To be consistent with other VDSO functions, the function is called __kernel_getrandom()
__arch_chacha20_blocks_nostack() fonction is implemented basically with 32 bits operations. It performs 4 QUARTERROUND operations in parallele. There are enough registers to avoid using the stack:
On input: r3: output bytes r4: 32-byte key input r5: 8-byte counter input/output r6: number of 64-byte blocks to write to output
During operation: r0: counter of blocks (initialised with r6) r4: Value '4' after key has been read, used for indexing r6-r13: key r14-r15: block counter r16-r31: chacha state
At the end: r0, r6-r13: Zeroised r14-r31: Restored
Performance on powerpc 885 (using kernel selftest): ~# ./vdso_test_getrandom bench-single vdso: 2500000 times in 7.897495392 seconds libc: 2500000 times in 56.091632232 seconds syscall: 2500000 times in 55.704851989 seconds
Performance on powerpc 8321 (using kernel selftest): ~# ./vdso_test_getrandom bench-single vdso: 2500000 times in 2.017183250 seconds libc: 2500000 times in 13.088533630 seconds syscall: 2500000 times in 12.952458068 seconds
Signed-off-by: Christophe Leroy christophe.leroy@csgroup.eu --- arch/powerpc/Kconfig | 1 + arch/powerpc/include/asm/mman.h | 2 +- arch/powerpc/include/asm/vdso/getrandom.h | 67 +++++ arch/powerpc/include/asm/vdso/vsyscall.h | 6 + arch/powerpc/include/asm/vdso_datapage.h | 2 + arch/powerpc/kernel/asm-offsets.c | 1 + arch/powerpc/kernel/vdso/Makefile | 27 +- arch/powerpc/kernel/vdso/getrandom.S | 58 ++++ arch/powerpc/kernel/vdso/vdso32.lds.S | 1 + arch/powerpc/kernel/vdso/vdso64.lds.S | 1 + arch/powerpc/kernel/vdso/vgetrandom-chacha.S | 297 +++++++++++++++++++ arch/powerpc/kernel/vdso/vgetrandom.c | 14 + 12 files changed, 471 insertions(+), 6 deletions(-) create mode 100644 arch/powerpc/include/asm/vdso/getrandom.h create mode 100644 arch/powerpc/kernel/vdso/getrandom.S create mode 100644 arch/powerpc/kernel/vdso/vgetrandom-chacha.S create mode 100644 arch/powerpc/kernel/vdso/vgetrandom.c
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index d7b09b064a8a..b45452ac4a73 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -311,6 +311,7 @@ config PPC select SYSCTL_EXCEPTION_TRACE select THREAD_INFO_IN_TASK select TRACE_IRQFLAGS_SUPPORT + select VDSO_GETRANDOM # # Please keep this list sorted alphabetically. # diff --git a/arch/powerpc/include/asm/mman.h b/arch/powerpc/include/asm/mman.h index 17a77d47ed6d..42a51a993d94 100644 --- a/arch/powerpc/include/asm/mman.h +++ b/arch/powerpc/include/asm/mman.h @@ -6,7 +6,7 @@
#include <uapi/asm/mman.h>
-#ifdef CONFIG_PPC64 +#if defined(CONFIG_PPC64) && !defined(BUILD_VDSO)
