Refactor Android.bp build modules for readability
When we compile sepolicy files into a cil file, we first gather all
sepolicy files to create a conf file, and then convert the conf file to
a cil file with checkpolicy. The problem is that checkpolicy is
sensitive to the input order; the conf file should contain statements in
a specific order: classes, initial_sid, access vectors, macros, mls,
etc.
This restriction has made Android.bp migration difficult, and we had to
create a magical module called "se_build_files" to correctly include
source files in the designated order. It works, but significant
readability problem has happened. For example, when we write
":se_build_files{.system_ext_public}", how can we easily figure out that
the tag actually includes plat public + system_ext public + reqd mask,
without taking a look at the build system code?
This change refactors the se_build_files module and se_policy_conf
module, so we can easily see the desginated files for each module, just
like we did in the Android.mk. se_policy_conf module now stably sorts
source files in an order which will make checkpolicy happy.
se_build_files module is also refactored, so one tag can represent
exactly one set of policy files, rather than doing magical works behind
the scene. For example, system_ext public policy module is changed from:
se_policy_conf {
name: "system_ext_pub_policy.conf",
// se_build_files automatically adds plat public and reqd mask
srcs: [":se_build_files{.system_ext_public}"],
}
to:
se_policy_conf {
name: "system_ext_pub_policy.conf",
// se_policy_conf automatically sorts the input files
srcs: [
":se_build_files{.plat_public}",
":se_build_files{.system_ext_public}",
":se_build_files{.reqd_mask}",
],
}
Bug: 209933272
Test: build and diff before/after
Change-Id: I97a76ed910645c1607d913fd646c27e87af0afd3
diff --git a/Android.bp b/Android.bp
index 9a13c9c..d22010c 100644
--- a/Android.bp
+++ b/Android.bp
@@ -661,6 +661,14 @@
],
}
+reqd_mask_policy = [":se_build_files{.reqd_mask}"]
+plat_public_policy = [":se_build_files{.plat_public}"]
+plat_private_policy = [":se_build_files{.plat_private}"]
+system_ext_public_policy = [":se_build_files{.system_ext_public}"]
+system_ext_private_policy = [":se_build_files{.system_ext_private}"]
+product_public_policy = [":se_build_files{.product_public}"]
+product_private_policy = [":se_build_files{.product_private}"]
+
// reqd_policy_mask - a policy.conf file which contains only the bare minimum
// policy necessary to use checkpolicy.
//
@@ -671,7 +679,7 @@
// policy and subsequent removal of CIL policy that should not be exported.
se_policy_conf {
name: "reqd_policy_mask.conf",
- srcs: [":se_build_files{.reqd_mask}"],
+ srcs: reqd_mask_policy,
installable: false,
}
@@ -706,7 +714,10 @@
//
se_policy_conf {
name: "pub_policy.conf",
- srcs: [":se_build_files{.product_public}"], // product_ includes system and system_ext
+ srcs: plat_public_policy +
+ system_ext_public_policy +
+ product_public_policy +
+ reqd_mask_policy,
installable: false,
}
@@ -720,7 +731,9 @@
se_policy_conf {
name: "system_ext_pub_policy.conf",
- srcs: [":se_build_files{.system_ext_public}"], // system_ext_public includes system
+ srcs: plat_public_policy +
+ system_ext_public_policy +
+ reqd_mask_policy,
installable: false,
}
@@ -734,7 +747,8 @@
se_policy_conf {
name: "plat_pub_policy.conf",
- srcs: [":se_build_files{.plat_public}"],
+ srcs: plat_public_policy +
+ reqd_mask_policy,
installable: false,
}
@@ -753,7 +767,8 @@
// currently being attributized.
