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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/arch/x86/purgatory
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/arch/x86/purgatory')
-rw-r--r--kernel/arch/x86/purgatory/Makefile30
-rw-r--r--kernel/arch/x86/purgatory/entry64.S101
-rw-r--r--kernel/arch/x86/purgatory/purgatory.c72
-rw-r--r--kernel/arch/x86/purgatory/setup-x86_64.S58
-rw-r--r--kernel/arch/x86/purgatory/sha256.c283
-rw-r--r--kernel/arch/x86/purgatory/sha256.h22
-rw-r--r--kernel/arch/x86/purgatory/stack.S19
-rw-r--r--kernel/arch/x86/purgatory/string.c13
8 files changed, 598 insertions, 0 deletions
diff --git a/kernel/arch/x86/purgatory/Makefile b/kernel/arch/x86/purgatory/Makefile
new file mode 100644
index 000000000..2c835e356
--- /dev/null
+++ b/kernel/arch/x86/purgatory/Makefile
@@ -0,0 +1,30 @@
+purgatory-y := purgatory.o stack.o setup-x86_$(BITS).o sha256.o entry64.o string.o
+
+targets += $(purgatory-y)
+PURGATORY_OBJS = $(addprefix $(obj)/,$(purgatory-y))
+
+LDFLAGS_purgatory.ro := -e purgatory_start -r --no-undefined -nostdlib -z nodefaultlib
+targets += purgatory.ro
+
+# Default KBUILD_CFLAGS can have -pg option set when FTRACE is enabled. That
+# in turn leaves some undefined symbols like __fentry__ in purgatory and not
+# sure how to relocate those. Like kexec-tools, use custom flags.
+
+KBUILD_CFLAGS := -fno-strict-aliasing -Wall -Wstrict-prototypes -fno-zero-initialized-in-bss -fno-builtin -ffreestanding -c -MD -Os -mcmodel=large
+KBUILD_CFLAGS += -m$(BITS)
+
+$(obj)/purgatory.ro: $(PURGATORY_OBJS) FORCE
+ $(call if_changed,ld)
+
+targets += kexec-purgatory.c
+
+CMD_BIN2C = $(objtree)/scripts/basic/bin2c
+quiet_cmd_bin2c = BIN2C $@
+ cmd_bin2c = $(CMD_BIN2C) kexec_purgatory < $< > $@
+
+$(obj)/kexec-purgatory.c: $(obj)/purgatory.ro FORCE
+ $(call if_changed,bin2c)
+ @:
+
+
+obj-$(CONFIG_KEXEC_FILE) += kexec-purgatory.o
diff --git a/kernel/arch/x86/purgatory/entry64.S b/kernel/arch/x86/purgatory/entry64.S
new file mode 100644
index 000000000..d1a4291d3
--- /dev/null
+++ b/kernel/arch/x86/purgatory/entry64.S
@@ -0,0 +1,101 @@
+/*
+ * Copyright (C) 2003,2004 Eric Biederman (ebiederm@xmission.com)
+ * Copyright (C) 2014 Red Hat Inc.
+
+ * Author(s): Vivek Goyal <vgoyal@redhat.com>
+ *
+ * This code has been taken from kexec-tools.
+ *
+ * This source code is licensed under the GNU General Public License,
+ * Version 2. See the file COPYING for more details.
