aerogramme/src/imap/mailbox_view.rs

1368 lines
45 KiB
Rust

use std::borrow::Cow;
use std::iter::zip;
use std::num::NonZeroU32;
use std::sync::Arc;
use anyhow::{anyhow, bail, Error, Result};
use boitalettres::proto::res::body::Data as Body;
use chrono::{Offset, TimeZone, Utc};
use futures::stream::{FuturesOrdered, StreamExt};
use imap_codec::types::address::Address;
use imap_codec::types::body::{BasicFields, Body as FetchBody, BodyStructure, SpecificFields};
use imap_codec::types::core::{AString, Atom, IString, NString};
use imap_codec::types::datetime::MyDateTime;
use imap_codec::types::envelope::Envelope;
use imap_codec::types::fetch_attributes::{
FetchAttribute, MacroOrFetchAttributes, Section as FetchSection,
};
use imap_codec::types::flag::{Flag, StoreResponse, StoreType};
use imap_codec::types::response::{Code, Data, MessageAttribute, Status};
use imap_codec::types::sequence::{self, SequenceSet};
use eml_codec::{
header, imf, mime,
mime::r#type::Deductible,
part::{composite::Message, AnyPart},
};
use crate::cryptoblob::Key;
use crate::mail::mailbox::{MailMeta, Mailbox};
use crate::mail::uidindex::{ImapUid, ImapUidvalidity, UidIndex};
use crate::mail::unique_ident::UniqueIdent;
const DEFAULT_FLAGS: [Flag; 5] = [
Flag::Seen,
Flag::Answered,
Flag::Flagged,
Flag::Deleted,
Flag::Draft,
];
enum FetchedMail<'a> {
Partial(imf::Imf<'a>),
Full(AnyPart<'a>),
}
impl<'a> FetchedMail<'a> {
fn new_from_message(msg: Message<'a>) -> Self {
FetchedMail::Full(AnyPart::Msg(msg))
}
/*fn new_from_header(hdr: imf::Imf<'a>) -> Self {
FetchedMail::Partial(hdr)
}*/
fn as_anypart(&self) -> Result<&AnyPart<'a>> {
match self {
FetchedMail::Full(x) => Ok(&x),
_ => bail!("The full message must be fetched, not only its headers"),
}
}
fn as_full(&self) -> Result<&Message<'a>> {
match self {
FetchedMail::Full(AnyPart::Msg(x)) => Ok(&x),
_ => bail!("The full message must be fetched, not only its headers AND it must be an AnyPart::Msg."),
}
}
fn imf(&self) -> &imf::Imf<'a> {
match self {
FetchedMail::Full(AnyPart::Msg(x)) => &x.imf,
FetchedMail::Partial(x) => &x,
_ => panic!("Can't contain AnyPart that is not a message"),
}
}
}
pub struct AttributesProxy {
attrs: Vec<FetchAttribute>,
}
impl AttributesProxy {
fn new(attrs: &MacroOrFetchAttributes, is_uid_fetch: bool) -> Self {
// Expand macros
let mut fetch_attrs = match attrs {
MacroOrFetchAttributes::Macro(m) => m.expand(),
MacroOrFetchAttributes::FetchAttributes(a) => a.clone(),
};
// Handle uids
if is_uid_fetch && !fetch_attrs.contains(&FetchAttribute::Uid) {
fetch_attrs.push(FetchAttribute::Uid);
}
Self { attrs: fetch_attrs }
}
fn need_body(&self) -> bool {
self.attrs.iter().any(|x| {
matches!(
x,
FetchAttribute::Body
| FetchAttribute::BodyExt { .. }
| FetchAttribute::Rfc822
| FetchAttribute::Rfc822Text
| FetchAttribute::BodyStructure
)
})
}
}
pub struct MailIdentifiers {
i: NonZeroU32,
uid: ImapUid,
uuid: UniqueIdent,
}
struct MailIdentifiersList(Vec<MailIdentifiers>);
impl MailIdentifiersList {
fn uuids(&self) -> Vec<UniqueIdent> {
self.0.iter().map(|mi| mi.uuid).collect()
}
}
pub struct MailView<'a> {
ids: &'a MailIdentifiers,
meta: &'a MailMeta,
flags: &'a Vec<String>,
content: FetchedMail<'a>,
add_seen: bool,
}
impl<'a> MailView<'a> {
fn uid(&self) -> MessageAttribute {
MessageAttribute::Uid(self.ids.uid)
}
fn flags(&self) -> MessageAttribute {
MessageAttribute::Flags(
self.flags
.iter()
.filter_map(|f| string_to_flag(f))
.collect(),
)
}
fn rfc_822_size(&self) -> MessageAttribute {
MessageAttribute::Rfc822Size(self.meta.rfc822_size as u32)
}
fn rfc_822_header(&self) -> MessageAttribute {
MessageAttribute::Rfc822Header(NString(
self.meta
.headers
.to_vec()
.try_into()
.ok()
.map(IString::Literal),
))
}
fn rfc_822_text(&self) -> Result<MessageAttribute> {
Ok(MessageAttribute::Rfc822Text(NString(
self.content
.as_full()?
.raw_body
.try_into()
.ok()
.map(IString::Literal),
)))
}
fn rfc822(&self) -> Result<MessageAttribute> {
Ok(MessageAttribute::Rfc822(NString(
self.content
.as_full()?
