dns_types/protocol/types.rs
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use bytes::{BufMut, Bytes, BytesMut};
use std::fmt;
use std::net::{Ipv4Addr, Ipv6Addr};
use std::str::FromStr;
/// Maximum encoded length of a domain name. The number of labels
/// plus sum of the lengths of the labels.
pub const DOMAINNAME_MAX_LEN: usize = 255;
/// Maximum length of a single label in a domain name.
pub const LABEL_MAX_LEN: usize = 63;
/// Octet mask for the QR flag being set (response).
pub const HEADER_MASK_QR: u8 = 0b1000_0000;
/// Octet mask for the opcode field.
pub const HEADER_MASK_OPCODE: u8 = 0b0111_1000;
/// Offset for the opcode field.
pub const HEADER_OFFSET_OPCODE: usize = 3;
/// Octet mask for the AA flag being set (authoritative)
pub const HEADER_MASK_AA: u8 = 0b0000_0100;
/// Octet mask for the TC flag being set (truncated)
pub const HEADER_MASK_TC: u8 = 0b0000_0010;
/// Octet mask for the RD flag being set (desired)
pub const HEADER_MASK_RD: u8 = 0b0000_0001;
/// Octet mask for the RA flag being set (available)
pub const HEADER_MASK_RA: u8 = 0b1000_0000;
/// Octet mask for the rcode field.
pub const HEADER_MASK_RCODE: u8 = 0b0000_1111;
/// Offset for the rcode field.
pub const HEADER_OFFSET_RCODE: usize = 0;
/// Basic DNS message format, used for both queries and responses.
///
/// ```text
/// +---------------------+
/// | Header |
/// +---------------------+
/// | Question | the question for the name server
/// +---------------------+
/// | Answer | RRs answering the question
/// +---------------------+
/// | Authority | RRs pointing toward an authority
/// +---------------------+
/// | Additional | RRs holding additional information
/// +---------------------+
/// ```
///
/// See section 4.1 of RFC 1035.
#[derive(Debug, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
#[cfg_attr(any(feature = "test-util", test), derive(arbitrary::Arbitrary))]
pub struct Message {
pub header: Header,
pub questions: Vec<Question>,
pub answers: Vec<ResourceRecord>,
pub authority: Vec<ResourceRecord>,
pub additional: Vec<ResourceRecord>,
}
impl Message {
pub fn make_response(&self) -> Self {
Self {
header: Header {
id: self.header.id,
is_response: true,
opcode: self.header.opcode,
is_authoritative: false,
is_truncated: false,
recursion_desired: self.header.recursion_desired,
recursion_available: true,
rcode: Rcode::NoError,
},
questions: self.questions.clone(),
answers: Vec::new(),
authority: Vec::new(),
additional: Vec::new(),
}
}
pub fn make_format_error_response(id: u16) -> Self {
Self {
header: Header {
id,
is_response: true,
opcode: Opcode::Standard,
is_authoritative: false,
is_truncated: false,
recursion_desired: false,
recursion_available: true,
rcode: Rcode::FormatError,
},
questions: Vec::new(),
answers: Vec::new(),
authority: Vec::new(),
additional: Vec::new(),
}
}
pub fn from_question(id: u16, question: Question) -> Self {
Self {
header: Header {
id,
is_response: false,
opcode: Opcode::Standard,
is_authoritative: false,
is_truncated: false,
recursion_desired: false,
recursion_available: false,
rcode: Rcode::NoError,
},
questions: vec![question],
answers: Vec::new(),
authority: Vec::new(),
additional: Vec::new(),
}
}
}
/// Common header type for all messages.
///
/// ```text
/// 1 1 1 1 1 1
/// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// | ID |
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// |QR| Opcode |AA|TC|RD|RA| Z | RCODE |
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// | QDCOUNT |
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// | ANCOUNT |
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// | NSCOUNT |
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// | ARCOUNT |
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// ```
///
/// See section 4.1.1 of RFC 1035.
///
/// The QECOUNT, ANCOUNT, NSCOUNT, and ARCOUNT fields are omitted from this
/// type, as they are only used during serialisation and deserialisation and can
/// be inferred from the other `Message` fields.
#[derive(Debug, Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
#[cfg_attr(any(feature = "test-util", test), derive(arbitrary::Arbitrary))]
pub struct Header {
/// A 16 bit identifier assigned by the program that generates any
/// kind of query. This identifier is copied the corresponding
/// reply and can be used by the requester to match up replies to
/// outstanding queries.
pub id: u16,
/// A one bit field that specifies whether this message is a query
/// (0), or a response (1).
pub is_response: bool,
/// A four bit field that specifies kind of query in this message.
/// This value is set by the originator of a query and copied into
/// the response. The values are:
///
/// - `0` a standard query (`QUERY`)
///
/// - `1` an inverse query (`IQUERY`)
///
/// - `2` a server status request (`STATUS`)
///
/// - `3-15` reserved for future use
pub opcode: Opcode,
/// Authoritative Answer - this bit is valid in responses, and
/// specifies that the responding name server is an authority for
/// the domain name in question section.
///
/// Note that the contents of the answer section may have multiple
/// owner names because of aliases. The AA bit corresponds to the
/// name which matches the query name, or the first owner name in
/// the answer section.
pub is_authoritative: bool,
/// Truncation - specifies that this message was truncated due to
/// length greater than that permitted on the transmission
/// channel.
pub is_truncated: bool,
/// Recursion Desired - this bit may be set in a query and is
/// copied into the response. If RD is set, it directs the name
/// server to pursue the query recursively. Recursive query
/// support is optional.
pub recursion_desired: bool,
/// Recursion Available - this be is set or cleared in a response,
/// and denotes whether recursive query support is available in
/// the name server.
pub recursion_available: bool,
/// Response code - this 4 bit field is set as part of responses.
/// The values have the following interpretation:
///
/// - `0` No error condition
///
/// - `1` Format error - The name server was unable to interpret
/// the query.
///
/// - `2` Server failure - The name server was unable to process
/// this query due to a problem with the name server.