+ */
+
+ .text
+ .balign 16
+ .code64
+ .globl entry64, entry64_regs
+
+
+entry64:
+ /* Setup a gdt that should be preserved */
+ lgdt gdt(%rip)
+
+ /* load the data segments */
+ movl $0x18, %eax /* data segment */
+ movl %eax, %ds
+ movl %eax, %es
+ movl %eax, %ss
+ movl %eax, %fs
+ movl %eax, %gs
+
+ /* Setup new stack */
+ leaq stack_init(%rip), %rsp
+ pushq $0x10 /* CS */
+ leaq new_cs_exit(%rip), %rax
+ pushq %rax
+ lretq
+new_cs_exit:
+
+ /* Load the registers */
+ movq rax(%rip), %rax
+ movq rbx(%rip), %rbx
+ movq rcx(%rip), %rcx
+ movq rdx(%rip), %rdx
+ movq rsi(%rip), %rsi
+ movq rdi(%rip), %rdi
+ movq rsp(%rip), %rsp
+ movq rbp(%rip), %rbp
+ movq r8(%rip), %r8
+ movq r9(%rip), %r9
+ movq r10(%rip), %r10
+ movq r11(%rip), %r11
+ movq r12(%rip), %r12
+ movq r13(%rip), %r13
+ movq r14(%rip), %r14
+ movq r15(%rip), %r15
+
+ /* Jump to the new code... */
+ jmpq *rip(%rip)
+
+ .section ".rodata"
+ .balign 4
+entry64_regs:
+rax: .quad 0x0
+rcx: .quad 0x0
+rdx: .quad 0x0
+rbx: .quad 0x0
+rsp: .quad 0x0
+rbp: .quad 0x0
+rsi: .quad 0x0
+rdi: .quad 0x0
+r8: .quad 0x0
+r9: .quad 0x0
+r10: .quad 0x0
+r11: .quad 0x0
+r12: .quad 0x0
+r13: .quad 0x0
+r14: .quad 0x0
+r15: .quad 0x0
+rip: .quad 0x0
+ .size entry64_regs, . - entry64_regs
+
+ /* GDT */
+ .section ".rodata"
+ .balign 16
+gdt:
+ /* 0x00 unusable segment
+ * 0x08 unused
+ * so use them as gdt ptr
+ */
+ .word gdt_end - gdt - 1
+ .quad gdt
+ .word 0, 0, 0
+
+ /* 0x10 4GB flat code segment */
+ .word 0xFFFF, 0x0000, 0x9A00, 0x00AF
+
+ /* 0x18 4GB flat data segment */
+ .word 0xFFFF, 0x0000, 0x9200, 0x00CF
+gdt_end:
+stack: .quad 0, 0
+stack_init:
diff --git a/kernel/arch/x86/purgatory/purgatory.c b/kernel/arch/x86/purgatory/purgatory.c
new file mode 100644
index 000000000..25e068ba3
--- /dev/null
+++ b/kernel/arch/x86/purgatory/purgatory.c
@@ -0,0 +1,72 @@
+/*
+ * purgatory: Runs between two kernels
+ *
+ * Copyright (C) 2014 Red Hat Inc.
+ *
+ * Author:
+ * Vivek Goyal <vgoyal@redhat.com>
+ *
+ * This source code is licensed under the GNU General Public License,
+ * Version 2. See the file COPYING for more details.
+ */
+
+#include "sha256.h"
+#include "../boot/string.h"
+
+struct sha_region {
+ unsigned long start;
+ unsigned long len;
+};
+
+unsigned long backup_dest = 0;
+unsigned long backup_src = 0;
+unsigned long backup_sz = 0;
+
+u8 sha256_digest[SHA256_DIGEST_SIZE] = { 0 };
+
+struct sha_region sha_regions[16] = {};
+
+/*
+ * On x86, second kernel requries first 640K of memory to boot. Copy
+ * first 640K to a backup region in reserved memory range so that second
+ * kernel can use first 640K.
+ */
+static int copy_backup_region(void)
+{
+ if (backup_dest)
+ memcpy((void *)backup_dest, (void *)backup_src, backup_sz);
+
+ return 0;
+}
+
+int verify_sha256_digest(void)
+{
+ struct sha_region *ptr, *end;
+ u8 digest[SHA256_DIGEST_SIZE];
+ struct sha256_state sctx;
+
+ sha256_init(&sctx);
+ end = &sha_regions[sizeof(sha_regions)/sizeof(sha_regions[0])];
+ for (ptr = sha_regions; ptr < end; ptr++)
+ sha256_update(&sctx, (uint8_t *)(ptr->start), ptr->len);
+
+ sha256_final(&sctx, digest);
+
+ if (memcmp(digest, sha256_digest, sizeof(digest)))
+ return 1;
+
+ return 0;
+}
+
+void purgatory(void)
+{
+ int ret;
+
+ ret = verify_sha256_digest();
+ if (ret) {
+ /* loop forever */
+ for (;;)
+ ;
+ }
+ copy_backup_region();
+}
diff --git a/kernel/arch/x86/purgatory/setup-x86_64.S b/kernel/arch/x86/purgatory/setup-x86_64.S
new file mode 100644
index 000000000..fe3c91ba1
--- /dev/null
+++ b/kernel/arch/x86/purgatory/setup-x86_64.S
@@ -0,0 +1,58 @@
+/*
+ * purgatory: setup code
+ *
+ * Copyright (C) 2003,2004 Eric Biederman (ebiederm@xmission.com)
+ * Copyright (C) 2014 Red Hat Inc.