.raw_body
.clone()
.try_into()
.ok()
.map(IString::Literal),
)))
}
fn envelope(&self) -> MessageAttribute {
MessageAttribute::Envelope(message_envelope(self.content.imf()))
}
fn body(&self) -> Result<MessageAttribute> {
Ok(MessageAttribute::Body(build_imap_email_struct(
self.content.as_full()?.child.as_ref(),
)?))
}
fn body_structure(&self) -> Result<MessageAttribute> {
Ok(MessageAttribute::Body(build_imap_email_struct(
self.content.as_full()?.child.as_ref(),
)?))
}
/// maps to BODY[<section>]<<partial>> and BODY.PEEK[<section>]<<partial>>
/// peek does not implicitly set the \Seen flag
/// eg. BODY[HEADER.FIELDS (DATE FROM)]
/// eg. BODY[]<0.2048>
fn body_ext(
&mut self,
section: &Option<FetchSection>,
partial: &Option<(u32, NonZeroU32)>,
peek: &bool,
) -> Result<MessageAttribute> {
// Extract message section
let text = get_message_section(self.content.as_anypart()?, section)?;
let seen_flag = Flag::Seen.to_string();
if !peek && !self.flags.iter().any(|x| *x == seen_flag) {
// Add \Seen flag
//self.mailbox.add_flags(uuid, &[seen_flag]).await?;
self.add_seen = true;
}
// Handle <<partial>> which cut the message bytes
let (text, origin) = apply_partial(partial, &text);
let data = NString(text.to_vec().try_into().ok().map(IString::Literal));
return Ok(MessageAttribute::BodyExt {
section: section.clone(),
origin,
data,
});
}
fn internal_date(&self) -> Result<MessageAttribute> {
let dt = Utc
.fix()
.timestamp_opt(i64::try_from(self.meta.internaldate / 1000)?, 0)
.earliest()
.ok_or(anyhow!("Unable to parse internal date"))?;
Ok(MessageAttribute::InternalDate(MyDateTime(dt)))
}
fn filter(&mut self, ap: &AttributesProxy) -> Result<Body> {
let res_attrs = ap
.attrs
.iter()
.map(|attr| match attr {
FetchAttribute::Uid => Ok(self.uid()),
FetchAttribute::Flags => Ok(self.flags()),
FetchAttribute::Rfc822Size => Ok(self.rfc_822_size()),
FetchAttribute::Rfc822Header => Ok(self.rfc_822_header()),
FetchAttribute::Rfc822Text => self.rfc_822_text(),
FetchAttribute::Rfc822 => self.rfc822(),
FetchAttribute::Envelope => Ok(self.envelope()),
FetchAttribute::Body => self.body(),
FetchAttribute::BodyStructure => self.body_structure(),
FetchAttribute::BodyExt {
section,
partial,
peek,
} => self.body_ext(section, partial, peek),
FetchAttribute::InternalDate => self.internal_date(),
})
.collect::<Result<Vec<_>, _>>()?;
Ok(Body::Data(Data::Fetch {
seq_or_uid: self.ids.i,
attributes: res_attrs,
}))
}
}
fn apply_partial<'a>(
partial: &'_ Option<(u32, NonZeroU32)>,
text: &'a [u8],
) -> (&'a [u8], Option<u32>) {
match partial {
Some((begin, len)) => {
if *begin as usize > text.len() {
(&[][..], Some(*begin))
} else if (begin + len.get()) as usize >= text.len() {
(&text[*begin as usize..], Some(*begin))
} else {
(
&text[*begin as usize..(begin + len.get()) as usize],
Some(*begin),
)
}
}
None => (&text[..], None),
}
}
pub struct BodyIdentifier<'a> {
msg_uuid: &'a UniqueIdent,
msg_key: &'a Key,
}
#[derive(Default)]
pub struct MailSelectionBuilder<'a> {
//attrs: AttributeProxy,
mail_count: usize,
need_body: bool,
mi: &'a [MailIdentifiers],
meta: &'a [MailMeta],
flags: &'a [&'a Vec<String>],
bodies: &'a [Vec<u8>],
}
impl<'a> MailSelectionBuilder<'a> {
fn new(need_body: bool, mail_count: usize) -> Self {
Self {
mail_count,
need_body,
..MailSelectionBuilder::default()
}
}
fn with_mail_identifiers(&mut self, mi: &'a [MailIdentifiers]) -> &mut Self {
self.mi = mi;
self
}
fn with_metadata(&mut self, meta: &'a [MailMeta]) -> &mut Self {
self.meta = meta;
self
}
fn with_flags(&mut self, flags: &'a [&'a Vec<String>]) -> &mut Self {
self.flags = flags;
self
}
fn bodies_to_collect(&self) -> Vec<BodyIdentifier> {
if !self.need_body {
return vec![];
}
zip(self.mi, self.meta)
.map(|(mi, meta)| BodyIdentifier {
msg_uuid: &mi.uuid,
msg_key: &meta.message_key,
})
.collect::<Vec<_>>()
}
fn with_bodies(&mut self, rbodies: &'a [Vec<u8>]) -> &mut Self {
self.bodies = rbodies;
self
}
fn build(&self) -> Result<Vec<MailView<'a>>> {
let mut bodies = vec![];
if !self.need_body {
for m in self.meta.iter() {
let (_, hdrs) =
eml_codec::parse_imf(&m.headers).or(Err(anyhow!("Invalid mail headers")))?;
bodies.push(FetchedMail::Partial(hdrs));
}
} else {
for rb in self.bodies.iter() {
let (_, p) = eml_codec::parse_message(&rb).or(Err(anyhow!("Invalid mail body")))?;
bodies.push(FetchedMail::new_from_message(p));
}
}
if self.mi.len() != self.mail_count && self.meta.len() != self.mail_count
|| self.flags.len() != self.mail_count
|| bodies.len() != self.mail_count
{
return Err(anyhow!("Can't build a mail view selection as parts were not correctly registered into the builder."));
}
Ok(zip(self.mi, zip(self.meta, zip(self.flags, bodies)))
.map(|(ids, (meta, (flags, content)))| MailView {
ids,
meta,
flags,
content,
add_seen: false,
})
.collect())
}
}
/// A MailboxView is responsible for giving the client the information
/// it needs about a mailbox, such as an initial summary of the mailbox's
/// content and continuous updates indicating when the content
/// of the mailbox has been changed.
