fix: get envoy host from the gin request

Bumps the minor-patch group in /frontend with 2 updates: [i18next](https://github.com/i18next/i18next) and [react-i18next](https://github.com/i18next/react-i18next).


Updates `i18next` from 25.8.17 to 25.8.18
- [Release notes](https://github.com/i18next/i18next/releases)
- [Changelog](https://github.com/i18next/i18next/blob/master/CHANGELOG.md)
- [Commits](https://github.com/i18next/i18next/compare/v25.8.17...v25.8.18)

Updates `react-i18next` from 16.5.6 to 16.5.8
- [Changelog](https://github.com/i18next/react-i18next/blob/master/CHANGELOG.md)
- [Commits](https://github.com/i18next/react-i18next/compare/v16.5.6...v16.5.8)

---
updated-dependencies:
- dependency-name: i18next
  dependency-version: 25.8.18
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: minor-patch
- dependency-name: react-i18next
  dependency-version: 16.5.8
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: minor-patch
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

frontend/bun.lock

@@ -16,7 +16,7 @@
         "axios": "^1.13.6",
         "class-variance-authority": "^0.7.1",
         "clsx": "^2.1.1",
-        "i18next": "^25.8.17",
+        "i18next": "^25.8.18",
         "i18next-browser-languagedetector": "^8.2.1",
         "i18next-resources-to-backend": "^1.2.1",
         "input-otp": "^1.4.2",
@@ -26,7 +26,7 @@
         "react": "^19.2.4",
         "react-dom": "^19.2.4",
         "react-hook-form": "^7.71.2",
-        "react-i18next": "^16.5.6",
+        "react-i18next": "^16.5.8",
         "react-markdown": "^10.1.0",
         "react-router": "^7.13.1",
         "sonner": "^2.0.7",
@@ -637,7 +637,7 @@
 
     "html-url-attributes": ["html-url-attributes@3.0.1", "", {}, "sha512-ol6UPyBWqsrO6EJySPz2O7ZSr856WDrEzM5zMqp+FJJLGMW35cLYmmZnl0vztAZxRUoNZJFTCohfjuIJ8I4QBQ=="],
 
-    "i18next": ["i18next@25.8.17", "", { "dependencies": { "@babel/runtime": "^7.28.6" }, "peerDependencies": { "typescript": "^5" }, "optionalPeers": ["typescript"] }, "sha512-vWtCttyn5bpOK4hWbRAe1ZXkA+Yzcn2OcACT+WJavtfGMcxzkfvXTLMeOU8MUhRmAySKjU4VVuKlo0sSGeBokA=="],
+    "i18next": ["i18next@25.8.18", "", { "dependencies": { "@babel/runtime": "^7.28.6" }, "peerDependencies": { "typescript": "^5" }, "optionalPeers": ["typescript"] }, "sha512-lzY5X83BiL5AP77+9DydbrqkQHFN9hUzWGjqjLpPcp5ZOzuu1aSoKaU3xbBLSjWx9dAzW431y+d+aogxOZaKRA=="],
 
     "i18next-browser-languagedetector": ["i18next-browser-languagedetector@8.2.1", "", { "dependencies": { "@babel/runtime": "^7.23.2" } }, "sha512-bZg8+4bdmaOiApD7N7BPT9W8MLZG+nPTOFlLiJiT8uzKXFjhxw4v2ierCXOwB5sFDMtuA5G4kgYZ0AznZxQ/cw=="],
 
@@ -843,7 +843,7 @@
 
     "react-hook-form": ["react-hook-form@7.71.2", "", { "peerDependencies": { "react": "^16.8.0 || ^17 || ^18 || ^19" } }, "sha512-1CHvcDYzuRUNOflt4MOq3ZM46AronNJtQ1S7tnX6YN4y72qhgiUItpacZUAQ0TyWYci3yz1X+rXaSxiuEm86PA=="],
 
