Apple Inc.

Julien Lerouge

Augustin J Farrugia

Gideon M Myles

Gianpaolo Fasoli

Jon McLachlan

Tanya Michelle Lattner

Jonathan McLachlan

Daniel F Reynaud

Pierre Betouin

Mathieu Ciet

Ganna Zaks

Taylor Gerard Carrigan

David Chance Graham

Thomas M Alsina

Bob Bradley

Nicholas Thomas Sullivan

Johannes P Schmidt

Nicholas James Paulson

James C Grandy

Ginger Marie Myles

Pierre De Lastic

Haishan Ye

Benoit Chevallier-Mames

Cédric Tessier

Thomas Icart

Srinivas Vedula

Eric Daniel Friedman

Christopher Arthur Lattner

Ritwik K Kumar

Libor Sykora

Lucas Olen Winstrom

Amol V Pattekar

Erika Misaki

Paul J Sholtz

Delfin Jorge Rojas

Jean-Baptiste Aviat

Eric D Laspe

Lawrence Aung

Shiva Krovi

Jeremy M Stober

Techniques are disclosed relating to authentication using public key encryption. In one embodiment, a computing device includes a secure circuit, a processor, and memory. The secure circuit is configured to generate a public key pair usable to authenticate a user of the computing device. The memory has program instructions stored therein that are executable by the processor to cause the computing device to perform operations including authenticating the user with a server system by sending authentication information supplied by the user. The operations further include, in response to the server system verifying the authentication information, receiving a first token usable to register the public key pair with the server system and sending, to the server system, a request to register the public key pair for authenticating the user. In such an embodiment, the request includes the first token and identifies a public key of the public key pair.

Authentication using a secure circuit

In some implementations, a computing device can transfer a playback queue between the computing device and a playback device. For example, the computing device can detect when the computing device is within a threshold distance of a playback device. The computing device can establish a connection to the playback device and receive state information describing the media playback state of the playback device. The computing device can determine the media playback state of the computing device. The computing device can present graphical user interfaces for initiating a transfer of a playback queue between the computing device and the playback device based on the playback state of the devices. The computing device can initiate a transfer of the playback queue in response to user input to one of the graphical user interfaces or automatically based on the context of the computing device.

Transferring playback queues between devices

In some implementations, a computing system can be configured so that a first user device can delegate a first user's media account credentials to second user device corresponding to a second user. For example, a playback device may be configured with the second user's media account credentials for accessing media items through a network media service. A first user may wish to play media items associated with the first user's media account credentials on the playback device. To do so, the first user device can request a device identifier for the playback device, request and obtain a delegate token for the device identifier from the media service, and provide the delegate token along with media item information to the playback device. The playback device can then use the delegate token to request the media item associated with the first user's media access account.

Credential delegation

Systems and methods are described for rate-limiting a message-sending client interacting with a message service based on dynamically calculated risk assessments of the probability that the client is, or is not, a sender of a spam messages. The message service sends a proof of work problem to a sending client device with a difficulty level that is related to a risk assessment that the client is a sender of spam messages. The message system limits the rate at which a known or suspected spammer can send messages by giving the known or suspected spammer client harder proof of work problems to solve, while minimizing the burden on normal users of the message system by given them easier proof of work problems to solve that can typically be solved by the client within the time that it takes to type a message.

Method for rate-limiting interactions based on dynamically calculated values by supplying problems of varying difficulty to be solved

An obfuscated program can be configured to resist attacks in which an attacker directly calls a non-entry function by verifying that an execution path to the function is an authorized execution path. To detect an unauthorized execution order, a secret value is embedded in each function along an authorized execution path. At runtime, the secrets are combined to generate a runtime representation of the execution path, and the runtime representation is verified against an expected value. To perform the verification, a verification polynomial is evaluated using the runtime representation as input. A verification value result of zero means the execution path is an authorized execution path.

Preventing unauthorized calls to a protected function

Methods, media and systems that use an encoded opaque pointer in an API between a client process and a library process. An encoded opaque pointer, in one embodiment, can be received by the library process from the client process, and the library process can decode the opaque pointer to obtain an address in memory containing a data structure pointed to by the opaque pointer. The library process can operate on the data structure to create a revised or processed data structure, stored in the same or different address in heap memory or stack memory, and the library process can encode and return a new opaque pointer, for the processed data structure, to the client process.

