misc: Merge pull request #332 from devtron-labs/eks-detection

common-lib/cloud-provider-identifier/providers/aws.go

@@ -22,88 +22,272 @@ import (
 	"net/http"
 	"os"
 	"strings"
+	"time"
 
 	"github.com/devtron-labs/common-lib/cloud-provider-identifier/bean"
 	"go.uber.org/zap"
 )
 
 type instanceIdentityResponse struct {
-	ImageID    string `json:"imageId"`
-	InstanceID string `json:"instanceId"`
+	ImageID          string `json:"imageId"`
+	InstanceID       string `json:"instanceId"`
+	AvailabilityZone string `json:"availabilityZone"`
+	Region           string `json:"region"`
+	InstanceType     string `json:"instanceType"`
 }
 
 type IdentifyAmazon struct {
 	Logger *zap.SugaredLogger
 }
 
+// AWS environment variables commonly available in EKS environments
+var awsEnvironmentVariables = []string{
+	"AWS_REGION",
+	"AWS_DEFAULT_REGION",
+	"AWS_ROLE_ARN",
+	"AWS_WEB_IDENTITY_TOKEN_FILE",
+	"AWS_STS_REGIONAL_ENDPOINTS",
+}
+
+// AWS service account token paths for EKS
+var awsServiceAccountPaths = []string{
+	"/var/run/secrets/eks.amazonaws.com/serviceaccount/token",
+	"/var/run/secrets/kubernetes.io/serviceaccount/token",
+}
+
 func (impl *IdentifyAmazon) Identify() (string, error) {
+	// Try multiple detection methods in order of reliability for EKS environments
+
+	// 1. Check AWS environment variables (most reliable for EKS)
+	if impl.checkAWSEnvironmentVariables() {
+		impl.Logger.Infow("AWS detected via environment variables")
+		return bean.Amazon, nil
+	}
+
+	// 2. Check for AWS service account tokens (EKS-specific)
+	if impl.checkAWSServiceAccountTokens() {
+		impl.Logger.Infow("AWS detected via service account tokens")
+		return bean.Amazon, nil
+	}
+
+	// 3. Check /proc/version for AWS-specific information
+	if impl.checkProcVersion() {
+		impl.Logger.Infow("AWS detected via /proc/version")
+		return bean.Amazon, nil
+	}
+
+	// 4. Check DMI system files (backward compatibility for EC2)
+	if impl.checkDMISystemFiles() {
+		impl.Logger.Infow("AWS detected via DMI system files")
+		return bean.Amazon, nil
+	}
+
+	impl.Logger.Debugw("AWS not detected via file-based methods")
+	return bean.Unknown, nil
+}
+
+// checkAWSEnvironmentVariables checks for AWS-specific environment variables
+func (impl *IdentifyAmazon) checkAWSEnvironmentVariables() bool {
+	for _, envVar := range awsEnvironmentVariables {
+		if value := os.Getenv(envVar); value != "" {
+			impl.Logger.Debugw("Found AWS environment variable", "variable", envVar, "value", value)
+			return true
+		}
+	}
+	return false
+}
+
+// checkAWSServiceAccountTokens checks for AWS service account tokens (EKS-specific)
+func (impl *IdentifyAmazon) checkAWSServiceAccountTokens() bool {
+	for _, tokenPath := range awsServiceAccountPaths {
+		if _, err := os.Stat(tokenPath); err == nil {
+			impl.Logger.Debugw("Found AWS service account token", "path", tokenPath)
+			return true
+		}
+	}
+	return false
+}
+
+// checkProcVersion checks /proc/version for AWS-specific information
+func (impl *IdentifyAmazon) checkProcVersion() bool {
+	data, err := os.ReadFile("/proc/version")
+	if err != nil {
+		impl.Logger.Debugw("Could not read /proc/version", "error", err)
+		return false
+	}
+
+	content := strings.ToLower(string(data))
+	awsIndicators := []string{"aws", "amazon", "ec2", "xen"}
+
+	for _, indicator := range awsIndicators {
+		if strings.Contains(content, indicator) {
+			impl.Logger.Debugw("Found AWS indicator in /proc/version", "indicator", indicator)
+			return true
+		}
+	}
+	return false
+}
+
+// checkDMISystemFiles checks DMI system files (backward compatibility)
+func (impl *IdentifyAmazon) checkDMISystemFiles() bool {
 	data, err := os.ReadFile(bean.AmazonSysFile)
 	if err != nil {
-		impl.Logger.Errorw("error while reading file", "error", err)
-		return bean.Unknown, err
+		impl.Logger.Debugw("Could not read DMI system file", "file", bean.AmazonSysFile, "error", err)
+		return false
 	}
+
 	if strings.Contains(string(data), bean.AmazonIdentifierString) {
-		return bean.Amazon, nil
+		impl.Logger.Debugw("Found AWS identifier in DMI system file", "identifier", bean.AmazonIdentifierString)
+		return true
 	}
-	return bean.Unknown, nil
+	return false
 }
 
