AttributionSource

Kotlin |Java

class AttributionSource : Parcelable

kotlin.Any
↳	android.content.AttributionSource

This class represents a source to which access to permission protected data should be attributed. Attribution sources can be chained to represent cases where the protected data would flow through several applications. For example, app A may ask app B for contacts and in turn app B may ask app C for contacts. In this case, the attribution chain would be A -> B -> C and the data flow would be C -> B -> A. There are two main benefits of using the attribution source mechanism: avoid doing explicit permission checks on behalf of the calling app if you are accessing private data on their behalf to send back; avoid double data access blaming which happens as you check the calling app's permissions and when you access the data behind these permissions (for runtime permissions). Also if not explicitly blaming the caller the data access would be counted towards your app vs to the previous app where yours was just a proxy.

Every Context has an attribution source and you can get it via android.content.Context#getAttributionSource() representing itself, which is a chain of one. You can attribute work to another app, or more precisely to a chain of apps, through which the data you would be accessing would flow, via Context.createContext( plus specifying an attribution source for the next app to receive the protected data you are accessing via AttributionSource.Builder.setNext(. Creating this attribution chain ensures that the datasource would check whether every app in the attribution chain has permission to access the data before releasing it. The datasource will also record appropriately that this data was accessed by the apps in the sequence if the data is behind a sensitive permission (e.g. dangerous). Again, this is useful if you are accessing the data on behalf of another app, for example a speech recognizer using the mic so it can provide recognition to a calling app.

You can create an attribution chain of you and any other app without any verification as this is something already available via the android.app.AppOpsManager APIs. This is supported to handle cases where you don't have access to the caller's attribution source and you can directly use the AttributionSource.Builder APIs. However, if the data flows through more than two apps (more than you access the data for the caller) you need to have a handle to the AttributionSource for the calling app's context in order to create an attribution context. This means you either need to have an API for the other app to send you its attribution source or use a platform API that pipes the callers attribution source.

You cannot forge an attribution chain without the participation of every app in the attribution chain (aside of the special case mentioned above). To create an attribution source that is trusted you need to create an attribution context that points to an attribution source that was explicitly created by the app that it refers to, recursively.

Since creating an attribution context leads to all permissions for apps in the attribution chain being checked, you need to expect getting a security exception when accessing permission protected APIs since some app in the chain may not have the permission.

Summary

Nested classes
	`Builder` A builder for `AttributionSource`

Inherited constants

From class Parcelable

Int

CONTENTS_FILE_DESCRIPTOR

Descriptor bit used with describeContents(): indicates that the Parcelable object's flattened representation includes a file descriptor.

Int

PARCELABLE_WRITE_RETURN_VALUE

Flag for use with writeToParcel: the object being written is a return value, that is the result of a function such as "Parcelable someFunction()", "void someFunction(out Parcelable)", or "void someFunction(inout Parcelable)". Some implementations may want to release resources at this point.

Public methods
Boolean	`checkCallingUid()` If you are handling an IPC and you don't trust the caller you need to validate whether the attribution source is one for the calling app to prevent the caller to pass you a source from another app without including themselves in the attribution chain.
Int	`describeContents()`
Unit	`enforceCallingUid()` If you are handling an IPC and you don't trust the caller you need to validate whether the attribution source is one for the calling app to prevent the caller to pass you a source from another app without including themselves in the attribution chain.
Boolean	`equals(other: Any?)` Indicates whether some other object is "equal to" this one.
String?	`getAttributionTag()` The attribution tag of the app accessing the permission protected data.
Int	`getDeviceId()` Gets the device ID for this attribution source.
AttributionSource?	`getNext()` The next app to receive the permission protected data.
String?	`getPackageName()` The package that is accessing the permission protected data.
Int	`getPid()` The PID that is accessing the permission protected data.
Int	`getUid()` The UID that is accessing the permission protected data.
Int	`hashCode()`
Boolean	`isTrusted(context: Context)` Checks whether this attribution source can be trusted.
static AttributionSource	`myAttributionSource()` Returns a generic `AttributionSource` that represents the entire calling process.
String	`toString()`
Unit	`writeToParcel(dest: Parcel, flags: Int)` Flatten this object in to a Parcel.

Properties
static Parcelable.Creator<AttributionSource!>	`CREATOR`

Public methods

checkCallingUid

Added in API level 31

fun checkCallingUid(): Boolean

If you are handling an IPC and you don't trust the caller you need to validate whether the attribution source is one for the calling app to prevent the caller to pass you a source from another app without including themselves in the attribution chain.