se_policy_conf {
name: "plat_sepolicy.conf",
- srcs: [":se_build_files{.plat}"],
+ srcs: plat_public_policy +
+ plat_private_policy,
installable: false,
}
@@ -766,7 +781,8 @@
// userdebug_plat_policy.conf - the userdebug version plat_sepolicy.cil
se_policy_conf {
name: "userdebug_plat_sepolicy.conf",
- srcs: [":se_build_files{.plat}"],
+ srcs: plat_public_policy +
+ plat_private_policy,
build_variant: "userdebug",
installable: false,
}
@@ -815,7 +831,10 @@
// policy which will ship with the device. System_ext policy is not attributized
se_policy_conf {
name: "system_ext_sepolicy.conf",
- srcs: [":se_build_files{.system_ext}"],
+ srcs: plat_public_policy +
+ plat_private_policy +
+ system_ext_public_policy +
+ system_ext_private_policy,
installable: false,
}
@@ -831,7 +850,12 @@
// which will ship with the device. Product policy is not attributized
se_policy_conf {
name: "product_sepolicy.conf",
- srcs: [":se_build_files{.product}"],
+ srcs: plat_public_policy +
+ plat_private_policy +
+ system_ext_public_policy +
+ system_ext_private_policy +
+ product_public_policy +
+ product_private_policy,
installable: false,
}
@@ -1017,7 +1041,8 @@
//////////////////////////////////
se_policy_conf {
name: "general_sepolicy.conf",
- srcs: [":se_build_files{.plat}"],
+ srcs: plat_public_policy +
+ plat_private_policy,
build_variant: "user",
cts: true,
exclude_build_test: true,
@@ -1032,7 +1057,8 @@
//////////////////////////////////
se_policy_conf {
name: "base_plat_sepolicy.conf",
- srcs: [":se_build_files{.plat}"],
+ srcs: plat_public_policy +
+ plat_private_policy,
build_variant: "user",
installable: false,
}
@@ -1053,7 +1079,10 @@
se_policy_conf {
name: "base_system_ext_sepolicy.conf",
- srcs: [":se_build_files{.system_ext}"],
+ srcs: plat_public_policy +
+ plat_private_policy +
+ system_ext_public_policy +
+ system_ext_private_policy,
build_variant: "user",
installable: false,
}
@@ -1076,7 +1105,12 @@
se_policy_conf {
name: "base_product_sepolicy.conf",
- srcs: [":se_build_files{.product}"],
+ srcs: plat_public_policy +
+ plat_private_policy +
+ system_ext_public_policy +
+ system_ext_private_policy +
+ product_public_policy +
+ product_private_policy,
build_variant: "user",
installable: false,
}
@@ -1099,7 +1133,8 @@
se_policy_conf {
name: "base_plat_pub_policy.conf",
- srcs: [":se_build_files{.plat_public}"],
+ srcs: plat_public_policy +
+ reqd_mask_policy,
build_variant: "user",
installable: false,
}
@@ -1114,7 +1149,9 @@
se_policy_conf {
name: "base_system_ext_pub_policy.conf",
- srcs: [":se_build_files{.system_ext_public}"], // system_ext_public includes system
+ srcs: plat_public_policy +
+ system_ext_public_policy +
+ reqd_mask_policy,
build_variant: "user",
installable: false,
}
@@ -1129,7 +1166,10 @@
se_policy_conf {
name: "base_product_pub_policy.conf",
- srcs: [":se_build_files{.product_public}"], // product_ includes system and system_ext
+ srcs: plat_public_policy +
+ system_ext_public_policy +
+ product_public_policy +
+ reqd_mask_policy,
build_variant: "user",
installable: false,
}
diff --git a/build/soong/build_files.go b/build/soong/build_files.go
index 5de6122..8f77e4f 100644
--- a/build/soong/build_files.go
+++ b/build/soong/build_files.go
@@ -17,7 +17,6 @@
import (
"fmt"
"path/filepath"
- "sort"
"strings"
"android/soong/android"
@@ -29,8 +28,8 @@
// se_build_files gathers policy files from sepolicy dirs, and acts like a filegroup. A tag with
// partition(plat, system_ext, product) and scope(public, private) is used to select directories.
-// Supported tags are: "plat", "plat_public", "system_ext", "system_ext_public", "product",
-// "product_public", and "reqd_mask".