-    "react-i18next": ["react-i18next@16.5.6", "", { "dependencies": { "@babel/runtime": "^7.28.4", "html-parse-stringify": "^3.0.1", "use-sync-external-store": "^1.6.0" }, "peerDependencies": { "i18next": ">= 25.6.2", "react": ">= 16.8.0", "typescript": "^5" }, "optionalPeers": ["typescript"] }, "sha512-Ua7V2/efA88ido7KyK51fb8Ki8M/sRfW8LR/rZ/9ZKr2luhuTI7kwYZN5agT1rWG7aYm5G0RYE/6JR8KJoCMDw=="],
+    "react-i18next": ["react-i18next@16.5.8", "", { "dependencies": { "@babel/runtime": "^7.28.4", "html-parse-stringify": "^3.0.1", "use-sync-external-store": "^1.6.0" }, "peerDependencies": { "i18next": ">= 25.6.2", "react": ">= 16.8.0", "typescript": "^5" }, "optionalPeers": ["typescript"] }, "sha512-2ABeHHlakxVY+LSirD+OiERxFL6+zip0PaHo979bgwzeHg27Sqc82xxXWIrSFmfWX0ZkrvXMHwhsi/NGUf5VQg=="],
 
     "react-markdown": ["react-markdown@10.1.0", "", { "dependencies": { "@types/hast": "^3.0.0", "@types/mdast": "^4.0.0", "devlop": "^1.0.0", "hast-util-to-jsx-runtime": "^2.0.0", "html-url-attributes": "^3.0.0", "mdast-util-to-hast": "^13.0.0", "remark-parse": "^11.0.0", "remark-rehype": "^11.0.0", "unified": "^11.0.0", "unist-util-visit": "^5.0.0", "vfile": "^6.0.0" }, "peerDependencies": { "@types/react": ">=18", "react": ">=18" } }, "sha512-qKxVopLT/TyA6BX3Ue5NwabOsAzm0Q7kAPwq6L+wWDwisYs7R8vZ0nRXqq6rkueboxpkjvLGU9fWifiX/ZZFxQ=="],
 

frontend/package.json

@@ -22,7 +22,7 @@
     "axios": "^1.13.6",
     "class-variance-authority": "^0.7.1",
     "clsx": "^2.1.1",
-    "i18next": "^25.8.17",
+    "i18next": "^25.8.18",
     "i18next-browser-languagedetector": "^8.2.1",
     "i18next-resources-to-backend": "^1.2.1",
     "input-otp": "^1.4.2",
@@ -32,7 +32,7 @@
     "react": "^19.2.4",
     "react-dom": "^19.2.4",
     "react-hook-form": "^7.71.2",
-    "react-i18next": "^16.5.6",
+    "react-i18next": "^16.5.8",
     "react-markdown": "^10.1.0",
     "react-router": "^7.13.1",
     "sonner": "^2.0.7",

go.mod

@@ -19,7 +19,7 @@ require (
 	github.com/rs/zerolog v1.34.0
 	github.com/traefik/paerser v0.2.2
 	github.com/weppos/publicsuffix-go v0.50.3
-	golang.org/x/crypto v0.48.0
+	golang.org/x/crypto v0.49.0
 	golang.org/x/exp v0.0.0-20251023183803-a4bb9ffd2546
 	golang.org/x/oauth2 v0.36.0
 	gotest.tools/v3 v3.5.2
@@ -114,10 +114,10 @@ require (
 	go.opentelemetry.io/otel/trace v1.37.0 // indirect
 	golang.org/x/arch v0.22.0 // indirect
 	golang.org/x/net v0.51.0 // indirect
-	golang.org/x/sync v0.19.0 // indirect
+	golang.org/x/sync v0.20.0 // indirect
-	golang.org/x/sys v0.41.0 // indirect
+	golang.org/x/sys v0.42.0 // indirect
-	golang.org/x/term v0.40.0 // indirect
+	golang.org/x/term v0.41.0 // indirect
-	golang.org/x/text v0.34.0 // indirect
+	golang.org/x/text v0.35.0 // indirect
 	google.golang.org/protobuf v1.36.10 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 	modernc.org/libc v1.67.6 // indirect