#include <asm/cputable.h> #include <linux/mm.h> diff --git a/arch/powerpc/include/asm/vdso/getrandom.h b/arch/powerpc/include/asm/vdso/getrandom.h new file mode 100644 index 000000000000..b37e581b02cb --- /dev/null +++ b/arch/powerpc/include/asm/vdso/getrandom.h @@ -0,0 +1,67 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2024 Christophe Leroy christophe.leroy@csgroup.eu, CS GROUP France + */ +#ifndef _ASM_POWERPC_VDSO_GETRANDOM_H +#define _ASM_POWERPC_VDSO_GETRANDOM_H + +#ifndef __ASSEMBLY__ + +static __always_inline int do_syscall_3(const unsigned long _r0, const unsigned long _r3, + const unsigned long _r4, const unsigned long _r5) +{ + register long r0 asm("r0") = _r0; + register unsigned long r3 asm("r3") = _r3; + register unsigned long r4 asm("r4") = _r4; + register unsigned long r5 asm("r5") = _r5; + register int ret asm ("r3"); + + asm volatile( + " sc\n" + " bns+ 1f\n" + " neg %0, %0\n" + "1:\n" + : "=r" (ret), "+r" (r4), "+r" (r5), "+r" (r0) + : "r" (r3) + : "memory", "r6", "r7", "r8", "r9", "r10", "r11", "r12", "cr0", "ctr"); + + return ret; +} + +/** + * getrandom_syscall - Invoke the getrandom() syscall. + * @buffer: Destination buffer to fill with random bytes. + * @len: Size of @buffer in bytes. + * @flags: Zero or more GRND_* flags. + * Returns: The number of bytes written to @buffer, or a negative value indicating an error. + */ +static __always_inline ssize_t getrandom_syscall(void *buffer, size_t len, unsigned int flags) +{ + return do_syscall_3(__NR_getrandom, (unsigned long)buffer, + (unsigned long)len, (unsigned long)flags); +} + +static __always_inline struct vdso_rng_data *__arch_get_vdso_rng_data(void) +{ + BUILD_BUG(); +} + +ssize_t __c_kernel_getrandom(void *buffer, size_t len, unsigned int flags, void *opaque_state, + size_t opaque_len, const struct vdso_rng_data *vd); + +/** + * __arch_chacha20_blocks_nostack - Generate ChaCha20 stream without using the stack. + * @dst_bytes: Destination buffer to hold @nblocks * 64 bytes of output. + * @key: 32-byte input key. + * @counter: 8-byte counter, read on input and updated on return. + * @nblocks: Number of blocks to generate. + * + * Generates a given positive number of blocks of ChaCha20 output with nonce=0, and does not write + * to any stack or memory outside of the parameters passed to it, in order to mitigate stack data + * leaking into forked child processes. + */ +void __arch_chacha20_blocks_nostack(u8 *dst_bytes, const u32 *key, u32 *counter, size_t nblocks); + +#endif /* !__ASSEMBLY__ */ + +#endif /* _ASM_POWERPC_VDSO_GETRANDOM_H */ diff --git a/arch/powerpc/include/asm/vdso/vsyscall.h b/arch/powerpc/include/asm/vdso/vsyscall.h index 48cf23f1e273..92f480d8cc6d 100644 --- a/arch/powerpc/include/asm/vdso/vsyscall.h +++ b/arch/powerpc/include/asm/vdso/vsyscall.h @@ -17,6 +17,12 @@ struct vdso_data *__arch_get_k_vdso_data(void) } #define __arch_get_k_vdso_data __arch_get_k_vdso_data
