Re: [PATCH] aarch64: vdso: Wire up getrandom() vDSO implementation

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 





Le 27/08/2024 à 15:39, Adhemerval Zanella Netto a écrit :
[Vous ne recevez pas souvent de courriers de adhemerval.zanella@xxxxxxxxxx. Découvrez pourquoi ceci est important à https://aka.ms/LearnAboutSenderIdentification ]

On 27/08/24 10:34, Jason A. Donenfeld wrote:
On Tue, Aug 27, 2024 at 10:17:18AM -0300, Adhemerval Zanella Netto wrote:


On 26/08/24 17:27, Jason A. Donenfeld wrote:
Hi Adhemerval,

Thanks for posting this! Exciting to have it here.

Just some small nits for now:

On Mon, Aug 26, 2024 at 06:10:40PM +0000, Adhemerval Zanella wrote:
+static __always_inline ssize_t getrandom_syscall(void *buffer, size_t len, unsigned int flags)
+{
+  register long int x8 asm ("x8") = __NR_getrandom;
+  register long int x0 asm ("x0") = (long int) buffer;
+  register long int x1 asm ("x1") = (long int) len;
+  register long int x2 asm ("x2") = (long int) flags;

Usually it's written just as `long` or `unsigned long`, and likewise
with the cast. Also, no space after the cast.

Ack.


+#define __VDSO_RND_DATA_OFFSET  480

This is the size of the data currently there?

Yes, I used the same strategy x86 did.


  #include <asm/page.h>
  #include <asm/vdso.h>
  #include <asm-generic/vmlinux.lds.h>
+#include <vdso/datapage.h>
+#include <asm/vdso/vsyscall.h>

Possible to keep the asm/ together?

Ack.


+ * ARM64 ChaCha20 implementation meant for vDSO.  Produces a given positive
+ * number of blocks of output with nonnce 0, taking an input key and 8-bytes

nonnce -> nonce

Ack.


-ARCH ?= $(shell echo $(uname_M) | sed -e s/i.86/x86/ -e s/x86_64/x86/)
+ARCH ?= $(shell echo $(uname_M) | sed -e s/i.86/x86/ -e s/x86_64/x86/ -e s/aarch64.*/arm64/)
  SODIUM := $(shell pkg-config --libs libsodium 2>/dev/null)

  TEST_GEN_PROGS := vdso_test_gettimeofday
@@ -11,7 +11,7 @@ ifeq ($(ARCH),$(filter $(ARCH),x86 x86_64))
  TEST_GEN_PROGS += vdso_standalone_test_x86
  endif
  TEST_GEN_PROGS += vdso_test_correctness
-ifeq ($(uname_M),x86_64)
+ifeq ($(uname_M), $(filter x86_64 aarch64, $(uname_M)))
  TEST_GEN_PROGS += vdso_test_getrandom
  ifneq ($(SODIUM),)
  TEST_GEN_PROGS += vdso_test_chacha

You'll need to add the symlink to get the chacha selftest running:

   $ ln -s ../../../arch/arm64/kernel/vdso tools/arch/arm64/vdso
   $ git add tools/arch/arm64/vdso

Also, can you confirm that the chacha selftest runs and works?

Yes, last time I has to built it manually since the Makefile machinery seem
to be broken even on x86_64.  In a Ubuntu vm I have:

tools/testing/selftests/vDSO$ make
   CC       vdso_test_gettimeofday
   CC       vdso_test_getcpu
   CC       vdso_test_abi
   CC       vdso_test_clock_getres
   CC       vdso_standalone_test_x86
   CC       vdso_test_correctness
   CC       vdso_test_getrandom
   CC       vdso_test_chacha
In file included from /home/azanella/Projects/linux/linux-git/include/linux/limits.h:7,
                  from /usr/include/x86_64-linux-gnu/bits/local_lim.h:38,
                  from /usr/include/x86_64-linux-gnu/bits/posix1_lim.h:161,
                  from /usr/include/limits.h:195,
                  from /usr/lib/gcc/x86_64-linux-gnu/13/include/limits.h:205,
                  from /usr/lib/gcc/x86_64-linux-gnu/13/include/syslimits.h:7,
                  from /usr/lib/gcc/x86_64-linux-gnu/13/include/limits.h:34,
                  from /usr/include/sodium/export.h:7,
                  from /usr/include/sodium/crypto_stream_chacha20.h:14,
                  from vdso_test_chacha.c:6:
/usr/include/x86_64-linux-gnu/bits/xopen_lim.h:99:6: error: missing binary operator before token "("
    99 | # if INT_MAX == 32767
       |      ^~~~~~~
/usr/include/x86_64-linux-gnu/bits/xopen_lim.h:102:7: error: missing binary operator before token "("
   102 | #  if INT_MAX == 2147483647
       |       ^~~~~~~
/usr/include/x86_64-linux-gnu/bits/xopen_lim.h:126:6: error: missing binary operator before token "("
   126 | # if LONG_MAX == 2147483647
       |      ^~~~~~~~
make: *** [../lib.mk:222: /home/azanella/Projects/linux/linux-git/tools/testing/selftests/vDSO/vdso_test_chacha] Error 1

