tpm.dev.tutorials/PythonExamples/quote.md

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# Quote
This example demonstrates the use of ESAPI.quote
The code will:
* setup the ESAPI interface
* send a TPM_STARTUP clear command
* request a quote using the given attestation key, pcrs and extradata
* unmarshal the returned data structures and print these as a python dict and convert to JSON and pretty print
then as a bonus example
* generate a random number from the TPM and use that as the extra data to the quote
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## Setup and Variables
The following code might need to be modified for you local setup
```python3
tcti_to_use = None
attestation_key_handle = 0x810100AA
pcrs_to_quote = "sha256:0,1,2,3"
extradata_to_use = b"Ian12345"
```
## 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 pretty printed JSON structure will be shown.
## Example Output
The following is example output:
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```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
att= <tpm2_pytss.types.TPMS_ATTEST object at 0x7f0bebf19070>
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ae= <class 'dict'>
{'attested': {'pcrDigest': '38723a2e5e8a17aa7950dc008209944e898f69a7bd10a23c839d341e935fd5ca', 'pcrSelect': [{'hash': 'sha256', 'pcrSelect': [0, 1, 2, 3]}]}, 'clockInfo': {'clock': 313399693, 'resetCount': 24, 'restartCount': 0, 'safe': 1}, 'extraData': '49616e3132333435', 'firmwareVersion': [538513443, 1455670], 'magic': 4283712327, 'qualifiedSigner': '000bff3ea118be81e7f10ead098c900b93c885785e828bf27d824a87add847b5ec56', 'type': 'attest_quote'}
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{
"attested": {
"pcrDigest": "38723a2e5e8a17aa7950dc008209944e898f69a7bd10a23c839d341e935fd5ca",
"pcrSelect": [
{
"hash": "sha256",
"pcrSelect": [
0,
1,
2,
3
]
}
]
},
"clockInfo": {
"clock": 313399693,
"resetCount": 24,
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"restartCount": 0,
"safe": 1
},
"extraData": "49616e3132333435",
"firmwareVersion": [
538513443,
1455670
],
"magic": 4283712327,
"qualifiedSigner": "000bff3ea118be81e7f10ead098c900b93c885785e828bf27d824a87add847b5ec56",
"type": "attest_quote"
}
With randomly generated extra data: 0c830dd1a9dd50c0
ae2= <class 'dict'>
{'attested': {'pcrDigest': '38723a2e5e8a17aa7950dc008209944e898f69a7bd10a23c839d341e935fd5ca', 'pcrSelect': [{'hash': 'sha256', 'pcrSelect': [0, 1, 2, 3]}]}, 'clockInfo': {'clock': 313399694, 'resetCount': 24, 'restartCount': 0, 'safe': 1}, 'extraData': '30633833306464316139646435306330', 'firmwareVersion': [538513443, 1455670], 'magic': 4283712327, 'qualifiedSigner': '000bff3ea118be81e7f10ead098c900b93c885785e828bf27d824a87add847b5ec56', '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.