+static __always_inline +struct vdso_rng_data *__arch_get_k_vdso_rng_data(void) +{ + return &vdso_data->rng_data; +} + /* The asm-generic header needs to be included after the definitions above */ #include <asm-generic/vdso/vsyscall.h>
diff --git a/arch/powerpc/include/asm/vdso_datapage.h b/arch/powerpc/include/asm/vdso_datapage.h index a585c8e538ff..e17500c5237e 100644 --- a/arch/powerpc/include/asm/vdso_datapage.h +++ b/arch/powerpc/include/asm/vdso_datapage.h @@ -83,6 +83,7 @@ struct vdso_arch_data { __u32 compat_syscall_map[SYSCALL_MAP_SIZE]; /* Map of compat syscalls */
struct vdso_data data[CS_BASES]; + struct vdso_rng_data rng_data; };
#else /* CONFIG_PPC64 */ @@ -95,6 +96,7 @@ struct vdso_arch_data { __u32 syscall_map[SYSCALL_MAP_SIZE]; /* Map of syscalls */ __u32 compat_syscall_map[0]; /* No compat syscalls on PPC32 */ struct vdso_data data[CS_BASES]; + struct vdso_rng_data rng_data; };
#endif /* CONFIG_PPC64 */ diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c index 23733282de4d..eedb2e04c785 100644 --- a/arch/powerpc/kernel/asm-offsets.c +++ b/arch/powerpc/kernel/asm-offsets.c @@ -335,6 +335,7 @@ int main(void)
/* datapage offsets for use by vdso */ OFFSET(VDSO_DATA_OFFSET, vdso_arch_data, data); + OFFSET(VDSO_RNG_DATA_OFFSET, vdso_arch_data, rng_data); OFFSET(CFG_TB_TICKS_PER_SEC, vdso_arch_data, tb_ticks_per_sec); #ifdef CONFIG_PPC64 OFFSET(CFG_ICACHE_BLOCKSZ, vdso_arch_data, icache_block_size); diff --git a/arch/powerpc/kernel/vdso/Makefile b/arch/powerpc/kernel/vdso/Makefile index cd4ed09864f0..9109677b2f39 100644 --- a/arch/powerpc/kernel/vdso/Makefile +++ b/arch/powerpc/kernel/vdso/Makefile @@ -8,6 +8,9 @@ include $(srctree)/lib/vdso/Makefile obj-vdso32 = sigtramp32-32.o gettimeofday-32.o datapage-32.o cacheflush-32.o note-32.o getcpu-32.o obj-vdso64 = sigtramp64-64.o gettimeofday-64.o datapage-64.o cacheflush-64.o note-64.o getcpu-64.o
+obj-vdso32 += getrandom-32.o vgetrandom-chacha-32.o +obj-vdso64 += getrandom-64.o vgetrandom-chacha-64.o + ifneq ($(c-gettimeofday-y),) CFLAGS_vgettimeofday-32.o += -include $(c-gettimeofday-y) CFLAGS_REMOVE_vgettimeofday-32.o += -mcmodel=medium -mabi=elfv1 -mabi=elfv2 -mcall-aixdesc @@ -24,6 +27,16 @@ ifneq ($(c-gettimeofday-y),) CFLAGS_vgettimeofday-64.o += $(call cc-option, -ffixed-r30) endif
+ifneq ($(c-getrandom-y),) + CFLAGS_vgetrandom-32.o += -include $(c-getrandom-y) + CFLAGS_REMOVE_vgetrandom-32.o += -mcmodel=medium -mabi=elfv1 -mabi=elfv2 -mcall-aixdesc + ifdef CONFIG_CC_IS_CLANG + CFLAGS_REMOVE_vgetrandom-32.o += -fno-stack-clash-protection + endif + CFLAGS_vgetrandom-64.o += -include $(c-getrandom-y) + CFLAGS_vgetrandom-64.o += $(call cc-option, -ffixed-r30) +endif + # Build rules