///
/// - `3` Name Error - Meaningful only for responses from an
/// authoritative name server, this code signifies that the
/// domain name referenced in the query does not exist.
///
/// - `4` Not Implemented - The name server does not support the
/// requested kind of query.
///
/// - `5` Refused - The name server refuses to perform the
/// specified operation for policy reasons. For example, a
/// name server may not wish to provide the information to
/// the particular requester, or a name server may not wish
/// to perform a particular operation (e.g., zone transfer)
/// for particular data.
///
/// - `6-15` Reserved for future use.
pub rcode: Rcode,
}
/// The question section has a list of questions (usually 1 but
/// possibly more) being asked. This is the structure for a single
/// question.
///
/// ```text
/// 1 1 1 1 1 1
/// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// | |
/// / QNAME /
/// / /
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// | QTYPE |
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// | QCLASS |
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// ```
///
/// See section 4.1.2 of RFC 1035.
#[derive(Debug, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
#[cfg_attr(any(feature = "test-util", test), derive(arbitrary::Arbitrary))]
pub struct Question {
/// a domain name represented as a sequence of labels, where each
/// label consists of a length octet followed by that number of
/// octets. The domain name terminates with the zero length octet
/// for the null label of the root. Note that this field may be
/// an odd number of octets; no padding is used.
pub name: DomainName,
/// a two octet code which specifies the type of the query. The
/// values for this field include all codes valid for a TYPE
/// field, together with some more general codes which can match
/// more than one type of RR.
pub qtype: QueryType,
/// a two octet code that specifies the class of the query. For
/// example, the QCLASS field is IN for the Internet.
pub qclass: QueryClass,
}
impl Question {
pub fn is_unknown(&self) -> bool {
self.qtype.is_unknown() || self.qclass.is_unknown()
}
}
impl fmt::Display for Question {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
write!(
f,
"{} {} {}",
self.name.to_dotted_string(),
self.qclass,
self.qtype
)
}
}
/// The answer, authority, and additional sections are all the same
/// format: a variable number of resource records. This is the
/// structure for a single resource record.
///
/// ```text
/// 1 1 1 1 1 1
/// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// | |
/// / /
/// / NAME /
/// | |
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// | TYPE |
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// | CLASS |
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// | TTL |
/// | |
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// | RDLENGTH |
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--|
/// / RDATA /
/// / /
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// ```
///
/// See section 4.1.3 of RFC 1035.
#[derive(Debug, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
#[cfg_attr(any(feature = "test-util", test), derive(arbitrary::Arbitrary))]
pub struct ResourceRecord {
/// a domain name to which this resource record pertains.
pub name: DomainName,
/// A combination of the RTYPE and RDATA fields
pub rtype_with_data: RecordTypeWithData,
/// two octets which specify the class of the data in the RDATA
/// field.
pub rclass: RecordClass,
/// a 32 bit unsigned integer that specifies the time interval (in
/// seconds) that the resource record may be cached before it
/// should be discarded. Zero values are interpreted to mean that
/// the RR can only be used for the transaction in progress, and
/// should not be cached.
pub ttl: u32,
}
impl ResourceRecord {
pub fn is_unknown(&self) -> bool {
self.rtype_with_data.is_unknown() || self.rclass.is_unknown()
}
pub fn matches(&self, question: &Question) -> bool {
self.rtype_with_data.matches(question.qtype) && self.rclass.matches(question.qclass)
}
}
/// A record type with its associated, deserialised, data.
#[derive(Debug, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
pub enum RecordTypeWithData {
/// ```text
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// | ADDRESS |
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// ```
///
/// Where `ADDRESS` is a 32 bit Internet address.
A { address: Ipv4Addr },
/// ```text
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// / NSDNAME /
/// / /
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// ```
///
/// Where `NSDNAME` is a domain name which specifies a host which
/// should be authoritative for the specified class and domain.
NS { nsdname: DomainName },
/// ```text
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// / MADNAME /
/// / /
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// ```
///
/// Where `MADNAME` is a domain name which specifies a host which
/// has a mail agent for the domain which should be able to
/// deliver mail for the domain.
MD { madname: DomainName },
/// ```text
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// / MADNAME /
/// / /
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// ```
///
/// Where `MADNAME` is a domain name which specifies a host which
/// has a mail agent for the domain which will accept mail for
/// forwarding to the domain.
MF { madname: DomainName },
/// ```text
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// / CNAME /
/// / /
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// ```
///
/// Where `CNAME` is a domain name which specifies the canonical
/// or primary name for the owner. The owner name is an alias.
CNAME { cname: DomainName },
/// ```text
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// / MNAME /
/// / /
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// / RNAME /
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// | SERIAL |
/// | |
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// | REFRESH |
/// | |
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// | RETRY |
/// | |
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// | EXPIRE |
/// | |
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// | MINIMUM |
/// | |
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// ```
///
/// Where `MNAME` is the domain name of the name server that was
/// the original or primary source of data for this zone.
///
/// Where `RNAME` is a domain name which specifies the mailbox of
/// the person responsible for this zone.
///
/// Where `SERIAL` is the unsigned 32 bit version number of the
/// original copy of the zone. Zone transfers preserve this
/// value. This value wraps and should be compared using sequence
/// space arithmetic.
///
/// Where `REFRESH` is a 32 bit time interval before the zone
/// should be refreshed.
///
/// Where `RETRY` is a 32 bit time interval that should elapse
/// before a failed refresh should be retried.
///
/// Where `EXPIRE` is a 32 bit time value that specifies an upper
/// limit on the time interval that can elapse before the zone is
/// no longer authoritative.
///
/// Where `MINIMUM` is the unsigned 32 bit minimum TTL field that
/// should be exported with any RR from this zone.
///
/// All times are in units of seconds.
SOA {
mname: DomainName,
rname: DomainName,
serial: u32,
refresh: u32,
retry: u32,
expire: u32,
minimum: u32,
},
/// ```text
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// / MADNAME /
/// / /
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// ```
///
/// Where `MADNAME` is a domain name which specifies a host which
/// has the specified mailbox.
