Post-Quantum Algorithms for HTTP Message Signatures

Version: v0.2.0
Authors:
- Soatok Dreamseeker

Introduction §

This document specifies HTTP Message Signature algorithm identifiers for post-quantum signature schemes. As of v0.1.0, this only covers the ML-DSA signature algorithms standardized in FIPS 204.

HTTP Message Signatures are specified by RFC 9421. This document only defines new signature algorithms for that framework. Signature base construction, the Signature-Input field, the Signature field, and message verification are otherwise unchanged.

Conventions used in this document §

The base64 encoding used throughout is the standard Base 64 encoding specified in RFC 4648, Section 4.

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14 RFC 2119 RFC 8174 when, and only when, they appear in all capitals, as shown here.

Algorithms §

The following values are defined for use in the RFC 9421 alg signature parameter.

`alg` value	FIPS 204 algorithm	Public key size	Signature size
`ml-dsa-44`	ML-DSA-44	1312 bytes	2420 bytes
`ml-dsa-65`	ML-DSA-65	1952 bytes	3309 bytes
`ml-dsa-87`	ML-DSA-87	2592 bytes	4627 bytes

For each algorithm, the public key is the raw FIPS 204 public key encoding for that parameter set.

The message to sign is the RFC 9421 signature base, exactly as bytes. Signers MUST use the FIPS 204 ML-DSA signing operation for the selected parameter set with an empty context string. Verifiers MUST use the corresponding FIPS 204 ML-DSA verification operation with an empty context string.

The Signature field value is the raw FIPS 204 signature encoded as an RFC 9421 byte sequence. No prehashing, external-mu processing, or additional framing is defined by this document.

When the alg parameter is present, verifiers MUST reject signatures where the algorithm does not match the configured verification key's ML-DSA parameter set.

Signing and Verification §

For the selected alg value, HTTP_SIGN(M, Ks) takes the RFC 9421 signature base bytes M and a raw FIPS 204 ML-DSA private key Ks for the corresponding parameter set, and returns the raw FIPS 204 signature S.

HTTP_SIGN MUST call the FIPS 204 signing operation for the selected parameter set directly on M, with the context string set to the empty string. HTTP_SIGN MUST NOT prehash M, use external-mu processing, or add any framing around M.

For the selected alg value, HTTP_VERIFY(M, Kv, S) takes the regenerated RFC 9421 signature base bytes M, a raw FIPS 204 ML-DSA public key Kv for the corresponding parameter set, and a raw FIPS 204 signature S, and returns true if the signature is valid and false otherwise.

HTTP_VERIFY MUST call the FIPS 204 verification operation for the selected parameter set directly on M and S, with the context string set to the empty string. HTTP_VERIFY MUST NOT prehash M, use external-mu processing, or add any framing around M.

Implementations MUST reject malformed public keys, malformed signatures, values with lengths that do not match the selected parameter set, and any signature where the alg value does not match the configured key's ML-DSA parameter set. Implementations that expose FIPS 204 options MUST invoke verification with the context string set to the empty string and the unhashed signature base M as the message. Verification with a non-empty context string, a prehashed digest, external-mu processing, or any other representation of M MUST fail for these algorithms.

Test vectors §

The seed deterministically generates the key pair. ML-DSA signing is randomized, so the signatures below are sample valid signatures and are not reproduced from the seed alone.

ML-DSA-44 §

Algorithm: ml-dsa-44

Seed:

c80d699b2daa47d54b8697f5a917c696400d7063b30a234d18ad672250ae42d9

Signature base:

"@method": GET
"@target-uri": https://example.com/foo?param=Value&Pet=dog
"host": example.com
"date": Mon, 06 Jul 2026 20:00:00 GMT
"@signature-params": ("@method" "@target-uri" "host" "date");created=1783368000;keyid="test-key-mldsa44";alg="ml-dsa-44"

Serialized Signature-Input field:

Signature-Input: sig1=("@method" "@target-uri" "host" "date");created=1783368000;keyid="test-key-mldsa44";alg="ml-dsa-44"

Serialized Signature field, where <base64 signature below> is the Signature value below:

Signature: sig1=:<base64 signature below>:

Public key:

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

Signature:

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

ML-DSA-65 §

Algorithm: ml-dsa-65

Seed:

40342eccce31032955f04c14256fa8cb6b6269bdc22d6ee62fd00d9338759773

Signature base:

"@method": GET
"@target-uri": https://example.com/foo?param=Value&Pet=dog
"host": example.com
"date": Mon, 06 Jul 2026 20:00:00 GMT
"@signature-params": ("@method" "@target-uri" "host" "date");created=1783368000;keyid="test-key-mldsa65";alg="ml-dsa-65"

Serialized Signature-Input field:

