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Network Working Group M. Cavage
Internet-Draft Joyent
Intended status: Standards Track M. Sporny
Expires: January 22, 2015 Digital Bazaar
July 21, 2014
Signing HTTP Messages
draft-cavage-http-signatures-03
Abstract
When communicating over the Internet using the HTTP protocol, it can
be desirable for a server or client to authenticate the sender of a
particular message. It can also be desirable to ensure that the
message was not tampered with during transit. This document
describes a way for servers and clients to simultaneously add
authentication and message integrity to HTTP messages by using a
digital signature.
Feedback
This specification is a part of the Web Payments [1] work. Feedback
related to this specification should be sent to public-
webpayments@w3.org [2].
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on January 22, 2015.
Copyright Notice
Copyright (c) 2014 IETF Trust and the persons identified as the
document authors. All rights reserved.
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This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Using Signatures in HTTP Requests . . . . . . . . . . . . 3
1.2. Using Signatures in HTTP Responses . . . . . . . . . . . 4
2. The Components of a Signature . . . . . . . . . . . . . . . . 4
2.1. Signature Parameters . . . . . . . . . . . . . . . . . . 4
2.1.1. keyId . . . . . . . . . . . . . . . . . . . . . . . . 4
2.1.2. algorithm . . . . . . . . . . . . . . . . . . . . . . 4
2.1.3. headers . . . . . . . . . . . . . . . . . . . . . . . 4
2.1.4. signature . . . . . . . . . . . . . . . . . . . . . . 5
2.2. Ambiguous Parameters . . . . . . . . . . . . . . . . . . 5
2.3. Signature String Construction . . . . . . . . . . . . . . 5
2.4. Creating a Signature . . . . . . . . . . . . . . . . . . 6
2.5. Verifying a Signature . . . . . . . . . . . . . . . . . . 6
3. The 'Signature' HTTP Authentication Scheme . . . . . . . . . 7
3.1. Authorization Header . . . . . . . . . . . . . . . . . . 7
3.1.1. Initiating Signature Authorization . . . . . . . . . 7
3.1.2. RSA Example . . . . . . . . . . . . . . . . . . . . . 8
3.1.3. HMAC Example . . . . . . . . . . . . . . . . . . . . 8
4. The 'Signature' HTTP Header . . . . . . . . . . . . . . . . . 9
4.1. Signature Header . . . . . . . . . . . . . . . . . . . . 9
4.1.1. RSA Example . . . . . . . . . . . . . . . . . . . . . 9
4.1.2. HMAC Example . . . . . . . . . . . . . . . . . . . . 10
5. References . . . . . . . . . . . . . . . . . . . . . . . . . 10
5.1. Normative References . . . . . . . . . . . . . . . . . . 10
5.2. Informative References . . . . . . . . . . . . . . . . . 11
5.3. URIs . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Appendix A. Security Considerations . . . . . . . . . . . . . . 12
Appendix B. Extensions . . . . . . . . . . . . . . . . . . . . . 12
Appendix C. Test Values . . . . . . . . . . . . . . . . . . . . 13
C.1. Default Test . . . . . . . . . . . . . . . . . . . . . . 13
C.2. Basic Test . . . . . . . . . . . . . . . . . . . . . . . 14
C.3. All Headers Test . . . . . . . . . . . . . . . . . . . . 14
Appendix D. Acknowledgements . . . . . . . . . . . . . . . . . . 15
Appendix E. IANA Considerations . . . . . . . . . . . . . . . . 15
E.1. Signature Authentication Scheme . . . . . . . . . . . . . 15
E.2. Signature Algorithm Registry . . . . . . . . . . . . . . 15
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 16
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1. Introduction
This protocol extension is intended to provide a simple and standard
way for clients to sign HTTP messages.
HTTP Authentication [RFC2617] defines Basic and Digest authentication
mechanisms, TLS 1.2 [RFC5246] defines cryptographically strong
transport layer security, and OAuth 2.0 [RFC6749] provides a fully-
specified alternative for authorization of web service requests.
