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//! A BER-encoded OCTET STRING.
//!
//! This is an internal module. It’s public types are re-exported by the
//! parent.
//!
//! XXX This currently panics when trying to encode an octet string in
//! CER mode. An implementation of that is TODO.
use std::{cmp, hash, io, mem};
use std::convert::Infallible;
use bytes::{BytesMut, Bytes};
use crate::captured::Captured;
use crate::{decode, encode};
use crate::decode::{
BytesSource, DecodeError, IntoSource, Pos, SliceSource, Source
};
use crate::mode::Mode;
use crate::length::Length;
use crate::tag::Tag;
//------------ OctetString ---------------------------------------------------
/// An octet string value.
///
/// An octet string is a sequence of octets, i.e., a glorified `[u8]`. Basic
/// Encoding Rules, however, allow this sequence to be broken up into chunks
/// that are encoded separatedly to allow for very large octet strings and
/// cases where one doesn’t yet know the length of the string.
///
/// In order to avoid unnecessary allocations, this type wraps the raw content
/// octets of a BER encoded octet string. As a consequence, assembling the
/// complete string may actually be costly and should only be done if really
/// necessary. As an alternative, there is an iterator over the parts via the
/// `iter` method or the `IntoIterator` trait as well as an iterator over the
/// individual octets via the `octets` method.
///
/// Octet strings are sometimes used to store BER encoded data. The
/// `OctetStringSource` type, accessible via the `to_source` method, provides
/// an implementation of the `Source` trait to run a decoder on.
///
/// # BER Encoding
///
/// Octet strings are either encoded as a primitive or a constructed value.
/// In the primitive form, the content octets are the string’s octets. In a
/// constructed form, the content is a sequence of encoded octets strings
/// which in turn may be primitive or constructed. In this case, the string’s
/// octets are the concatenation of all the content octets of the primitive
/// forms in the order as encountered.
///
/// In CER, the string must use the primitive form if it is less than 1000
/// octets long and the constructed form otherwise. The constructed form must
/// consists of a sequence of primitive values each exactly with a 1000
/// octets of content except for the last one.
///
/// In DER, only the primitive form is allowed.
#[derive(Clone, Debug)]
pub struct OctetString(Inner<Bytes, Captured>);
/// A type allowing to distinguish between primitive and constructed encoding.
#[derive(Clone, Debug)]
enum Inner<P, C> {
/// The value is encoded in primitive encoding.
Primitive(P),
/// The value is encoded in constructed encoding.
Constructed(C),
}
/// # Content Access
///
impl OctetString {
/// Creates an octet string from a Bytes value.
pub fn new(bytes: Bytes) -> Self {
OctetString(Inner::Primitive(bytes))
}
/// Returns an iterator over the parts of the octet string.
///
/// The iterator will produce `&[u8]` which, when appended produce the
/// complete content of the octet string.
pub fn iter(&self) -> OctetStringIter {
match self.0 {
Inner::Primitive(ref inner) => {
OctetStringIter(Inner::Primitive(inner.as_ref()))
}
Inner::Constructed(ref inner) => {
OctetStringIter(
Inner::Constructed(inner.as_slice().into_source())
)
}
}
}
/// Returns an iterator over the individual octets of the string.
pub fn octets(&self) -> OctetStringOctets {
OctetStringOctets::new(self.iter())
}
/// Returns a reference to the complete content if possible.
///
/// The method will return a bytes slice of the content if the octet
/// string was encoded as a single primitive value or `None` otherwise.
///
/// This is guaranteed to return some slice if the value was produced by
/// decoding in DER mode.
pub fn as_slice(&self) -> Option<&[u8]> {
match self.0 {
Inner::Primitive(ref inner) => Some(inner.as_ref()),
Inner::Constructed(_) => None
}
}
/// Produces a bytes value with the string’s content.
///
/// If the octet string was encoded as a single primitive value, the
/// method will simply clone the content. Otherwise it will produce
/// an entirely new bytes value from the concatenated content of all
/// the primitive values.
pub fn to_bytes(&self) -> Bytes {
if let Inner::Primitive(ref inner) = self.0 {
return inner.clone()
}
let mut res = BytesMut::new();
self.iter().for_each(|x| res.extend_from_slice(x));
res.freeze()
}
/// Converts the octet string into bytes value.