Signature-Input: sig1=("@method" "@target-uri" "host" "date");created=1783368000;keyid="test-key-mldsa65";alg="ml-dsa-65"

Serialized Signature field, where <base64 signature below> is the Signature value below:

Signature: sig1=:<base64 signature below>:

Public key:

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

Signature:

4xy2CPdN15+foVLxfXbuRu2DbMU/lCTfWvIJ20W83U2rg8b3NiaoW0DE4ZZISfHh0y4d+f6ea/ngMnLjEjiblPks2b+XU7i217hGfS3DDNxm9n5nPxzW8mAQee2Po3OSAjQ/HO1no+STkwWzYYudC9coNbzQOAQ7WxNUb6gCbDXweE9ikZTSXmvxYJIL1/OiIeuXeiAtPM3l7OFMCyvgpebx9988qf0/g1GAXTRiLv4b6DgYh2zxPpdZseMmsfmU0LWQaza0x8RxcrJ7QXUTtwqGA5CjYgtNT22PyIUIIK256uc8iELL5lpDqcyVBy0bG0n8m3CZpDdTE56w2jEqlXSaV8PQ6M3EGwme6gCvkLrzOFORNsLXvhdY9vwZOCjAity4Sn+uOuudbjkts5vou2Zomt/I5icyAmeQOaW6bN7EbpCE5obfZ7GrsaBqYo0z92w92yHMoJ7zHZafjTKnVu0S+qeEmZe7SIAZMx66PTNF2fLaf6VQniUjUjDHV9qmW8vEtca9M0cU0xzeYEuCs3XOMU59OIlzCZcA1p8Yr+weHJWWHHiJU/FEjPIP44wcMyNUwzSkKxr2LkjYpWInYbhPfTIhzZfFKthe3nuLJUZLNPEu/52ENHrOrlORZLODg9eGw6s2iAsP6v5cOFxU93p6rFkd1ekcz8qi/LR/4UkeqI49pOn+3TnVQsjTU3iR3JW86YKpzCwoMXskNPJK/XR45Uxvz+7X23oupFKXai1Z0rMT1eWtjLzzZ279O5jVSq3zSd0zW1oodkkDhNRIhR5JXL02dNjyuufs4YQGIYSobX5yCHCI3RBMJ5MdRPvFx0N41+wvdmE3VFV5UUOGgebproE8DZ//ginPmMKGgD1IyutshH6oWJ0tDms/HVeCEjHKg6gJQDXRpbUM25nkPkyJPCLb234jYz0lHYBoNtXUI9qQUX+nixk6jm/L/1MNzV2YmpwJxRnW0+61rj2b0IR5pVjUJLzxpL5sWLgNNOcTwWqH6seqqKn/4EjFaSKDrN9FMNzXD8NqAmV+ixlbwL2Y57MsYqzVH8xEemk0SSM8o+56Pe1UJM1Bzk01URD3ipAKxnfFltUskRDBkrlntR2tb2ic3/nBLuvPdTmAEQQFaoNs5m5hESyrA7if2zdNVqVk2Ees+tjXYQpWPhaoz1z/f1o4U992XtaBByA9dalHAuBTaQ/vcDiWlZxgNyJs4DymDRbsiV8AiO7jB2AqchoEoqMSmc8zgpEbZslHwRfDCjo5/MZ4yctpfKFMsqtcuZ0n0JPE30DNhYATFG0tB+3JV8HSwbHquqQalnUR+VBnx7nlQ8wrdZhbMM09ovmWV5hSYkF1fpkgKgC/uQVdbevG5Ifc8QqVcOxPnRkQgsySGpRxkLSb0gtwZKMCfvWJHtbOIwO9PTmA11f6uGACzm6oXgY2/Z0KlfxQIIjr7KGYpHoaCXkaKVNqqGU4r33mZiotcZZ3ozi/xIC5N1aX0hspce8PwJh2iAQaZTCPlQxShQIMX7MRPKTQh1TaHtl1Vt40OVPiG0nHsuDvpTNGbkUCAKQ+wvokLhykgl+tNnWm7MUgCSi+Frdj3kau5sm3ZHsL6MFItQ0Bne7lJYsyr+0xXXjEtk9G8TqqHLr6bCWjSuaDvY55zQJn/hLjw4pMb5/oNJGmJBt9n36QvNP9mtHVVoXmmPSySM5o1Y1MReyAuNA63lmQErejdTVHSLABhCvjrw4B96h3MRzrHrCWMX/0W1aJ4XfWBEft2csE6o0XaJbGDZYRvATNOz9ymyISpFQeGgDSapl56O3qOYnBkGHo2WYk+T6BXVJtjGKj5h1dNW9zzOu9b4HYVtzEVedehVmtsrlCOVLK8UlM/9MXb2Aqe2BVp5rgkyCLLFS3f4PfEpRVSfDO3LN+FpQUtk7kl5fmbxFhrON88uUbITlQxFQJuvnHS6mHzWJ9tdeFeU81HILlTwW9QbbqQCnLrpz3uJralsOEXoyoUKK6xO4oMtp2xExI/ZwVcw0pGL9zzXUMQqfboW+i6l8