added random numbers and updated text

PythonExamples/README.md

@@ -14,4 +14,24 @@ Each example can be run just by typing `python3 example.py`
 
 Each example has an accompanying description as markdown file, plus annotated code.
 
-   * [quote]
+   * [randomnumber]
+   * [quote]
+
+## Notes on TCTI Errors
+
+When an `ESAPI` object is created it will print out errors as it searches for a suitable TPM devices. For example:
+
+```bash
+~/tpm.dev.tutorials/PythonExamples$ python3 randomnumber.py 
+ERROR:tcti:src/tss2-tcti/tcti-device.c:442:Tss2_Tcti_Device_Init() Failed to open specified TCTI device file /dev/tpmrm0: No such file or directory 
+ERROR:tcti:src/tss2-tcti/tctildr-dl.c:154:tcti_from_file() Could not initialize TCTI file: libtss2-tcti-device.so.0 
+ERROR:tcti:src/tss2-tcti/tcti-device.c:442:Tss2_Tcti_Device_Init() Failed to open specified TCTI device file /dev/tpm0: No such file or directory 
+ERROR:tcti:src/tss2-tcti/tctildr-dl.c:154:tcti_from_file() Could not initialize TCTI file: libtss2-tcti-device.so.0 
+ERROR:tcti:src/tss2-tcti/tcti-swtpm.c:222:tcti_control_command() Control command failed with error: 1 
+ERROR:tcti:src/tss2-tcti/tcti-swtpm.c:330:tcti_swtpm_set_locality() Failed to set locality: 0xa000a 
+WARNING:tcti:src/tss2-tcti/tcti-swtpm.c:599:Tss2_Tcti_Swtpm_Init() Could not set locality via control channel: 0xa000a 
+ERROR:tcti:src/tss2-tcti/tctildr-dl.c:154:tcti_from_file() Could not initialize TCTI file: libtss2-tcti-swtpm.so.0 
+type is  <class 'tpm2_pytss.types.TPM2B_DIGEST'>
+r    is  a10ab7558675a56c
+as hex   11604288967829464428
+```

PythonExamples/quote.md

@@ -26,18 +26,12 @@ To run type `python3 quote.py`
 
 Errors might be generated as the pytss libraries search for a suitable TPM device. If everything is successful then a pretty printed JSON structure will be shown.
 
-## Example Output
+## Output
+
+The following is example output:
 
 ```bash
-~/tpm.dev.tutorials/PythonExamples$ python3 quote.py 
-ERROR:tcti:src/tss2-tcti/tcti-device.c:442:Tss2_Tcti_Device_Init() Failed to open specified TCTI device file /dev/tpmrm0: No such file or directory 
-ERROR:tcti:src/tss2-tcti/tctildr-dl.c:154:tcti_from_file() Could not initialize TCTI file: libtss2-tcti-device.so.0 
-ERROR:tcti:src/tss2-tcti/tcti-device.c:442:Tss2_Tcti_Device_Init() Failed to open specified TCTI device file /dev/tpm0: No such file or directory 
-ERROR:tcti:src/tss2-tcti/tctildr-dl.c:154:tcti_from_file() Could not initialize TCTI file: libtss2-tcti-device.so.0 
-ERROR:tcti:src/tss2-tcti/tcti-swtpm.c:222:tcti_control_command() Control command failed with error: 1 
-ERROR:tcti:src/tss2-tcti/tcti-swtpm.c:330:tcti_swtpm_set_locality() Failed to set locality: 0xa000a 
-WARNING:tcti:src/tss2-tcti/tcti-swtpm.c:599:Tss2_Tcti_Swtpm_Init() Could not set locality via control channel: 0xa000a 
-ERROR:tcti:src/tss2-tcti/tctildr-dl.c:154:tcti_from_file() Could not initialize TCTI file: libtss2-tcti-swtpm.so.0 
+~/tpm.dev.tutorials/PythonExamples$ python3 quote.py
 att= <tpm2_pytss.types.TPMS_ATTEST object at 0x7f5fb10419d0>
 ae= <class 'dict'> 
  {'attested': {'pcrDigest': '38723a2e5e8a17aa7950dc008209944e898f69a7bd10a23c839d341e935fd5ca', 'pcrSelect': [{'hash': 'sha256', 'pcrSelect': [0, 1, 2, 3]}]}, 'clockInfo': {'clock': 308418200, 'resetCount': 22, 'restartCount': 0, 'safe': 1}, 'extraData': '49616e3132333435', 'firmwareVersion': [538513443, 1455670], 'magic': 4283712327, 'qualifiedSigner': '000bff3ea118be81e7f10ead098c900b93c885785e828bf27d824a87add847b5ec56', 'type': 'attest_quote'}
@@ -73,4 +67,6 @@ ae= <class 'dict'>
     "type": "attest_quote"
 }
 
-```
+```
+
+The *magic number* of the quote is returned as an integer `4283712327` this corresponds to the better known TPM returned byte sequence `FF544347` in hex.

PythonExamples/randomnumber.md

@@ -0,0 +1,30 @@
+# Quote
+
+This example demonstrates the use of ESAPI.get_random
+
+The code will:
+
+   * setup the ESAPI interface
+   * send a TPM_STARTUP clear command
+   * request 8 random numbers from the TPM
+   * print out the result
+
+## Setup and Variables
+
+No specific setup is required. You may wish to change the number of bytes returned in the `get_random` call. 
+
+## Running
+
+To run type `python3 quote.py`
+
+Errors might be generated as the pytss libraries search for a suitable TPM device. If everything is successful then a random number will be shown.
+
+## Output
+
+```bash
+~/tpm.dev.tutorials/PythonExamples$ python3 randomnumber.py 
+type is  <class 'tpm2_pytss.types.TPM2B_DIGEST'>
+r    is  a10ab7558675a56c
+as int   11604288967829464428
+
+```

PythonExamples/randomnumber.py

@@ -0,0 +1,31 @@
+#
+# Import the tpm2_pytss libraries 
+#
+
+from tpm2_pytss import *
+
+#
+# Make a connection to a TPM and use the ESAPI interface
+# tcti=None means that the pytss libraries will search for an available TCTI
+#
+#
+# When this is run, then as the various TCTI interfaces are searched errors are written if those interfaces are not foud
+#
+
+tpm = ESAPI(tcti=None)
+
+# 
+# Send a startup message, just in case (actually this is because I'm using the IBM SW TPM and haven't started it properly)
+#
+
+tpm.startup(TPM2_SU.CLEAR)
+
+#
+# Now to make the quote and return the attested values and signature
+#
+
+r = tpm.get_random( 8 )
+
+print("type is ",type(r))
+print("r    is ",str(r))
+print("as int  ",int(str(r),16))