+ *
+ * This code has been taken from kexec-tools.
+ *
+ * This source code is licensed under the GNU General Public License,
+ * Version 2. See the file COPYING for more details.
+ */
+
+ .text
+ .globl purgatory_start
+ .balign 16
+purgatory_start:
+ .code64
+
+ /* Load a gdt so I know what the segment registers are */
+ lgdt gdt(%rip)
+
+ /* load the data segments */
+ movl $0x18, %eax /* data segment */
+ movl %eax, %ds
+ movl %eax, %es
+ movl %eax, %ss
+ movl %eax, %fs
+ movl %eax, %gs
+
+ /* Setup a stack */
+ leaq lstack_end(%rip), %rsp
+
+ /* Call the C code */
+ call purgatory
+ jmp entry64
+
+ .section ".rodata"
+ .balign 16
+gdt: /* 0x00 unusable segment
+ * 0x08 unused
+ * so use them as the gdt ptr
+ */
+ .word gdt_end - gdt - 1
+ .quad gdt
+ .word 0, 0, 0
+
+ /* 0x10 4GB flat code segment */
+ .word 0xFFFF, 0x0000, 0x9A00, 0x00AF
+
+ /* 0x18 4GB flat data segment */
+ .word 0xFFFF, 0x0000, 0x9200, 0x00CF
+gdt_end:
+
+ .bss
+ .balign 4096
+lstack:
+ .skip 4096
+lstack_end:
diff --git a/kernel/arch/x86/purgatory/sha256.c b/kernel/arch/x86/purgatory/sha256.c
new file mode 100644
index 000000000..548ca675a
--- /dev/null
+++ b/kernel/arch/x86/purgatory/sha256.c
@@ -0,0 +1,283 @@
+/*
+ * SHA-256, as specified in
+ * http://csrc.nist.gov/groups/STM/cavp/documents/shs/sha256-384-512.pdf
+ *
+ * SHA-256 code by Jean-Luc Cooke <jlcooke@certainkey.com>.
+ *
+ * Copyright (c) Jean-Luc Cooke <jlcooke@certainkey.com>
+ * Copyright (c) Andrew McDonald <andrew@mcdonald.org.uk>
+ * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
+ * Copyright (c) 2014 Red Hat Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ */
+
+#include <linux/bitops.h>
+#include <asm/byteorder.h>
+#include "sha256.h"
+#include "../boot/string.h"
+
+static inline u32 Ch(u32 x, u32 y, u32 z)
+{
+ return z ^ (x & (y ^ z));
+}
+
+static inline u32 Maj(u32 x, u32 y, u32 z)
+{
+ return (x & y) | (z & (x | y));
+}
+
+#define e0(x) (ror32(x, 2) ^ ror32(x, 13) ^ ror32(x, 22))
+#define e1(x) (ror32(x, 6) ^ ror32(x, 11) ^ ror32(x, 25))
+#define s0(x) (ror32(x, 7) ^ ror32(x, 18) ^ (x >> 3))
+#define s1(x) (ror32(x, 17) ^ ror32(x, 19) ^ (x >> 10))
+
+static inline void LOAD_OP(int I, u32 *W, const u8 *input)
+{
+ W[I] = __be32_to_cpu(((__be32 *)(input))[I]);
+}
+
+static inline void BLEND_OP(int I, u32 *W)
+{
+ W[I] = s1(W[I-2]) + W[I-7] + s0(W[I-15]) + W[I-16];
+}
+
+static void sha256_transform(u32 *state, const u8 *input)
+{
+ u32 a, b, c, d, e, f, g, h, t1, t2;
+ u32 W[64];
+ int i;
+
+ /* load the input */
+ for (i = 0; i < 16; i++)
+ LOAD_OP(i, W, input);
+
+ /* now blend */
+ for (i = 16; i < 64; i++)