MB { madname: DomainName },
/// ```text
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// / MGMNAME /
/// / /
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// ```
///
/// Where `MGMNAME` is a domain name which specifies a mailbox
/// which is a member of the mail group specified by the domain
/// name.
MG { mdmname: DomainName },
/// ```text
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// / NEWNAME /
/// / /
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// ```
///
/// Where `NEWNAME` is a domain name which specifies a mailbox
/// which is the proper rename of the specifies mailbox.
MR { newname: DomainName },
/// ```text
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// / <anything> /
/// / /
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// ```
///
/// Anything at all may be in the RDATA field so long as it is
/// 65535 octets or less.
NULL { octets: Bytes },
/// This application does not interpret `WKS` records.
WKS { octets: Bytes },
/// ```text
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// / PTRDNAME /
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// ```
///
/// Where `PTRDNAME` is a domain name which points to some
/// location in the domain name space.
PTR { ptrdname: DomainName },
/// This application does not interpret `HINFO` records.
HINFO { octets: Bytes },
/// ```text
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// / RMAILBX /
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// / EMAILBX /
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// ```
///
/// Where `RMAILBX` is a domain name which specifies a mailbox
/// which is responsible for the mailing list or mailbox. If this
/// domain name names the root, the owner of the `MINFO` RR is
/// responsible for itself.
///
/// Where `EMAILBX` is a domain name which specifies a mailbox
/// which is to receive error messages related to the mailing list
/// or mailbox specified by the owner of the `MINFO` RR (similar
/// to the `ERRORS-TO`: field which has been proposed). If this
/// domain name names the root, errors should be returned to the
/// sender of the message.
MINFO {
rmailbx: DomainName,
emailbx: DomainName,
},
/// ```text
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// | PREFERENCE |
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// / EXCHANGE /
/// / /
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// ```
///
/// Where `PREFERENCE` is a 16 bit integer which specifies the
/// preference given to this RR among others at the same owner.
/// Lower values are preferred.
///
/// Where `EXCHANGE` is a domain name which specifies a host
/// willing to act as a mail exchange for the owner name.
MX {
preference: u16,
exchange: DomainName,
},
/// ```text
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// / TXT-DATA /
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// ```
///
/// Where `TXT-DATA` is one or more character strings.
TXT { octets: Bytes },
/// ```text
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// | ADDRESS |
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// ```
///
/// Where `ADDRESS` is a 128 bit Internet address.
AAAA { address: Ipv6Addr },
/// ```text
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// | PRIORITY |
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// | WEIGHT |
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// | PORT |
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// / TARGET /
/// / /
/// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/// ```
///
/// Where `PRIORITY` is a 16 bit integer which specifies the order
/// (lowest first) in which clients must attempt to use these RRs.
///
/// Where `WEIGHT` is a 16 bit integer which specifies the
/// preference given to this RR amongst others of the same
/// priority.
///
/// Where `PORT` is a 16 bit integer defining the port to contact
/// the service on.
///
/// Where `TARGET` is the domain name the service may be found at.
/// This should point to a domain name that has an address record
/// (A or AAAA) directly, rather than a domain name which has a
/// CNAME or other alias type. But this is not enforced.
SRV {
priority: u16,
weight: u16,
port: u16,
target: DomainName,
},
/// Any other record.
Unknown {
tag: RecordTypeUnknown,
octets: Bytes,
},
}
impl RecordTypeWithData {
pub fn is_unknown(&self) -> bool {
self.rtype().is_unknown()
}
pub fn matches(&self, qtype: QueryType) -> bool {
self.rtype().matches(qtype)
}
pub fn rtype(&self) -> RecordType {
match self {
RecordTypeWithData::A { .. } => RecordType::A,
RecordTypeWithData::NS { .. } => RecordType::NS,
RecordTypeWithData::MD { .. } => RecordType::MD,
RecordTypeWithData::MF { .. } => RecordType::MF,
RecordTypeWithData::CNAME { .. } => RecordType::CNAME,
RecordTypeWithData::SOA { .. } => RecordType::SOA,
RecordTypeWithData::MB { .. } => RecordType::MB,
RecordTypeWithData::MG { .. } => RecordType::MG,
RecordTypeWithData::MR { .. } => RecordType::MR,
RecordTypeWithData::NULL { .. } => RecordType::NULL,
RecordTypeWithData::WKS { .. } => RecordType::WKS,
RecordTypeWithData::PTR { .. } => RecordType::PTR,
RecordTypeWithData::HINFO { .. } => RecordType::HINFO,
RecordTypeWithData::MINFO { .. } => RecordType::MINFO,
RecordTypeWithData::MX { .. } => RecordType::MX,
