Merge pull request #32 from go-pkgz/hashed-auth

Hashed auth

Author: umputun

.github/workflows/ci.yml

@@ -11,10 +11,10 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-      - name: set up go 1.21
+      - name: set up go 1.23
         uses: actions/setup-go@v3
         with:
-          go-version: "1.21"
+          go-version: "1.23"
         id: go
 
       - name: checkout
@@ -33,11 +33,11 @@ jobs:
       - name: golangci-lint
         uses: golangci/golangci-lint-action@v3
         with:
-          version: latest
+          version: v1.61
 
       - name: install goveralls
         run: |
-          GO111MODULE=off go get -u -v github.com/mattn/goveralls
+          go install github.com/mattn/goveralls@latest
 
       - name: submit coverage
         run: $(go env GOPATH)/bin/goveralls -service="github" -coverprofile=$GITHUB_WORKSPACE/profile.cov

.golangci.yml

@@ -1,11 +1,11 @@
+run:
+  timeout: 5m
+  tests: false
+
 linters-settings:
   govet:
     enable:
       - shadow
-  gocyclo:
-    min-complexity: 15
-  dupl:
-    threshold: 100
   goconst:
     min-len: 2
     min-occurrences: 2
@@ -20,37 +20,47 @@ linters-settings:
       - experimental
     disabled-checks:
       - wrapperFunc
+      - hugeParam
+      - rangeValCopy
+      - singleCaseSwitch
+      - ifElseChain
 
 linters:
   enable:
-    - staticcheck
-    - gosimple
     - revive
     - govet
     - unconvert
+    - staticcheck
     - unused
     - gosec
-    - gocyclo
     - dupl
     - misspell
     - unparam
     - typecheck
     - ineffassign
     - stylecheck
     - gochecknoinits
-    - exportloopref
+    - copyloopvar
     - gocritic
     - nakedret
+    - gosimple
     - prealloc
   fast: false
   disable-all: true
 
 issues:
+  exclude-dirs:
+    - vendor
   exclude-rules:
-    - text: 'Deferring unsafe method "Close" on type "io.ReadCloser"'
+    - text: "at least one file in a package should have a package comment"
       linters:
-        - gosec
+        - stylecheck
+    - text: "should have a package comment"
+      linters:
+        - revive
     - path: _test\.go
       linters:
+        - gosec
         - dupl
-  exclude-use-default: false
+  exclude-use-default: false
+

