Figure B.1: FIPS mode state diagram

States used by the FIPS FSM:

Power-Off

Libgcrypt is not runtime linked to another application. This usually means that the library is not loaded into main memory. This state is documentation only.

Power-On

Libgcrypt is loaded into memory and API calls may be made. Compiler introducted constructor functions may be run. Note that Libgcrypt does not implement any arbitrary constructor functions to be called by the operating system

Init

The Libgcrypt initialization functions are performed and the library has not yet run any self-test.

Self-Test

Libgcrypt is performing self-tests.

Operational

Libgcrypt is in the operational state and all interfaces may be used.

Error

Libgrypt is in the error state. When calling any FIPS relevant interfaces they either return an error (GPG_ERR_NOT_OPERATIONAL) or put Libgcrypt into the Fatal-Error state and won't return.

Fatal-Error

Libgcrypt is in a non-recoverable error state and will automatically transit into the Shutdown state.

Shutdown

Libgcrypt is about to be terminated and removed from the memory. The application may at this point still runing cleanup handlers.

Table B.1: FIPS mode states

The valid state transitions (see Figure B.1) are:

1

Power-Off to Power-On is implicitly done by the OS loading Libgcrypt as a shared library and having it linked to an application.

2

Power-On to Init is triggered by the application calling the Libgcrypt intialization function gcry_check_version.

3

Init to Self-Test is either triggred by a dedicated API call or implicit by invoking a libgrypt service conrolled by the FSM.

4

Self-Test to Operational is triggered after all self-tests passed successfully.

5

Operational to Shutdown is an artifical state without any direct action in Libgcrypt. When reaching the Shutdown state the library is deinitialized and can't return to any other state again.

6

Shutdown to Power-off is the process of removing Libgcrypt from the computer's memory. For obvious reasons the Power-Off state can't be represented within Libgcrypt and thus this transition is for documentation only.

7

Operational to Error is triggered if Libgcrypt detected an application error which can't be returned to the caller but still allows Libgcrypt to properly run. In the Error state all FIPS relevant interfaces return an error code.

8

Error to Shutdown is similar to the Operational to Shutdown transition (5).

9

Error to Fatal-Error is triggred if Libgrypt detects an fatal error while already being in Error state.

10

Fatal-Error to Shutdown is automatically entered by Libgcrypt after having reported the error.

11

Power-On to Shutdown is an artifical state to document that Libgcrypt has not ye been initializaed but the process is about to terminate.

12

Power-On to Fatal-Error will be triggerd if certain Libgcrypt functions are used without having reached the Init state.

13

Self-Test to Fatal-Error is triggred by severe errors in Libgcrypt while running self-tests.

14

Self-Test to Error is triggred by a failed self-test.

15

Operational to Fatal-Error is triggred if Libcrypt encountered a non-recoverable error.

16

Operational to Self-Test is triggred if the application requested to run the self-tests again.

17

Error to Self-Test is triggered if the application has requested to run self-tests to get to get back into operational state after an error.

Table B.2: FIPS mode state transitions