Backport 3.6: ssl_fork_server RNG testing#10666
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gilles-peskine-arm wants to merge 9 commits intoMbed-TLS:mbedtls-3.6from
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Backport 3.6: ssl_fork_server RNG testing#10666gilles-peskine-arm wants to merge 9 commits intoMbed-TLS:mbedtls-3.6from
gilles-peskine-arm wants to merge 9 commits intoMbed-TLS:mbedtls-3.6from
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Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
`ssl_fork_server` reseeds its RNG, so in a build with a nonvolatile seed, it re-reads the seed file midway. If the client also rewrites the seed file while the server is running, that causes the test conditions to not reflect real-world conditions for the server. Fix this by running `ssl_fork_server` in its own directory when we're asserting properties of the random generator. This was a relatively easy way to separate the client seed file from the server seed file, since the seed file name `"seedfile"` is not configurable at runtime. This mostly matters for builds with no actual entropy source, only an NV seed. Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Assert that when two clients connect to ssl_fork_server, they see different random values from the server. This validates that each child process has its own random generator state. Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Assert that when two clients connect to ssl_fork_server, they see different ephemeral public keys from the server. This validates that each child process has its own random generator state. Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Run some of `ssl-opt.sh` on builds with only an NV seed as the entropy source. There isn't much that isn't already covered by unit tests, but do test that it works in a "real" program. In particular, run `ssl_fork_server` which has a peculiar challenge since its RNG state is replicated. Test both builds with `MBEDTLS_USE_PSA_CRYPTO` enabled (via the `full` config) and `MBEDTLS_USE_PSA_CRYPTO` disabled (by minimally tweaking the default config), as this makes a difference to RNG usage. Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
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| @@ -2041,6 +2076,10 @@ cleanup() { | |||
| rm -f $CLI_OUT $SRV_OUT $PXY_OUT $SESSION | |||
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Fairly minor, however if I've understood correctly this cleanup is only run under the conditions on line 2273 ie. INT TERM HUP. Would it be better to to either add normal exit to the exit conditions or change the test -s as currently the seedfile will be reused for each test. If the test corrupts or overwrites it possibly could effect the result.
…ient random values Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
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Fix a bug introduced in "Fix temporary directory left behind on normal exit" that caused the exit code of `ssl-opt.sh` to be 1 on success. Also, when exiting on a trapped signal, re-raise the signal rather than exiting with status 1. Also, on failure, where we report the number of failures through the exit code, clamp the exit code to 125 to avoid confusion with standard values. Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
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Test that
ssl_fork_serverhas a different RNG state in each client. Fixes #10664.Needs preceding PR: Mbed-TLS/mbedtls-framework#296
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