env: Remove CONFIG_ENV_AES support

This support has been deprecated since v2017.09 due to security issues.
We now remove this support.

Signed-off-by: Tom Rini <trini@konsulko.com>
This commit is contained in:
Tom Rini 2017-11-14 08:39:35 -05:00
parent 042de609ed
commit c6831c74a9
8 changed files with 2 additions and 180 deletions

8
env/Kconfig vendored
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@ -360,14 +360,6 @@ config ENV_IS_IN_UBI
endchoice
config ENV_AES
bool "AES-128 encryption for stored environment (DEPRECATED)"
help
Enable this to have the on-device stored environment be encrypted
with AES-128. The implementation here however has security
complications and is not recommended for use. Please see
CVE-2017-3225 and CVE-2017-3226 for more details.
config ENV_FAT_INTERFACE
string "Name of the block device for the environment"
depends on ENV_IS_IN_FAT

61
env/common.c vendored
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@ -103,52 +103,6 @@ int set_default_vars(int nvars, char * const vars[])
H_NOCLEAR | H_INTERACTIVE, 0, nvars, vars);
}
#ifdef CONFIG_ENV_AES
#include <uboot_aes.h>
/**
* env_aes_cbc_get_key() - Get AES-128-CBC key for the environment
*
* This function shall return 16-byte array containing AES-128 key used
* to encrypt and decrypt the environment. This function must be overridden
* by the implementer as otherwise the environment encryption will not
* work.
*/
__weak uint8_t *env_aes_cbc_get_key(void)
{
return NULL;
}
static int env_aes_cbc_crypt(env_t *env, const int enc)
{
unsigned char *data = env->data;
uint8_t *key;
uint8_t key_exp[AES_EXPAND_KEY_LENGTH];
uint32_t aes_blocks;
key = env_aes_cbc_get_key();
if (!key)
return -EINVAL;
/* First we expand the key. */
aes_expand_key(key, key_exp);
/* Calculate the number of AES blocks to encrypt. */
aes_blocks = ENV_SIZE / AES_KEY_LENGTH;
if (enc)
aes_cbc_encrypt_blocks(key_exp, data, data, aes_blocks);
else
aes_cbc_decrypt_blocks(key_exp, data, data, aes_blocks);
return 0;
}
#else
static inline int env_aes_cbc_crypt(env_t *env, const int enc)
{
return 0;
}
#endif
/*
* Check if CRC is valid and (if yes) import the environment.
* Note that "buf" may or may not be aligned.
@ -156,7 +110,6 @@ static inline int env_aes_cbc_crypt(env_t *env, const int enc)
int env_import(const char *buf, int check)
{
env_t *ep = (env_t *)buf;
int ret;
if (check) {
uint32_t crc;
@ -169,14 +122,6 @@ int env_import(const char *buf, int check)
}
}
/* Decrypt the env if desired. */
ret = env_aes_cbc_crypt(ep, 0);
if (ret) {
pr_err("Failed to decrypt env!\n");
set_default_env("!import failed");
return ret;
}
if (himport_r(&env_htab, (char *)ep->data, ENV_SIZE, '\0', 0, 0,
0, NULL)) {
gd->flags |= GD_FLG_ENV_READY;
@ -242,7 +187,6 @@ int env_export(env_t *env_out)
{
char *res;
ssize_t len;
int ret;
res = (char *)env_out->data;
len = hexport_r(&env_htab, '\0', 0, &res, ENV_SIZE, 0, NULL);
@ -251,11 +195,6 @@ int env_export(env_t *env_out)
return 1;
}
/* Encrypt the env if desired. */
ret = env_aes_cbc_crypt(env_out, 1);
if (ret)
return ret;
env_out->crc = crc32(0, env_out->data, ENV_SIZE);
#ifdef CONFIG_SYS_REDUNDAND_ENVIRONMENT

View File

@ -143,12 +143,7 @@ extern unsigned long nand_env_oob_offset;
# define ENV_HEADER_SIZE (sizeof(uint32_t))
#endif
#ifdef CONFIG_ENV_AES
/* Make sure the payload is multiple of AES block size */
#define ENV_SIZE ((CONFIG_ENV_SIZE - ENV_HEADER_SIZE) & ~(16 - 1))
#else
#define ENV_SIZE (CONFIG_ENV_SIZE - ENV_HEADER_SIZE)
#endif
typedef struct environment_s {
uint32_t crc; /* CRC32 over data bytes */
@ -156,12 +151,7 @@ typedef struct environment_s {
unsigned char flags; /* active/obsolete flags */
#endif
unsigned char data[ENV_SIZE]; /* Environment data */
} env_t
#ifdef CONFIG_ENV_AES
/* Make sure the env is aligned to block size. */
__attribute__((aligned(16)))
#endif
;
} env_t;
#ifdef ENV_IS_EMBEDDED
extern env_t environment;

2
tools/env/Makefile vendored
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@ -25,7 +25,7 @@ hostprogs-y := fw_printenv
lib-y += fw_env.o \
crc32.o ctype.o linux_string.o \
env_attr.o env_flags.o aes.o
env_attr.o env_flags.o
fw_printenv-objs := fw_env_main.o $(lib-y)

1
tools/env/aes.c vendored
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@ -1 +0,0 @@
#include "../../lib/aes.c"