Each of these approaches are employed on the Internet today with
varying degrees of protection. However, none of these schemes are
designed to cryptographically sign the HTTP messages themselves,
which is required in order to ensure end-to-end message integrity.
An added benefit of signing the HTTP message for the purposes of end-
to-end message integrity is that the client can be authenticated
using the same mechanism without the need for multiple round-trips.
Several web service providers have invented their own schemes for
signing HTTP messages, but to date, none have been standardized.
While there are no techniques in this proposal that are novel beyond
the previous art, it is useful to standardize a simple and
cryptographically strong mechanism for digitally signing HTTP
messages.
1.1. Using Signatures in HTTP Requests
It is common practice to protect sensitive website API functionality
via authentication mechanisms. Often, the entity accessing these
APIs is a piece of automated software outside of an interactive human
session. While there are mechanisms like OAuth and API secrets that
are used to grant API access, each have their weaknesses such as
unnecessary complexity for particular use cases or the use of shared
secrets which may not be acceptable to an implementer.
Digital signatures are widely used to provide authentication without
the need for shared secrets. They also do not require a round-trip
in order to authenticate the client. A server need only have a
mapping between the key being used to sign the content and the
authorized entity to verify that a message was signed by that entity.
This specification provides two mechanisms that can be used by a
server to authenticate a client. The first is the 'Signature' HTTP
Authentication Scheme, which may be used for interactive sessions.
The second is the Signature HTTP Header, which is typically used by
automated software agents.
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1.2. Using Signatures in HTTP Responses
For high security transactions, having an additional signature on the
HTTP header allows a client to ensure that even if the transport
channel has been compromised, that the content of the messages have
not been compromised. This specification provides a HTTP Signature
Header mechanism that can be used by a client to authenticate the
sender of a message and ensure that particular headers have not been
modified in transit.
2. The Components of a Signature
There are a number of components in a signature that are common
between the 'Signature' HTTP Authentication Scheme and the
'Signature' HTTP Header. This section details the components of a
digital signature.
2.1. Signature Parameters
The following section details the signature parameters.
2.1.1. keyId
REQUIRED. The `keyId` field is an opaque string that the server can
use to look up the component they need to validate the signature. It
could be an SSH key fingerprint, a URL to machine-readable key data,
an LDAP DN, etc. Management of keys and assignment of `keyId` is out
of scope for this document.
2.1.2. algorithm
REQUIRED. The `algorithm` parameter is used to specify the digital
signature algorithm to use when generating the signature. Valid
values for this parameter can be found in the Signature Algorithms
registry located at http://www.iana.org/assignments/signature-
algorithms and MUST NOT be marked "deprecated".
2.1.3. headers
OPTIONAL. The `headers` parameter is used to specify the list of
HTTP headers included when generating the signature for the message.
If specified, it should be a lowercased, quoted list of HTTP header
fields, separated by a single space character. If not specified,
implementations MUST operate as if the field were specified with a
single value, the `Date` header, in the list of HTTP headers. Note
that the list order is important, and MUST be specified in the order
the HTTP header field-value pairs are concatenated together during
signing.
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2.1.4. signature
REQUIRED. The `signature` parameter is a base 64 encoded digital
signature, as described in RFC 4648 [RFC4648], Section 4 [4]. The
client uses the `algorithm` and `headers` signature parameters to
form a canonicalized `signing string`. This `signing string` is then
signed with the key associated with `keyId` and the algorithm
corresponding to `algorithm`. The `signature` parameter is then set
to the base 64 encoding of the signature.
2.2. Ambiguous Parameters
If any of the parameters listed above are erroneously duplicated in
the associated header field, then the last parameter defined MUST be
used. Any parameter that is not recognized as a parameter, or is not
well-formed, MUST be ignored.
2.3. Signature String Construction
In order to generate the string that is signed with a key, the client
MUST use the values of each HTTP header field in the `headers`
Signature parameter, in the order they appear in the `headers`
Signature parameter. It is out of scope for this document to dictate
what header fields an application will want to enforce, but
implementers SHOULD at minimum include the request target and Date
header fields.
