Files
strfry/src/events.cpp
2023-03-06 09:12:12 -05:00

336 lines
12 KiB
C++

#include <openssl/sha.h>
#include "events.h"
std::string nostrJsonToFlat(const tao::json::value &v) {
flatbuffers::FlatBufferBuilder builder; // FIXME: pre-allocate size approximately the same as orig JSON?
// Extract values from JSON, add strings to builder
auto id = from_hex(v.at("id").get_string(), false);
auto pubkey = from_hex(v.at("pubkey").get_string(), false);
uint64_t created_at = v.at("created_at").get_unsigned();
uint64_t kind = v.at("kind").get_unsigned();
if (id.size() != 32) throw herr("unexpected id size");
if (pubkey.size() != 32) throw herr("unexpected pubkey size");
std::vector<flatbuffers::Offset<NostrIndex::TagGeneral>> tagsGeneral;
std::vector<flatbuffers::Offset<NostrIndex::TagFixed32>> tagsFixed32;
uint64_t expiration = 0;
if (v.at("tags").get_array().size() > cfg().events__maxNumTags) throw herr("too many tags: ", v.at("tags").get_array().size());
for (auto &tagArr : v.at("tags").get_array()) {
auto &tag = tagArr.get_array();
if (tag.size() < 1) throw herr("too few fields in tag");
auto tagName = tag.at(0).get_string();
auto tagVal = tag.size() >= 2 ? tag.at(1).get_string() : "";
if (tagName == "e" || tagName == "p") {
tagVal = from_hex(tagVal, false);
if (tagVal.size() != 32) throw herr("unexpected size for fixed-size tag");
tagsFixed32.emplace_back(NostrIndex::CreateTagFixed32(builder,
(uint8_t)tagName[0],
(NostrIndex::Fixed32Bytes*)tagVal.data()
));
} else if (tagName == "expiration") {
if (expiration == 0) {
expiration = parseUint64(tagVal);
if (expiration < 100) throw herr("invalid expiration");
}
} else if (tagName == "ephemeral") {
expiration = 1;
} else if (tagName.size() == 1) {
if (tagVal.size() > cfg().events__maxTagValSize) throw herr("tag val too large: ", tagVal.size());
if (tagVal.size() <= MAX_INDEXED_TAG_VAL_SIZE) {
tagsGeneral.emplace_back(NostrIndex::CreateTagGeneral(builder,
(uint8_t)tagName[0],
builder.CreateVector((uint8_t*)tagVal.data(), tagVal.size())
));
}
}
}
if (isDefaultReplaceableKind(kind)) {
tagsGeneral.emplace_back(NostrIndex::CreateTagGeneral(builder,
'd',
builder.CreateVector((uint8_t*)"", 0)
));
}
if (isDefaultEphemeralKind(kind)) {
expiration = 1;
}
// Create flatbuffer
auto eventPtr = NostrIndex::CreateEvent(builder,
(NostrIndex::Fixed32Bytes*)id.data(),
(NostrIndex::Fixed32Bytes*)pubkey.data(),
created_at,
kind,
builder.CreateVector<flatbuffers::Offset<NostrIndex::TagGeneral>>(tagsGeneral),
builder.CreateVector<flatbuffers::Offset<NostrIndex::TagFixed32>>(tagsFixed32),
expiration
);
builder.Finish(eventPtr);
return std::string(reinterpret_cast<char*>(builder.GetBufferPointer()), builder.GetSize());
}
std::string nostrHash(const tao::json::value &origJson) {
tao::json::value arr = tao::json::empty_array;
arr.emplace_back(0);
arr.emplace_back(origJson.at("pubkey"));
arr.emplace_back(origJson.at("created_at"));
arr.emplace_back(origJson.at("kind"));
arr.emplace_back(origJson.at("tags"));
arr.emplace_back(origJson.at("content"));
std::string encoded = tao::json::to_string(arr);
unsigned char hash[SHA256_DIGEST_LENGTH];
SHA256(reinterpret_cast<unsigned char*>(encoded.data()), encoded.size(), hash);
return std::string(reinterpret_cast<char*>(hash), SHA256_DIGEST_LENGTH);
}
bool verifySig(secp256k1_context* ctx, std::string_view sig, std::string_view hash, std::string_view pubkey) {
if (sig.size() != 64 || hash.size() != 32 || pubkey.size() != 32) throw herr("verify sig: bad input size");
secp256k1_xonly_pubkey pubkeyParsed;
if (!secp256k1_xonly_pubkey_parse(ctx, &pubkeyParsed, (const uint8_t*)pubkey.data())) throw herr("verify sig: bad pubkey");
