLASH), which according to RFC3261 section 25.1 Basic
* Rules is:
*
* SLASH = SWS "/" SWS ; slash
*
* @param buffer
* @return true if we indeed did consume a SLASH
* @throws IOException
* @throws IndexOutOfBoundsException
*/
public static int consumeSLASH(final Buffer buffer) throws SipParseException, IndexOutOfBoundsException,
IOException {
return consumeSeparator(buffer, SLASH);
}
/**
* Expect the next byte to be a white space
*
* @param buffer
*/
public static int expectWS(final Buffer buffer) throws SipParseException {
int consumed = 0;
try {
if (buffer.hasReadableBytes()) {
final byte b = buffer.getByte(buffer.getReaderIndex());
if (b == SP || b == HTAB) {
// ok, it was a WS so consume the byte
buffer.readByte();
++consumed;
} else {
throw new SipParseException(buffer.getReaderIndex(), "Expected WS");
}
} else {
throw new SipParseException(buffer.getReaderIndex(),
"Expected WS but nothing more to read in the buffer");
}
} catch (final IOException e) {
throw new SipParseException(buffer.getReaderIndex(), UNABLE_TO_READ_FROM_STREAM, e);
}
return consumed;
}
/**
* Consume sep (separating?) whitespace (LWS), which according to RFC3261
* section 25.1 Basic Rules is:
*
* SWS = [LWS] ; sep whitespace
*
* "The SWS construct is used when linear white space is optional, generally
* between tokens and separators." (RFC3261)
*
* @param buffer
* @return
*/
public static int consumeSWS(final Buffer buffer) {
try {
return consumeLWS(buffer);
} catch (final SipParseException e) {
// ignore since currently the consumeLWS will ONLY
// throw this exception when it expected a WS at a
// particular place and since SWS is all optional
// we will silently just consume it, but return
// false however
return 0;
}
}
/**
* Consume an asterisk/star (STAR), which according to RFC3261 section 25.1
* Basic Rules is:
*
* STAR = SWS "*" SWS ; asterisk
*
* @param buffer
* @return true if we indeed did consume a STAR
* @throws IOException
* @throws IndexOutOfBoundsException
*/
public static int consumeSTAR(final Buffer buffer) throws SipParseException, IndexOutOfBoundsException,
IOException {
return consumeSeparator(buffer, STAR);
}
/**
* Consume equal sign (EQUAL), which according to RFC3261 section 25.1 Basic
* Rules is:
*
* EQUAL = SWS "=" SWS ; equal
*
* @param buffer
* @return
* @throws IOException
* @throws IndexOutOfBoundsException
*/
public static int consumeEQUAL(final Buffer buffer) throws IndexOutOfBoundsException, IOException {
return consumeSeparator(buffer, EQ);
}
/**
* Consume left parenthesis (LPAREN), which according to RFC3261 section
* 25.1 Basic Rules is:
*
* LPAREN = SWS "(" SWS ; left parenthesis
*
* @param buffer
* @return
* @throws IOException
* @throws IndexOutOfBoundsException
*/
public static int consumeLPAREN(final Buffer buffer) throws IndexOutOfBoundsException, IOException {
return consumeSeparator(buffer, LPAREN);
}
/**
* Consume right parenthesis (RPAREN), which according to RFC3261 section
* 25.1 Basic Rules is:
*
* RPAREN = SWS ")" SWS ; right parenthesis
*
* @param buffer
* @return
* @throws IOException
* @throws IndexOutOfBoundsException
*/
public static int consumeRPAREN(final Buffer buffer) throws IndexOutOfBoundsException, IOException {
return consumeSeparator(buffer, RPAREN);
}
/**
* Consume right angle quote (RAQUOT), which according to RFC3261 section
* 25.1 Basic Rules is:
*
* RAQUOT = SWS ">"; left angle quote
*
* @param buffer
* @return
* @throws IOException
* @throws IndexOutOfBoundsException
*/
public static int consumeRAQUOT(final Buffer buffer) throws IndexOutOfBoundsException, IOException {
return consumeSeparator(buffer, RAQUOT);
}
/**
* Consume left angle quote (LAQUOT), which according to RFC3261 section
* 25.1 Basic Rules is:
*
* LAQUOT = SWS "<"; left angle quote
*
* @param buffer
* @return
* @throws IOException
* @throws IndexOutOfBoundsException
*/
public static int consumeLAQUOT(final Buffer buffer) throws IndexOutOfBoundsException, IOException {
return consumeSeparator(buffer, LAQUOT);
}
/**
* Consume comma (COMMA), which according to RFC3261 section 25.1 Basic
* Rules is:
*
* COMMA = SWS "," SWS ; comma
*
* @param buffer
* @return true if we indeed did consume a COMMA
* @throws IOException
* @throws IndexOutOfBoundsException
*/
public static int consumeCOMMA(final Buffer buffer) throws SipParseException, IndexOutOfBoundsException,
IOException {
return consumeSeparator(buffer, COMMA);
}
/**
* Consume semicolon (SEMI), which according to RFC3261 section 25.1 Basic
* Rules is:
*
* SEMI = SWS ";" SWS ; semicolon
*
* @param buffer
* @return true if we indeed did consume a SEMI
* @throws IOException
* @throws IndexOutOfBoundsException
*/
public static int consumeSEMI(final Buffer buffer) throws SipParseException, IndexOutOfBoundsException,
IOException {
return consumeSeparator(buffer, SEMI);
}
/**
* Consume colon (COLON), which according to RFC3261 section 25.1 Basic
* Rules is:
*
* COLON = SWS ":" SWS ; colon
*
* @param buffer
* @return true if we indeed did consume a COLON
* @throws IOException
* @throws IndexOutOfBoundsException
*/
public static int consumeCOLON(final Buffer buffer) throws SipParseException, IndexOutOfBoundsException,
IOException {
return consumeSeparator(buffer, COLON);
}
/**
* Consume open double quotation mark (LDQUT), which according to RFC3261
* section 25.1 Basic Rules is:
*
* LDQUOT = SWS DQUOTE; open double quotation mark
*
* @param buffer
* @return true if we indeed did consume a LDQUOT
* @throws IOException
* @throws IndexOutOfBoundsException
*/
public static int consumeLDQUOT(final Buffer buffer) throws SipParseException, IndexOutOfBoundsException,
IOException {
buffer.markReaderIndex();
int consumed = consumeSWS(buffer);
if (isNext(buffer, DQUOT)) {
buffer.readByte();
++consumed;
} else {
buffer.resetReaderIndex();
return 0;
}
return consumed;
}
/**
* Consume close double quotation mark (RDQUT), which according to RFC3261
* section 25.1 Basic Rules is:
*
* RDQUOT = DQUOTE SWS ; close double quotation mark
*
* @param buffer
* @return true if we indeed did consume a LDQUOT
* @throws IOException
* @throws IndexOutOfBoundsException
*/
public static int consumeRDQUOT(final Buffer buffer) throws SipParseException, IndexOutOfBoundsException,
IOException {
buffer.markReaderIndex();
int consumed = 0;
if (isNext(buffer, DQUOT)) {
buffer.readByte();
++consumed;
} else {
buffer.resetReaderIndex();
return 0;
}
consumed += consumeSWS(buffer);
return consumed;
}
/**
* Helper function for checking stuff as described below. It is all the same pattern so...
