Adding possibility to set SAN when using New-PnPAzureCertificate (#3555)

* Adding possibility to set the Subject Alternative Names on the self signed certificate

* Adding changelog entry

---------

Co-authored-by: Gautam Sheth <gautamdsheth@outlook.com>

Author: KoenZomers

CHANGELOG.md

@@ -41,6 +41,7 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/).
 - Added `-RelativeUrl` parameter to `Connect-PnPOnline` cmdlet to allow specifying custom URLs for usage with `-WebLogin` method. [#3530](https://github.com/pnp/powershell/pull/3530)
 - Added `-RetryCount` to `Submit-PnPSearchQuery` which allows for specifying the number of retries to perform when an exception occurs [#3528](https://github.com/pnp/powershell/pull/3528)
 - Added `-MailNickname` parameter to `Set-PnPMicrosoft365Group` cmdlet to allow changing of this property on a Microsoft 365 Group [#3529](https://github.com/pnp/powershell/pull/3529)
+- Added `-SanNames` to `New-PnPAzureCertificate` which allows for controlling the Subject Alternative Names set on the generated certificate [#3555](https://github.com/pnp/powershell/pull/3555)
 - Added Information Barriers information to the output of `Get-PnPTenantSite` [#3556](https://github.com/pnp/powershell/pull/3556)
 - Added `RequestFilesLinkEnabled` and `RequestFilesLinkExpirationInDays` to the output of `Get-PnPSite` [#3557](https://github.com/pnp/powershell/pull/3557)
 - Added `CoreRequestFilesLinkEnabled`, `CoreRequestFilesLinkExpirationInDays`, `OneDriveRequestFilesLinkEnabled`, `OneDriveRequestFilesLinkExpirationInDays`, `BusinessConnectivityServiceDisabled` to the output of `Get-PnPTenant` [#3557](https://github.com/pnp/powershell/pull/3557)

documentation/New-PnPAzureCertificate.md

@@ -25,12 +25,12 @@ PrivateKey contains the PEM encoded private key of the certificate.
 ```powershell
 New-PnPAzureCertificate [-CommonName <String>] [-Country <String>] [-State <String>]
  [-Locality <String>] [-Organization <String>] [-OrganizationUnit <String>] [-OutPfx <String>]
- [-OutCert <String>] [-ValidYears <Int32>] [-CertificatePassword <SecureString>] [-Store <StoreLocation>] 
+ [-OutCert <String>] [-ValidYears <Int32>] [-CertificatePassword <SecureString>] [-Store <StoreLocation>] [-SanNames <String[]>]
 ```
 
 ## DESCRIPTION
 
-Allows to create a self-signed certificate and manifest settings to be used with CSOM via an app-only ADAL application.
+Allows to create a self-signed certificate and manifest settings to be used with PnP PowerShell via an app-only application registration.
 
 ## EXAMPLES
 
@@ -39,21 +39,28 @@ Allows to create a self-signed certificate and manifest settings to be used with
 New-PnPAzureCertificate -OutPfx pnp.pfx -OutCert pnp.cer
 ```
 
-This will generate a default self-signed certificate named "pnp.contoso.com" valid for 10 years and output a pfx and cer file to disk. The private key file (pfx) will not be password protected.
+This will generate a default self-signed certificate named "pnp.contoso.com" valid for 10 years and output a pfx and cer file to disk. The private key file (pfx) will not be password protected. It will have localhost and the machinename as the Subject Alternative Names.
 
 ### EXAMPLE 2
 ```powershell
 New-PnPAzureCertificate -CommonName "My Certificate" -ValidYears 30
 ```
 
-This will output a certificate named "My Certificate" which expires in 30 years from now to the screen. It will not write the certificate files to disk.
+This will output a certificate named "My Certificate" which expires in 30 years from now to the screen. It will not write the certificate files to disk. It will have localhost and the machinename as the Subject Alternative Names.
 
 ### EXAMPLE 3
 ```powershell
 New-PnPAzureCertificate -OutPfx pnp.pfx -OutCert pnp.cer -CertificatePassword (ConvertTo-SecureString -String "pass@word1" -AsPlainText -Force)
 ```
 
-This will generate a default self-signed certificate named "pnp.contoso.com" valid for 10 years and output a pfx and cer file to disk. The pfx file will have the password pass@word1 set on it.
+This will generate a default self-signed certificate named "pnp.contoso.com" valid for 10 years and output a pfx and cer file to disk. The pfx file will have the password pass@word1 set on it. It will have localhost and the machinename as the Subject Alternative Names.
+
+### EXAMPLE 4
+```powershell
+New-PnPAzureCertificate -OutPfx pnp.pfx -OutCert pnp.cer -SanNames $null
+```
+
+This will generate a default self-signed certificate named "pnp.contoso.com" valid for 10 years and output a pfx and cer file to disk. There will not be any Subject Alternative Names in the generated certificate.
 
 ## PARAMETERS
 
@@ -169,6 +176,24 @@ Accept pipeline input: False
 Accept wildcard characters: False
 ```
 
