Anthropic-Cybersecurity-Skills/skills/configuring-certificate-authority-with-openssl/references/workflows.md

Workflows - Certificate Authority with OpenSSL

Workflow 1: Build Two-Tier CA Hierarchy

[Generate Root CA Key] (RSA 4096 / ECDSA P-384)
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[Create Root CA Self-Signed Certificate]
(validity: 20 years, basicConstraints: CA:TRUE)
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[Store Root CA Key Offline]
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[Generate Intermediate CA Key]
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[Create Intermediate CA CSR]
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[Sign Intermediate CSR with Root CA]
(pathLenConstraint: 0, keyUsage: keyCertSign, cRLSign)
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[Create CA Chain Bundle]
(intermediate.crt + root.crt)

Workflow 2: Issue End-Entity Certificate

[Applicant Generates Key + CSR]
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[Submit CSR to Intermediate CA]
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[Validate CSR]
(check subject, SAN, key strength)
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[Sign with Intermediate CA Key]
(basicConstraints: CA:FALSE)
(extendedKeyUsage: serverAuth / clientAuth)
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[Issue Certificate]
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[Record in Certificate Database]

Workflow 3: Certificate Revocation

[Revocation Request]
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[Verify Authorization]
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[Revoke Certificate]
(record serial number + reason + date)
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[Generate Updated CRL]
(sign with CA key, set nextUpdate)
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[Publish CRL to Distribution Point]
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[Update OCSP Responder Database]

Workflow 4: OpenSSL CA Commands

# 1. Create CA directory structure
mkdir -p ca/{certs,crl,newcerts,private}
touch ca/index.txt
echo 1000 > ca/serial
echo 1000 > ca/crlnumber

# 2. Generate Root CA
openssl genrsa -aes256 -out ca/private/ca.key 4096
openssl req -config ca/openssl.cnf -key ca/private/ca.key \
    -new -x509 -days 7300 -sha256 -extensions v3_ca -out ca/certs/ca.crt

# 3. Generate Intermediate CA
openssl genrsa -aes256 -out intermediate/private/intermediate.key 4096
openssl req -config intermediate/openssl.cnf \
    -key intermediate/private/intermediate.key -new -sha256 -out intermediate/csr/intermediate.csr
openssl ca -config ca/openssl.cnf -extensions v3_intermediate_ca \
    -days 3650 -notext -md sha256 -in intermediate/csr/intermediate.csr \
    -out intermediate/certs/intermediate.crt

# 4. Issue server certificate
openssl req -config intermediate/openssl.cnf \
    -key server.key -new -sha256 -out server.csr
openssl ca -config intermediate/openssl.cnf -extensions server_cert \
    -days 365 -notext -md sha256 -in server.csr -out server.crt