Network Working Group E. Hammer-Lahav
Internet-Draft Yahoo!
Intended status: Standards Track January 22, 2011
Expires: July 26, 2011
HTTP Authentication: MAC Authentication
draft-hammer-oauth-v2-mac-token-02
Abstract
This document specifies the HTTP MAC authentication scheme, as well
as its OAuth 2.0 binding.
Status of this Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
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This Internet-Draft will expire on July 26, 2011.
Copyright Notice
Copyright (c) 2011 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
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the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Example . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.2. Notational Conventions . . . . . . . . . . . . . . . . . . 5
2. Issuing MAC Credentials . . . . . . . . . . . . . . . . . . . 5
3. Making Requests . . . . . . . . . . . . . . . . . . . . . . . 5
3.1. The "Authorization" Request Header . . . . . . . . . . . . 6
3.2. Body Hash . . . . . . . . . . . . . . . . . . . . . . . . 7
3.3. Signature . . . . . . . . . . . . . . . . . . . . . . . . 8
3.3.1. Normalized Request String . . . . . . . . . . . . . . 9
3.3.2. hmac-sha-1 . . . . . . . . . . . . . . . . . . . . . . 12
3.3.3. hmac-sha-256 . . . . . . . . . . . . . . . . . . . . . 13
4. Verifying Requests . . . . . . . . . . . . . . . . . . . . . . 13
4.1. The "WWW-Authenticate" Response Header Field . . . . . . . 14
5. Scheme Extensions . . . . . . . . . . . . . . . . . . . . . . 15
6. Use with OAuth 2.0 . . . . . . . . . . . . . . . . . . . . . . 15
6.1. Issuing MAC-Type Access Tokens . . . . . . . . . . . . . . 15
7. Security Considerations . . . . . . . . . . . . . . . . . . . 16
7.1. Secrets Transmission . . . . . . . . . . . . . . . . . . . 16
7.2. Confidentiality of Requests . . . . . . . . . . . . . . . 16
7.3. Spoofing by Counterfeit Servers . . . . . . . . . . . . . 16
7.4. Plaintext Storage of Credentials . . . . . . . . . . . . . 16
7.5. Entropy of Secrets . . . . . . . . . . . . . . . . . . . . 17
7.6. Denial of Service / Resource Exhaustion Attacks . . . . . 17
7.7. Coverage Limitations . . . . . . . . . . . . . . . . . . . 18
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 18
8.1. OAuth Access Token Type Registration . . . . . . . . . . . 18
8.1.1. The "mac" OAuth Access Token Type . . . . . . . . . . 18
8.2. OAuth Parameters Registration . . . . . . . . . . . . . . 18
8.2.1. The "secret" OAuth Parameter . . . . . . . . . . . . . 19
8.2.2. The "algorithm" OAuth Parameter . . . . . . . . . . . 19
9. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 19
Appendix A. Document History . . . . . . . . . . . . . . . . . . 19
10. References . . . . . . . . . . . . . . . . . . . . . . . . . . 20
10.1. Normative References . . . . . . . . . . . . . . . . . . . 20
10.2. Informative References . . . . . . . . . . . . . . . . . . 21
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 21
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1. Introduction
This specification defines the HTTP MAC authentication scheme and
provides a method for making authenticated HTTP requests with partial
cryptographic verification of the request - covering the HTTP method,
request URI, host, and in some cases the request body.
This specification uses the terminology defined in
[I-D.ietf-oauth-v2].
Please discuss this draft on the oauth@ietf.org [1] mailing list.
1.1. Example
The client attempts to access a protected resource without
authentication, making the following HTTP request to the resource
server:
GET /resource/1?b=1&a=2 HTTP/1.1
Host: example.com
The resource server returns the following authentication challenge:
HTTP/1.1 401 Unauthorized
WWW-Authenticate: MAC realm="example"
Date: Thu, 02 Dec 2010 21:39:45 GMT
The client has previously obtained a set of token credentials for
accessing resources on the "http://example.com/" resource server.