+### -SanNames
+One or more DNS names to add to the certificate as Subject Alternative Names. Separate multiple names with a comma, i.e. "host1.domain.com","host2.domain.com".
+
+Provide $null to not add any Subject Alternative names to the certificate.
+
+Omit to add localhost and the machine name as Subject Alternative Names.
+
+```yaml
+Type: String[]
+Parameter Sets: (All)
+
+Required: False
+Position: Named
+Default value: None
+Accept pipeline input: False
+Accept wildcard characters: False
+```
+
 ### -State
 State or Province Name (full name)
 

src/Commands/AzureAD/RegisterAzureADApp.cs

@@ -493,7 +493,7 @@ private X509Certificate2 GetCertificate(PSObject record)
                 }
                 DateTime validFrom = DateTime.Today;
                 DateTime validTo = validFrom.AddYears(ValidYears);
-                cert = CertificateHelper.CreateSelfSignedCertificate(CommonName, Country, State, Locality, Organization, OrganizationUnit, CertificatePassword, CommonName, validFrom, validTo);
+                cert = CertificateHelper.CreateSelfSignedCertificate(CommonName, Country, State, Locality, Organization, OrganizationUnit, CertificatePassword, CommonName, validFrom, validTo, Array.Empty<string>());
 
                 if (Directory.Exists(OutPath))
                 {

src/Commands/Base/GetAzureCertificate.cs

@@ -3,6 +3,9 @@
 using System.Security;
 using System.Security.Cryptography.X509Certificates;
 using PnP.PowerShell.Commands.Utilities;
+using System.Runtime.ConstrainedExecution;
+using System.Security.Cryptography;
+using System.Linq;
 
 namespace PnP.PowerShell.Commands.Base
 {
@@ -84,7 +87,12 @@ internal static void WriteAzureCertificateOutput(PSCmdlet cmdlet, X509Certificat
                 pfxBase64: pfxBase64,
                 keyCredentials: manifestEntry,
                 certificate: CertificateHelper.CertificateToBase64(certificate),
-                privateKey: CertificateHelper.PrivateKeyToBase64(certificate)
+                privateKey: CertificateHelper.PrivateKeyToBase64(certificate),
+                sanNames: certificate.Extensions.Cast<X509Extension>()
+                                                .Where(n => n.Oid.FriendlyName=="Subject Alternative Name")
+                                                .Select(n => new AsnEncodedData(n.Oid, n.RawData))
+                                                .Select(n => n.Format(false))
+                                                .FirstOrDefault().Split(',', StringSplitOptions.TrimEntries)
             );
 
             cmdlet.WriteObject(record);

src/Commands/Base/NewAzureCertificate.cs

@@ -46,6 +46,9 @@ public class NewPnPAdalCertificate : PSCmdlet
         [Parameter(Mandatory = false)]
         public StoreLocation Store;
 
