Skip to content

Commit

Permalink
Move AWS hostname support behind new flag
Browse files Browse the repository at this point in the history 
For now, the new flag is automatically set when cloud-provider-name=aws, but this will be removed in the future following our normal deprecation timeline.

This also adds IMDSv2 support, and support for setting the hostname on windows.

Signed-off-by: Brad Davidson <brad.davidson@rancher.com>
  • Loading branch information
@brandond
brandond committed Nov 26, 2024
1 parent eb5768b commit 030b9d2
Show file tree
Hide file tree
Showing 4 changed files with 118 additions and 50 deletions.
6 changes: 6 additions & 0 deletions pkg/cli/cmds/root.go
View file
Original file line number Diff line number Diff line change
Expand Up @@ -82,6 +82,12 @@ var (
EnvVar: "RKE2_CLOUD_PROVIDER_CONFIG",
Destination: &config.CloudProviderConfig,
},
&cli.BoolFlag{
Name: "node-name-from-cloud-provider-metadata",
Usage: "(cloud provider) Set node name from instance metadata service hostname",
EnvVar: "RKE2_NODE_NAME_FROM_CLOUD_PROVIDER_METADATA",
Destination: &config.CloudProviderMetadataHostname,
},
&cli.StringFlag{
Name: "profile",
Usage: "(security) Validate system configuration against the selected benchmark (valid items: cis)",
Expand Down
55 changes: 55 additions & 0 deletions pkg/rke2/rke2.go
View file
Original file line number Diff line number Diff line change
Expand Up @@ -4,6 +4,7 @@ import (
"context"
"fmt"
"io/ioutil"
"net/http"
"os"
"os/exec"
"path/filepath"
Expand Down Expand Up @@ -36,6 +37,7 @@ type Config struct {
PodSecurityAdmissionConfigFile string
CloudProviderConfig string
CloudProviderName string
CloudProviderMetadataHostname bool
Images images.ImageOverrideConfig
KubeletPath string
ControlPlaneResourceRequests cli.StringSlice
Expand Down Expand Up @@ -406,3 +408,56 @@ func terminateRunningContainers(ctx context.Context, containerRuntimeEndpoint st
return len(disabledItems) == 0, nil
})
}

func hostnameFromMetadataEndpoint(ctx context.Context) string {
var token string

// Get token, required for IMDSv2
tokenCtx, tokenCancel := context.WithTimeout(ctx, time.Second)
defer tokenCancel()
if req, err := http.NewRequestWithContext(tokenCtx, http.MethodPut, "http://169.254.169.254/latest/api/token", nil); err != nil {
logrus.Debugf("Failed to create request for token endpoint: %v", err)
} else {
req.Header.Add("x-aws-ec2-metadata-token-ttl-seconds", "60")
if resp, err := http.DefaultClient.Do(req); err != nil {
logrus.Debugf("Failed to get token from token endpoint: %v", err)
} else {
defer resp.Body.Close()
if resp.StatusCode != http.StatusOK {
logrus.Debugf("Token endpoint returned unacceptable status code %d", resp.StatusCode)
} else {
if b, err := ioutil.ReadAll(resp.Body); err != nil {
logrus.Debugf("Failed to read response body from token endpoint: %v", err)
} else {
token = string(b)
}
}
}
}

// Get hostname from IMDS, with token if available
metaCtx, metaCancel := context.WithTimeout(ctx, time.Second)
defer metaCancel()
if req, err := http.NewRequestWithContext(metaCtx, http.MethodGet, "http://169.254.169.254/latest/meta-data/local-hostname", nil); err != nil {
logrus.Debugf("Failed to create request for metadata endpoint: %v", err)
} else {
if token != "" {
req.Header.Add("x-aws-ec2-metadata-token", token)
}
if resp, err := http.DefaultClient.Do(req); err != nil {
logrus.Debugf("Failed to get hostname from metadata endpoint: %v", err)
} else {
defer resp.Body.Close()
if resp.StatusCode != http.StatusOK {
logrus.Debugf("Metadata endpoint returned unacceptable status code %d", resp.StatusCode)
} else {
if b, err := ioutil.ReadAll(resp.Body); err != nil {
logrus.Debugf("Failed to read response body from metadata endpoint: %v", err)
} else {
return strings.TrimSpace(string(b))
}
}
}
}
return ""
}
67 changes: 20 additions & 47 deletions pkg/rke2/rke2_linux.go
View file
Original file line number Diff line number Diff line change
Expand Up @@ -7,13 +7,10 @@ import (
"bytes"
"context"
"fmt"
"io/ioutil"
"net/http"
"os/exec"
"path/filepath"
"strconv"
"strings"
"time"