* (from rfc 3261 section 25.1)
*
* When tokens are used or separators are used between elements,
* whitespace is often allowed before or after these characters:
*
* STAR = SWS "*" SWS ; asterisk
* SLASH = SWS "/" SWS ; slash
* EQUAL = SWS "=" SWS ; equal
* LPAREN = SWS "(" SWS ; left parenthesis
* RPAREN = SWS ")" SWS ; right parenthesis
* RAQUOT = ">" SWS ; right angle quote
* LAQUOT = SWS "<"; left angle quote
* COMMA = SWS "," SWS ; comma
* SEMI = SWS ";" SWS ; semicolon
* COLON = SWS ":" SWS ; colon
* LDQUOT = SWS DQUOTE; open double quotation mark
* RDQUOT = DQUOTE SWS ; close double quotation mark
* @param buffer
* @param b
* @return the number of bytes that was consumed.
* @throws IOException
* @throws IndexOutOfBoundsException
*/
private static int consumeSeparator(final Buffer buffer, final byte b) throws IndexOutOfBoundsException,
IOException {
buffer.markReaderIndex();
int consumed = consumeSWS(buffer);
if (isNext(buffer, b)) {
buffer.readByte();
++consumed;
} else {
buffer.resetReaderIndex();
return 0;
}
consumed += consumeSWS(buffer);
return consumed;
}
/**
* Expects a token, which according to RFC3261 section 25.1 Basic Rules is:
*
* token = 1*(alphanum / "-" / "." / "!" / "%" / "*" / "_" / "+" / "`" / "'"
* / "~" )
*
* @param buffer
* @return the buffer containing the expected token
* @throws IOException
* @throws IndexOutOfBoundsException
* @throws SipParseException
* in case there is no token
*/
public static Buffer expectToken(final Buffer buffer) throws IndexOutOfBoundsException, IOException,
SipParseException {
final Buffer token = consumeToken(buffer);
if (token == null) {
throw new SipParseException(buffer.getReaderIndex(), "Expected TOKEN");
}
return token;
}
/**
* Consumes a quoted-string, which is defined as:
*
*
* quoted-string = SWS DQUOTE *(qdtext / quoted-pair ) DQUOTE
* qdtext = LWS / %x21 / %x23-5B / %x5D-7E / UTF8-NONASCII
* quoted-pair = "\" (%x00-09 / %x0B-0C / %x0E-7F)
*
*
* Note, this is a somewhat simplified version and we'll
*
* @param buffer
* @return
* @throws IOException
* @throws SipParseException
*/
public static Buffer consumeQuotedString(final Buffer buffer) throws SipParseException, IOException {
final int start = buffer.getReaderIndex();
expect(buffer, DQUOT);
while (buffer.hasReadableBytes()) {
final byte b = buffer.readByte();
if (b == DQUOT) {
break;
} else if (b == BACK_SLASH) {
buffer.readByte();
}
}
final int stop = buffer.getReaderIndex();
buffer.setReaderIndex(start + 1);
final Buffer result = buffer.readBytes(stop - start - 2);
buffer.setReaderIndex(stop);
return result;
}
/**
* The display name in SIP is a little tricky since it may or may not be
* there and the stuff following it (whether or not it was there to begin
* with) can easily be confused with being a display name.
*
* Note, a display name in SIP is only part of of the "name-addr" construct
* and this function assumes that (even though it actually would work like a
* regular {@link #consumeToken(Buffer)} in some cases)
*
*
* name-addr = [ display-name ] LAQUOT addr-spec RAQUOT
* display-name = *(token LWS)/ quoted-string
*
*
* @param buffer
* @return the display name or null if there was none
* @throws IOException
* @throws SipParseException
*/
public static Buffer consumeDisplayName(final Buffer buffer) throws IOException, SipParseException {
if (isNext(buffer, DQUOT)) {
return consumeQuotedString(buffer);
}
final int count = getTokenCount(buffer);
if (count == 0) {
return Buffers.EMPTY_BUFFER;
}
// now, if the next thing after the count is a ':' then
// we mistook the scheme for a token so bail out.
buffer.markReaderIndex();
final Buffer potentialDisplayName = buffer.readBytes(count);
if (isNext(buffer, COLON)) {
buffer.resetReaderIndex();
return Buffers.EMPTY_BUFFER;
}
// all good...
return potentialDisplayName;
}
public static Buffer consumeAddressSpec(final Buffer buffer) throws IndexOutOfBoundsException, IOException,
SipParseException {
return consumeAddressSpec(false, buffer);
}
/**
* Consumes addr-spec, which according to RFC3261 section 25.1 is:
*
*
* addr-spec = SIP-URI / SIPS-URI / absoluteURI
* SIP-URI = "sip:" [ userinfo ] hostport
* uri-parameters [ headers ]
* SIPS-URI = "sips:" [ userinfo ] hostport
* uri-parameters [ headers ]
*
* absoluteURI = scheme ":" ( hier-part / opaque-part )
*
*
* And as you can see, it gets complicated. Also, these consume-functions
* are not to validate the exact grammar but rather to find the boundaries
* so the strategy for consuming the addr-spec is:
*
* - If '>' is encountered, then we assume that this addr-spec is within a
* name-addr so we stop here
* - If a white space or end-of-line is encountered, we also assume we are
* done UNLESS the calling code knows that we are in a protected "< >" then
* we should allow for white space. See issue-106
*
*
*
* Because of issue-106 the isProtected
* boolean was introduced to allow for spaces after the initial ";' when we know the entire
* addr-spec is e.g. "protected" inside of angle brackets "< >", which is often the case
* when we parse out a name-addr, as we do in {@link io.pkts.packet.sip.address.Address#frame(Buffer)}.