return secp256k1_schnorrsig_verify(
ctx,
(const uint8_t*)sig.data(),
(const uint8_t*)hash.data(),
#ifdef SECP256K1_SCHNORRSIG_EXTRAPARAMS_INIT // old versions of libsecp256k1 didn't take a msg size param, this define added just after
hash.size(),
#endif
&pubkeyParsed
);
}
void verifyNostrEvent(secp256k1_context *secpCtx, const NostrIndex::Event *flat, const tao::json::value &origJson) {
auto hash = nostrHash(origJson);
if (hash != sv(flat->id())) throw herr("bad event id");
bool valid = verifySig(secpCtx, from_hex(origJson.at("sig").get_string(), false), sv(flat->id()), sv(flat->pubkey()));
if (!valid) throw herr("bad signature");
}
void verifyNostrEventJsonSize(std::string_view jsonStr) {
if (jsonStr.size() > cfg().events__maxEventSize) throw herr("event too large: ", jsonStr.size());
}
void verifyEventTimestamp(const NostrIndex::Event *flat) {
auto now = hoytech::curr_time_s();
auto ts = flat->created_at();
uint64_t earliest = now - (flat->expiration() == 1 ? cfg().events__rejectEphemeralEventsOlderThanSeconds : cfg().events__rejectEventsOlderThanSeconds);
uint64_t latest = now + cfg().events__rejectEventsNewerThanSeconds;
if (ts < earliest) throw herr("created_at too early");
if (ts > latest || ts > MAX_TIMESTAMP) throw herr("created_at too late");
if (flat->expiration() != 0 && flat->expiration() <= now) throw herr("event expired");
}
void parseAndVerifyEvent(const tao::json::value &origJson, secp256k1_context *secpCtx, bool verifyMsg, bool verifyTime, std::string &flatStr, std::string &jsonStr) {
flatStr = nostrJsonToFlat(origJson);
auto *flat = flatbuffers::GetRoot<NostrIndex::Event>(flatStr.data());
if (verifyTime) verifyEventTimestamp(flat);
if (verifyMsg) verifyNostrEvent(secpCtx, flat, origJson);
// Build new object to remove unknown top-level fields from json
jsonStr = tao::json::to_string(tao::json::value({
{ "content", &origJson.at("content") },
{ "created_at", &origJson.at("created_at") },
{ "id", &origJson.at("id") },
{ "kind", &origJson.at("kind") },
{ "pubkey", &origJson.at("pubkey") },
{ "sig", &origJson.at("sig") },
{ "tags", &origJson.at("tags") },
}));
if (verifyMsg) verifyNostrEventJsonSize(jsonStr);
}
std::optional<defaultDb::environment::View_Event> lookupEventById(lmdb::txn &txn, std::string_view id) {
std::optional<defaultDb::environment::View_Event> output;
env.generic_foreachFull(txn, env.dbi_Event__id, makeKey_StringUint64(id, 0), lmdb::to_sv<uint64_t>(0), [&](auto k, auto v) {
if (k.starts_with(id)) output = env.lookup_Event(txn, lmdb::from_sv<uint64_t>(v));
return false;
});
return output;
}
defaultDb::environment::View_Event lookupEventByLevId(lmdb::txn &txn, uint64_t levId) {
auto view = env.lookup_Event(txn, levId);
if (!view) throw herr("unable to lookup event by levId");
return *view;
}
uint64_t getMostRecentLevId(lmdb::txn &txn) {
uint64_t levId = 0;
env.foreach_Event(txn, [&](auto &ev){
levId = ev.primaryKeyId;
return false;
}, true);
return levId;
}
// Return result validity same as getEventJson(), see below
std::string_view decodeEventPayload(lmdb::txn &txn, Decompressor &decomp, std::string_view raw, uint32_t *outDictId, size_t *outCompressedSize) {
if (raw.size() == 0) throw herr("empty event in EventPayload");
if (raw[0] == '\x00') {
if (outDictId) *outDictId = 0;
return raw.substr(1);
} else if (raw[0] == '\x01') {
raw = raw.substr(1);
if (raw.size() < 4) throw herr("EventPayload record too short to read dictId");
uint32_t dictId = lmdb::from_sv<uint32_t>(raw.substr(0, 4));
raw = raw.substr(4);
decomp.reserve(cfg().events__maxEventSize);
