Verfahren zur Sicherung und Wiederherstellung von CA-Schlüsseln und -Zertifikaten.

#!/bin/bash
# ca-backup.sh - CA-Backup erstellen
 
BACKUP_DIR="/backup/pki/$(date +%Y%m%d)"
ENCRYPTION_KEY="/etc/pki/backup-key.pem"  # RSA Public Key für Verschlüsselung
 
mkdir -p "$BACKUP_DIR"
 
# 1. Private Keys (verschlüsselt)
echo "Sichere Private Keys..."
for key in /etc/pki/CA/*.key; do
    keyname=$(basename "$key" .key)
 
    # Mit AES-256 verschlüsseln
    openssl enc -aes-256-cbc -salt -pbkdf2 \
        -in "$key" \
        -out "$BACKUP_DIR/${keyname}.key.enc" \
        -pass file:/etc/pki/backup-passphrase.txt
 
    # Oder mit RSA Public Key (asymmetrisch)
    openssl pkeyutl -encrypt \
        -pubin -inkey "$ENCRYPTION_KEY" \
        -in "$key" \
        -out "$BACKUP_DIR/${keyname}.key.rsa-enc"
done
 
# 2. Zertifikate
echo "Sichere Zertifikate..."
cp /etc/pki/CA/*.pem "$BACKUP_DIR/"
 
# 3. CA-Datenbank
echo "Sichere CA-Datenbank..."
cp /etc/pki/CA/index.txt "$BACKUP_DIR/"
cp /etc/pki/CA/serial "$BACKUP_DIR/"
cp /etc/pki/CA/crlnumber "$BACKUP_DIR/"
 
# 4. Konfiguration
cp /etc/pki/CA/openssl.cnf "$BACKUP_DIR/"
 
# 5. Ausgestellte Zertifikate
tar czf "$BACKUP_DIR/issued-certs.tar.gz" /etc/pki/CA/newcerts/
 
# 6. Checksummen
cd "$BACKUP_DIR"
sha256sum * > SHA256SUMS
 
# 7. Gesamtarchiv (optional)
cd /backup/pki
tar czf "ca-backup-$(date +%Y%m%d).tar.gz" "$(date +%Y%m%d)/"
 
echo "Backup abgeschlossen: $BACKUP_DIR"

#!/bin/bash
# hsm-backup.sh - HSM Key Backup
 
# Luna HSM
/usr/safenet/lunaclient/bin/lunacm << EOF
partition backup
    partition name = ca-partition
    backup file = /backup/hsm/ca-partition-$(date +%Y%m%d).bak
EOF
 
# Thales HSM
nShield-cknfastrc backup --slotlist=0 --output=/backup/hsm/nshield-$(date +%Y%m%d).bak
 
# AWS CloudHSM
aws cloudhsmv2 create-cluster-backup --cluster-id <cluster-id>

#!/bin/bash
# shamir-split.sh - Key auf Treuhänder verteilen
 
KEY_FILE="/etc/pki/CA/root-ca.key"
SHARES=5
THRESHOLD=3
 
# Mit ssss-split (Shamir's Secret Sharing Scheme)
cat "$KEY_FILE" | ssss-split -t $THRESHOLD -n $SHARES -w root-ca
 
# Ergebnis: 5 Dateien (root-ca-1 bis root-ca-5)
# Mindestens 3 werden zur Wiederherstellung benötigt
 
# An Treuhänder verteilen
echo "Verteile Shares an Treuhänder:"
echo "  Share 1 → Treuhänder A"
echo "  Share 2 → Treuhänder B"
echo "  Share 3 → Treuhänder C"
echo "  Share 4 → Off-Site Safe"
echo "  Share 5 → HSM Escrow"

#!/bin/bash
# ca-restore.sh - CA aus Backup wiederherstellen
 
BACKUP_FILE="$1"
RESTORE_DIR="/etc/pki/CA"
 
if [ -z "$BACKUP_FILE" ]; then
    echo "Usage: $0 <backup-file.tar.gz>"
    exit 1
fi
 
echo "=== CA RESTORE ==="
echo "Backup: $BACKUP_FILE"
read -p "Fortfahren? (yes/no): " confirm
[ "$confirm" != "yes" ] && exit 1
 
# 1. Aktuellen Zustand sichern
echo "Sichere aktuellen Zustand..."
mv "$RESTORE_DIR" "${RESTORE_DIR}.pre-restore-$(date +%Y%m%d%H%M%S)"
 