/// To do this, it keeps a variable `known_state` that corresponds to
/// what the client knows, and produces IMAP messages to be sent to the
/// client that go along updates to `known_state`.
pub struct MailboxView {
pub(crate) mailbox: Arc<Mailbox>,
known_state: UidIndex,
}
impl MailboxView {
/// Creates a new IMAP view into a mailbox.
/// Generates the necessary IMAP messages so that the client
/// has a satisfactory summary of the current mailbox's state.
/// These are the messages that are sent in response to a SELECT command.
pub async fn new(mailbox: Arc<Mailbox>) -> Result<(Self, Vec<Body>)> {
let state = mailbox.current_uid_index().await;
let new_view = Self {
mailbox,
known_state: state,
};
let mut data = Vec::<Body>::new();
data.push(new_view.exists_status()?);
data.push(new_view.recent_status()?);
data.extend(new_view.flags_status()?.into_iter());
data.push(new_view.uidvalidity_status()?);
data.push(new_view.uidnext_status()?);
Ok((new_view, data))
}
/// Produces a set of IMAP responses describing the change between
/// what the client knows and what is actually in the mailbox.
/// This does NOT trigger a sync, it bases itself on what is currently
/// loaded in RAM by Bayou.
pub async fn update(&mut self) -> Result<Vec<Body>> {
let new_view = MailboxView {
mailbox: self.mailbox.clone(),
known_state: self.mailbox.current_uid_index().await,
};
let mut data = Vec::<Body>::new();
// Calculate diff between two mailbox states
// See example in IMAP RFC in section on NOOP command:
// we want to produce something like this:
// C: a047 NOOP
// S: * 22 EXPUNGE
// S: * 23 EXISTS
// S: * 14 FETCH (UID 1305 FLAGS (\Seen \Deleted))
// S: a047 OK Noop completed
// In other words:
// - notify client of expunged mails
// - if new mails arrived, notify client of number of existing mails
// - if flags changed for existing mails, tell client
// (for this last step: if uidvalidity changed, do nothing,
// just notify of new uidvalidity and they will resync)
// - notify client of expunged mails
let mut n_expunge = 0;
for (i, (_uid, uuid)) in self.known_state.idx_by_uid.iter().enumerate() {
if !new_view.known_state.table.contains_key(uuid) {
data.push(Body::Data(Data::Expunge(
NonZeroU32::try_from((i + 1 - n_expunge) as u32).unwrap(),
)));
n_expunge += 1;
}
}
// - if new mails arrived, notify client of number of existing mails
if new_view.known_state.table.len() != self.known_state.table.len() - n_expunge
|| new_view.known_state.uidvalidity != self.known_state.uidvalidity
{
data.push(new_view.exists_status()?);
}
if new_view.known_state.uidvalidity != self.known_state.uidvalidity {
// TODO: do we want to push less/more info than this?
data.push(new_view.uidvalidity_status()?);
data.push(new_view.uidnext_status()?);
} else {
// - if flags changed for existing mails, tell client
for (i, (_uid, uuid)) in new_view.known_state.idx_by_uid.iter().enumerate() {
let old_mail = self.known_state.table.get(uuid);
let new_mail = new_view.known_state.table.get(uuid);
if old_mail.is_some() && old_mail != new_mail {
if let Some((uid, flags)) = new_mail {
data.push(Body::Data(Data::Fetch {
seq_or_uid: NonZeroU32::try_from((i + 1) as u32).unwrap(),
attributes: vec![
MessageAttribute::Uid(*uid),
MessageAttribute::Flags(
flags.iter().filter_map(|f| string_to_flag(f)).collect(),
),
],
}));
}
}
}
}
*self = new_view;
Ok(data)
}
pub async fn store(
&mut self,
sequence_set: &SequenceSet,
kind: &StoreType,
_response: &StoreResponse,
flags: &[Flag],
is_uid_store: &bool,
) -> Result<Vec<Body>> {
self.mailbox.opportunistic_sync().await?;
let flags = flags.iter().map(|x| x.to_string()).collect::<Vec<_>>();
let mails = self.get_mail_ids(sequence_set, *is_uid_store)?;
for mi in mails.iter() {
match kind {
StoreType::Add => {
self.mailbox.add_flags(mi.uuid, &flags[..]).await?;
}
StoreType::Remove => {
self.mailbox.del_flags(mi.uuid, &flags[..]).await?;
}
StoreType::Replace => {
self.mailbox.set_flags(mi.uuid, &flags[..]).await?;
}
}
}
// @TODO: handle _response
self.update().await
}
pub async fn expunge(&mut self) -> Result<Vec<Body>> {
self.mailbox.opportunistic_sync().await?;
let deleted_flag = Flag::Deleted.to_string();
let state = self.mailbox.current_uid_index().await;
let msgs = state
.table
.iter()
.filter(|(_uuid, (_uid, flags))| flags.iter().any(|x| *x == deleted_flag))
.map(|(uuid, _)| *uuid);
for msg in msgs {
self.mailbox.delete(msg).await?;
}
self.update().await
}
pub async fn copy(
&self,
sequence_set: &SequenceSet,
to: Arc<Mailbox>,
is_uid_copy: &bool,
) -> Result<(ImapUidvalidity, Vec<(ImapUid, ImapUid)>)> {
let mails = self.get_mail_ids(sequence_set, *is_uid_copy)?;
let mut new_uuids = vec![];
for mi in mails.iter() {
new_uuids.push(to.copy_from(&self.mailbox, mi.uuid).await?);
}
let mut ret = vec![];
let to_state = to.current_uid_index().await;
for (mi, new_uuid) in mails.iter().zip(new_uuids.iter()) {
let dest_uid = to_state
.table
.get(new_uuid)
.ok_or(anyhow!("copied mail not in destination mailbox"))?
