tapiron/coller
1
0
Fork 0
forked from jriou/coller
Code Pull requests Activity

feat: Return top-level errors to clients

Browse source 
In order to reduce security risk, the server now returns only functional error
messages to the clients and log low-level error messages.

Fixes #35.

Signed-off-by: Julien Riou <julien@riou.xyz>
This commit is contained in:
Julien Riou 2025-10-01 18:11:30 +02:00
commit 55de3afc71
Signed by: jriou
GPG key ID: 9A099EDA51316854
4 changed files with 170 additions and 115 deletions
Download patch file Download diff file Expand all files Collapse all files

3
src/cmd/collerd/README.md
View file

@ -102,8 +102,7 @@ Body (JSON):
### Errors
Errors return **500 Server Internal Error** with the **JSON** payload:
* **message** (string): context of the error
* **error** (string): error message
* **message** (string): message of the error
## Dependencies

71
src/server/handlers_api.go
View file

@ -12,6 +12,43 @@ import (
"git.riou.xyz/jriou/coller/internal"
)
type APIErrorResponse struct {
Message string `json:"message"`
}
func (e APIErrorResponse) ToJSON() string {
b, err := json.Marshal(e)
if err == nil {
return string(b)
}
return fmt.Sprintf("{\"message\":\"could not serialize response to JSON\", \"error\":\"%v\"}", err)
}
func apiError(level int, w http.ResponseWriter, logger *slog.Logger, msg string, err error) {
if err != nil {
err = fmt.Errorf("%s: %w", msg, err)
}
logger.Error(fmt.Sprintf("%v", err))
w.Header().Set("Content-Type", "application/json")
w.WriteHeader(level)
fmt.Fprint(w, APIErrorResponse{
Message: msg,
}.ToJSON())
}
func APIError(w http.ResponseWriter, logger *slog.Logger, msg string, err error) {
apiError(http.StatusInternalServerError, w, logger, msg, err)
}
func APIErrorNotFound(w http.ResponseWriter, logger *slog.Logger, msg string, err error) {
apiError(http.StatusNotFound, w, logger, msg, err)
}
func APIErrorBadRequest(w http.ResponseWriter, logger *slog.Logger, msg string, err error) {
apiError(http.StatusBadRequest, w, logger, msg, err)
}
func HealthHandler(w http.ResponseWriter, r *http.Request) {
fmt.Fprintf(w, "OK")
}
@ -41,36 +78,38 @@ type CreateNoteResponse struct {
func (h *CreateNoteHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
w.Header().Set("Content-Type", "application/json")
logger := h.logger.With("handler", "CreateNoteHandler")
bodyReader := http.MaxBytesReader(w, r.Body, h.maxUploadSize)
defer r.Body.Close()
var body CreateNotePayload
err := json.NewDecoder(bodyReader).Decode(&body)
if err != nil {
WriteError(w, "could not decode payload to create note", err)
APIError(w, logger, "could not decode payload", err)
return
}
if !h.allowNoEncryption && !body.Encrypted {
WriteError(w, "could not create note", fmt.Errorf("encryption is mandatory"))
APIError(w, logger, "encryption is mandatory", nil)
return
}
if !h.allowClientEncryptionKey && body.EncryptionKey != "" {
WriteError(w, "could not create note", fmt.Errorf("client encryption key is not allowed"))
APIError(w, logger, "client encryption key is not allowed", nil)
return
}
content, err := internal.Decode(body.Content)
if err != nil {
WriteError(w, "could not decode content", err)
APIError(w, logger, "could not decode content", err)
return
}
note, err := h.db.Create(content, body.Password, body.EncryptionKey, body.Encrypted, body.Expiration, body.DeleteAfterRead, body.Language)
if err != nil {
WriteError(w, "could not create note", err)
APIError(w, logger, "could not create note", err)
return
}
@ -90,14 +129,14 @@ func (h *GetNoteHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
note, err := h.db.Get(id)
logger := h.logger.With("handler", "CreateNoteHandler", "note_id", id)
if err != nil {
WriteError(w, "could not get note", err)
APIError(w, logger, "could not find note", err)
} else if note == nil {
w.WriteHeader(http.StatusNotFound)
h.logger.Error("note does not exists", slog.Any("note_id", id))
APIErrorNotFound(w, logger, "note does not exist", err)
} else if note.PasswordHash != nil {
w.WriteHeader(http.StatusBadRequest)
h.logger.Error("note is password protected", slog.Any("note_id", note.ID))
APIErrorBadRequest(w, logger, "note is password protected", err)
} else {
if note.Encrypted {
w.Header().Set("Content-Type", "application/octet-stream")
@ -124,20 +163,22 @@ func (h *GetProtectedNoteHandler) ServeHTTP(w http.ResponseWriter, r *http.Reque
vars := mux.Vars(r)
id := vars["id"]
logger := h.logger.With("handler", "GetProtectedNoteHandler", "note_id", id)
bodyReader := http.MaxBytesReader(w, r.Body, h.maxUploadSize)
defer r.Body.Close()
var body GetProtectedNotePayload
err := json.NewDecoder(bodyReader).Decode(&body)
if err != nil {
WriteError(w, "could not decode payload to read protected note", err)
APIError(w, logger, "could not decode payload", err)
return
}
note, err := h.db.Get(id)
if err != nil {
WriteError(w, "could not get note", err)
APIError(w, logger, "could not find note", err)
return
} else if note == nil {
w.WriteHeader(http.StatusNotFound)
@ -147,15 +188,15 @@ func (h *GetProtectedNoteHandler) ServeHTTP(w http.ResponseWriter, r *http.Reque
if body.EncryptionKey != "" && note.Encrypted {
note.Content, err = internal.Decrypt(note.Content, body.EncryptionKey)
if err != nil {
WriteError(w, "could not decrypt note", err)
APIError(w, logger, "could not decrypt note", err)
return
}
}
if body.Password != "" && (note.PasswordHash != nil || len(note.PasswordHash) > 0) {
if body.Password == "" && (note.PasswordHash != nil || len(note.PasswordHash) > 0) {
err := bcrypt.CompareHashAndPassword(note.PasswordHash, []byte(body.Password))
if err != nil {
WriteError(w, "could not validate password", err)
APIError(w, logger, "could not validate password", err)
return
}
}

