Resource signing

Netherlands - Generic Functions for data exchange Implementation Guide - Local Development build (v0.10.0) built by the FHIR (HL7® FHIR® Standard) Build Tools. See the Directory of published versions

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Introduction
Worked example
Conformance to the FHIR JWS rules
Verifying the signature

Introduction

This page explains how to create and verify a FHIR digital signature for a mutation submitted to the LRZa Directory, by worked example. Signing is optional (see the Mutation signing (optional) and the Provenance entity); this page shows how to produce a correct signature when a party chooses to sign.

The mechanism follows the FHIR Digital Signatures specification: a detached JSON Web Signature (JWS, RFC 7515) computed over the canonical JSON form of the signed resource.

Key choices in this Implementation Guide:

What is signed: a single mutated resource (here an OrganizationAffiliation mandate), not a Bundle.
Canonicalization: http://hl7.org/fhir/canonicalization/json#static — the FHIR static JSON canonicalization. This recursively removes Resource.meta and every narrative (.text) element, and then applies the JSON Canonicalization Scheme (JCS), RFC 8785. Removing meta makes the signature robust as the resource moves from the LRZa Directory to replicas (where meta.versionId, meta.lastUpdated and tags differ).
Signature carrier: a Provenance resource whose signature.data holds the base64 of the detached JWS.
Algorithm: RS256 (RSASSA-PKCS1-v1_5 with SHA-256), matching the example RSA key below. Any JWA algorithm agreed in the trust framework MAY be used.

Worked example

The signed resource is the mandate OrganizationAffiliation "Organization 2 authorizes ExampleSoft"; the resulting signature is carried by Provenance b7d9e2a1-4c3f-5a6b-8e0d-1f2a3b4c5d6e.

Preconditions

Before the steps below can be carried out, the following preconditions SHALL be met:

Stored resource available. The resource to be signed (the OrganizationAffiliation mandate) has been successfully created/updated and is available in its exact stored form.
Signing key and certificate. The signer holds a private key and a matching X.509 certificate. The certificate is valid (not expired or revoked), is issued under a trust anchor accepted by the trust framework (e.g. UZI or PKIoverheid), and its key usage permits digital signatures.
Identity binding. The certificate carries a Subject Alternative Name (SAN) that identifies the signer with an identifier (here the URA 22222222 in its OID‑URN form urn:oid:2.16.528.1.1007.3.3.22222222) that is also recorded in Signature.who/agent.who of the Provenance.
Tooling. A JCS (RFC 8785) canonicalizer and a JWS (RFC 7515) implementation are available to both signer and verifier.

Step 1 — Start with the stored resource

Take the resource exactly as stored by the LRZa Directory after the create/update completed:

{
  "resourceType": "OrganizationAffiliation",
  "id": "c5d6c9d6-7562-589e-9b34-c20a3488daa1",
  "meta": {
    "profile": [
      "http://minvws.github.io/generiekefuncties-docs/StructureDefinition/nl-gf-organizationaffiliation"
    ]
  },
  "identifier": [
    {
      "assigner": {
        "identifier": {
          "system": "http://fhir.nl/fhir/NamingSystem/ura",
          "value": "22222222",
          "type": { "coding": [ { "code": "custodian", "system": "http://terminology.hl7.org/CodeSystem/provenance-participant-type" } ] }
        }
      },
      "system": "urn:ietf:rfc:3986",
      "value": "urn:uuid:6a41ef31-c95a-4894-a6ef-4c39d8ea3e2a",
      "use": "official"
    }
  ],
  "participatingOrganization": {
    "identifier": {
      "system": "http://fhir.nl/fhir/NamingSystem/kvk",
      "value": "90001234"
    },
    "display": "ExampleSoft B.V."
  },
  "code": [
    { "coding": [ { "code": "lrza-careprovider-admin", "system": "http://minvws.github.io/generiekefuncties-docs/CodeSystem/nl-gf-authorization-type-cs", "display": "LRZa Care Provider Administration" } ] }
  ],
  "active": true,
  "organization": { "reference": "Organization/ca56444f-f98c-5d9b-aad2-65a0729ac8f8" }
}

Step 2 — Strip the elements excluded by `#static`

For canonicalization #static, recursively remove every Resource.meta and every narrative (.text). In this resource there is no narrative, so only meta is removed. Everything else — including id and references to other resources — is retained and signed.