.0;
ret.push((mi.uid, dest_uid));
}
Ok((to_state.uidvalidity, ret))
}
/// Looks up state changes in the mailbox and produces a set of IMAP
/// responses describing the new state.
pub async fn fetch(
&self,
sequence_set: &SequenceSet,
attributes: &MacroOrFetchAttributes,
is_uid_fetch: &bool,
) -> Result<Vec<Body>> {
let ap = AttributesProxy::new(attributes, *is_uid_fetch);
// Prepare data
let mids = MailIdentifiersList(self.get_mail_ids(sequence_set, *is_uid_fetch)?);
let mail_count = mids.0.len();
let uuids = mids.uuids();
let meta = self.mailbox.fetch_meta(&uuids).await?;
let flags = uuids
.iter()
.map(|uuid| {
self.known_state
.table
.get(uuid)
.map(|(_uuid, f)| f)
.ok_or(anyhow!("missing email from the flag table"))
})
.collect::<Result<Vec<_>, _>>()?;
// Start filling data to build the view
let mut selection = MailSelectionBuilder::new(ap.need_body(), mail_count);
selection
.with_mail_identifiers(&mids.0)
.with_metadata(&meta)
.with_flags(&flags);
// Asynchronously fetch full bodies (if needed)
let btc = selection.bodies_to_collect();
let future_bodies = btc
.iter()
.map(|bi| async move {
let body = self.mailbox.fetch_full(*bi.msg_uuid, bi.msg_key).await?;
Ok::<_, anyhow::Error>(body)
})
.collect::<FuturesOrdered<_>>();
let bodies = future_bodies
.collect::<Vec<_>>()
.await
.into_iter()
.collect::<Result<Vec<_>, _>>()?;
// Add bodies
selection.with_bodies(bodies.as_slice());
// Build mail selection views
let mut views = selection.build()?;
// Filter views to build the result
let ret = views
.iter_mut()
.filter_map(|mv| mv.filter(&ap).ok())
.collect::<Vec<_>>();
// Register seen flags
let future_flags = views
.iter()
.filter(|mv| mv.add_seen)
.map(|mv| async move {
let seen_flag = Flag::Seen.to_string();
self.mailbox.add_flags(mv.ids.uuid, &[seen_flag]).await?;
Ok::<_, anyhow::Error>(())
})
.collect::<FuturesOrdered<_>>();
future_flags
.collect::<Vec<_>>()
.await
.into_iter()
.collect::<Result<_, _>>()?;
Ok(ret)
}
// ----
// Gets the IMAP ID, the IMAP UIDs and, the Aerogramme UUIDs of mails identified by a SequenceSet of
// sequence numbers (~ IMAP selector)
fn get_mail_ids(
&self,
sequence_set: &SequenceSet,
by_uid: bool,
) -> Result<Vec<MailIdentifiers>> {
let mail_vec = self
.known_state
.idx_by_uid
.iter()
.map(|(uid, uuid)| (*uid, *uuid))
.collect::<Vec<_>>();
let mut mails = vec![];
if by_uid {
if mail_vec.is_empty() {
return Ok(vec![]);
}
let iter_strat = sequence::Strategy::Naive {
largest: mail_vec.last().unwrap().0,
};
let mut i = 0;
for uid in sequence_set.iter(iter_strat) {
while mail_vec.get(i).map(|mail| mail.0 < uid).unwrap_or(false) {
i += 1;
}
if let Some(mail) = mail_vec.get(i) {
if mail.0 == uid {
mails.push(MailIdentifiers {
i: NonZeroU32::try_from(i as u32 + 1).unwrap(),
uid: mail.0,
uuid: mail.1,
});
}
} else {
break;
}
}
} else {
if mail_vec.is_empty() {
bail!("No such message (mailbox is empty)");
}
let iter_strat = sequence::Strategy::Naive {
largest: NonZeroU32::try_from((mail_vec.len()) as u32).unwrap(),
};
for i in sequence_set.iter(iter_strat) {
if let Some(mail) = mail_vec.get(i.get() as usize - 1) {
mails.push(MailIdentifiers {
i,
uid: mail.0,
uuid: mail.1,
});
} else {
bail!("No such mail: {}", i);
}
}
}
Ok(mails)
}
// ----
/// Produce an OK [UIDVALIDITY _] message corresponding to `known_state`
fn uidvalidity_status(&self) -> Result<Body> {
let uid_validity = Status::ok(
None,
Some(Code::UidValidity(self.uidvalidity())),
"UIDs valid",
)
.map_err(Error::msg)?;
Ok(Body::Status(uid_validity))
}
pub(crate) fn uidvalidity(&self) -> ImapUidvalidity {
self.known_state.uidvalidity
}
/// Produce an OK [UIDNEXT _] message corresponding to `known_state`
fn uidnext_status(&self) -> Result<Body> {
let next_uid = Status::ok(
None,
Some(Code::UidNext(self.uidnext())),
"Predict next UID",
)
.map_err(Error::msg)?;
Ok(Body::Status(next_uid))
}
pub(crate) fn uidnext(&self) -> ImapUid {
self.known_state.uidnext
}
/// Produce an EXISTS message corresponding to the number of mails
/// in `known_state`
fn exists_status(&self) -> Result<Body> {
Ok(Body::Data(Data::Exists(self.exists()?)))
