wolfSSL CertManager Examples

February 3, 2026 ยท View on GitHub

This directory contains examples of using the wolfSSL CertManager to verify certificates in a standalone manner, separate from an SSL/TLS connection.

Example Applications

  • certverify.c - Basic certificate verification example
  • certloadverifybuffer.c - Certificate verification from memory buffer
  • certverify_ocsp.c - Certificate verification with OCSP revocation checking

certverify.c and/or certloadverifybuffer.c

Building wolfSSL

cd wolfssl
./autogen.sh
./configure
make all
make check
sudo make install

Building the Examples

cd wolfssl-examples/certmanager
make certverify
make certloadverifybuffer

Running the Examples

./certverify
./certloadverifybuffer

certverify_ocsp

The certverify_ocsp example demonstrates certificate verification with OCSP (Online Certificate Status Protocol) checking. These instructions assume that your wolfssl source directory and the wolfssl-examples directory share the same parent directory.

Building wolfSSL

cd wolfssl
./autogen.sh
./configure --enable-crl --enable-ocsp
make all
make check
sudo make install

Building the Example

cd wolfssl-examples/certmanager
make certverify_ocsp

Running the Example

The OCSP demo requires an OCSP responder to be running. You can start one using OpenSSL:

Terminal 1 - Start the OCSP Responder:

From the wolfssl-examples/certmanager directory:

openssl ocsp -port 22221 -ndays 365 \
    -index ../../wolfssl/certs/ocsp/index-intermediate1-ca-issued-certs.txt \
    -rsigner ../../wolfssl/certs/ocsp/ocsp-responder-cert.pem \
    -rkey ../../wolfssl/certs/ocsp/ocsp-responder-key.pem \
    -CA ../../wolfssl/certs/ocsp/intermediate1-ca-cert.pem \
    -text

Terminal 2 - Run the Example:

From the wolfssl-examples/certmanager directory:

./certverify_crl_ocsp

Expected Output

When the OCSP responder is running, you should see output that indicates basic verification passed and OCSP checking is done and successful. Importantly, OpenSSL should also show some pretty prints of the OCSP request.

OCSP Certificate Structure

The OCSP test uses the following certificate chain from the wolfSSL repository's certs/ocsp/ directory. This assumes the wolfssl and wolfssl-examples repositories are in the same parent directory.

  • root-ca-cert.pem - Root CA certificate
  • intermediate1-ca-cert.pem - Intermediate CA that issued the server cert
  • server1-cert.pem - Server certificate with OCSP URL in AIA extension
  • ocsp-responder-cert.pem - Certificate for the OCSP responder
  • ocsp-responder-key.pem - Private key for the OCSP responder

The server1-cert.pem certificate contains an Authority Information Access (AIA) extension pointing to http://127.0.0.1:22221 for OCSP queries.