Add Check for empty parts to OpenXmlValidator

src/DocumentFormat.OpenXml.Framework/Packaging/OpenSettings.cs

@@ -74,5 +74,17 @@ public MarkupCompatibilityProcessSettings MarkupCompatibilityProcessSettings
         /// This property allows you to mitigate denial of service attacks where the attacker submits a package with an extremely large Open XML part. By limiting the size of the part, you can detect the attack and recover reliably.
         /// </remarks>
         public long MaxCharactersInPart { get; set; }
+
+        /// <summary>
+        /// Gets or sets a value indicating whether to validate that the document meets the minimum requirements for a valid package.
+        /// </summary>
+        /// <value>
+        /// <c>true</c> if the document should be validated for minimum requirements; otherwise, <c>false</c>.
+        /// </value>
+        /// <remarks>
+        /// When set to <c>true</c>, the document will be checked to ensure it contains the necessary parts and structure
+        /// to be considered a valid Open XML package.
+        /// </remarks>
+        public bool VerifyMinimumPackage { get; set; }
     }
 }

src/DocumentFormat.OpenXml.Framework/Packaging/OpenXmlPackage.cs

@@ -105,6 +105,18 @@ internal void LoadAllParts()
             }
         }
 
+        /// <summary>
+        /// Throws a <see cref="FileFormatException"/> if the current <see cref="OpenXmlPackage"/> does not meet the minimum requirements for a valid package.
+        /// </summary>
+        /// <exception cref="FileFormatException">
+        /// Thrown when the package does not conform to the minimum requirements for Office to open.
+        /// </exception>
+        /// <remarks>
+        /// This method is intended to be overridden by derived classes to implement specific validation logic
+        /// for different types of Open XML packages (e.g., Wordprocessing, Spreadsheet, or Presentation documents).
+        /// </remarks>
+        protected virtual void ThrowIfNotMinimumPackage() => throw new FileFormatException("The provided package does not conform to the minimum requirements for Office to open.");
+
         #region public methods
 
         /// <summary>

src/DocumentFormat.OpenXml.Framework/PublicAPI/PublicAPI.Shipped.txt

@@ -1009,3 +1009,5 @@ DocumentFormat.OpenXml.OpenXmlPartWriterSettings.Encoding.set -> void
 DocumentFormat.OpenXml.OpenXmlPartWriterSettings.OpenXmlPartWriterSettings() -> void
 DocumentFormat.OpenXml.OpenXmlPartWriter.OpenXmlPartWriter(DocumentFormat.OpenXml.Packaging.OpenXmlPart! openXmlPart, DocumentFormat.OpenXml.OpenXmlPartWriterSettings! settings) -> void
 DocumentFormat.OpenXml.OpenXmlPartWriter.OpenXmlPartWriter(System.IO.Stream! partStream, DocumentFormat.OpenXml.OpenXmlPartWriterSettings! settings) -> void
+DocumentFormat.OpenXml.Packaging.OpenSettings.VerifyMinimumPackage.get -> bool
+DocumentFormat.OpenXml.Packaging.OpenSettings.VerifyMinimumPackage.set -> void

src/DocumentFormat.OpenXml/Packaging/PresentationDocument.cs

@@ -3,6 +3,7 @@
 
 using DocumentFormat.OpenXml.Builder;
 using DocumentFormat.OpenXml.Features;
+using DocumentFormat.OpenXml.Presentation;
 using System;
 using System.Diagnostics.CodeAnalysis;
 using System.IO;
@@ -231,6 +232,13 @@ public static PresentationDocument Open(Package package)
         public static PresentationDocument Open(string path, bool isEditable, OpenSettings openSettings)
             => CreateDefaultBuilder()
                 .UseSettings(openSettings)
+                .Use(package =>
+                {
+                    if (openSettings.VerifyMinimumPackage)
+                    {
+                        package.ThrowIfNotMinimumPackage();
+                    }
+                })
                 .Build()
                 .Open(path, isEditable);
 
@@ -248,6 +256,13 @@ public static PresentationDocument Open(string path, bool isEditable, OpenSettin
         public static PresentationDocument Open(Stream stream, bool isEditable, OpenSettings openSettings)
             => CreateDefaultBuilder()
                 .UseSettings(openSettings)
+                .Use(package =>
+                {
+                    if (openSettings.VerifyMinimumPackage)
+                    {
+                        package.ThrowIfNotMinimumPackage();
+                    }
+                })
                 .Build()
                 .Open(stream, isEditable);
 