Return
`Boolean`	if the attribution source cannot be trusted to be from the caller.

describeContents

Added in API level 31

fun describeContents(): Int

Return
`Int`	a bitmask indicating the set of special object types marshaled by this Parcelable object instance. Value is either `0` or `android.os.Parcelable#CONTENTS_FILE_DESCRIPTOR`

enforceCallingUid

Added in API level 31

fun enforceCallingUid(): Unit

Exceptions
`java.lang.SecurityException`	if the attribution source cannot be trusted to be from the caller.

equals

Added in API level 31

fun equals(other: Any?): Boolean

Indicates whether some other object is "equal to" this one.

The equals method implements an equivalence relation on non-null object references:

It is reflexive: for any non-null reference value x, x.equals(x) should return true.
It is symmetric: for any non-null reference values x and y, x.equals(y) should return true if and only if y.equals(x) returns true.
It is transitive: for any non-null reference values x, y, and z, if x.equals(y) returns true and y.equals(z) returns true, then x.equals(z) should return true.
It is consistent: for any non-null reference values x and y, multiple invocations of x.equals(y) consistently return true or consistently return false, provided no information used in equals comparisons on the objects is modified.
For any non-null reference value x, x.equals(null) should return false.

An equivalence relation partitions the elements it operates on into equivalence classes; all the members of an equivalence class are equal to each other. Members of an equivalence class are substitutable for each other, at least for some purposes.

Parameters
`obj`	the reference object with which to compare.
`o`	This value may be `null`.

Return
`Boolean`	`true` if this object is the same as the obj argument; `false` otherwise.

getAttributionTag

Added in API level 31

fun getAttributionTag(): String?

The attribution tag of the app accessing the permission protected data.

Return
`String?`	This value may be `null`.

getDeviceId

Added in API level 35

fun getDeviceId(): Int

Gets the device ID for this attribution source. Attribution source can set the device ID using Builder.setDeviceId(int), the default device ID is Context.DEVICE_ID_DEFAULT.

This device ID is used for permissions checking during attribution source validation.

getNext

Added in API level 31

fun getNext(): AttributionSource?

The next app to receive the permission protected data.

Return
`AttributionSource?`	This value may be `null`.

getPackageName

Added in API level 31

fun getPackageName(): String?

The package that is accessing the permission protected data.

Return
`String?`	This value may be `null`.

getPid

Added in API level 34

fun getPid(): Int

The PID that is accessing the permission protected data.

getUid

Added in API level 31

fun getUid(): Int

The UID that is accessing the permission protected data.

hashCode

Added in API level 31

fun hashCode(): Int

Return
`Int`	a hash code value for this object.

isTrusted

Added in API level 31

fun isTrusted(context: Context): Boolean

Checks whether this attribution source can be trusted. That is whether the app it refers to created it and provided to the attribution chain.

Parameters
`context`	Context: Context handle. This value cannot be `null`.

Return
`Boolean`	Whether this is a trusted source.

myAttributionSource

Added in API level 33

static fun myAttributionSource(): AttributionSource

Returns a generic AttributionSource that represents the entire calling process.

Callers are strongly encouraged to use a more specific attribution source whenever possible, such as from Context.getAttributionSource(), since that enables developers to have more detailed and scoped control over attribution within sub-components of their app.

Return
`AttributionSource`	a generic `AttributionSource` representing the entire calling process This value cannot be `null`.

Exceptions
`java.lang.IllegalStateException`	when no accurate `AttributionSource` can be determined

See Also

toString

Added in API level 31

fun toString(): String

Return
`String`	a string representation of the object.

writeToParcel

Added in API level 31

fun writeToParcel(
    dest: Parcel, 
    flags: Int
): Unit

Flatten this object in to a Parcel.

Parameters
`dest`	Parcel: This value cannot be `null`.
`flags`	Int: Additional flags about how the object should be written. May be 0 or `PARCELABLE_WRITE_RETURN_VALUE`. Value is either `0` or a combination of `android.os.Parcelable#PARCELABLE_WRITE_RETURN_VALUE`, and android.os.Parcelable.PARCELABLE_ELIDE_DUPLICATES

Properties

CREATOR

Added in API level 31

static val CREATOR: Parcelable.Creator<AttributionSource!>