ifdef CROSS32_COMPILE @@ -32,13 +45,13 @@ else VDSOCC := $(CC) endif
-targets := $(obj-vdso32) vdso32.so.dbg vgettimeofday-32.o +targets := $(obj-vdso32) vdso32.so.dbg vgettimeofday-32.o vgetrandom-32.o targets += crtsavres-32.o obj-vdso32 := $(addprefix $(obj)/, $(obj-vdso32)) -targets += $(obj-vdso64) vdso64.so.dbg vgettimeofday-64.o +targets += $(obj-vdso64) vdso64.so.dbg vgettimeofday-64.o vgetrandom-64.o obj-vdso64 := $(addprefix $(obj)/, $(obj-vdso64))
-ccflags-y := -fno-common -fno-builtin +ccflags-y := -fno-common -fno-builtin -DBUILD_VDSO ccflags-y += $(DISABLE_LATENT_ENTROPY_PLUGIN) ccflags-y += $(call cc-option, -fno-stack-protector) ccflags-y += -DDISABLE_BRANCH_PROFILING @@ -64,9 +77,9 @@ targets += vdso64.lds CPPFLAGS_vdso64.lds += -P -C
# link rule for the .so file, .lds has to be first -$(obj)/vdso32.so.dbg: $(obj)/vdso32.lds $(obj-vdso32) $(obj)/vgettimeofday-32.o $(obj)/crtsavres-32.o FORCE +$(obj)/vdso32.so.dbg: $(obj)/vdso32.lds $(obj-vdso32) $(obj)/vgettimeofday-32.o $(obj)/vgetrandom-32.o $(obj)/crtsavres-32.o FORCE $(call if_changed,vdso32ld_and_check) -$(obj)/vdso64.so.dbg: $(obj)/vdso64.lds $(obj-vdso64) $(obj)/vgettimeofday-64.o FORCE +$(obj)/vdso64.so.dbg: $(obj)/vdso64.lds $(obj-vdso64) $(obj)/vgettimeofday-64.o $(obj)/vgetrandom-64.o FORCE $(call if_changed,vdso64ld_and_check)
# assembly rules for the .S files @@ -76,10 +89,14 @@ $(obj)/crtsavres-32.o: %-32.o: $(srctree)/arch/powerpc/lib/crtsavres.S FORCE $(call if_changed_dep,vdso32as) $(obj)/vgettimeofday-32.o: %-32.o: %.c FORCE $(call if_changed_dep,vdso32cc) +$(obj)/vgetrandom-32.o: %-32.o: %.c FORCE + $(call if_changed_dep,vdso32cc) $(obj-vdso64): %-64.o: %.S FORCE $(call if_changed_dep,vdso64as) $(obj)/vgettimeofday-64.o: %-64.o: %.c FORCE $(call if_changed_dep,cc_o_c) +$(obj)/vgetrandom-64.o: %-64.o: %.c FORCE + $(call if_changed_dep,cc_o_c)
# Generate VDSO offsets using helper script gen-vdso32sym := $(src)/gen_vdso32_offsets.sh diff --git a/arch/powerpc/kernel/vdso/getrandom.S b/arch/powerpc/kernel/vdso/getrandom.S new file mode 100644 index 000000000000..a957cd2b2b03 --- /dev/null +++ b/arch/powerpc/kernel/vdso/getrandom.S @@ -0,0 +1,58 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Userland implementation of getrandom() for processes + * for use in the vDSO + * + * Copyright (C) 2024 Christophe Leroy christophe.leroy@csgroup.eu, CS GROUP France + */ +#include <asm/processor.h> +#include <asm/ppc_asm.h> +#include <asm/vdso.h> +#include <asm/vdso_datapage.h> +#include <asm/asm-offsets.h> +#include <asm/unistd.h> + +/* + * The macro sets two stack frames, one for the caller and one for the callee + * because there are no requirement for the caller to set a stack frame when + * calling VDSO so it may have omitted to set one, especially