}
pub(crate) fn exists(&self) -> Result<u32> {
Ok(u32::try_from(self.known_state.idx_by_uid.len())?)
}
/// Produce a RECENT message corresponding to the number of
/// recent mails in `known_state`
fn recent_status(&self) -> Result<Body> {
Ok(Body::Data(Data::Recent(self.recent()?)))
}
pub(crate) fn recent(&self) -> Result<u32> {
let recent = self
.known_state
.idx_by_flag
.get(&"\\Recent".to_string())
.map(|os| os.len())
.unwrap_or(0);
Ok(u32::try_from(recent)?)
}
/// Produce a FLAGS and a PERMANENTFLAGS message that indicates
/// the flags that are in `known_state` + default flags
fn flags_status(&self) -> Result<Vec<Body>> {
let mut flags: Vec<Flag> = self
.known_state
.idx_by_flag
.flags()
.filter_map(|f| string_to_flag(f))
.collect();
for f in DEFAULT_FLAGS.iter() {
if !flags.contains(f) {
flags.push(f.clone());
}
}
let mut ret = vec![Body::Data(Data::Flags(flags.clone()))];
flags.push(Flag::Permanent);
let permanent_flags =
Status::ok(None, Some(Code::PermanentFlags(flags)), "Flags permitted")
.map_err(Error::msg)?;
ret.push(Body::Status(permanent_flags));
Ok(ret)
}
pub(crate) fn unseen_count(&self) -> usize {
let total = self.known_state.table.len();
let seen = self
.known_state
.idx_by_flag
.get(&Flag::Seen.to_string())
.map(|x| x.len())
.unwrap_or(0);
total - seen
}
}
fn string_to_flag(f: &str) -> Option<Flag> {
match f.chars().next() {
Some('\\') => match f {
"\\Seen" => Some(Flag::Seen),
"\\Answered" => Some(Flag::Answered),
"\\Flagged" => Some(Flag::Flagged),
"\\Deleted" => Some(Flag::Deleted),
"\\Draft" => Some(Flag::Draft),
"\\Recent" => Some(Flag::Recent),
_ => match Atom::try_from(f.strip_prefix('\\').unwrap().to_string()) {
Err(_) => {
tracing::error!(flag=%f, "Unable to encode flag as IMAP atom");
None
}
Ok(a) => Some(Flag::Extension(a)),
},
},
Some(_) => match Atom::try_from(f.to_string()) {
Err(_) => {
tracing::error!(flag=%f, "Unable to encode flag as IMAP atom");
None
}
Ok(a) => Some(Flag::Keyword(a)),
},
None => None,
}
}
/// Envelope rules are defined in RFC 3501, section 7.4.2
/// https://datatracker.ietf.org/doc/html/rfc3501#section-7.4.2
///
/// Some important notes:
///
/// If the Sender or Reply-To lines are absent in the [RFC-2822]
/// header, or are present but empty, the server sets the
/// corresponding member of the envelope to be the same value as
/// the from member (the client is not expected to know to do
/// this). Note: [RFC-2822] requires that all messages have a valid
/// From header. Therefore, the from, sender, and reply-to
/// members in the envelope can not be NIL.
///
/// If the Date, Subject, In-Reply-To, and Message-ID header lines
/// are absent in the [RFC-2822] header, the corresponding member
/// of the envelope is NIL; if these header lines are present but
/// empty the corresponding member of the envelope is the empty
/// string.