188
src/server/handlers_web.go
View file

@ -36,6 +36,20 @@ type PageData struct {
DisableEditor bool
}
func TemplateError(w http.ResponseWriter, pageData PageData, templates *template.Template, templateName string, logger *slog.Logger, msg string, err error) {
// Only show the top-level error to users
pageData.Err = fmt.Errorf("%s", msg)
// Show full error in the logs
if err != nil {
err = fmt.Errorf("%s: %w", msg, err)
} else {
err = pageData.Err
}
logger.Error(fmt.Sprintf("%v", err))
templates.ExecuteTemplate(w, templateName, pageData)
}
type HomeHandler struct {
Templates *template.Template
PageData PageData
@ -53,26 +67,33 @@ type CreateNoteWithFormHandler struct {
maxUploadSize int64
}
func (h *CreateNoteWithFormHandler) TemplateName() string {
return "create"
}
func (h *CreateNoteWithFormHandler) TemplateError(w http.ResponseWriter, logger *slog.Logger, msg string, err error) {
TemplateError(w, h.PageData, h.Templates, h.TemplateName(), logger, msg, err)
}
func (h *CreateNoteWithFormHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
h.PageData.Err = nil
templateName := "create"
h.logger.Debug("parsing multipart form")
logger := h.logger.With("handler", "CreateNoteWithFormHandler")
logger.Debug("parsing multipart form")
err := r.ParseMultipartForm(h.maxUploadSize)
if err != nil {
h.PageData.Err = err
h.Templates.ExecuteTemplate(w, templateName, h.PageData)
h.TemplateError(w, logger, "could not parse form", err)
return
}
h.logger.Debug("parsing content")
logger.Debug("parsing content")
content := []byte(r.FormValue("content"))
h.logger.Debug("parsing file")
logger.Debug("parsing file")
file, handler, err := r.FormFile("file")
if err != nil && !errors.Is(err, http.ErrMissingFile) {
h.PageData.Err = err
h.Templates.ExecuteTemplate(w, templateName, h.PageData)
h.TemplateError(w, logger, "could not parse file", err)
return
}
@ -81,15 +102,13 @@ func (h *CreateNoteWithFormHandler) ServeHTTP(w http.ResponseWriter, r *http.Req
h.logger.Debug("checking file size")
if handler.Size > h.maxUploadSize {
h.PageData.Err = fmt.Errorf("file too large (%d > %d)", handler.Size, h.maxUploadSize)
h.Templates.ExecuteTemplate(w, templateName, h.PageData)
h.TemplateError(w, logger, "file too large", err)
return
}
h.logger.Debug("checking file content type")
if !strings.HasPrefix(handler.Header.Get("Content-Type"), "text/") {
h.PageData.Err = fmt.Errorf("text file expected (got %s)", handler.Header.Get("Content-Type"))
h.Templates.ExecuteTemplate(w, templateName, h.PageData)
h.TemplateError(w, logger, "text file expected", err)
return
}
@ -97,8 +116,7 @@ func (h *CreateNoteWithFormHandler) ServeHTTP(w http.ResponseWriter, r *http.Req
var fileContent bytes.Buffer
n, err := io.Copy(&fileContent, file)
if err != nil {
h.PageData.Err = err
h.Templates.ExecuteTemplate(w, templateName, h.PageData)
h.TemplateError(w, logger, "could not read file", err)
return
}
@ -110,8 +128,7 @@ func (h *CreateNoteWithFormHandler) ServeHTTP(w http.ResponseWriter, r *http.Req
h.logger.Debug("checking content")
if content == nil || len(content) == 0 {
h.PageData.Err = fmt.Errorf("empty note")
h.Templates.ExecuteTemplate(w, templateName, h.PageData)
h.TemplateError(w, logger, "empty note", nil)
return
}
@ -124,33 +141,34 @@ func (h *CreateNoteWithFormHandler) ServeHTTP(w http.ResponseWriter, r *http.Req
language := r.FormValue("language")
if !h.PageData.AllowNoEncryption && noEncryption != "" {
