Factor out ServeProto::BasicClientConnection::handshake Hydra to share

This commit is contained in:
John Ericson 2022-02-20 19:24:07 +00:00
parent 4580bed3e4
commit 4a5ca576da
3 changed files with 43 additions and 9 deletions

View file

@ -64,15 +64,8 @@ ref<LegacySSHStore::Connection> LegacySSHStore::openConnection()
StringSink saved; StringSink saved;
TeeSource tee(conn->from, saved); TeeSource tee(conn->from, saved);
try { try {
conn->to << SERVE_MAGIC_1 << SERVE_PROTOCOL_VERSION; conn->remoteVersion = ServeProto::BasicClientConnection::handshake(
conn->to.flush(); conn->to, tee, SERVE_PROTOCOL_VERSION, host);
unsigned int magic = readInt(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);
} catch (SerialisationError & e) { } catch (SerialisationError & e) {
// in.close(): Don't let the remote block on us not writing. // in.close(): Don't let the remote block on us not writing.
conn->sshConn->in.close(); conn->sshConn->in.close();

View file

@ -4,6 +4,25 @@
namespace nix { namespace nix {
ServeProto::Version ServeProto::BasicClientConnection::handshake(
BufferedSink & to,
Source & from,
ServeProto::Version localVersion,
std::string_view host)
{
to << SERVE_MAGIC_1 << localVersion;
to.flush();
unsigned int magic = readInt(from);
if (magic != SERVE_MAGIC_2)
throw Error("'nix-store --serve' protocol mismatch from '%s'", host);
auto remoteVersion = readInt(from);
if (GET_PROTOCOL_MAJOR(remoteVersion) != 0x200)
throw Error("unsupported 'nix-store --serve' protocol version on '%s'", host);
return remoteVersion;
}
StorePathSet ServeProto::BasicClientConnection::queryValidPaths( StorePathSet ServeProto::BasicClientConnection::queryValidPaths(
const Store & store, const Store & store,
bool lock, const StorePathSet & paths, bool lock, const StorePathSet & paths,

View file

@ -63,6 +63,28 @@ struct ServeProto::BasicClientConnection
FdSource from; FdSource from;
ServeProto::Version remoteVersion; ServeProto::Version remoteVersion;
/**
* Establishes connection, negotiating version.
*
* @return the version provided by the other side of the
* connection.
*
* @param to Taken by reference to allow for various error handling
* mechanisms.
*
* @param from Taken by reference to allow for various error
* handling mechanisms.
*
* @param localVersion Our version which is sent over
*
* @param host Just used to add context to thrown exceptions.
*/
static ServeProto::Version handshake(
BufferedSink & to,
Source & from,
ServeProto::Version localVersion,
std::string_view host);
/** /**
* Coercion to `ServeProto::ReadConn`. This makes it easy to use the * Coercion to `ServeProto::ReadConn`. This makes it easy to use the
* factored out serve protocol serializers with a * factored out serve protocol serializers with a