Fix -fsanitize=undefined diagnostics #6
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Fixes the following diagnostics: ``` bigint.c:631:39: runtime error: left shift of 162 by 24 places cannot be represented in type 'int' sha1.c:124:42: runtime error: left shift of 152 by 24 places cannot be represented in type 'int' ``` Directs the sanitizer not to instrument the function where this diagnostic otherwise occurs: ``` crypto_misc.c:131:5: runtime error: load of address 0x7ffd83a8633c with insufficient space for an object of type 'unsigned char' ``` .. this function deliberately reads memory in a way that is undefined under the C standard, but is a semi-recognized technique to maybe supplement a CSPRNG entropy pool; blindly removing it is the riskier option, a la https://www.debian.org/security/2008/dsa-1571 These changes fix all the problems seen in axtls when running the testsuite of a popular embedded python implementation on a linux amd64 desktop with gcc 8.3.0 -fsanitize=undefined.
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Fixes the following diagnostics:
Directs the sanitizer not to instrument the function where this diagnostic otherwise occurs:
.. this function deliberately reads memory in a way that is undefined under the C standard, but is a semi-recognized technique to maybe supplement a CSPRNG entropy pool; blindly removing it is the riskier option, a la https://www.debian.org/security/2008/dsa-1571
These changes fix all the problems seen in axtls when running the testsuite of a popular embedded python implementation on a linux amd64 desktop with gcc 8.3.0 -fsanitize=undefined.
I don't know your branching policy in this repo, so feel free to close if this is not something you're interested in taking, or let me know which branch I should be working relative to so I can re-spin if necessary.