certview

An Oh My Zsh plugin for fast inspection and verification of X.509 certificates, CSRs, and cryptographic keys (RSA, ECC, Ed25519) in both PEM and DER formats.

Features

• Automatic Format Detection: Handles ASCII PEM and binary DER files automatically.
• Three Dedicated Tools:
  • certview: Inspect X.509 certificates, check expiry, view SANs, serial numbers, fingerprints, and subjects.
  • csrview: Inspect Certificate Signing Requests and verify CSR cryptographic signatures.
  • keyview: Inspect RSA, ECDSA (ECC curves), and Ed25519 private/public keys, test integrity, or export public keys.
• Zsh Tab-Completion: Built-in completions for flags and certificate/key file extensions (.pem, .der, .crt, .key, .csr, etc.).

---

Installation

Oh My Zsh

Clone the repository into your custom plugins directory:

git clone https://github.com/jnnrgd/certview.git ${ZSH_CUSTOM:-$HOME/.oh-my-zsh/custom}/plugins/certview

Add certview to your plugins list in ~/.zshrc:

plugins=(
  git
  certview
)

Reload your environment:

source ~/.zshrc

---

Usage

1. certview (X.509 Certificates)

# View full certificate details
certview cert.pem

# Extract specific fields
certview -s cert.crt              # Subject DN
certview -i cert.crt              # Issuer DN
certview -d cert.der              # NotBefore & NotAfter validity dates
certview -f cert.pem              # SHA-256 fingerprint
certview -n cert.crt              # Subject Alternative Names (SANs)
certview --serial cert.crt        # Serial number
certview -m cert.crt              # Key modulus

# Combine multiple flags
certview -s -i -d cert.pem

# Quick validity / expiration check (pass/fail)
certview -c cert.crt

2. csrview (Certificate Signing Requests)

# View full decoded CSR
csrview request.csr

# Extract specific fields
csrview -s request.csr            # Subject DN
csrview -n request.csr            # Requested Subject Alternative Names (SANs)
csrview -p request.csr            # Public key
csrview -m request.csr            # Key modulus (RSA)

# Cryptographically verify self-signature on CSR
csrview -v request.csr

3. keyview (Keys: RSA, ECC, Ed25519)

# View key parameters & curves (prime256v1, secp384r1, RSA bit length)
keyview private.key
keyview ec.der

# Verify key integrity
keyview -c id_rsa

# Extract and output public key in PEM format
keyview -p private.key > public.pub

---

License

This project is dedicated to the public domain under the Creative Commons Zero v1.0 Universal (CC0 1.0). You can copy, modify, distribute, and perform the work, even for commercial purposes, all without asking permission.