 func (impl *IdentifyAmazon) IdentifyViaMetadataServer(detected chan<- string) {
-	r := instanceIdentityResponse{}
-	req, err := http.NewRequest("PUT", bean.TokenForAmazonMetadataServerV2, nil)
+	// Create HTTP client with timeout for metadata service
+	client := &http.Client{
+		Timeout: 5 * time.Second,
+	}
+
+	// Try to get IMDSv2 token first
+	token, err := impl.getIMDSv2Token(client)
 	if err != nil {
-		impl.Logger.Errorw("error while creating new request", "error", err)
+		impl.Logger.Debugw("Failed to get IMDSv2 token, trying without token", "error", err)
+		// Fallback: try without token (IMDSv1) for backward compatibility
+		if impl.tryMetadataWithoutToken(client, detected) {
+			return
+		}
 		detected <- bean.Unknown
 		return
 	}
+
+	// Try with IMDSv2 token
+	if impl.tryMetadataWithToken(client, token, detected) {
+		return
+	}
+
+	detected <- bean.Unknown
+}
+
+// getIMDSv2Token gets the IMDSv2 token for metadata service access
+func (impl *IdentifyAmazon) getIMDSv2Token(client *http.Client) (string, error) {
+	req, err := http.NewRequest("PUT", bean.TokenForAmazonMetadataServerV2, nil)
+	if err != nil {
+		return "", err
+	}
 	req.Header.Set("X-aws-ec2-metadata-token-ttl-seconds", "21600")
-	tokenResp, err := http.DefaultClient.Do(req)
+
+	resp, err := client.Do(req)
 	if err != nil {
-		impl.Logger.Errorw("error while requesting", "error", err, "request", req)
-		detected <- bean.Unknown
-		return
+		return "", err
 	}
-	defer tokenResp.Body.Close()
-	token, err := io.ReadAll(tokenResp.Body)
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		return "", err
+	}
+
+	token, err := io.ReadAll(resp.Body)
 	if err != nil {
-		impl.Logger.Errorw("error while reading response body", "error", err, "respBody", tokenResp.Body)
-		detected <- bean.Unknown
-		return
+		return "", err
 	}
-	req, err = http.NewRequest("GET", bean.AmazonMetadataServer, nil)
+
+	return string(token), nil
+}
+
+// tryMetadataWithToken attempts to identify AWS using IMDSv2 with token
+func (impl *IdentifyAmazon) tryMetadataWithToken(client *http.Client, token string, detected chan<- string) bool {
+	req, err := http.NewRequest("GET", bean.AmazonMetadataServer, nil)
 	if err != nil {
-		impl.Logger.Errorw("error while creating new request", "error", err)
-		detected <- bean.Unknown
-		return
+		impl.Logger.Debugw("Error creating metadata request", "error", err)
+		return false
 	}
-	req.Header.Set("X-aws-ec2-metadata-token", string(token))
-	resp, err := http.DefaultClient.Do(req)
+	req.Header.Set("X-aws-ec2-metadata-token", token)
+
+	return impl.processMetadataResponse(client, req, detected)
+}
+
+// tryMetadataWithoutToken attempts to identify AWS using IMDSv1 (fallback)
+func (impl *IdentifyAmazon) tryMetadataWithoutToken(client *http.Client, detected chan<- string) bool {
+	req, err := http.NewRequest("GET", bean.AmazonMetadataServer, nil)
 	if err != nil {
-		impl.Logger.Errorw("error while requesting", "error", err, "request", req)
-		detected <- bean.Unknown
-		return
+		impl.Logger.Debugw("Error creating metadata request", "error", err)
+		return false
 	}
-	if resp.StatusCode == http.StatusOK {