h.PageData.Err = fmt.Errorf("encryption is mandatory")
h.Templates.ExecuteTemplate(w, templateName, h.PageData)
h.TemplateError(w, logger, "encryption is required", nil)
}
if !h.PageData.AllowClientEncryptionKey && encryptionKey != "" {
h.PageData.Err = fmt.Errorf("client encryption key is not allowed")
h.Templates.ExecuteTemplate(w, templateName, h.PageData)
h.TemplateError(w, logger, "client encryption key is not allowed", nil)
}
if !h.PageData.AllowClientEncryptionKey && encryptionKey == "" && noEncryption == "" {
h.logger.Debug("generating encryption key")
logger.Debug("generating encryption key")
encryptionKey = internal.GenerateChars(encryptionKeyLength)
}
h.logger.Debug("computing expiration")
logger.Debug("computing expiration")
var expirationInt int
if expiration == "Expiration" {
expirationInt = 0
} else {
expirationInt, _ = strconv.Atoi(expiration)
expirationInt, err = strconv.Atoi(expiration)
if err != nil {
h.TemplateError(w, logger, "invalid expiration", err)
return
}
}
h.logger.Debug("saving note to the database")
logger.Debug("saving note to the database")
note, err := h.db.Create(content, password, encryptionKey, encryptionKey != "", expirationInt, deleteAfterRead != "", language)
if err != nil {
h.PageData.Err = err
h.Templates.ExecuteTemplate(w, templateName, h.PageData)
h.TemplateError(w, logger, "could not create note", err)
return
}
@ -166,7 +184,7 @@ func (h *CreateNoteWithFormHandler) ServeHTTP(w http.ResponseWriter, r *http.Req
}
h.logger.Debug("rendering page")
h.Templates.ExecuteTemplate(w, templateName, h.PageData)
h.Templates.ExecuteTemplate(w, h.TemplateName(), h.PageData)
}
type GetRawWebNoteHandler struct {
@ -176,36 +194,43 @@ type GetRawWebNoteHandler struct {
db *Database
}
func (h *GetRawWebNoteHandler) TemplateName() string {
return "unprotectedNote"
}
func (h *GetRawWebNoteHandler) TemplateError(w http.ResponseWriter, logger *slog.Logger, msg string, err error) {
TemplateError(w, h.PageData, h.Templates, h.TemplateName(), logger, msg, err)
}
func (h *GetRawWebNoteHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
h.PageData.Err = nil
templateName := "unprotectedNote"
vars := mux.Vars(r)
id := vars["id"]
logger := h.logger.With("handler", "GetRawWebNoteHandler", "note_id", id)
logger.Debug("fetching note from the database")
note, err := h.db.Get(id)
if err != nil {
h.PageData.Err = fmt.Errorf("could not get raw note")
h.Templates.ExecuteTemplate(w, templateName, h.PageData)
h.TemplateError(w, logger, "could not find note", err)
return
}
if note == nil {
h.PageData.Err = fmt.Errorf("note doesn't exist or has been deleted")
h.Templates.ExecuteTemplate(w, templateName, h.PageData)
h.TemplateError(w, logger, "note does not exist", err)
return
}
h.PageData.Note = note
h.logger.Debug("rendering page")
if note.Encrypted || len(note.PasswordHash) > 0 {
h.Templates.ExecuteTemplate(w, templateName, h.PageData)
logger.Debug("rendering page")
h.PageData.Note = note
h.Templates.ExecuteTemplate(w, h.TemplateName(), h.PageData)
return
}
logger.Debug("returning content")
w.Header().Set("Content-Type", "text/plain; charset=utf-8")
w.WriteHeader(http.StatusOK)
fmt.Fprint(w, string(note.Content))
@ -219,64 +244,67 @@ type GetProtectedRawWebNoteHandler struct {
maxUploadSize int64
}
func (h *GetProtectedRawWebNoteHandler) TemplateName() string {
return "protectedNote"
}