@@ -264,9 +279,58 @@ public static PresentationDocument Open(Stream stream, bool isEditable, OpenSett
         public static PresentationDocument Open(Package package, OpenSettings openSettings)
             => CreateDefaultBuilder()
                 .UseSettings(openSettings)
+                .Use(package =>
+                {
+                    if (openSettings.VerifyMinimumPackage)
+                    {
+                        package.ThrowIfNotMinimumPackage();
+                    }
+                })
                 .Build()
                 .Open(package);
 
+        /// <summary>
+        /// Validates that the current <see cref="PresentationDocument"/> meets the minimum requirements for a valid package.
+        /// </summary>
+        /// <exception cref="NotSupportedException">
+        /// Thrown if the <see cref="PresentationDocumentType"/> is <see cref="PresentationDocumentType.Slideshow"/>,
+        /// <see cref="PresentationDocumentType.MacroEnabledSlideshow"/>, or <see cref="PresentationDocumentType.AddIn"/>,
+        /// as validation for these types is not supported.
+        /// </exception>
+        /// <exception cref="FileFormatException">
+        /// Thrown if the <see cref="PresentationPart"/> does not contain valid <c>NotesSize</c> dimensions
+        /// or if the dimensions are outside the acceptable range for PowerPoint to open.
+        /// </exception>
+        /// <remarks>
+        /// This method ensures that the document conforms to the minimum requirements for PowerPoint to open it.
+        /// </remarks>
+        protected override void ThrowIfNotMinimumPackage()
+        {
+            if (this.DocumentType == PresentationDocumentType.Slideshow)
+            {
+                throw new NotSupportedException("Minimum package verification for PresentationDocumentType.Slideshow (.ppsx) is not supported.");
+            }
+
+            if (this.DocumentType == PresentationDocumentType.MacroEnabledSlideshow)
+            {
+                throw new NotSupportedException("Minimum package verification for PresentationDocumentType.MacroEnabledSlideshow (.ppsm) is not supported.");
+            }
+
+            if (this.DocumentType == PresentationDocumentType.AddIn)
+            {
+                throw new NotSupportedException("Minimum package verification for PresentationDocumentType.AddIn (.ppam) is not supported.");
+            }
+
+            NotesSize? notesSize = this.PresentationPart?.Presentation?.NotesSize;
+
+            if (!(notesSize is not null && notesSize.Cx is not null && notesSize.Cx.HasValue &&
+               notesSize.Cx >= 0 && notesSize.Cx <= 27273042316900 && notesSize.Cy is not null &&
+               notesSize.Cy.HasValue && notesSize.Cy >= 0 && notesSize.Cy <= 27273042316900))
+            {
+                throw new FileFormatException("The provided package does not conform to the minimum requirements for PowerPoint to open.");
+            }
+        }
+
         /// <summary>
         /// Changes the document type.
         /// </summary>

src/DocumentFormat.OpenXml/Packaging/SpreadsheetDocument.cs

@@ -3,6 +3,7 @@
 
 using DocumentFormat.OpenXml.Builder;
 using DocumentFormat.OpenXml.Features;
+using DocumentFormat.OpenXml.Spreadsheet;
 using System;
 using System.Diagnostics.CodeAnalysis;
 using System.IO;
@@ -197,6 +198,13 @@ public static SpreadsheetDocument CreateFromTemplate(string path)
         public static SpreadsheetDocument Open(string path, bool isEditable, OpenSettings openSettings)
             => CreateDefaultBuilder()
                 .UseSettings(openSettings)
+                .Use(package =>
+                {
+                    if (openSettings.VerifyMinimumPackage)
+                    {
+                        package.ThrowIfNotMinimumPackage();
+                    }
+                })
                 .Build()
                 .Open(path, isEditable);
 
@@ -214,6 +222,13 @@ public static SpreadsheetDocument Open(string path, bool isEditable, OpenSetting
         public static SpreadsheetDocument Open(Stream stream, bool isEditable, OpenSettings openSettings)
             => CreateDefaultBuilder()
                 .UseSettings(openSettings)
+                .Use(package =>
+                {
+                    if (openSettings.VerifyMinimumPackage)
+                    {
+                        package.ThrowIfNotMinimumPackage();
+                    }
+                })
                 .Build()
                 .Open(stream, isEditable);
 
@@ -230,6 +245,13 @@ public static SpreadsheetDocument Open(Stream stream, bool isEditable, OpenSetti
         public static SpreadsheetDocument Open(Package package, OpenSettings openSettings)
             => CreateDefaultBuilder()
                 .UseSettings(openSettings)
+                .Use(package =>
+                {
+                    if (openSettings.VerifyMinimumPackage)
+                    {
+                        package.ThrowIfNotMinimumPackage();
+                    }
+                })
                 .Build()
                 .Open(package);
 
@@ -267,6 +289,39 @@ public static SpreadsheetDocument Open(System.IO.Stream stream, bool isEditable)
         public static SpreadsheetDocument Open(System.IO.Packaging.Package package)
             => Open(package, new OpenSettings());
 
