From 7afd00dc4aabe5c0711bdd745092f51785dcca1f Mon Sep 17 00:00:00 2001 From: Manuel Thalmann Date: Fri, 3 Nov 2023 14:31:30 +0100 Subject: [PATCH] Add guide for certificate lab --- .gitignore | 1 + Lab 2 - Certificates/README.md | 276 +++++++++++++++++++++++++++++++++ 2 files changed, 277 insertions(+) create mode 100644 .gitignore create mode 100644 Lab 2 - Certificates/README.md diff --git a/.gitignore b/.gitignore new file mode 100644 index 0000000..cfaad76 --- /dev/null +++ b/.gitignore @@ -0,0 +1 @@ +*.pem diff --git a/Lab 2 - Certificates/README.md b/Lab 2 - Certificates/README.md new file mode 100644 index 0000000..367135a --- /dev/null +++ b/Lab 2 - Certificates/README.md @@ -0,0 +1,276 @@ +# Lab 02 - Certificates +## Create Working Environment +```sh +mkdir -p /root/ca +cd /root/ca +mkdir certs crl newcerts private +chmod 700 private +``` + +## Create Private Key +```sh +openssl genpkey -algorithm RSA -pkeyopt rsa_keygen_bits:2048 -out private/ca.key.pem +``` + +## Create Public Key +```sh +openssl pkey -in private/ca.key.pem -out ca.key.pem.pub -pubout +``` + +## Create Certificate Authority +Run using `sudo -i`: + +```sh +touch index.txt +echo 1000 > serial +``` + +Create OpenSSL config: + +```sh +vi /root/ca/openssl.cnf +``` + +***`/root/ca/openssl.cnf`:*** + +```ini +# OpenSSL root CA configuration file. +# Copy to `/root/ca/openssl.cnf`. + +[ ca ] +# `man ca` +default_ca = CA_default + +[ CA_default ] +# Directory and file locations. +dir = /root/ca +certs = $dir/certs +crl_dir = $dir/crl +new_certs_dir = $dir/newcerts +database = $dir/index.txt +serial = $dir/serial +RANDFILE = $dir/private/.rand + +# The root key and root certificate. +private_key = $dir/private/ca.key.pem +certificate = $dir/certs/ca.cert.pem + +# For certificate revocation lists. +crlnumber = $dir/crlnumber +crl = $dir/crl/ca.crl.pem +crl_extensions = crl_ext +default_crl_days = 30 + +# SHA-1 is deprecated, so use SHA-2 instead. +default_md = sha256 + +name_opt = ca_default +cert_opt = ca_default +default_days = 375 +preserve = no +policy = policy_strict + +[ policy_strict ] +# The root CA should only sign intermediate certificates that match. +# See the POLICY FORMAT section of `man ca`. +countryName = match +stateOrProvinceName = match +organizationName = match +organizationalUnitName = optional +commonName = supplied +emailAddress = optional + +[ policy_loose ] +# Allow the intermediate CA to sign a more diverse range of certificates. +# See the POLICY FORMAT section of the `ca` man page. +countryName = optional +stateOrProvinceName = optional +localityName = optional +organizationName = optional +organizationalUnitName = optional +commonName = supplied +emailAddress = optional + +[ req ] +# Options for the `req` tool (`man req`). +default_bits = 2048 +distinguished_name = req_distinguished_name +string_mask = utf8only + +# SHA-1 is deprecated, so use SHA-2 instead. +default_md = sha256 + +# Extension to add when the -x509 option is used. +x509_extensions = v3_ca + +[ req_distinguished_name ] +# See . +countryName = Country Name (2 letter code) +stateOrProvinceName = State or Province Name +localityName = Locality Name +0.organizationName = Organization Name +organizationalUnitName = Organizational Unit Name +commonName = Common Name +emailAddress = Email Address + +# Optionally, specify some defaults. +countryName_default = GB +stateOrProvinceName_default = England +localityName_default = +0.organizationName_default = Alice Ltd +organizationalUnitName_default = +emailAddress_default = + +[ v3_ca ] +# Extensions for a typical CA (`man x509v3_config`). +subjectKeyIdentifier = hash +authorityKeyIdentifier = keyid:always,issuer +basicConstraints = critical, CA:true +keyUsage = critical, digitalSignature, cRLSign, keyCertSign + +[ v3_intermediate_ca ] +# Extensions for a typical intermediate CA (`man x509v3_config`). +subjectKeyIdentifier = hash +authorityKeyIdentifier = keyid:always,issuer +basicConstraints = critical, CA:true, pathlen:0 +keyUsage = critical, digitalSignature, cRLSign, keyCertSign + +[ usr_cert ] +# Extensions for client certificates (`man x509v3_config`). +basicConstraints = CA:FALSE +nsCertType = client, email +nsComment = "OpenSSL Generated Client Certificate" +subjectKeyIdentifier = hash +authorityKeyIdentifier = keyid,issuer +keyUsage = critical, nonRepudiation, digitalSignature, keyEncipherment +extendedKeyUsage = clientAuth, emailProtection + +[ server_cert ] +# Extensions for server certificates (`man x509v3_config`). +basicConstraints = CA:FALSE +nsCertType = server +nsComment = "OpenSSL Generated Server Certificate" +subjectKeyIdentifier = hash +authorityKeyIdentifier = keyid,issuer:always +keyUsage = critical, digitalSignature, keyEncipherment +extendedKeyUsage = serverAuth + +[ crl_ext ] +# Extension for CRLs (`man x509v3_config`). +authorityKeyIdentifier=keyid:always + +[ ocsp ] +# Extension for OCSP signing certificates (`man ocsp`). +basicConstraints = CA:FALSE +subjectKeyIdentifier = hash +authorityKeyIdentifier = keyid,issuer +keyUsage = critical, digitalSignature +extendedKeyUsage = critical, OCSPSigning +``` + +Create root certificate: + +```sh +openssl req -config openssl.cnf -key private/ca.key.pem -new -x509 -days 7300 -sha256 -extensions v3_ca -out certs/ca.cert.pem +``` + +## Create Certificate Signing Request +```sh +openssl req -new -newkey rsa:2048 -nodes -keyout server.key -out server.csr +``` + +## Create Certificate Chain +```sh +mkdir -p /root/intermediate +echo 1000 > /root/intermediate/serial +echo 0100 > /root/intermediate/crlnumber +``` + +Configure OpenSSL: +```sh +vi /root/intermediate/openssl_intermediate.cnf +``` + +***`openssl_intermediate.cnf`:*** +```ini +[ ca ] # The default CA section +default_ca = CA_default # The default CA name + +[ CA_default ] # Default settings for the intermediate CA +dir = /root/intermediate # Intermediate CA directory +certs = $dir/certs # Certificates directory +crl_dir = $dir/crl # CRL directory +new_certs_dir = $dir/newcerts # New certificates directory +database = $dir/index.txt # Certificate index file +serial = $dir/serial # Serial number file +RANDFILE = $dir/private/.rand # Random number file +private_key = $dir/private/intermediate.key.pem # Intermediate CA private key +certificate = $dir/certs/intermediate.cert.pem # Intermediate CA certificate +crl = $dir/crl/intermediate.crl.pem # Intermediate CA CRL +crlnumber = $dir/crlnumber # Intermediate CA CRL number +crl_extensions = crl_ext # CRL extensions +default_crl_days = 30 # Default CRL validity days +default_md = sha256 # Default message digest +preserve = no # Preserve existing extensions +email_in_dn = no # Exclude email from the DN +name_opt = ca_default # Formatting options for names +cert_opt = ca_default # Certificate output options +policy = policy_loose # Certificate policy + +[ policy_loose ] # Policy for less strict validation +countryName = optional # Country is optional +stateOrProvinceName = optional # State or province is optional +localityName = optional # Locality is optional +organizationName = optional # Organization is optional +organizationalUnitName = optional # Organizational unit is optional +commonName = supplied # Must provide a common name +emailAddress = optional # Email address is optional + +[ req ] # Request settings +default_bits = 2048 # Default key size +distinguished_name = req_distinguished_name # Default DN template +string_mask = utf8only # UTF-8 encoding +default_md = sha256 # Default message digest +x509_extensions = v3_intermediate_ca # Extensions for intermediate CA certificate + +[ req_distinguished_name ] # Template for the DN in the CSR +countryName = Country Name (2 letter code) +stateOrProvinceName = State or Province Name +localityName = Locality Name +0.organizationName = Organization Name +organizationalUnitName = Organizational Unit Name +commonName = Common Name +emailAddress = Email Address + +[ v3_intermediate_ca ] # Intermediate CA certificate extensions +subjectKeyIdentifier = hash # Subject key identifier +authorityKeyIdentifier = keyid:always,issuer # Authority key identifier +basicConstraints = critical, CA:true, pathlen:0 # Basic constraints for a CA +keyUsage = critical, digitalSignature, cRLSign, keyCertSign # Key usage for a CA + +[ crl_ext ] # CRL extensions +authorityKeyIdentifier=keyid:always # Authority key identifier + +[ server_cert ] # Server certificate extensions +basicConstraints = CA:FALSE # Not a CA certificate +nsCertType = server # Server certificate type +keyUsage = critical, digitalSignature, keyEncipherment # Key usage for a server cert +extendedKeyUsage = serverAuth # Extended key usage for server authentication purposes (e.g., TLS/SSL servers). +authorityKeyIdentifier = keyid,issuer # Authority key identifier linking the certificate to the issuer's public key. +``` + +```sh +openssl genrsa -out /root/intermediate/intermediate.key.pem 4096 +``` + +Requesting and signing intermediate certificate: + +```sh +cd /root/intermediate + +# Create Request +openssl req -new -newkey rsa:2048 -nodes -key intermediate.key.pem -out intermediate.req + +# Sign Certificate +openssl ca -config /root/ca/openssl.cnf -extensions v3_intermediate_ca -days 3650 -notext -md sha256 -in intermediate.req -out intermediate.cer +```