go.sum

@@ -309,13 +309,13 @@ golang.org/x/arch v0.22.0/go.mod h1:dNHoOeKiyja7GTvF9NJS1l3Z2yntpQNzgrjh1cU103A=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20210921155107-089bfa567519/go.mod h1:GvvjBRRGRdwPK5ydBHafDWAxML/pGHZbMvKqRZ5+Abc=
 golang.org/x/crypto v0.3.0/go.mod h1:hebNnKkNXi2UzZN1eVRvBB7co0a+JxK6XbPiWVs/3J4=
-golang.org/x/crypto v0.48.0 h1:/VRzVqiRSggnhY7gNRxPauEQ5Drw9haKdM0jqfcCFts=
+golang.org/x/crypto v0.49.0 h1:+Ng2ULVvLHnJ/ZFEq4KdcDd/cfjrrjjNSXNzxg0Y4U4=
-golang.org/x/crypto v0.48.0/go.mod h1:r0kV5h3qnFPlQnBSrULhlsRfryS2pmewsg+XfMgkVos=
+golang.org/x/crypto v0.49.0/go.mod h1:ErX4dUh2UM+CFYiXZRTcMpEcN8b/1gxEuv3nODoYtCA=
 golang.org/x/exp v0.0.0-20251023183803-a4bb9ffd2546 h1:mgKeJMpvi0yx/sU5GsxQ7p6s2wtOnGAHZWCHUM4KGzY=
 golang.org/x/exp v0.0.0-20251023183803-a4bb9ffd2546/go.mod h1:j/pmGrbnkbPtQfxEe5D0VQhZC6qKbfKifgD0oM7sR70=
 golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4/go.mod h1:jJ57K6gSWd91VN4djpZkiMVwK6gcyfeH4XE8wZrZaV4=
-golang.org/x/mod v0.32.0 h1:9F4d3PHLljb6x//jOyokMv3eX+YDeepZSEo3mFJy93c=
+golang.org/x/mod v0.33.0 h1:tHFzIWbBifEmbwtGz65eaWyGiGZatSrT9prnU8DbVL8=
-golang.org/x/mod v0.32.0/go.mod h1:SgipZ/3h2Ci89DlEtEXWUk/HteuRin+HHhN+WbNhguU=
+golang.org/x/mod v0.33.0/go.mod h1:swjeQEj+6r7fODbD2cqrnje9PnziFuw4bmLbBZFrQ5w=
 golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/net v0.0.0-20210226172049-e18ecbb05110/go.mod h1:m0MpNAwzfU5UDzcl9v0D8zg8gWTRqZa9RBIspLL5mdg=
 golang.org/x/net v0.0.0-20220722155237-a158d28d115b/go.mod h1:XRhObCWvk6IyKnWLug+ECip1KBveYUHfp+8e9klMJ9c=
@@ -326,8 +326,8 @@ golang.org/x/oauth2 v0.36.0 h1:peZ/1z27fi9hUOFCAZaHyrpWG5lwe0RJEEEeH0ThlIs=
 golang.org/x/oauth2 v0.36.0/go.mod h1:YDBUJMTkDnJS+A4BP4eZBjCqtokkg1hODuPjwiGPO7Q=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20220722155255-886fb9371eb4/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
-golang.org/x/sync v0.19.0 h1:vV+1eWNmZ5geRlYjzm2adRgW2/mcpevXNg50YZtPCE4=
+golang.org/x/sync v0.20.0 h1:e0PTpb7pjO8GAtTs2dQ6jYa5BWYlMuX047Dco/pItO4=
-golang.org/x/sync v0.19.0/go.mod h1:9KTHXmSnoGruLpwFjVSX0lNNA75CykiMECbovNTZqGI=
+golang.org/x/sync v0.20.0/go.mod h1:9xrNwdLfx4jkKbNva9FpL6vEN7evnE43NNNJQ2LF3+0=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
@@ -338,26 +338,26 @@ golang.org/x/sys v0.0.0-20220811171246-fbc7d0a398ab/go.mod h1:oPkhp1MJrh7nUepCBc