The MAC credentials issued to the client included the following
attributes:
Access Token: h480djs93hd8
Token secret: 489dks293j39
MAC algorithm: hmac-sha-1
The client attempts the HTTP request again, this time using the token
credentials issued earlier to authenticate. To construct the
authentication header, the client calculates the current timestamp
and generates a nonce. The nonce is unique to the timestamp used,
typically a random string:
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Timestamp: 137131200
Nonce: dj83hs9s
The client normalizes the request and constructs the normalized
request string (the new line separator character is represented by
"\n" for display purposes only):
h480djs93hd8\n
137131200\n
dj83hs9s\n
\n
GET\n
example.com\n
80\n
/resource/1\n
a=2\n
b=1\n
The normalized request string is signed using the specified MAC
algorithm "hmac-sha-1" with the normalized request string as text and
the token secret as key. The resulting digest is base64-encoded to
produce the request signature:
YTVjyNSujYs1WsDurFnvFi4JK6o=
The client includes the access token, timestamp, nonce, and signature
with the request using the "Authorization" request header field:
GET /resource/1 HTTP/1.1
Host: example.com
Authorization: MAC token="h480djs93hd8",
timestamp="137131200",
nonce="dj83hs9s",
signature="YTVjyNSujYs1WsDurFnvFi4JK6o="
The resource server validates the request by calculating the
signature again based on the request received and verifies the
validity and scope of the access token. If valid, the resource
server responds with the requested protected resource representation.
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1.2. Notational Conventions
The key words 'MUST', 'MUST NOT', 'REQUIRED', 'SHALL', 'SHALL NOT',
'SHOULD', 'SHOULD NOT', 'RECOMMENDED', 'MAY', and 'OPTIONAL' in this
specification are to be interpreted as described in [RFC2119].
This specification uses the Augmented Backus-Naur Form (ABNF)
notation of [I-D.ietf-httpbis-p1-messaging]. Additionally, the
following rules are included from [RFC2617]: realm, auth-param.
2. Issuing MAC Credentials
This specification does not define a general purpose method for
requesting or issuing MAC credentials (an OAuth 2.0
[I-D.ietf-oauth-v2] binding is provided in Section 6). It simply
assumes that the client is in the possession of a set of MAC
credentials with the following REQUIRES attributes:
access token
A string representing an access authorization issued to the
client. The string is usually opaque to the client. Tokens
represent specific scopes and durations of access. The token
may denote an identifier used to retrieve the authorization
information, or self-contain the authorization information in a
verifiable manner (i.e. a token string consisting of some data
and a signature).
secret
A shared symmetric secret used as the MAC algorithm key.
algorithm
A MAC algorithm used to calculate the request signature. Value
MUST be one of "hmac-sha-1", "hmac-sha-256", or a registered
extension algorithm name as described in Section 5.
The access token and secret strings MUST NOT include characters other
than:
DIGIT / ALPHA / %x20-21 / %x23-5B / %x5D-7E
; Any printable ASCII character except for <"> and <\>
3. Making Requests
To make authenticated requests, the client must be in possession of a
valid set of MAC credentials accepted by the resource server. The
client constructs the request by calculating of a set of attributes,
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and adding them to the HTTP request using the Authorization header
field (Section 3.1). Authenticated requests can be sent in response
to an authentication challenge or directly.
3.1. The "Authorization" Request Header
The "Authorization" request header field uses the framework defined
by [RFC2617] as follows:
credentials = 'MAC' [ RWS 1#param ]
param = access-token /
timestamp /
nonce /
body-hash /
signature
access-token = 'token' '=' <"> plain-string <">
timestamp = 'timestamp' '=' <"> 1*DIGIT <">
nonce = 'nonce' '=' <"> plain-string <">
body-hash = 'bodyhash' '=' <"> plain-string <">
signature = 'signature' '=' <"> plain-string <">
plain-string = 1*( DIGIT / ALPHA / %x20-21 / %x23-5B / %x5D-7E )
The header attributes are defined as follows:
token
REQUIRED. The access token string.
timestamp
REQUIRED. The current time expressed in the number of seconds
since January 1, 1970 00:00:00 GMT, and MUST be a positive
integer.
nonce
REQUIRED. A random string, uniquely generated by the client to
allow the resource server to verify that a request has never
been made before and helps prevent replay attacks when requests
are made over an insecure channel. The nonce value MUST be
unique across all requests with the same timestamp and access
token combination.
