Simple ECDSA support

[tomato42]

Support for ECDSA authentication from server side

(first part of the full ECDSA support, #52, reworking of #196 to make review easier)

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This change is 

[lgtm-com]

This pull request introduces 5 alerts and fixes 1 when merging 2087e80 into 401712c - view on LGTM.com

new alerts:

• 3 for Unused import
• 1 for Unused local variable
• 1 for 'import *' may pollute namespace

fixed alerts:

• 1 for Membership test with a non-container

[lgtm-com]

This pull request fixes 1 alert when merging 1fd2cc1 into 401712c - view on LGTM.com

fixed alerts:

• 1 for Membership test with a non-container

[lgtm-com]

This pull request fixes 1 alert when merging 2b6c6da into 401712c - view on LGTM.com

fixed alerts:

• 1 for Membership test with a non-container

[lgtm-com]

This pull request fixes 1 alert when merging 0199b2d into 401712c - view on LGTM.com

fixed alerts:

• 1 for Membership test with a non-container

[ansasaki]

Reviewed 7 of 7 files at r1, 5 of 5 files at r2, 4 of 4 files at r3, 1 of 1 files at r4, 4 of 4 files at r5, 3 of 3 files at r6, 9 of 9 files at r7.
Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @tomato42)

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tlslite/utils/python_key.py, line 112 at r5 (raw file):

    def _parse_ecc_ssleay(data):
        """
        Parse binary structure of the old SSLeay file fromat used by OpenSSL.

s/fromat/format/

[tomato42]

Reviewable status: 13 of 26 files reviewed, 1 unresolved discussion (waiting on @ansasaki)

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tlslite/utils/python_key.py, line 112 at r5 (raw file):

Previously, ansasaki (Anderson Sasaki) wrote…

s/fromat/format/

Done.

[lgtm-com]

This pull request fixes 1 alert when merging d44800d into 401712c - view on LGTM.com

fixed alerts:

• 1 for Membership test with a non-container

[ansasaki]

Reviewed 13 of 13 files at r8, 3 of 3 files at r9, 9 of 9 files at r10.
Reviewable status: complete! all files reviewed, all discussions resolved

[ansasaki]

To be honest, in this review I couldn't check all the changes (for example the hardcoded keys, cipher suites allowed for each TLS version, etc.). I'm relying on the results of the added tests, which seems to cover the changes.

[tomato42]

To be honest, in this review I couldn't check all the changes (for example the hardcoded keys, cipher suites allowed for each TLS version, etc.). I'm relying on the results of the added tests, which seems to cover the changes.

that's the idea: the tests should show that the code works :)

the proper test coverage will come with tlsfuzzer/tlsfuzzer#543 and related issues

thanks!