 golang.org/x/sys v0.2.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.12.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.41.0 h1:Ivj+2Cp/ylzLiEU89QhWblYnOE9zerudt9Ftecq2C6k=
+golang.org/x/sys v0.42.0 h1:omrd2nAlyT5ESRdCLYdm3+fMfNFE/+Rf4bDIQImRJeo=
-golang.org/x/sys v0.41.0/go.mod h1:OgkHotnGiDImocRcuBABYBEXf8A9a87e/uXjp9XT3ks=
+golang.org/x/sys v0.42.0/go.mod h1:4GL1E5IUh+htKOUEOaiffhrAeqysfVGipDYzABqnCmw=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/term v0.0.0-20210927222741-03fcf44c2211/go.mod h1:jbD1KX2456YbFQfuXm/mYQcufACuNUgVhRMnK/tPxf8=
 golang.org/x/term v0.2.0/go.mod h1:TVmDHMZPmdnySmBfhjOoOdhjzdE1h4u1VwSiw2l1Nuc=
-golang.org/x/term v0.40.0 h1:36e4zGLqU4yhjlmxEaagx2KuYbJq3EwY8K943ZsHcvg=
+golang.org/x/term v0.41.0 h1:QCgPso/Q3RTJx2Th4bDLqML4W6iJiaXFq2/ftQF13YU=
-golang.org/x/term v0.40.0/go.mod h1:w2P8uVp06p2iyKKuvXIm7N/y0UCRt3UfJTfZ7oOpglM=
+golang.org/x/term v0.41.0/go.mod h1:3pfBgksrReYfZ5lvYM0kSO0LIkAl4Yl2bXOkKP7Ec2A=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/text v0.3.7/go.mod h1:u+2+/6zg+i71rQMx5EYifcz6MCKuco9NR6JIITiCfzQ=
 golang.org/x/text v0.4.0/go.mod h1:mrYo+phRRbMaCq/xk9113O4dZlRixOauAjOtrjsXDZ8=
-golang.org/x/text v0.34.0 h1:oL/Qq0Kdaqxa1KbNeMKwQq0reLCCaFtqu2eNuSeNHbk=
+golang.org/x/text v0.35.0 h1:JOVx6vVDFokkpaq1AEptVzLTpDe9KGpj5tR4/X+ybL8=
-golang.org/x/text v0.34.0/go.mod h1:homfLqTYRFyVYemLBFl5GgL/DWEiH5wcsQ5gSh1yziA=
+golang.org/x/text v0.35.0/go.mod h1:khi/HExzZJ2pGnjenulevKNX1W67CUy0AsXcNubPGCA=
 golang.org/x/time v0.12.0 h1:ScB/8o8olJvc+CQPWrK3fPZNfh7qgwCrY0zJmoEQLSE=
 golang.org/x/time v0.12.0/go.mod h1:CDIdPxbZBQxdj6cxyCIdrNogrJKMJ7pr37NYpMcMDSg=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
 golang.org/x/tools v0.1.12/go.mod h1:hNGJHUnrk76NpqgfD5Aqm5Crs+Hm0VOH/i9J2+nxYbc=
-golang.org/x/tools v0.41.0 h1:a9b8iMweWG+S0OBnlU36rzLp20z1Rp10w+IY2czHTQc=
+golang.org/x/tools v0.42.0 h1:uNgphsn75Tdz5Ji2q36v/nsFSfR/9BRFvqhGBaJGd5k=
-golang.org/x/tools v0.41.0/go.mod h1:XSY6eDqxVNiYgezAVqqCeihT4j1U2CCsqvH3WhQpnlg=
+golang.org/x/tools v0.42.0/go.mod h1:Ma6lCIwGZvHK6XtgbswSoWroEkhugApmsXyrUmBhfr0=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 google.golang.org/genproto v0.0.0-20250603155806-513f23925822 h1:rHWScKit0gvAPuOnu87KpaYtjK5zBMLcULh7gxkCXu4=
 google.golang.org/genproto/googleapis/api v0.0.0-20250818200422-3122310a409c h1:AtEkQdl5b6zsybXcbz00j1LwNodDuH6hVifIaNqk7NQ=