Step 3 — Apply the canonicalization (RFC 8785 / JCS)

Canonicalize the stripped resource with the JSON Canonicalization Scheme (RFC 8785). Object keys are sorted, insignificant whitespace is removed, and strings/numbers are serialized deterministically. You can reproduce this with any JCS implementation, e.g. the online JSON Canonicalizer. The canonical form (a single line, shown wrapped here) is:

{"active":true,"code":[{"coding":[{"code":"lrza-careprovider-admin","display":"LRZa Care Provider Administration","system":"http://minvws.github.io/generiekefuncties-docs/CodeSystem/nl-gf-authorization-type-cs"}]}],"id":"c5d6c9d6-7562-589e-9b34-c20a3488daa1","identifier":[{"assigner":{"identifier":{"system":"http://fhir.nl/fhir/NamingSystem/ura","type":{"coding":[{"code":"custodian","system":"http://terminology.hl7.org/CodeSystem/provenance-participant-type"}]},"value":"22222222"}},"system":"urn:ietf:rfc:3986","use":"official","value":"urn:uuid:6a41ef31-c95a-4894-a6ef-4c39d8ea3e2a"}],"organization":{"reference":"Organization/ca56444f-f98c-5d9b-aad2-65a0729ac8f8"},"participatingOrganization":{"display":"ExampleSoft B.V.","identifier":{"system":"http://fhir.nl/fhir/NamingSystem/kvk","value":"90001234"}},"resourceType":"OrganizationAffiliation"}

This canonical text is the JWS payload.

Step 4 — Sign with the private key (detached JWS)

The signer is, for this OrganizationAffiliation, the care provider (Organization 2), using its certificate's private key. For this worked example we use the following published developmental RSA 2048 key — it is a test key only and SHALL NOT be used in production:

The signer's certificate (whose public key matches the key above) carries a Subject Alternative Name (SAN) that identifies the care provider: the URI urn:oid:2.16.528.1.1007.3.3.22222222, which is the OID‑URN form of URA 22222222 (Organization 2). The base64 DER of this certificate goes into the JWS x5c header, and the same identifier is recorded in agent.who.identifier, so a verifier can bind the cryptographic signer to the FHIR resource:

Build the JWS:

Prepare the JWS protected header. alg = RS256; the canonicalization is recorded in the canon header, the signing time in sigT, and the signature purpose in srCms (which SHALL agree with Signature.type), and x5c — the base64 DER of the certificate above, from which the verifier obtains the public key (a kid MAY be used instead). The line below is the exact header serialization that is base64url‑encoded (the long x5c value is the certificate DER):

{"alg":"RS256","typ":"JOSE","canon":"http://hl7.org/fhir/canonicalization/json#static","sigT":"2026-07-14T10:15:00Z","srCms":[{"commId":{"id":"urn:oid:1.2.840.10065.1.12.1.1","desc":"Author's Signature"}}],"x5c":["MIIDdjCCAl6gAwIBAgIGAXQvSnr8MA0GCSqGSIb3DQEBCwUAMDgxNjA0BgNVBAMMLVRlc3QgY2VydGlmaWNhdGUgbWF0Y2hpbmcgcjIwNDhwcml2YXRla2V5LnBlbTAeFw0yNjA3MTQxMzA1MjJaFw0zNzA3MTQxMzA1MjJaMDgxNjA0BgNVBAMMLVRlc3QgY2VydGlmaWNhdGUgbWF0Y2hpbmcgcjIwNDhwcml2YXRla2V5LnBlbTCCASIwDQYJKoZIhvcNAQEBBQADggEPADCCAQoCggEBAKbSmchT0rb5jpW9FooTgYZR1K+sBQxwvrVu4SQLnX00OZh2UKQfD6DM9O7nWQPnRvHYVCD5Jl5adU4ERHmEx3YcYbn9MvxoW6Wb+ST2B8d8GrTvh1jtqmJI0TBHK1oTzHWlZEv13v5YmjHKMOI2KFmhZvFaG3mLMlQ9m1lncpeI6ExBE5tWeO0Z530deZFYVbnVaw8xBZjOJ11f+nZiINfOESROIbbcARcUfKmQkAsE4iZrKMicX1EdBrOHjynObAdDU5JhWXOZJUEorXeu0SZ9pXYW6hOxKQ5eF5SLflMiyZtYLggZbYmvAIJHu3V7oaQe4UOiycGOBI87YZCfCD8CAwEAAaOBhTCBgjAdBgNVHQ4EFgQU68unI5uJMko9US4//OoqtmLDNP4wHwYDVR0jBBgwFoAU68unI5uJMko9US4//OoqtmLDNP4wDwYDVR0TAQH/BAUwAwEB/zAvBgNVHREEKDAmhiR1cm46b2lkOjIuMTYuNTI4LjEuMTAwNy4zLjMuMjIyMjIyMjIwDQYJKoZIhvcNAQELBQADggEBABxjyCCZbBXZVUPBVJUc5Q6mH2XsH1qW6vqNAuTGJb4aiV1+D0Ljw3jmxrq7dzO+CPpAxaLYrv/+d2yT6pufNQx+Yfx2129l0tfHb9admzqvKdjKs1UjDFAgqyAQ3bMRtn1mu13tZqNEnHZgPEyefX7OpnDgDLnzoGi7s74P96XiuDxy0BqtCPzi4LM7UHw4EYOmoA/rwH76JfJSPa5ZA4x8z9jba9/S+MPy1G1uPmHAVCZToCmMysbHKza/Ut/kXTRgRSzllo7/+4XI4K2PRwUdGSnbrNmabvd5k2jkufTtrxSQZEIhVOHT8E5eDk1K6F5ILXN9NgzmM8acw2EyHYg="]}

