Be more precise with conditional rules.

cmd/csaf_checker/rules.go

@@ -0,0 +1,114 @@
+// This file is Free Software under the MIT License
+// without warranty, see README.md and LICENSES/MIT.txt for details.
+//
+// SPDX-License-Identifier: MIT
+//
+// SPDX-FileCopyrightText: 2023 German Federal Office for Information Security (BSI) <https://www.bsi.bund.de>
+// Software-Engineering: 2023 Intevation GmbH <https://intevation.de>
+
+package main
+
+import (
+	"sort"
+
+	"github.com/csaf-poc/csaf_distribution/v2/csaf"
+)
+
+type ruleCondition int
+
+const (
+	condAll ruleCondition = iota
+	condOneOf
+)
+
+type requirementRules struct {
+	cond      ruleCondition
+	satisfies int
+	subs      []*requirementRules
+}
+
+var (
+	publisherRules = &requirementRules{
+		cond: condAll,
+		subs: ruleAtoms(1, 2, 3 /* 4 */),
+	}
+
+	providerRules = &requirementRules{
+		cond: condAll,
+		subs: []*requirementRules{
+			publisherRules,
+			{cond: condOneOf, subs: ruleAtoms(8, 9, 10)},
+			{cond: condOneOf, subs: []*requirementRules{
+				{cond: condAll, subs: ruleAtoms(11, 12, 13, 14)},
+				{cond: condAll, subs: ruleAtoms(15, 16, 17)},
+			}},
+		},
+	}
+
+	trustedProviderRules = &requirementRules{
+		cond: condAll,
+		subs: []*requirementRules{
+			providerRules,
+			{cond: condAll, subs: ruleAtoms(18, 19, 20)},
+		},
+	}
+)
+
+func ruleAtoms(nums ...int) []*requirementRules {
+	rules := make([]*requirementRules, len(nums))
+	for i, num := range nums {
+		rules[i] = &requirementRules{
+			cond:      condAll,
+			satisfies: num,
+		}
+	}
+	return rules
+}
+
+func (rules *requirementRules) reporters() []reporter {
+	if rules == nil {
+		return nil
+	}
+	var nums []int
+
+	var recurse func(*requirementRules)
+	recurse = func(rules *requirementRules) {
+		if rules.satisfies != 0 {
+			// There should not be any dupes
+			for _, n := range nums {
+				if n == rules.satisfies {
+					goto doRecurse
+				}
+			}
+			nums = append(nums, rules.satisfies)
+		}
+	doRecurse:
+		for _, sub := range rules.subs {
+			recurse(sub)
+		}
+	}
+	recurse(rules)
+
+	sort.Ints(nums)
+
+	reps := make([]reporter, len(nums))
+
+	for i, n := range nums {
+		reps[i] = reporters[n]
+	}
+	return reps
+}
+
+// roleRequirements returns the rules for the given role.
+func roleRequirements(role csaf.MetadataRole) *requirementRules {
+	switch role {
+	case csaf.MetadataRoleTrustedProvider:
+		return trustedProviderRules
+	case csaf.MetadataRoleProvider:
+		return providerRules
+	case csaf.MetadataRolePublisher:
+		return publisherRules
+	default:
+		return nil
+	}
+}