chore: Add HTTPs restriction for URLs on Attachments, ApiActions, GuiActions

src/Digdir.Domain.Dialogporten.Application/Common/Extensions/FluentValidation/FluentValidationStringExtensions.cs

@@ -1,13 +1,91 @@
 using FluentValidation;
+using HtmlAgilityPack;
 
 namespace Digdir.Domain.Dialogporten.Application.Common.Extensions.FluentValidation;
 
 internal static class FluentValidationStringExtensions
 {
+    private static readonly string[] AllowedTags = ["p", "a", "br", "em", "strong", "ul", "ol", "li"];
+    private static readonly string ContainsValidHtmlError =
+        "Value contains unsupported HTML. The following tags are supported: " +
+        $"[{string.Join(",", AllowedTags.Select(x => '<' + x + '>'))}]. Tag attributes " +
+        "are not supported except for on '<a>' which must contain a 'href' starting " +
+        "with 'https://'.";
+
     public static IRuleBuilderOptions<T, string?> IsValidUri<T>(this IRuleBuilder<T, string?> ruleBuilder)
     {
         return ruleBuilder
             .Must(uri => uri is null || Uri.IsWellFormedUriString(uri, UriKind.RelativeOrAbsolute))
-            .WithMessage("'{PropertyName}' is not a well formatted URI.");
+            .WithMessage("'{PropertyName}' is not a well-formatted URI.");
+    }
+
+    public static IRuleBuilderOptions<T, string?> IsValidHttpsUrl<T>(this IRuleBuilder<T, string?> ruleBuilder)
+    {
+        return ruleBuilder
+            .Must(x => x is null || (Uri.TryCreate(x, UriKind.Absolute, out var uri) && uri.Scheme == Uri.UriSchemeHttps))
+            .WithMessage("'{PropertyName}' is not a well-formatted HTTPS URL.");
+    }
+
+    public static IRuleBuilderOptions<T, Uri?> IsValidHttpsUrl<T>(this IRuleBuilder<T, Uri?> ruleBuilder)
+    {
+        return ruleBuilder
+            .Must(x => x is null || (x.IsAbsoluteUri && x.Scheme == Uri.UriSchemeHttps))
+            .WithMessage("'{PropertyName}' is not a well-formatted HTTPS URL.");
+    }
+
+    public static IRuleBuilderOptions<T, string?> ContainsValidHtml<T>(
+        this IRuleBuilder<T, string?> ruleBuilder)
+    {
+        return ruleBuilder
+            .Must(x => x is null || x.HtmlAgilityPackCheck())
+            .WithMessage(ContainsValidHtmlError);
+    }
+
+    private static bool HtmlAgilityPackCheck(this string html)
+    {
+        var doc = new HtmlDocument();
+        doc.LoadHtml(html);
+        var nodes = doc.DocumentNode.DescendantsAndSelf();
+        foreach (var node in nodes)
+        {
+            if (node.NodeType != HtmlNodeType.Element) continue;
+
+            if (!AllowedTags.Contains(node.Name))
+            {
+                return false;
+            }
+            // If the node is a hyperlink, it should only have a href attribute,
+            // and it must start with 'https://'
+            if (node.IsAnchorTag())
+            {
+                if (!node.IsValidAnchorTag())
+                {
+                    return false;
+                }
+
+                continue;
+            }
+
+            if (node.Attributes.Count > 0)
+            {
+                return false;
+            }
+        }
+        return true;
+    }
+
+    private static bool IsAnchorTag(this HtmlNode node)
+    {
+        const string anchorTag = "a";
+        return node.Name == anchorTag;
+    }
+
+    private static bool IsValidAnchorTag(this HtmlNode node)
+    {
+        const string https = "https://";
+        const string href = "href";
+        return node.Attributes.Count == 1 &&
+            node.Attributes[href] is not null &&
+            node.Attributes[href].Value.StartsWith(https, StringComparison.InvariantCultureIgnoreCase);
     }
 }

src/Digdir.Domain.Dialogporten.Application/Digdir.Domain.Dialogporten.Application.csproj

