frostfs-s3-gw/api/auth/signer/v4/header_rules.go

88 lines
2.0 KiB
Go

package v4
import (
"strings"
)
// validator houses a set of rule needed for validation of a
// string value.
type rules []rule
// rule interface allows for more flexible rules and just simply
// checks whether or not a value adheres to that rule.
type rule interface {
IsValid(value string) bool
}
// IsValid will iterate through all rules and see if any rules
// apply to the value and supports nested rules.
func (r rules) IsValid(value string) bool {
for _, rule := range r {
if rule.IsValid(value) {
return true
}
}
return false
}
// mapRule generic rule for maps.
type mapRule map[string]struct{}
// IsValid for the map rule satisfies whether it exists in the map.
func (m mapRule) IsValid(value string) bool {
_, ok := m[value]
return ok
}
// whitelist is a generic rule for whitelisting.
type whitelist struct {
rule
}
// IsValid for whitelist checks if the value is within the whitelist.
func (w whitelist) IsValid(value string) bool {
return w.rule.IsValid(value)
}
// blacklist is a generic rule for blacklisting.
type blacklist struct {
rule
}
// IsValid for whitelist checks if the value is within the whitelist.
func (b blacklist) IsValid(value string) bool {
return !b.rule.IsValid(value)
}
type patterns []string
// IsValid for patterns checks each pattern and returns if a match has
// been found.
func (p patterns) IsValid(value string) bool {
for _, pattern := range p {
if HasPrefixFold(value, pattern) {
return true
}
}
return false
}
// HasPrefixFold tests whether the string s begins with prefix, interpreted as UTF-8 strings,
// under Unicode case-folding.
func HasPrefixFold(s, prefix string) bool {
return len(s) >= len(prefix) && strings.EqualFold(s[0:len(prefix)], prefix)
}
// inclusiveRules rules allow for rules to depend on one another.
type inclusiveRules []rule
// IsValid will return true if all rules are true.
func (r inclusiveRules) IsValid(value string) bool {
for _, rule := range r {
if !rule.IsValid(value) {
return false
}
}
return true
}