README.md

@@ -182,6 +182,58 @@ example with chi router:
 	router.Use(rest.Reject(http.StatusBadRequest, "X-Request-Id header is required", rejectFn))
 ```
 
+### BasicAuth middleware family
+
+The package provides several BasicAuth middleware implementations for different authentication needs:
+
+#### BasicAuth
+The base middleware that requires basic auth and matches user & passwd with a client-provided checker function.
+```go
+checkFn := func(user, passwd string) bool {
+    return user == "admin" && passwd == "secret"
+}
+router.Use(rest.BasicAuth(checkFn))
+```
+
+#### BasicAuthWithUserPasswd
+A simpler version comparing user & password with provided values directly.
+```go
+router.Use(rest.BasicAuthWithUserPasswd("admin", "secret"))
+```
+
+#### BasicAuthWithBcryptHash
+Matches username and bcrypt-hashed password. Useful when storing hashed passwords.
+```go
+hash, err := rest.GenerateBcryptHash("secret")
+if err != nil {
+    // handle error
+}
+router.Use(rest.BasicAuthWithBcryptHash("admin", hash))
+```
+
+#### BasicAuthWithArgon2Hash
+Similar to bcrypt version but uses Argon2id hash with a separate salt. Both hash and salt are base64 encoded.
+```go
+hash, salt, err := rest.GenerateArgon2Hash("secret")
+if err != nil {
+    // handle error
+}
+router.Use(rest.BasicAuthWithArgon2Hash("admin", hash, salt))
+```
+
+#### BasicAuthWithPrompt
+Similar to BasicAuthWithUserPasswd but adds browser's authentication prompt by setting the WWW-Authenticate header.
+```go
+router.Use(rest.BasicAuthWithPrompt("admin", "secret"))
+```
+
+All BasicAuth middlewares:
+- Return `StatusUnauthorized` (401) if no auth header provided
+- Return `StatusForbidden` (403) if credentials check failed
+- Add IsAuthorized flag to the request context, retrievable with `rest.IsAuthorized(r.Context())`
+- Use constant-time comparison to prevent timing attacks
+- Support secure password hashing with bcrypt and Argon2id
+
 ### Benchmarks middleware
 
 Benchmarks middleware allows measuring the time of request handling, number of requests per second and report aggregated metrics. 

basic_auth.go

@@ -2,8 +2,13 @@ package rest
 
 import (
 	"context"
+	"crypto/rand"
 	"crypto/subtle"
+	"encoding/base64"
 	"net/http"
+
+	"golang.org/x/crypto/argon2"
+	"golang.org/x/crypto/bcrypt"
 )
 
 const baContextKey = "authorizedWithBasicAuth"
@@ -39,6 +44,42 @@ func BasicAuthWithUserPasswd(user, passwd string) func(http.Handler) http.Handle
 	return BasicAuth(checkFn)
 }
 
+// BasicAuthWithBcryptHash middleware requires basic auth and matches user & bcrypt hashed password
+func BasicAuthWithBcryptHash(user, hashedPassword string) func(http.Handler) http.Handler {
+	checkFn := func(reqUser, reqPasswd string) bool {
+		if reqUser != user {
+			return false
+		}
+		err := bcrypt.CompareHashAndPassword([]byte(hashedPassword), []byte(reqPasswd))
+		return err == nil
+	}
+	return BasicAuth(checkFn)
+}
+
+// BasicAuthWithArgon2Hash middleware requires basic auth and matches user & argon2 hashed password
+// both hashedPassword and salt must be base64 encoded strings
+// Uses Argon2id with parameters: t=1, m=64*1024 KB, p=4 threads
+func BasicAuthWithArgon2Hash(user, hashedPassword, salt string) func(http.Handler) http.Handler {
+	checkFn := func(reqUser, reqPasswd string) bool {
+		if reqUser != user {
+			return false
+		}
+
+		saltBytes, err := base64.StdEncoding.DecodeString(salt)
+		if err != nil {
+			return false
+		}
+		storedHashBytes, err := base64.StdEncoding.DecodeString(hashedPassword)
+		if err != nil {
+			return false
+		}
+
+		hash := argon2.IDKey([]byte(reqPasswd), saltBytes, 1, 64*1024, 4, 32)
+		return subtle.ConstantTimeCompare(hash, storedHashBytes) == 1
+	}
+	return BasicAuth(checkFn)
+}
+
 // IsAuthorized returns true is user authorized.
 // it can be used in handlers to check if BasicAuth middleware was applied
 func IsAuthorized(ctx context.Context) bool {
@@ -71,3 +112,25 @@ func BasicAuthWithPrompt(user, passwd string) func(http.Handler) http.Handler {
 		return http.HandlerFunc(fn)
 	}
 }
+
+// GenerateBcryptHash generates a bcrypt hash from a password
+func GenerateBcryptHash(password string) (string, error) {
+	hash, err := bcrypt.GenerateFromPassword([]byte(password), bcrypt.DefaultCost)
+	if err != nil {
+		return "", err
+	}
+	return string(hash), nil
+}
+
+// GenerateArgon2Hash generates an argon2 hash and salt from a password
+func GenerateArgon2Hash(password string) (hash, salt string, err error) {
+	saltBytes := make([]byte, 16)
+	if _, err := rand.Read(saltBytes); err != nil {
+		return "", "", err
+	}
+
+	// using recommended parameters: time=1, memory=64*1024, threads=4, keyLen=32
+	hashBytes := argon2.IDKey([]byte(password), saltBytes, 1, 64*1024, 4, 32)
+
+	return base64.StdEncoding.EncodeToString(hashBytes), base64.StdEncoding.EncodeToString(saltBytes), nil
+}