libstore: despecialcase protocol version check

protocol versions are sent as u64. on the peer we read them as uint64,
check that the upper half is 0, and throw an exception if not. we then
read an arbitrary amount of data from the peer and dump it to the user
terminal. this is a little bit ridiculous, can never happen in correct
implementation, and is severly untested. let us just drop it entirely.

Change-Id: Ibd2f53a765341ed6439d40d9d1eac11e79c6b5e3
This commit is contained in:
eldritch horrors 2024-03-24 15:57:49 +01:00
parent 3e428f2289
commit c856b82c2e
2 changed files with 7 additions and 27 deletions

View file

@ -124,20 +124,9 @@ struct LegacySSHStore : public virtual LegacySSHStoreConfig, public virtual Stor
conn->to << SERVE_MAGIC_1 << SERVE_PROTOCOL_VERSION;
conn->to.flush();
StringSink saved;
try {
TeeSource tee(conn->from, saved);
unsigned int magic = readInt(tee);
if (magic != SERVE_MAGIC_2)
throw Error("'nix-store --serve' protocol mismatch from '%s'", host);
} catch (SerialisationError & e) {
/* In case the other side is waiting for our input,
close it. */
conn->sshConn->in.close();
auto msg = conn->from.drain();
throw Error("'nix-store --serve' protocol mismatch from '%s', got '%s'",
host, chomp(saved.s + msg));
}
uint64_t magic = readLongLong(conn->from);
if (magic != SERVE_MAGIC_2)
throw Error("'nix-store --serve' protocol mismatch from '%s'", host);
conn->remoteVersion = readInt(conn->from);
if (GET_PROTOCOL_MAJOR(conn->remoteVersion) != 0x200)
throw Error("unsupported 'nix-store --serve' protocol version on '%s'", host);

View file

@ -69,19 +69,10 @@ void RemoteStore::initConnection(Connection & conn)
conn.from.endOfFileError = "Nix daemon disconnected unexpectedly (maybe it crashed?)";
conn.to << WORKER_MAGIC_1;
conn.to.flush();
StringSink saved;
try {
TeeSource tee(conn.from, saved);
unsigned int magic = readInt(tee);
if (magic != WORKER_MAGIC_2)
throw Error("protocol mismatch");
} catch (SerialisationError & e) {
/* In case the other side is waiting for our input, close
it. */
conn.closeWrite();
auto msg = conn.from.drain();
throw Error("protocol mismatch, got '%s'", chomp(saved.s + msg));
}
uint64_t magic = readLongLong(conn.from);
if (magic != WORKER_MAGIC_2)
throw Error("protocol mismatch");
conn.from >> conn.daemonVersion;
if (GET_PROTOCOL_MAJOR(conn.daemonVersion) != GET_PROTOCOL_MAJOR(PROTOCOL_VERSION))