@@ -9,7 +9,6 @@
     <ItemGroup>
         <PackageReference Include="AutoMapper" Version="13.0.1"/>
         <PackageReference Include="HtmlAgilityPack" Version="1.11.66"/>
-        <PackageReference Include="Markdig.Signed" Version="0.37.0"/>
         <PackageReference Include="Microsoft.Extensions.Hosting" Version="8.0.0"/>
         <PackageReference Include="Microsoft.Extensions.Options.ConfigurationExtensions" Version="8.0.0"/>
         <PackageReference Include="FluentValidation.DependencyInjectionExtensions" Version="11.10.0"/>

src/Digdir.Domain.Dialogporten.Application/Features/V1/Common/Content/ContentValueDtoValidator.cs

@@ -15,6 +15,19 @@ namespace Digdir.Domain.Dialogporten.Application.Features.V1.Common.Content;
 // The validator is manually created in the Create and Update validators
 internal interface IIgnoreOnAssemblyScan;
 
+// internal sealed class ContentFoo : AbstractValidator<LocalizationDto>
+// {
+//     public ContentFoo()
+//     {
+//
+//         RuleFor(x => x.Value)
+//             .IsValidHttpsUrl()
+//             // .Must(x => Uri.TryCreate(x.Value, UriKind.Absolute, out var uri) && uri.Scheme == Uri.UriSchemeHttps)
+//             // .IsValidHttpsUrl()
+//             .When((x, y) => x.MediaType is not null && x.MediaType.StartsWith(MediaTypes.EmbeddablePrefix, StringComparison.InvariantCultureIgnoreCase))
+//             // .WithMessage("{PropertyName} must be a valid HTTPS URL for embeddable content types");
+//     }
+// }
 internal sealed class ContentValueDtoValidator : AbstractValidator<ContentValueDto>, IIgnoreOnAssemblyScan
 {
     private const string LegacyHtmlMediaType = "text/html";
@@ -27,13 +40,17 @@ public ContentValueDtoValidator(DialogTransmissionContentType contentType)
             .WithMessage($"{{PropertyName}} '{{PropertyValue}}' is not allowed for content type {contentType.Name}. " +
                          $"Allowed media types are {string.Join(", ", contentType.AllowedMediaTypes.Select(x => $"'{x}'"))}");
 
-        RuleForEach(x => x.Value)
-            .ContainsValidMarkdown()
-            .When(x => x.MediaType is MediaTypes.Markdown);
-        RuleForEach(x => x.Value)
-            .Must(x => Uri.TryCreate(x.Value, UriKind.Absolute, out var uri) && uri.Scheme == Uri.UriSchemeHttps)
-            .When(x => x.MediaType is not null && x.MediaType.StartsWith(MediaTypes.EmbeddablePrefix, StringComparison.InvariantCultureIgnoreCase))
-            .WithMessage("{PropertyName} must be a valid HTTPS URL for embeddable content types");
+        When(x =>
+            x.MediaType is not null
+            && x.MediaType.StartsWith(MediaTypes.EmbeddablePrefix, StringComparison.InvariantCultureIgnoreCase),
+            () =>
+            {
+                RuleForEach(x => x.Value)
+                    .ChildRules(x => x
+                        .RuleFor(x => x.Value)
+                        .IsValidHttpsUrl());
+            });
+
         RuleFor(x => x.Value)
             .NotEmpty()
             .SetValidator(_ => new LocalizationDtosValidator(contentType.MaxLength));
@@ -47,16 +64,18 @@ public ContentValueDtoValidator(DialogContentType contentType, IUser? user = nul
             .Must(value => value is not null && allowedMediaTypes.Contains(value))
             .WithMessage($"{{PropertyName}} '{{PropertyValue}}' is not allowed for content type {contentType.Name}. " +
                          $"Allowed media types are {string.Join(", ", allowedMediaTypes.Select(x => $"'{x}'"))}");
-        RuleForEach(x => x.Value)
-            .ContainsValidHtml()
-            .When(x => string.Equals(x.MediaType, LegacyHtmlMediaType, StringComparison.OrdinalIgnoreCase));
-        RuleForEach(x => x.Value)
-            .ContainsValidMarkdown()
-            .When(x => x.MediaType is MediaTypes.Markdown);
-        RuleForEach(x => x.Value)
-            .Must(x => Uri.TryCreate(x.Value, UriKind.Absolute, out var uri) && uri.Scheme == Uri.UriSchemeHttps)
-            .When(x => x.MediaType is not null && x.MediaType.StartsWith(MediaTypes.EmbeddablePrefix, StringComparison.InvariantCultureIgnoreCase))
-            .WithMessage("{PropertyName} must be a valid HTTPS URL for embeddable content types");
+
+        When(x =>
+                x.MediaType is not null
+                && x.MediaType.StartsWith(MediaTypes.EmbeddablePrefix, StringComparison.InvariantCultureIgnoreCase),
+            () =>
+            {
+                RuleForEach(x => x.Value)
+                    .ChildRules(x => x
+                        .RuleFor(x => x.Value)
+                        .IsValidHttpsUrl());
+            });
+
         RuleFor(x => x.Value)
             .NotEmpty()
             .SetValidator(_ => new LocalizationDtosValidator(contentType.MaxLength));

src/Digdir.Domain.Dialogporten.Application/Features/V1/ServiceOwner/Dialogs/Commands/Create/CreateDialogCommandValidator.cs

@@ -264,7 +264,7 @@ public CreateDialogDialogAttachmentUrlDtoValidator()
     {
         RuleFor(x => x.Url)
             .NotNull()
-            .IsValidUri()
+            .IsValidHttpsUrl()
             .MaximumLength(Constants.DefaultMaxUriLength);
         RuleFor(x => x.ConsumerType)
             .IsInEnum();
@@ -291,7 +291,7 @@ public CreateDialogTransmissionAttachmentUrlDtoValidator()
     {
         RuleFor(x => x.Url)
             .NotNull()
-            .IsValidUri()
+            .IsValidHttpsUrl()
             .MaximumLength(Constants.DefaultMaxUriLength);
         RuleFor(x => x.ConsumerType)
             .IsInEnum();
@@ -318,7 +318,7 @@ public CreateDialogDialogGuiActionDtoValidator(
             .MaximumLength(Constants.DefaultMaxStringLength);
         RuleFor(x => x.Url)
             .NotNull()
-            .IsValidUri()
+            .IsValidHttpsUrl()
             .MaximumLength(Constants.DefaultMaxUriLength);
         RuleFor(x => x.AuthorizationAttribute)
             .MaximumLength(Constants.DefaultMaxStringLength);
@@ -361,7 +361,7 @@ public CreateDialogDialogApiActionEndpointDtoValidator()
             .MaximumLength(Constants.DefaultMaxStringLength);
         RuleFor(x => x.Url)
             .NotNull()
-            .IsValidUri()
+            .IsValidHttpsUrl()
             .MaximumLength(Constants.DefaultMaxUriLength);
         RuleFor(x => x.HttpMethod)
             .IsInEnum();

src/Digdir.Domain.Dialogporten.Application/Features/V1/ServiceOwner/Dialogs/Commands/Update/UpdateDialogCommandValidator.cs

@@ -128,7 +128,7 @@ public UpdateDialogTransmissionAttachmentUrlDtoValidator()
     {
         RuleFor(x => x.Url)
             .NotNull()
-            .IsValidUri()
+            .IsValidHttpsUrl()
             .MaximumLength(Constants.DefaultMaxUriLength);
         RuleFor(x => x.ConsumerType)
             .IsInEnum();
@@ -273,7 +273,7 @@ public UpdateDialogDialogAttachmentUrlDtoValidator()
     {
         RuleFor(x => x.Url)
             .NotNull()
-            .IsValidUri()
+            .IsValidHttpsUrl()
             .MaximumLength(Constants.DefaultMaxUriLength);
         RuleFor(x => x.ConsumerType)
             .IsInEnum();
@@ -300,7 +300,7 @@ public UpdateDialogDialogGuiActionDtoValidator(
             .MaximumLength(Constants.DefaultMaxStringLength);
         RuleFor(x => x.Url)
             .NotNull()
-            .IsValidUri()
+            .IsValidHttpsUrl()
             .MaximumLength(Constants.DefaultMaxUriLength);
         RuleFor(x => x.AuthorizationAttribute)
             .MaximumLength(Constants.DefaultMaxStringLength);
@@ -345,7 +345,7 @@ public UpdateDialogDialogApiActionEndpointDtoValidator()
             .MaximumLength(Constants.DefaultMaxStringLength);
         RuleFor(x => x.Url)
             .NotNull()
-            .IsValidUri()
+            .IsValidHttpsUrl()
             .MaximumLength(Constants.DefaultMaxUriLength);
         RuleFor(x => x.HttpMethod)
             .IsInEnum();

src/Digdir.Tool.Dialogporten.GenerateFakeData/DialogGenerator.cs

@@ -262,7 +262,7 @@ public static List<CreateDialogDialogActivityDto> GenerateFakeDialogActivities(i
         return new Faker<CreateDialogDialogActivityDto>()
             .RuleFor(o => o.Id, () => Uuid7.NewUuid7().ToGuid(true))
             .RuleFor(o => o.CreatedAt, f => f.Date.Past())
-            .RuleFor(o => o.ExtendedType, f => new Uri(f.Internet.UrlWithPath()))
+            .RuleFor(o => o.ExtendedType, f => new Uri(f.Internet.UrlWithPath(Uri.UriSchemeHttps)))
             .RuleFor(o => o.Type, f => type ?? f.PickRandom(activityTypes))
             .RuleFor(o => o.PerformedBy, f => new CreateDialogDialogActivityPerformedByActorDto { ActorType = ActorType.Values.PartyRepresentative, ActorName = f.Name.FullName() })
             .RuleFor(o => o.Description, (f, o) => o.Type == DialogActivityType.Values.Information ? GenerateFakeLocalizations(f.Random.Number(4, 8)) : null)
@@ -280,19 +280,19 @@ public static List<CreateDialogDialogApiActionDto> GenerateFakeDialogApiActions(
     public static List<CreateDialogDialogApiActionEndpointDto> GenerateFakeDialogApiActionEndpoints()
     {
         return new Faker<CreateDialogDialogApiActionEndpointDto>()
-            .RuleFor(o => o.Url, f => new Uri(f.Internet.UrlWithPath()))
+            .RuleFor(o => o.Url, f => new Uri(f.Internet.UrlWithPath(Uri.UriSchemeHttps)))
             .RuleFor(o => o.HttpMethod, f => f.PickRandom<HttpVerb.Values>())
             .RuleFor(o => o.Version, f => "v" + f.Random.Number(100, 999))
             .RuleFor(o => o.Deprecated, f => f.Random.Bool())
-            .RuleFor(o => o.RequestSchema, f => new Uri(f.Internet.UrlWithPath()))
-            .RuleFor(o => o.ResponseSchema, f => new Uri(f.Internet.UrlWithPath()))
-            .RuleFor(o => o.DocumentationUrl, f => new Uri(f.Internet.UrlWithPath()))
+            .RuleFor(o => o.RequestSchema, f => new Uri(f.Internet.UrlWithPath(Uri.UriSchemeHttps)))
+            .RuleFor(o => o.ResponseSchema, f => new Uri(f.Internet.UrlWithPath(Uri.UriSchemeHttps)))
+            .RuleFor(o => o.DocumentationUrl, f => new Uri(f.Internet.UrlWithPath(Uri.UriSchemeHttps)))
             .Generate(new Randomizer().Number(min: 1, 4));
     }
 
     public static string GenerateFakeProcessUri()
     {
-        return new Faker().Internet.UrlWithPath();
+        return new Faker().Internet.UrlWithPath(Uri.UriSchemeHttps);
     }
 
     public static List<CreateDialogDialogGuiActionDto> GenerateFakeDialogGuiActions()
@@ -317,7 +317,7 @@ public static List<CreateDialogDialogGuiActionDto> GenerateFakeDialogGuiActions(
                 hasPrimary = true;
                 return DialogGuiActionPriority.Values.Primary;
             })
-            .RuleFor(o => o.Url, f => new Uri(f.Internet.UrlWithPath()))
+            .RuleFor(o => o.Url, f => new Uri(f.Internet.UrlWithPath(Uri.UriSchemeHttps)))
             .RuleFor(o => o.Title, f => GenerateFakeLocalizations(f.Random.Number(1, 3)))
             .Generate(new Randomizer().Number(min: 1, 4));
     }
@@ -336,7 +336,7 @@ public static List<CreateDialogDialogAttachmentDto> GenerateFakeDialogAttachment
     public static List<CreateDialogDialogAttachmentUrlDto> GenerateFakeDialogAttachmentUrls()
     {
         return new Faker<CreateDialogDialogAttachmentUrlDto>()
-            .RuleFor(o => o.Url, f => new Uri(f.Internet.UrlWithPath()))
+            .RuleFor(o => o.Url, f => new Uri(f.Internet.UrlWithPath(Uri.UriSchemeHttps)))
             .RuleFor(o => o.ConsumerType, f => f.PickRandom<AttachmentUrlConsumerType.Values>())
             .Generate(new Randomizer().Number(1, 3));
     }