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AWS Signature Version 4


The AWS Signature Version 4 (SigV4) Library is a standalone library for generating authentication headers and signatures according to the specifications of the AWS Signature Version 4 signing process. This library can be used by applications to interact with AWS services that require SigV4 authentication using HTTP. This library has no dependencies on any library other than the standard C library.

This library has gone through code quality checks including verification that no function has a GNU Complexity score over 8, and checks against deviations from mandatory rules in the MISRA coding standard. Deviations from the MISRA C:2012 guidelines are documented under MISRA Deviations. This library has also undergone static code analysis using Coverity static analysis, and validation of memory safety through the CBMC automated reasoning tool.

This library can be freely used and is distributed under the MIT Open Source License.


Code Size of AWS SigV4 library (example generated with GCC for ARM Cortex-M)
FileWith -O1 OptimizationWith -Os Optimization
Total estimates5.6K4.7K
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