rewrite: Fix a double-encode issue when using the `{uri}` placeholder (#4516)

Francis Lavoie committed Jan 13, 2022 at 12:17 UTC 1feb65952acd814f9abcfb8e38f727f4e49e9e68

2 files changed +28

modules/caddyhttp/rewrite/rewrite.go

+13

@@ -168,7 +168,20 @@ func (rewr Rewrite) rewrite(r *http.Request, repl *caddy.Replacer, logger *zap.L

168 // in a temporary variable so that they all read the

169 // same version of the URI

170 var newPath, newQuery, newFrag string

171 +

172 if path != "" {

173 + // Since the 'uri' placeholder performs a URL-encode,

174 + // we need to intercept it so that it doesn't, because

175 + // otherwise we risk a double-encode of the path.

176 + uriPlaceholder := "{http.request.uri}"

177 + if strings.Contains(path, uriPlaceholder) {

178 + tmpUri := r.URL.Path

179 + if r.URL.RawQuery != "" {

180 + tmpUri += "?" + r.URL.RawQuery

181 + }

182 + path = strings.ReplaceAll(path, uriPlaceholder, tmpUri)

183 + }

184 +

185 newPath = repl.ReplaceAll(path, "")

186 }

187

modules/caddyhttp/rewrite/rewrite_test.go

+15

@@ -189,6 +189,21 @@ func TestRewrite(t *testing.T) {

189 input: newRequest(t, "GET", "/foo/?a=b"),

190 expect: newRequest(t, "GET", "/foo/bar?c=d"),

191 },

192 + {

193 + rule: Rewrite{URI: "/i{http.request.uri}"},

194 + input: newRequest(t, "GET", "/%C2%B7%E2%88%B5.png"),

195 + expect: newRequest(t, "GET", "/i/%C2%B7%E2%88%B5.png"),

196 + },

197 + {

198 + rule: Rewrite{URI: "/i{http.request.uri}"},

199 + input: newRequest(t, "GET", "/·∵.png?a=b"),

200 + expect: newRequest(t, "GET", "/i/%C2%B7%E2%88%B5.png?a=b"),

201 + },

202 + {

203 + rule: Rewrite{URI: "/i{http.request.uri}"},

204 + input: newRequest(t, "GET", "/%C2%B7%E2%88%B5.png?a=b"),

205 + expect: newRequest(t, "GET", "/i/%C2%B7%E2%88%B5.png?a=b"),

206 + },

207

208 {

209 rule: Rewrite{StripPathPrefix: "/prefix"},