RecordTypeWithData::TXT { .. } => RecordType::TXT,
RecordTypeWithData::AAAA { .. } => RecordType::AAAA,
RecordTypeWithData::SRV { .. } => RecordType::SRV,
RecordTypeWithData::Unknown { tag, .. } => RecordType::Unknown(*tag),
}
}
}
#[cfg(any(feature = "test-util", test))]
impl<'a> arbitrary::Arbitrary<'a> for RecordTypeWithData {
// this is pretty verbose but it feels like a better way to guarantee the
// max size of the `Bytes`s than adding a wrapper type
fn arbitrary(u: &mut arbitrary::Unstructured<'a>) -> arbitrary::Result<Self> {
let len = u.int_in_range(0..=128)?;
let octets = Bytes::copy_from_slice(u.bytes(len)?);
let rtype_with_data = match u.arbitrary::<RecordType>()? {
RecordType::A => RecordTypeWithData::A {
address: u.arbitrary()?,
},
RecordType::NS => RecordTypeWithData::NS {
nsdname: u.arbitrary()?,
},
RecordType::MD => RecordTypeWithData::MD {
madname: u.arbitrary()?,
},
RecordType::MF => RecordTypeWithData::MF {
madname: u.arbitrary()?,
},
RecordType::CNAME => RecordTypeWithData::CNAME {
cname: u.arbitrary()?,
},
RecordType::SOA => RecordTypeWithData::SOA {
mname: u.arbitrary()?,
rname: u.arbitrary()?,
serial: u.arbitrary()?,
refresh: u.arbitrary()?,
retry: u.arbitrary()?,
expire: u.arbitrary()?,
minimum: u.arbitrary()?,
},
RecordType::MB => RecordTypeWithData::MB {
madname: u.arbitrary()?,
},
RecordType::MG => RecordTypeWithData::MG {
mdmname: u.arbitrary()?,
},
RecordType::MR => RecordTypeWithData::MR {
newname: u.arbitrary()?,
},
RecordType::NULL => RecordTypeWithData::NULL { octets },
RecordType::WKS => RecordTypeWithData::WKS { octets },
RecordType::PTR => RecordTypeWithData::PTR {
ptrdname: u.arbitrary()?,
},
RecordType::HINFO => RecordTypeWithData::HINFO { octets },
RecordType::MINFO => RecordTypeWithData::MINFO {
rmailbx: u.arbitrary()?,
emailbx: u.arbitrary()?,
},
RecordType::MX => RecordTypeWithData::MX {
preference: u.arbitrary()?,
exchange: u.arbitrary()?,
},
RecordType::TXT => RecordTypeWithData::TXT { octets },
RecordType::AAAA => RecordTypeWithData::AAAA {
address: u.arbitrary()?,
},
RecordType::SRV => RecordTypeWithData::SRV {
priority: u.arbitrary()?,
weight: u.arbitrary()?,
port: u.arbitrary()?,
target: u.arbitrary()?,
},
RecordType::Unknown(tag) => RecordTypeWithData::Unknown { tag, octets },
};
Ok(rtype_with_data)
}
}
/// What sort of query this is.
#[derive(Debug, Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
pub enum Opcode {
Standard,
Inverse,
Status,
Reserved(OpcodeReserved),
}
/// A struct with a private constructor, to ensure invalid `Opcode`s
/// cannot be created.
#[derive(Debug, Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
pub struct OpcodeReserved(u8);
impl Opcode {
pub fn is_reserved(&self) -> bool {
matches!(self, Opcode::Reserved(_))
}
}
impl From<u8> for Opcode {
fn from(octet: u8) -> Self {
match octet & 0b0000_1111 {
0 => Opcode::Standard,
1 => Opcode::Inverse,
2 => Opcode::Status,
other => Opcode::Reserved(OpcodeReserved(other)),
}
}
}
impl From<Opcode> for u8 {
fn from(value: Opcode) -> Self {
match value {
Opcode::Standard => 0,
Opcode::Inverse => 1,
Opcode::Status => 2,
Opcode::Reserved(OpcodeReserved(octet)) => octet,
}
}
}
#[cfg(any(feature = "test-util", test))]
impl<'a> arbitrary::Arbitrary<'a> for Opcode {
fn arbitrary(u: &mut arbitrary::Unstructured<'a>) -> arbitrary::Result<Self> {
Ok(Self::from(u.arbitrary::<u8>()?))
}
}
/// What sort of response this is.
#[derive(Debug, Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
pub enum Rcode {
NoError,
FormatError,
ServerFailure,
NameError,
NotImplemented,
Refused,
Reserved(RcodeReserved),
}
/// A struct with a private constructor, to ensure invalid `Rcode`s
/// cannot be created.
#[derive(Debug, Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
pub struct RcodeReserved(u8);
impl Rcode {
pub fn is_reserved(&self) -> bool {
matches!(self, Rcode::Reserved(_))
}
}
impl fmt::Display for Rcode {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
match self {
Rcode::NoError => write!(f, "no-error"),
Rcode::FormatError => write!(f, "format-error"),
Rcode::ServerFailure => write!(f, "server-failure"),
Rcode::NameError => write!(f, "name-error"),
Rcode::NotImplemented => write!(f, "not-implemented"),
Rcode::Refused => write!(f, "refused"),
Rcode::Reserved(_) => write!(f, "reserved"),
}
}
}
impl From<u8> for Rcode {
fn from(octet: u8) -> Self {
match octet & 0b0000_1111 {
0 => Rcode::NoError,
1 => Rcode::FormatError,
2 => Rcode::ServerFailure,
3 => Rcode::NameError,
4 => Rcode::NotImplemented,
5 => Rcode::Refused,
other => Rcode::Reserved(RcodeReserved(other)),
}
}
}
impl From<Rcode> for u8 {
fn from(value: Rcode) -> Self {
match value {
Rcode::NoError => 0,
Rcode::FormatError => 1,
Rcode::ServerFailure => 2,
Rcode::NameError => 3,
Rcode::NotImplemented => 4,
Rcode::Refused => 5,
Rcode::Reserved(RcodeReserved(octet)) => octet,
}
}
}
#[cfg(any(feature = "test-util", test))]
impl<'a> arbitrary::Arbitrary<'a> for Rcode {
fn arbitrary(u: &mut arbitrary::Unstructured<'a>) -> arbitrary::Result<Self> {
Ok(Self::from(u.arbitrary::<u8>()?))
}
}
/// A domain name is a sequence of labels, where each label is a
/// length octet followed by that number of octets.
///
/// A label must be 63 octets or shorter. A name must be 255 octets
/// or shorter in total, including both length and label octets.
