-
Notifications
You must be signed in to change notification settings - Fork 282
/
criteria.go
214 lines (189 loc) · 5.67 KB
/
criteria.go
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
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
// Package criteria contains all the pre-defined criteria as well as a registry to add new criteria.
package criteria
import (
"sync"
"github.com/open-policy-agent/opa/ast"
"github.com/pomerium/pomerium/pkg/policy/generator"
)
// re-exported types
type (
// A Generator generates a rego script from a policy.
Generator = generator.Generator
// A Criterion generates rego rules based on data.
Criterion = generator.Criterion
// A CriterionConstructor is a function which returns a Criterion for a Generator.
CriterionConstructor = generator.CriterionConstructor
// The CriterionDataType indicates the expected type of data for the criterion.
CriterionDataType = generator.CriterionDataType
)
var allCriteria struct {
sync.Mutex
a []CriterionConstructor
}
// All returns all the known criterion constructors.
func All() []CriterionConstructor {
allCriteria.Lock()
a := allCriteria.a
allCriteria.Unlock()
return a
}
// Register registers a criterion.
func Register(criterionConstructor CriterionConstructor) {
allCriteria.Lock()
a := make([]CriterionConstructor, 0, len(allCriteria.a)+1)
a = append(a, allCriteria.a...)
a = append(a, criterionConstructor)
allCriteria.a = a
allCriteria.Unlock()
}
const (
// CriterionDataTypeStringListMatcher indicates the expected data type is a string list matcher.
CriterionDataTypeStringListMatcher CriterionDataType = "string_list_matcher"
// CriterionDataTypeStringMatcher indicates the expected data type is a string matcher.
CriterionDataTypeStringMatcher CriterionDataType = "string_matcher"
)
// NewCriterionRule generates a new rule for a criterion.
func NewCriterionRule(
g *generator.Generator,
name string,
passReason, failReason Reason,
body ast.Body,
) *ast.Rule {
r1 := g.NewRule(name)
r1.Head.Value = NewCriterionTerm(true, passReason)
r1.Body = body
r2 := &ast.Rule{
Head: &ast.Head{
Value: NewCriterionTerm(false, failReason),
},
Body: ast.Body{
ast.NewExpr(ast.BooleanTerm(true)),
},
}
r1.Else = r2
return r1
}
// NewCriterionDeviceRule generates a new rule for a criterion which
// requires a device and session. If there is no device "device-unauthenticated"
// is returned. If there is no session "user-unauthenticated" is returned.
func NewCriterionDeviceRule(
g *generator.Generator,
name string,
passReason, failReason Reason,
body ast.Body,
deviceType string,
) *ast.Rule {
r1 := g.NewRule(name)
additionalData := map[string]interface{}{
"device_type": deviceType,
}
sharedBody := ast.Body{
ast.Assign.Expr(ast.VarTerm("device_type_id"), ast.StringTerm(deviceType)),
ast.MustParseExpr(`session := get_session(input.session.id)`),
ast.MustParseExpr(`device_credential := get_device_credential(session, device_type_id)`),
ast.MustParseExpr(`device_enrollment := get_device_enrollment(device_credential)`),
}
// case 1: rule passes, session exists, device exists
r1.Head.Value = NewCriterionTermWithAdditionalData(true, passReason, additionalData)
r1.Body = append(sharedBody, body...)
// case 2: rule fails, session exists, device exists
r2 := &ast.Rule{
Head: &ast.Head{
Value: NewCriterionTermWithAdditionalData(false, failReason, additionalData),
},
Body: append(sharedBody, ast.Body{
ast.MustParseExpr(`session.id != ""`),
ast.MustParseExpr(`device_credential.id != ""`),
ast.MustParseExpr(`device_enrollment.id != ""`),
}...),
}
r1.Else = r2
// case 3: device not authenticated, session exists, device does not exist
r3 := &ast.Rule{
Head: &ast.Head{
Value: NewCriterionTermWithAdditionalData(false, ReasonDeviceUnauthenticated, additionalData),
},
Body: append(sharedBody, ast.Body{
ast.MustParseExpr(`session.id != ""`),
}...),
}
r2.Else = r3
// case 4: user not authenticated, session does not exist
r4 := &ast.Rule{
Head: &ast.Head{
Value: NewCriterionTermWithAdditionalData(false, ReasonUserUnauthenticated, additionalData),
},
Body: ast.Body{
ast.NewExpr(ast.BooleanTerm(true)),
},
}
r3.Else = r4
return r1
}
// NewCriterionSessionRule generates a new rule for a criterion which
// requires a session. If there is no session "user-unauthenticated"
// is returned.
func NewCriterionSessionRule(
g *generator.Generator,
name string,
passReason, failReason Reason,
body ast.Body,
) *ast.Rule {
r1 := g.NewRule(name)
r1.Head.Value = NewCriterionTerm(true, passReason)
r1.Body = body
r2 := &ast.Rule{
Head: &ast.Head{
Value: NewCriterionTerm(false, failReason),
},
Body: ast.Body{
ast.MustParseExpr(`session := get_session(input.session.id)`),
ast.MustParseExpr(`session.id != ""`),
},
}
r1.Else = r2
r3 := &ast.Rule{
Head: &ast.Head{
Value: NewCriterionTerm(false, ReasonUserUnauthenticated),
},
Body: ast.Body{
ast.NewExpr(ast.BooleanTerm(true)),
},
}
r2.Else = r3
return r1
}
// NewCriterionTerm creates a new rego term for a criterion:
//
// [true, {"reason"}]
//
func NewCriterionTerm(value bool, reasons ...Reason) *ast.Term {
var terms []*ast.Term
for _, r := range reasons {
terms = append(terms, ast.StringTerm(string(r)))
}
return ast.ArrayTerm(
ast.BooleanTerm(value),
ast.SetTerm(terms...),
)
}
// NewCriterionTermWithAdditionalData creates a new rego term for a criterion with additional data:
//
// [true, {"reason"}, {"key": "value"}]
//
func NewCriterionTermWithAdditionalData(value bool, reason Reason, additionalData map[string]interface{}) *ast.Term {
var kvs [][2]*ast.Term
for k, v := range additionalData {
kvs = append(kvs, [2]*ast.Term{
ast.StringTerm(k),
ast.NewTerm(ast.MustInterfaceToValue(v)),
})
}
var terms []*ast.Term
terms = append(terms, ast.StringTerm(string(reason)))
return ast.ArrayTerm(
ast.BooleanTerm(value),
ast.SetTerm(terms...),
ast.ObjectTerm(kvs...),
)
}