You get that even with the latest random.git? I thought Christophe's
patch fixed that, but maybe not and I should just remove the dependency
on the sodium header instead.

On x86_64 I tested with Linux master.  With random.git it is a different issue:

linux-git/tools/testing/selftests/vDSO$ make
   CC       vdso_test_gettimeofday
   CC       vdso_test_getcpu
   CC       vdso_test_abi
   CC       vdso_test_clock_getres
   CC       vdso_standalone_test_x86
   CC       vdso_test_correctness
   CC       vdso_test_getrandom
   CC       vdso_test_chacha
/usr/bin/ld: /tmp/ccKpjnSM.o: in function `main':
vdso_test_chacha.c:(.text+0x276): undefined reference to `crypto_stream_chacha20'
collect2: error: ld returned 1 exit status

If I move -lsodium to the end of the compiler command it works.



Try a "make clean" maybe ?

I have Fedora 38 and no build problem with latest random tree:

$ make V=1
gcc -std=gnu99 -D_GNU_SOURCE= vdso_test_gettimeofday.c parse_vdso.c -o /home/chleroy/linux-powerpc/tools/testing/selftests/vDSO/vdso_test_gettimeofday gcc -std=gnu99 -D_GNU_SOURCE= vdso_test_getcpu.c parse_vdso.c -o /home/chleroy/linux-powerpc/tools/testing/selftests/vDSO/vdso_test_getcpu gcc -std=gnu99 -D_GNU_SOURCE= vdso_test_abi.c parse_vdso.c -o /home/chleroy/linux-powerpc/tools/testing/selftests/vDSO/vdso_test_abi gcc -std=gnu99 -D_GNU_SOURCE= vdso_test_clock_getres.c -o /home/chleroy/linux-powerpc/tools/testing/selftests/vDSO/vdso_test_clock_getres gcc -std=gnu99 -D_GNU_SOURCE= -nostdlib -fno-asynchronous-unwind-tables -fno-stack-protector vdso_standalone_test_x86.c parse_vdso.c -o /home/chleroy/linux-powerpc/tools/testing/selftests/vDSO/vdso_standalone_test_x86 gcc -std=gnu99 -D_GNU_SOURCE= -ldl vdso_test_correctness.c -o /home/chleroy/linux-powerpc/tools/testing/selftests/vDSO/vdso_test_correctness gcc -std=gnu99 -D_GNU_SOURCE= -isystem /home/chleroy/linux-powerpc/tools/testing/selftests/../../../tools/include -isystem /home/chleroy/linux-powerpc/tools/testing/selftests/../../../include/uapi vdso_test_getrandom.c parse_vdso.c -o /home/chleroy/linux-powerpc/tools/testing/selftests/vDSO/vdso_test_getrandom gcc -std=gnu99 -D_GNU_SOURCE= -idirafter /home/chleroy/linux-powerpc/tools/testing/selftests/../../../tools/include -idirafter /home/chleroy/linux-powerpc/tools/testing/selftests/../../../arch/x86/include -idirafter /home/chleroy/linux-powerpc/tools/testing/selftests/../../../include -D__ASSEMBLY__ -DBULID_VDSO -DCONFIG_FUNCTION_ALIGNMENT=0 -Wa,--noexecstack -lsodium vdso_test_chacha.c /home/chleroy/linux-powerpc/tools/testing/selftests/../../../tools/arch/x86/vdso/vgetrandom-chacha.S -o /home/chleroy/linux-powerpc/tools/testing/selftests/vDSO/vdso_test_chacha
$




[Index of Archives]     [Kernel]     [Gnu Classpath]     [Gnu Crypto]     [DM Crypt]     [Netfilter]     [Bugtraq]
  Powered by Linux