std::string_view buf = decomp.decompress(txn, dictId, raw);
if (outDictId) *outDictId = dictId;
if (outCompressedSize) *outCompressedSize = raw.size();
return buf;
} else {
throw("Unexpected first byte in EventPayload");
}
}
// Return result only valid until one of: next call to getEventJson/decodeEventPayload, write to/closing of txn, or any action on decomp object
std::string_view getEventJson(lmdb::txn &txn, Decompressor &decomp, uint64_t levId) {
std::string_view eventPayload;
bool found = env.dbi_EventPayload.get(txn, lmdb::to_sv<uint64_t>(levId), eventPayload);
if (!found) throw herr("couldn't find event in EventPayload");
return getEventJson(txn, decomp, levId, eventPayload);
}
std::string_view getEventJson(lmdb::txn &txn, Decompressor &decomp, uint64_t levId, std::string_view eventPayload) {
return decodeEventPayload(txn, decomp, eventPayload, nullptr, nullptr);
}
void deleteEvent(lmdb::txn &txn, quadrable::Quadrable::UpdateSet &changes, defaultDb::environment::View_Event &ev) {
changes.del(flatEventToQuadrableKey(ev.flat_nested()));
env.dbi_EventPayload.del(txn, lmdb::to_sv<uint64_t>(ev.primaryKeyId));
env.delete_Event(txn, ev.primaryKeyId);
}
void writeEvents(lmdb::txn &txn, quadrable::Quadrable &qdb, std::vector<EventToWrite> &evs, uint64_t logLevel) {
std::sort(evs.begin(), evs.end(), [](auto &a, auto &b) { return a.quadKey < b.quadKey; });
auto changes = qdb.change();
std::string tmpBuf;
for (size_t i = 0; i < evs.size(); i++) {
auto &ev = evs[i];
const NostrIndex::Event *flat = flatbuffers::GetRoot<NostrIndex::Event>(ev.flatStr.data());
if (lookupEventById(txn, sv(flat->id())) || (i != 0 && ev.quadKey == evs[i-1].quadKey)) {
ev.status = EventWriteStatus::Duplicate;
continue;
}
if (env.lookup_Event__deletion(txn, std::string(sv(flat->id())) + std::string(sv(flat->pubkey())))) {
ev.status = EventWriteStatus::Deleted;
continue;
}
{
std::optional<std::string> replace;
for (const auto &tagPair : *(flat->tagsGeneral())) {
auto tagName = (char)tagPair->key();
if (tagName != 'd') continue;
replace = std::string(sv(tagPair->val()));
break;
}
if (replace) {
auto searchStr = std::string(sv(flat->pubkey())) + *replace;
auto searchKey = makeKey_StringUint64(searchStr, flat->kind());
env.generic_foreachFull(txn, env.dbi_Event__replace, searchKey, lmdb::to_sv<uint64_t>(MAX_U64), [&](auto k, auto v) {
ParsedKey_StringUint64 parsedKey(k);
if (parsedKey.s == searchStr && parsedKey.n == flat->kind()) {
auto otherEv = lookupEventByLevId(txn, lmdb::from_sv<uint64_t>(v));
if (otherEv.flat_nested()->created_at() < flat->created_at()) {
if (logLevel >= 1) LI << "Deleting event (d-tag). id=" << to_hex(sv(otherEv.flat_nested()->id()));
deleteEvent(txn, changes, otherEv);
} else {
ev.status = EventWriteStatus::Replaced;
}
}
return false;
}, true);
}
}
if (flat->kind() == 5) {
// Deletion event, delete all referenced events
for (const auto &tagPair : *(flat->tagsFixed32())) {
if (tagPair->key() == 'e') {
auto otherEv = lookupEventById(txn, sv(tagPair->val()));
if (otherEv && sv(otherEv->flat_nested()->pubkey()) == sv(flat->pubkey())) {
if (logLevel >= 1) LI << "Deleting event (kind 5). id=" << to_hex(sv(tagPair->val()));
deleteEvent(txn, changes, *otherEv);
}
}
}
}
if (ev.status == EventWriteStatus::Pending) {
ev.levId = env.insert_Event(txn, ev.receivedAt, ev.flatStr, (uint64_t)ev.sourceType, ev.sourceInfo);
tmpBuf.clear();
tmpBuf += '\x00';
tmpBuf += ev.jsonStr;
env.dbi_EventPayload.put(txn, lmdb::to_sv<uint64_t>(ev.levId), tmpBuf);
changes.put(ev.quadKey, "");
ev.status = EventWriteStatus::Written;
}
}
changes.apply(txn);
}