//@FIXME return an error if the envelope is invalid instead of panicking
//@FIXME some fields must be defaulted if there are not set.
fn message_envelope(msg: &imf::Imf) -> Envelope {
let from = msg.from.iter().map(convert_mbx).collect::<Vec<_>>();
Envelope {
date: NString(
msg.date
.as_ref()
.map(|d| IString::try_from(d.to_rfc3339()).unwrap()),
),
subject: NString(
msg.subject
.as_ref()
.map(|d| IString::try_from(d.to_string()).unwrap()),
),
sender: msg
.sender
.as_ref()
.map(|v| vec![convert_mbx(v)])
.unwrap_or(from.clone()),
reply_to: if msg.reply_to.is_empty() {
from.clone()
} else {
convert_addresses(&msg.reply_to)
},
from,
to: convert_addresses(&msg.to),
cc: convert_addresses(&msg.cc),
bcc: convert_addresses(&msg.bcc),
in_reply_to: NString(
msg.in_reply_to
.iter()
.next()
.map(|d| IString::try_from(d.to_string()).unwrap()),
),
message_id: NString(
msg.msg_id
.as_ref()
.map(|d| IString::try_from(d.to_string()).unwrap()),
),
}
}
fn convert_addresses(addrlist: &Vec<imf::address::AddressRef>) -> Vec<Address> {
let mut acc = vec![];
for item in addrlist {
match item {
imf::address::AddressRef::Single(a) => acc.push(convert_mbx(a)),
imf::address::AddressRef::Many(l) => acc.extend(l.participants.iter().map(convert_mbx)),
}
}
return acc;
}
fn convert_mbx(addr: &imf::mailbox::MailboxRef) -> Address {
Address::new(
NString(
addr.name
.as_ref()
.map(|x| IString::try_from(x.to_string()).unwrap()),
),
// SMTP at-domain-list (source route) seems obsolete since at least 1991
// https://www.mhonarc.org/archive/html/ietf-822/1991-06/msg00060.html
NString(None),
NString(Some(
IString::try_from(addr.addrspec.local_part.to_string()).unwrap(),
)),
NString(Some(
IString::try_from(addr.addrspec.domain.to_string()).unwrap(),
)),
)
}
/*
--CAPTURE--
b fetch 29878:29879 (BODY)
* 29878 FETCH (BODY (("text" "plain" ("charset" "utf-8") NIL NIL "quoted-printable" 3264 82)("text" "html" ("charset" "utf-8") NIL NIL "quoted-printable" 31834 643) "alternative"))
* 29879 FETCH (BODY ("text" "html" ("charset" "us-ascii") NIL NIL "7bit" 4107 131))
^^^^^^^^^^^^^^^^^^^^^^ ^^^ ^^^ ^^^^^^ ^^^^ ^^^
| | | | | | number of lines
| | | | | size
| | | | content transfer encoding
| | | description
| | id
| parameter list
b OK Fetch completed (0.001 + 0.000 secs).
*/
fn build_imap_email_struct<'a>(part: &AnyPart<'a>) -> Result<BodyStructure> {
match part {
AnyPart::Mult(x) => {
let itype = &x.mime.interpreted_type;
let subtype = IString::try_from(itype.subtype.to_string())
.unwrap_or(unchecked_istring("alternative"));
Ok(BodyStructure::Multi {
bodies: x
.children
.iter()
.filter_map(|inner| build_imap_email_struct(&inner).ok())
.collect(),
subtype,
extension_data: None,
/*Some(MultipartExtensionData {
parameter_list: vec![],
disposition: None,
language: None,
location: None,
extension: vec![],
})*/
})
}
AnyPart::Txt(x) => {
let mut basic = basic_fields(&x.mime.fields, x.body.len())?;
// Get the interpreted content type, set it
let itype = match &x.mime.interpreted_type {
Deductible::Inferred(v) | Deductible::Explicit(v) => v,
};
let subtype =
IString::try_from(itype.subtype.to_string()).unwrap_or(unchecked_istring("plain"));
// Add charset to the list of parameters if we know it has been inferred as it will be
// missing from the parsed content.
if let Deductible::Inferred(charset) = &itype.charset {
basic.parameter_list.push((
unchecked_istring("charset"),
IString::try_from(charset.to_string()).unwrap_or(unchecked_istring("us-ascii")),
));
}
Ok(BodyStructure::Single {
body: FetchBody {
basic,
specific: SpecificFields::Text {
subtype,
number_of_lines: nol(x.body),
},
},
extension: None,
})
}
AnyPart::Bin(x) => {
let basic = basic_fields(&x.mime.fields, x.body.len())?;
let default = mime::r#type::NaiveType {
main: &b"application"[..],
sub: &b"octet-stream"[..],
params: vec![],
};
let ct = x.mime.fields.ctype.as_ref().unwrap_or(&default);
let type_ = IString::try_from(String::from_utf8_lossy(ct.main).to_string()).or(Err(
anyhow!("Unable to build IString from given Content-Type type given"),
))?;
let subtype =
IString::try_from(String::from_utf8_lossy(ct.sub).to_string()).or(Err(anyhow!(
"Unable to build IString from given Content-Type subtype given"
)))?;
Ok(BodyStructure::Single {
body: FetchBody {
basic,
specific: SpecificFields::Basic { type_, subtype },
},
extension: None,
})
}
AnyPart::Msg(x) => {
let basic = basic_fields(&x.mime.fields, x.raw_part.len())?;
Ok(BodyStructure::Single {
body: FetchBody {
basic,
specific: SpecificFields::Message {
envelope: message_envelope(&x.imf),
body_structure: Box::new(build_imap_email_struct(x.child.as_ref())?),
number_of_lines: nol(x.raw_part),
},
},
extension: None,
})
}
}
}
fn nol(input: &[u8]) -> u32 {
input
.iter()
.filter(|x| **x == b'\n')
.count()
.try_into()
.unwrap_or(0)
}
/// s is set to static to ensure that only compile time values
/// checked by developpers are passed.
