455 lines
11 KiB
C
455 lines
11 KiB
C
/*
|
|
* Perform FIPS Integrity test on Kernel Crypto API
|
|
*
|
|
* At build time, hmac(sha256) of crypto code, avaiable in different ELF sections
|
|
* of vmlinux file, is generated. vmlinux file is updated with built-time hmac
|
|
* in a read-only data variable, so that it is available at run-time
|
|
*
|
|
* At run time, hmac(sha256) is again calculated using crypto bytes of a running
|
|
* kernel.
|
|
* Run time hmac is compared to built time hmac to verify the integrity.
|
|
*
|
|
*
|
|
* Author : Rohit Kothari (r.kothari@samsung.com)
|
|
* Date : 11 Feb 2014
|
|
*
|
|
* Copyright (c) 2014 Samsung Electronics
|
|
*
|
|
*/
|
|
|
|
#include <linux/crypto.h>
|
|
#include <linux/kallsyms.h>
|
|
#include <linux/err.h>
|
|
#include <linux/scatterlist.h>
|
|
#include "internal.h" /* For Functional test macros */
|
|
|
|
static const char *
|
|
symtab[][3] = {{".text", "first_crypto_text", "last_crypto_text" },
|
|
{".rodata", "first_crypto_rodata", "last_crypto_rodata"},
|
|
{".init.text", "first_crypto_init", "last_crypto_init" },
|
|
{".exit.text", "first_crypto_exit", "last_crypto_exit" },
|
|
{"asm.text", "first_crypto_asm_text", "last_crypto_asm_text" },
|
|
{"asm.rodata", "first_crypto_asm_rodata", "last_crypto_asm_rodata"},
|
|
{"asm.init.text", "first_crypto_asm_init", "last_crypto_asm_init" },
|
|
{"asm.exit.text", "first_crypto_asm_exit", "last_crypto_asm_exit" }};
|
|
|
|
extern const char * get_builtime_crypto_hmac(void);
|
|
|
|
#ifdef FIPS_DEBUG
|
|
static int
|
|
dump_bytes(const char * section_name, const char * first_symbol, const char * last_symbol)
|
|
{
|
|
u8 * start_addr = (u8 *) kallsyms_lookup_name (first_symbol);
|
|
u8 * end_addr = (u8 *) kallsyms_lookup_name (last_symbol);
|
|
|
|
if (!start_addr || !end_addr || start_addr >= end_addr)
|
|
{
|
|
printk(KERN_ERR "FIPS(%s): Error Invalid Addresses in Section : %s, Start_Addr : %p , End_Addr : %p",
|
|
__FUNCTION__,section_name, start_addr, end_addr);
|
|
return -1;
|
|
}
|
|
|
|
printk(KERN_INFO "FIPS CRYPTO RUNTIME : Section - %s, %s : %p, %s : %p \n", section_name, first_symbol, start_addr, last_symbol, end_addr);
|
|
|
|
print_hex_dump_bytes ("FIPS CRYPTO RUNTIME : ",DUMP_PREFIX_NONE, start_addr, end_addr - start_addr);
|
|
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
|
|
static int
|
|
query_symbol_addresses (const char * first_symbol, const char * last_symbol,
|
|
unsigned long * start_addr,unsigned long * end_addr)
|
|
{
|
|
unsigned long start = kallsyms_lookup_name (first_symbol);
|
|
unsigned long end = kallsyms_lookup_name (last_symbol);
|
|
|
|
#ifdef FIPS_DEBUG
|
|
printk(KERN_INFO "FIPS CRYPTO RUNTIME : %s : %p, %s : %p\n", first_symbol, (u8*)start, last_symbol, (u8*)end);
|
|
#endif
|
|
|
|
if (!start || !end || start >= end)
|
|
{
|
|
printk(KERN_ERR "FIPS(%s): Error Invalid Addresses.", __FUNCTION__);
|
|
return -1;
|
|
}
|
|
|
|
*start_addr = start;
|
|
*end_addr = end;
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