///
/// If the octet string was encoded as a single primitive value, the
/// method will simply return the content. Otherwise it will produce
/// an entirely new bytes value from the concatenated content of all
/// the primitive values.
pub fn into_bytes(self) -> Bytes {
if let Inner::Primitive(inner) = self.0 {
return inner
}
let mut res = BytesMut::new();
self.iter().for_each(|x| res.extend_from_slice(x));
res.freeze()
}
/// Returns the length of the content.
///
/// This is _not_ the length of the encoded value but of the actual
/// octet string.
pub fn len(&self) -> usize {
if let Inner::Primitive(ref inner) = self.0 {
return inner.len()
}
self.iter().fold(0, |len, x| len + x.len())
}
/// Returns whether the content is empty.
pub fn is_empty(&self) -> bool {
if let Inner::Primitive(ref inner) = self.0 {
return inner.is_empty()
}
!self.iter().any(|s| !s.is_empty())
}
}
/// # Parsing and Encoding of Octet Strings
///
impl OctetString {
/// Takes a single octet string value from constructed value content.
///
/// If there is no next value, if the next value does not have the tag
/// `Tag::OCTET_STRING`, or if it doesn’t contain a correctly encoded
/// octet string, a malformed error is returned.
pub fn take_from<S: decode::Source>(
cons: &mut decode::Constructed<S>
) -> Result<Self, DecodeError<S::Error>> {
cons.take_value_if(Tag::OCTET_STRING, Self::from_content)
}
/// Takes an optional octet string value from constructed value content.
///
/// If there is no next value, or if the next value does not have the
/// tag `Tag::OCTET_STRING`, then `Ok(None)` is returned.
///
/// If there is an octet string, but it is not correctly encoded, a
/// malformed error is returned.
pub fn take_opt_from<S: decode::Source>(
cons: &mut decode::Constructed<S>
) -> Result<Option<Self>, DecodeError<S::Error>> {
cons.take_opt_value_if(Tag::OCTET_STRING, Self::from_content)
}
/// Takes an octet string value from content.
pub fn from_content<S: decode::Source>(
content: &mut decode::Content<S>
) -> Result<Self, DecodeError<S::Error>> {
match *content {
decode::Content::Primitive(ref mut inner) => {
if inner.mode() == Mode::Cer && inner.remaining() > 1000 {
return Err(content.content_err(
"long string component in CER mode"
))
}
Ok(OctetString(Inner::Primitive(inner.take_all()?)))
}
decode::Content::Constructed(ref mut inner) => {
match inner.mode() {
Mode::Ber => Self::take_constructed_ber(inner),
Mode::Cer => Self::take_constructed_cer(inner),
Mode::Der => {
Err(content.content_err(
"constructed string in DER mode"
))
}
}
}
}
}
/// Parses a constructed BER encoded octet string.
///
/// It consists octet string values either primitive or constructed.
fn take_constructed_ber<S: decode::Source>(
cons: &mut decode::Constructed<S>
) -> Result<Self, DecodeError<S::Error>> {
cons.capture(|cons| {
while cons.skip_opt(|tag, _, _|
if tag == Tag::OCTET_STRING {
Ok(())
}
else {
Err("expected octet string".into())
}
)?.is_some() { }
Ok(())
}).map(|captured| OctetString(Inner::Constructed(captured)))
}
/// Parses a constructed CER encoded octet string.
///
/// The constructed form contains a sequence of primitive OCTET STRING
/// values each except for the last one exactly 1000 octets long.
fn take_constructed_cer<S: decode::Source>(
constructed: &mut decode::Constructed<S>
) -> Result<Self, DecodeError<S::Error>> {
let mut short = false;
constructed.capture(|con| {
while let Some(()) = con.take_opt_primitive_if(Tag::OCTET_STRING,
|primitive| {
if primitive.remaining() > 1000 {
return Err(primitive.content_err(
"long string component in CER mode"
));
}
if primitive.remaining() < 1000 {
if short {
return Err(primitive.content_err(
"short non-terminal string component in CER mode"
));
}
short = true
}
primitive.skip_all()
})? { }
Ok(())
}).map(|captured| OctetString(Inner::Constructed(captured)))
}
/// Returns a value encoder for the octet string using the natural tag.
pub fn encode(self) -> impl encode::Values {
self.encode_as(Tag::OCTET_STRING)
}
/// Returns a value encoder for the octet string using the given tag.
pub fn encode_as(self, tag: Tag) -> impl encode::Values {
OctetStringEncoder::new(self, tag)
}
/// Returns a value encoder for the octet string using the natural tag.
pub fn encode_ref(&self) -> impl encode::Values + '_ {
self.encode_ref_as(Tag::OCTET_STRING)
}
/// Returns a value encoder for the octet string using the given tag.
pub fn encode_ref_as(&self, tag: Tag) -> impl encode::Values + '_ {
OctetStringEncoder::new(self, tag)
}
/// Returns a value encoder that wraps values into an octet string.
