Parser library for Composable Event Streaming Representation (CESR).
This library is currently under construction.
Example parsing code (top level ACDC, KEL and TEL parsing):
fn verify_acdc(&self, creder: &Creder, quadlets: &AttachedMaterialQuadlets, deep: Option<bool>) -> Result<bool> {
if creder.status()?.is_none() {
return err!(Error::Validation);
};
let vcid = creder.said()?;
let schema = creder.schema()?;
let prov = creder.chains()?;
let event = self.store.get_latest_transaction_event(&vcid)?;
let state = Serder::new_with_raw(event.as_bytes())?;
let dtnow = chrono::Utc::now();
let dte = chrono::DateTime::parse_from_rfc3339(&state.ked()["dt"].to_string()?)?.with_timezone(&chrono::Utc);
if (dtnow - dte).num_seconds() > Self::DEFAULT_CREDENTIAL_EXPIRY_SECONDS {
return err!(Error::Validation);
}
// added brv here for safety even though unimplemented
if [Ilkage::rev, Ilkage::brv].contains(&state.ked()[Ids::t].to_string()?.as_str()) {
return err!(Error::Validation);
}
schema_cache().verify(&schema, std::str::from_utf8(&creder.raw())?)?;
let mut rooted = false;
for group in quadlets.value() {
match group {
CesrGroup::SadPathSigVariant { value } => {
for sad_path_sig in value.value() {
if sad_path_sig.pather.bext()? != "-" {
continue;
}
rooted = true;
let event = self.store.get_key_event(&sad_path_sig.prefixer.qb64()?, sad_path_sig.seqner.sn()? as u32)?;
let serder = Serder::new_with_raw(event.as_bytes())?;
if serder.said()? != sad_path_sig.saider.qb64()? {
return err!(Error::Verification)
}
let verfers = serder.verfers()?;
let mut sigers = vec![];
for controller_idx_sig in sad_path_sig.sigers.value() {
let siger = &controller_idx_sig.siger;
if !sigers.contains(siger) {
sigers.push(siger.clone())
}
}
let mut verified_indices = vec![];
for siger in sigers {
if siger.index() as usize > verfers.len() {
return err!(Error::Verification);
}
if verfers[siger.index() as usize].verify(&siger.raw(), &creder.raw())? {
verified_indices.push(siger.index());
}
}
if let Some(tholder) = serder.tholder()? {
if !tholder.satisfy(&verified_indices)? {
return err!(Error::Verification);
}
} else {
return err!(Error::Verification);
}
}
},
_ => return err!(Error::Decoding)
}
}
if !rooted {
return err!(Error::Verification);
}
let edges = if prov.to_map().is_ok() {
vec![prov]
} else if prov.to_vec().is_ok() {
prov.to_vec()?
} else {
return err!(Error::Verification);
};
for edge in &edges {
for (label, node) in edge.to_map()? {
if [Ids::d, "o"].contains(&label.as_str()) {
continue;
}
let node_said = &node["n"].to_string()?;
let message = self.store.get_acdc(&node_said)?;
// here we need to default to true
if deep.unwrap_or(true) {
let pacdc = Creder::new_with_raw(message.as_bytes())?;
let (_, message_list) = MessageList::from_stream_bytes(message[pacdc.raw().len()..].as_bytes())?;
let group = message_list.messages[0].cesr_group()?;
match group {
CesrGroup::AttachedMaterialQuadletsVariant { value } => {
self.verify_acdc(&pacdc, value, deep)?;
},
_ => return err!(Error::Decoding)
}
}
}
}
let result = self.store.get_acdc(&vcid);
let existing = result.is_ok();
if existing {
let message = result.unwrap();
let eacdc = Creder::new_with_raw(message.as_bytes())?;
// this seems very bad, it means something is in the database that shouldn't be there. how did it get there?