*
*
* @return
* @throws IOException
* @throws IndexOutOfBoundsException
* @throws SipParseException in case we cannot successfully frame the addr-spec.
*/
public static Buffer consumeAddressSpec(final boolean isProtected, final Buffer buffer) throws IndexOutOfBoundsException, IOException,
SipParseException {
final int startIndex = buffer.getReaderIndex();
int count = 0;
int state = 0; // zero is to look for colon, everything else is to find the end
boolean done = false;
while (buffer.hasReadableBytes() && !done) {
++count;
final byte b = buffer.readByte();
// emergency breaks...
if (state == 0 && count > 99) {
throw new SipParseException(buffer.getReaderIndex(), "No scheme found after 100 bytes, giving up");
} else if (count > MAX_LOOK_AHEAD) {
throw new SipParseException(buffer.getReaderIndex(),
"Have not been able to find the entire addr-spec after " + count + " bytes, giving up");
} else if (state == 0 && b == COLON) {
state = 1;
} else if (state == 1 && (b == RAQUOT || b == CR || b == LF)) {
done = true;
--count;
} else if (!isProtected && state == 1 && (b == SP || b == HTAB)) {
// https://github.com/aboutsip/pkts/issues/106
done = true;
--count;
}
}
buffer.setReaderIndex(startIndex);
// didn't find the scheme portion
if (state == 0) {
throw new SipParseException(buffer.getReaderIndex(), "No scheme found");
}
if (count > 0) {
return buffer.readBytes(count);
}
return null;
}
/**
* Consume the userinfo and hostport.
*
* The reason why this method does both is because the userinfo portion is
* optional and as such you actually don't know whether the stuff you are
* currently going over is the hostport or the userinfo. Also, unfortunately
* the userinfo is allowed to have characters that normally are reserved
* (such as ';'), which complicates things as well.
*
*
*
* SIP-URI = "sip:" [ userinfo ] hostport
* uri-parameters [ headers ]
* SIPS-URI = "sips:" [ userinfo ] hostport
* uri-parameters [ headers ]
*
* userinfo = ( user / telephone-subscriber ) [ ":" password ] "@"
* user = 1*( unreserved / escaped / user-unreserved )
* user-unreserved = "&" / "=" / "+" / "$" / "," / ";" / "?" / "/"
* password = *( unreserved / escaped / "&" / "=" / "+" / "$" / "," )
* hostport = host [ ":" port ]
*
*
* As you can see, the user-unreserved is what mess things up. it would have
* been way easier and more efficient if the user-unreserved wasn't there...
*
* @param buffer
* @return
*/
public static SipUserHostInfo consumeUserInfoHostPort(final Buffer buffer) throws SipParseException, IOException {
return SipUserHostInfo.frame(buffer);
}
/**
* Consume the "sent-protocol", which according to RFC 3261 is:
*
*
* sent-protocol = protocol-name SLASH protocol-version SLASH transport
* transport = "UDP" / "TCP" / "TLS" / "SCTP" / other-transport
* other-transport = token
*
*
* The "sent-protocol" is only present in a Via header and typically looks
* like this: SIP/2.0/UDP
*
* The consume method will make sure that "SIP/2.0/" is present and if not,
* complain. The transport can really be anything and as such that is what
* you will get back as a return value. Hence, in the above example you
* would get back a buffer consisting of "UDP".
*
* Also note that the transport can be "other-transport" which translates to
* a "token" so we allow really anything and as such we will just consume
* and return the token after verifying that it start with the SIP/2.0
* stuff.
*
* @param buffer
* @return the transport part of the "sent-protocol". Typically this will be
* one of UDP, TCP or TLS.
* @throws IOException
* @throws SipParseException
* in case anything goes wrong while parsing including if the
* protocol-name isn't SIP and the version isn't 2.0
*/
public static Buffer consumeSentProtocol(final Buffer buffer) throws IOException, SipParseException {
expectSIP2_0(buffer);
expect(buffer, SipParser.SLASH);
final Buffer protocol = consumeToken(buffer);
if (protocol == null || protocol.isEmpty()) {
throw new SipParseException(buffer.getReaderIndex(), "Expected transport");
}
return protocol;
}
/**
* Consume a token, which according to RFC3261 section 25.1 Basic Rules is:
*
* token = 1*(alphanum / "-" / "." / "!" / "%" / "*" / "_" / "+" / "`" / "'"
* / "~" )
*
* @param buffer
* @return the buffer containing the token we consumed or null if nothing
* was consumed.
* @throws IOException
* @throws IndexOutOfBoundsException
*/
public static Buffer consumeToken(final Buffer buffer) throws IndexOutOfBoundsException, IOException {
final int count = getTokenCount(buffer);
if (count == 0) {
return null;
}
return buffer.readBytes(count);
}
/**
* Consumes a alphanum.
*
* @param buffer
* @return
* @throws IOException
*/
public static Buffer consumeAlphaNum(final Buffer buffer) throws IOException {
final int count = getAlphaNumCount(buffer);
if (count == 0) {
return null;
}
return buffer.readBytes(count);
}
/**
* Consume a Via-header, which according to RFC3261 is:
*
*
* Via = ( "Via" / "v" ) HCOLON via-parm *(COMMA via-parm)
* via-parm = sent-protocol LWS sent-by *( SEMI via-params )
* via-params = via-ttl / via-maddr / via-received / via-branch / via-extension
* via-ttl = "ttl" EQUAL ttl
* via-maddr = "maddr" EQUAL host
* via-received = "received" EQUAL (IPv4address / IPv6address)
* via-branch = "branch" EQUAL token
* via-extension = generic-param
* sent-protocol = protocol-name SLASH protocol-version SLASH transport
*
*
* Note, this method assumes that you have already stripped off the "Via" or
* "v". I.e., the header name.
*
* The return value is ALWAYS an array of objects of size 4. However, the
* port can be null (index 2 = the third value) so make sure to check it.
* Also, the 4th value (index 3) contains a List containing all
* the via-parameters. Each entry in the list is a two dimensional array
* where the first element is the key and the second is the value. For flag
* parameters, the value will be null so make sure to check. For more info
* regarding how parameters are parsed, see
* {@link #consumeGenericParams(Buffer)}.