To include the HTTP request target in the signature calculation, use
the special `(request-target)` header field name.
1. If the header field name is `(request-target)` then generate the
header field value by concatenating the lowercased :method, an
ASCII space, and the :path pseudo-headers (as specified in
HTTP/2, Section 8.1.2.1 [5]).
2. Create the header field string by concatenating the lowercased
header field name followed with an ASCII colon `:`, an ASCII
space ` `, and the header field value. Leading and trailing
optional whitespace (OWS) in the header field value MUST be
omitted (as specified in RFC7230 [RFC7230], Section 3.2.4 [6]).
Any other modification to the header field value MUST NOT be
made. If there are multiple instances of the same header field,
all header field values associated with the header field MUST be
concatenated and used in the order in which they will appear in
the transmitted HTTP message.
3. If value is not the last value then append an ASCII newline `\n`.
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2.4. Creating a Signature
In order to create a signature, a client MUST:
1. Use the contents of the HTTP message, the `headers` value, and
the Signature String Construction algorithm to create the
signature string.
2. The `algorithm` and key associated with `keyId` must then be used
to generate a digital signature on the signature string.
3. The `signature` is then generated by base 64 encoding the output
of the digital signature algorithm.
For example, assume that the `algorithm` value was "rsa-sha256".
This would signal to the application that the data associated with
`keyId` is an RSA Private Key (as defined in RFC 3447 [RFC3447]), the
signature string hashing function is SHA-256, and the signing
algorithm is the one defined in RFC 3447 [RFC3447],
Section Section 8.2.1 [7]. The result of the signature creation
algorithm specified in RFC 3447 [RFC3447] should result in a binary
string, which is then base 64 encoded and placed into the `signature`
value.
2.5. Verifying a Signature
In order to verify a signature, a server MUST:
1. Use the received HTTP message, the `headers` value, and the
Signature String Construction algorithm to recreate the signature
string.
2. The `algorithm`, `keyId`, and base 64 decoded `signature` listed
in the signature parameters are then used to verify the
authenticity of the digital signature.
For example, assume that the `algorithm` value was "rsa-sha256".
This would signal to the application that the data associated with
`keyId` is an RSA Public Key (as defined in RFC 3447 [RFC3447]), the
signature string hashing function is SHA-256, and the `signature`
verification algorithm to use to verify the signature is the one
defined in RFC 3447 [RFC3447], Section Section 8.2.2 [8]. The result
of the signature verification algorithm specified in RFC 3447
[RFC3447] should result in a successful verification unless the
headers protected by the signature were tampered with in transit.
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3. The 'Signature' HTTP Authentication Scheme
The "signature" authentication scheme is based on the model that the
client must authenticate itself with a digital signature produced by
either a private asymmetric key (e.g., RSA) or a shared symmetric key
(e.g., HMAC). The scheme is parameterized enough such that it is not
bound to any particular key type or signing algorithm. However, it
does explicitly assume that clients can send an HTTP `Date` header.
3.1. Authorization Header
The client is expected to send an Authorization header (as defined in
RFC 7235 [RFC7235], Section 4.1 [9]) where the "auth-scheme" is
"Signature" and the "auth-param" parameters meet the requirements
listed in Section 2: The Components of a Signature.
The rest if this section uses the following HTTP request as an
example.
POST /foo HTTP/1.1
Host: example.org
Date: Tue, 07 Jun 2014 20:51:35 GMT
Content-Type: application/json
Digest: SHA-256=X48E9qOokqqrvdts8nOJRJN3OWDUoyWxBf7kbu9DBPE=
Content-Length: 18
{"hello": "world"}
Note that the use of the `Digest` header field is per RFC 3230
[RFC3230], Section 4.3.2 [10] and is included merely as a
demonstration of how an implementer could include information about
the body of the message in the signature. The following sections
also assume that the "rsa-key-1" keyId refers to a private key known
to the client and a public key known to the server. The "hmac-key-1"
keyId refers to key known to the client and server.