"github.com/k3s-io/k3s/pkg/agent/config"
"github.com/k3s-io/k3s/pkg/cli/cmds"
Expand Down Expand Up @@ -92,22 +89,29 @@ func initExecutor(clx *cli.Context, cfg Config, isServer bool) (*podexecutor.Sta
return nil, fmt.Errorf("--cloud-provider-config requires --cloud-provider-name to be provided")
}
if cfg.CloudProviderName != "" {
cpConfig = &podexecutor.CloudProviderConfig{
Name: cfg.CloudProviderName,
Path: cfg.CloudProviderConfig,
}
if clx.String("node-name") == "" && cfg.CloudProviderName == "aws" {
fqdn := hostnameFromMetadataEndpoint(context.Background())
if fqdn == "" {
hostFQDN, err := hostnameFQDN()
if err != nil {
return nil, err
}
fqdn = hostFQDN
if cfg.CloudProviderName == "aws" {
logrus.Warnf("--cloud-provider-name=aws is deprecated due to removal of the in-tree aws cloud provider; if you want the legacy hostname behavior associated with this flag please use --node-name-from-cloud-provider-metadata")
cfg.CloudProviderMetadataHostname = true
cfg.CloudProviderName = ""
} else {
cpConfig = &podexecutor.CloudProviderConfig{
Name: cfg.CloudProviderName,
Path: cfg.CloudProviderConfig,
}
if err := clx.Set("node-name", fqdn); err != nil {
}
}

if cfg.CloudProviderMetadataHostname {
fqdn := hostnameFromMetadataEndpoint(context.Background())
if fqdn == "" {
hostFQDN, err := hostnameFQDN()
if err != nil {
return nil, err
}
fqdn = hostFQDN
}
if err := clx.Set("node-name", fqdn); err != nil {
return nil, err
}
}

Expand Down Expand Up @@ -502,34 +506,3 @@ func hostnameFQDN() (string, error) {

return strings.TrimSpace(b.String()), nil
}

func hostnameFromMetadataEndpoint(ctx context.Context) string {
ctx, cancel := context.WithTimeout(ctx, time.Second)
defer cancel()

req, err := http.NewRequestWithContext(ctx, http.MethodGet, "http://169.254.169.254/latest/meta-data/local-hostname", nil)
if err != nil {
logrus.Debugf("Failed to create request for metadata endpoint: %v", err)
return ""
}

resp, err := http.DefaultClient.Do(req)
if err != nil {
logrus.Debugf("Failed to get local-hostname from metadata endpoint: %v", err)
return ""
}
defer resp.Body.Close()

if resp.StatusCode != http.StatusOK {
logrus.Debugf("Metadata endpoint returned unacceptable status code %d", resp.StatusCode)
return ""
}

b, err := ioutil.ReadAll(resp.Body)
if err != nil {
logrus.Debugf("Failed to read response body from metadata endpoint: %v", err)
return ""
}

return strings.TrimSpace(string(b))
}
40 changes: 37 additions & 3 deletions pkg/rke2/rke2_windows.go
View file
Original file line number Diff line number Diff line change
Expand Up @@ -4,8 +4,10 @@
package rke2

import (
"context"
"fmt"
"path/filepath"
"unsafe"

"github.com/k3s-io/k3s/pkg/agent/config"
"github.com/k3s-io/k3s/pkg/cli/cmds"
Expand All @@ -15,7 +17,9 @@ import (
"github.com/rancher/rke2/pkg/cli/defaults"
"github.com/rancher/rke2/pkg/images"
"github.com/rancher/rke2/pkg/pebinaryexecutor"
"github.com/sirupsen/logrus"
"github.com/urfave/cli"
"golang.org/x/sys/windows"
)

func initExecutor(clx *cli.Context, cfg Config, isServer bool) (*pebinaryexecutor.PEBinaryConfig, error) {
Expand Down Expand Up @@ -48,9 +52,29 @@ func initExecutor(clx *cli.Context, cfg Config, isServer bool) (*pebinaryexecuto
return nil, fmt.Errorf("--cloud-provider-config requires --cloud-provider-name to be provided")
}
if cfg.CloudProviderName != "" {
cpConfig = &pebinaryexecutor.CloudProviderConfig{
Name: cfg.CloudProviderName,
Path: cfg.CloudProviderConfig,
if cfg.CloudProviderName == "aws" {
logrus.Warnf("--cloud-provider-name=aws is deprecated due to removal of the in-tree aws cloud provider; if you want the legacy node-name behavior associated with this flag please use --node-name-from-cloud-provider-metadata")
cfg.CloudProviderMetadataHostname = true
cfg.CloudProviderName = ""
} else {
cpConfig = &pebinaryexecutor.CloudProviderConfig{
Name: cfg.CloudProviderName,
Path: cfg.CloudProviderConfig,
}
}
}

if cfg.CloudProviderMetadataHostname {
fqdn := hostnameFromMetadataEndpoint(context.Background())
if fqdn == "" {
hostFQDN, err := hostnameFQDN()
if err != nil {
return nil, err
}
fqdn = hostFQDN
}
if err := clx.Set("node-name", fqdn); err != nil {
return nil, err
}
}

Expand Down Expand Up @@ -78,3 +102,13 @@ func initExecutor(clx *cli.Context, cfg Config, isServer bool) (*pebinaryexecuto
CNIName: "",
}, nil
}

func hostnameFQDN() (string, error) {
var domainName *uint16
var domainNameLen uint32 = 256
err := windows.GetComputerNameEx(windows.ComputerNameDnsFullyQualified, &domainName, &domainNameLen)
if err != nil {
return "", err
}
return windows.UTF16ToString((*[1 << 16]uint16)(unsafe.Pointer(domainName))[:domainNameLen-1]), nil
}

0 comments on commit 030b9d2

Please sign in to comment.