*
*
* - result[0] - the protocol. Will never ever be null
* - result[1] - the sent-by host. Will never ever be null
* - result[2] - the sent-by port. May be null if port wasn't specified
* - result[3] - the via-parameters as a List
. Will always have
* elements in it since a via without a branch parameter is illegal.
*
*
* @param buffer
* @return returns an array of 4 elements. See above for details
* @throws SipParseException
* @throws IOException
*/
public static Object[] consumeVia(final Buffer buffer) throws SipParseException, IOException {
final Object[] result = new Object[4];
// start off by just finding the ';'. A Via-header MUST have a branch
// parameter and as such
// there must be a ';' present. If there isn't one, then bail out and
// complain.
int count = 0;
int indexOfSemi = 0;
int countOfColons = 0;
int indexOfLastColon = 0;
int readerIndexOfLastColon = 0; // for reporting
consumeSWS(buffer);
result[0] = consumeSentProtocol(buffer);
consumeLWS(buffer);
final int index = buffer.getReaderIndex();
while (indexOfSemi == 0 && buffer.hasReadableBytes() && ++count < MAX_LOOK_AHEAD) {
final byte b = buffer.readByte();
if (b == SipParser.SEMI) {
indexOfSemi = count;
} else if (b == SipParser.COLON) {
++countOfColons;
indexOfLastColon = count;
readerIndexOfLastColon = buffer.getReaderIndex();
}
}
if (count == 0) {
return null;
}
if (count == MAX_LOOK_AHEAD) {
throw new SipParseException(buffer.getReaderIndex(),
"Unable to find the parameters part of the Via-header "
+ "even after searching for " + MAX_LOOK_AHEAD + " bytes.");
}
if (indexOfSemi == 0) {
// well, we don't check if the branch parameter is there but
// if there are no parameters present at all then there
// is no chance of it being present.
throw new SipParseException(buffer.getReaderIndex(),
"No via-parameters found. The Via-header MUST contain at least the branch parameter.");
}
buffer.setReaderIndex(index);
if (countOfColons == 0 || countOfColons == 7) {
// no port, just host
result[1] = buffer.readBytes(indexOfSemi - 1);
} else if (indexOfLastColon != 0 && (countOfColons == 1 || countOfColons == 8)) {
// found either a single colon or 8 colons where 8 colons indicates
// that we have an ipv6 address in front of us.
result[1] = buffer.readBytes(indexOfLastColon - 1);
buffer.readByte(); // consume ':'
result[2] = buffer.readBytes(indexOfSemi - indexOfLastColon - 1); // consume
// port
if (result[2] == null || ((Buffer) result[2]).isEmpty()) {
throw new SipParseException(readerIndexOfLastColon + 1, "Expected port after colon");
}
} else {
// indication an strange number of colons. May be the strange
// ipv4 address after ipv6 thing which we currently dont handle
throw new SipParseException(indexOfLastColon, "Found " + countOfColons + " which seems odd."
+ " Expecting 0, 1, 7 or 8 colons in the Via-host:port portion. Please check your traffic");
}
final List params = consumeGenericParams(buffer);
result[3] = params;
return result;
}
/**
* Consume a sent-by which according to 3261 is:
*
*
* sent-by = host [ COLON port ]
* host = hostname / IPv4address / IPv6reference
* hostname = *( domainlabel "." ) toplabel [ "." ]
* domainlabel = alphanum
* toplabel = ALPHA / ALPHA *( alphanum / "-" ) alphanum
* IPv4address = 1*3DIGIT "." 1*3DIGIT "." 1*3DIGIT "." 1*3DIGIT
* IPv6reference = "[" IPv6address "]"
* IPv6address = hexpart [ ":" IPv4address ]
* hexpart = hexseq / hexseq "::" [ hexseq ] / "::" [ hexseq ]
* hexseq = hex4 *( ":" hex4)
* hex4 = 1*4HEXDIG
* port = 1*DIGIT
*
*
* Now, since we want to do things as fast as possible and all the
* consumeXXX methods only do framing we will implement something a little
* simpler, faster but not 100% according to the BNF.
*
* So, consume everything until we either hit a ';' signifying parameters or
* a ':' which then forces us to start checking the port. Also, white space
* will stop parsing.
*
* However, a colon could also signify an IPv6 address, which is not handled
* right now.
*
* @param buffer
* @return
* @throws IOException
*/
public static Buffer[] consumeSentBye(final Buffer buffer) throws SipParseException, IOException {
final int index = buffer.getReaderIndex();
int count = 0;
boolean done = false;
boolean firstColon = false;
boolean consumePort = false;
while (!done && buffer.hasReadableBytes()) {
final byte b = buffer.readByte();
++count;
if (firstColon && isDigit(b)) {
// get port
consumePort = true;
done = true;
count -= 2;
continue;
} else if (firstColon) {
// consume
firstColon = false;
continue;
}
if (b == SipParser.COLON) {
firstColon = true;
} else if (b == SipParser.SEMI) {
--count;
done = true;
}
}
if (count == 0) {
return null;
}
buffer.setReaderIndex(index);
final Buffer host = buffer.readBytes(count);
Buffer port = null;
if (consumePort) {
buffer.readByte(); // consume ':'
port = consumePort(buffer);
}
return new Buffer[]{
host, port};
}
/**
* Consume a port, which according to RFC 3261 is:
*
* port = 1*DIGIT
*
* @param buffer
* @return the buffer containing only digits or null if there was none fun.