To avoid the need to retain an infinite number of nonce values
for future checks, resource servers MAY choose to restrict the
time period after which a request with an old timestamp is
rejected. Such a restriction implies a level of
synchronization between the client's and server's clocks. The
client MAY use the "Date" response header field to synchronize
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its clock after a failed request.
bodyhash
OPTIONAL. The HTTP request entity-body hash as described in
Section 3.2.
signature
REQUIRED. The HTTP request signature as described in
Section 3.3.
Attributes MUST NOT appear more than once. Attribute values are
limited to a subset of ASCII, which does not require escaping, as
defined by the plain-string ABNF.
3.2. Body Hash
The body hash is used to provide integrity verification of the HTTP
request entity-body. The hash value is calculated using a hash
algorithm over the entire HTTP request entity-body as included in the
request.
The client MAY include the body hash with any request. The server
SHOULD require the calculation and inclusion of the body hash with
any request containing an entity-body, or when the presence (or lack
of) of an entity-body matters.
The body hash algorithm is determined by the access token algorithm
provided with the access token. The SHA-1 hash algorithm as defined
by [NIST FIPS-180-3] is used with the "hmac-sha-1" access token
algorithm. The SHA-256 hash algorithm as defined by [NIST
FIPS-180-3] is used with the "hmac-sha-256" access token algorithm.
Additional access token algorithms MUST specify the body hash
algorithm.
The body hash is calculated as follows:
bodyhash = BASE64 ( HASH (text) )
Where:
HASH
is the hash algorithm function,
text
is the HTTP request entity-body,
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BASE64
is the base64-encoding function per [RFC2045] section 6.8,
applied to the hash digest result octet string, and
bodyhash
is the value used in the normalized request string and to set
the "bodyhash" attribute of the "Authorization" header field.
The body hash is calculated before the normalized request string is
constructed and the signature is calculated.
For example, the HTTP request:
POST /request HTTP/1.1
Host: example.com
Content-Type: application/x-www-form-urlencoded
hello=world%21
using access token "j92fsdjf094gjfdi", timestamp "137131206", nonce
"f403hksd", access token algorithm "hmac-sha-1", and secret
"8yfrufh348h", is transmitted as (line breaks are for display
purposes only):
POST /request HTTP/1.1
Host: example.com
Content-Type: application/x-www-form-urlencoded
Authorization: MAC token="h480djs93hd8",
timestamp="137131200",
nonce="dj83hs9s",
bodyhash="k9kbtCIy0CkI3/FEfpS/oIDjk6k=",
signature="FR1UCL6Ny6bsx8EkKkiveFYv5VU="
hello=world%21
3.3. Signature
The client uses the MAC algorithm and the token secret to calculate
the request signature. This specification defines two algorithms:
"hmac-sha-1" and "hmac-sha-256", and provides an extension registry
for additional algorithms.
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3.3.1. Normalized Request String
The normalized request string is a consistent, reproducible
concatenation of several of the HTTP request elements into a single
string. By normalizing the request into a reproducible string, the
client and resource server can both sign the same string.
The string is constructed by concatenating together, in order, the
following HTTP request elements, each followed by a new line
character (%x0A):
1. The access token.
2. The timestamp value calculated for the request.
3. The nonce value generated for the request.
4. The request entity-body hash as described in Section 3.2 if one
was calculated and included in the request, otherwise, an empty
string. Note that the body hash of an empty entity-body is
typically not an empty string.
5. The HTTP request method in upper case. For example: "HEAD",
"GET", "POST", etc.
6. The hostname included in the HTTP request using the "Host"
request header field in lower case.
7. The port as included in the HTTP request using the "Host" request
header field. If the header field does not include a port, the
default value for the scheme MUST be used (e.g. 80 for HTTP and
443 for HTTPS).