#[derive(Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
pub struct DomainName {
pub labels: Vec<Label>,
// INVARIANT: len == len(labels) + sum(map(len, labels))
pub len: usize,
}
impl DomainName {
pub fn root_domain() -> Self {
DomainName {
labels: vec![Label::new()],
len: 1,
}
}
pub fn is_root(&self) -> bool {
self.len == 1 && self.labels[0].is_empty()
}
pub fn is_subdomain_of(&self, other: &DomainName) -> bool {
self.labels.ends_with(&other.labels)
}
pub fn make_subdomain_of(&self, origin: &Self) -> Option<Self> {
let mut labels = self.labels.clone();
labels.pop();
labels.append(&mut origin.labels.clone());
DomainName::from_labels(labels)
}
pub fn to_dotted_string(&self) -> String {
if self.is_root() {
return ".".to_string();
}
let mut out = String::with_capacity(self.len);
let mut first = true;
for label in &self.labels {
if first {
first = false;
} else {
out.push('.');
}
for octet in &label.octets {
out.push(*octet as char);
}
}
out
}
pub fn from_relative_dotted_string(origin: &Self, s: &str) -> Option<Self> {
if s.is_empty() {
Some(origin.clone())
} else if s.to_string().ends_with('.') {
Self::from_dotted_string(s)
} else {
let suffix = origin.to_dotted_string();
if suffix.starts_with('.') {
Self::from_dotted_string(&format!("{s}{suffix}"))
} else {
Self::from_dotted_string(&format!("{s}.{suffix}"))
}
}
}
pub fn from_dotted_string(s: &str) -> Option<Self> {
if s == "." {
return Some(Self::root_domain());
}
let chunks = s.split('.').collect::<Vec<_>>();
let mut labels = Vec::with_capacity(chunks.len());
for (i, label_chars) in chunks.iter().enumerate() {
if label_chars.is_empty() && i != chunks.len() - 1 {
return None;
}
match label_chars.as_bytes().try_into() {
Ok(label) => labels.push(label),
Err(_) => return None,
}
}
Self::from_labels(labels)
}
pub fn from_labels(labels: Vec<Label>) -> Option<Self> {
if labels.is_empty() {
return None;
}
let mut len = labels.len();
let mut blank_label = false;
for label in &labels {
if blank_label {
return None;
}
blank_label |= label.is_empty();
len += label.len() as usize;
}
if blank_label && len <= DOMAINNAME_MAX_LEN {
Some(Self { labels, len })
} else {
None
}
}
}
impl fmt::Debug for DomainName {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
f.debug_struct("DomainName")
.field("to_dotted_string()", &self.to_dotted_string())
.finish()
}
}
impl fmt::Display for DomainName {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
write!(f, "{}", &self.to_dotted_string())
}
}
impl FromStr for DomainName {
type Err = DomainNameFromStr;
fn from_str(s: &str) -> Result<Self, Self::Err> {
if let Some(domain) = DomainName::from_dotted_string(s) {
Ok(domain)
} else {
Err(DomainNameFromStr::NoParse)
}
}
}
/// Errors that can arise when converting a `&str` into a `DomainName`.
#[derive(Debug, Copy, Clone, Eq, PartialEq, Hash)]
pub enum DomainNameFromStr {
NoParse,
}
impl fmt::Display for DomainNameFromStr {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
write!(f, "could not parse string to domain name")
}
}
impl std::error::Error for DomainNameFromStr {
fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
None
}
}
#[cfg(any(feature = "test-util", test))]
impl<'a> arbitrary::Arbitrary<'a> for DomainName {
fn arbitrary(u: &mut arbitrary::Unstructured<'a>) -> arbitrary::Result<Self> {
let num_labels = u.int_in_range::<usize>(0..=10)?;
let mut labels = Vec::new();
for _ in 0..num_labels {
labels.push(u.arbitrary()?);
}
labels.push(Label::new());
Ok(DomainName::from_labels(labels).unwrap())
}
}
/// A label is just a sequence of octets, which are compared as
/// case-insensitive ASCII. A label can be no longer than 63 octets.
#[derive(Debug, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
pub struct Label {
/// Private to this module so constructing an invalid `Label` is
/// impossible.
octets: Bytes,
}
impl Label {
/// Create a new, empty, label.
pub fn new() -> Self {
Self {
octets: Bytes::new(),
}
}
#[allow(clippy::missing_panics_doc)]
pub fn len(&self) -> u8 {
// safe as the `TryFrom` ensures a label is <= 63 bytes
self.octets.len().try_into().unwrap()
}
pub fn is_empty(&self) -> bool {
self.octets.is_empty()
}
pub fn octets(&self) -> &Bytes {
&self.octets
}
}
impl Default for Label {
fn default() -> Self {
Self::new()
}
}
impl TryFrom<&[u8]> for Label {
type Error = LabelTryFromOctetsError;
fn try_from(mixed_case_octets: &[u8]) -> Result<Self, Self::Error> {
if mixed_case_octets.len() > LABEL_MAX_LEN {
return Err(LabelTryFromOctetsError::TooLong);
}
Ok(Self {
octets: Bytes::copy_from_slice(&mixed_case_octets.to_ascii_lowercase()),
})
}
}
#[cfg(any(feature = "test-util", test))]
impl<'a> arbitrary::Arbitrary<'a> for Label {
// only generates non-empty labels
fn arbitrary(u: &mut arbitrary::Unstructured<'a>) -> arbitrary::Result<Label> {
let label_len = u.int_in_range::<u8>(1..=20)?;
let mut octets = BytesMut::with_capacity(label_len.into());
let bs = u.bytes(label_len.into())?;
for b in bs {
let ascii_byte = if b.is_ascii() { *b } else { *b % 128 };
octets.put_u8(
if ascii_byte == b'.'
|| ascii_byte == b'*'
|| ascii_byte == b'@'
|| ascii_byte == b'#'
|| (ascii_byte as char).is_whitespace()
{
b'x'
} else {
ascii_byte.to_ascii_lowercase()
},
);
}
Ok(Self {
octets: octets.freeze(),
})
}
}
/// Errors that can arise when converting a `[u8]` into a `Label`.
#[derive(Debug, Copy, Clone, Eq, PartialEq, Hash)]
pub enum LabelTryFromOctetsError {
TooLong,
}
/// Query types are a superset of record types.