+        [Parameter(Mandatory = false)]
+        public string[] SanNames;
+
         protected override void ProcessRecord()
         {
             if (MyInvocation.BoundParameters.ContainsKey(nameof(Store)) && !Utilities.OperatingSystem.IsWindows())
@@ -60,7 +63,12 @@ protected override void ProcessRecord()
             DateTime validFrom = DateTime.Today;
             DateTime validTo = validFrom.AddYears(ValidYears);
 
-            X509Certificate2 certificate = CertificateHelper.CreateSelfSignedCertificate(CommonName, Country, State, Locality, Organization, OrganizationUnit, CertificatePassword, CommonName, validFrom, validTo);
+            if(MyInvocation.BoundParameters.ContainsKey(nameof(SanNames)) && SanNames == null)
+            {
+                SanNames = Array.Empty<string>();
+            }
+
+            X509Certificate2 certificate = CertificateHelper.CreateSelfSignedCertificate(CommonName, Country, State, Locality, Organization, OrganizationUnit, CertificatePassword, CommonName, validFrom, validTo, SanNames);
 
             if (!string.IsNullOrWhiteSpace(OutPfx))
             {

src/Commands/Model/AzureCertificate.cs

@@ -1,15 +1,10 @@
-using PnP.PowerShell.Commands.Utilities;
-
-using System;
-using System.Collections.Generic;
-using System.Security.Cryptography.X509Certificates;
-using System.Text;
+using System;
 
 namespace PnP.PowerShell.Commands.Model
 {
     public sealed class AzureCertificate
     {
-        internal AzureCertificate(string subject, DateTime notBefore, DateTime notAfter, string thumbprint, string/*?*/ pfxBase64, string keyCredentials, string certificate, string privateKey)
+        internal AzureCertificate(string subject, DateTime notBefore, DateTime notAfter, string thumbprint, string/*?*/ pfxBase64, string keyCredentials, string certificate, string privateKey, string[] sanNames)
         {
             Subject = subject ?? throw new ArgumentNullException(nameof(subject));
             NotBefore = notBefore;
@@ -19,6 +14,7 @@ internal AzureCertificate(string subject, DateTime notBefore, DateTime notAfter,
             KeyCredentials = keyCredentials ?? throw new ArgumentNullException(nameof(keyCredentials));
             Certificate = certificate ?? throw new ArgumentNullException(nameof(certificate));
             PrivateKey = privateKey ?? throw new ArgumentNullException(nameof(privateKey));
+            SanNames = sanNames;
         }
 
         public string Subject { get; }
@@ -29,6 +25,6 @@ internal AzureCertificate(string subject, DateTime notBefore, DateTime notAfter,
         public string KeyCredentials { get; }
         public string Certificate { get; }
         public string PrivateKey { get; }
-
+        public string[] SanNames { get; }
     }
 }

src/Commands/Utilities/CertificateHelper.cs

@@ -241,11 +241,21 @@ private static IEnumerable<string> SplitText(string text, int length)
 
         #endregion
 
-        internal static X509Certificate2 CreateSelfSignedCertificate(string commonName, string country, string state, string locality, string organization, string organizationUnit, SecureString password, string friendlyName, DateTimeOffset from, DateTimeOffset to)
+        internal static X509Certificate2 CreateSelfSignedCertificate(string commonName, string country, string state, string locality, string organization, string organizationUnit, SecureString password, string friendlyName, DateTimeOffset from, DateTimeOffset to, string[] sanNames = null)
         {
             SubjectAlternativeNameBuilder sanBuilder = new SubjectAlternativeNameBuilder();
-            sanBuilder.AddDnsName("localhost");
-            sanBuilder.AddDnsName(Environment.MachineName);
+            if (sanNames != null)
+            {
+                foreach (var sanName in sanNames)
+                {
+                    sanBuilder.AddDnsName(sanName);
+                }
+            }
+            else
+            {
+                sanBuilder.AddDnsName("localhost");
+                sanBuilder.AddDnsName(Environment.MachineName);
+            }
 
             var x500Values = new List<string>();
             if (!string.IsNullOrWhiteSpace(commonName)) x500Values.Add($"CN={commonName}");