8. The path component of the HTTP request URI as defined by
[RFC3986] section 3.3.
9. The query component of the HTTP request URI as defined by
[RFC3986] section 3.4, normalized as described in
Section 3.3.1.1.
[[ TODO: I18N ]]
For example, the HTTP request:
POST /request?b5=%3D%253D&a3=a&c%40=&a2=r%20b&c2&a3=2+q HTTP/1.1
Host: example.com
Hello World!
using access token "kkk9d7dh3k39sjv7", timestamp "137131201", nonce
"7d8f3e4a", and body hash "Lve95gjOVATpfV8EL5X4nxwjKHE=" is
normalized into the following string (the new line separator
character is represented by "\n" for display purposes only):
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kkk9d7dh3k39sjv7\n
137131201\n
7d8f3e4a\n
Lve95gjOVATpfV8EL5X4nxwjKHE=\n
POST\n
example.com\n
80\n
/request\n
a2=r%20b\n
a3=2%20q\n
a3=a\n
b5=%3D%253D\n
c%40=\n
c2=\n
3.3.1.1. Parameters Normalization
The query component is parsed into a list of name/value parameter
pairs by treating it as an "application/x-www-form-urlencoded"
string, separating the names and values and decoding them as defined
by [W3C.REC-html401-19991224] section 17.13.4. Form-encoded
parameters present in the entity-body are not included.
Once separated and decoded, the parameters are concatenated back
together as follows:
1. First, the name and value of each parameter are escaped using the
[RFC3986] percent-encoding (%XX) mechanism. Characters in the
unreserved character set as defined by [RFC3986] section 2.3
(ALPHA, DIGIT, "-", ".", "_", "~") MUST NOT be encoded. All
other characters MUST be encoded. The two hexadecimal characters
used to represent encoded characters MUST be upper case.
2. The name of each parameter is concatenated to its corresponding
value using an "=" character (ASCII code 61) as separator, even
if the value is empty.
3. The name/value parameter pairs are sorted using ascending byte
value ordering.
4. The sorted parameters are concatenated together into a single
string by using an new line character (ASCII code 10) as
separator.
Note that the percent-encoding method described is different from the
encoding scheme used by the "application/x-www-form-urlencoded"
content-type (for example, it encodes space characters as "%20"
instead of the "+" character). It MAY be different from the percent-
encoding functions provided by web development frameworks (e.g.
encode different characters, use lower case hexadecimal characters).
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For example, the HTTP request URI:
/request?b5=%3D%253D&a3=a&c%40=&a2=r%20b&c2&a3=2+q
Contains the following (fully decoded) parameters used in the
normalized request sting:
+------+-------+
| Name | Value |
+------+-------+
| b5 | =%3D |
| a3 | a |
| c@ | |
| a2 | r b |
| c2 | |
| a3 | 2 q |
+------+-------+
Note that the value of "b5" is "=%3D" and not "==". Both "c@" and
"c2" have empty values. While the encoding rules specified in this
specification for the purpose of constructing the normalized request
string exclude the use of a "+" character (ASCII code 43) to
represent an encoded space character (ASCII code 32), this practice
is widely used in "application/x-www-form-urlencoded" encoded values,
and MUST be properly decoded, as demonstrated by one of the "a3"
parameter instances (the "a3" parameter is used twice in this
request).