-		defer resp.Body.Close()
-		body, err := io.ReadAll(resp.Body)
-		if err != nil {
-			impl.Logger.Errorw("error while reading response body", "error", err, "respBody", resp.Body)
-			detected <- bean.Unknown
-			return
-		}
-		err = json.Unmarshal(body, &r)
-		if err != nil {
-			impl.Logger.Errorw("error while unmarshaling json", "error", err, "body", body)
-			detected <- bean.Unknown
-			return
-		}
-		if strings.HasPrefix(r.ImageID, "ami-") &&
-			strings.HasPrefix(r.InstanceID, "i-") {
-			detected <- bean.Amazon
-			return
-		}
-	} else {
-		detected <- bean.Unknown
-		return
+
+	return impl.processMetadataResponse(client, req, detected)
+}
+
+// processMetadataResponse processes the metadata service response and determines if it's AWS
+func (impl *IdentifyAmazon) processMetadataResponse(client *http.Client, req *http.Request, detected chan<- string) bool {
+	resp, err := client.Do(req)
+	if err != nil {
+		impl.Logger.Debugw("Error requesting metadata", "error", err)
+		return false
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		impl.Logger.Debugw("Metadata service returned non-200 status", "status", resp.StatusCode)
+		return false
+	}
+
+	body, err := io.ReadAll(resp.Body)
+	if err != nil {
+		impl.Logger.Debugw("Error reading metadata response", "error", err)
+		return false
+	}
+
+	var r instanceIdentityResponse
+	err = json.Unmarshal(body, &r)
+	if err != nil {
+		impl.Logger.Debugw("Error unmarshaling metadata response", "error", err, "body", string(body))
+		return false
+	}
+
+	// Enhanced AWS detection logic for EKS compatibility
+	isAWS := false
+
+	// Traditional EC2 detection (backward compatibility)
+	if strings.HasPrefix(r.ImageID, "ami-") && strings.HasPrefix(r.InstanceID, "i-") {
+		impl.Logger.Debugw("AWS detected via traditional EC2 metadata", "imageId", r.ImageID, "instanceId", r.InstanceID)
+		isAWS = true
+	}
+
+	// EKS/Fargate detection - check for AWS region format
+	if r.Region != "" && impl.isValidAWSRegion(r.Region) {
+		impl.Logger.Debugw("AWS detected via region metadata", "region", r.Region)
+		isAWS = true
+	}
+
+	// Check availability zone format (AWS-specific)
+	if r.AvailabilityZone != "" && impl.isValidAWSAvailabilityZone(r.AvailabilityZone) {
+		impl.Logger.Debugw("AWS detected via availability zone", "az", r.AvailabilityZone)
+		isAWS = true
+	}
+
+	if isAWS {
+		detected <- bean.Amazon
+		return true
+	}
+
+	return false
+}
+
+// isValidAWSRegion checks if the region follows AWS region naming convention
+func (impl *IdentifyAmazon) isValidAWSRegion(region string) bool {
+	// AWS regions follow pattern: us-east-1, eu-west-1, ap-southeast-2, etc.
+	parts := strings.Split(region, "-")
+	return len(parts) >= 3 && len(parts[len(parts)-1]) == 1
+}
+
+// isValidAWSAvailabilityZone checks if the AZ follows AWS AZ naming convention
+func (impl *IdentifyAmazon) isValidAWSAvailabilityZone(az string) bool {
+	// AWS AZs follow pattern: us-east-1a, eu-west-1b, etc.
+	if len(az) < 4 {
+		return false
 	}
+	// Should end with a single letter
+	lastChar := az[len(az)-1]
+	return lastChar >= 'a' && lastChar <= 'z'
 }