+ BLEND_OP(i, W);
+
+ /* load the state into our registers */
+ a = state[0]; b = state[1]; c = state[2]; d = state[3];
+ e = state[4]; f = state[5]; g = state[6]; h = state[7];
+
+ /* now iterate */
+ t1 = h + e1(e) + Ch(e, f, g) + 0x428a2f98 + W[0];
+ t2 = e0(a) + Maj(a, b, c); d += t1; h = t1 + t2;
+ t1 = g + e1(d) + Ch(d, e, f) + 0x71374491 + W[1];
+ t2 = e0(h) + Maj(h, a, b); c += t1; g = t1 + t2;
+ t1 = f + e1(c) + Ch(c, d, e) + 0xb5c0fbcf + W[2];
+ t2 = e0(g) + Maj(g, h, a); b += t1; f = t1 + t2;
+ t1 = e + e1(b) + Ch(b, c, d) + 0xe9b5dba5 + W[3];
+ t2 = e0(f) + Maj(f, g, h); a += t1; e = t1 + t2;
+ t1 = d + e1(a) + Ch(a, b, c) + 0x3956c25b + W[4];
+ t2 = e0(e) + Maj(e, f, g); h += t1; d = t1 + t2;
+ t1 = c + e1(h) + Ch(h, a, b) + 0x59f111f1 + W[5];
+ t2 = e0(d) + Maj(d, e, f); g += t1; c = t1 + t2;
+ t1 = b + e1(g) + Ch(g, h, a) + 0x923f82a4 + W[6];
+ t2 = e0(c) + Maj(c, d, e); f += t1; b = t1 + t2;
+ t1 = a + e1(f) + Ch(f, g, h) + 0xab1c5ed5 + W[7];
+ t2 = e0(b) + Maj(b, c, d); e += t1; a = t1 + t2;
+
+ t1 = h + e1(e) + Ch(e, f, g) + 0xd807aa98 + W[8];
+ t2 = e0(a) + Maj(a, b, c); d += t1; h = t1 + t2;
+ t1 = g + e1(d) + Ch(d, e, f) + 0x12835b01 + W[9];
+ t2 = e0(h) + Maj(h, a, b); c += t1; g = t1 + t2;
+ t1 = f + e1(c) + Ch(c, d, e) + 0x243185be + W[10];
+ t2 = e0(g) + Maj(g, h, a); b += t1; f = t1 + t2;
+ t1 = e + e1(b) + Ch(b, c, d) + 0x550c7dc3 + W[11];
+ t2 = e0(f) + Maj(f, g, h); a += t1; e = t1 + t2;
+ t1 = d + e1(a) + Ch(a, b, c) + 0x72be5d74 + W[12];
+ t2 = e0(e) + Maj(e, f, g); h += t1; d = t1 + t2;
+ t1 = c + e1(h) + Ch(h, a, b) + 0x80deb1fe + W[13];
+ t2 = e0(d) + Maj(d, e, f); g += t1; c = t1 + t2;
+ t1 = b + e1(g) + Ch(g, h, a) + 0x9bdc06a7 + W[14];
+ t2 = e0(c) + Maj(c, d, e); f += t1; b = t1 + t2;
+ t1 = a + e1(f) + Ch(f, g, h) + 0xc19bf174 + W[15];
+ t2 = e0(b) + Maj(b, c, d); e += t1; a = t1+t2;
+
+ t1 = h + e1(e) + Ch(e, f, g) + 0xe49b69c1 + W[16];
+ t2 = e0(a) + Maj(a, b, c); d += t1; h = t1+t2;
+ t1 = g + e1(d) + Ch(d, e, f) + 0xefbe4786 + W[17];
+ t2 = e0(h) + Maj(h, a, b); c += t1; g = t1+t2;
+ t1 = f + e1(c) + Ch(c, d, e) + 0x0fc19dc6 + W[18];
+ t2 = e0(g) + Maj(g, h, a); b += t1; f = t1+t2;
+ t1 = e + e1(b) + Ch(b, c, d) + 0x240ca1cc + W[19];
+ t2 = e0(f) + Maj(f, g, h); a += t1; e = t1+t2;
+ t1 = d + e1(a) + Ch(a, b, c) + 0x2de92c6f + W[20];
+ t2 = e0(e) + Maj(e, f, g); h += t1; d = t1+t2;
+ t1 = c + e1(h) + Ch(h, a, b) + 0x4a7484aa + W[21];
+ t2 = e0(d) + Maj(d, e, f); g += t1; c = t1+t2;
+ t1 = b + e1(g) + Ch(g, h, a) + 0x5cb0a9dc + W[22];
+ t2 = e0(c) + Maj(c, d, e); f += t1; b = t1+t2;
+ t1 = a + e1(f) + Ch(f, g, h) + 0x76f988da + W[23];