+        /// <summary>
+        /// Throws a <see cref="FileFormatException"/> if the current <see cref="SpreadsheetDocument"/>
+        /// does not meet the minimum requirements for a valid package.
+        /// </summary>
+        /// <exception cref="FileFormatException">
+        /// Thrown when the <see cref="SpreadsheetDocument"/> does not conform to the minimum requirements
+        /// for Excel to open. This includes:
+        /// <list type="bullet">
+        /// <item><description>The document type is <see cref="SpreadsheetDocumentType.AddIn"/>.</description></item>
+        /// <item><description>The <see cref="WorkbookPart"/> is missing or does not contain a valid <see cref="Sheet"/>.</description></item>
+        /// <item><description>The <see cref="SheetData"/> in the first <see cref="WorksheetPart"/> is missing.</description></item>
+        /// </list>
+        /// </exception>
+        /// <remarks>
+        /// This method ensures that the <see cref="SpreadsheetDocument"/> contains the necessary parts and structure
+        /// to be opened with Excel.
+        /// </remarks>
+        protected override void ThrowIfNotMinimumPackage()
+        {
+            if (this.DocumentType == SpreadsheetDocumentType.AddIn)
+            {
+                throw new NotSupportedException("Validation for SpreadsheetDocument.AddIn (.xlam) is not supported.");
+            }
+
+            Sheet? sheet = this.WorkbookPart?.Workbook?.Sheets?.GetFirstChild<Sheet>();
+            SheetData? sheetData = this.WorkbookPart?.WorksheetParts?.FirstOrDefaultAndMaxOne()?.Worksheet?.GetFirstChild<SheetData>();
+
+            if (sheet is null || sheetData is null)
+            {
+                throw new FileFormatException("The provided package does not conform to the minimum requirements for Excel to open.");
+            }
+        }
+
         /// <summary>
         /// Changes the document type.
         /// </summary>

src/DocumentFormat.OpenXml/Packaging/WordprocessingDocument.cs

@@ -264,6 +264,13 @@ public static WordprocessingDocument Open(Stream stream, bool isEditable)
         public static WordprocessingDocument Open(string path, bool isEditable, OpenSettings openSettings)
             => CreateDefaultBuilder()
                 .UseSettings(openSettings)
+                .Use(package =>
+                {
+                    if (openSettings.VerifyMinimumPackage)
+                    {
+                        package.ThrowIfNotMinimumPackage();
+                    }
+                })
                 .Build()
                 .Open(path, isEditable);
 
@@ -281,6 +288,13 @@ public static WordprocessingDocument Open(string path, bool isEditable, OpenSett
         public static WordprocessingDocument Open(Stream stream, bool isEditable, OpenSettings openSettings)
             => CreateDefaultBuilder()
                 .UseSettings(openSettings)
+                .Use(package =>
+                {
+                    if (openSettings.VerifyMinimumPackage)
+                    {
+                        package.ThrowIfNotMinimumPackage();
+                    }
+                })
                 .Build()
                 .Open(stream, isEditable);
 
@@ -297,6 +311,13 @@ public static WordprocessingDocument Open(Stream stream, bool isEditable, OpenSe
         public static WordprocessingDocument Open(Package package, OpenSettings openSettings)
             => CreateDefaultBuilder()
                 .UseSettings(openSettings)
+                .Use(package =>
+                {
+                    if (openSettings.VerifyMinimumPackage)
+                    {
+                        package.ThrowIfNotMinimumPackage();
+                    }
+                })
                 .Build()
                 .Open(package);
 
@@ -311,6 +332,24 @@ public static WordprocessingDocument Open(Package package, OpenSettings openSett
         public static WordprocessingDocument Open(Package package)
             => Open(package, new OpenSettings());
 
+        /// <summary>
+        /// Throws a <see cref="FileFormatException"/> if the current <see cref="WordprocessingDocument"/> does not meet the minimum requirements for a valid package.
+        /// </summary>
+        /// <exception cref="FileFormatException">
+        /// Thrown when the <see cref="MainDocumentPart"/> is missing or its <see cref="Document.Body"/> is null.
+        /// </exception>
+        /// <remarks>
+        /// This method ensures that the <see cref="WordprocessingDocument"/> contains the necessary parts and structure
+        /// to be opened with Word.
+        /// </remarks>
+        protected override void ThrowIfNotMinimumPackage()
+        {
+            if (this.MainDocumentPart?.Document?.Body is null)
+            {
+                throw new FileFormatException("The provided package does not conform to the minimum requirements for Word to open.");
+            }
+        }
+
         /// <summary>
         /// Changes the document type.
         /// </summary>