The parsed parameters are normalized as follows:
Escaped:
+------+----------+
| Name | Value |
+------+----------+
| b5 | %3D%253D |
| a3 | a |
| c%40 | |
| a2 | r%20b |
| c2 | |
| a3 | 2%20q |
+------+----------+
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Concatenated Pairs:
+-------------+
| Name=Value |
+-------------+
| b5=%3D%253D |
| a3=a |
| c%40= |
| a2=r%20b |
| c2= |
| a3=2%20q |
+-------------+
Sorted:
+-------------+
| Name=Value |
+-------------+
| a2=r%20b |
| a3=2%20q |
| a3=a |
| b5=%3D%253D |
| c%40= |
| c2= |
+-------------+
And concatenated together into a single string (the new line
separator character is represented by "\n" for display purposes
only):
a2=r%20b\n
a3=2%20q\n
a3=a\n
b5=%3D%253D\n
c%40=\n
c2=\n
3.3.2. hmac-sha-1
"hmac-sha-1" uses the HMAC-SHA1 algorithm as defined in [RFC2104]:
digest = HMAC-SHA1 (key, text)
Where:
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text
is set to the value of the normalize request string as
described in Section 3.3.1,
key
is set to the access token shared-secret provided by the
authorization server, and
digest
is used to set the value of the "signature" attribute, after
the result octet string is base64-encoded per [RFC2045] section
6.8.
3.3.3. hmac-sha-256
"hmac-sha-1" uses the HMAC algorithm as defined in [RFC2104] together
with the SHA-256 hash function defined in [NIST FIPS-180-3]:
digest = HMAC-SHA256 (key, text)
Where:
text
is set to the value of the normalize request string as
described in Section 3.3.1,
key
is set to the access token shared-secret provided by the
authorization server, and
digest
is used to set the value of the "signature" attribute, after
the result octet string is base64-encoded per [RFC2045] section
6.8.
4. Verifying Requests
A servers receiving an authenticated request validates it by
performing the following REQUIRED steps:
1. Recalculate the request body hash (if included in the request) as
described in Section 3.2 and signature as described in
Section 3.3 and compare the signature to the value received from
the client via the "signature" attribute.
2. Ensure that the combination of nonce, timestamp, and access token
received from the client has not been used before in a previous
request (the server MAY reject requests with stale timestamps;
the determination of staleness is left up to the server to
define).
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3. Verify the scope and status of the access token.
If the request fails verification, the server SHOULD respond with an
HTTP 401 (unauthorized) status code, and SHOULD include a token
scheme authentication challenge using the WWW-Authenticate header
field. The server MAY include further details about why the request
was rejected using the error attribute.
4.1. The "WWW-Authenticate" Response Header Field
If the protected resource request does not include authentication
credentials, contains an invalid access token, or is malformed, the
resource server MUST include the HTTP "WWW-Authenticate" response
header field. The "WWW-Authenticate" header field uses the framework
defined by [RFC2617] as follows:
challenge = "MAC" [ RWS 1#param ]
param = realm / error / auth-param
error = "error" "=" quoted-string
Each attribute MUST NOT appear more than once.
If the protected resource request included a MAC "Authorization"
header field and failed authentication, the resource server MAY
include the "error" attribute to provide the client with a human-
readable explanation why the access request was declined.
For example, in response to a protected resource request without
authentication:
HTTP/1.1 401 Unauthorized
WWW-Authenticate: MAC realm="example"
And in response to a protected resource request with an
authentication attempt using an expired access token:
HTTP/1.1 401 Unauthorized
WWW-Authenticate: MAC realm="example"
error="The access token expired"
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The resource server response SHOULD use the appropriate HTTP status
code as follows:
400 (Bad Request)
The request is missing a required parameter, includes an
unsupported parameter or parameter value, repeats the same
parameter, uses more than one method for including an access
token, or is otherwise malformed.
401 (Unauthorized)
The access token provided is expired, revoked, malformed, or
invalid. The body hash or signature provided do not match the
values calculated by the server.
403 (Forbidden)
The request requires higher privileges than provided by the
access token.
5. Scheme Extensions
[[ TBD ]]
6. Use with OAuth 2.0
OAuth 2.0 ([I-D.ietf-oauth-v2]) defines a token-based authentication
framework in which third-party applications (clients) access
protected resources using access tokens. Access tokens are obtained
via the resource owners' authorization from an authorization server.
This specification defines the OAuth 2.0 MAC token type, as well as
type-specific token attributes.
This specification does not define methods for the client to
specifically request a MAC-type token from the authorization server.
Additionally, it does not include any discovery facilities for
identifying which HMAC algorithms are supported by a resource server,
or how the client may go about obtaining MAC access tokens.