internal/controller/proxy_controller.go

@@ -1,9 +1,11 @@
 package controller
 
 import (
+	"errors"
 	"fmt"
 	"net/http"
-	"slices"
+	"net/url"
+	"regexp"
 	"strings"
 
 	"github.com/steveiliop56/tinyauth/internal/config"
@@ -15,12 +17,31 @@ import (
 	"github.com/google/go-querystring/query"
 )
 
+type AuthModuleType int
+
+const (
+	AuthRequest AuthModuleType = iota
+	ExtAuthz
+	ForwardAuth
+)
+
+var BrowserUserAgentRegex = regexp.MustCompile("Chrome|Gecko|AppleWebKit|Opera|Edge")
+
 var SupportedProxies = []string{"nginx", "traefik", "caddy", "envoy"}
 
 type Proxy struct {
 	Proxy string `uri:"proxy" binding:"required"`
 }
 
+type ProxyContext struct {
+	Host      string
+	Proto     string
+	Path      string
+	Method    string
+	Type      AuthModuleType
+	IsBrowser bool
+}
+
 type ProxyControllerConfig struct {
 	AppURL string
 }
@@ -43,75 +64,30 @@ func NewProxyController(config ProxyControllerConfig, router *gin.RouterGroup, a
 
 func (controller *ProxyController) SetupRoutes() {
 	proxyGroup := controller.router.Group("/auth")
-	// There is a later check to control allowed methods per proxy
 	proxyGroup.Any("/:proxy", controller.proxyHandler)
 }
 
 func (controller *ProxyController) proxyHandler(c *gin.Context) {
-	var req Proxy
+	// Load proxy context based on the request type
+	proxyCtx, err := controller.getProxyContext(c)
 
-	err := c.BindUri(&req)
 	if err != nil {
-		tlog.App.Error().Err(err).Msg("Failed to bind URI")
+		tlog.App.Warn().Err(err).Msg("Failed to get proxy context")
 		c.JSON(400, gin.H{
 			"status":  400,
-			"message": "Bad Request",
+			"message": "Bad request",
 		})
 		return
 	}
 
-	if !slices.Contains(SupportedProxies, req.Proxy) {
+	tlog.App.Trace().Interface("ctx", proxyCtx).Msg("Got proxy context")
-		tlog.App.Warn().Str("proxy", req.Proxy).Msg("Invalid proxy")
-		c.JSON(400, gin.H{
-			"status":  400,
-			"message": "Bad Request",
-		})
-		return
-	}
-
-	// Only allow GET for non-envoy proxies.
-	// Envoy uses the original client method for the external auth request
-	// so we allow Any standard HTTP method for /api/auth/envoy
-	if req.Proxy != "envoy" && c.Request.Method != http.MethodGet {
-		tlog.App.Warn().Str("method", c.Request.Method).Msg("Invalid method for proxy")
-		c.Header("Allow", "GET")
-		c.JSON(405, gin.H{
-			"status":  405,
-			"message": "Method Not Allowed",
-		})
-		return
-	}
-
-	isBrowser := strings.Contains(c.Request.Header.Get("Accept"), "text/html")
-
-	if isBrowser {
-		tlog.App.Debug().Msg("Request identified as (most likely) coming from a browser")
-	} else {
-		tlog.App.Debug().Msg("Request identified as (most likely) coming from a non-browser client")
-	}
-
-	uri, ok := controller.requireHeader(c, "x-forwarded-uri")
-
-	if !ok {
-		return
-	}
-
-	host, ok := controller.requireHeader(c, "x-forwarded-host")
-	if !ok {
-		return
-	}
-
-	proto, ok := controller.requireHeader(c, "x-forwarded-proto")
-	if !ok {
-		return
-	}
 
 	// Get acls
-	acls, err := controller.acls.GetAccessControls(host)
+	acls, err := controller.acls.GetAccessControls(proxyCtx.Host)
 
 	if err != nil {
 		tlog.App.Error().Err(err).Msg("Failed to get access controls for resource")
-		controller.handleError(c, req, isBrowser)
+		controller.handleError(c, proxyCtx)
 		return
 	}
 
@@ -128,11 +104,11 @@ func (controller *ProxyController) proxyHandler(c *gin.Context) {
 		return
 	}
 