* @throws IOException
*/
public static Buffer consumePort(final Buffer buffer) throws IOException {
int count = 0;
final int index = buffer.getReaderIndex();
boolean done = false;
while (!done && buffer.hasReadableBytes()) {
if (isDigit(buffer.readByte())) {
++count;
} else {
done = true;
}
}
buffer.setReaderIndex(index);
if (count != 0) {
return buffer.readBytes(count);
}
return null;
}
public static Buffer consumeHostname(final Buffer buffer) throws IOException {
return null;
}
/**
* Consume a m-type, which according to RFC3261 section 25.1 Basic Rules is:
*
*
* m-type = discrete-type / composite-type
* discrete-type = "text" / "image" / "audio" / "video" / "io.sipstack.application.application" / extension-token
* composite-type = "message" / "multipart" / extension-token
* extension-token = ietf-token / x-token
* ietf-token = token
* x-token = "x-" token
*
*
* And if you really read through all of that stuff it all boils down to
* "token" so that is all we end up doing in this method. Hence, this method
* is really only to put some context to consuming a media-type
*
* @return
* @throws IndexOutOfBoundsException
* @throws IOException
*/
public static Buffer consumeMType(final Buffer buffer) throws SipParseException {
try {
return consumeToken(buffer);
} catch (final IndexOutOfBoundsException e) {
throw new SipParseException(buffer.getReaderIndex(), "Tried to consume m-type but buffer ended abruptly", e);
} catch (final IOException e) {
throw new SipParseException(buffer.getReaderIndex(),
"Tried to consume m-type but problem reading from underlying stream", e);
}
}
/**
* Consume a m-subtype, which according to RFC3261 section 25.1 Basic Rules
* is:
*
*
* m-subtype = extension-token / iana-token
* extension-token = ietf-token / x-token
* ietf-token = token
* x-token = "x-" token
* iana-token = token
*
*
* And if you really read through all of that stuff it all boils down to
* "token" so that is all we end up doing in this method. Hence, this method
* is really only to put some context to consuming a media-type
*
* @return
* @throws IndexOutOfBoundsException
* @throws IOException
*/
public static Buffer consumeMSubtype(final Buffer buffer) throws SipParseException {
try {
return consumeToken(buffer);
} catch (final IndexOutOfBoundsException e) {
throw new SipParseException(buffer.getReaderIndex(), "Tried to consume m-type but buffer ended abruptly", e);
} catch (final IOException e) {
throw new SipParseException(buffer.getReaderIndex(),
"Tried to consume m-type but problem reading from underlying stream", e);
}
}
/**
* Helper method that counts the number of bytes that are considered part of
* the next token in the {@link Buffer}.
*
* @param buffer
* @return a count of the number of bytes the next token contains or zero if
* no token is to be found within the buffer.
* @throws IOException
* @throws IndexOutOfBoundsException
*/
public static int getTokenCount(final Buffer buffer) throws IndexOutOfBoundsException, IOException {
boolean done = false;
int count = 0;
buffer.markReaderIndex();
while (buffer.hasReadableBytes() && !done) {
final byte b = buffer.readByte();
final boolean ok = isAlphaNum(b) || b == DASH || b == PERIOD || b == EXCLAMATIONPOINT
|| b == PERCENT || b == STAR || b == UNDERSCORE || b == PLUS || b == BACKTICK
|| b == TICK || b == TILDE;
if (ok) {
++count;
} else {
done = true;
}
}
buffer.resetReaderIndex();
return count;
}
/**
* Helper method that counts the number of bytes that are considered part of
* the next alphanum block.
*
* @param buffer
* @return a count of the number of bytes the next alphaum contains or zero
* if none is found.
* @throws IndexOutOfBoundsException
* @throws IOException
*/
public static int getAlphaNumCount(final Buffer buffer) throws IndexOutOfBoundsException, IOException {
boolean done = false;
int count = 0;
final int index = buffer.getReaderIndex();
while (buffer.hasReadableBytes() && !done) {
final byte b = buffer.readByte();
if (isAlphaNum(b)) {
++count;
} else {
done = true;
}
}
buffer.setReaderIndex(index);
return count;
}
/**
* Check whether next byte is a alpha numeric one.
*
* @param buffer
* @return true if the next byte is a alpha numeric character, otherwise
* false
* @throws IOException
* @throws IndexOutOfBoundsException
*/
public static boolean isNextAlphaNum(final Buffer buffer) throws IndexOutOfBoundsException, IOException {
if (buffer.hasReadableBytes()) {
final byte b = buffer.peekByte();
return isAlphaNum(b);
}
return false;
}
/**
* Checks whether the character could be part of the host portion of a SIP URI.
*
* This does not perform an entirely robust validation as it does not operate
* with the full context of the hostname.
*
* @param ch
* @return true if the character is valid in hostnames, false otherwise
*/
public static boolean isHostPortCharacter(final char ch) {
return isAlphaNum(ch) || ch == DASH || ch == PERIOD || ch == COLON;
}
public static boolean isHostPortCharacter(final byte b) {
return isHostPortCharacter((char) b);
}
/**
* Helper method for checking whether the supplied byte is a alphanumeric
* character or not.
*
* @param b
* @return true if the byte is indeed a alphanumeric character, false
* otherwise
*/
public static boolean isAlphaNum(final char ch) {
return ch >= 97 && ch <= 122 || ch >= 48 && ch <= 57 || ch >= 65 && ch <= 90;
}
public static boolean isAlphaNum(final byte b) {
return isAlphaNum((char) b);
}
public static boolean isDigit(final char ch) {
return ch >= 48 && ch <= 57;
}
public static boolean isDigit(final byte b) {
return isDigit((char) b);
}
public static boolean isAlpha(final char ch) {
return ch >= 97 && ch <= 122 || ch >= 65 && ch <= 90;
}
public static boolean isAlpha(final byte b) {
return isAlpha((char) b);
}
/**
* Consume linear whitespace (LWS), which according to RFC3261 section 25.1
* Basic Rules is:
*
* LWS = [*WSP CRLF] 1*WSP ; linear whitespace
*
* @param buffer
* @return the number of bytes consumed
*/
public static int consumeLWS(final Buffer buffer) throws SipParseException {
final int i = buffer.getReaderIndex();
consumeWS(buffer);
// if we consume a CRLF we expect at least ONE WS to be present next
if (consumeCRLF(buffer) > 0) {
expectWS(buffer);
}
consumeWS(buffer);
if (buffer.getReaderIndex() == i) {
throw new SipParseException(i, "Expected at least 1 WSP");
}
return buffer.getReaderIndex() - i;
}
/**
* Consume CR + LF
*
* @param buffer
* @return the number of bytes we consumed, which should be two
* if we indeed consumed CRLF or zero otherwise.
*/
public static int consumeCRLF(final Buffer buffer) throws SipParseException {
try {
buffer.markReaderIndex();
final byte cr = buffer.readByte();
final byte lf = buffer.readByte();
if (cr == CR && lf == LF) {
return 2;
}
} catch (final IndexOutOfBoundsException e) {
// fall through
} catch (final IOException e) {
throw new SipParseException(buffer.getReaderIndex(), UNABLE_TO_READ_FROM_STREAM, e);
}
buffer.resetReaderIndex();
return 0;
}
/**
* Check so that the next byte in the passed in buffer is the expected one.
