lego/providers/dns/exec/exec.go
2023-05-05 09:49:38 +02:00

126 lines
3.6 KiB
Go

// Package exec implements a DNS provider which runs a program for adding/removing the DNS record.
package exec
import (
"context"
"errors"
"fmt"
"os"
"os/exec"
"time"
"github.com/go-acme/lego/v4/challenge/dns01"
"github.com/go-acme/lego/v4/log"
"github.com/go-acme/lego/v4/platform/config/env"
)
// Environment variables names.
const (
envNamespace = "EXEC_"
EnvPath = envNamespace + "PATH"
EnvMode = envNamespace + "MODE"
EnvPropagationTimeout = envNamespace + "PROPAGATION_TIMEOUT"
EnvPollingInterval = envNamespace + "POLLING_INTERVAL"
EnvSequenceInterval = envNamespace + "SEQUENCE_INTERVAL"
)
// Config Provider configuration.
type Config struct {
Program string
Mode string
PropagationTimeout time.Duration
PollingInterval time.Duration
SequenceInterval time.Duration
}
// NewDefaultConfig returns a default configuration for the DNSProvider.
func NewDefaultConfig() *Config {
return &Config{
PropagationTimeout: env.GetOrDefaultSecond(EnvPropagationTimeout, dns01.DefaultPropagationTimeout),
PollingInterval: env.GetOrDefaultSecond(EnvPollingInterval, dns01.DefaultPollingInterval),
SequenceInterval: env.GetOrDefaultSecond(EnvSequenceInterval, dns01.DefaultPropagationTimeout),
}
}
// DNSProvider implements the challenge.Provider interface.
type DNSProvider struct {
config *Config
}
// NewDNSProvider returns a new DNS provider which runs the program in the
// environment variable EXEC_PATH for adding and removing the DNS record.
func NewDNSProvider() (*DNSProvider, error) {
values, err := env.Get(EnvPath)
if err != nil {
return nil, fmt.Errorf("exec: %w", err)
}
config := NewDefaultConfig()
config.Program = values[EnvPath]
config.Mode = os.Getenv(EnvMode)
return NewDNSProviderConfig(config)
}
// NewDNSProviderConfig returns a new DNS provider which runs the given configuration
// for adding and removing the DNS record.
func NewDNSProviderConfig(config *Config) (*DNSProvider, error) {
if config == nil {
return nil, errors.New("exec: the configuration is nil")
}
return &DNSProvider{config: config}, nil
}
// Present creates a TXT record to fulfill the dns-01 challenge.
func (d *DNSProvider) Present(domain, token, keyAuth string) error {
err := d.run(context.Background(), "present", domain, token, keyAuth)
if err != nil {
return fmt.Errorf("exec: %w", err)
}
return nil
}
// CleanUp removes the TXT record matching the specified parameters.
func (d *DNSProvider) CleanUp(domain, token, keyAuth string) error {
err := d.run(context.Background(), "cleanup", domain, token, keyAuth)
if err != nil {
return fmt.Errorf("exec: %w", err)
}
return nil
}
// Timeout returns the timeout and interval to use when checking for DNS propagation.
// Adjusting here to cope with spikes in propagation times.
func (d *DNSProvider) Timeout() (timeout, interval time.Duration) {
return d.config.PropagationTimeout, d.config.PollingInterval
}
// Sequential All DNS challenges for this provider will be resolved sequentially.
// Returns the interval between each iteration.
func (d *DNSProvider) Sequential() time.Duration {
return d.config.SequenceInterval
}
func (d *DNSProvider) run(ctx context.Context, command, domain, token, keyAuth string) error {
var args []string
if d.config.Mode == "RAW" {
args = []string{command, "--", domain, token, keyAuth}
} else {
info := dns01.GetChallengeInfo(domain, keyAuth)
args = []string{command, info.EffectiveFQDN, info.Value}
}
cmd := exec.CommandContext(ctx, d.config.Program, args...)
output, err := cmd.CombinedOutput()
if len(output) > 0 {
log.Println(string(output))
}
return err
}