6.1. Issuing MAC-Type Access Tokens
Authorization servers issuing MAC-type access tokens MUST include the
following parameters whenever a response includes the "access_token"
parameter:
secret
REQUIRED. The token shared secret used as the MAC algorithm
key.
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algorithm
REQUIRED. The MAC algorithm used to calculate the request
signature. Value MUST be one of "hmac-sha-1", "hmac-sha-256",
or a registered extension algorithm name as described in
Section 5.
7. Security Considerations
As stated in [RFC2617], the greatest sources of risks are usually
found not in the core protocol itself but in policies and procedures
surrounding its use. Implementers are strongly encouraged to assess
how this protocol addresses their security requirements.
7.1. Secrets Transmission
This specification does not describe any mechanism for obtaining or
transmitting access token secrets. Methods used to obtain tokens
should ensure that these transmissions are protected using transport-
layer mechanisms such as TLS or SSL.
7.2. Confidentiality of Requests
While this protocol provides a mechanism for verifying the integrity
of requests, it provides no guarantee of request confidentiality.
Unless further precautions are taken, eavesdroppers will have full
access to request content. Servers should carefully consider the
kinds of data likely to be sent as part of such requests, and should
employ transport-layer security mechanisms to protect sensitive
resources.
7.3. Spoofing by Counterfeit Servers
This protocol makes no attempt to verify the authenticity of the
resource server. A hostile party could take advantage of this by
intercepting the client's requests and returning misleading or
otherwise incorrect responses. Service providers should consider
such attacks when developing services using this protocol, and should
require transport-layer security for any requests where the
authenticity of the resource server or of request responses is an
issue.
7.4. Plaintext Storage of Credentials
The access token shared-secret functions the same way passwords do in
traditional authentication systems. In order to compute the
signature, the server must have access to the secret in plaintext
form. This is in contrast, for example, to modern operating systems,
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which store only a one-way hash of user credentials.
If an attacker were to gain access to these secrets - or worse, to
the server's database of all such secrets - he or she would be able
to perform any action on behalf of any resource owner. Accordingly,
it is critical that servers protect these secrets from unauthorized
access.
7.5. Entropy of Secrets
Unless a transport-layer security protocol is used, eavesdroppers
will have full access to authenticated requests and signatures, and
will thus be able to mount offline brute-force attacks to recover the
secret used. Authorization servers should be careful to assign
shared-secrets which are long enough, and random enough, to resist
such attacks for at least the length of time that the shared-secrets
are valid.
For example, if shared-secrets are valid for two weeks, authorization
servers should ensure that it is not possible to mount a brute force
attack that recovers the shared-secret in less than two weeks. Of
course, authorization servers are urged to err on the side of
caution, and use the longest secrets reasonable.
It is equally important that the pseudo-random number generator
(PRNG) used to generate these secrets be of sufficiently high
quality. Many PRNG implementations generate number sequences that
may appear to be random, but which nevertheless exhibit patterns or
other weaknesses which make cryptanalysis or brute force attacks
easier. Implementers should be careful to use cryptographically
secure PRNGs to avoid these problems.
7.6. Denial of Service / Resource Exhaustion Attacks
This specification includes a number of features which may make
resource exhaustion attacks against servers possible. For example,
this protocol requires servers to track used nonces. If an attacker
is able to use many nonces quickly, the resources required to track
them may exhaust available capacity. And again, this protocol can
require servers to perform potentially expensive computations in
order to verify the signature on incoming requests. An attacker may
exploit this to perform a denial of service attack by sending a large
number of invalid requests to the server.
Resource Exhaustion attacks are by no means specific to this
specification. However, implementers should be careful to consider
the additional avenues of attack that this protocol exposes, and
design their implementations accordingly. For example, entropy
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starvation typically results in either a complete denial of service
while the system waits for new entropy or else in weak (easily
guessable) secrets. When implementing this protocol, servers should
consider which of these presents a more serious risk for their
application and design accordingly.