static int
|
|
init_hash (struct hash_desc * desc)
|
|
{
|
|
struct crypto_hash * tfm = NULL;
|
|
int ret = -1;
|
|
|
|
/* Same as build time */
|
|
const unsigned char * key = "The quick brown fox jumps over the lazy dog";
|
|
|
|
tfm = crypto_alloc_hash ("hmac(sha256)", 0, 0);
|
|
|
|
if (IS_ERR(tfm)) {
|
|
printk(KERN_ERR "FIPS(%s): integ failed to allocate tfm %ld", __FUNCTION__, PTR_ERR(tfm));
|
|
return -1;
|
|
}
|
|
|
|
ret = crypto_hash_setkey (tfm, key, strlen(key));
|
|
|
|
if (ret) {
|
|
printk(KERN_ERR "FIPS(%s): fail at crypto_hash_setkey", __FUNCTION__);
|
|
return -1;
|
|
}
|
|
|
|
desc->tfm = tfm;
|
|
desc->flags = 0;
|
|
|
|
ret = crypto_hash_init (desc);
|
|
|
|
if (ret) {
|
|
printk(KERN_ERR "FIPS(%s): fail at crypto_hash_init", __FUNCTION__);
|
|
return -1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
finalize_hash (struct hash_desc *desc, unsigned char * out, unsigned int out_size)
|
|
{
|
|
int ret = -1;
|
|
|
|
if (!desc || !desc->tfm || !out || !out_size)
|
|
{
|
|
printk(KERN_ERR "FIPS(%s): Invalid args", __FUNCTION__);
|
|
return ret;
|
|
}
|
|
|
|
if (crypto_hash_digestsize(desc->tfm) > out_size)
|
|
{
|
|
printk(KERN_ERR "FIPS(%s): Not enough space for digest", __FUNCTION__);
|
|
return ret;
|
|
}
|
|
|
|
ret = crypto_hash_final (desc, out);
|
|
|
|
if (ret)
|
|
{
|
|
printk(KERN_ERR "FIPS(%s): crypto_hash_final failed", __FUNCTION__);
|
|
return -1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
update_hash (struct hash_desc * desc, unsigned char * start_addr, unsigned int size)
|
|
{
|
|
struct scatterlist sg;
|
|
unsigned char * buf = NULL;
|
|
unsigned char * cur = NULL;
|
|
unsigned int bytes_remaining;
|
|
unsigned int bytes;
|
|
int ret = -1;
|
|
#if FIPS_FUNC_TEST == 2
|
|
static int total = 0;
|
|
#endif
|
|
|
|
buf = kmalloc (PAGE_SIZE, GFP_KERNEL);
|
|
|
|
if (!buf)
|
|
{
|
|
printk(KERN_ERR "FIPS(%s): kmalloc failed", __FUNCTION__);
|
|
return ret;
|
|
}
|
|
|
|
bytes_remaining = size;
|
|
cur = start_addr;
|
|
|
|
while (bytes_remaining > 0)
|
|
{
|
|
if (bytes_remaining >= PAGE_SIZE)
|
|
bytes = PAGE_SIZE;
|
|
else
|
|
bytes = bytes_remaining;
|
|
|
|
memcpy (buf, cur, bytes);
|
|
|
|
sg_init_one (&sg, buf, bytes);
|
|
|
|
#if FIPS_FUNC_TEST == 2
|
|
if (total == 0)
|
|
{
|
|
printk(KERN_INFO "FIPS : Failing Integrity Test");
|
|
buf[bytes / 2] += 1;
|
|
}
|
|
#endif
|
|
|
|
ret = crypto_hash_update (desc, &sg, bytes);
|
|
|
|
if (ret)
|
|
{
|
|
printk(KERN_ERR "FIPS(%s): crypto_hash_update failed", __FUNCTION__);
|
|
kfree(buf);
|
|
buf = 0;
|
|
return -1;
|
|
}
|
|
|
|
cur += bytes;
|
|
|
|
bytes_remaining -= bytes;
|
|
|
|
#if FIPS_FUNC_TEST == 2
|
|
total += bytes;
|
|
#endif
|
|
}
|
|
|
|
//printk(KERN_INFO "FIPS : total bytes = %d\n", total);
|
|
|
|
if (buf)
|
|
{
|
|
kfree(buf);
|
|
buf = 0;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
int
|
|
do_integrity_check (void)
|
|
{
|
|
int i,rows, err;
|
|
unsigned long start_addr = 0;
|
|
unsigned long end_addr = 0;
|
|