*
* @param buffer
* the buffer that we will check.
* @param expected
* the buffer that contains the expected byte (note, it is 1
* byte, not bytes)
* @throws ParseException
* in case the expected byte is not the next byte in the buffer
*/
public static void expect(final Buffer buffer, final byte expected) throws SipParseException, IOException {
final byte actual = buffer.readByte();
if (actual != expected) {
final String actualStr = new String(new byte[]{actual}, Charset.forName("UTF-8"));
final String expectedStr = new String(new byte[]{expected});
throw new SipParseException(buffer.getReaderIndex(), "Expected '" + expected + "' (" + expectedStr
+ ") got '" + actual + "' (" + actualStr + ")");
}
}
/**
* Consume all the whitespace we find (WS)
*
* @param buffer
* @return true if we did consume something, false otherwise
*/
public static int consumeWS(final Buffer buffer) throws SipParseException {
try {
boolean done = false;
int count = 0;
while (buffer.hasReadableBytes() && !done) {
if (isNext(buffer, SP) || isNext(buffer, HTAB)) {
buffer.readByte();
++count;
} else {
done = true;
}
}
return count;
} catch (final IOException e) {
throw new SipParseException(buffer.getReaderIndex(), UNABLE_TO_READ_FROM_STREAM, e);
}
}
/**
* Check so that the next byte in the passed in buffer is the expected one.
*
* @param buffer
* the buffer that we will check.
* @param expected
* the expected char
* @throws SipParseException
* in case the expected char is not the next char in the buffer
* or if there is an error reading from the underlying stream
*/
public static void expect(final Buffer buffer, final char ch) throws SipParseException {
try {
final int i = buffer.readUnsignedByte();
if (i != ch) {
throw new SipParseException(buffer.getReaderIndex(), "Expected '" + ch + "' got '" + i + "'");
}
} catch (final IOException e) {
throw new SipParseException(buffer.getReaderIndex(), UNABLE_TO_READ_FROM_STREAM, e);
}
}
/**
* Convenience method for slicing out the next header name but NOT checking
* if HCOLON shows up afterwards. This is useful when dealing with a stream
* of bytes coming in over the network, as in TCP, so you may actually find
* SP or HTAB but the COLON, and as such, the HCOLON, hasn't shown up yet
* so the method {@link #nextHeaderName(Buffer)} would blow up on no
* HCOLON, which is not what we want. Hence, use this method and then
* check HCOLON yourself.
*
* @param buffer
* @return
*/
public static Buffer nextHeaderNameDontCheckHColon(final Buffer buffer) {
try {
final int startIndex = buffer.getReaderIndex();
int nameIndex = 0;
while (buffer.hasReadableBytes() && nameIndex == 0) {
if (isNext(buffer, SP) || isNext(buffer, HTAB) || isNext(buffer, COLON)) {
nameIndex = buffer.getReaderIndex();
} else {
buffer.readByte();
}
}
// Bad header! No HCOLON found! (or beginning thereof anyway)
if (nameIndex == 0) {
// probably ran out of bytes to read so lets just return null
buffer.setReaderIndex(startIndex);
return null;
}
return buffer.slice(startIndex, nameIndex);
} catch (final IOException e) {
throw new SipParseException(buffer.getReaderIndex(), UNABLE_TO_READ_FROM_STREAM, e);
}
}
public static Buffer nextHeaderName(final Buffer buffer) throws SipParseException {
final Buffer name = nextHeaderNameDontCheckHColon(buffer);
if (name != null) {
expectHCOLON(buffer);
}
return name;
}
public static List nextHeaders(final Buffer buffer) throws SipParseException {
try {
final int startIndex = buffer.getReaderIndex();
int nameIndex = 0;
while (buffer.hasReadableBytes() && nameIndex == 0) {
if (isNext(buffer, SP) || isNext(buffer, HTAB) || isNext(buffer, COLON)) {
nameIndex = buffer.getReaderIndex();
} else {
buffer.readByte();
}
}
// Bad header! No HCOLON found! (or beginning thereof anyway)
if (nameIndex == 0) {
// probably ran out of bytes to read so lets just return null
return null;
}
final Buffer name = buffer.slice(startIndex, nameIndex);
expectHCOLON(buffer);
final List values = readHeaderValues(name, buffer).values;
final List headers = new ArrayList(values.size());
for (final Buffer value : values) {
headers.add(new SipHeaderImpl(name, value));
}
return headers;
} catch (final IOException e) {
throw new SipParseException(buffer.getReaderIndex(), UNABLE_TO_READ_FROM_STREAM, e);
}
}
/**
* Not all headers allow for multiple values on a single line. This is a
* basic check for validating whether or not that the header allows it or
* not. Note, for headers such as Contact, it depends!
*
* @param headerName
* @return
*/
private static boolean isHeaderAllowingMultipleValues(final Buffer headerName) {
final int size = headerName.getReadableBytes();
if (size == 7) {
return !isSubjectHeader(headerName);
} else if (size == 5) {
return !isAllowHeader(headerName);
} else if (size == 4) {
return !isDateHeader(headerName);
} else if (size == 1) {
return !isAllowEventsHeaderShort(headerName);
} else if (size == 12) {
return !isAllowEventsHeader(headerName);
}
return true;
}
/**
* The date header also allows for comma within the value of the header.
*
* @param name
* @return
*/
private static boolean isDateHeader(final Buffer name) {
try {
return name.getByte(0) == 'D' && name.getByte(1) == 'a' &&
name.getByte(2) == 't' && name.getByte(3) == 'e';
} catch (final IOException e) {
return false;
}
}
private static boolean isAllowHeader(final Buffer name) {
try {
return name.getByte(0) == 'A' && name.getByte(1) == 'l' &&
name.getByte(2) == 'l' && name.getByte(3) == 'o' &&
name.getByte(4) == 'w';
} catch (final IOException e) {
return false;
}
}
private static boolean isAllowEventsHeaderShort(final Buffer name) {
try {
return name.getByte(0) == 'u';
} catch (final IOException e) {
return false;
}
}
private static boolean isAllowEventsHeader(final Buffer name) {
try {
return name.getByte(0) == 'A' && name.getByte(1) == 'l' &&
name.getByte(2) == 'l' && name.getByte(3) == 'o' &&
name.getByte(4) == 'w' && name.getByte(5) == '-' &&
name.getByte(6) == 'E' && name.getByte(7) == 'v' &&
name.getByte(8) == 'e' && name.getByte(9) == 'n' &&
name.getByte(10) == 't' && name.getByte(11) == 's';
} catch (final IOException e) {
return false;
}
}
private static boolean isSubjectHeader(final Buffer name) {
try {
return name.getByte(0) == 'S' && name.getByte(1) == 'u' &&
name.getByte(2) == 'b' && name.getByte(3) == 'j' &&
name.getByte(4) == 'e' && name.getByte(5) == 'c' &&
name.getByte(6) == 't';
} catch (final IOException e) {
return false;
}
}
/**
* Because parsing streaming data where not everything has shown up yet we must remember
* the state of where we are in the "parse out header values".
