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| author | Hsin-Yi Wang <hsinyi@chromium.org> | 2019-08-23 14:24:51 +0800 |
|---|---|---|
| committer | Will Deacon <will@kernel.org> | 2019-08-23 16:39:26 +0100 |
| commit | 428826f5358c922dc378830a1717b682c0823160 (patch) | |
| tree | c6487033843f52641f669cd90275466f4fff16f9 /include/linux/random.h | |
| parent | e112b032a72c78f15d0c803c5dc6be444c2e6c66 (diff) | |
| download | lwn-428826f5358c922dc378830a1717b682c0823160.tar.gz lwn-428826f5358c922dc378830a1717b682c0823160.zip | |
fdt: add support for rng-seed
Introducing a chosen node, rng-seed, which is an entropy that can be
passed to kernel called very early to increase initial device
randomness. Bootloader should provide this entropy and the value is
read from /chosen/rng-seed in DT.
Obtain of_fdt_crc32 for CRC check after early_init_dt_scan_nodes(),
since early_init_dt_scan_chosen() would modify fdt to erase rng-seed.
Add a new interface add_bootloader_randomness() for rng-seed use case.
Depends on whether the seed is trustworthy, rng seed would be passed to
add_hwgenerator_randomness(). Otherwise it would be passed to
add_device_randomness(). Decision is controlled by kernel config
RANDOM_TRUST_BOOTLOADER.
Signed-off-by: Hsin-Yi Wang <hsinyi@chromium.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Theodore Ts'o <tytso@mit.edu> # drivers/char/random.c
Signed-off-by: Will Deacon <will@kernel.org>
Diffstat (limited to 'include/linux/random.h')
| -rw-r--r-- | include/linux/random.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/include/linux/random.h b/include/linux/random.h index 1f7dced2bba6..f189c927fdea 100644 --- a/include/linux/random.h +++ b/include/linux/random.h @@ -19,6 +19,7 @@ struct random_ready_callback { }; extern void add_device_randomness(const void *, unsigned int); +extern void add_bootloader_randomness(const void *, unsigned int); #if defined(LATENT_ENTROPY_PLUGIN) && !defined(__CHECKER__) static inline void add_latent_entropy(void) |