///
/// This function allows an octet string wrapping some values to be
/// created without having to first create the octet string.
pub fn encode_wrapped<V: encode::Values>(
mode: Mode,
values: V
) -> impl encode::Values {
WrappingOctetStringEncoder::new(mode, values)
}
/// Returns a value encoder that encodes a bytes slice as an octet string.
pub fn encode_slice<T>(value: T) -> OctetSliceEncoder<T> {
Self::encode_slice_as(value, Tag::OCTET_STRING)
}
/// Returns a value encoder that encodes a bytes slice as an octet string.
pub fn encode_slice_as<T>(value: T, tag: Tag) -> OctetSliceEncoder<T> {
OctetSliceEncoder::new(value, tag)
}
}
//--- AsRef
//
// We need this for OctetStringEncoder below.
impl AsRef<OctetString> for OctetString {
fn as_ref(&self) -> &Self {
self
}
}
//--- PartialEq and Eq
impl PartialEq for OctetString {
fn eq(&self, other: &OctetString) -> bool {
if let (Some(l), Some(r)) = (self.as_slice(), other.as_slice()) {
return l == r
}
let mut sit = self.iter();
let mut oit = other.iter();
let (mut ssl, mut osl) = match (sit.next(), oit.next()) {
(Some(ssl), Some(osl)) => (ssl, osl),
(None, None) => return true,
_ => return false,
};
loop {
if ssl.is_empty() {
ssl = sit.next().unwrap_or(b"");
}
if osl.is_empty() {
osl = oit.next().unwrap_or(b"");
}
match (ssl.is_empty(), osl.is_empty()) {
(true, true) => return true,
(false, false) => { },
_ => return false,
}
let len = cmp::min(ssl.len(), osl.len());
if ssl[..len] != osl[..len] {
return false
}
ssl = &ssl[len..];
osl = &osl[len..];
}
}
}
impl<T: AsRef<[u8]>> PartialEq<T> for OctetString {
fn eq(&self, other: &T) -> bool {
let mut other = other.as_ref();
if let Some(slice) = self.as_slice() {
return slice == other
}
for part in self.iter() {
if part.len() > other.len() {
return false
}
if part.len() == other.len() {
return part == other
}
if part != &other[..part.len()] {
return false
}
other = &other[part.len()..]
}
false
}
}
impl Eq for OctetString { }
//--- PartialOrd and Ord
impl PartialOrd for OctetString {
fn partial_cmp(&self, other: &Self) -> Option<cmp::Ordering> {
Some(self.cmp(other))
}
}
impl<T: AsRef<[u8]>> PartialOrd<T> for OctetString {
fn partial_cmp(&self, other: &T) -> Option<cmp::Ordering> {
let mut other = other.as_ref();
if let Some(slice ) = self.as_slice() {
return slice.partial_cmp(other)
}
for part in self.iter() {
if part.len() >= other.len() {
return Some(part.cmp(other))
}
match part.cmp(&other[..part.len()]) {
cmp::Ordering::Equal => { }
other => return Some(other)
}
other = &other[part.len()..]
}
Some(cmp::Ordering::Less)
}
}
impl Ord for OctetString {
fn cmp(&self, other: &Self) -> cmp::Ordering {
if let (Some(l), Some(r)) = (self.as_slice(), other.as_slice()) {
return l.cmp(r)
}
let mut siter = self.iter();
let mut oiter = other.iter();
let mut spart = b"".as_ref();
let mut opart = b"".as_ref();
loop {
if spart.is_empty() {
spart = siter.next().unwrap_or(b"");
}
if opart.is_empty() {
opart = oiter.next().unwrap_or(b"");
}
match (spart.is_empty(), opart.is_empty()) {
(true, true) => return cmp::Ordering::Equal,
(true, false) => return cmp::Ordering::Less,
(false, true) => return cmp::Ordering::Greater,
(false, false) => { },
}
let len = cmp::min(spart.len(), opart.len());
match spart[..len].cmp(&opart[..len]) {
cmp::Ordering::Equal => { }
other => return other
}
spart = &spart[len..];
opart = &opart[len..];
}
}
}
//--- Hash
impl hash::Hash for OctetString {
fn hash<H: hash::Hasher>(&self, state: &mut H) {
for part in self.iter() {
part.hash(state)
}
}
}
//--- IntoIterator
impl<'a> IntoIterator for &'a OctetString {
type Item = &'a [u8];
type IntoIter = OctetStringIter<'a>;
fn into_iter(self) -> Self::IntoIter {
self.iter()
}
}
//--- IntoSource
impl IntoSource for OctetString {
type Source = OctetStringSource;
fn into_source(self) -> Self::Source {
OctetStringSource::new(self)
}
}
//------------ OctetStringSource ---------------------------------------------
/// A decode source atop an octet string.