+ t2 = e0(b) + Maj(b, c, d); e += t1; a = t1+t2;
+
+ t1 = h + e1(e) + Ch(e, f, g) + 0x983e5152 + W[24];
+ t2 = e0(a) + Maj(a, b, c); d += t1; h = t1+t2;
+ t1 = g + e1(d) + Ch(d, e, f) + 0xa831c66d + W[25];
+ t2 = e0(h) + Maj(h, a, b); c += t1; g = t1+t2;
+ t1 = f + e1(c) + Ch(c, d, e) + 0xb00327c8 + W[26];
+ t2 = e0(g) + Maj(g, h, a); b += t1; f = t1+t2;
+ t1 = e + e1(b) + Ch(b, c, d) + 0xbf597fc7 + W[27];
+ t2 = e0(f) + Maj(f, g, h); a += t1; e = t1+t2;
+ t1 = d + e1(a) + Ch(a, b, c) + 0xc6e00bf3 + W[28];
+ t2 = e0(e) + Maj(e, f, g); h += t1; d = t1+t2;
+ t1 = c + e1(h) + Ch(h, a, b) + 0xd5a79147 + W[29];
+ t2 = e0(d) + Maj(d, e, f); g += t1; c = t1+t2;
+ t1 = b + e1(g) + Ch(g, h, a) + 0x06ca6351 + W[30];
+ t2 = e0(c) + Maj(c, d, e); f += t1; b = t1+t2;
+ t1 = a + e1(f) + Ch(f, g, h) + 0x14292967 + W[31];
+ t2 = e0(b) + Maj(b, c, d); e += t1; a = t1+t2;
+
+ t1 = h + e1(e) + Ch(e, f, g) + 0x27b70a85 + W[32];
+ t2 = e0(a) + Maj(a, b, c); d += t1; h = t1+t2;
+ t1 = g + e1(d) + Ch(d, e, f) + 0x2e1b2138 + W[33];
+ t2 = e0(h) + Maj(h, a, b); c += t1; g = t1+t2;
+ t1 = f + e1(c) + Ch(c, d, e) + 0x4d2c6dfc + W[34];
+ t2 = e0(g) + Maj(g, h, a); b += t1; f = t1+t2;
+ t1 = e + e1(b) + Ch(b, c, d) + 0x53380d13 + W[35];
+ t2 = e0(f) + Maj(f, g, h); a += t1; e = t1+t2;
+ t1 = d + e1(a) + Ch(a, b, c) + 0x650a7354 + W[36];
+ t2 = e0(e) + Maj(e, f, g); h += t1; d = t1+t2;
+ t1 = c + e1(h) + Ch(h, a, b) + 0x766a0abb + W[37];
+ t2 = e0(d) + Maj(d, e, f); g += t1; c = t1+t2;
+ t1 = b + e1(g) + Ch(g, h, a) + 0x81c2c92e + W[38];
+ t2 = e0(c) + Maj(c, d, e); f += t1; b = t1+t2;
+ t1 = a + e1(f) + Ch(f, g, h) + 0x92722c85 + W[39];
+ t2 = e0(b) + Maj(b, c, d); e += t1; a = t1+t2;
+
+ t1 = h + e1(e) + Ch(e, f, g) + 0xa2bfe8a1 + W[40];
+ t2 = e0(a) + Maj(a, b, c); d += t1; h = t1+t2;
+ t1 = g + e1(d) + Ch(d, e, f) + 0xa81a664b + W[41];
+ t2 = e0(h) + Maj(h, a, b); c += t1; g = t1+t2;
+ t1 = f + e1(c) + Ch(c, d, e) + 0xc24b8b70 + W[42];
+ t2 = e0(g) + Maj(g, h, a); b += t1; f = t1+t2;
+ t1 = e + e1(b) + Ch(b, c, d) + 0xc76c51a3 + W[43];
+ t2 = e0(f) + Maj(f, g, h); a += t1; e = t1+t2;
+ t1 = d + e1(a) + Ch(a, b, c) + 0xd192e819 + W[44];
+ t2 = e0(e) + Maj(e, f, g); h += t1; d = t1+t2;
+ t1 = c + e1(h) + Ch(h, a, b) + 0xd6990624 + W[45];
+ t2 = e0(d) + Maj(d, e, f); g += t1; c = t1+t2;
+ t1 = b + e1(g) + Ch(g, h, a) + 0xf40e3585 + W[46];
+ t2 = e0(c) + Maj(c, d, e); f += t1; b = t1+t2;
+ t1 = a + e1(f) + Ch(f, g, h) + 0x106aa070 + W[47];
+ t2 = e0(b) + Maj(b, c, d); e += t1; a = t1+t2;
+
+ t1 = h + e1(e) + Ch(e, f, g) + 0x19a4c116 + W[48];
+ t2 = e0(a) + Maj(a, b, c); d += t1; h = t1+t2;