+// Supported tags are: "plat_public", "plat_private", "system_ext_public", "system_ext_private",
+// "product_public", "product_private", and "reqd_mask".
func buildFilesFactory() android.Module {
module := &buildFiles{}
module.AddProperties(&module.properties)
@@ -86,114 +85,18 @@
var _ android.OutputFileProducer = (*buildFiles)(nil)
-type partition int
-
-const (
- system partition = iota
- system_ext
- product
-)
-
-type scope int
-
-const (
- public scope = iota
- private
-)
-
type sepolicyDir struct {
- partition partition
- scope scope
- paths []string
-}
-
-func (p partition) String() string {
- switch p {
- case system:
- return "plat"
- case system_ext:
- return "system_ext"
- case product:
- return "product"
- default:
- panic(fmt.Sprintf("Unknown partition %#v", p))
- }
+ tag string
+ paths []string
}
func (b *buildFiles) GenerateAndroidBuildActions(ctx android.ModuleContext) {
- // Sepolicy directories should be included in the following order.
- // - system_public
- // - system_private
- // - system_ext_public
- // - system_ext_private
- // - product_public
- // - product_private
- dirs := []sepolicyDir{
- sepolicyDir{partition: system, scope: public, paths: []string{filepath.Join(ctx.ModuleDir(), "public")}},
- sepolicyDir{partition: system, scope: private, paths: []string{filepath.Join(ctx.ModuleDir(), "private")}},
- sepolicyDir{partition: system_ext, scope: public, paths: ctx.DeviceConfig().SystemExtPublicSepolicyDirs()},
- sepolicyDir{partition: system_ext, scope: private, paths: ctx.DeviceConfig().SystemExtPrivateSepolicyDirs()},
- sepolicyDir{partition: product, scope: public, paths: ctx.Config().ProductPublicSepolicyDirs()},
- sepolicyDir{partition: product, scope: private, paths: ctx.Config().ProductPrivateSepolicyDirs()},
- }
-
- if !sort.SliceIsSorted(dirs, func(i, j int) bool {
- if dirs[i].partition != dirs[j].partition {
- return dirs[i].partition < dirs[j].partition
- }
-
- return dirs[i].scope < dirs[j].scope
- }) {
- panic("dirs is not sorted")
- }
-
- // Exported cil policy files are built with the following policies.
- //
- // - plat_pub_policy.cil: exported 'system'
- // - system_ext_pub_policy.cil: exported 'system' and 'system_ext'
- // - pub_policy.cil: exported 'system', 'system_ext', and 'product'
- //
- // cil policy files are built with the following policies.
- //
- // - plat_policy.cil: 'system', including private
- // - system_ext_policy.cil: 'system_ext', including private
- // - product_sepolicy.cil: 'product', including private
- //
- // gatherDirsFor collects all needed directories for given partition and scope. For example,
- //
- // - gatherDirsFor(system_ext, private) will return system + system_ext (including private)
- // - gatherDirsFor(product, public) will return system + system_ext + product (public only)
- //
- // "dirs" should be sorted before calling this.
- gatherDirsFor := func(p partition, s scope) []string {
- var ret []string
-
- for _, d := range dirs {
- if d.partition <= p && d.scope <= s {
- ret = append(ret, d.paths...)
- }
- }
-
- return ret
- }
-
- reqdMaskDir := filepath.Join(ctx.ModuleDir(), "reqd_mask")
-
b.srcs = make(map[string]android.Paths)
- b.srcs[".reqd_mask"] = b.findSrcsInDirs(ctx, reqdMaskDir)
-
- for _, p := range []partition{system, system_ext, product} {
- b.srcs["."+p.String()] = b.findSrcsInDirs(ctx, gatherDirsFor(p, private)...)
-
- // reqd_mask is needed for public policies
- b.srcs["."+p.String()+"_public"] = b.findSrcsInDirs(ctx, append(gatherDirsFor(p, public), reqdMaskDir)...)
- }
-
- // A special tag, "plat_vendor", includes minimized vendor policies required to boot.
- // - system/sepolicy/public
- // - system/sepolicy/reqd_mask
- // - system/sepolicy/vendor
- // This is for minimized vendor partition, e.g. microdroid's vendor
- platVendorDir := filepath.Join(ctx.ModuleDir(), "vendor")
- b.srcs[".plat_vendor"] = b.findSrcsInDirs(ctx, append(gatherDirsFor(system, public), reqdMaskDir, platVendorDir)...)