//
// Assuming we have a correctly encoded octet string, its content is a
// sequence of value headers (i.e., tag and length octets) and actual string
// content. There’s three types of headers we could encounter: primitive
// octet strings, constructed octet strings, and end-of-values. The first
// one is followed by as many octets of actual content as given in the
// length octets. The second one is followed by more values recursively and
// the third one is by nothing. So, only the primitive values actually
// contain content and, because however they are nested, they appear in
// order, we can ignore all the rest.
pub struct OctetStringSource {
/// The content of primitive value we currently work on.
current: Bytes,
/// The remainder of the value after the value in `current`.
remainder: BytesSource,
/// The current position in the string.
pos: Pos,
}
impl OctetStringSource {
/// Creates a new source atop an existing octet string.
fn new(from: OctetString) -> Self {
Self::with_offset(from, Pos::default())
}
/// Creates a new source with a given start position.
fn with_offset(from: OctetString, offset: Pos) -> Self {
match from.0 {
Inner::Primitive(inner) => {
OctetStringSource {
current: inner,
remainder: Bytes::new().into_source(),
pos: offset,
}
}
Inner::Constructed(inner) => {
OctetStringSource {
current: Bytes::new(),
remainder: inner.into_bytes().into_source(),
pos: offset,
}
}
}
}
/// Returns the next value for `self.current`.
///
/// This is the content of the first primitive value found in the
/// remainder.
///
/// Returns `None` if we are done.
fn next_current(&mut self) -> Option<Bytes> {
// Unwrapping here is okay. The only error that can happen is that
// the tag is longer that we support. However, we already checked that
// there’s only OctetString or End of Value tags which we _do_
// support.
while let Some((tag, cons)) = Tag::take_opt_from(
&mut self.remainder
).unwrap() {
let length = Length::take_from(
&mut self.remainder, Mode::Ber
).unwrap();
match tag {
Tag::OCTET_STRING => {
if cons {
continue
}
let length = match length {
Length::Definite(len) => len,
_ => unreachable!()
};
return Some(self.remainder.split_to(length))
}
Tag::END_OF_VALUE => continue,
_ => unreachable!()
}
}
None
}
}
impl decode::Source for OctetStringSource {
type Error = Infallible;
fn pos(&self) -> Pos {
self.pos
}
fn request(&mut self, len: usize) -> Result<usize, Self::Error> {
if self.current.len() < len && !self.remainder.is_empty() {
// Make a new current that is at least `len` long.
let mut current = BytesMut::with_capacity(self.current.len());
current.extend_from_slice(&self.current.clone());
while current.len() < len {
if let Some(bytes) = self.next_current() {
current.extend_from_slice(bytes.as_ref())
}
else {
break
}
}
self.current = current.freeze()
}
Ok(self.current.len())
}
fn advance(&mut self, len: usize) {
assert!(len <= self.current.len());
self.pos = self.pos + len.into();
bytes::Buf::advance(&mut self.current, len)
}
fn slice(&self) -> &[u8] {
self.current.as_ref()
}
fn bytes(&self, start: usize, end: usize) -> Bytes {
self.current.slice(start..end)
}
}
//------------ OctetStringIter -----------------------------------------------
/// An iterator over the segments of an octet string.
///
/// You can get a value of this type by calling `OctetString::iter` or relying
/// on the `IntoIterator` impl for a `&OctetString`.
#[derive(Clone, Debug)]
pub struct OctetStringIter<'a>(Inner<&'a [u8], SliceSource<'a>>);
impl<'a> Iterator for OctetStringIter<'a> {
type Item = &'a [u8];
fn next(&mut self) -> Option<Self::Item> {
match self.0 {
Inner::Primitive(ref mut inner) => {
if inner.is_empty() {
None
}
else {
Some(mem::replace(inner, &b""[..]))