+ t1 = g + e1(d) + Ch(d, e, f) + 0x1e376c08 + W[49];
+ t2 = e0(h) + Maj(h, a, b); c += t1; g = t1+t2;
+ t1 = f + e1(c) + Ch(c, d, e) + 0x2748774c + W[50];
+ t2 = e0(g) + Maj(g, h, a); b += t1; f = t1+t2;
+ t1 = e + e1(b) + Ch(b, c, d) + 0x34b0bcb5 + W[51];
+ t2 = e0(f) + Maj(f, g, h); a += t1; e = t1+t2;
+ t1 = d + e1(a) + Ch(a, b, c) + 0x391c0cb3 + W[52];
+ t2 = e0(e) + Maj(e, f, g); h += t1; d = t1+t2;
+ t1 = c + e1(h) + Ch(h, a, b) + 0x4ed8aa4a + W[53];
+ t2 = e0(d) + Maj(d, e, f); g += t1; c = t1+t2;
+ t1 = b + e1(g) + Ch(g, h, a) + 0x5b9cca4f + W[54];
+ t2 = e0(c) + Maj(c, d, e); f += t1; b = t1+t2;
+ t1 = a + e1(f) + Ch(f, g, h) + 0x682e6ff3 + W[55];
+ t2 = e0(b) + Maj(b, c, d); e += t1; a = t1+t2;
+
+ t1 = h + e1(e) + Ch(e, f, g) + 0x748f82ee + W[56];
+ t2 = e0(a) + Maj(a, b, c); d += t1; h = t1+t2;
+ t1 = g + e1(d) + Ch(d, e, f) + 0x78a5636f + W[57];
+ t2 = e0(h) + Maj(h, a, b); c += t1; g = t1+t2;
+ t1 = f + e1(c) + Ch(c, d, e) + 0x84c87814 + W[58];
+ t2 = e0(g) + Maj(g, h, a); b += t1; f = t1+t2;
+ t1 = e + e1(b) + Ch(b, c, d) + 0x8cc70208 + W[59];
+ t2 = e0(f) + Maj(f, g, h); a += t1; e = t1+t2;
+ t1 = d + e1(a) + Ch(a, b, c) + 0x90befffa + W[60];
+ t2 = e0(e) + Maj(e, f, g); h += t1; d = t1+t2;
+ t1 = c + e1(h) + Ch(h, a, b) + 0xa4506ceb + W[61];
+ t2 = e0(d) + Maj(d, e, f); g += t1; c = t1+t2;
+ t1 = b + e1(g) + Ch(g, h, a) + 0xbef9a3f7 + W[62];
+ t2 = e0(c) + Maj(c, d, e); f += t1; b = t1+t2;
+ t1 = a + e1(f) + Ch(f, g, h) + 0xc67178f2 + W[63];
+ t2 = e0(b) + Maj(b, c, d); e += t1; a = t1+t2;
+
+ state[0] += a; state[1] += b; state[2] += c; state[3] += d;
+ state[4] += e; state[5] += f; state[6] += g; state[7] += h;
+
+ /* clear any sensitive info... */
+ a = b = c = d = e = f = g = h = t1 = t2 = 0;
+ memset(W, 0, 64 * sizeof(u32));
+}
+
+int sha256_init(struct sha256_state *sctx)
+{
+ sctx->state[0] = SHA256_H0;
+ sctx->state[1] = SHA256_H1;
+ sctx->state[2] = SHA256_H2;
+ sctx->state[3] = SHA256_H3;
+ sctx->state[4] = SHA256_H4;
+ sctx->state[5] = SHA256_H5;
+ sctx->state[6] = SHA256_H6;
+ sctx->state[7] = SHA256_H7;
+ sctx->count = 0;
+
+ return 0;
+}
+
+int sha256_update(struct sha256_state *sctx, const u8 *data, unsigned int len)
+{
+ unsigned int partial, done;
+ const u8 *src;
+
+ partial = sctx->count & 0x3f;
+ sctx->count += len;
+ done = 0;
+ src = data;
+
+ if ((partial + len) > 63) {
+ if (partial) {
+ done = -partial;
+ memcpy(sctx->buf + partial, data, done + 64);
+ src = sctx->buf;
+ }
+
+ do {
+ sha256_transform(sctx->state, src);
+ done += 64;
+ src = data + done;
+ } while (done + 63 < len);
+
+ partial = 0;
+ }