#[derive(Debug, Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
pub enum QueryType {
Record(RecordType),
AXFR,
MAILB,
MAILA,
Wildcard,
}
impl QueryType {
pub fn is_unknown(&self) -> bool {
match self {
QueryType::Record(rtype) => rtype.is_unknown(),
_ => false,
}
}
}
impl fmt::Display for QueryType {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
match self {
QueryType::Record(rtype) => rtype.fmt(f),
QueryType::AXFR => write!(f, "AXFR"),
QueryType::MAILA => write!(f, "MAILA"),
QueryType::MAILB => write!(f, "MAILB"),
QueryType::Wildcard => write!(f, "ANY"),
}
}
}
impl FromStr for QueryType {
type Err = RecordTypeFromStr;
fn from_str(s: &str) -> Result<Self, Self::Err> {
match s {
"AXFR" => Ok(QueryType::AXFR),
"MAILA" => Ok(QueryType::MAILA),
"MAILB" => Ok(QueryType::MAILB),
"ANY" => Ok(QueryType::Wildcard),
_ => RecordType::from_str(s).map(QueryType::Record),
}
}
}
impl From<u16> for QueryType {
fn from(value: u16) -> Self {
match value {
252 => QueryType::AXFR,
253 => QueryType::MAILB,
254 => QueryType::MAILA,
255 => QueryType::Wildcard,
_ => QueryType::Record(RecordType::from(value)),
}
}
}
impl From<QueryType> for u16 {
fn from(value: QueryType) -> Self {
match value {
QueryType::AXFR => 252,
QueryType::MAILB => 253,
QueryType::MAILA => 254,
QueryType::Wildcard => 255,
QueryType::Record(rtype) => rtype.into(),
}
}
}
#[cfg(any(feature = "test-util", test))]
impl<'a> arbitrary::Arbitrary<'a> for QueryType {
fn arbitrary(u: &mut arbitrary::Unstructured<'a>) -> arbitrary::Result<Self> {
Ok(Self::from(u.arbitrary::<u16>()?))
}
}
/// Query classes are a superset of record classes.
#[derive(Debug, Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
pub enum QueryClass {
Record(RecordClass),
Wildcard,
}
impl QueryClass {
pub fn is_unknown(&self) -> bool {
match self {
QueryClass::Record(rclass) => rclass.is_unknown(),
QueryClass::Wildcard => false,
}
}
}
impl fmt::Display for QueryClass {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
match self {
QueryClass::Record(rclass) => rclass.fmt(f),
QueryClass::Wildcard => write!(f, "ANY"),
}
}
}
impl FromStr for QueryClass {
type Err = RecordClassFromStr;
fn from_str(s: &str) -> Result<Self, Self::Err> {
match s {
"ANY" => Ok(QueryClass::Wildcard),
_ => RecordClass::from_str(s).map(QueryClass::Record),
}
}
}
impl From<u16> for QueryClass {
fn from(value: u16) -> Self {
match value {
255 => QueryClass::Wildcard,
_ => QueryClass::Record(RecordClass::from(value)),
}
}
}
impl From<QueryClass> for u16 {
fn from(value: QueryClass) -> Self {
match value {
QueryClass::Wildcard => 255,
QueryClass::Record(rclass) => rclass.into(),
}
}
}
#[cfg(any(feature = "test-util", test))]
impl<'a> arbitrary::Arbitrary<'a> for QueryClass {
fn arbitrary(u: &mut arbitrary::Unstructured<'a>) -> arbitrary::Result<Self> {
Ok(Self::from(u.arbitrary::<u16>()?))
}
}
/// Record types are used by resource records and by queries.
#[derive(Debug, Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
pub enum RecordType {
A,
NS,
MD,
MF,
CNAME,
SOA,
MB,
MG,
MR,
NULL,
WKS,
PTR,
HINFO,
MINFO,
MX,
TXT,
AAAA,
SRV,
Unknown(RecordTypeUnknown),
}
/// A struct with a private constructor, to ensure invalid `RecordType`s
/// cannot be created.
#[derive(Debug, Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
pub struct RecordTypeUnknown(u16);
impl RecordType {
pub fn is_unknown(&self) -> bool {
matches!(self, RecordType::Unknown(_))
}
pub fn matches(&self, qtype: QueryType) -> bool {
match qtype {
QueryType::Wildcard => true,
QueryType::Record(rtype) => rtype == *self,
_ => false,
}
}
}
impl fmt::Display for RecordType {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
match self {
RecordType::A => write!(f, "A"),
RecordType::NS => write!(f, "NS"),
RecordType::MD => write!(f, "MD"),
RecordType::MF => write!(f, "MF"),
RecordType::CNAME => write!(f, "CNAME"),
RecordType::SOA => write!(f, "SOA"),
RecordType::MB => write!(f, "MB"),
RecordType::MG => write!(f, "MG"),
RecordType::MR => write!(f, "MR"),
RecordType::NULL => write!(f, "NULL"),
RecordType::WKS => write!(f, "WKS"),
RecordType::PTR => write!(f, "PTR"),
RecordType::HINFO => write!(f, "HINFO"),
RecordType::MINFO => write!(f, "MINFO"),
RecordType::MX => write!(f, "MX"),
RecordType::TXT => write!(f, "TXT"),
RecordType::AAAA => write!(f, "AAAA"),
RecordType::SRV => write!(f, "SRV"),
RecordType::Unknown(RecordTypeUnknown(n)) => write!(f, "TYPE{n}"),
}
}
}
impl FromStr for RecordType {
type Err = RecordTypeFromStr;
fn from_str(s: &str) -> Result<Self, Self::Err> {
match s {
"A" => Ok(RecordType::A),
"NS" => Ok(RecordType::NS),
"MD" => Ok(RecordType::MD),
"MF" => Ok(RecordType::MF),
"CNAME" => Ok(RecordType::CNAME),
"SOA" => Ok(RecordType::SOA),
"MB" => Ok(RecordType::MB),
"MG" => Ok(RecordType::MG),
"MR" => Ok(RecordType::MR),
"NULL" => Ok(RecordType::NULL),
"WKS" => Ok(RecordType::WKS),
"PTR" => Ok(RecordType::PTR),
"HINFO" => Ok(RecordType::HINFO),
"MINFO" => Ok(RecordType::MINFO),
"MX" => Ok(RecordType::MX),
"TXT" => Ok(RecordType::TXT),
"AAAA" => Ok(RecordType::AAAA),
"SRV" => Ok(RecordType::SRV),
_ => {
if let Some(type_str) = s.strip_prefix("TYPE") {
if let Ok(type_num) = u16::from_str(type_str) {
Ok(RecordType::from(type_num))
} else {
Err(RecordTypeFromStr::BadType)
}
} else {
Err(RecordTypeFromStr::NoParse)
}
}
}
}
}
/// Errors that can arise when converting a `&str` into a `RecordType`.