# 2. Backup entpacken
echo "Entpacke Backup..."
mkdir -p "$RESTORE_DIR"
tar xzf "$BACKUP_FILE" -C "$RESTORE_DIR" --strip-components=1
 
# 3. Private Keys entschlüsseln
echo "Entschlüssle Private Keys..."
for enc_key in "$RESTORE_DIR"/*.key.enc; do
    keyname=$(basename "$enc_key" .key.enc)
    openssl enc -aes-256-cbc -d -pbkdf2 \
        -in "$enc_key" \
        -out "$RESTORE_DIR/${keyname}.key" \
        -pass file:/etc/pki/backup-passphrase.txt
    rm "$enc_key"
done
 
# 4. Berechtigungen setzen
chmod 600 "$RESTORE_DIR"/*.key
chmod 644 "$RESTORE_DIR"/*.pem
chown -R root:root "$RESTORE_DIR"
 
# 5. Verifizieren
echo "Verifiziere Wiederherstellung..."
for key in "$RESTORE_DIR"/*.key; do
    cert="${key%.key}.pem"
    if [ -f "$cert" ]; then
        key_mod=$(openssl rsa -in "$key" -noout -modulus 2>/dev/null | md5sum)
        cert_mod=$(openssl x509 -in "$cert" -noout -modulus 2>/dev/null | md5sum)
        if [ "$key_mod" = "$cert_mod" ]; then
            echo "✓ $(basename "$key"): Key/Cert Match"
        else
            echo "✗ $(basename "$key"): MISMATCH!"
        fi
    fi
done
 
# 6. CA-Service starten
echo "Starte CA-Services..."
systemctl start pki-ca
systemctl start ocsp-responder
 
echo "=== RESTORE ABGESCHLOSSEN ==="

#!/bin/bash
# shamir-combine.sh - Key aus Shares wiederherstellen
 
echo "Shamir Share Wiederherstellung"
echo "Mindestens 3 von 5 Shares benötigt"
 
# Shares einsammeln (von Treuhändern)
ssss-combine -t 3 > /tmp/restored-key.tmp << EOF
<Share-1-von-Treuhänder-A>
<Share-2-von-Treuhänder-B>
<Share-3-von-Treuhänder-C>
EOF
 
# Verifizieren
openssl rsa -in /tmp/restored-key.tmp -check -noout
if [ $? -eq 0 ]; then
    echo "Key erfolgreich wiederhergestellt"
    mv /tmp/restored-key.tmp /etc/pki/CA/root-ca.key
    chmod 600 /etc/pki/CA/root-ca.key
else
    echo "FEHLER: Key ungültig!"
    rm /tmp/restored-key.tmp
fi

#!/bin/bash
# verify-backup.sh - Backup-Integrität prüfen
 
BACKUP_DIR="$1"
 
echo "=== Backup-Verification ==="
 
# Checksummen prüfen
cd "$BACKUP_DIR"
sha256sum -c SHA256SUMS
if [ $? -ne 0 ]; then
    echo "FEHLER: Checksum-Mismatch!"
    exit 1
fi
 
# Key/Cert-Paare prüfen
for enc_key in *.key.enc; do
    keyname=$(basename "$enc_key" .key.enc)
    cert="${keyname}.pem"
 
    if [ ! -f "$cert" ]; then
        echo "WARNUNG: Kein Zertifikat für $keyname"
        continue
    fi
 
    # Entschlüsseln und prüfen (temporär)
    openssl enc -aes-256-cbc -d -pbkdf2 \
        -in "$enc_key" \
        -out /tmp/verify.key \
        -pass file:/etc/pki/backup-passphrase.txt
 
    key_mod=$(openssl rsa -in /tmp/verify.key -noout -modulus 2>/dev/null | md5sum)
    cert_mod=$(openssl x509 -in "$cert" -noout -modulus 2>/dev/null | md5sum)
 
    if [ "$key_mod" = "$cert_mod" ]; then
        echo "✓ $keyname: OK"
    else
        echo "✗ $keyname: MISMATCH!"
    fi
 
    rm /tmp/verify.key
done
 
echo "=== Verification abgeschlossen ==="

• Key Ceremony – Sichere Schlüsselgenerierung
• Notfall-Revocation – Bei Kompromittierung
• Betrieb – Tägliche Wartung

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Wolfgang van der Stille @ EMSR DATA d.o.o. - Post-Quantum Cryptography Professional