feat: add replay protection plugin (#1672)

Co-authored-by: hanxiantao <601803023@qq.com>

plugins/wasm-go/extensions/replay-protection/main.go

@@ -0,0 +1,77 @@
+package main
+
+import (
+	"fmt"
+
+	"github.com/alibaba/higress/plugins/wasm-go/pkg/wrapper"
+	"github.com/higress-group/proxy-wasm-go-sdk/proxywasm"
+	"github.com/higress-group/proxy-wasm-go-sdk/proxywasm/types"
+	"github.com/tidwall/resp"
+	"replay-protection/config"
+	"replay-protection/util"
+)
+
+func main() {
+	wrapper.SetCtx(
+		"replay-protection",
+		wrapper.ParseConfigBy(config.ParseConfig),
+		wrapper.ProcessRequestHeadersBy(onHttpRequestHeaders),
+	)
+}
+
+func onHttpRequestHeaders(ctx wrapper.HttpContext, cfg config.ReplayProtectionConfig, log wrapper.Log) types.Action {
+	nonce, _ := proxywasm.GetHttpRequestHeader(cfg.NonceHeader)
+	if cfg.ForceNonce && nonce == "" {
+		// In force mode, reject the request if a required header is missing.
+		// Do not return the specific header name in the response.
+		log.Warnf("missing nonce header")
+		proxywasm.SendHttpResponse(400, nil, []byte("Missing Required Header"), -1)
+		return types.ActionPause
+	}
+
+	// If there is no nonce, pass through directly (when not in force mode)
+	if nonce == "" {
+		return types.ActionContinue
+	}
+
+	if err := validateNonce(nonce, &cfg); err != nil {
+		log.Warnf("invalid nonce: %v", err)
+		proxywasm.SendHttpResponse(400, nil, []byte("Invalid Nonce"), -1)
+		return types.ActionPause
+	}
+
+	redisKey := fmt.Sprintf("%s:%s", cfg.Redis.KeyPrefix, nonce)
+
+	// Check if the nonce already exists
+	err := cfg.Redis.Client.SetNX(redisKey, "1", cfg.NonceTTL, func(response resp.Value) {
+		if response.Error() != nil {
+			log.Errorf("redis call error: %v", response.Error())
+			proxywasm.ResumeHttpRequest()
+		} else if response.String() != "OK" {
+			log.Warnf("duplicate nonce detected: %s", nonce)
+			proxywasm.SendHttpResponse(cfg.RejectCode, nil, []byte(cfg.RejectMsg), -1)
+		} else {
+			proxywasm.ResumeHttpRequest()
+		}
+	})
+
+	if err != nil {
+		log.Errorf("redis call failed: %v", err)
+		return types.ActionContinue
+	}
+	return types.ActionPause
+}
+
+func validateNonce(nonce string, cfg *config.ReplayProtectionConfig) error {
+	nonceLength := len(nonce)
+	if nonceLength < cfg.NonceMinLen || nonceLength > cfg.NonceMaxLen {
+		return fmt.Errorf("invalid nonce length: must be between %d and %d",
+			cfg.NonceMinLen, cfg.NonceMaxLen)
+	}
+
+	if cfg.ValidateBase64 && !util.IsValidBase64(nonce) {
+		return fmt.Errorf("invalid nonce format: must be base64 encoded")
+	}
+
+	return nil
+}