#[derive(Debug, Copy, Clone, Eq, PartialEq, Hash)]
pub enum RecordTypeFromStr {
BadType,
NoParse,
}
impl fmt::Display for RecordTypeFromStr {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
match self {
RecordTypeFromStr::BadType => write!(f, "TYPE<num> number must be a u16"),
RecordTypeFromStr::NoParse => write!(f, "could not parse string to type"),
}
}
}
impl std::error::Error for RecordTypeFromStr {
fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
None
}
}
impl From<u16> for RecordType {
fn from(value: u16) -> Self {
match value {
1 => RecordType::A,
2 => RecordType::NS,
3 => RecordType::MD,
4 => RecordType::MF,
5 => RecordType::CNAME,
6 => RecordType::SOA,
7 => RecordType::MB,
8 => RecordType::MG,
9 => RecordType::MR,
10 => RecordType::NULL,
11 => RecordType::WKS,
12 => RecordType::PTR,
13 => RecordType::HINFO,
14 => RecordType::MINFO,
15 => RecordType::MX,
16 => RecordType::TXT,
28 => RecordType::AAAA,
33 => RecordType::SRV,
_ => RecordType::Unknown(RecordTypeUnknown(value)),
}
}
}
impl From<RecordType> for u16 {
fn from(value: RecordType) -> Self {
match value {
RecordType::A => 1,
RecordType::NS => 2,
RecordType::MD => 3,
RecordType::MF => 4,
RecordType::CNAME => 5,
RecordType::SOA => 6,
RecordType::MB => 7,
RecordType::MG => 8,
RecordType::MR => 9,
RecordType::NULL => 10,
RecordType::WKS => 11,
RecordType::PTR => 12,
RecordType::HINFO => 13,
RecordType::MINFO => 14,
RecordType::MX => 15,
RecordType::TXT => 16,
RecordType::AAAA => 28,
RecordType::SRV => 33,
RecordType::Unknown(RecordTypeUnknown(value)) => value,
}
}
}
#[cfg(any(feature = "test-util", test))]
impl<'a> arbitrary::Arbitrary<'a> for RecordType {
fn arbitrary(u: &mut arbitrary::Unstructured<'a>) -> arbitrary::Result<Self> {
Ok(Self::from(u.arbitrary::<u16>()?))
}
}
/// Record classes are used by resource records and by queries.
#[derive(Debug, Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
pub enum RecordClass {
IN,
Unknown(RecordClassUnknown),
}
/// A struct with a private constructor, to ensure invalid
/// `RecordClass`es cannot be created.
#[derive(Debug, Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
pub struct RecordClassUnknown(u16);
impl RecordClass {
pub fn is_unknown(&self) -> bool {
matches!(self, RecordClass::Unknown(_))
}
pub fn matches(&self, qclass: QueryClass) -> bool {
match qclass {
QueryClass::Wildcard => true,
QueryClass::Record(rclass) => rclass == *self,
}
}
}
impl fmt::Display for RecordClass {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
match self {
RecordClass::IN => write!(f, "IN"),
RecordClass::Unknown(RecordClassUnknown(n)) => write!(f, "CLASS{n}"),
}
}
}
impl FromStr for RecordClass {
type Err = RecordClassFromStr;
fn from_str(s: &str) -> Result<Self, Self::Err> {
match s {
"IN" => Ok(RecordClass::IN),
_ => {
if let Some(class_str) = s.strip_prefix("CLASS") {
if let Ok(class_num) = u16::from_str(class_str) {
Ok(RecordClass::from(class_num))
} else {
Err(RecordClassFromStr::BadClass)
}
} else {
Err(RecordClassFromStr::NoParse)
}
}
}
}
}
/// Errors that can arise when converting a `&str` into a `RecordClass`.
#[derive(Debug, Copy, Clone, Eq, PartialEq, Hash)]
pub enum RecordClassFromStr {
BadClass,
NoParse,
}
impl fmt::Display for RecordClassFromStr {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
match self {
RecordClassFromStr::BadClass => write!(f, "CLASS<num> number must be a u16"),
RecordClassFromStr::NoParse => write!(f, "could not parse string to class"),
}
}
}
impl std::error::Error for RecordClassFromStr {
fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
None
}
}
impl From<u16> for RecordClass {
fn from(value: u16) -> Self {
match value {
1 => RecordClass::IN,
_ => RecordClass::Unknown(RecordClassUnknown(value)),
}
}
}
impl From<RecordClass> for u16 {
fn from(value: RecordClass) -> Self {
match value {
RecordClass::IN => 1,
RecordClass::Unknown(RecordClassUnknown(value)) => value,
}
}
}
#[cfg(any(feature = "test-util", test))]
impl<'a> arbitrary::Arbitrary<'a> for RecordClass {
fn arbitrary(u: &mut arbitrary::Unstructured<'a>) -> arbitrary::Result<Self> {
Ok(Self::from(u.arbitrary::<u16>()?))