unsigned char runtime_hmac[32];
|
|
struct hash_desc desc;
|
|
const char * builtime_hmac = 0;
|
|
unsigned int size = 0;
|
|
|
|
err = init_hash (&desc);
|
|
|
|
if (err)
|
|
{
|
|
printk (KERN_ERR "FIPS(%s): init_hash failed", __FUNCTION__);
|
|
return -1;
|
|
}
|
|
|
|
rows = (unsigned int) sizeof (symtab) / sizeof (symtab[0]);
|
|
|
|
for (i = 0; i < rows; i++)
|
|
{
|
|
err = query_symbol_addresses (symtab[i][1], symtab[i][2], &start_addr, &end_addr);
|
|
|
|
if (err)
|
|
{
|
|
printk (KERN_ERR "FIPS(%s): Error to get start / end addresses", __FUNCTION__);
|
|
crypto_free_hash (desc.tfm);
|
|
return -1;
|
|
}
|
|
|
|
#ifdef FIPS_DEBUG
|
|
dump_bytes(symtab[i][0], symtab[i][1], symtab[i][2]);
|
|
#endif
|
|
|
|
size = end_addr - start_addr;
|
|
|
|
err = update_hash (&desc, (unsigned char *)start_addr, size);
|
|
|
|
if (err)
|
|
{
|
|
printk (KERN_ERR "FIPS(%s): Error to update hash", __FUNCTION__);
|
|
crypto_free_hash (desc.tfm);
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
err = finalize_hash (&desc, runtime_hmac, sizeof(runtime_hmac));
|
|
|
|
crypto_free_hash (desc.tfm);
|
|
|
|
if (err)
|
|
{
|
|
printk (KERN_ERR "FIPS(%s): Error in finalize", __FUNCTION__);
|
|
return -1;
|
|
}
|
|
|
|
|
|
builtime_hmac = get_builtime_crypto_hmac();
|
|
|
|
if (!builtime_hmac)
|
|
{
|
|
printk (KERN_ERR "FIPS(%s): Unable to retrieve builtime_hmac", __FUNCTION__);
|
|
return -1;
|
|
}
|
|
|
|
#ifdef FIPS_DEBUG
|
|
print_hex_dump_bytes ("FIPS CRYPTO RUNTIME : runtime hmac = ",DUMP_PREFIX_NONE, runtime_hmac, sizeof(runtime_hmac));
|
|
print_hex_dump_bytes ("FIPS CRYPTO RUNTIME : builtime_hmac = ",DUMP_PREFIX_NONE, builtime_hmac , sizeof(runtime_hmac));
|
|
#endif
|
|
|
|
if (!memcmp (builtime_hmac, runtime_hmac, sizeof(runtime_hmac)))
|
|
{
|
|
printk (KERN_INFO "FIPS: Integrity Check Passed");
|
|
return 0;
|
|
}
|
|
else
|
|
{
|
|
printk (KERN_ERR "FIPS(%s): Integrity Check Failed", __FUNCTION__);
|
|
set_in_fips_err();
|
|
return -1;
|
|
}
|
|
|
|
return -1;
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(do_integrity_check);
|
|
|
|
#ifdef CONFIG_CRYPTO_FIPS_OLD_INTEGRITY_CHECK
|
|
/*
|
|
* Integrity check code for crypto module.
|
|
*
|
|
* 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 <crypto/hash.h>
|
|
#include <crypto/sha.h>
|
|
#include <linux/err.h>
|
|
#include <linux/scatterlist.h>
|
|
#include <asm-generic/sections.h>
|
|
#include <linux/vmalloc.h>
|
|
#include <linux/slab.h>
|
|
|
|
#include "internal.h"
|
|
|
|
static bool need_integrity_check = true;
|
|
extern long integrity_mem_reservoir;
|
|
//extern void free_bootmem(unsigned long addr, unsigned long size);
|
|
|
|
void do_integrity_check(void)
|
|
{
|
|
u8 *rbuf = 0;
|
|
u32 len;
|
|
u8 hmac[SHA256_DIGEST_SIZE];
|
|
struct hash_desc desc;
|
|
struct scatterlist sg;
|
|
u8 *key = "12345678";
|
|
int i, step_len = PAGE_SIZE, err;
|
|
u8 *pAllocBuf = 0;
|
|
|
|
printk(KERN_INFO "FIPS: integrity start\n");
|
|
|
|
if (unlikely(!need_integrity_check || in_fips_err())) {
|
|
