feat(federation): Step-CA client service for grant certs (FED-M2-04) (#494)

apps/gateway/src/federation/ca.dto.ts

@@ -0,0 +1,57 @@
+/**
+ * DTOs for the Step-CA client service (FED-M2-04).
+ *
+ * IssueCertRequestDto  — input to CaService.issueCert()
+ * IssuedCertDto        — output from CaService.issueCert()
+ */
+
+import { IsInt, IsNotEmpty, IsOptional, IsString, IsUUID, Max, Min } from 'class-validator';
+
+export class IssueCertRequestDto {
+  /**
+   * PEM-encoded PKCS#10 Certificate Signing Request.
+   * The CSR must already include the desired SANs.
+   */
+  @IsString()
+  @IsNotEmpty()
+  csrPem!: string;
+
+  /**
+   * UUID of the federation_grants row this certificate is being issued for.
+   * Embedded as the `mosaic_grant_id` custom OID extension.
+   */
+  @IsUUID()
+  grantId!: string;
+
+  /**
+   * UUID of the local user on whose behalf the cert is being issued.
+   * Embedded as the `mosaic_subject_user_id` custom OID extension.
+   */
+  @IsUUID()
+  subjectUserId!: string;
+
+  /**
+   * Requested certificate validity in seconds.
+   * Hard cap: 900 s (15 minutes). Default: 300 s (5 minutes).
+   * The service will always clamp to 900 s regardless of this value.
+   */
+  @IsOptional()
+  @IsInt()
+  @Min(60)
+  @Max(15 * 60)
+  ttlSeconds: number = 300;
+}
+
+export class IssuedCertDto {
+  /** PEM-encoded leaf certificate returned by step-ca. */
+  certPem!: string;
+
+  /**
+   * PEM-encoded full certificate chain (leaf + intermediates + root).
+   * Falls back to `certPem` when step-ca returns no `certChain` field.
+   */
+  certChainPem!: string;
+
+  /** Decimal serial number string of the issued certificate. */
+  serialNumber!: string;
+}