3.1.1. Initiating Signature Authorization
A server may notify a client when a protected resource could be
accessed by authenticating itself to the server. To initiate this
process, the server will request that the client authenticate itself
via a 401 response code. The server may optionally specify which
HTTP headers it expects to be signed by specifying the `headers`
parameter in the WWW-Authenticate header. For example:
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HTTP/1.1 401 Unauthorized
Date: Thu, 08 Jun 2014 18:32:30 GMT
Content-Length: 1234
Content-Type: text/html
WWW-Authenticate: Signature realm="Example",headers="(request-target) date"
...
3.1.2. RSA Example
The authorization header and signature would be generated as:
Authorization: Signature keyId="rsa-key-1",algorithm="rsa-sha256",
headers="(request-target) host date digest content-length",
signature="Base64(RSA-SHA256(signing string))"
The client would compose the signing string as:
(request-target): post /foo\n
host: example.org\n
date: Tue, 07 Jun 2014 20:51:35 GMT\n
digest: SHA-256=X48E9qOokqqrvdts8nOJRJN3OWDUoyWxBf7kbu9DBPE=\n
content-length: 18
Note that the '\n' symbols above are included to demonstrate where
the new line character should be inserted. There is no new line on
the final line of the signing string.
For an RSA-based signature, the authorization header and signature
would then be generated as:
Authorization: Signature keyId="rsa-key-1",algorithm="rsa-sha256",
headers="(request-target) host date digest content-length",
signature="Base64(RSA-SHA256(signing string))"
3.1.3. HMAC Example
For an HMAC-based signature without a list of headers specified, the
authorization header and signature would be generated as:
Authorization: Signature keyId="hmac-key-1",algorithm="hmac-sha256",
headers="(request-target) host date digest content-length",
signature="Base64(HMAC-SHA256(signing string))"
The only difference between the RSA Example and the HMAC Example is
the signature algorithm that is used. The client would compose the
signing string in the same way as the RSA Example above:
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(request-target): post /foo\n
host: example.org\n
date: Tue, 07 Jun 2014 20:51:35 GMT\n
digest: SHA-256=X48E9qOokqqrvdts8nOJRJN3OWDUoyWxBf7kbu9DBPE=\n
content-length: 18
4. The 'Signature' HTTP Header
The "signature" HTTP Header is based on the model that the sender
must authenticate itself with a digital signature produced by either
a private asymmetric key (e.g., RSA) or a shared symmetric key (e.g.,
HMAC). The scheme is parameterized enough such that it is not bound
to any particular key type or signing algorithm. However, it does
explicitly assume that senders can send an HTTP `Date` header.
4.1. Signature Header
The sender is expected to transmit a header (as defined in RFC 7230
[RFC7230], Section 3.2 [11]) where the "field-name" is "Signature",
and the "field-value" contains one or more "auth-param"s (as defined
in RFC 7235 [RFC7235], Section 4.1 [12]) where the "auth-param"
parameters meet the requirements listed in Section 2: The Components
of a Signature.
The rest if this section uses the following HTTP request as an
example.
POST /foo HTTP/1.1
Host: example.org
Date: Tue, 07 Jun 2014 20:51:35 GMT
Content-Type: application/json
Digest: SHA-256=X48E9qOokqqrvdts8nOJRJN3OWDUoyWxBf7kbu9DBPE=
Content-Length: 18
{"hello": "world"}
The following sections assume that the "rsa-key-1" keyId refers to a
private key known to the client and a public key known to the server.
The "hmac-key-1" keyId refers to key known to the client and server.
4.1.1. RSA Example
The signature header and signature would be generated as:
Signature: keyId="rsa-key-1",algorithm="rsa-sha256",
headers="(request-target) host date digest content-length",
signature="Base64(RSA-SHA256(signing string))"
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The client would compose the signing string as:
(request-target): post /foo\n
host: example.org\n
date: Tue, 07 Jun 2014 20:51:35 GMT\n
digest: SHA-256=X48E9qOokqqrvdts8nOJRJN3OWDUoyWxBf7kbu9DBPE=\n
content-length: 18
Note that the '\n' symbols above are included to demonstrate where
the new line character should be inserted. There is no new line on
the final line of the signing string.