printk(KERN_INFO "FIPS: integrity check not needed\n");
|
|
return;
|
|
}
|
|
rbuf = (u8*)phys_to_virt((unsigned long)CONFIG_CRYPTO_FIPS_INTEG_COPY_ADDRESS);
|
|
|
|
if (*((u32 *) &rbuf[36]) != 0x016F2818) {
|
|
printk(KERN_ERR "FIPS: invalid zImage magic number.");
|
|
set_in_fips_err();
|
|
goto err1;
|
|
}
|
|
|
|
if (*(u32 *) &rbuf[44] <= *(u32 *) &rbuf[40]) {
|
|
printk(KERN_ERR "FIPS: invalid zImage calculated len");
|
|
set_in_fips_err();
|
|
goto err1;
|
|
}
|
|
|
|
len = *(u32 *) &rbuf[44] - *(u32 *) &rbuf[40];
|
|
|
|
printk(KERN_INFO "FIPS: integrity actual zImageLen = %d\n", len);
|
|
printk(KERN_INFO "FIPS: do kernel integrity check address: %lx \n", (unsigned long)rbuf);
|
|
|
|
desc.tfm = crypto_alloc_hash("hmac(sha256)", 0, 0);
|
|
|
|
if (IS_ERR(desc.tfm)) {
|
|
printk(KERN_ERR "FIPS: integ failed to allocate tfm %ld\n",
|
|
PTR_ERR(desc.tfm));
|
|
set_in_fips_err();
|
|
goto err1;
|
|
}
|
|
#if FIPS_FUNC_TEST == 2
|
|
rbuf[1024] = rbuf[1024] + 1;
|
|
#endif
|
|
crypto_hash_setkey(desc.tfm, key, strlen(key));
|
|
|
|
pAllocBuf = kmalloc(step_len,GFP_KERNEL);
|
|
if (!pAllocBuf) {
|
|
printk(KERN_INFO "Fail to alloc memory, length %d\n", step_len);
|
|
set_in_fips_err();
|
|
goto err1;
|
|
}
|
|
|
|
err = crypto_hash_init(&desc);
|
|
if (err) {
|
|
printk(KERN_INFO "fail at crypto_hash_init\n");
|
|
set_in_fips_err();
|
|
kfree(pAllocBuf);
|
|
goto err1;
|
|
}
|
|
|
|
for (i = 0; i < len; i += step_len) {
|
|
|
|
//last is reached
|
|
if (i + step_len >= len - 1) {
|
|
memcpy(pAllocBuf, &rbuf[i], len - i);
|
|
sg_init_one(&sg, pAllocBuf, len - i);
|
|
err = crypto_hash_update(&desc, &sg, len - i);
|
|
if (err) {
|
|
printk(KERN_INFO "Fail to crypto_hash_update1\n");
|
|
set_in_fips_err();
|
|
goto err;
|
|
}
|
|
err = crypto_hash_final(&desc, hmac);
|
|
if (err) {
|
|
printk(KERN_INFO "Fail to crypto_hash_final\n");
|
|
set_in_fips_err();
|
|
goto err;
|
|
}
|
|
} else {
|
|
memcpy(pAllocBuf, &rbuf[i], step_len);
|
|
sg_init_one(&sg, pAllocBuf, step_len);
|
|
err = crypto_hash_update(&desc, &sg, step_len);
|
|
|
|
if (err) {
|
|
printk(KERN_INFO "Fail to crypto_hash_update\n");
|
|
set_in_fips_err();
|
|
goto err;
|
|
}
|
|
}
|
|
}
|
|
#if FIPS_FUNC_TEST == 2
|
|
rbuf[1024] = rbuf[1024] - 1;
|
|
#endif
|
|
if (!strncmp(hmac, &rbuf[len], SHA256_DIGEST_SIZE)) {
|
|
printk(KERN_INFO "FIPS: integrity check passed\n");
|
|
} else {
|
|
printk(KERN_ERR "FIPS: integrity check failed. hmac:%lx, buf:%lx.\n",(long) hmac, (long)rbuf[len] );
|
|
set_in_fips_err();
|
|
}
|
|
|
|
err:
|
|
kfree(pAllocBuf);
|
|
crypto_free_hash(desc.tfm);
|
|
err1:
|
|
need_integrity_check = false;
|
|
|
|
/* if(integrity_mem_reservoir != 0) {
|
|
printk(KERN_NOTICE "FIPS free integrity_mem_reservoir = %ld\n", integrity_mem_reservoir);
|
|
free_bootmem((unsigned long)CONFIG_CRYPTO_FIPS_INTEG_COPY_ADDRESS, integrity_mem_reservoir);
|
|
}
|
|
*/
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(do_integrity_check);
|
|
#endif //CONFIG_CRYPTO_FIPS_OLD_INTEGRITY_CHECK
|