func (h *GetProtectedRawWebNoteHandler) TemplateError(w http.ResponseWriter, logger *slog.Logger, msg string, err error) {
TemplateError(w, h.PageData, h.Templates, h.TemplateName(), logger, msg, err)
}
func (h *GetProtectedRawWebNoteHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
h.PageData.Err = nil
templateName := "protectedNote"
vars := mux.Vars(r)
id := vars["id"]
h.logger.Debug("parsing multipart form")
logger := h.logger.With("handler", "GetProtectedRawWebNoteHandler", "note_id", id)
logger.Debug("parsing multipart form")
err := r.ParseMultipartForm(h.maxUploadSize)
if err != nil {
h.PageData.Err = err
h.Templates.ExecuteTemplate(w, templateName, h.PageData)
h.TemplateError(w, logger, "could not parse form", err)
return
}
password := r.FormValue("password")
encryptionKey := r.FormValue("encryption-key")
logger.Debug("fetching note from the database")
note, err := h.db.Get(id)
if err != nil {
h.PageData.Err = fmt.Errorf("could not find note")
h.Templates.ExecuteTemplate(w, templateName, h.PageData)
h.TemplateError(w, logger, "could not find note", err)
return
}
if note == nil {
h.PageData.Err = fmt.Errorf("note doesn't exist or has been deleted")
h.Templates.ExecuteTemplate(w, templateName, h.PageData)
h.TemplateError(w, logger, "note does not exist", nil)
return
}
if note.Encrypted {
if encryptionKey == "" {
h.PageData.Err = fmt.Errorf("encryption key not found")
h.Templates.ExecuteTemplate(w, templateName, h.PageData)
h.TemplateError(w, logger, "encryption key not found", nil)
return
}
logger.Debug("decrypting content")
note.Content, err = internal.Decrypt(note.Content, encryptionKey)
if err != nil {
h.PageData.Err = fmt.Errorf("could not decrypt note")
h.Templates.ExecuteTemplate(w, templateName, h.PageData)
h.TemplateError(w, logger, "could not decrypt note", err)
return
}
}
if len(note.PasswordHash) > 0 {
logger.Debug("comparing password hashes")
if err := bcrypt.CompareHashAndPassword(note.PasswordHash, []byte(password)); err != nil {
h.PageData.Err = fmt.Errorf("invalid password")
h.Templates.ExecuteTemplate(w, templateName, h.PageData)
h.TemplateError(w, logger, "invalid password", err)
return
}
}
h.PageData.Note = note
h.logger.Debug("rendering page")
logger.Debug("returning content")
w.Header().Set("Content-Type", "text/plain; charset=utf-8")
w.WriteHeader(http.StatusOK)
fmt.Fprint(w, string(note.Content))
@ -289,31 +317,38 @@ type GetWebNoteHandler struct {
db *Database
}
func (h *GetWebNoteHandler) TemplateName() string {
return "unprotectedNote"
}
func (h *GetWebNoteHandler) TemplateError(w http.ResponseWriter, logger *slog.Logger, msg string, err error) {
TemplateError(w, h.PageData, h.Templates, h.TemplateName(), logger, msg, err)
}
func (h *GetWebNoteHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
h.PageData.Err = nil
templateName := "unprotectedNote"
vars := mux.Vars(r)
id := vars["id"]
logger := h.logger.With("handler", "GetWebNoteHandler", "note_id", id)
note, err := h.db.Get(id)
if err != nil {
h.PageData.Err = err
h.Templates.ExecuteTemplate(w, templateName, h.PageData)
h.TemplateError(w, logger, "could not find note", err)
return
}
if note == nil {
h.PageData.Err = fmt.Errorf("note doesn't exist or has been deleted")
h.Templates.ExecuteTemplate(w, templateName, h.PageData)
h.TemplateError(w, logger, "note does not exist", nil)
return
}
h.PageData.Note = note
h.logger.Debug("rendering page")
h.Templates.ExecuteTemplate(w, templateName, h.PageData)