on PPC64 + */ + +.macro cvdso_call funct + .cfi_startproc + PPC_STLU r1, -PPC_MIN_STKFRM(r1) + .cfi_adjust_cfa_offset PPC_MIN_STKFRM + mflr r0 + PPC_STLU r1, -PPC_MIN_STKFRM(r1) + .cfi_adjust_cfa_offset PPC_MIN_STKFRM + PPC_STL r0, PPC_MIN_STKFRM + PPC_LR_STKOFF(r1) + .cfi_rel_offset lr, PPC_MIN_STKFRM + PPC_LR_STKOFF +#ifdef __powerpc64__ + PPC_STL r2, PPC_MIN_STKFRM + STK_GOT(r1) + .cfi_rel_offset r2, PPC_MIN_STKFRM + STK_GOT +#endif + get_datapage r8 + addi r8, r8, VDSO_RNG_DATA_OFFSET + bl CFUNC(DOTSYM(\funct)) + PPC_LL r0, PPC_MIN_STKFRM + PPC_LR_STKOFF(r1) +#ifdef __powerpc64__ + PPC_LL r2, PPC_MIN_STKFRM + STK_GOT(r1) + .cfi_restore r2 +#endif + cmpwi r3, 0 + mtlr r0 + addi r1, r1, 2 * PPC_MIN_STKFRM + .cfi_restore lr + .cfi_def_cfa_offset 0 + crclr so + bgelr+ + crset so + neg r3, r3 + blr + .cfi_endproc +.endm + + .text +V_FUNCTION_BEGIN(__kernel_getrandom) + cvdso_call __c_kernel_getrandom +V_FUNCTION_END(__kernel_getrandom) diff --git a/arch/powerpc/kernel/vdso/vdso32.lds.S b/arch/powerpc/kernel/vdso/vdso32.lds.S index 8f57107000a2..7b41d5d256e8 100644 --- a/arch/powerpc/kernel/vdso/vdso32.lds.S +++ b/arch/powerpc/kernel/vdso/vdso32.lds.S @@ -130,6 +130,7 @@ VERSION #if defined(CONFIG_PPC64) || !defined(CONFIG_SMP) __kernel_getcpu; #endif + __kernel_getrandom;
local: *; }; diff --git a/arch/powerpc/kernel/vdso/vdso64.lds.S b/arch/powerpc/kernel/vdso/vdso64.lds.S index 400819258c06..9481e4b892ed 100644 --- a/arch/powerpc/kernel/vdso/vdso64.lds.S +++ b/arch/powerpc/kernel/vdso/vdso64.lds.S @@ -123,6 +123,7 @@ VERSION __kernel_sigtramp_rt64; __kernel_getcpu; __kernel_time; + __kernel_getrandom;
local: *; }; diff --git a/arch/powerpc/kernel/vdso/vgetrandom-chacha.S b/arch/powerpc/kernel/vdso/vgetrandom-chacha.S new file mode 100644 index 000000000000..5375bc5807e1 --- /dev/null +++ b/arch/powerpc/kernel/vdso/vgetrandom-chacha.S @@ -0,0 +1,297 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2024 Christophe Leroy christophe.leroy@csgroup.eu, CS GROUP France + */ + +#include <linux/linkage.h> + +#include <asm/ppc_asm.h> + +.macro quarterround4 a1 b1 c1 d1 a2 b2 c2 d2 a3 b3 c3 d3 a4 b4 c4 d4 + add \a1, \a1, \b1 + add \a2, \a2, \b2 + add \a3, \a3, \b3 + add \a4, \a4, \b4 + xor \d1, \d1, \a1 + xor \d2, \d2, \a2 + xor \d3, \d3, \a3 + xor \d4, \d4, \a4 + rotlwi \d1, \d1, 16 + rotlwi \d2, \d2, 16 + rotlwi \d3, \d3, 16 + rotlwi \d4, \d4, 16 + add \c1, \c1, \d1 + add \c2, \c2, \d2 + add \c3, \c3, \d3 + add \c4, \c4, \d4 + xor \b1, \b1, \c1 + xor \b2, \b2, \c2 + xor \b3, \b3, \c3 + xor \b4, \b4, \c4 + rotlwi \b1, \b1, 12 + rotlwi \b2, \b2, 12 + rotlwi \b3, \b3, 12 + rotlwi \b4, \b4, 12 + add \a1, \a1, \b1 + add \a2, \a2, \b2 + add \a3, \a3, \b3 + add \a4, \a4, \b4 + xor \d1, \d1, \a1 + xor \d2, \d2, \a2 + xor \d3, \d3, \a3 + xor \d4, \d4, \a4 + rotlwi \d1, \d1, 8 + rotlwi \d2, \d2, 8 + rotlwi \d3, \d3, 8 + rotlwi \d4, \d4, 8 + add \c1, \c1, \d1 + add \c2, \c2, \d2 + add \c3, \c3, \d3 + add \c4, \c4, \d4 + xor \b1, \b1, \c1 + xor \b2, \b2, \c2 + xor \b3, \b3, \c3 + xor \b4, \b4, \c4 + rotlwi \b1, \b1, 7 + rotlwi \b2, \b2, 7 + rotlwi \b3, \b3, 7 + rotlwi \b4, \b4, 7 +.endm + +#define QUARTERROUND4(a1,b1,c1,d1,a2,b2,c2,d2,a3,b3,c3,d3,a4,b4,c4,d4) \ + quarterround4 16+a1 16+b1 16+c1 16+d1 16+a2 16+b2 16+c2 16+d2 \ + 16+a3 16+b3 16+c3 16+d3 16+a4 16+b4 16+c4 16+d4 + +/* + * Very basic 32 bits implementation of ChaCha20. Produces a given positive number + * of blocks of output with a nonce of 0, taking an input key and 8-byte + * counter. Importantly does not spill to the stack. Its arguments are: + * + * r3: output bytes + * r4: 32-byte key input + * r5: 8-byte counter input/output + * r6: number of 64-byte blocks to write to output + * + * r0: counter of blocks (initialised with r6) + * r4: Value '4' after key has been read. + * r6-r13: key + * r14-r15 : counter + * r16-r31 : state + */ +SYM_FUNC_START(__arch_chacha20_blocks_nostack) +#ifdef __powerpc64__ + std r14,-144(r1) + std r15,-136(r1) + std r16,-128(r1) + std r17,-120(r1) + std r18,-112(r1) + std r19,-104(r1) + std r20,-96(r1) + std r21,-88(r1) + std r22,-80(r1) + std r23,-72(r1) + std r24,-64(r1) + std r25,-56(r1) + std r26,-48(r1) + std r27,-40(r1) + std r28,-32(r1) + std r29,-24(r1) + std r30,-16(r1) + std r31,-8(r1) +#else + stwu r1, -96(r1) +#if defined(CONFIG_CPU_LITTLE_ENDIAN) + stw r14,24(r1) + stw r15,28(r1) + stw r16,32(r1) + stw r17,36(r1) + stw r18,40(r1) + stw r19,44(r1) + stw r20,48(r1) + stw r21,52(r1) + stw r22,56(r1) + stw r23,60(r1) + stw r24,64(r1) + stw r25,68(r1) + stw r26,72(r1) + stw r27,76(r1) + stw r28,80(r1) + stw r29,84(r1) + stw r30,88(r1) + stw r31,92(r1) +#else + stmw r14, 24(r1) +#endif +#endif + mr r0, r6 + + li r31, 4 + + LWZX_LE r6, 0, r4 + LWZX_LE r7, r31, r4 + addi r4, r4, 8 + LWZX_LE r8, 0, r4 + LWZX_LE r9, r31, r4 + addi r4, r4, 8 + LWZX_LE r10, 0, r4 + LWZX_LE r11, r31, r4 + addi r4, r4, 8 + LWZX_LE r12, 0, r4 + LWZX_LE r13, r31, r4 + + li r4, 4 + + LWZX_LE r14, 0, r5 + LWZX_LE r15, r4, r5 +#ifdef __powerpc64__ + rldimi r14, r15, 32, 0 +#endif +.Lblock: + li r31, 10 + + lis r16, 0x6170 + lis r17, 0x3320 + lis r18, 0x7962 + lis r19, 0x6b20 + addi r16, r16, 0x7865 + addi r17, r17, 0x646e + addi r18, r18, 0x2d32 + addi r19, r19, 0x6574 + + mtctr r31 + + mr r20, r6 + mr r21, r7 + mr r22, r8 + mr r23, r9 + mr r24, r10 + mr r25, r11 + mr r26, r12 + mr r27, r13 + + mr r28, r14 + mr r29, r15 + li r30, 0 + li r31, 0 + +.Lpermute: + QUARTERROUND4( 0, 4, 8,12, 1, 5, 9,13, 2, 6,10,14, 3, 7,11,15) + QUARTERROUND4( 0, 5,10,15, 1, 