For an RSA-based signature, the authorization header and signature
would then be generated as:
Signature: keyId="rsa-key-1",algorithm="rsa-sha256",
headers="(request-target) host date digest content-length",
signature="Base64(RSA-SHA256(signing string))"
4.1.2. HMAC Example
For an HMAC-based signature without a list of headers specified, the
authorization header and signature would be generated as:
Signature: keyId="hmac-key-1",algorithm="hmac-sha256",
headers="(request-target) host date digest content-length",
signature="Base64(HMAC-SHA256(signing string))"
The only difference between the RSA Example and the HMAC Example is
the signature algorithm that is used. The client would compose the
signing string in the same way as the RSA Example above:
(request-target): post /foo\n
host: example.org\n
date: Tue, 07 Jun 2014 20:51:35 GMT\n
digest: SHA-256=X48E9qOokqqrvdts8nOJRJN3OWDUoyWxBf7kbu9DBPE=\n
content-length: 18
5. References
5.1. Normative References
[I-D.ietf-jose-json-web-algorithms]
Jones, M., "JSON Web Algorithms (JWA)", draft-ietf-jose-
json-web-algorithms-20 (work in progress), January 2014.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
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[RFC4648] Josefsson, S., "The Base16, Base32, and Base64 Data
Encodings", RFC 4648, October 2006.
[RFC6376] Crocker, D., Hansen, T., and M. Kucherawy, "DomainKeys
Identified Mail (DKIM) Signatures", STD 76, RFC 6376,
September 2011.
[RFC7230] Fielding, R. and J. Reschke, "Hypertext Transfer Protocol
(HTTP/1.1): Message Syntax and Routing", RFC 7230, June
2014.
[RFC7235] Fielding, R. and J. Reschke, "Hypertext Transfer Protocol
(HTTP/1.1): Authentication", RFC 7235, June 2014.
5.2. Informative References
[RFC2617] Franks, J., Hallam-Baker, P., Hostetler, J., Lawrence, S.,
Leach, P., Luotonen, A., and L. Stewart, "HTTP
Authentication: Basic and Digest Access Authentication",
RFC 2617, June 1999.
[RFC3230] Mogul, J. and A. Van Hoff, "Instance Digests in HTTP", RFC
3230, January 2002.
[RFC3447] Jonsson, J. and B. Kaliski, "Public-Key Cryptography
Standards (PKCS) #1: RSA Cryptography Specifications
Version 2.1", RFC 3447, February 2003.
[RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer Security
(TLS) Protocol Version 1.2", RFC 5246, August 2008.
[RFC6749] Hardt, D., "The OAuth 2.0 Authorization Framework", RFC
6749, October 2012.
5.3. URIs
[2] http://tools.ietf.org/html/rfc4648#section-4
[3] http://tools.ietf.org/html/draft-ietf-httpbis-
http2-13#section-8.1.2.1
[4] http://tools.ietf.org/html/rfc7230#section-3.2.4
[5] http://tools.ietf.org/html/rfc3447#section-8.2.1
[6] http://tools.ietf.org/html/rfc3447#section-8.2.2
[7] http://tools.ietf.org/html/draft-ietf-rfc7235-auth-25#section-4.1
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[8] http://tools.ietf.org/html/rfc3230#section-4.3.2
[9] http://tools.ietf.org/html/rfc7230#section-3.2
[10] http://tools.ietf.org/html/rfc7235#section-4.1
[11] https://web-payments.org/specs/source/http-signatures-audit/
[12] https://web-payments.org/specs/source/http-signature-nonces/
[13] https://web-payments.org/specs/source/http-signature-trailers/
Appendix A. Security Considerations
There are a number of security considerations to take into account
when implementing or utilizing this specification. A thorough
security analysis of this protocol, including its strengths and
weaknesses, can be found in Security Considerations for HTTP
Signatures [13].
