Implement authentication

api/handlers/middleware/authentication.go

@@ -0,0 +1,62 @@
+package middleware
+
+import (
+	"fmt"
+	"net/url"
+	"strings"
+
+	"github.com/gin-gonic/gin"
+	"github.com/pikami/cosmium/api/config"
+	"github.com/pikami/cosmium/internal/authentication"
+)
+
+func Authentication() gin.HandlerFunc {
+	return func(c *gin.Context) {
+		requestUrl := c.Request.URL.String()
+		if config.Config.DisableAuth || strings.HasPrefix(requestUrl, "/_explorer") {
+			return
+		}
+
+		var resourceType string
+		parts := strings.Split(requestUrl, "/")
+		switch len(parts) {
+		case 2, 3:
+			resourceType = parts[1]
+		case 4, 5:
+			resourceType = parts[3]
+		case 6, 7:
+			resourceType = parts[5]
+		}
+
+		databaseId, _ := c.Params.Get("databaseId")
+		collId, _ := c.Params.Get("collId")
+		docId, _ := c.Params.Get("docId")
+		var resourceId string
+		if databaseId != "" {
+			resourceId += "dbs/" + databaseId
+		}
+		if collId != "" {
+			resourceId += "/colls/" + collId
+		}
+		if docId != "" {
+			resourceId += "/docs/" + docId
+		}
+
+		authHeader := c.Request.Header.Get("authorization")
+		date := c.Request.Header.Get("x-ms-date")
+		expectedSignature := authentication.GenerateSignature(
+			c.Request.Method, resourceType, resourceId, date, config.Config.AccountKey)
+
+		decoded, _ := url.QueryUnescape(authHeader)
+		params, _ := url.ParseQuery(decoded)
+		clientSignature := strings.Replace(params.Get("sig"), " ", "+", -1)
+		if clientSignature != expectedSignature {
+			fmt.Printf("Got wrong signature from client.\n- Expected: %s\n- Got: %s\n", expectedSignature, clientSignature)
+			c.IndentedJSON(401, gin.H{
+				"code":    "Unauthorized",
+				"message": "Wrong signature.",
+			})
+			c.Abort()
+		}
+	}
+}