7.7. Coverage Limitations
The normalized request string has been designed to support the
authentication methods defined in this specification. Those
designing additional methods, should evaluated the compatibility of
the normalized request string with their security requirements.
Since the normalized request string does not cover the entire HTTP
request, servers should employ additional mechanisms to protect such
elements.
The signature does not cover entity-header fields which can often
affect how the request body is interpreted by the server (i.e.
Content-Type). If the server behavior is influenced by the presence
or value of such header fields, an attacker can manipulate the
request header without being detected. This will alter the request
even when using the body hash attribute.
8. IANA Considerations
8.1. OAuth Access Token Type Registration
This specification registers the following access token type in the
OAuth Access Token Type Registry.
8.1.1. The "mac" OAuth Access Token Type
Type name:
mac
Additional Token Endpoint Response Parameters:
secret, algorithm
HTTP Authentication Scheme(s):
MAC
Change controller:
IETF
Specification document(s):
[[ this document ]]
8.2. OAuth Parameters Registration
This specification registers the following parameters in the OAuth
Parameters Registry established by [I-D.ietf-oauth-v2].
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8.2.1. The "secret" OAuth Parameter
Parameter name: secret
Parameter usage location: authorization response, token response
Change controller: IETF
Specification document(s): [[ this document ]]
Related information: None
8.2.2. The "algorithm" OAuth Parameter
Parameter name: algorithm
Parameter usage location: authorization response, token response
Change controller: IETF
Specification document(s): [[ this document ]]
Related information: None
9. Acknowledgments
The author would like to thank James Manger for his suggestions,
feedback, and continued support.
Appendix A. Document History
[[ To be removed by the RFC editor before publication as an RFC. ]]
-02
o Added body-hash support.
o Updated OAuth 2.0 reference and added token type registration
template.
o Removed error codes and error URI.
-01
o Changed parameters sorting to come after name=value string
construction.
o Added new line at the end of the normalized request string.
o Moved OAuth2 references to separate section.
o Added 'WWW-Authenticate' header definition.
o Fixed example header use of single quote.
o Restricted strings to ASCII subset (printable, no double-quotes or
back-slash).
-00
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o Initial draft.
10. References
10.1. Normative References
[I-D.ietf-httpbis-p1-messaging]
Fielding, R., Gettys, J., Mogul, J., Nielsen, H.,
Masinter, L., Leach, P., Berners-Lee, T., and J. Reschke,
"HTTP/1.1, part 1: URIs, Connections, and Message
Parsing", draft-ietf-httpbis-p1-messaging-08 (work in
progress), October 2009.
[I-D.ietf-oauth-v2]
Hammer-Lahav, E., Recordon, D., and D. Hardt, "The OAuth
2.0 Authorization Protocol", draft-ietf-oauth-v2-12 (work
in progress), January 2011.
[NIST FIPS-180-3]
National Institute of Standards and Technology, "Secure
Hash Standard (SHS). FIPS PUB 180-3, October 2008".
[RFC2045] Freed, N. and N. Borenstein, "Multipurpose Internet Mail
Extensions (MIME) Part One: Format of Internet Message
Bodies", RFC 2045, November 1996.
[RFC2104] Krawczyk, H., Bellare, M., and R. Canetti, "HMAC: Keyed-
Hashing for Message Authentication", RFC 2104,
February 1997.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[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.
[RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
Resource Identifier (URI): Generic Syntax", STD 66,
RFC 3986, January 2005.
[W3C.REC-html401-19991224]
Hors, A., Raggett, D., and I. Jacobs, "HTML 4.01
Specification", World Wide Web Consortium
Recommendation REC-html401-19991224, December 1999,
<http://www.w3.org/TR/1999/REC-html401-19991224>.
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10.2. Informative References
[RFC5849] Hammer-Lahav, E., "The OAuth 1.0 Protocol", RFC 5849,
April 2010.
URIs
[1] <https://www.ietf.org/mailman/listinfo/oauth>
Author's Address
Eran Hammer-Lahav
Yahoo!
Email: eran@hueniverse.com
URI: http://hueniverse.com
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