fn unchecked_istring(s: &'static str) -> IString {
IString::try_from(s).expect("this value is expected to be a valid imap-codec::IString")
}
fn basic_fields(m: &mime::NaiveMIME, sz: usize) -> Result<BasicFields> {
let parameter_list = m
.ctype
.as_ref()
.map(|x| {
x.params
.iter()
.map(|p| {
(
IString::try_from(String::from_utf8_lossy(p.name).to_string()),
IString::try_from(p.value.to_string()),
)
})
.filter(|(k, v)| k.is_ok() && v.is_ok())
.map(|(k, v)| (k.unwrap(), v.unwrap()))
.collect()
})
.unwrap_or(vec![]);
Ok(BasicFields {
parameter_list,
id: NString(
m.id.as_ref()
.and_then(|ci| IString::try_from(ci.to_string()).ok()),
),
description: NString(
m.description
.as_ref()
.and_then(|cd| IString::try_from(cd.to_string()).ok()),
),
content_transfer_encoding: match m.transfer_encoding {
mime::mechanism::Mechanism::_8Bit => unchecked_istring("8bit"),
mime::mechanism::Mechanism::Binary => unchecked_istring("binary"),
mime::mechanism::Mechanism::QuotedPrintable => unchecked_istring("quoted-printable"),
mime::mechanism::Mechanism::Base64 => unchecked_istring("base64"),
_ => unchecked_istring("7bit"),
},
// @FIXME we can't compute the size of the message currently...
size: u32::try_from(sz)?,
})
}
/// Extract message section for section identifier passed by the FETCH BODY[<section>]<<partial>>
/// request
///
/// Example of message sections:
///
/// ```
/// HEADER ([RFC-2822] header of the message)
/// TEXT ([RFC-2822] text body of the message) MULTIPART/MIXED
/// 1 TEXT/PLAIN
/// 2 APPLICATION/OCTET-STREAM
/// 3 MESSAGE/RFC822
/// 3.HEADER ([RFC-2822] header of the message)
/// 3.TEXT ([RFC-2822] text body of the message) MULTIPART/MIXED
/// 3.1 TEXT/PLAIN
/// 3.2 APPLICATION/OCTET-STREAM
/// 4 MULTIPART/MIXED
/// 4.1 IMAGE/GIF
/// 4.1.MIME ([MIME-IMB] header for the IMAGE/GIF)
/// 4.2 MESSAGE/RFC822
/// 4.2.HEADER ([RFC-2822] header of the message)
/// 4.2.TEXT ([RFC-2822] text body of the message) MULTIPART/MIXED
/// 4.2.1 TEXT/PLAIN
/// 4.2.2 MULTIPART/ALTERNATIVE
/// 4.2.2.1 TEXT/PLAIN
/// 4.2.2.2 TEXT/RICHTEXT
/// ```
fn get_message_section<'a>(
parsed: &'a AnyPart<'a>,
section: &Option<FetchSection>,
) -> Result<Cow<'a, [u8]>> {
let msg = parsed
.as_message()
.ok_or(anyhow!("Part must be a message"))?;
match section {
Some(FetchSection::Text(None)) => Ok(msg.raw_body.into()),
Some(FetchSection::Text(Some(part))) => {
map_subpart(parsed, part.0.as_slice(), |part_msg| {
Ok(part_msg
.as_message()
.ok_or(Error::msg(
"Not a message/rfc822 part while expected by request (TEXT)",
))?
.raw_body
.into())
})
}
Some(FetchSection::Header(part)) => map_subpart(
parsed,
part.as_ref().map(|p| p.0.as_slice()).unwrap_or(&[]),
|part_msg| {
Ok(part_msg
.as_message()
.ok_or(Error::msg(
"Not a message/rfc822 part while expected by request (HEADER)",
))?
.raw_headers
.into())
},
),
Some(
FetchSection::HeaderFields(part, fields) | FetchSection::HeaderFieldsNot(part, fields),
) => {
let invert = matches!(section, Some(FetchSection::HeaderFieldsNot(_, _)));
let fields = fields
.iter()
.map(|x| match x {
AString::Atom(a) => a.as_bytes(),
AString::String(IString::Literal(l)) => l.as_slice(),
AString::String(IString::Quoted(q)) => q.as_bytes(),
})
.collect::<Vec<_>>();
map_subpart(
parsed,
part.as_ref().map(|p| p.0.as_slice()).unwrap_or(&[]),
|part_msg| {
let mut ret = vec![];
for f in &part_msg.mime().kv {
let (k, v) = match f {
header::Field::Good(header::Kv2(k, v)) => (k, v),
_ => continue,
};
if fields.as_slice().iter().any(|x| (x == k) ^ invert) {
ret.extend(*k);
ret.extend(b": ");
ret.extend(*v);
ret.extend(b"\r\n");
}
}
ret.extend(b"\r\n");
Ok(ret.into())
},
)
}
Some(FetchSection::Part(part)) => map_subpart(parsed, part.0.as_slice(), |part| {
let bytes = match &part {
AnyPart::Txt(p) => p.body,
AnyPart::Bin(p) => p.body,
AnyPart::Msg(p) => p.raw_part,
AnyPart::Mult(_) => bail!("Multipart part has no body"),
};
Ok(bytes.to_vec().into())
}),
Some(FetchSection::Mime(part)) => map_subpart(parsed, part.0.as_slice(), |part| {
let bytes = match &part {
AnyPart::Txt(p) => p.mime.fields.raw,
AnyPart::Bin(p) => p.mime.fields.raw,
AnyPart::Msg(p) => p.mime.fields.raw,
AnyPart::Mult(p) => p.mime.fields.raw,