h.Templates.ExecuteTemplate(w, h.TemplateName(), h.PageData)
}
type GetProtectedWebNoteHandler struct {
@ -324,18 +359,26 @@ type GetProtectedWebNoteHandler struct {
maxUploadSize int64
}
func (h *GetProtectedWebNoteHandler) TemplateName() string {
return "protectedNote"
}
func (h *GetProtectedWebNoteHandler) TemplateError(w http.ResponseWriter, logger *slog.Logger, msg string, err error) {
TemplateError(w, h.PageData, h.Templates, h.TemplateName(), logger, msg, err)
}
func (h *GetProtectedWebNoteHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
h.PageData.Err = nil
templateName := "protectedNote"
vars := mux.Vars(r)
id := vars["id"]
logger := h.logger.With("handler", "GetProtectedWebNoteHandler", "note_id", id)
h.logger.Debug("parsing multipart form")
err := r.ParseMultipartForm(h.maxUploadSize)
if err != nil {
h.PageData.Err = err
h.Templates.ExecuteTemplate(w, templateName, h.PageData)
h.TemplateError(w, logger, "could not parse form", err)
return
}
@ -345,35 +388,30 @@ func (h *GetProtectedWebNoteHandler) ServeHTTP(w http.ResponseWriter, r *http.Re
note, err := h.db.Get(id)
if err != nil {
h.PageData.Err = fmt.Errorf("could not find note")
h.Templates.ExecuteTemplate(w, templateName, h.PageData)
h.TemplateError(w, logger, "could not find note", err)
return
}
if note == nil {
h.PageData.Err = fmt.Errorf("note doesn't exist or has been deleted")
h.Templates.ExecuteTemplate(w, templateName, h.PageData)
h.TemplateError(w, logger, "note does not exist", nil)
return
}
if note.Encrypted {
if encryptionKey == "" {
h.PageData.Err = fmt.Errorf("encryption key not found")
h.Templates.ExecuteTemplate(w, templateName, h.PageData)
h.TemplateError(w, logger, "encryption key not found", nil)
return
}
note.Content, err = internal.Decrypt(note.Content, encryptionKey)
if err != nil {
h.PageData.Err = fmt.Errorf("could not decrypt note")
h.Templates.ExecuteTemplate(w, templateName, h.PageData)
h.TemplateError(w, logger, "could not decrypt note", err)
return
}
}
if len(note.PasswordHash) > 0 {
if err := bcrypt.CompareHashAndPassword(note.PasswordHash, []byte(password)); err != nil {
h.PageData.Err = fmt.Errorf("invalid password")
h.Templates.ExecuteTemplate(w, templateName, h.PageData)
h.TemplateError(w, logger, "invalid password", err)
return
}
}
@ -381,7 +419,7 @@ func (h *GetProtectedWebNoteHandler) ServeHTTP(w http.ResponseWriter, r *http.Re
h.PageData.Note = note
h.logger.Debug("rendering page")
h.Templates.ExecuteTemplate(w, templateName, h.PageData)
h.Templates.ExecuteTemplate(w, h.TemplateName(), h.PageData)
}
type ClientsHandler struct {

23
src/server/server.go
View file

@ -2,7 +2,6 @@ package server
import (
"embed"
"encoding/json"
"fmt"
"html/template"
"log/slog"
@ -49,28 +48,6 @@ func (s *Server) SetMetrics(metrics *Metrics) {
s.metrics = metrics
}
type ErrorResponse struct {
Message string `json:"message"`
Error string `json:"error"`
}
func (e ErrorResponse) ToJSON() string {
b, err := json.Marshal(e)
if err == nil {
return string(b)
}
return fmt.Sprintf("{\"message\":\"could not serialize response to JSON\", \"error\":\"%v\"}", err)
}
func WriteError(w http.ResponseWriter, message string, err error) {
w.Header().Set("Content-Type", "application/json")
w.WriteHeader(http.StatusInternalServerError)
fmt.Fprint(w, ErrorResponse{
Message: message,
Error: fmt.Sprintf("%v", err),
}.ToJSON())
}
//go:embed templates/*.html
var templatesFS embed.FS