+ memcpy(sctx->buf + partial, src, len - done);
+
+ return 0;
+}
+
+int sha256_final(struct sha256_state *sctx, u8 *out)
+{
+ __be32 *dst = (__be32 *)out;
+ __be64 bits;
+ unsigned int index, pad_len;
+ int i;
+ static const u8 padding[64] = { 0x80, };
+
+ /* Save number of bits */
+ bits = cpu_to_be64(sctx->count << 3);
+
+ /* Pad out to 56 mod 64. */
+ index = sctx->count & 0x3f;
+ pad_len = (index < 56) ? (56 - index) : ((64+56) - index);
+ sha256_update(sctx, padding, pad_len);
+
+ /* Append length (before padding) */
+ sha256_update(sctx, (const u8 *)&bits, sizeof(bits));
+
+ /* Store state in digest */
+ for (i = 0; i < 8; i++)
+ dst[i] = cpu_to_be32(sctx->state[i]);
+
+ /* Zeroize sensitive information. */
+ memset(sctx, 0, sizeof(*sctx));
+
+ return 0;
+}
diff --git a/kernel/arch/x86/purgatory/sha256.h b/kernel/arch/x86/purgatory/sha256.h
new file mode 100644
index 000000000..bd15a4127
--- /dev/null
+++ b/kernel/arch/x86/purgatory/sha256.h
@@ -0,0 +1,22 @@
+/*
+ * Copyright (C) 2014 Red Hat Inc.
+ *
+ * Author: Vivek Goyal <vgoyal@redhat.com>
+ *
+ * This source code is licensed under the GNU General Public License,
+ * Version 2. See the file COPYING for more details.
+ */
+
+#ifndef SHA256_H
+#define SHA256_H
+
+
+#include <linux/types.h>
+#include <crypto/sha.h>
+
+extern int sha256_init(struct sha256_state *sctx);
+extern int sha256_update(struct sha256_state *sctx, const u8 *input,
+ unsigned int length);
+extern int sha256_final(struct sha256_state *sctx, u8 *hash);
+
+#endif /* SHA256_H */
diff --git a/kernel/arch/x86/purgatory/stack.S b/kernel/arch/x86/purgatory/stack.S
new file mode 100644
index 000000000..3cefba1fe
--- /dev/null
+++ b/kernel/arch/x86/purgatory/stack.S
@@ -0,0 +1,19 @@
+/*
+ * purgatory: stack
+ *
+ * Copyright (C) 2014 Red Hat Inc.
+ *
+ * This source code is licensed under the GNU General Public License,
+ * Version 2. See the file COPYING for more details.
+ */
+
+ /* A stack for the loaded kernel.
+ * Seperate and in the data section so it can be prepopulated.
+ */
+ .data
+ .balign 4096
+ .globl stack, stack_end
+
+stack:
+ .skip 4096
+stack_end:
diff --git a/kernel/arch/x86/purgatory/string.c b/kernel/arch/x86/purgatory/string.c
new file mode 100644
index 000000000..d886b1fa3
--- /dev/null
+++ b/kernel/arch/x86/purgatory/string.c
@@ -0,0 +1,13 @@
+/*
+ * Simple string functions.
+ *
+ * Copyright (C) 2014 Red Hat Inc.
+ *
+ * Author:
+ * Vivek Goyal <vgoyal@redhat.com>
+ *
+ * This source code is licensed under the GNU General Public License,
+ * Version 2. See the file COPYING for more details.
+ */
+
+#include "../boot/string.c"