-	authEnabled, err := controller.auth.IsAuthEnabled(uri, acls.Path)
+	authEnabled, err := controller.auth.IsAuthEnabled(proxyCtx.Path, acls.Path)
 
 	if err != nil {
 		tlog.App.Error().Err(err).Msg("Failed to check if auth is enabled for resource")
-		controller.handleError(c, req, isBrowser)
+		controller.handleError(c, proxyCtx)
 		return
 	}
 
@@ -147,7 +123,7 @@ func (controller *ProxyController) proxyHandler(c *gin.Context) {
 	}
 
 	if !controller.auth.CheckIP(acls.IP, clientIP) {
-		if req.Proxy == "nginx" || !isBrowser {
+		if !controller.useFriendlyError(proxyCtx) {
 			c.JSON(401, gin.H{
 				"status":  401,
 				"message": "Unauthorized",
@@ -156,7 +132,7 @@ func (controller *ProxyController) proxyHandler(c *gin.Context) {
 		}
 
 		queries, err := query.Values(config.UnauthorizedQuery{
-			Resource: strings.Split(host, ".")[0],
+			Resource: strings.Split(proxyCtx.Host, ".")[0],
 			IP:       clientIP,
 		})
 
@@ -189,9 +165,9 @@ func (controller *ProxyController) proxyHandler(c *gin.Context) {
 		userAllowed := controller.auth.IsUserAllowed(c, userContext, acls)
 
 		if !userAllowed {
-			tlog.App.Warn().Str("user", userContext.Username).Str("resource", strings.Split(host, ".")[0]).Msg("User not allowed to access resource")
+			tlog.App.Warn().Str("user", userContext.Username).Str("resource", strings.Split(proxyCtx.Host, ".")[0]).Msg("User not allowed to access resource")
 
-			if req.Proxy == "nginx" || !isBrowser {
+			if !controller.useFriendlyError(proxyCtx) {
 				c.JSON(403, gin.H{
 					"status":  403,
 					"message": "Forbidden",
@@ -200,7 +176,7 @@ func (controller *ProxyController) proxyHandler(c *gin.Context) {
 			}
 
 			queries, err := query.Values(config.UnauthorizedQuery{
-				Resource: strings.Split(host, ".")[0],
+				Resource: strings.Split(proxyCtx.Host, ".")[0],
 			})
 
 			if err != nil {
@@ -229,9 +205,9 @@ func (controller *ProxyController) proxyHandler(c *gin.Context) {
 			}
 
 			if !groupOK {
-				tlog.App.Warn().Str("user", userContext.Username).Str("resource", strings.Split(host, ".")[0]).Msg("User groups do not match resource requirements")
+				tlog.App.Warn().Str("user", userContext.Username).Str("resource", strings.Split(proxyCtx.Host, ".")[0]).Msg("User groups do not match resource requirements")
 
-				if req.Proxy == "nginx" || !isBrowser {
+				if !controller.useFriendlyError(proxyCtx) {
 					c.JSON(403, gin.H{
 						"status":  403,
 						"message": "Forbidden",
@@ -240,7 +216,7 @@ func (controller *ProxyController) proxyHandler(c *gin.Context) {
 				}
 
 				queries, err := query.Values(config.UnauthorizedQuery{
-					Resource: strings.Split(host, ".")[0],
+					Resource: strings.Split(proxyCtx.Host, ".")[0],
 					GroupErr: true,
 				})
 
@@ -282,7 +258,7 @@ func (controller *ProxyController) proxyHandler(c *gin.Context) {
 		return
 	}
 
-	if req.Proxy == "nginx" || !isBrowser {
+	if !controller.useFriendlyError(proxyCtx) {
 		c.JSON(401, gin.H{
 			"status":  401,
 			"message": "Unauthorized",
@@ -291,7 +267,7 @@ func (controller *ProxyController) proxyHandler(c *gin.Context) {
 	}
 
 	queries, err := query.Values(config.RedirectQuery{
-		RedirectURI: fmt.Sprintf("%s://%s%s", proto, host, uri),
+		RedirectURI: fmt.Sprintf("%s://%s%s", proxyCtx.Proto, proxyCtx.Host, proxyCtx.Path),
 	})
 
 	if err != nil {
@@ -321,8 +297,8 @@ func (controller *ProxyController) setHeaders(c *gin.Context, acls config.App) {
 	}
 }
 
