refactor: extract RequestAuthenticator into auth package; use in smsapid and auth-proxy

Co-authored-by: coolaj86 <122831+coolaj86@users.noreply.github.com>

auth/request.go

@@ -0,0 +1,77 @@
+package auth
+
+import (
+	"errors"
+	"net/http"
+	"slices"
+	"strings"
+)
+
+// ErrNoCredentials is returned by RequestAuthenticator.Authenticate when the
+// request contains no recognizable form of credentials.
+var ErrNoCredentials = errors.New("no credentials provided")
+
+// RequestAuthenticator extracts credentials from an HTTP request and delegates
+// verification to a BasicAuthenticator. It supports Basic Auth, Authorization
+// header tokens, custom token headers, and query-parameter tokens.
+type RequestAuthenticator struct {
+	// AuthorizationSchemes lists accepted schemes for "Authorization: <scheme> <token>".
+	// nil accepts any scheme; a non-nil empty slice skips the Authorization header
+	// entirely; ["*"] also accepts any scheme; ["Bearer", "Token"] restricts to those.
+	AuthorizationSchemes []string
+
+	// TokenHeaders lists header names checked for bearer tokens,
+	// e.g. []string{"API-Key", "X-API-Key"}.
+	TokenHeaders []string
+
+	// TokenQueryParams lists query parameter names checked for tokens,
+	// e.g. []string{"access_token", "token"}.
+	TokenQueryParams []string
+}
+
+// Authenticate extracts credentials from r in this order:
+//  1. Basic Auth (Authorization: Basic …)
+//  2. Authorization: <scheme> <token> (filtered by AuthorizationSchemes)
+//  3. Token headers (TokenHeaders)
+//  4. Query parameters (TokenQueryParams)
+//
+// Returns ErrNoCredentials if no credential form is present in the request.
+func (ra *RequestAuthenticator) Authenticate(r *http.Request, a BasicAuthenticator) (BasicPrinciple, error) {
+	// 1. Basic Auth
+	if username, password, ok := r.BasicAuth(); ok {
+		return a.Authenticate(username, password)
+	}
+
+	// 2. Authorization: <scheme> <token>
+	// nil AuthorizationSchemes accepts any scheme; a non-nil empty slice skips.
+	if ra.AuthorizationSchemes == nil || len(ra.AuthorizationSchemes) > 0 {
+		if authHeader := r.Header.Get("Authorization"); authHeader != "" {
+			parts := strings.SplitN(authHeader, " ", 2)
+			if len(parts) == 2 {
+				scheme, token := parts[0], strings.TrimSpace(parts[1])
+				if ra.AuthorizationSchemes == nil ||
+					ra.AuthorizationSchemes[0] == "*" ||
+					slices.Contains(ra.AuthorizationSchemes, scheme) {
+					return a.Authenticate("", token)
+				}
+			}
+			return nil, ErrNoCredentials
+		}
+	}
+
+	// 3. Token headers
+	for _, h := range ra.TokenHeaders {
+		if token := r.Header.Get(h); token != "" {
+			return a.Authenticate("", token)
+		}
+	}
+
+	// 4. Query parameters
+	for _, p := range ra.TokenQueryParams {
+		if token := r.URL.Query().Get(p); token != "" {
+			return a.Authenticate("", token)
+		}
+	}
+
+	return nil, ErrNoCredentials
+}

cmd/auth-proxy/go.mod

@@ -4,10 +4,13 @@ go 1.25.0
 
 require (
 	github.com/joho/godotenv v1.5.1
+	github.com/therootcompany/golib/auth v1.0.0
 	github.com/therootcompany/golib/auth/csvauth v1.2.2
 )
 
-require (
-	github.com/therootcompany/golib/auth v1.0.0 // indirect
-	golang.org/x/crypto v0.42.0 // indirect
+require golang.org/x/crypto v0.42.0 // indirect
+
+replace (
+	github.com/therootcompany/golib/auth => ../../auth
+	github.com/therootcompany/golib/auth/csvauth => ../../auth/csvauth
 )

cmd/auth-proxy/main.go

@@ -593,47 +593,21 @@ func matchPattern(grant, rMethod, rHost, rPath string) bool {
 }
 
