1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
|
;; webid-oidc, implementation of the Solid specification
;; Copyright (C) 2020, 2021 Vivien Kraus
;; This program is free software: you can redistribute it and/or modify
;; it under the terms of the GNU Affero General Public License as
;; published by the Free Software Foundation, either version 3 of the
;; License, or (at your option) any later version.
;; This program is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
;; GNU Affero General Public License for more details.
;; You should have received a copy of the GNU Affero General Public License
;; along with this program. If not, see <https://www.gnu.org/licenses/>.
(define-module (webid-oidc token-endpoint)
#:use-module (webid-oidc errors)
#:use-module (webid-oidc authorization-code)
#:use-module (webid-oidc dpop-proof)
#:use-module (webid-oidc jws)
#:use-module (webid-oidc jwk)
#:use-module (webid-oidc oidc-id-token)
#:use-module (webid-oidc access-token)
#:use-module ((webid-oidc stubs) #:prefix stubs:)
#:use-module ((webid-oidc refresh-token) #:prefix refresh:)
#:use-module (web client)
#:use-module (web request)
#:use-module (web response)
#:use-module (web uri)
#:use-module (ice-9 optargs)
#:use-module (ice-9 receive)
#:use-module (ice-9 control)
#:use-module (srfi srfi-19)
#:use-module (rnrs bytevectors))
(define (try-handle-web-failure thunk)
(define (error->str err)
(if (record? err)
(let* ((type (record-type-descriptor err))
(get
(lambda (slot)
((record-accessor type slot) err)))
(recurse
(lambda (err)
(error->str err))))
(case (record-type-name type)
((&cannot-decode-dpop-proof)
(format #f "the DPoP proof is invalid"))
((&no-authorization-code)
(format #f "there is no authorization code in the request"))
((&no-refresh-token)
(format #f "there is no refresh token in the request"))
((&cannot-decode-authorization-code)
(format #f "the authorization code is invalid"))
((&invalid-refresh-token)
(format #f "the refresh token is invalid"))
((&invalid-key-for-refresh-token)
(format #f "the refresh token is bound to another key"))
((&unsupported-grant-type)
(format #f "the grant type ~s is not supported" (get 'value)))
(else
(raise-exception err))))
(throw err)))
(call/ec
(lambda (return)
(with-exception-handler
(lambda (error)
(return
(build-response
#:code 400
#:reason-phrase (string-append "Bad Request: " (error->str error)))
(error->str error)
#f
error))
thunk
#:unwind? #t))))
(define*-public (make-token-endpoint token-endpoint-uri iss alg jwk validity jti-list
#:key
(refresh-token-dir refresh:default-dir)
(current-time current-time))
(lambda* (request request-body)
(try-handle-web-failure
(lambda ()
(when (bytevector? request-body)
(set! request-body (utf8->string request-body)))
(let ((current-time
(let ((t current-time))
(when (thunk? t)
(set! t (t)))
(when (integer? t)
(set! t (make-time time-utc 0 t)))
(when (time? t)
(set! t (time-utc->date t)))
t))
(form-args
(if (and (request-content-type request)
(eq? (car (request-content-type request))
'application/x-www-form-urlencoded))
(filter
(lambda (x) x)
(map (lambda (kv)
(let ((parsed
(list->vector
(map (lambda (x)
(uri-decode x #:decode-plus-to-space? #t))
(string-split kv #\=)))))
(if (eq? (vector-length parsed) 2)
`(,(vector-ref parsed 0) . ,(vector-ref parsed 1))
#f)))
(string-split request-body #\&)))
'()))
(method (request-method request))
;; Maybe we’re behind a reverse proxy, so the authority of
;; (request-uri request) is meaningless.
(uri (build-uri (uri-scheme token-endpoint-uri)
#:userinfo (uri-userinfo token-endpoint-uri)
#:host (uri-host token-endpoint-uri)
#:port (uri-port token-endpoint-uri)
#:path (uri-path (request-uri request))
#:query (uri-query (request-uri request)))))
(let ((grant-type (assoc-ref form-args "grant_type"))
(dpop (dpop-proof-decode
current-time jti-list method uri
(assq-ref (request-headers request) 'dpop)
(lambda (jkt) #t))))
(unless (and grant-type (string? grant-type))
(raise-unsupported-grant-type #f))
(receive (webid client-id)
(case (string->symbol grant-type)
((authorization_code)
(let ((code
(let ((str (assoc-ref form-args "code")))
(unless str
(raise-no-authorization-code))
(authorization-code-decode
current-time jti-list str jwk))))
(values (authorization-code-webid code)
(authorization-code-client-id code))))
((refresh_token)
(let ((refresh-token (assoc-ref form-args "refresh_token")))
(unless refresh-token
(raise-no-refresh-token))
(refresh:with-refresh-token
refresh-token
(dpop-proof-jwk dpop)
values
#:dir refresh-token-dir)))
(else
(raise-unsupported-grant-type grant-type)))
(let* ((iat (time-second (date->time-utc current-time)))
(exp (+ iat validity)))
(let ((id-token
(issue-id-token
jwk
#:alg alg
#:webid (uri->string webid)
#:sub (uri->string webid)
#:iss (uri->string iss)
#:aud (uri->string client-id)
#:exp exp
#:iat iat))
(access-token
(issue-access-token
jwk
#:alg alg
#:webid (uri->string webid)
#:iss (uri->string iss)
#:exp exp
#:iat iat
#:client-key (dpop-proof-jwk dpop)
#:client-id (uri->string client-id)))
(refresh-token
(if (equal? grant-type "refresh_token")
(assoc-ref form-args "refresh_token")
(refresh:issue-refresh-token webid client-id
(jkt (dpop-proof-jwk dpop))
#:dir refresh-token-dir))))
(values
(build-response #:headers '((content-type application/json)
(cache-control (no-cache no-store)))
#:port #f)
(stubs:scm->json-string
`((id_token . ,id-token)
(access_token . ,access-token)
(token_type . "DPoP")
(expires_in . ,validity)
(refresh_token . ,refresh-token)))
client-id
#f))))))))))
|
