Add gencert function

Makefile.containers

@@ -10,8 +10,8 @@ endif
 
 ifeq ($(CONTAINER_CLITOOL), docker)
 CONTAINER_BUILDENV ?= DOCKER_BUILDKIT=1 BUILDKIT_PROGRESS=plain
-ifeq ($(shell docker-compose -v >/dev/null 2>&1 || echo FAIL),)
-CONTAINER_COMPOSE = docker-compose
+ifeq ($(shell docker -v >/dev/null 2>&1 || echo FAIL),)
+CONTAINER_COMPOSE = docker compose
 endif
 else ifeq ($(CONTAINER_CLITOOL), podman)
 ifeq ($(shell podman-compose -v >/dev/null 2>&1 || echo FAIL),)

internal/collector/otel_collector_plugin.go

@@ -78,6 +78,10 @@ func (oc *Collector) Init(ctx context.Context, mp bus.MessagePipeInterface) erro
 		return fmt.Errorf("write OTel Collector config: %w", err)
 	}
 
+	if oc.config.Collector.Receivers.OtlpReceivers != nil {
+		oc.processReceivers(ctx, oc.config.Collector.Receivers.OtlpReceivers)
+	}
+
 	bootErr := oc.bootup(runCtx)
 	if bootErr != nil {
 		slog.ErrorContext(runCtx, "Unable to start OTel Collector", "error", bootErr)
@@ -86,6 +90,31 @@ func (oc *Collector) Init(ctx context.Context, mp bus.MessagePipeInterface) erro
 	return nil
 }
 
+// Process receivers and log warning for sub-optimal configurations
+func (oc *Collector) processReceivers(ctx context.Context, receivers []config.OtlpReceiver) {
+	for _, receiver := range receivers {
+		if receiver.OtlpTLSConfig == nil {
+			slog.WarnContext(ctx, "OTEL receiver is configured without TLS. Connections are unencrypted.")
+			continue
+		}
+
+		if receiver.OtlpTLSConfig.GenerateSelfSignedCert {
+			slog.WarnContext(ctx,
+				"Self-signed certificate for OTEL receiver requested, "+
+					"this is not recommended for production environments.",
+			)
+
+			if receiver.OtlpTLSConfig.ExistingCert {
+				slog.WarnContext(ctx,
+					"Certificate file already exists, skipping self-signed certificate generation",
+				)
+			}
+		} else {
+			slog.WarnContext(ctx, "OTEL receiver is configured without TLS. Connections are unencrypted.")
+		}
+	}
+}
+
 func (oc *Collector) bootup(ctx context.Context) error {
 	slog.InfoContext(ctx, "Starting OTel collector")
 	errChan := make(chan error)

internal/collector/otelcol.tmpl

@@ -27,10 +27,35 @@ receivers:
     protocols:
       {{- if eq .Server.Type 0 }}
       grpc:
+        endpoint: "{{ .Server.Host }}:{{ .Server.Port }}"
+        {{- if and .OtlpTLSConfig (or (gt (len .OtlpTLSConfig.Key) 0) (gt (len .OtlpTLSConfig.Cert) 0) (gt (len .OtlpTLSConfig.Key) 0)) }}
+        tls:
+          {{ if gt (len .OtlpTLSConfig.Cert) 0 -}}
+          cert_file: {{ .OtlpTLSConfig.Cert }}
+          {{- end }}
+          {{ if gt (len .OtlpTLSConfig.Key) 0 -}}
+          key_file: {{ .OtlpTLSConfig.Key }}
+          {{- end }}
+          {{ if gt (len .OtlpTLSConfig.Ca) 0 -}}
+          ca_file: {{ .OtlpTLSConfig.Ca }}
+          {{- end }}
+        {{- end }}
       {{- else }}
       http:
-      {{- end }}
         endpoint: "{{- .Server.Host -}}:{{- .Server.Port -}}"
+        {{- if .OtlpTLSConfig }}
+        tls:
+          {{ if gt (len .OtlpTLSConfig.Cert) 0 -}}
+          cert_file: {{ .OtlpTLSConfig.Cert }}
+          {{- end }}
+          {{ if gt (len .OtlpTLSConfig.Key) 0 -}}
+          key_file: {{ .OtlpTLSConfig.Key }}
+          {{- end }}
+          {{ if gt (len .OtlpTLSConfig.Ca) 0 -}}
+          ca_file: {{ .OtlpTLSConfig.Ca }}
+          {{- end }}
+        {{- end }}
+      {{- end }}
 {{- end }}
 {{- range .Receivers.NginxReceivers }}
   nginx/{{- .InstanceID -}}:

internal/collector/settings_test.go

@@ -90,6 +90,20 @@ func TestTemplateWrite(t *testing.T) {
 			},
 		},
 	})
+	// Clear default config and test collector with TLS enabled
+	cfg.Collector.Receivers.OtlpReceivers = []config.OtlpReceiver{}
+	cfg.Collector.Receivers.OtlpReceivers = append(cfg.Collector.Receivers.OtlpReceivers, config.OtlpReceiver{
+		Server: &config.ServerConfig{
+			Host: "localhost",
+			Port: 4317,
+			Type: 0,
+		},
+		OtlpTLSConfig: &config.OtlpTLSConfig{
+			Cert: "/tmp/cert.pem",
+			Key:  "/tmp/key.pem",
+			Ca:   "/tmp/ca.pem",
+		},
+	})
 
 	require.NotNil(t, cfg)
 

internal/config/config.go

@@ -12,9 +12,11 @@ import (
 	"log/slog"
 	"os"
 	"path/filepath"
+	"slices"
 	"strings"
 	"time"
 
+	selfsignedcerts "github.com/nginx/agent/v3/pkg/tls"
 	uuidLibrary "github.com/nginx/agent/v3/pkg/uuid"
 	"github.com/spf13/cobra"
 	flag "github.com/spf13/pflag"
@@ -389,6 +391,11 @@ func resolveCollector(allowedDirs []string) (*Collector, error) {
 		Log:        &log,
 	}
 
+	// Check for self-signed certificate true in Agent conf
+	if err = handleSelfSignedCertificates(col); err != nil {
+		return nil, err
+	}
+
 	err = col.Validate(allowedDirs)
 	if err != nil {
 		return nil, fmt.Errorf("collector config: %w", err)
@@ -397,6 +404,57 @@ func resolveCollector(allowedDirs []string) (*Collector, error) {
 	return col, nil
 }
 
+// generate self-signed certificate for OTEL receiver
+// nolint: revive
+func handleSelfSignedCertificates(col *Collector) error {
+	if col.Receivers.OtlpReceivers != nil {
+		for _, receiver := range col.Receivers.OtlpReceivers {
+			if receiver.OtlpTLSConfig != nil && receiver.OtlpTLSConfig.GenerateSelfSignedCert {
+				err := processOtlpReceivers(receiver.OtlpTLSConfig)
+				if err != nil {
+					return fmt.Errorf("failed to generate self-signed certificate: %w", err)
+				}
+			}
+		}
+	}
+
+	return nil
+}
+
+func processOtlpReceivers(tlsConfig *OtlpTLSConfig) error {
+	sanNames := strings.Split(DefCollectorTLSSANNames, ",")
+
+	if tlsConfig.Ca == "" {
+		tlsConfig.Ca = DefCollectorTLSCAPath
+	}
+	if tlsConfig.Cert == "" {
+		tlsConfig.Cert = DefCollectorTLSCertPath
+	}
+	if tlsConfig.Key == "" {
+		tlsConfig.Key = DefCollectorTLSKeyPath
+	}
+
+	if !slices.Contains(sanNames, tlsConfig.ServerName) {
+		sanNames = append(sanNames, tlsConfig.ServerName)
+	}
+	if len(sanNames) > 0 {
+		existingCert, err := selfsignedcerts.GenerateServerCerts(
+			sanNames,
+			tlsConfig.Ca,
+			tlsConfig.Cert,
+			tlsConfig.Key,
+		)
+		if err != nil {
+			return fmt.Errorf("failed to generate self-signed certificate: %w", err)
+		}
+		if existingCert {
+			tlsConfig.ExistingCert = true
+		}
+	}
+
+	return nil
+}
+
 func resolveCommand() *Command {
 	if !viperInstance.IsSet(CommandRootKey) {
 		return nil