base64url‑encode the header and the canonical payload from step 3, and join them with a .: BASE64URL(header) + "." + BASE64URL(payload).
Sign that header.payload string with RS256 (RSASSA-PKCS1-v1_5 over SHA-256).

Detach the payload — replace it with an empty string, giving the compact detached JWS header..signature:

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..EZEsnaJ4BP-PZN1SZPNbdwWPs2llnAXdynIDNOQQG9x3LbxwR-qDuHPcMdUrU5ikDUZJlPyxEc83Juodxj8KRhEPRp5eJEBiXu5NefQDonXf7sue3WoQUuMu-lBhHnF0C3oCg2Ry2UFwIVenxE-M9xkbUtYQ1Ui4cnRQFtR3swVyUkp7XPqjGvuJg_2AUjn5U4jecN5zVC9IQ51rtaRUGHiSEyzTRkzqyJcseakK3EZMbcubrS06Jf_1Kb1mxl9vOBLdaTUXq_idQ9GvNucY6Ajy6hCKjMc0a9N2oBlFsGdt9sYXtvCaWeguoL8ApEFLTz4uPmRPAmjtWE76gz9eaA

Step 5 — base64‑encode the JWS into `Signature.data`

Signature.data is base64Binary, so the compact detached JWS (which itself uses base64url) is base64‑encoded once more (this double‑encoding is required by the FHIR JSON signature rules). The result is the signature.data value placed in the Provenance:

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

Step 6 — Assemble the Provenance

The signature is carried by a Provenance that targets the signed resource. Per FHIR, signature.type, signature.when and signature.who mirror agent.type, recorded and agent.who. Show the resulting Provenance as JSON:

{
  "resourceType": "Provenance",
  "id": "b7d9e2a1-4c3f-5a6b-8e0d-1f2a3b4c5d6e",
  "target": [
    {
      "reference": "OrganizationAffiliation/c5d6c9d6-7562-589e-9b34-c20a3488daa1"
    }
  ],
  "agent": [
    {
      "who": {
        "identifier": {
          "system": "urn:oid:2.16.528.1.1007.3.3",
          "value": "22222222"
        },
        "reference": "Organization/ca56444f-f98c-5d9b-aad2-65a0729ac8f8"
      },
      "type": {
        "coding": [
          {
            "code": "author",
            "system": "http://terminology.hl7.org/CodeSystem/provenance-participant-type"
          }
        ]
      }
    }
  ],
  "signature": [
    {
      "type": [
        {
          "code": "1.2.840.10065.1.12.1.1",
          "system": "urn:iso-astm:E1762-95:2013",
          "display": "Author's Signature"
        }
      ],
      "who": {
        "identifier": {
          "system": "urn:oid:2.16.528.1.1007.3.3",
          "value": "22222222"
        },
        "reference": "Organization/ca56444f-f98c-5d9b-aad2-65a0729ac8f8"
      },
      "when": "2026-07-14T10:15:00Z",
      "targetFormat": "application/fhir+json;canonicalization=http://hl7.org/fhir/canonicalization/json#static",
      "sigFormat": "application/jose",
      "data": "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"
    }
  ],
  "recorded": "2026-07-14T10:15:00Z"
}