*/
public static final class HeaderValueState {
public List values = new ArrayList<>(2);
public int start;
public int stop = -1;
public boolean foundCR = false;
public boolean foundLF = false;
public boolean foundCRLF = false;
public boolean foundComma = false;
public boolean insideQuotedString = false;
public boolean done = false;
public boolean foldedLine = false;
public HeaderValueState(final int readerIndex) {
start = readerIndex;
}
public void reset(final int readerIndex) {
start = readerIndex;
values = new ArrayList<>(2);
stop = -1;
foundCR = false;
foundLF = false;
foundCRLF = false;
foundComma = false;
insideQuotedString = false;
done = false;
foldedLine = false;
}
}
public static HeaderValueState readHeaderValues(final HeaderValueState state, final Buffer headerName, final Buffer buffer) throws IOException {
while (buffer.hasReadableBytes() && !state.done) {
final byte b = buffer.readByte();
switch (b) {
case DOUBLE_QOUTE:
state.insideQuotedString = !state.insideQuotedString;
break;
case LF:
state.foundLF = true;
state.foundCRLF = state.foundCR;
final int separatorLen = state.foundCRLF ? 2 : 1;
state.stop = buffer.getReaderIndex() - separatorLen;
break;
case CR:
state.foundCR = true;
// state.stop = buffer.getReaderIndex() - 1;
break;
case COMMA:
// if we find a comma then we may have found the end of this
// header value depending whether or not the header we are
// framing actually allows multiple values on a single line
if (!state.insideQuotedString && isHeaderAllowingMultipleValues(headerName)) {
state.stop = buffer.getReaderIndex() - 1;
buffer.setReaderIndex(state.stop);
consumeCOMMA(buffer);
state.foundComma = true;
state.foundCRLF = true;
}
break;
default:
break;
}
if (state.foundCRLF || state.foundLF) {
state.values.add(buffer.slice(state.start, state.stop));
// if (isNext(buffer, LF)) {
// buffer.readByte();
// }
// Until we have implemented the CompositeBuffer I'm just going to cheat like this
// and yes, it is stupid but folded lines aren't that common so...
if (state.foldedLine) {
final Buffer line2 = state.values.remove(state.values.size() - 1);
final Buffer line1 = state.values.remove(state.values.size() - 1);
final Buffer folded = Buffers.wrap(line1 + " " + line2);
state.values.add(folded);
state.foldedLine = false;
}
if (isNext(buffer, SP) || isNext(buffer, HTAB)) {
consumeWS(buffer);
state.foldedLine = !state.foundComma;
} else if (!state.foundComma) {
state.done = true;
}
state.foundCR = false;
state.foundLF = false;
state.foundCRLF = false;
state.foundComma = false;
state.start = buffer.getReaderIndex();
}
}
return state;
}
public static HeaderValueState readHeaderValues(final Buffer headerName, final Buffer buffer) throws IOException {
final HeaderValueState state = new HeaderValueState(buffer.getReaderIndex());
return readHeaderValues(state, headerName, buffer);
}
/**
* Get the next header, which may actually be returning multiple if there
* are multiple headers on the same line.
*
* @param buffer
* @return an array where the first element is the name of the buffer and
* the second element is the value of the buffer
* @throws SipParseException
*/
public static SipHeader nextHeader(final Buffer buffer) throws SipParseException {
try {
final int startIndex = buffer.getReaderIndex();
int nameIndex = 0;
while (buffer.hasReadableBytes() && nameIndex == 0) {
if (isNext(buffer, SP) || isNext(buffer, HTAB) || isNext(buffer, COLON)) {
nameIndex = buffer.getReaderIndex();
} else {
buffer.readByte();
}
}
// Bad header! No HCOLON found! (or beginning thereof anyway)
if (nameIndex == 0) {
// probably ran out of bytes to read so lets just return null
return null;
}
final Buffer name = buffer.slice(startIndex, nameIndex);
expectHCOLON(buffer);
// Note, we are framing headers from a sip request or response which
// is why we safely can assume that there will ALWAYS be a CRLF
// after each line
Buffer valueBuffer = buffer.readLine();
// Folded lines are rare so try and avoid the bulk of
// the work if possible.
if (isNext(buffer, SP) || isNext(buffer, HTAB)) {
List foldedLines = null;
boolean done = false;
while (!done) {
if (isNext(buffer, SP) || isNext(buffer, HTAB)) {
consumeWS(buffer);
if (foldedLines == null) {
foldedLines = new ArrayList(2);
}
foldedLines.add(buffer.readLine());
} else {
done = true;
}
}
if (foldedLines != null) {
// even though stupid, folded lines are not that common
// so optimize if this ever becomes a problem.
String stupid = valueBuffer.toString();
for (final Buffer line : foldedLines) {
stupid += " " + line.toString();
}
valueBuffer = Buffers.wrap(stupid.getBytes(Charset.forName("UTF-8")));
consumeWS(valueBuffer);
}
}
return new SipHeaderImpl(name, valueBuffer);
} catch (final IOException e) {
throw new SipParseException(buffer.getReaderIndex(), UNABLE_TO_READ_FROM_STREAM, e);
}
}
/**
* Frame the supplied buffer into a {@link SipMessage}. No deep analysis of the message will be
* performed by this framer so there is no guarantee that this {@link SipMessage} is actually a
* well formed message.
