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externals/mbedtls/tests/data_files/dir-maxpath/Readme.txt

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+These certificates form a very long chain, used to test the
+MBEDTLS_X509_MAX_INT_CA limit.
+
+NN.key is the private key of certificate NN.crt.
+
+The root is 00.crt and N+1.crt is a child of N.crt.
+
+File cNN.pem contains the chain NN.crt to 00.crt.
+
+Those certificates were generated by tests/data_files/dir-maxpath/long.sh.