Both agent.who and signature.who carry a reference to the Organization and an identifier (URA 22222222, system urn:oid:2.16.528.1.1007.3.3). Its OID‑URN form urn:oid:2.16.528.1.1007.3.3.22222222 equals the certificate's Subject Alternative Name, satisfying the FHIR rule that Signature.who SHALL contain an identifier that is also found in the X.509 certificate.

The rendered resource is Provenance b7d9e2a1-4c3f-5a6b-8e0d-1f2a3b4c5d6e.

Conformance to the FHIR JWS rules

The signature above is checked against the JWS/JSON signature rules:

FHIR JWS rule	Status	How it is met
`Signature.data` is the base64 of a compact-serialization JWS (double-encoded)	✅ SHALL	`signature.data` = base64( `header..signature` )
`sigFormat` = `application/jose`	✅ SHOULD	populated
`targetFormat` populated with a canonicalization URL (`canon` header MAY also)	✅ SHOULD	`application/fhir+json;canonicalization=…/json#static` and `canon` header agree
Detached signature, payload omitted	✅ SHALL	JWS is `header..signature` (empty payload)
Signed across the canonical JSON form indicated by `targetFormat`	✅ SHALL	RFC 8785 JCS after `#static` stripping
`Signature.who` present with a `reference`/`identifier` matching an identifier in the X.509 certificate	✅ SHALL	`who.identifier` (URA 22222222) equals the certificate SAN `urn:oid:2.16.528.1.1007.3.3.22222222`
Protected header contains `kid` or `x5c`	✅ SHALL	`x5c` = base64 DER of the certificate
`srCms` signer-commitment present; `Signature.type` from ASTM E1762-95(2013); the two agree	✅ SHALL	`srCms.commId.id` = `urn:oid:1.2.840.10065.1.12.1.1` = `Signature.type`
`sigT` present, `Signature.when` present, and they agree	✅ SHOULD	both = `2026-07-14T10:15:00Z`
Conform to JAdES-B-T	➖ MAY	the JAdES-B-T elements `srCms` and `sigT` are present; a full JAdES-B-T signed-properties structure is not modelled
Conform to JAdES-B-LTA (long-term: timestamp token + revocation data)	➖ SHOULD	the signing certificate is embedded via `x5c`; a trusted timestamp token and revocation data are out of scope of this example

Provenance-specific rules (Digital Signatures in Provenance): FHIR R6 notes that signature.type/when/who duplicate agent.type/occurredDateTime/agent.who and should not be used. This IG targets FHIR R4, so these Signature elements are retained; they agree with the corresponding agent/recorded values as required.

The two open items (JAdES-B-T / JAdES-B-LTA) are optional profiling for long-term validation; adding a qualified timestamp token and revocation data is a natural extension when long-term non-repudiation is required.

Verifying the signature

A replica, auditor or supervisor verifies as the mirror of the signing steps:

Retrieve the target resource (OrganizationAffiliation) as replicated.
Remove Resource.meta and every narrative (.text) — the #static exclusions.
Canonicalize with RFC 8785 (JCS) to reproduce the payload of step 3.
base64‑decode signature.data to recover the compact detached JWS, and re‑insert the base64url‑encoded payload between the two dots.
Read the public key from the JWS header (x5c/kid), and cryptographically verify the JWS with the algorithm in alg.
Confirm the certificate itself is trusted (issuer, validity, key usage) and that signature.who matches an identifier in the certificate.

Because both signer and verifier apply the same canonicalization (json#static), the exact signed byte sequence is reproducible even though meta.versionId/meta.lastUpdated differ between the LRZa Directory and each replica.

The signature.data in this example is a real RS256 signature over the canonical JSON above, produced with the published developmental test key. It verifies cryptographically, but the key is not trusted for any production use.