};
Ok(bytes.to_vec().into())
}),
None => Ok(msg.raw_part.into()),
}
}
/// Fetch a MIME SubPart
///
/// eg. FETCH BODY[4.2.2.1] -> [4, 2, 2, 1]
fn map_subpart<'a, F, R>(part: &AnyPart<'a>, path: &[NonZeroU32], f: F) -> Result<R>
where
F: FnOnce(&AnyPart<'a>) -> Result<R>,
{
if path.is_empty() {
f(part)
} else {
match part {
AnyPart::Mult(x) => map_subpart(
x.children
.get(path[0].get() as usize - 1)
.ok_or(anyhow!("Unable to resolve subpath {:?}, current multipart has only {} elements", path, x.children.len()))?,
&path[1..],
f),
AnyPart::Msg(x) => map_subpart(x.child.as_ref(), path, f),
_ => bail!("You tried to access a subpart on an atomic part (text or binary). Unresolved subpath {:?}", path),
}
}
}
#[cfg(test)]
mod tests {
use super::*;
use crate::cryptoblob;
use crate::mail::unique_ident;
use imap_codec::codec::Encode;
use imap_codec::types::fetch_attributes::Section;
use std::fs;
#[test]
fn mailview_body_ext() -> Result<()> {
let ap = AttributesProxy::new(
&MacroOrFetchAttributes::FetchAttributes(vec![FetchAttribute::BodyExt {
section: Some(Section::Header(None)),
partial: None,
peek: false,
}]),
false,
);
let flags = vec![];
let key = cryptoblob::gen_key();
let meta = MailMeta {
internaldate: 0u64,
headers: vec![],
message_key: key,
rfc822_size: 8usize,
};
let ids = MailIdentifiers {
i: NonZeroU32::MIN,
uid: NonZeroU32::MIN,
uuid: unique_ident::gen_ident(),
};
let rfc822 = b"Subject: hello\r\nFrom: a@a.a\r\nTo: b@b.b\r\nDate: Thu, 12 Oct 2023 08:45:28 +0000\r\n\r\nhello world";
let content = FetchedMail::new_from_message(eml_codec::parse_message(rfc822)?.1);
let mut mv = MailView {
ids: &ids,
content,
meta: &meta,
flags: &flags,
add_seen: false,
};
let res_body = mv.filter(&ap)?;
let fattr = match res_body {
Body::Data(Data::Fetch {
seq_or_uid: _seq,
attributes: attr,
}) => Ok(attr),
_ => Err(anyhow!("Not a fetch body")),
}?;
assert_eq!(fattr.len(), 1);
let (sec, _orig, _data) = match &fattr[0] {
MessageAttribute::BodyExt {
section,
origin,
data,
} => Ok((section, origin, data)),
_ => Err(anyhow!("not a body ext message attribute")),
}?;
assert_eq!(sec.as_ref().unwrap(), &Section::Header(None));
Ok(())
}
/// Future automated test. We use lossy utf8 conversion + lowercase everything,
/// so this test might allow invalid results. But at least it allows us to quickly test a
/// large variety of emails.
/// Keep in mind that special cases must still be tested manually!
#[test]
fn fetch_body() -> Result<()> {
let prefixes = [
/* *** MY OWN DATASET *** */
"tests/emails/dxflrs/0001_simple",
"tests/emails/dxflrs/0002_mime",
"tests/emails/dxflrs/0003_mime-in-mime",
"tests/emails/dxflrs/0004_msg-in-msg",
// eml_codec do not support continuation for the moment
//"tests/emails/dxflrs/0005_mail-parser-readme",
"tests/emails/dxflrs/0006_single-mime",
"tests/emails/dxflrs/0007_raw_msg_in_rfc822",
/* *** (STRANGE) RFC *** */
//"tests/emails/rfc/000", // must return text/enriched, we return text/plain
//"tests/emails/rfc/001", // does not recognize the multipart/external-body, breaks the
// whole parsing
//"tests/emails/rfc/002", // wrong date in email
//"tests/emails/rfc/003", // dovecot fixes \r\r: the bytes number is wrong + text/enriched
/* *** THIRD PARTY *** */
//"tests/emails/thirdparty/000", // dovecot fixes \r\r: the bytes number is wrong
//"tests/emails/thirdparty/001", // same
"tests/emails/thirdparty/002", // same
/* *** LEGACY *** */
//"tests/emails/legacy/000", // same issue with \r\r
];
for pref in prefixes.iter() {
println!("{}", pref);
let txt = fs::read(format!("{}.eml", pref))?;
let exp = fs::read(format!("{}.dovecot.body", pref))?;
let message = eml_codec::parse_message(&txt).unwrap().1;
let mut resp = Vec::new();
MessageAttribute::Body(build_imap_email_struct(&message.child)?)
.encode(&mut resp)
.unwrap();
let resp_str = String::from_utf8_lossy(&resp).to_lowercase();
let exp_no_parenthesis = &exp[1..exp.len() - 1];
let exp_str = String::from_utf8_lossy(exp_no_parenthesis).to_lowercase();
println!("aerogramme: {}\n\ndovecot: {}\n\n", resp_str, exp_str);
//println!("\n\n {} \n\n", String::from_utf8_lossy(&resp));
assert_eq!(resp_str, exp_str);
}
Ok(())
}
}