internal/config/config_test.go

@@ -367,18 +367,19 @@ func getAgentConfig() *Config {
 					{
 						Server: &ServerConfig{
 							Host: "localhost",
-							Port: 4321,
+							Port: 4317,
 							Type: 0,
 						},
 						Auth: &AuthConfig{
 							Token: "even-secreter-token",
 						},
-						TLS: &TLSConfig{
-							Cert:       "/path/to/server-cert.pem",
-							Key:        "/path/to/server-cert.pem",
-							Ca:         "/path/to/server-cert.pem",
-							SkipVerify: true,
-							ServerName: "local-dataa-plane-server",
+						OtlpTLSConfig: &OtlpTLSConfig{
+							GenerateSelfSignedCert: false,
+							Cert:                   "/path/to/server-cert.pem",
+							Key:                    "/path/to/server-cert.pem",
+							Ca:                     "/path/to/server-cert.pem",
+							SkipVerify:             true,
+							ServerName:             "local-data-plane-server",
 						},
 					},
 				},

internal/config/defaults.go

@@ -14,10 +14,15 @@ const (
 	DefNginxReloadMonitoringPeriod = 10 * time.Second
 	DefTreatErrorsAsWarnings       = true
 
-	DefCollectorConfigPath = "/var/run/nginx-agent/opentelemetry-collector-agent.yaml"
-	DefCollectorLogLevel   = "INFO"
-	DefCollectorLogPath    = "/var/log/nginx-agent/opentelemetry-collector-agent.log"
-	DefConfigDirectories   = "/etc/nginx:/usr/local/etc/nginx:/usr/share/nginx/modules"
+	DefCollectorConfigPath           = "/var/run/nginx-agent/opentelemetry-collector-agent.yaml"
+	DefCollectorTLSGenSelfSignedCert = false
+	DefCollectorLogLevel             = "INFO"
+	DefCollectorLogPath              = "/var/log/nginx-agent/opentelemetry-collector-agent.log"
+	DefConfigDirectories             = "/etc/nginx:/usr/local/etc/nginx:/usr/share/nginx/modules"
+	DefCollectorTLSCertPath          = "/var/lib/nginx-agent/cert.pem"
+	DefCollectorTLSKeyPath           = "/var/lib/nginx-agent/key.pem"
+	DefCollectorTLSCAPath            = "/var/lib/nginx-agent/ca.pem"
+	DefCollectorTLSSANNames          = "127.0.0.1,::1,localhost"
 
 	DefCommandServerHostKey    = ""
 	DefCommandServerPortKey    = 0

internal/config/testdata/nginx-agent.conf

@@ -29,11 +29,11 @@ collector:
           auth:
             Token: "secret-receiver-token"
           tls:
+            generate_self_signed_cert: false
             server_name: "test-local-server"
-            skip_verify: false
-            cert: /path/to/server-cert.pem
-            key: /path/to/server-key.pem
-            ca: /path/to/server-cert.pem
+            ca: /tmp/ca.pem
+            cert: /tmp/cert.pem
+            key: /tmp/key.pem
     nginx_receivers:
         - instance_id: cd7b8911-c2c5-4daf-b311-dbead151d938
           stub_status: "http://localhost:4321/status"

internal/config/types.go

@@ -115,9 +115,9 @@ type (
 	}
 
 	OtlpReceiver struct {
-		Server *ServerConfig `yaml:"-" mapstructure:"server"`
-		Auth   *AuthConfig   `yaml:"-" mapstructure:"auth"`
-		TLS    *TLSConfig    `yaml:"-" mapstructure:"tls"`
+		Server        *ServerConfig  `yaml:"-" mapstructure:"server"`
+		Auth          *AuthConfig    `yaml:"-" mapstructure:"auth"`
+		OtlpTLSConfig *OtlpTLSConfig `yaml:"-" mapstructure:"tls"`
 	}
 
 	NginxReceiver struct {
@@ -186,6 +186,17 @@ type (
 		SkipVerify bool   `yaml:"-" mapstructure:"skip_verify"`
 	}
 
+	// Specialized TLS configuration for OtlpReceiver with self-signed cert generation.
+	OtlpTLSConfig struct {
+		Cert                   string `yaml:"-" mapstructure:"cert"`
+		Key                    string `yaml:"-" mapstructure:"key"`
+		Ca                     string `yaml:"-" mapstructure:"ca"`
+		ServerName             string `yaml:"-" mapstructure:"server_name"`
+		ExistingCert           bool   `yaml:"-"`
+		SkipVerify             bool   `yaml:"-" mapstructure:"skip_verify"`
+		GenerateSelfSignedCert bool   `yaml:"-" mapstructure:"generate_self_signed_cert"`
+	}
+
 	File struct {
 		Location string `yaml:"-" mapstructure:"location"`
 	}