bGTp5j9k29LlMhuKgfS2amTQYwfkjItIekm4ZNcoIXLzhuOren+l34qQeqvJLnK7wDXMeJjKgW16B/zkcgFS8zH5FwXvbLO/Pe+63YZVAungq7ADF9hSqnkP/sT0+JVYLYfHsUZW4CQc800h0ggNAwqYTuUOUCi5pIFdvvp54jOtp3MrG/QCUriUvC7S4rT5nHE9cT8Izz9GB4sLlqb5G3dWIOChoct4Dai4XAI3c5wxFXKxqIqBV7BLPsze1cPK9RHy7q029gUi16Cp37/JIqqsl7hoUiLUt/rTspE++d+Eb1kwUqlj/TvBREHgfPvljAeDe8OxuKq8suqbhkqvFdGX2rVDxvEDTfttE1kZI6fKEfeBpU5pQsEJzOwTOP8IkPJUCcI4LYgIr+AMI8WLZE6YKrdTKR1zPml2evFwP69liTms/TpWFhOWLH5Tm3KMaHAagScaDmQnLx5uM4/wCk374BQ40KGA7yKxtuuZFXxiOPPGmGx+YzZIj/ltEl3medDqywGWWZmDWUgfnUD6yASzpSv9ycwey8H3nRz//7h0xxz/zFVbe4q5AIVOXNubsIV9Xum0nLZtNtIaUI12A8/D0HzafPwMddTxh6QVxEgEt+B8zaMyZhnkw/D4L3El6Rw97lJ1gOqfONCm2wyvmyDo7HFXy+ZtSCyE1Etn3/q+RwCMpEr1OBJfJY7koZYVORfzR8CQsDqDNSw1ul81W7RWKHZpenBlx8Q1kClnFLrMDLc6LNSUuLWET2aCytDuMiCUZglh7DcCaP6qqQ+cNFURKOe16PfU3GoOvm7ESDhfQE9uQo27qxg3Zv30i95nIF4dnbIuCuKa4zUfQTyB2CPhraOddn0Y0NONldiqkzgbPyQIFEtzrPdfCabmg56yfI1Rzag2MVHfKI4H9/m102rVpVpRwviTPYumQQA4jD7toRBJzDPxAbvGj3pXQkK7zPoH63FRDQpGeNG2tUv/Wl8m05AGljiE2JuAs3F6tjfH6OvjZY8ZRx8Odcw0IGsjc6mzupCtfzg7yy9AVLzm8yBlhY8tvaYzyJ6kPhgNvJfxwRBKuRdqcvk51elrE055MQjqnhG/KvRGlp90BrWIUyRdWuJE01lNZfJZ9+wV1dPCp1T+NGY3BPQb2z5d2LoNK1pLQr4AArciNSWwD99gw5gi+iqKc9HolZYqhAxZYBsiKl5uJKsg20mxUVWG7wgMLjB6p9HfbRVMCNUxxXioS02a0lAPAA3jknq6ibaueA9WlRxxiC5oJrqT8K2s/E/ykMSj+BDXgGqQ5BJlZe1XSxj0LCyasClCDP3X+BXWOI4RKSG/0Cfv5KkcfAm5GeFD6n+7n26gNsxCbcZStrEnH9ZFFuhMbJ61pcxUVsFZAAJheZODWs4Zx8KKEK3T71KoCcrX74VrdYGOYWtz76T210r07CxsRc6U4Db+KSa/UEGtWNVNxZaH5Y0hzcV6wBe8elFWXhluL9p1BlN5TpgMgB7MH12n1uo7jA7o/ZJELpz0DWGj5xDpCTvj04jJy4WwYfgZx6MX8vTTe6/f5lUwXTXn/0WHGyLZXYsOco63IeTrMOfyZop4jjb1C8mdrXx1IJCeiAMoqKRSaT8Iwq4haMjgIfqpk3ZB8EXE41zcbXp7aaontwIPpM8pEB2jleWw7LNLjf7xEc14RwVgD0bPs+NbaD67GNrAXXeB+HnErHEDFtoPos4TtZa37FPsVOsu6Tlu3W706TtsB6sVsneVvFOV6nW757FGtrEpI7JhbGnyD3nbpqs1qb4WWJcqhi3PrlL0NSR4nhMqIncZ7wS9LKcm1G//VYgRrNx8dAvorAoS3Q5lsDCj1S0afLZAenPfjL3O23CPPzHA65Ph4+8VR4iHUbB3BFjRswNKxdCYy7LgY8p7qGxBCkPDP0smh9bZPXVu7si0UDlvZKe+EbujjcYGa94DMgUFoQX4NAfST48D2idav+uK8NASWCRiTpPU3CDqHegTTNK3ZMfxYikJ2kOlL1ssRMuD6C59ZyYB9JpQC6IY0xuHAKmJ2WfMOwbfZYmRCq+fDEHvZuA3UXpp2nHuGsrJZ0FIrfYDL2Z4NDRgk2SLA92lovZNe4A7DdJcH8yIkUUbeRseZ7FAPHndia3hO5Jr8hKEhaOai737Zshh1K4h5nxQlSZR+pCaCdNdnb7qO1j7AUyLzywBn63PdIAMiKy7sivVA3Q/2UsQk4Si0UZVkufWt3eGlhM2taleN9rd+gYf5NIXZv8ap/AY8JHdcamw29Ho9ufW2IBOgSYugQxrj6V4QMsPN7Hqs8Q5ZeoKDprvE1u79CQwjc4GgqKq63RAUMnZ7hSU+TGmJ8/gAAAAAAAAAAAAAAAAABQgTHSMq