if vcid != eacdc.said()? {
return err!(Error::Programmer);
}
}
println!("succesfully verified acdc {vcid}");
Ok(existing)
}
fn verify_key_event(&self, serder: &Serder, quadlets: &AttachedMaterialQuadlets, deep: Option<bool>) -> Result<bool> {
let pre = serder.pre()?;
let ked = serder.ked();
// see if code is supported
let prefixer = Prefixer::new_with_qb64(&pre)?;
let sn = serder.sn()?;
let ilk = ked["t"].to_string()?;
let said = serder.said()?;
let mut existing = false;
let (verfers, tholder) = if serder.est()? {
let tholder = if let Some(tholder) = serder.tholder()? {
tholder
} else {
return err!(Error::Decoding);
};
(serder.verfers()?, tholder)
} else {
let (raw, _) = self.store.get_latest_establishment_event_as_of_sn(&pre, sn as u32 - 1)?;
let serder = Serder::new_with_raw(raw.as_bytes())?;
let tholder = if let Some(tholder) = serder.tholder()? {
tholder
} else {
return err!(Error::Decoding);
};
(serder.verfers()?, tholder)
};
let mut verified_indices = vec![0u32; 0];
for group in quadlets.value() {
match group {
CesrGroup::ControllerIdxSigsVariant { value } => {
for controller_idx_sig in value.value() {
let siger = &controller_idx_sig.siger;
if siger.index() as usize > verfers.len() {
return err!(Error::Verification);
}
if verfers[siger.index() as usize].verify(&siger.raw(), &serder.raw())? {
verified_indices.push(siger.index());
}
}
}
_ => return err!(Error::Decoding)
}
}
if !tholder.satisfy(&verified_indices)? {
return err!(Error::Verification);
}
let labels = match ilk.as_str() {
Ilkage::icp => &Self::ICP_LABELS,
Ilkage::rot => &Self::ROT_LABELS,
Ilkage::ixn => &Self::IXN_LABELS,
_ => return err!(Error::Decoding),
};
if !Self::verify_ked_labels(&ked, labels)? {
return err!(Error::Validation);
}
let inceptive = &ilk == Ilkage::icp;
let key_event_count = self.store.count_key_events(&pre)?;
if inceptive {
if !prefixer.verify(&serder.ked(), Some(true))? {
return err!(Error::Verification);
}
if sn != 0 {
// must be 0
return err!(Error::Decoding);
}
if said != serder.pre()? {
return err!(Error::Verification);
}
if key_event_count != 0 {
existing = true;
}
} else {
if !serder.saider().verify(&serder.ked(), Some(inceptive), Some(true), None, None, None)? {
return err!(Error::Verification);
}
if sn < 1 {
return err!(Error::Validation);
}
let sno = key_event_count as u128;
if sn > sno {
// escrow here
return err!(Error::OutOfOrder);
}
if sn != sno {
existing = true;
}
// this sn implementation will become a problem at around 4 billion events
let event = self.store.get_key_event(&pre, sn as u32 - 1)?;
let pserder = Serder::new_with_raw(event.as_bytes())?;
if pserder.said()? != serder.ked()["p"].to_string()? {
return err!(Error::Verification);
}
if deep.unwrap_or(false) {
let (_, message_list) = MessageList::from_stream_bytes(event[pserder.raw().len()..].as_bytes())?;
let group = message_list.messages[0].cesr_group()?;
match group {
CesrGroup::AttachedMaterialQuadletsVariant { value } => {
self.verify_key_event(&pserder, value, deep)?;
},
_ => return err!(Error::Decoding)
}
}
}
if existing {
let event = self.store.get_key_event(&pre, sn as u32)?;
let eserder = Serder::new_with_raw(event.as_bytes())?;
// this seems very bad, it means something is in the database that shouldn't be there. how did it get there?
if said != eserder.said()? {
return err!(Error::Programmer);
}
}
println!("succesfully verified key event [{pre}, {said}]");
Ok(existing)
}
fn verify_transaction_event(&self, serder: &Serder, seal_source_couples: &SealSourceCouples, deep: Option<bool>) -> Result<bool> {
let pre = serder.pre()?;
let ked = serder.ked();
// see if code is supported
let prefixer = Prefixer::new_with_qb64(&pre)?;
let sn = serder.sn()?;
let ilk = ked["t"].to_string()?;
let said = serder.said()?;
let ri = Self::extract_registry_from_serder(&ilk, &serder)?;
let mut existing = false;
if seal_source_couples.value.len() != 1 {
return err!(Error::Decoding);
}
let source_saider = &seal_source_couples.value()[0].saider;
let source_seqner = &seal_source_couples.value()[0].seqner;
let labels = match ilk.as_str() {
Ilkage::vcp => &Self::VCP_LABELS,
Ilkage::iss => &Self::ISS_LABELS,
Ilkage::rev => &Self::REV_LABELS,
_ => return err!(Error::Decoding),
};
if !Self::verify_ked_labels(&ked, labels)? {
return err!(Error::Validation);
}
let inceptive = &ilk == Ilkage::vcp || &ilk == Ilkage::iss;
let transaction_event_count = self.store.count_transaction_events(&pre)?;
let apre = match ilk.as_str() {
Ilkage::vcp => {
if !prefixer.verify(&ked, Some(true))? {
return err!(Error::Verification);
}
ked["ii"].to_string()?
},
Ilkage::iss | Ilkage::rev => {
if !serder.saider().verify(&ked, Some(false), Some(true), None, None, None)? {
return err!(Error::Verification);
}
let rievent = self.store.get_transaction_event(&ri, 0)?;
let riserder = Serder::new_with_raw(rievent.as_bytes())?;
riserder.ked()["ii"].to_string()?