}
}
Inner::Constructed(ref mut inner) => {
while !inner.is_empty() {
let (tag, cons) = Tag::take_from(inner).unwrap();
let length = Length::take_from(inner, Mode::Ber).unwrap();
match tag {
Tag::OCTET_STRING => {
if cons {
continue
}
let length = match length {
Length::Definite(len) => len,
_ => unreachable!()
};
return Some(inner.split_to(length))
}
Tag::END_OF_VALUE => continue,
_ => unreachable!()
}
}
None
}
}
}
}
//------------ OctetStringOctets ---------------------------------------------
/// An iterator over the octets in an octet string.
///
/// You can get a value of this type by calling `OctetString::octets`.
#[derive(Clone, Debug)]
pub struct OctetStringOctets<'a> {
cur: &'a [u8],
iter: OctetStringIter<'a>,
}
impl<'a> OctetStringOctets<'a> {
fn new(iter: OctetStringIter<'a>) -> Self {
OctetStringOctets {
cur: b"",
iter
}
}
}
impl<'a> Iterator for OctetStringOctets<'a> {
type Item = u8;
fn next(&mut self) -> Option<u8> {
while self.cur.is_empty() {
let next = match self.iter.next() {
Some(some) => some,
None => return None,
};
self.cur = next;
}
let res = self.cur[0];
self.cur = &self.cur[1..];
Some(res)
}
}
//------------ OctetStringEncoder --------------------------------------------
/// A value encoder for an octet string.
///
/// You can get a value of this type via octet string’s [`encode`] and
/// [`encode_as`] methods.
///
/// [`encode`]: struct.OctetString.html#method.encode
/// [`encode_as`]: struct.OctetString.html#method.encode_as
#[derive(Clone, Debug)]
pub struct OctetStringEncoder<T> {
/// The octet string to encode.
value: T,
/// The tag to used for the encoded value.
tag: Tag,
}
impl<T> OctetStringEncoder<T> {
/// Creates a new octet string encoder.
fn new(value: T, tag: Tag) -> Self {
OctetStringEncoder { value, tag }
}
}
//--- encode::Values
impl<T: AsRef<OctetString>> encode::Values for OctetStringEncoder<T> {
fn encoded_len(&self, mode: Mode) -> usize {
match mode {
Mode::Ber => {
let len = match self.value.as_ref().0 {
Inner::Primitive(ref bytes) => bytes.len(),
Inner::Constructed(ref captured) => captured.len(),
};
self.tag.encoded_len()
+ Length::Definite(len).encoded_len()
+ len
}
Mode::Cer => {
unimplemented!()
}
Mode::Der => {
let len = self.value.as_ref().len();
self.tag.encoded_len()
+ Length::Definite(len).encoded_len()
+ len
}
}
}
fn write_encoded<W: io::Write>(
&self,
mode: Mode,
target: &mut W
) -> Result<(), io::Error> {
match mode {
Mode::Ber => {
match self.value.as_ref().0 {
Inner::Primitive(ref bytes) => {
self.tag.write_encoded(false, target)?;
Length::Definite(bytes.len()).write_encoded(target)?;
target.write_all(bytes.as_ref())
}
Inner::Constructed(ref captured) => {
self.tag.write_encoded(true, target)?;
Length::Definite(captured.len()).write_encoded(target)?;
target.write_all(captured.as_slice())
}
}
}
Mode::Cer => {
unimplemented!()
}
Mode::Der => {
self.tag.write_encoded(false, target)?;
Length::Definite(
self.value.as_ref().len()
).write_encoded(target)?;
for slice in self.value.as_ref().iter() {
target.write_all(slice)?;
}
Ok(())
}
}
}
}
//------------ OctetSliceEncoder ---------------------------------------------
/// A value encoder for a bytes slice as an octet string.
///
/// You can get a value of this type via octet string’s [`encode_slice`] and
/// [`encode_slice_as`] functions.