+ b.srcs[".reqd_mask"] = b.findSrcsInDirs(ctx, filepath.Join(ctx.ModuleDir(), "reqd_mask"))
+ b.srcs[".plat_public"] = b.findSrcsInDirs(ctx, filepath.Join(ctx.ModuleDir(), "public"))
+ b.srcs[".plat_private"] = b.findSrcsInDirs(ctx, filepath.Join(ctx.ModuleDir(), "private"))
+ b.srcs[".system_ext_public"] = b.findSrcsInDirs(ctx, ctx.DeviceConfig().SystemExtPublicSepolicyDirs()...)
+ b.srcs[".system_ext_private"] = b.findSrcsInDirs(ctx, ctx.DeviceConfig().SystemExtPrivateSepolicyDirs()...)
+ b.srcs[".product_public"] = b.findSrcsInDirs(ctx, ctx.Config().ProductPublicSepolicyDirs()...)
+ b.srcs[".product_private"] = b.findSrcsInDirs(ctx, ctx.Config().ProductPrivateSepolicyDirs()...)
}
diff --git a/build/soong/policy.go b/build/soong/policy.go
index 82fabe3..8d0e1a4 100644
--- a/build/soong/policy.go
+++ b/build/soong/policy.go
@@ -17,7 +17,9 @@
import (
"fmt"
"os"
+ "sort"
"strconv"
+ "strings"
"github.com/google/blueprint/proptools"
@@ -31,6 +33,31 @@
PolicyVers = 30
)
+// This order should be kept. checkpolicy syntax requires it.
+var policyConfOrder = []string{
+ "security_classes",
+ "initial_sids",
+ "access_vectors",
+ "global_macros",
+ "neverallow_macros",
+ "mls_macros",
+ "mls_decl",
+ "mls",
+ "policy_capabilities",
+ "te_macros",
+ "attributes",
+ "ioctl_defines",
+ "ioctl_macros",
+ "*.te",
+ "roles_decl",
+ "roles",
+ "users",
+ "initial_sid_contexts",
+ "fs_use",
+ "genfs_contexts",
+ "port_contexts",
+}
+
func init() {
android.RegisterModuleType("se_policy_conf", policyConfFactory)
android.RegisterModuleType("se_policy_cil", policyCilFactory)
@@ -143,9 +170,25 @@
return strconv.FormatBool(ctx.DeviceConfig().BuildDebugfsRestrictionsEnabled())
}
+func findPolicyConfOrder(name string) int {
+ for idx, pattern := range policyConfOrder {
+ if pattern == name || (pattern == "*.te" && strings.HasSuffix(name, ".te")) {
+ return idx
+ }
+ }
+ // name is not matched
+ return len(policyConfOrder)
+}
+
func (c *policyConf) transformPolicyToConf(ctx android.ModuleContext) android.OutputPath {
conf := android.PathForModuleOut(ctx, "conf").OutputPath
rule := android.NewRuleBuilder(pctx, ctx)
+
+ srcs := android.PathsForModuleSrc(ctx, c.properties.Srcs)
+ sort.SliceStable(srcs, func(x, y int) bool {
+ return findPolicyConfOrder(srcs[x].Base()) < findPolicyConfOrder(srcs[y].Base())
+ })
+
rule.Command().Tool(ctx.Config().PrebuiltBuildTool(ctx, "m4")).
Flag("--fatal-warnings").
FlagForEachArg("-D ", ctx.DeviceConfig().SepolicyM4Defs()).
@@ -164,7 +207,7 @@
FlagWithArg("-D target_requires_insecure_execmem_for_swiftshader=", strconv.FormatBool(ctx.DeviceConfig().RequiresInsecureExecmemForSwiftshader())).
FlagWithArg("-D target_enforce_debugfs_restriction=", c.enforceDebugfsRestrictions(ctx)).
Flag("-s").
- Inputs(android.PathsForModuleSrc(ctx, c.properties.Srcs)).
+ Inputs(srcs).
Text("> ").Output(conf)
rule.Build("conf", "Transform policy to conf: "+ctx.ModuleName())