ingress-nginx-helm/internal/ingress/annotations/ipwhitelist/main.go
Renan Gonçalves 869e18b264
Avoid race conditions by copying the list before sorting (#8573)
When creating several ingresses at the same time a race condition can
happen by modifying a variable deep in another object. When this race
condition is triggered the generated nginx configuration is broken:

```
nginx: [emerg] invalid parameter "8.8.8.8/32,8" in /tmp/nginx-cfg4027854160:671
nginx: configuration file /tmp/nginx-cfg4027854160 test failed
```

Once it happens, the controller won't ever be able to generate the
configuration again. Thus the only option is to restart the process.

There is not really a good way to reproduce this issue. It happens quite
sporadically every 2 or 3 days. However, after this fix has been
applied, we haven't seen it happen after about 4 weeks.

Co-authored-by: Ruud van der Weijde <ruudvanderweijde@gmail.com>
2022-05-23 05:50:03 -07:00

95 lines
2.7 KiB
Go

/*
Copyright 2016 The Kubernetes Authors.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
package ipwhitelist
import (
"fmt"
"sort"
"strings"
networking "k8s.io/api/networking/v1"
"k8s.io/ingress-nginx/internal/net"
"k8s.io/ingress-nginx/internal/ingress/annotations/parser"
ing_errors "k8s.io/ingress-nginx/internal/ingress/errors"
"k8s.io/ingress-nginx/internal/ingress/resolver"
"k8s.io/ingress-nginx/internal/sets"
)
// SourceRange returns the CIDR
type SourceRange struct {
CIDR []string `json:"cidr,omitempty"`
}
// Equal tests for equality between two SourceRange types
func (sr1 *SourceRange) Equal(sr2 *SourceRange) bool {
if sr1 == sr2 {
return true
}
if sr1 == nil || sr2 == nil {
return false
}
return sets.StringElementsMatch(sr1.CIDR, sr2.CIDR)
}
type ipwhitelist struct {
r resolver.Resolver
}
// NewParser creates a new whitelist annotation parser
func NewParser(r resolver.Resolver) parser.IngressAnnotation {
return ipwhitelist{r}
}
// ParseAnnotations parses the annotations contained in the ingress
// rule used to limit access to certain client addresses or networks.
// Multiple ranges can specified using commas as separator
// e.g. `18.0.0.0/8,56.0.0.0/8`
func (a ipwhitelist) Parse(ing *networking.Ingress) (interface{}, error) {
defBackend := a.r.GetDefaultBackend()
defaultWhitelistSourceRange := make([]string, len(defBackend.WhitelistSourceRange))
copy(defaultWhitelistSourceRange, defBackend.WhitelistSourceRange)
sort.Strings(defaultWhitelistSourceRange)
val, err := parser.GetStringAnnotation("whitelist-source-range", ing)
// A missing annotation is not a problem, just use the default
if err == ing_errors.ErrMissingAnnotations {
return &SourceRange{CIDR: defaultWhitelistSourceRange}, nil
}
values := strings.Split(val, ",")
ipnets, ips, err := net.ParseIPNets(values...)
if err != nil && len(ips) == 0 {
return &SourceRange{CIDR: defaultWhitelistSourceRange}, ing_errors.LocationDenied{
Reason: fmt.Errorf("the annotation does not contain a valid IP address or network: %w", err),
}
}
cidrs := []string{}
for k := range ipnets {
cidrs = append(cidrs, k)
}
for k := range ips {
cidrs = append(cidrs, k)
}
sort.Strings(cidrs)
return &SourceRange{cidrs}, nil
}