SSH panic when using EC key #316
Description
When I try a simple SSH client with go1.24.5-1-openssl-fips, I get:
Testing SSH connection to gitlab.com:22 as user stanhu...
panic: curve25519: internal error: scalarBaseMult was not 32 bytes
goroutine 10 [running]:
golang.org/x/crypto/curve25519.ScalarBaseMult(0xc00001a460, 0x6a34e0?)
/root/go/pkg/mod/golang.org/x/crypto@v0.41.0/curve25519/curve25519.go:39 +0x13b
golang.org/x/crypto/ssh.(*curve25519KeyPair).generate(0xc00001a440, {0x6a5720?, 0x6a34e0?})
/root/go/pkg/mod/golang.org/x/crypto@v0.41.0/ssh/kex.go:457 +0x65
golang.org/x/crypto/ssh.(*curve25519sha256).Client(0xa048b0?, {0x7f6c0a7f0a00, 0xc000112120}, {0x6a5720, 0x6a34e0}, 0xc0000704e0)
/root/go/pkg/mod/golang.org/x/crypto@v0.41.0/ssh/kex.go:468 +0x6e
golang.org/x/crypto/ssh.(*handshakeTransport).client(0xc000104680, {0x6a5a40?, 0xa4d0e0?}, 0xc0000704e0?)
/root/go/pkg/mod/golang.org/x/crypto@v0.41.0/ssh/handshake.go:826 +0x66
golang.org/x/crypto/ssh.(*handshakeTransport).enterKeyExchange(0xc000104680, {0xc0000d8300, 0x2e7, 0x2e7})
/root/go/pkg/mod/golang.org/x/crypto@v0.41.0/ssh/handshake.go:716 +0x49a
golang.org/x/crypto/ssh.(*handshakeTransport).kexLoop(0xc000104680)
/root/go/pkg/mod/golang.org/x/crypto@v0.41.0/ssh/handshake.go:345 +0x98
created by golang.org/x/crypto/ssh.newClientTransport in goroutine 1
/root/go/pkg/mod/golang.org/x/crypto@v0.41.0/ssh/handshake.go:170 +0x256
Is this similar to 896a14d where EC keys are not disabled in FIPS mode when using SSH?
Reproduction client:
package main
import (
"fmt"
"log"
"os"
"os/user"
"time"
"golang.org/x/crypto/ssh"
)
func main() {
if len(os.Args) < 2 {
fmt.Println("Usage: go run ssh-test.go <host:port> [username]")
fmt.Println("Example: go run ssh-test.go example.com:22")
fmt.Println("Example: go run ssh-test.go 192.168.1.100:2222 myuser")
os.Exit(1)
}
address := os.Args[1]
username := "root" // default
if len(os.Args) > 2 {
username = os.Args[2]
} else {
// Try to get current user
if currentUser, err := user.Current(); err == nil {
username = currentUser.Username
}
}
fmt.Printf("Testing SSH connection to %s as user %s...\n", address, username)
config := &ssh.ClientConfig{
User: username,
Auth: []ssh.AuthMethod{
ssh.Password(""), // Try empty password first
ssh.PasswordCallback(func() (string, error) {
fmt.Print("Enter password: ")
var password string
fmt.Scanln(&password)
return password, nil
}),
},
HostKeyCallback: ssh.InsecureIgnoreHostKey(), // Accept any host key
Timeout: 10 * time.Second,
}
client, err := ssh.Dial("tcp", address, config)
if err != nil {
log.Fatalf("❌ Connection failed: %v", err)
}
defer client.Close()
// Test by running a simple command
session, err := client.NewSession()
if err != nil {
log.Fatalf("❌ Session creation failed: %v", err)
}
defer session.Close()
output, err := session.Output("echo 'SSH connection test successful'")
if err != nil {
log.Fatalf("❌ Command execution failed: %v", err)
}
fmt.Printf("✅ Connection successful!\n")
fmt.Printf("Server response: %s", output)
fmt.Printf("Client version: %s\n", client.ClientVersion())
fmt.Printf("Server version: %s\n", client.ServerVersion())
}