Custom Certificates

1. What's it?
Proxyman supports Custom Root Certificate, Server Certificates, and Client Certificates that allow you to add your certificate that Proxyman uses to establish the SSL-Connection between your clients, servers, and Proxyman app.
Custom Certificate Type
Purpose
How Proxyman uses
Server Certificate
For intercepting HTTPS Traffic from clients that use SSL-Pinning
Use this certificate for SSL-Handshake to your Clients
Client Certificate
For intercepting HTTPS Traffic from clients that use Mutual Authentication
Use this certificate for SSL-Handshake to specific Server
Root Certificate
For intercepting HTTPS Traffic from clients and servers without using local Proxyman certificates
SSL Handshake for both clients & servers
Even though the Proxyman Root Certificate is locally generated in your machine, you can manually generate and add to Proxyman. Read more​
2. Certificate Formats
Proxyman accepts the following formats:
Custom Certificate
PEM or DER
PKCS #12 (p12)
Root Certificate
Not Supported
Supported
Client Certificate 
Supported
Supported
Server Certificate
Supported
Supported
PKCS #12 (p12).
PEM or DER Private Key and Certificate file.
Proxyman automatically determines the format of the Private Key and Certificate file (Support PEM or DER).
Proxyman will prompt to enter the password if import an encrypted Private Key or PKCS #12 file.
All passphrases are securely stored in Proxyman Keychain.
If your certificates are in different formats that Proxyman supports, please convert them to p12 or PEM/DER format before importing.
3. Certificate Requirement on macOS 10.15+ and iOS 13+
If you're using a custom Root Certificate or Server Certificate on macOS 10.15 or iOS 13, you might encounter the failed handshake on Safari or iOS devices if the following requirements don't meet:
RSA Key must have a key size is greater than 2048 bits
The hash algorithm is SHA-2 family
DNS Name of the server must be present on Subject Alternative Name. Common Name is no longer trusted
Valid certificate (Current day is in Not Before and Not After)
TLS server certificates must contain an ExtendedKeyUsage (EKU) extension containing the id-kp-serverAuth OID.
Read more https://support.apple.com/en-us/HT210176​
If it's too complicated for you, we recommend letting Proxyman performs it automatically. Please visit Certificate Menu -> Install Certificate on this Mac -> Select Automatic Tab.
4. Common issues
Problem
Solution
Private Key and Certificate are not matched
Try different certificates and private keys and make sure they are matched
Get SSL Handshake Error for custom certificates
Try to add the custom Certificate to System Keychain and Trust it
Certificate doesn't match the requirement from macOS => Read section 3​
Check expires day of the Certificate
Could not import certificate due to invalid passphrase
Ask your leader to give the correct passphrase to open the encrypted Private Key or P12 file
5. How to use
Access from Certificate Menu -> Add Custom Certificate
6. How to generate self-signed certificates for Custom Root Certificate that comply with new Apple's Security Requirements
Due to Apple's requirements from iOS 13 and Catalina (10.15), It requires extra configuration to generate the self-signed certificate properly.
The following steps will guide you on how to do it properly:
1.Prepare cert.config file on Desktop folder
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[ ca ]
2
default_ca    = CA_default
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[ CA_default ]
4
default_md    = sha256
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[ v3_ca ]
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subjectKeyIdentifier=hash
7
authorityKeyIdentifier=keyid:always,issuer
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basicConstraints = critical,CA:true
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keyUsage=critical,keyCertSign
10
extendedKeyUsage = serverAuth,clientAuth
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[ req ]
12
prompt = no
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distinguished_name    = req_distinguished_name
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[ req_distinguished_name ]
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C=SG
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L=SG
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O=Proxyman
18
CN=proxyman.dev
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OU=Proxyman
Copied!
Please update values for C, L, O, CN, and OU param.
2. Generate RSA Key in the Terminal app. (Make sure you replace your_password with your real password)
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cd ~/Desktop
2
openssl genrsa -aes256 -passout pass:your_password -out key.pem 2048
Copied!
 3. Generate the self-signed certificate and private key. (Make sure you replace your_password with your real password)
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openssl req -x509 -new -nodes -passin pass:your_password -config cert.config -key key.pem -sha256 -extensions v3_ca -days 825 -out root-ca.pem
Copied!
4. Convert to p12 format. (Make sure you replace your_password with your real password)
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openssl pkcs12 -export -out root-ca.p12 -in root-ca.pem -inkey key.pem -passin pass:your_password -passout pass:your_password
Copied!
5. Finally, you would have root-ca.p12 file and move to the next step
7. Import as a Custom Root Certificate
1.Go to Certificate Menu -> Custom Certificate -> Select Root Certificate Tab
2.Click Import button -> P12
3.Select root-ca.p12 file and enter the password.
4.Trust your custom certificate in Keychain Access App:
Open Keychain Access App
Search for the certificate you've added. The name might be the common name (CN) of the certificate
Double Click to open and select Always Trust
Click "X" and save the change
5. Please verify that you can see the Green Tick that shows the certificate is installed and trusted properly.
Custom Root Certificate is installed and trusted properly. Ready to go!
8. Import as a Server/Client Certificate
For custom Server/Client certificates, you should not generate a self-signed certificate. Please ask your workmate or team lead about the certificate that the company is using. It could be in DER/PEM or P12 format.
Then import the certificate as a Server / Client Certificate in Custom Certificate Window.
Import PEM/DER key and private key to Custom Client/Server Certificate
You don't need to trust the certificate on System Keychain since it's not a Root Certificate.