Appendix B. Extensions
This specification was designed to be simple, modular, and
extensible. There are a number of other specifications that build on
this one. For example, the HTTP Signature Nonces [14] specification
details how to use HTTP Signatures over a non-secured channel like
HTTP and the HTTP Signature Trailers [15] specification explains how
to apply HTTP Signatures to streaming content. Developers that
desire more functionality than this specification provides are urged
to ensure that an extension specification doesn't already exist
before implementing a proprietary extension.
If extensions to this specification are made by adding new Signature
Parameters, those extension parameters MUST be registered in the
Signature Authentication Scheme Registry. The registry will be
created and maintained at (the suggested URI) http://www.iana.org/
assignments/http-auth-scheme-signature . An example entry in this
registry is included below:
Signature Parameter: nonce
Reference to specification: [HTTP_AUTH_SIGNATURE_NONCE], Section XYZ.
Notes (optional): The HTTP Signature Nonces specification details
how to use HTTP Signatures over a unsecured channel like HTTP.
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Appendix C. Test Values
The following test data uses the following RSA 2048-bit keys, which
we will refer to as `keyId=Test` in the following samples:
-----BEGIN PUBLIC KEY-----
MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDCFENGw33yGihy92pDjZQhl0C3
6rPJj+CvfSC8+q28hxA161QFNUd13wuCTUcq0Qd2qsBe/2hFyc2DCJJg0h1L78+6
Z4UMR7EOcpfdUE9Hf3m/hs+FUR45uBJeDK1HSFHD8bHKD6kv8FPGfJTotc+2xjJw
oYi+1hqp1fIekaxsyQIDAQAB
-----END PUBLIC KEY-----
-----BEGIN RSA PRIVATE KEY-----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-----END RSA PRIVATE KEY-----
All examples use this request:
POST /foo?param=value&pet=dog HTTP/1.1
Host: example.com
Date: Thu, 05 Jan 2014 21:31:40 GMT
Content-Type: application/json
Digest: SHA-256=X48E9qOokqqrvdts8nOJRJN3OWDUoyWxBf7kbu9DBPE=
Content-Length: 18
{"hello": "world"}
C.1. Default Test
If a list of headers is not included, the date is the only header
that is signed by default. The string to sign would be:
date: Thu, 05 Jan 2014 21:31:40 GMT
The Authorization header would be:
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Authorization: Signature keyId="Test",algorithm="rsa-sha256",
signature="ATp0r26dbMIxOopqw0OfABDT7CKMIoENumuruOtarj8n/97Q3htH
FYpH8yOSQk3Z5zh8UxUym6FYTb5+A0Nz3NRsXJibnYi7brE/4tx5But9kkFGzG+
xpUmimN4c3TMN7OFH//+r8hBf7BT9/GmHDUVZT2JzWGLZES2xDOUuMtA="
The Signature header would be:
Signature: keyId="Test",algorithm="rsa-sha256",
signature="ATp0r26dbMIxOopqw0OfABDT7CKMIoENumuruOtarj8n/97Q3htH
FYpH8yOSQk3Z5zh8UxUym6FYTb5+A0Nz3NRsXJibnYi7brE/4tx5But9kkFGzG+
xpUmimN4c3TMN7OFH//+r8hBf7BT9/GmHDUVZT2JzWGLZES2xDOUuMtA="
C.2. Basic Test
The minimum recommended data to sign is the (request-target), host,
and date. In this case, the string to sign would be:
(request-target): post /foo?param=value&pet=dog
host: example.com
date: Thu, 05 Jan 2014 21:31:40 GMT
The Authorization header would be:
Authorization: Signature keyId="Test",algorithm="rsa-sha256",
headers="(request-target) host date", signature="KcLSABBj/m3v2Dhxi
CKJmzYJvnx74tDO1SaURD8Dr8XpugN5wpy8iBVJtpkHUIp4qBYpzx2QvD16t8X
0BUMiKc53Age+baQFWwb2iYYJzvuUL+krrl/Q7H6fPBADBsHqEZ7IE8rR0Ys3l