 func (cli *MainConfig) authenticate(r *http.Request) (auth.BasicPrinciple, error) {
-	// 1. Try Basic Auth first (cleanest path)
-	username, password, ok := r.BasicAuth()
-	if ok {
-		// Authorization: Basic <Auth> exists
-		return creds.Authenticate(username, password)
+	// nil AuthorizationHeaderSchemes means "not configured" → skip Authorization header.
+	schemes := cli.AuthorizationHeaderSchemes
+	if schemes == nil {
+		schemes = []string{} // non-nil empty slice → skip Authorization header
 	}
-
-	// 2. Any Authorization: <scheme> <token>
-	if len(cli.AuthorizationHeaderSchemes) > 0 {
-		authHeader := r.Header.Get("Authorization")
-		if authHeader != "" {
-			parts := strings.SplitN(authHeader, " ", 2)
-			if len(parts) == 2 {
-				if cli.AuthorizationHeaderSchemes[0] == "*" ||
-					slices.Contains(cli.AuthorizationHeaderSchemes, parts[0]) {
-					token := strings.TrimSpace(parts[1])
-					// Authorization: <Scheme> <Token> exists
-					return creds.Authenticate(basicAPIKeyName, token)
-				}
-			}
-			return nil, errors.New("'Authorization' header is not properly formatted")
-		}
+	ra := auth.RequestAuthenticator{
+		AuthorizationSchemes: schemes,
+		TokenHeaders:         cli.TokenHeaderNames,
+		TokenQueryParams:     cli.QueryParamNames,
 	}
-
-	// 3. API-Key / X-API-Key headers
-	for _, h := range cli.TokenHeaderNames {
-		if key := r.Header.Get(h); key != "" {
-			// <TokenHeader>: <Token> exists
-			return creds.Authenticate(basicAPIKeyName, key)
-		}
+	cred, err := ra.Authenticate(r, creds)
+	if errors.Is(err, auth.ErrNoCredentials) {
+		return nil, ErrNoAuth
 	}
-
-	// 4. access_token query param
-	for _, h := range cli.QueryParamNames {
-		if token := r.URL.Query().Get(h); token != "" {
-			// <query_param>?=<Token> exists
-			return creds.Authenticate(basicAPIKeyName, token)
-		}
-	}
-
-	return nil, ErrNoAuth
+	return cred, err
 }
 
 // peekOption looks for a flag value without parsing the full set

cmd/smsapid/go.mod

@@ -22,6 +22,7 @@ require (
 )
 
 replace (
+	github.com/therootcompany/golib/auth => ../../auth
 	github.com/therootcompany/golib/auth/csvauth => ../../auth/csvauth
 	github.com/therootcompany/golib/http/androidsmsgateway => ../../http/androidsmsgateway
 	github.com/therootcompany/golib/http/middleware/v2 => ../../http/middleware

cmd/smsapid/main.go

@@ -35,6 +35,10 @@ var pingWriter jsonl.Writer
 
 var smsAuth *csvauth.Auth
 
+var smsRequestAuth = &auth.RequestAuthenticator{
+	TokenHeaders: []string{"API-Key", "X-API-Key"},
+}
+
 func main() {
 	jsonf.Indent = 3
 
@@ -142,7 +146,7 @@ func requireSMSPermission(permission string) func(http.Handler) http.Handler {
 				http.Error(w, "Unauthorized", http.StatusUnauthorized)
 				return
 			}
-			cred, err := authenticateSMS(r)
+			cred, err := smsRequestAuth.Authenticate(r, smsAuth)
 			if err != nil || !hasSMSPermission(cred.Permissions(), permission) {
 				w.Header().Set("WWW-Authenticate", `Basic`)
 				http.Error(w, "Unauthorized", http.StatusUnauthorized)
@@ -153,32 +157,6 @@ func requireSMSPermission(permission string) func(http.Handler) http.Handler {
 	}
 }
 
-// authenticateSMS extracts and verifies credentials from Basic Auth, Authorization header, or API-Key header.
-func authenticateSMS(r *http.Request) (auth.BasicPrinciple, error) {
-	// 1. Basic Auth — Authenticate handles both login credentials and token-as-username/password.
-	if username, password, ok := r.BasicAuth(); ok {
-		return smsAuth.Authenticate(username, password)
-	}
-
-	// 2. Authorization: <scheme> <token>
-	if authHeader := r.Header.Get("Authorization"); authHeader != "" {
-		parts := strings.SplitN(authHeader, " ", 2)
-		if len(parts) == 2 {
-			return smsAuth.Authenticate("", strings.TrimSpace(parts[1]))
-		}
-		return nil, csvauth.ErrUnauthorized
-	}
-
-	// 3. API-Key / X-API-Key headers
-	for _, h := range []string{"API-Key", "X-API-Key"} {
-		if key := r.Header.Get(h); key != "" {
-			return smsAuth.Authenticate("", key)
-		}
-	}
-
-	return nil, csvauth.ErrNotFound
-}
-
 // getAESKey reads an AES-128 key (32 hex chars) from an environment variable.
 // Returns a zero key if the variable is absent or invalid.
 func getAESKey(envname string) []byte {