-func (controller *ProxyController) handleError(c *gin.Context, req Proxy, isBrowser bool) {
+func (controller *ProxyController) handleError(c *gin.Context, proxyCtx ProxyContext) {
-	if req.Proxy == "nginx" || !isBrowser {
+	if !controller.useFriendlyError(proxyCtx) {
 		c.JSON(500, gin.H{
 			"status":  500,
 			"message": "Internal Server Error",
@@ -333,15 +309,179 @@ func (controller *ProxyController) handleError(c *gin.Context, req Proxy, isBrow
 	c.Redirect(http.StatusTemporaryRedirect, fmt.Sprintf("%s/error", controller.config.AppURL))
 }
 
-func (controller *ProxyController) requireHeader(c *gin.Context, header string) (string, bool) {
+func (controller *ProxyController) getHeader(c *gin.Context, header string) (string, bool) {
 	val := c.Request.Header.Get(header)
-	if strings.TrimSpace(val) == "" {
+	return val, strings.TrimSpace(val) != ""
-		tlog.App.Error().Str("header", header).Msg("Header not found")
+}
-		c.JSON(400, gin.H{
+
-			"status":  400,
+func (controller *ProxyController) useFriendlyError(proxyCtx ProxyContext) bool {
-			"message": "Bad Request",
+	return (proxyCtx.Type == ForwardAuth || proxyCtx.Type == ExtAuthz) && proxyCtx.IsBrowser
-		})
+}
-		return "", false
+
-	}
+// Code below is inspired from https://github.com/authelia/authelia/blob/master/internal/handlers/handler_authz.go
-	return val, true
+// and thus it may be subject to Apache 2.0 License
+func (controller *ProxyController) getForwardAuthContext(c *gin.Context) (ProxyContext, error) {
+	host, ok := controller.getHeader(c, "x-forwarded-host")
+
+	if !ok {
+		return ProxyContext{}, errors.New("x-forwarded-host not found")
+	}
+
+	uri, ok := controller.getHeader(c, "x-forwarded-uri")
+
+	if !ok {
+		return ProxyContext{}, errors.New("x-forwarded-uri not found")
+	}
+
+	proto, ok := controller.getHeader(c, "x-forwarded-proto")
+
+	if !ok {
+		return ProxyContext{}, errors.New("x-forwarded-proto not found")
+	}
+
+	// Normally we should only allow GET for forward auth but since it's a fallback
+	// for envoy we should allow everything, not a big deal
+	method := c.Request.Method
+
+	return ProxyContext{
+		Host:   host,
+		Proto:  proto,
+		Path:   uri,
+		Method: method,
+		Type:   ForwardAuth,
+	}, nil
+}
+
+func (controller *ProxyController) getAuthRequestContext(c *gin.Context) (ProxyContext, error) {
+	xOriginalUrl, ok := controller.getHeader(c, "x-original-url")
+
+	if !ok {
+		return ProxyContext{}, errors.New("x-original-url not found")
+	}
+
+	url, err := url.Parse(xOriginalUrl)
+
+	if err != nil {
+		return ProxyContext{}, err
+	}
+
+	host := url.Host
+	proto := url.Scheme
+	path := url.Path
+	method := c.Request.Method
+
+	return ProxyContext{
+		Host:   host,
+		Proto:  proto,
+		Path:   path,
+		Method: method,
+		Type:   AuthRequest,
+	}, nil
+}
+
+func (controller *ProxyController) getExtAuthzContext(c *gin.Context) (ProxyContext, error) {
+	// We hope for the someone to set the x-forwarded-proto header
+	proto, ok := controller.getHeader(c, "x-forwarded-proto")
+
+	if !ok {
+		return ProxyContext{}, errors.New("x-forwarded-proto not found")
+	}
+
+	// It sets the host to the original host, not the forwarded host
+	host := c.Request.URL.Host
+
+	// We get the path from the query string
+	path := c.Query("path")
+
+	// For envoy we need to support every method