},
_ => return err!(Error::Decoding)
};
if !self.verify_anchor(&apre, source_seqner, source_saider, serder, deep)? {
return err!(Error::Verification);
}
if inceptive {
if sn != 0 {
// must be 0
return err!(Error::Decoding);
}
if transaction_event_count != 0 {
existing = true;
}
} else {
if sn < 1 {
return err!(Error::Validation);
}
let sno = transaction_event_count as u128;
if sn > sno {
// escrow here
return err!(Error::OutOfOrder);
}
if sn != sno {
existing = true;
}
// this sn implementation will become a problem at around 4 billion events
let event = self.store.get_transaction_event(&pre, sn as u32 - 1)?;
let pserder = Serder::new_with_raw(event.as_bytes())?;
if deep.unwrap_or(false) {
let (_, message_list) = MessageList::from_stream_bytes(event[pserder.raw().len()..].as_bytes())?;
let group = message_list.messages[0].cesr_group()?;
match group {
CesrGroup::SealSourceCouplesVariant { value } => {
self.verify_transaction_event(&pserder, value, deep)?;
},
_ => return err!(Error::Decoding)
}
}
if pserder.said()? != serder.ked()["p"].to_string()? {
return err!(Error::Verification);
}
}
if existing {
let event = self.store.get_transaction_event(&pre, sn as u32)?;
let eserder = Serder::new_with_raw(event.as_bytes())?;
// this seems very bad, it means something is in the database that shouldn't be there. how did it get there?
if said != eserder.said()? {
return err!(Error::Programmer);
}
}
println!("succesfully verified transaction event [{pre}, {said}]");
Ok(existing)
}
pub fn ingest_messages(&mut self, messages: &str, deep: Option<bool>) -> Result<()> {
let (_, message_list) = MessageList::from_stream_bytes(messages.as_bytes())?;
let mut messages = message_list.messages.iter();
loop {
let sadder = messages.next();
if let Some(sadder) = sadder {
let payload = sadder.payload()?;
let raw_string = payload.value.to_string();
let raw_message = raw_string.as_bytes();
let result = cesride::common::sniff(raw_message)?;
if result.ident == Identage::KERI {
let serder = Serder::new_with_raw(raw_message)?;
let message = messages.next();
if let Some(message) = message {
let group = message.cesr_group()?;
match serder.ked()["t"].to_string()?.as_str() {
Ilkage::icp | Ilkage::rot | Ilkage::ixn => {
match group {
CesrGroup::AttachedMaterialQuadletsVariant { value } => {
let existing = self.verify_key_event(&serder, value, deep)?;
if !existing {
let event = String::from_utf8(serder.raw())? + &group.qb64()?;
self.store.insert_key_event(&serder.pre()?, &event)?;
}
},
_ => return err!(Error::Decoding), // we only accept pipelined input at present
}
},
Ilkage::vcp | Ilkage::iss | Ilkage::rev => {
match group {
CesrGroup::SealSourceCouplesVariant { value } => {
let existing = self.verify_transaction_event(&serder, value, deep)?;
if !existing {
let event = String::from_utf8(serder.raw())? + &group.qb64()?;
self.store.insert_transaction_event(&serder.pre()?, &event)?;
}
},
_ => return err!(Error::Decoding),
}
}
_ => return err!(Error::Decoding),
}
} else {
return err!(Error::Decoding);
}
} else if result.ident == Identage::ACDC {
let creder = Creder::new_with_raw(raw_message)?;
let message = messages.next();
if let Some(message) = message {
let group = message.cesr_group()?;
match group {
CesrGroup::AttachedMaterialQuadletsVariant { value } => {
let existing = self.verify_acdc(&creder, value, deep)?;
if !existing {
let acdc = String::from_utf8(creder.raw())? + &group.qb64()?;
self.store.insert_acdc(&creder.said()?, &acdc)?;
}
},
_ => return err!(Error::Decoding), // we only accept pipelined input at present
};
} else {
return err!(Error::Decoding);
}
} else {
return err!(Error::Decoding)
}
} else {
break;
}
}
self.encrypt_and_cache_storage()
}Parside work currently resides alongside the cesride work.
- Zoom Link
- HackMD Link Bi-Weekly Meeting Agenda and Minutes
- Slack https://join.slack.com/t/keriworld/shared_invite/zt-14326yxue-p7P~GEmAZ65luGSZvbgFAQ
#cesrchannel.
- WebOfTrust/ietf-cesr repository - IETF draft specification for CESR
- Design Assumptions, Use Cases, and ToDo list - HackMD link
- Introductory articles: