sentryagent-idp/openspec/changes/archive/2026-04-02-phase-3-enterprise/specs/soc2/spec.md

SOC 2 Type II Preparation — Specification

Workstream: 6 of 6 Phase: 3 — Enterprise Author: Virtual Architect Date: 2026-03-29

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Overview

Implement the technical controls required for SOC 2 Type II audit readiness. SOC 2 Type II certifies that security controls operate continuously over a defined period — not just that they exist. Controls are implemented in code, not just documented.

This workstream cuts across all other Phase 3 workstreams. It delivers: encryption at rest for sensitive columns, TLS enforcement middleware, automated secrets rotation, security event alerting, and audit log immutability via a Merkle hash chain. A compliance documentation package (controls matrix and runbook) is produced for auditors.

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Technical Controls

Control C1: Encryption at Rest (Column-Level Encryption)

Sensitive columns in PostgreSQL are encrypted using pgcrypto symmetric encryption. The encryption key is stored in Vault and fetched at application startup, never written to disk.

Columns encrypted:

• credentials.secret_hash — encrypted with AES-256-CBC
• credentials.vault_path — encrypted with AES-256-CBC
• webhook_subscriptions.vault_secret_path — encrypted with AES-256-CBC
• agent_did_keys.vault_key_path — encrypted with AES-256-CBC

Implementation: A EncryptionService wraps pgcrypto pgp_sym_encrypt / pgp_sym_decrypt. The key is a 256-bit symmetric key stored at secret/agentidp/encryption/column-key in Vault. All INSERT/SELECT operations for encrypted columns go through EncryptionService.

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Control C2: TLS Enforcement

All inbound HTTP connections are rejected in production if TLS is not present. This is enforced at two levels:

1. Express middleware: TLSEnforcementMiddleware — if X-Forwarded-Proto is not https and NODE_ENV=production, respond 301 Moved Permanently to HTTPS.
2. Terraform: Load balancers (Phase 2 Terraform modules) already enforce TLS; TLS enforcement middleware provides defense-in-depth.

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Control C3: Automated Secrets Rotation

A scheduled job (SecretsRotationJob) runs on a configurable cron schedule. It:

1. Identifies credentials whose expires_at is within ROTATION_WARNING_DAYS days
2. Emits a Prometheus metric agentidp_credentials_expiring_soon_total (labelled by org_id, days_remaining)
3. Renews Vault leases for all active credentials
4. Sends a webhook event credential.expiring_soon to subscribers who have opted in

This does not automatically rotate credentials without operator action — it alerts and prepares. Forced rotation requires an operator call to the existing POST /agents/:id/credentials/:credId/rotate endpoint.

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Control C4: Audit Log Immutability (Merkle Hash Chain)

Every audit_logs row carries two new columns:

• hash: SHA-256 of (eventId || timestamp.toISOString() || action || outcome || agentId || organizationId || previousHash)
• previous_hash: hash of the immediately preceding audit_logs row (by created_at order), or the genesis string "GENESIS" for the first row

A PostgreSQL trigger prevents UPDATE and DELETE on audit_logs.

A new admin endpoint GET /audit/verify runs a sequential chain verification pass and returns the integrity status.

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Control C5: Security Event Alerting

Prometheus alerting rules are written for the following security events:

Alert	Condition	Severity
AuthFailureSpike	>50 auth.failed events in 5 minutes	Warning
RateLimitExhaustion	>80% of org rate limit consumed in 1 minute	Warning
AnomalousTokenIssuance	Token issuance rate 3x 7-day average	Warning
WebhookDeadLetterAccumulating	agentidp_webhook_dead_letters_total increases by >10 in 1 hour	Warning
AuditChainIntegrityFailed	agentidp_audit_chain_integrity metric is 0	Critical
CredentialExpiryApproaching	agentidp_credentials_expiring_soon_total{days_remaining="7"} > 0	Info

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API Endpoints

GET /audit/verify

Verify the Merkle hash chain integrity of the audit log. Requires admin:orgs scope. This is a potentially expensive operation on large audit logs — it is rate-limited to once per 5 minutes per organization.

GET /audit/verify
Authorization: Bearer <token with admin:orgs scope>

Query Parameters:
  fromDate:
    type: string
    format: date-time
    description: Start of verification range. If omitted, verifies from genesis.
  toDate:
    type: string
    format: date-time
    description: End of verification range. If omitted, verifies to the latest row.

Responses:
  200 OK:
    schema:
      type: object
      properties:
        valid:
          type: boolean
          description: True if the chain is intact across the entire range
        rowsVerified:
          type: integer
          description: Number of audit rows verified
        firstEventId:
          type: string
        lastEventId:
          type: string
        firstTimestamp:
          type: string
          format: date-time
        lastTimestamp:
          type: string
          format: date-time
        verifiedAt:
          type: string
          format: date-time
        brokenAtEventId:
          type: string
          nullable: true
          description: Present only if valid=false — the first eventId where the chain breaks
    example:
      valid: true
      rowsVerified: 15420
      firstEventId: "evt_genesis_00001"
      lastEventId: "evt_01HXK7Z9P3FKWABCDEFZZZZZ"
      firstTimestamp: "2026-01-01T00:00:00Z"
      lastTimestamp: "2026-03-29T12:00:00Z"
      verifiedAt: "2026-03-29T14:00:00Z"
      brokenAtEventId: null
  401 Unauthorized:
    schema:
      $ref: '#/components/schemas/ErrorResponse'
  403 Forbidden:
    schema:
      $ref: '#/components/schemas/ErrorResponse'
  429 Too Many Requests:
    schema:
      $ref: '#/components/schemas/ErrorResponse'
    example:
      code: "RATE_LIMITED"
      message: "Audit verification can be run at most once per 5 minutes"

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GET /compliance/controls

Returns the current status of all SOC 2 technical controls. Requires admin:orgs scope. Used by auditors and compliance dashboards.

GET /compliance/controls
Authorization: Bearer <token with admin:orgs scope>

Responses:
  200 OK:
    schema:
      type: object
      properties:
        generatedAt:
          type: string
          format: date-time
        controls:
          type: array
          items:
            type: object
            properties:
              controlId:
                type: string
              name:
                type: string
              status:
                type: string
                enum: [pass, fail, warning, not_applicable]
              description:
                type: string
              lastChecked:
                type: string
                format: date-time
    example:
      generatedAt: "2026-03-29T14:00:00Z"
      controls:
        - controlId: "C1"
          name: "Encryption at Rest"
          status: "pass"
          description: "Column-level encryption active for all sensitive columns"
          lastChecked: "2026-03-29T14:00:00Z"
        - controlId: "C2"
          name: "TLS Enforcement"
          status: "pass"
          description: "All non-TLS requests redirected to HTTPS in production"
          lastChecked: "2026-03-29T14:00:00Z"
        - controlId: "C3"
          name: "Secrets Rotation"
          status: "warning"
          description: "3 credentials expiring within 7 days"
          lastChecked: "2026-03-29T14:00:00Z"
        - controlId: "C4"
          name: "Audit Log Immutability"
          status: "pass"
          description: "Merkle chain intact — last verified 2026-03-29T13:55:00Z"
          lastChecked: "2026-03-29T14:00:00Z"
        - controlId: "C5"
          name: "Security Event Alerting"
          status: "pass"
          description: "All 6 alerting rules active in Prometheus"
          lastChecked: "2026-03-29T14:00:00Z"
  401 Unauthorized:
    schema:
      $ref: '#/components/schemas/ErrorResponse'
  403 Forbidden:
    schema:
      $ref: '#/components/schemas/ErrorResponse'

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Database Schema Changes

Modified: audit_logs table

ALTER TABLE audit_logs
  ADD COLUMN hash          VARCHAR(64),   -- SHA-256 hex string of chain node
  ADD COLUMN previous_hash VARCHAR(64);   -- Hash of preceding row, or "GENESIS"

-- Back-fill genesis hash for existing rows (one-time migration)
-- Migration script computes chain in order of created_at

-- Prevent updates and deletes (immutability trigger)
CREATE OR REPLACE FUNCTION prevent_audit_modification()
RETURNS TRIGGER AS $$
BEGIN
  RAISE EXCEPTION 'audit_logs rows are immutable — modification is not permitted';
END;
$$ LANGUAGE plpgsql;

CREATE TRIGGER audit_logs_immutability
  BEFORE UPDATE OR DELETE ON audit_logs
  FOR EACH ROW EXECUTE FUNCTION prevent_audit_modification();

Modified: credentials table

-- Columns remain same type; application now stores encrypted values
-- No DDL change — encryption is transparent at application layer
-- Add comment for documentation
COMMENT ON COLUMN credentials.secret_hash IS 'AES-256-CBC encrypted via EncryptionService (pgcrypto). Not a plain bcrypt hash.';
COMMENT ON COLUMN credentials.vault_path IS 'AES-256-CBC encrypted via EncryptionService.';

New Table: compliance_check_log

CREATE TABLE compliance_check_log (
  check_id         VARCHAR(40)  PRIMARY KEY,
  organization_id  VARCHAR(40)  NOT NULL REFERENCES organizations(organization_id),
  control_id       VARCHAR(10)  NOT NULL,
  status           VARCHAR(20)  NOT NULL,
  details          JSONB        NOT NULL DEFAULT '{}',
  checked_at       TIMESTAMPTZ  NOT NULL DEFAULT NOW()
);

CREATE INDEX idx_compliance_check_org ON compliance_check_log(organization_id, checked_at DESC);

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Configuration

Environment Variable	Description	Default
SOC2_CONTROLS_ENABLED	Enable SOC 2 controls enforcement	true
TLS_ENFORCEMENT_ENABLED	Enforce HTTPS in production	true in production, false in development
COLUMN_ENCRYPTION_KEY_PATH	Vault path for AES-256 column encryption key	secret/agentidp/encryption/column-key
ROTATION_WARNING_DAYS	Days before expiry to emit rotation warning	30
SECRETS_ROTATION_CRON	Cron schedule for rotation check job	0 3 * * * (daily at 3 AM UTC)
AUDIT_CHAIN_VERIFY_CRON	Cron schedule for automated chain verification	0 2 * * * (daily at 2 AM UTC)

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Dependencies

Package	Version	Purpose
node-forge	^1.3.1	AES-256-CBC column-level encryption primitives

Note: pgcrypto PostgreSQL extension must be enabled: CREATE EXTENSION IF NOT EXISTS pgcrypto;

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Compliance Documentation

The following documents are produced as part of this workstream:

Document	Path	Description
Controls Matrix	docs/compliance/soc2-controls-matrix.md	Maps SOC 2 Trust Services Criteria to implemented controls
Encryption Runbook	docs/compliance/encryption-runbook.md	Key rotation procedure, Vault key path map
Audit Log Runbook	docs/compliance/audit-log-runbook.md	How to run chain verification, interpret results
Incident Response	docs/compliance/incident-response.md	Security event response procedures
Secrets Rotation Guide	docs/compliance/secrets-rotation.md	Operator guide for credential and key rotation

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Security Considerations

• Column encryption key is fetched from Vault at startup and held in process memory — never written to disk or logged
• Key rotation: new encryption key generates re-encrypted copies of all sensitive columns in a migration; the old key is retained in Vault history
• The immutability trigger on audit_logs prevents application-layer modification; a SUPERUSER can still bypass triggers — document this in the controls matrix as a residual risk requiring compensating controls (e.g., read-only replica verification)
• GET /audit/verify is rate-limited to prevent denial-of-service via repeated expensive sequential scans
• GET /compliance/controls never returns raw secrets or key material — only control status

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Acceptance Criteria

• pgcrypto extension enabled; sensitive columns are encrypted at rest (verified: plaintext not visible in direct DB query)
• TLS enforcement middleware redirects HTTP to HTTPS in production; passthrough in development
• SecretsRotationJob runs on schedule; emits Prometheus metric for expiring credentials
• Audit log immutability trigger prevents UPDATE/DELETE on audit_logs table
• GET /audit/verify returns valid: true for an unmodified chain
• GET /audit/verify returns valid: false with brokenAtEventId after a row is manually tampered with (test scenario)
• All 6 Prometheus alerting rules are present in monitoring/prometheus/alerts.yml
• GET /compliance/controls returns correct status for all 5 controls
• Compliance documentation written and reviewed
• TypeScript strict, zero any, >80% test coverage on SOC2 control implementations