+	method := c.Request.Method
+
+	return ProxyContext{
+		Host:   host,
+		Proto:  proto,
+		Path:   path,
+		Method: method,
+		Type:   ExtAuthz,
+	}, nil
+}
+
+func (controller *ProxyController) determineAuthModules(proxy string) []AuthModuleType {
+	switch proxy {
+	case "traefik":
+		return []AuthModuleType{ForwardAuth}
+	case "envoy":
+		return []AuthModuleType{ExtAuthz, ForwardAuth}
+	case "nginx":
+		return []AuthModuleType{AuthRequest, ForwardAuth}
+	default:
+		return []AuthModuleType{ForwardAuth}
+	}
+}
+
+func (controller *ProxyController) getContextFromAuthModule(c *gin.Context, module AuthModuleType) (ProxyContext, error) {
+	switch module {
+	case ForwardAuth:
+		ctx, err := controller.getForwardAuthContext(c)
+		if err != nil {
+			return ProxyContext{}, err
+		}
+		return ctx, nil
+	case ExtAuthz:
+		ctx, err := controller.getExtAuthzContext(c)
+		if err != nil {
+			return ProxyContext{}, err
+		}
+		return ctx, nil
+	case AuthRequest:
+		ctx, err := controller.getAuthRequestContext(c)
+		if err != nil {
+			return ProxyContext{}, err
+		}
+		return ctx, nil
+	}
+	return ProxyContext{}, fmt.Errorf("unsupported auth module: %v", module)
+}
+
+func (controller *ProxyController) getProxyContext(c *gin.Context) (ProxyContext, error) {
+	var req Proxy
+
+	err := c.BindUri(&req)
+	if err != nil {
+		return ProxyContext{}, err
+	}
+
+	tlog.App.Debug().Msgf("Proxy: %v", req.Proxy)
+
+	tlog.App.Trace().Interface("headers", c.Request.Header).Msg("Request headers")
+
+	authModules := controller.determineAuthModules(req.Proxy)
+
+	var ctx ProxyContext
+
+	for _, module := range authModules {
+		tlog.App.Debug().Msgf("Trying auth module: %v", module)
+		ctx, err = controller.getContextFromAuthModule(c, module)
+		if err == nil {
+			tlog.App.Debug().Msgf("Auth module %v succeeded", module)
+			break
+		}
+		tlog.App.Debug().Err(err).Msgf("Auth module %v failed", module)
+	}
+
+	if err != nil {
+		return ProxyContext{}, err
+	}
+
+	// We don't care if the header is empty, we will just assume it's not a browser
+	userAgent, _ := controller.getHeader(c, "user-agent")
+	isBrowser := BrowserUserAgentRegex.MatchString(userAgent)
+
+	if isBrowser {
+		tlog.App.Debug().Msg("Request identified as coming from a browser")
+	} else {
+		tlog.App.Debug().Msg("Request identified as coming from a non-browser client")
+	}
+
+	ctx.IsBrowser = isBrowser
+	return ctx, nil
 }

internal/controller/proxy_controller_test.go

@@ -145,7 +145,7 @@ func TestProxyHandler(t *testing.T) {
 	req = httptest.NewRequest("GET", "/api/auth/nginx", nil)
 	req.Header.Set("X-Forwarded-Proto", "https")
 	req.Header.Set("X-Forwarded-Host", "example.com")
-	req.Header.Set("X-Forwarded-Uri", "/somepath")
+	// we won't set X-Forwarded-Uri to test that the controller can work without it
 	router.ServeHTTP(recorder, req)
 
 	assert.Equal(t, 401, recorder.Code)
@@ -171,7 +171,7 @@ func TestProxyHandler(t *testing.T) {
 	req = httptest.NewRequest("GET", "/api/auth/traefik", nil)
 	req.Header.Set("X-Forwarded-Proto", "https")
 	req.Header.Set("X-Forwarded-Host", "example.com")
-	req.Header.Set("X-Forwarded-Uri", "/somepath")
+	req.Header.Set("X-Original-Uri", "/somepath") // Test with original URI for kubernetes ingress
 	req.Header.Set("Accept", "text/html")
 
 	router.ServeHTTP(recorder, req)