ML-DSA-87 §

Algorithm: ml-dsa-87

Seed:

0cd2f7cc3f9772ad23031ef37aea63b3825fb46bdb5d5cc4fb620ecccc5e630b

Signature base:

"@method": GET
"@target-uri": https://example.com/foo?param=Value&Pet=dog
"host": example.com
"date": Mon, 06 Jul 2026 20:00:00 GMT
"@signature-params": ("@method" "@target-uri" "host" "date");created=1783368000;keyid="test-key-mldsa87";alg="ml-dsa-87"

Serialized Signature-Input field:

Signature-Input: sig1=("@method" "@target-uri" "host" "date");created=1783368000;keyid="test-key-mldsa87";alg="ml-dsa-87"

Serialized Signature field, where <base64 signature below> is the Signature value below:

Signature: sig1=:<base64 signature below>:

Public key:

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

Signature:

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

Negative test cases §

For each vector above, verifiers MUST reject the following variants. Accepting any of them indicates a bug in signature-base construction, algorithm binding, or strict ML-DSA input validation.

Test	Change	Expected result
Modified component	Change the `date` line from `Mon, 06 Jul 2026 20:00:00 GMT` to `Mon, 06 Jul 2026 20:00:01 GMT` while keeping the same signature.	Reject
Missing covered component	Remove the `"@target-uri"` line from the signature base while keeping the same signature.	Reject
Algorithm substitution	Replace the `alg` value in `@signature-params` with either of the other two identifiers while keeping the same key and signature.	Reject
Wrong key	Verify the signature with the public key from any other vector.	Reject
Signature bit flip	Flip the low bit of the first signature byte.	Reject
Truncated signature	Remove the final signature byte.	Reject
Extended signature	Append one `0x00` byte to the signature.	Reject
Non-empty ML-DSA context	Invoke FIPS 204 verification with any non-empty context string.	Reject
Prehashed message	Invoke FIPS 204 verification on `SHA-256(signature base)` instead of the signature base itself.	Reject

IANA Considerations §

This document requests registration of the following values in the HTTP Signature Algorithms registry.

Algorithm Name	Description	Status	Reference
`ml-dsa-44`	ML-DSA-44 using FIPS 204	Active	`c2sp.org/httpsig-pq@v0.2.0`
`ml-dsa-65`	ML-DSA-65 using FIPS 204	Active	`c2sp.org/httpsig-pq@v0.2.0`
`ml-dsa-87`	ML-DSA-87 using FIPS 204	Active	`c2sp.org/httpsig-pq@v0.2.0`

Security Considerations §

Applications using these algorithms inherit the security considerations of RFC 9421, including signature replay, insufficient component coverage, and matching covered components to the target message.

ML-DSA signatures are substantially larger than pre-quantum signatures. HTTP implementations and intermediaries need to accept header field values large enough for the selected parameter set.

An application SHOULD support only the ML-DSA parameter set or sets it actually uses.

This document does not specify hybrid (a.k.a. composite) signature schemes. Applications that desire this functionality can use RFC 9421's support for multiple signatures on the same HTTP message. For example, sig1 can use ed25519 while sig2 uses ml-dsa-44. The signature bases will differ because each signature has its own @signature-params, but the underlying HTTP message can be the same. In such a setup, application profiles SHOULD specify which signature labels are required, and verifiers MUST NOT treat the presence of any one valid signature as satisfying such a policy unless that signature is sufficient under the application's policy.