Skip to content

feat: add CoderVPN protocol definition & implementation #14855

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 1 commit into from
Oct 1, 2024
Merged

feat: add CoderVPN protocol definition & implementation #14855

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
8 changes: 8 additions & 0 deletions Makefile
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -488,6 +488,7 @@ gen: \
agent/proto/agent.pb.go \
provisionersdk/proto/provisioner.pb.go \
provisionerd/proto/provisionerd.pb.go \
vpn/vpn.proto \
coderd/database/dump.sql \
$(DB_GEN_FILES) \
site/src/api/typesGenerated.ts \
Expand Down Expand Up @@ -517,6 +518,7 @@ gen/mark-fresh:
agent/proto/agent.pb.go \
provisionersdk/proto/provisioner.pb.go \
provisionerd/proto/provisionerd.pb.go \
vpn/vpn.proto \
coderd/database/dump.sql \
$(DB_GEN_FILES) \
site/src/api/typesGenerated.ts \
Expand Down Expand Up @@ -600,6 +602,12 @@ provisionerd/proto/provisionerd.pb.go: provisionerd/proto/provisionerd.proto
--go-drpc_opt=paths=source_relative \
./provisionerd/proto/provisionerd.proto

vpn/vpn.pb.go: vpn/vpn.proto
protoc \
--go_out=. \
--go_opt=paths=source_relative \
./vpn/vpn.proto

site/src/api/typesGenerated.ts: $(wildcard scripts/apitypings/*) $(shell find ./codersdk $(FIND_EXCLUSIONS) -type f -name '*.go')
go run ./scripts/apitypings/ > $@
./scripts/pnpm_install.sh
Expand Down
135 changes: 135 additions & 0 deletions vpn/serdes.go
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,135 @@
package vpn

import (
"context"
"encoding/binary"
"io"
"sync"

"google.golang.org/protobuf/proto"

"cdr.dev/slog"
)

// MaxLength is the largest possible CoderVPN Protocol message size. This is set
// so that a misbehaving peer can't cause us to allocate a huge amount of memory.
const MaxLength = 0x1000000 // 16MiB

// serdes SERializes and DESerializes protobuf messages to and from the conn.
type serdes[S rpcMessage, R receivableRPCMessage[RR], RR any] struct {
ctx context.Context
logger slog.Logger
conn io.ReadWriteCloser
sendCh <-chan S
recvCh chan<- R
closeOnce sync.Once
wg sync.WaitGroup
}

func (s *serdes[_, R, RR]) recvLoop() {
s.logger.Debug(s.ctx, "starting recvLoop")
defer s.closeIdempotent()
defer close(s.recvCh)
for {
var length uint32
if err := binary.Read(s.conn, binary.BigEndian, &length); err != nil {
s.logger.Debug(s.ctx, "failed to read length", slog.Error(err))
return
}
if length > MaxLength {
s.logger.Critical(s.ctx, "message length exceeds max",
slog.F("length", length))
return
}
s.logger.Debug(s.ctx, "about to read message", slog.F("length", length))
mb := make([]byte, length)
if n, err := io.ReadFull(s.conn, mb); err != nil {
s.logger.Debug(s.ctx, "failed to read message",
slog.Error(err),
slog.F("num_bytes_read", n))
return
}
msg := R(new(RR))
if err := proto.Unmarshal(mb, msg); err != nil {
s.logger.Critical(s.ctx, "failed to unmarshal message", slog.Error(err))
return
}
select {
case s.recvCh <- msg:
s.logger.Debug(s.ctx, "passed received message to speaker")
case <-s.ctx.Done():
s.logger.Debug(s.ctx, "recvLoop canceled", slog.Error(s.ctx.Err()))
Copy link
Collaborator

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Could probably omit the ctx.Err() here

Copy link
Contributor Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I'll admit it's almost always "context canceled" but sometimes it's "deadline exceeded" and that's interesting and occasionally useful in debugging, which is what Debug messages are supposed to be for.

}
}
}

func (s *serdes[S, _, _]) sendLoop() {
s.logger.Debug(s.ctx, "starting sendLoop")
defer s.closeIdempotent()
for {
select {
case <-s.ctx.Done():
s.logger.Debug(s.ctx, "sendLoop canceled", slog.Error(s.ctx.Err()))
return
case msg, ok := <-s.sendCh:
if !ok {
s.logger.Debug(s.ctx, "sendCh closed")
return
}
mb, err := proto.Marshal(msg)
if err != nil {
s.logger.Critical(s.ctx, "failed to marshal message", slog.Error(err))
return
}
if err := binary.Write(s.conn, binary.BigEndian, uint32(len(mb))); err != nil {
s.logger.Debug(s.ctx, "failed to write length", slog.Error(err))
return
}
if _, err := s.conn.Write(mb); err != nil {
s.logger.Debug(s.ctx, "failed to write message", slog.Error(err))
return
}
}
}
}

func (s *serdes[_, _, _]) closeIdempotent() {
s.closeOnce.Do(func() {
if err := s.conn.Close(); err != nil {
s.logger.Error(s.ctx, "failed to close connection", slog.Error(err))
} else {
s.logger.Info(s.ctx, "closed connection")
}
})
}

func (s *serdes[_, _, _]) Close() error {
s.closeIdempotent()
s.wg.Wait()
return nil
}

func (s *serdes[_, _, _]) start() {
s.wg.Add(2)
go func() {
defer s.wg.Done()
s.recvLoop()
}()
go func() {
defer s.wg.Done()
s.sendLoop()
}()
}

func newSerdes[S rpcMessage, R receivableRPCMessage[RR], RR any](
ctx context.Context, logger slog.Logger, conn io.ReadWriteCloser,
sendCh <-chan S, recvCh chan<- R,
) *serdes[S, R, RR] {
return &serdes[S, R, RR]{
ctx: ctx,
logger: logger.Named("serdes"),
conn: conn,
sendCh: sendCh,
recvCh: recvCh,
}
}
Loading
Loading