6,11,12, 2, 7, 8,13, 3, 4, 9,14) + + bdnz .Lpermute + + addis r16, r16, 0x6170 + addis r17, r17, 0x3320 + addis r18, r18, 0x7962 + addis r19, r19, 0x6b20 + addi r16, r16, 0x7865 + addi r17, r17, 0x646e + addi r18, r18, 0x2d32 + addi r19, r19, 0x6574 + + add r20, r20, r6 + add r21, r21, r7 + add r22, r22, r8 + add r23, r23, r9 + add r24, r24, r10 + add r25, r25, r11 + add r26, r26, r12 + add r27, r27, r13 + + add r28, r28, r14 + add r29, r29, r15 + + STWX_LE r16, 0, r3 + STWX_LE r17, r4, r3 + addi r3, r3, 8 + STWX_LE r18, 0, r3 + STWX_LE r19, r4, r3 + addi r3, r3, 8 + STWX_LE r20, 0, r3 + STWX_LE r21, r4, r3 + addi r3, r3, 8 + STWX_LE r22, 0, r3 + STWX_LE r23, r4, r3 + addi r3, r3, 8 + STWX_LE r24, 0, r3 + STWX_LE r25, r4, r3 + addi r3, r3, 8 + STWX_LE r26, 0, r3 + STWX_LE r27, r4, r3 + addi r3, r3, 8 + STWX_LE r28, 0, r3 + STWX_LE r29, r4, r3 + addi r3, r3, 8 + STWX_LE r30, 0, r3 + STWX_LE r31, r4, r3 + addi r3, r3, 8 + +#ifdef __powerpc64__ + addi r14, r14, 1 + srdi r15, r14, 32 +#else + addic r14, r14, 1 + addze r15, r15 +#endif + + subic. r0, r0, 1 /* subi. can't use r0 as source */ + bne .Lblock + + STWX_LE r14, 0, r5 + STWX_LE r15, r4, r5 + + li r6, 0 + li r7, 0 + li r8, 0 + li r9, 0 + li r10, 0 + li r11, 0 + li r12, 0 + li r13, 0 + +#ifdef __powerpc64__ + ld r14,-144(r1) + ld r15,-136(r1) + ld r16,-128(r1) + ld r17,-120(r1) + ld r18,-112(r1) + ld r19,-104(r1) + ld r20,-96(r1) + ld r21,-88(r1) + ld r22,-80(r1) + ld r23,-72(r1) + ld r24,-64(r1) + ld r25,-56(r1) + ld r26,-48(r1) + ld r27,-40(r1) + ld r28,-32(r1) + ld r29,-24(r1) + ld r30,-16(r1) + ld r31,-8(r1) +#else +#if defined(CONFIG_CPU_LITTLE_ENDIAN) + lwz r14,24(r1) + lwz r15,28(r1) + lwz r16,32(r1) + lwz r17,36(r1) + lwz r18,40(r1) + lwz r19,44(r1) + lwz r20,48(r1) + lwz r21,52(r1) + lwz r22,56(r1) + lwz r23,60(r1) + lwz r24,64(r1) + lwz r25,68(r1) + lwz r26,72(r1) + lwz r27,76(r1) + lwz r28,80(r1) + lwz r29,84(r1) + lwz r30,88(r1) + lwz r31,92(r1) +#else + lmw r14, 24(r1) +#endif + addi r1, r1, 96 +#endif + blr +SYM_FUNC_END(__arch_chacha20_blocks_nostack) diff --git a/arch/powerpc/kernel/vdso/vgetrandom.c b/arch/powerpc/kernel/vdso/vgetrandom.c new file mode 100644 index 000000000000..5f855d45fb7b --- /dev/null +++ b/arch/powerpc/kernel/vdso/vgetrandom.c @@ -0,0 +1,14 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Powerpc userspace implementation of getrandom() + * + * Copyright (C) 2024 Christophe Leroy christophe.leroy@csgroup.eu, CS GROUP France + */ +#include <linux/time.h> +#include <linux/types.h> + +ssize_t __c_kernel_getrandom(void *buffer, size_t len, unsigned int flags, void *opaque_state, + size_t opaque_len, const struct vdso_rng_data *vd) +{ + return __cvdso_getrandom_data(vd, buffer, len, flags, opaque_state, opaque_len); +}