79
tools/env/fw_env.c vendored
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@ -111,8 +111,6 @@ static struct environment environment = {
.flag_scheme = FLAG_NONE,
};
static int env_aes_cbc_crypt(char *data, const int enc, uint8_t *key);
static int HaveRedundEnv = 0;
static unsigned char active_flag = 1;
@ -217,34 +215,6 @@ char *fw_getdefenv(char *name)
return NULL;
}
int parse_aes_key(char *key, uint8_t *bin_key)
{
char tmp[5] = { '0', 'x', 0, 0, 0 };
unsigned long ul;
int i;
if (strnlen(key, 64) != 32) {
fprintf(stderr,
"## Error: '-a' option requires 16-byte AES key\n");
return -1;
}
for (i = 0; i < 16; i++) {
tmp[2] = key[0];
tmp[3] = key[1];
errno = 0;
ul = strtoul(tmp, NULL, 16);
if (errno) {
fprintf(stderr,
"## Error: '-a' option requires valid AES key\n");
return -1;
}
bin_key[i] = ul & 0xff;
key += 2;
}
return 0;
}
/*
* Print the current definition of one, or more, or all
* environment variables
@ -313,16 +283,6 @@ int fw_env_flush(struct env_opts *opts)
if (!opts)
opts = &default_opts;
if (opts->aes_flag) {
ret = env_aes_cbc_crypt(environment.data, 1,
opts->aes_key);
if (ret) {
fprintf(stderr,
"Error: can't encrypt env for flash\n");
return ret;
}
}
/*
* Update CRC
*/
@ -976,28 +936,6 @@ static int flash_flag_obsolete (int dev, int fd, off_t offset)
return rc;
}
/* Encrypt or decrypt the environment before writing or reading it. */
static int env_aes_cbc_crypt(char *payload, const int enc, uint8_t *key)
{
uint8_t *data = (uint8_t *)payload;
const int len = usable_envsize;
uint8_t key_exp[AES_EXPAND_KEY_LENGTH];
uint32_t aes_blocks;
/* First we expand the key. */
aes_expand_key(key, key_exp);
/* Calculate the number of AES blocks to encrypt. */
aes_blocks = DIV_ROUND_UP(len, AES_KEY_LENGTH);
if (enc)
aes_cbc_encrypt_blocks(key_exp, data, data, aes_blocks);
else
aes_cbc_decrypt_blocks(key_exp, data, data, aes_blocks);
return 0;
}
static int flash_write (int fd_current, int fd_target, int dev_target)
{
int rc;
@ -1182,13 +1120,6 @@ int fw_env_open(struct env_opts *opts)
crc0 = crc32 (0, (uint8_t *) environment.data, ENV_SIZE);
if (opts->aes_flag) {
ret = env_aes_cbc_crypt(environment.data, 0,
opts->aes_key);
if (ret)
goto open_cleanup;
}
crc0_ok = (crc0 == *environment.crc);
if (!HaveRedundEnv) {
if (!crc0_ok) {
@ -1244,13 +1175,6 @@ int fw_env_open(struct env_opts *opts)
crc1 = crc32 (0, (uint8_t *) redundant->data, ENV_SIZE);
if (opts->aes_flag) {
ret = env_aes_cbc_crypt(redundant->data, 0,
opts->aes_key);
if (ret)
goto open_cleanup;
}
crc1_ok = (crc1 == redundant->crc);
flag1 = redundant->flags;
@ -1498,9 +1422,6 @@ static int parse_config(struct env_opts *opts)
if (HaveRedundEnv)
usable_envsize -= sizeof(char);
if (opts->aes_flag)
usable_envsize &= ~(AES_KEY_LENGTH - 1);
return 0;
}

5
tools/env/fw_env.h vendored
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@ -6,7 +6,6 @@
*/
#include <stdint.h>
#include <uboot_aes.h>
/*
* Programs using the library must check which API is available,
@ -19,13 +18,9 @@ struct env_opts {
#ifdef CONFIG_FILE
char *config_file;
#endif
int aes_flag; /* Is AES encryption used? */
uint8_t aes_key[AES_KEY_LENGTH];
char *lockname;
};
int parse_aes_key(char *key, uint8_t *bin_key);
/**
* fw_printenv() - print one or several environment variables
*

View File

@ -43,7 +43,6 @@
static int do_printenv;
static struct option long_options[] = {
{"aes", required_argument, NULL, 'a'},
{"config", required_argument, NULL, 'c'},
{"help", no_argument, NULL, 'h'},
{"script", required_argument, NULL, 's'},
@ -70,9 +69,6 @@ void usage_printenv(void)
"\n"
" -h, --help print this help.\n"
" -v, --version display version\n"
#ifdef CONFIG_ENV_AES
" -a, --aes aes key to access environment\n"
#endif
#ifdef CONFIG_FILE
" -c, --config configuration file, default:" CONFIG_FILE "\n"
#endif
@ -89,9 +85,6 @@ void usage_env_set(void)
"\n"
" -h, --help print this help.\n"
" -v, --version display version\n"
#ifdef CONFIG_ENV_AES
" -a, --aes aes key to access environment\n"
#endif
#ifdef CONFIG_FILE
" -c, --config configuration file, default:" CONFIG_FILE "\n"
#endif
@ -130,13 +123,6 @@ static void parse_common_args(int argc, char *argv[])
while ((c = getopt_long(argc, argv, ":a:c:l:h:v", long_options, NULL)) !=
EOF) {
switch (c) {
case 'a':
if (parse_aes_key(optarg, env_opts.aes_key)) {
fprintf(stderr, "AES key parse error\n");
exit(EXIT_FAILURE);
}
env_opts.aes_flag = 1;
break;
#ifdef CONFIG_FILE
case 'c':
env_opts.config_file = optarg;