b7J5A6VB9J/4yVTRiBcxTypW/mpr5w="
C.3. All Headers Test
A strong signature including all of the headers and a digest of the
body of the HTTP request would result in the following signing
string:
(request-target): post /foo?param=value&pet=dog
host: example.com
date: Thu, 05 Jan 2014 21:31:40 GMT
content-type: application/json
digest: SHA-256=X48E9qOokqqrvdts8nOJRJN3OWDUoyWxBf7kbu9DBPE=
content-length: 18
The Authorization header would be:
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Authorization: Signature keyId="Test",algorithm="rsa-sha256",
headers="(request-target) host date content-type digest content-length",
signature="jgSqYK0yKclIHfF9zdApVEbDp5eqj8C4i4X76pE+XHoxugXv7q
nVrGR+30bmBgtpR39I4utq17s9ghz/2QFVxlnToYAvbSVZJ9ulLd1HQBugO0j
Oyn9sXOtcN7uNHBjqNCqUsnt0sw/cJA6B6nJZpyNqNyAXKdxZZItOuhIs78w="
The Signature header would be:
Signature: keyId="Test",algorithm="rsa-sha256",
headers="(request-target) host date content-type digest content-length",
signature="jgSqYK0yKclIHfF9zdApVEbDp5eqj8C4i4X76pE+XHoxugXv7q
nVrGR+30bmBgtpR39I4utq17s9ghz/2QFVxlnToYAvbSVZJ9ulLd1HQBugO0j
Oyn9sXOtcN7uNHBjqNCqUsnt0sw/cJA6B6nJZpyNqNyAXKdxZZItOuhIs78w="
Appendix D. Acknowledgements
The editor would like to thank the following individuals for feedback
on and implementations of the specification (in alphabetical order):
Stephen Farrell, Phillip Hallam-Baker, Dave Lehn, Dave Longley, James
H. Manger, Mark Nottingham, Yoav Nir, Julian Reschke, and Michael
Richardson.
Appendix E. IANA Considerations
E.1. Signature Authentication Scheme
The following entry should be added to the Authentication Scheme
Registry located at http://www.iana.org/assignments/http-authschemes
Authentication Scheme Name: Signature
Reference: [RFC_THIS_DOCUMENT], Section 2.
Notes (optional): The Signature scheme is designed for clients to
authenticate themselves with a server.
E.2. Signature Algorithm Registry
The following initial entries should be added to the Signature
Algorithm Registry to be created and maintained at (the suggested
URI) http://www.iana.org/assignments/signature-algorithms :
Editor's note: The references in this section are problematic as many
of the specifications that they refer to are too implementation
specific, rather than just pointing to the proper signature and
hashing specifications. A better approach might be just specifying
the signature and hashing function specifications, leaving
implementers to connect the dots (which are not that hard to
connect).
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Algorithm Name: rsa-sha1
Reference: RFC 6376 [RFC6376], Section 3.3.1
Status: deprecated
Algorithm Name: rsa-sha256
Reference: RFC 6376 [RFC6376], Section 3.3.2
Status: active
Algorithm Name: hmac-sha256
Reference: HS256 in JOSE JSON Web Algorithms
[I-D.ietf-jose-json-web-algorithms], Section 3.2
Status: active
Algorithm Name: ecdsa-sha256
Reference: ES256 in JOSE JSON Web Algorithms
[I-D.ietf-jose-json-web-algorithms], Section 3.4
Status: active
Authors' Addresses
Mark Cavage
Joyent
One Embarcadero Center
9th Floor
San Francisco, CA 94111
US
Phone: +1 415 400 0626
Email: mark.cavage@joyent.com
URI: http://www.joyent.com/
Manu Sporny
Digital Bazaar
1700 Kraft Drive
Suite 2408
Blacksburg, VA 24060
US
Phone: +1 540 961 4469
Email: msporny@digitalbazaar.com
URI: http://manu.sporny.org/
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