u-boot/common/env_common.c
Alexander Holler ecd1446fe1 Add option -r to env import to allow import of text files with CRLF as line endings
When this option is enabled, CRLF is treated like LF when importing environments
from text files, which means CRs ('\r') in front of LFs ('\n') are just ignored.

Drawback of enabling this option is that (maybe exported) variables which have
a trailing CR in their content will get imported without that CR. But this
drawback is very unlikely and the big advantage of letting Windows user create
a *working* uEnv.txt too is likely more welcome.

Signed-off-by: Alexander Holler <holler@ahsoftware.de>
2014-07-22 07:44:26 -04:00

301 lines
6.2 KiB
C

/*
* (C) Copyright 2000-2010
* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
*
* (C) Copyright 2001 Sysgo Real-Time Solutions, GmbH <www.elinos.com>
* Andreas Heppel <aheppel@sysgo.de>
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <command.h>
#include <environment.h>
#include <linux/stddef.h>
#include <search.h>
#include <errno.h>
#include <malloc.h>
DECLARE_GLOBAL_DATA_PTR;
/************************************************************************
* Default settings to be used when no valid environment is found
*/
#include <env_default.h>
struct hsearch_data env_htab = {
.change_ok = env_flags_validate,
};
__weak uchar env_get_char_spec(int index)
{
return *((uchar *)(gd->env_addr + index));
}
static uchar env_get_char_init(int index)
{
/* if crc was bad, use the default environment */
if (gd->env_valid)
return env_get_char_spec(index);
else
return default_environment[index];
}
uchar env_get_char_memory(int index)
{
return *env_get_addr(index);
}
uchar env_get_char(int index)
{
/* if relocated to RAM */
if (gd->flags & GD_FLG_RELOC)
return env_get_char_memory(index);
else
return env_get_char_init(index);
}
const uchar *env_get_addr(int index)
{
if (gd->env_valid)
return (uchar *)(gd->env_addr + index);
else
return &default_environment[index];
}
/*
* Read an environment variable as a boolean
* Return -1 if variable does not exist (default to true)
*/
int getenv_yesno(const char *var)
{
char *s = getenv(var);
if (s == NULL)
return -1;
return (*s == '1' || *s == 'y' || *s == 'Y' || *s == 't' || *s == 'T') ?
1 : 0;
}
/*
* Look up the variable from the default environment
*/
char *getenv_default(const char *name)
{
char *ret_val;
unsigned long really_valid = gd->env_valid;
unsigned long real_gd_flags = gd->flags;
/* Pretend that the image is bad. */
gd->flags &= ~GD_FLG_ENV_READY;
gd->env_valid = 0;
ret_val = getenv(name);
gd->env_valid = really_valid;
gd->flags = real_gd_flags;
return ret_val;
}
void set_default_env(const char *s)
{
int flags = 0;
if (sizeof(default_environment) > ENV_SIZE) {
puts("*** Error - default environment is too large\n\n");
return;
}
if (s) {
if (*s == '!') {
printf("*** Warning - %s, "
"using default environment\n\n",
s + 1);
} else {
flags = H_INTERACTIVE;
puts(s);
}
} else {
puts("Using default environment\n\n");
}
if (himport_r(&env_htab, (char *)default_environment,
sizeof(default_environment), '\0', flags, 0,
0, NULL) == 0)
error("Environment import failed: errno = %d\n", errno);
gd->flags |= GD_FLG_ENV_READY;
}
/* [re]set individual variables to their value in the default environment */
int set_default_vars(int nvars, char * const vars[])
{
/*
* Special use-case: import from default environment
* (and use \0 as a separator)
*/
return himport_r(&env_htab, (const char *)default_environment,
sizeof(default_environment), '\0',
H_NOCLEAR | H_INTERACTIVE, 0, nvars, vars);
}
#ifdef CONFIG_ENV_AES
#include <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 overriden
* 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.
*/
int env_import(const char *buf, int check)
{
env_t *ep = (env_t *)buf;
int ret;
if (check) {
uint32_t crc;
memcpy(&crc, &ep->crc, sizeof(crc));
if (crc32(0, ep->data, ENV_SIZE) != crc) {
set_default_env("!bad CRC");
return 0;
}
}
/* Decrypt the env if desired. */
ret = env_aes_cbc_crypt(ep, 0);
if (ret) {
error("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;
return 1;
}
error("Cannot import environment: errno = %d\n", errno);
set_default_env("!import failed");
return 0;
}
/* Emport the environment and generate CRC for it. */
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);
if (len < 0) {
error("Cannot export environment: errno = %d\n", errno);
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);
return 0;
}
void env_relocate(void)
{
#if defined(CONFIG_NEEDS_MANUAL_RELOC)
env_reloc();
env_htab.change_ok += gd->reloc_off;
#endif
if (gd->env_valid == 0) {
#if defined(CONFIG_ENV_IS_NOWHERE) || defined(CONFIG_SPL_BUILD)
/* Environment not changable */
set_default_env(NULL);
#else
bootstage_error(BOOTSTAGE_ID_NET_CHECKSUM);
set_default_env("!bad CRC");
#endif
} else {
env_relocate_spec();
}
}
#if defined(CONFIG_AUTO_COMPLETE) && !defined(CONFIG_SPL_BUILD)
int env_complete(char *var, int maxv, char *cmdv[], int bufsz, char *buf)
{
ENTRY *match;
int found, idx;
idx = 0;
found = 0;
cmdv[0] = NULL;
while ((idx = hmatch_r(var, idx, &match, &env_htab))) {
int vallen = strlen(match->key) + 1;
if (found >= maxv - 2 || bufsz < vallen)
break;
cmdv[found++] = buf;
memcpy(buf, match->key, vallen);
buf += vallen;
bufsz -= vallen;
}
qsort(cmdv, found, sizeof(cmdv[0]), strcmp_compar);
if (idx)
cmdv[found++] = "...";
cmdv[found] = NULL;
return found;
}
#endif