///
/// [`encode_slice`]: struct.OctetString.html#method.encode_slice
/// [`encode_slice_as`]: struct.OctetString.html#method.encode_slice_as
#[derive(Clone, Debug)]
pub struct OctetSliceEncoder<T> {
/// The slice to encode.
slice: T,
/// The tag to be used for the encoded value.
tag: Tag,
}
impl<T> OctetSliceEncoder<T> {
/// Creates a new octet slice encoder.
fn new(slice: T, tag: Tag) -> Self {
OctetSliceEncoder { slice, tag }
}
}
//--- encode::Values
impl<T: AsRef<[u8]>> encode::Values for OctetSliceEncoder<T> {
fn encoded_len(&self, mode: Mode) -> usize {
if mode == Mode::Cer {
unimplemented!()
}
let len = self.slice.as_ref().len();
self.tag.encoded_len() + Length::Definite(len).encoded_len() + len
}
fn write_encoded<W: io::Write>(
&self,
mode: Mode,
target: &mut W
) -> Result<(), io::Error> {
if mode == Mode::Cer {
unimplemented!()
}
self.tag.write_encoded(false, target)?;
Length::Definite(self.slice.as_ref().len()).write_encoded(target)?;
target.write_all(self.slice.as_ref())
}
}
//------------ WrappingOctetStringEncoder ------------------------------------
/// A value encoder that wraps the encoded inner values into an octet string.
///
/// You can get a value of this type from octet string’s [`encode_wrapped`]
/// method.
///
/// [`encode_wrapped`]: struct.OctetString.html#method.encode_wrapped
pub struct WrappingOctetStringEncoder<V: encode::Values> {
/// The value to wrap in the octet string.
values: V,
/// The mode to encode those values in.
mode: Mode
}
impl<V: encode::Values> WrappingOctetStringEncoder<V> {
/// Creates a new value from the mode and inner values.
fn new(mode: Mode, values: V) -> Self {
WrappingOctetStringEncoder { values, mode }
}
}
//--- encode::Values
impl<V: encode::Values> encode::Values for WrappingOctetStringEncoder<V> {
fn encoded_len(&self, mode: Mode) -> usize {
if mode == Mode::Cer {
unimplemented!()
}
encode::total_encoded_len(
Tag::OCTET_STRING,
self.values.encoded_len(self.mode)
)
}
fn write_encoded<W: io::Write>(
&self,
mode: Mode,
target: &mut W
) -> Result<(), io::Error> {
if mode == Mode::Cer {
unimplemented!()
}
encode::write_header(
target,
Tag::OCTET_STRING,
false,
self.values.encoded_len(self.mode))?;
self.values.write_encoded(self.mode, target)
}
}
//------------ Tests ---------------------------------------------------------
#[cfg(test)]
mod tests {
use crate::encode::{Values, PrimitiveContent};
use super::*;
#[test]
fn take_from_ber() {
// D .. definite constructed
// I .. indefinied constructed
// p .. primitive
// D(p)
assert_eq!(
decode::Constructed::decode(
b"\x24\x04\
\x04\x02ab".into_source(),
Mode::Ber,
|cons| {
OctetString::take_from(cons)
}
).unwrap().to_bytes(),
"ab"
);
// D(pp)
assert_eq!(
decode::Constructed::decode(
b"\x24\x06\
\x04\x01a\
\x04\x01b".into_source(),
Mode::Ber,
|cons| {
OctetString::take_from(cons)
}
).unwrap().to_bytes(),
"ab"
);
// D(I(p))
assert_eq!(
decode::Constructed::decode(
b"\x24\x08\
\x24\x80\
\x04\x02ab\
\0\0".into_source(),
Mode::Ber,
|cons| {
OctetString::take_from(cons)
}
).unwrap().to_bytes(),
"ab"
);
// I(p)
assert_eq!(
decode::Constructed::decode(
b"\x24\x80\
\x04\x02ab\
\0\0".into_source(),
Mode::Ber,
|cons| {
OctetString::take_from(cons)
}
).unwrap().to_bytes(),
"ab"
);
// D(pI(p))
assert_eq!(
decode::Constructed::decode(
b"\x24\x0a\
\x04\x01a\
\x24\x80\
\x04\x01b\
\0\0".into_source(),
Mode::Ber,
|cons| {
OctetString::take_from(cons)
}
).unwrap().to_bytes(),
"ab"
);
}
#[test]
fn encode_wrapped() {
let mut v = Vec::new();
let enc = OctetString::encode_wrapped(Mode::Der, true.encode());
enc.write_encoded(Mode::Der, &mut v).unwrap();
// 4, 3 OctetString with content length 3
// 1, 1, 255 Boolean, length 1, Value true
assert_eq!(vec![4, 3, 1, 1, 255], v);
let l = enc.encoded_len(Mode::Der);
assert_eq!(l, v.len());
}
}