Data protection for opaque data structures

A method and an apparatus that provide rewriting code to dynamically mask program data statically embedded in a first code are described. The program data can be used in multiple instructions in the first code. A code location (e.g. an optimal code location) in the first code can be determined for injecting the rewriting code. The code location may be included in two or more execution paths of first code. Each execution path can have at least one of the instructions using the program data. A second code may be generated based on the first code inserted with the rewriting code at the optimal code location. The second code can include instructions using the program data dynamically masked by the rewriting code. When executed by a processor, the first code and the second code can generate identical results.

Method and apparatus for dynamic obfuscation of static data

Techniques, methods, systems, and computer-readable media for allocating and managing dynamically obfuscated heap memory allocations are described. In one embodiment a memory manager in a data processing system contains an addressor, to determine a first address of a program object in a first memory address space, and one or more encoders, to abstract memory access to the program object using the first address such that layout of the object data in the first address space differs from the layout of the object in a second address space. In one embodiment, a runtime system modifies object code of an executable file to include encoder routines to abstract memory accesses to data in an obfuscated heap. In one embodiment, a compiler system using an intermediate representation of a high level program generates an intermediate representation of a high level program capable of performing memory writes and memory reads using obfuscation encoder routines.

Dynamic obfuscation of heap memory allocations

Disclosed herein are systems, methods, and non-transitory computer-readable storage media for obfuscating data using instructions as a source of pseudorandom values. Obfuscation is performed by receiving instructions and data and compiling the instructions and the data into an executable file having a text section and a data section. The text section can include instructions and the data section can include data segments. The system obfuscates the data section iteratively by generating a hash of an address for a respective data segment, and based on the hash, identifying a corresponding address in the text section that includes at least one instruction. The system retrieves a mask key from the corresponding address and applies the mask key to the respective data segment, yielding a masked data segment. In one embodiment, integrity verification of obfuscated data is performed without exposing the data in an unprotected state by utilizing multiple mask keys.

System and method for obfuscating data using instructions as a source of pseudorandom values

In one embodiment, a system wide static global stack pool in a contiguous range of random access memory is generated, a block of memory in the system global pool is assigned to a thread of a running process, and the thread stores local variable information in static global stack pool, such that the local variable is hidden from a stack frame back-trace. In one embodiment, a dynamically allocated data structure in system heap memory is generated, the data structure is locked to ensure atomic access, a block of memory in the data structure is assigned to a thread of a process, the data structure is unlocked, and the thread stores local variable information in static global stack pool, such that the local variable is hidden from a stack frame back-trace.

Obfuscating function resources while reducing stack consumption

A branch auditing system can be automatically injected into a computer program, in one embodiment, in response to a programming call provided in source code by a programmer who has selected a particular branch, in a set of possible branches, for auditing. The branch auditing system can record, in an obfuscated data structure, a path taken at the particular branch and the parameters associated with the branch and later an auditor can determine whether the path taken was valid, and if the path taken was invalid, operations can be performed to protect the program, system and/or user.

Branch auditing in a computer program

Disclosed herein are systems, methods, and computer-readable storage media for obfuscating using inlined functions. A system configured to practice the method receives a program listing including annotated functions for obfuscation, identifies an annotated function called more than once in the program listing, and creates an inline control flow structure in the program listing for the identified annotated function, the control flow structure being computationally equivalent to inlining the identified annotated function into the program listing for each occurrence of the identified annotated function. The program listing can include tiers of annotated functions. The system can identify annotated functions called more than once based on an optionally generated callgraph. The system can create inline control flow structures in the program listing in order of annotation importance. The system can identify how many times each annotated function is called in the program listing.

System and method for annotation-driven function inlining

In the field of computer software, obfuscation techniques for enhancing software security are applied to compiled (object) software code. The obfuscation results here in different versions (instances) of the obfuscated code being provided to different installations (recipient computing devices). The complementary code execution uses a boot loader or boot installer-type program at each installation which contains the requisite logic. Typically, the obfuscation results in a different instance of the obfuscated code for each intended installation (recipient) but each instance being semantically equivalent to the others. This is accomplished in one version by generating a random value or other parameter during the obfuscation process, and using the value to select a particular version of the obfuscating process, and then communicating the value along with boot loader or installer program software.

Method and apparatus for computer code obfuscation and deobfuscation using boot installation

Methods, media and systems that obfuscate control flow in software programs. The obfuscation can impede or prevent static flow analysis of a software program's control flow. In one embodiment, a method, performed by a data processing system, identifies each branch point in a set of branch points in a first version of software and replaces, in each branch point in the set, a representation of a target of the branch point with a computed value that depends upon at least one prior computed value in a stream of instructions in the first version of software. Other embodiments are also described.

Growing community of inventors

Santa Clara, CA, United States of America

Julien Lerouge