*
* @param buffer
* @return the framed {@link SipMessage}
*/
public static SipMessage frame(final Buffer buffer) throws IOException {
if (true)
return frame2(buffer);
if (!couldBeSipMessage(buffer)) {
throw new SipParseException(0, "Cannot be a SIP message because is doesnt start with \"SIP\" "
+ "(for responses) or a method (for requests)");
}
// we just assume that the initial line
// indeed is a correct sip line
final Buffer rawInitialLine = buffer.readLine();
// which means that the headers are about
// to start now.
final int startHeaders = buffer.getReaderIndex();
Buffer currentLine = null;
while ((currentLine = buffer.readLine()) != null && currentLine.hasReadableBytes()) {
// just moving along, we don't really care why
// we stop, we have found what we want anyway, which
// is the boundary between headers and the potential
// payload (or end of message)
}
final Buffer headers = buffer.slice(startHeaders, buffer.getReaderIndex());
Buffer payload = null;
if (buffer.hasReadableBytes()) {
payload = buffer.slice();
}
if (SipInitialLine.isResponseLine(rawInitialLine)) {
throw new RuntimeException("No longer using the old mutable sip messages");
// return new SipResponseImpl(rawInitialLine, headers, payload);
} else {
throw new RuntimeException("No longer using the old mutable sip messages");
// return new SipRequestImpl(rawInitialLine, headers, payload);
}
}
/**
*
* @param buffer
* @return
* @throws IOException
*/
public static SipMessage frame2(final Buffer buffer) throws IOException {
if (!couldBeSipMessage(buffer)) {
throw new SipParseException(0, "Cannot be a SIP message because is doesnt start with \"SIP\" "
+ "(for responses) or a method (for requests)");
}
final int startIndex = buffer.getReaderIndex();
final SipInitialLine initialLine = SipInitialLine.parse(buffer.readLine());
// which means that the headers are about
// to start now.
final int startHeaders = buffer.getReaderIndex();
// Move along as long as we actually can consume an header and
Buffer headerName = null;
final List headers = new ArrayList<>();
short count = 0;
int contentLength = 0;
short indexOfTo = -1;
short indexOfFrom = -1;
short indexOfCSeq = -1;
short indexOfCallId = -1;
short indexOfMaxForwards = -1;
short indexOfVia = -1;
short indexOfRoute = -1;
short indexOfRecordRoute = -1;
short indexOfContact = -1;
while (consumeCRLF(buffer) != 2 && (headerName = SipParser.nextHeaderName(buffer)) != null) {
final List values = readHeaderValues(headerName, buffer).values;
for (final Buffer value : values) {
SipHeader header = new SipHeaderImpl(headerName, value);
// The headers that are most commonly used will be fully
// parsed just because no stack can really function without
// looking into these headers.
if (header.isContentLengthHeader()) {
final ContentLengthHeader l = header.ensure().toContentLengthHeader();
contentLength = l.getContentLength();
header = l;
} else if (header.isContactHeader() && indexOfContact == -1) {
header = header.ensure();
indexOfContact = count;
} else if (header.isCSeqHeader() && indexOfCSeq == -1) {
header = header.ensure();
indexOfCSeq = count;
} else if (header.isMaxForwardsHeader() && indexOfMaxForwards == -1) {
header = header.ensure();
indexOfMaxForwards = count;
} else if (header.isFromHeader() && indexOfFrom == -1) {
header = header.ensure();
indexOfFrom = count;
} else if (header.isToHeader() && indexOfTo == -1) {
header = header.ensure();
indexOfTo = count;
} else if (header.isViaHeader() && indexOfVia == -1) {
header = header.ensure();
indexOfVia = count;
} else if (header.isCallIdHeader() && indexOfCallId == -1) {
header = header.ensure();
indexOfCallId = count;
} else if (header.isRouteHeader() && indexOfRoute == -1) {
header = header.ensure();
indexOfRoute = count;
} else if (header.isRecordRouteHeader() && indexOfRecordRoute == -1) {
header = header.ensure();
indexOfRecordRoute = count;
}
headers.add(header);
++count;
}
}
// final Buffer headers = buffer.slice(startHeaders, buffer.getReaderIndex());
Buffer payload = null;
if (contentLength > 0 && buffer.hasReadableBytes()) {
payload = buffer.readBytes(Math.min(contentLength, buffer.getReadableBytes()));
} else {
payload = Buffers.EMPTY_BUFFER;
}
// slice out the entire message from this buffer since
// everything is immutable when this message potentially
// is written to socket again, there is really nothing to do
// other than just write these bytes out.
final Buffer msg = buffer.slice(startIndex, buffer.getReaderIndex());
if (initialLine.isRequestLine()) {
return new ImmutableSipRequest(msg, initialLine.toRequestLine(), headers,
indexOfTo,
indexOfFrom,
indexOfCSeq,
indexOfCallId,
indexOfMaxForwards,
indexOfVia,
indexOfRoute,
indexOfRecordRoute,
indexOfContact,
payload);
} else {
return new ImmutableSipResponse(msg, initialLine.toResponseLine(), headers,
indexOfTo,
indexOfFrom,
indexOfCSeq,
indexOfCallId,
indexOfMaxForwards,
indexOfVia,
indexOfRoute,
indexOfRecordRoute,
indexOfContact,
payload);
}
}
/**
* Helper function that checks whether or not the data could be a SIP message. It is a very
* basic check but if it doesn't go through it definitely is not a SIP message.
*
* @param data
* @return
*/
public static boolean couldBeSipMessage(final Buffer data) throws IOException {
final byte a = data.getByte(0);
final byte b = data.getByte(1);
final byte c = data.getByte(2);
return couldBeSipMessage(a, b, c);
}
public static boolean couldBeSipMessage(final byte a, final byte b, final byte c) throws IOException {
return a == 'S' && b == 'I' && c == 'P' || // response
a == 'I' && b == 'N' && c == 'V' || // INVITE
a == 'A' && b == 'C' && c == 'K' || // ACK
a == 'B' && b == 'Y' && c == 'E' || // BYE
a == 'O' && b == 'P' && c == 'T' || // OPTIONS
a == 'C' && b == 'A' && c == 'N' || // CANCEL
a == 'M' && b == 'E' && c == 'S' || // MESSAGE
a == 'R' && b == 'E' && c == 'G' || // REGISTER
a == 'I' && b == 'N' && c == 'F' || // INFO
a == 'P' && b == 'R' && c == 'A' || // PRACK
a == 'S' && b == 'U' && c == 'B' || // SUBSCRIBE
a == 'N' && b == 'O' && c == 'T' || // NOTIFY
a == 'U' && b == 'P' && c == 'D' || // UPDATE
a == 'R' && b == 'E' && c == 'F' || // REFER
a == 'P' && b == 'U' && c == 'B'; // PUBLISH
}
}