}
}
#[cfg(test)]
mod tests {
use rand::Rng;
use super::test_util::*;
use super::*;
#[test]
fn u8_opcode_roundtrip() {
for i in 0..15 {
assert_eq!(u8::from(Opcode::from(i)), i);
}
}
#[test]
fn u8_rcode_roundtrip() {
for i in 0..15 {
assert_eq!(u8::from(Rcode::from(i)), i);
}
}
#[test]
fn u16_querytype_roundtrip() {
for i in 0..100 {
assert_eq!(u16::from(QueryType::from(i)), i);
}
}
#[test]
fn u16_queryclass_roundtrip() {
for i in 0..100 {
assert_eq!(u16::from(QueryClass::from(i)), i);
}
}
#[test]
fn u16_recordtype_roundtrip() {
for i in 0..100 {
assert_eq!(u16::from(RecordType::from(i)), i);
}
}
#[test]
fn recordtype_unknown_implies_querytype_unknown() {
for i in 0..100 {
if RecordType::from(i).is_unknown() {
assert!(QueryType::from(i).is_unknown());
}
}
}
#[test]
fn u16_recordclass_roundtrip() {
for i in 0..100 {
assert_eq!(u16::from(RecordClass::from(i)), i);
}
}
#[test]
fn recordclass_unknown_implies_queryclass_unknown() {
for i in 0..100 {
if RecordClass::from(i).is_unknown() {
assert!(QueryClass::from(i).is_unknown());
}
}
}
#[test]
fn domainname_root_conversions() {
assert_eq!(
Some(DomainName::root_domain()),
DomainName::from_dotted_string(".")
);
assert_eq!(
Some(DomainName::root_domain()),
DomainName::from_labels(vec![Label::new()])
);
assert_eq!(".", DomainName::root_domain().to_dotted_string());
}
#[test]
fn from_relative_dotted_string_empty() {
let origin = domain("com.");
assert_eq!(
Some(domain("com.")),
DomainName::from_relative_dotted_string(&origin, "")
);
}
#[test]
fn from_relative_dotted_string_absolute() {
let origin = domain("com.");
assert_eq!(
Some(domain("www.example.com.")),
DomainName::from_relative_dotted_string(&origin, "www.example.com.")
);
}
#[test]
fn from_relative_dotted_string_relative() {
let origin = domain("com.");
assert_eq!(
Some(domain("www.example.com.")),
DomainName::from_relative_dotted_string(&origin, "www.example")
);
}
#[test]
fn make_subdomain_is_subdomain() {
let sub = domain("foo.");
let apex = domain("bar.");
let combined = sub.make_subdomain_of(&apex);
assert_eq!(Some(domain("foo.bar.")), combined);
assert!(combined.unwrap().is_subdomain_of(&apex));
}
#[test]
fn domainname_conversions() {
let mut rng = rand::thread_rng();
for _ in 0..100 {
let labels_len = rng.gen_range(0..5);
let mut dotted_string_input = String::new();
let mut labels_input = Vec::with_capacity(labels_len);
let mut output = String::new();
for i in 0..labels_len {
let label_len = rng.gen_range(1..10);
if i > 0 {
dotted_string_input.push('.');
output.push('.');
}
let mut octets = BytesMut::with_capacity(label_len);
for _ in 0..label_len {
let mut chr = rng.gen_range(32..126);
if chr == b'.'
|| chr == b'*'
|| chr == b'@'
|| chr == b'#'
|| (chr as char).is_whitespace()
{
chr = b'X';
}
octets.put_u8(chr);
dotted_string_input.push(chr as char);
output.push(chr.to_ascii_lowercase() as char);
}
labels_input.push(Label::try_from(&octets.freeze()[..]).unwrap());
}
labels_input.push(Label::new());
dotted_string_input.push('.');
output.push('.');
assert_eq!(
Some(output.clone()),
DomainName::from_dotted_string(&dotted_string_input).map(|d| d.to_dotted_string())
);
assert_eq!(
Some(output),
DomainName::from_labels(labels_input.clone()).map(|d| d.to_dotted_string())
);
assert_eq!(
DomainName::from_dotted_string(&dotted_string_input).map(|d| d.to_dotted_string()),
DomainName::from_labels(labels_input).map(|d| d.to_dotted_string())
);
}
}
}
#[cfg(any(feature = "test-util", test))]
#[allow(clippy::missing_panics_doc)]
pub mod test_util {
use super::*;
use arbitrary::{Arbitrary, Unstructured};
use rand::Rng;
pub fn arbitrary_resourcerecord() -> ResourceRecord {
let mut rng = rand::thread_rng();
for size in [128, 256, 512, 1024, 2048, 4096] {
let mut buf = BytesMut::with_capacity(size);
for _ in 0..size {
buf.put_u8(rng.gen());
}
if let Ok(rr) = ResourceRecord::arbitrary(&mut Unstructured::new(&buf.freeze())) {
return rr;
}
}
panic!("could not generate arbitrary value!");
}
pub fn domain(name: &str) -> DomainName {
DomainName::from_dotted_string(name).unwrap()
}
pub fn a_record(name: &str, address: Ipv4Addr) -> ResourceRecord {
ResourceRecord {
name: domain(name),
rtype_with_data: RecordTypeWithData::A { address },
rclass: RecordClass::IN,
ttl: 300,
}
}
pub fn aaaa_record(name: &str, address: Ipv6Addr) -> ResourceRecord {
ResourceRecord {
name: domain(name),
rtype_with_data: RecordTypeWithData::AAAA { address },
rclass: RecordClass::IN,
ttl: 300,
}
}
pub fn cname_record(name: &str, target_name: &str) -> ResourceRecord {
ResourceRecord {
name: domain(name),
rtype_with_data: RecordTypeWithData::CNAME {
cname: domain(target_name),
},
rclass: RecordClass::IN,
ttl: 300,
}
}
pub fn ns_record(superdomain_name: &str, nameserver_name: &str) -> ResourceRecord {
ResourceRecord {
name: domain(superdomain_name),
rtype_with_data: RecordTypeWithData::NS {
nsdname: domain(nameserver_name),
},
rclass: RecordClass::IN,
ttl: 300,
}
}
pub fn unknown_record(name: &str, octets: &[u8]) -> ResourceRecord {
ResourceRecord {
name: domain(name),
rtype_with_data: RecordTypeWithData::Unknown {
tag: RecordTypeUnknown(100),
octets: Bytes::copy_from_slice(octets),
},
rclass: RecordClass::IN,
ttl: 300,
}
}
}