[people/ms/u-boot.git] / env / common.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,
};

/*
 * Read an environment variable as a boolean
 * Return -1 if variable does not exist (default to true)
 */
int env_get_yesno(const char *var)
{
	char *s = env_get(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 = env_get(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;
	gd->flags |= GD_FLG_ENV_DEFAULT;
}


/* [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 <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.
 */
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;
}

#ifdef CONFIG_SYS_REDUNDAND_ENVIRONMENT
static unsigned char env_flags;

int env_import_redund(const char *buf1, const char *buf2)
{
	int crc1_ok, crc2_ok;
	env_t *ep, *tmp_env1, *tmp_env2;

	tmp_env1 = (env_t *)buf1;
	tmp_env2 = (env_t *)buf2;

	crc1_ok = crc32(0, tmp_env1->data, ENV_SIZE) ==
			tmp_env1->crc;
	crc2_ok = crc32(0, tmp_env2->data, ENV_SIZE) ==
			tmp_env2->crc;

	if (!crc1_ok && !crc2_ok) {
		set_default_env("!bad CRC");
		return 0;
	} else if (crc1_ok && !crc2_ok) {
		gd->env_valid = 1;
	} else if (!crc1_ok && crc2_ok) {
		gd->env_valid = 2;
	} else {
		/* both ok - check serial */
		if (tmp_env1->flags == 255 && tmp_env2->flags == 0)
			gd->env_valid = 2;
		else if (tmp_env2->flags == 255 && tmp_env1->flags == 0)
			gd->env_valid = 1;
		else if (tmp_env1->flags > tmp_env2->flags)
			gd->env_valid = 1;
		else if (tmp_env2->flags > tmp_env1->flags)
			gd->env_valid = 2;
		else /* flags are equal - almost impossible */
			gd->env_valid = 1;
	}

	if (gd->env_valid == 1)
		ep = tmp_env1;
	else
		ep = tmp_env2;

	env_flags = ep->flags;
	return env_import((char *)ep, 0);
}
#endif /* CONFIG_SYS_REDUNDAND_ENVIRONMENT */

/* Export 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);

#ifdef CONFIG_SYS_REDUNDAND_ENVIRONMENT
	env_out->flags = ++env_flags; /* increase the serial */
#endif

	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_load();
	}
}

#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
Commit	Line	Data
05706fdd	1	/*
ea882baf	2	* (C) Copyright 2000-2010
05706fdd WD	3	* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
	4	*
	5	* (C) Copyright 2001 Sysgo Real-Time Solutions, GmbH <www.elinos.com>
	6	* Andreas Heppel <aheppel@sysgo.de>
ea882baf	7	*
3765b3e7	8	* SPDX-License-Identifier: GPL-2.0+
05706fdd WD	9	*/
	10
	11	#include <common.h>
	12	#include <command.h>
	13	#include <environment.h>
05706fdd	14	#include <linux/stddef.h>
ea882baf WD	15	#include <search.h>
ea882baf WD	16	#include <errno.h>
05706fdd WD	17	#include <malloc.h>
05706fdd WD	18
d87080b7 WD	19	DECLARE_GLOBAL_DATA_PTR;
d87080b7 WD	20
05706fdd WD	21	/************************************************************************
	22	* Default settings to be used when no valid environment is found
	23	*/
ddd8418f	24	#include <env_default.h>
05706fdd	25
c5983592	26	struct hsearch_data env_htab = {
2598090b	27	.change_ok = env_flags_validate,
c5983592	28	};
2eb1573f	29
ec8a252c JH	30	/*
	31	* Read an environment variable as a boolean
	32	* Return -1 if variable does not exist (default to true)
	33	*/
bfebc8c9	34	int env_get_yesno(const char *var)
ec8a252c	35	{
00caae6d	36	char *s = env_get(var);
ec8a252c JH	37
	38	if (s == NULL)
	39	return -1;
	40	return (s == '1' \|\| s == 'y' \|\| s == 'Y' \|\| s == 't' \|\| *s == 'T') ?
	41	1 : 0;
	42	}
	43
267541f7 JH	44	/*
	45	* Look up the variable from the default environment
	46	*/
	47	char getenv_default(const char name)
	48	{
	49	char *ret_val;
	50	unsigned long really_valid = gd->env_valid;
	51	unsigned long real_gd_flags = gd->flags;
	52
	53	/* Pretend that the image is bad. */
	54	gd->flags &= ~GD_FLG_ENV_READY;
	55	gd->env_valid = 0;
00caae6d	56	ret_val = env_get(name);
267541f7 JH	57	gd->env_valid = really_valid;
	58	gd->flags = real_gd_flags;
	59	return ret_val;
	60	}
	61
ea882baf	62	void set_default_env(const char *s)
5bb12dbd	63	{
c4e0057f JH	64	int flags = 0;
c4e0057f JH	65
5bb12dbd	66	if (sizeof(default_environment) > ENV_SIZE) {
ea882baf	67	puts("*** Error - default environment is too large\n\n");
5bb12dbd HW	68	return;
	69	}
	70
ea882baf WD	71	if (s) {
	72	if (*s == '!') {
	73	printf("*** Warning - %s, "
	74	"using default environment\n\n",
27aafe98	75	s + 1);
ea882baf	76	} else {
c4e0057f	77	flags = H_INTERACTIVE;
ea882baf WD	78	puts(s);
	79	}
	80	} else {
	81	puts("Using default environment\n\n");
	82	}
	83
2eb1573f	84	if (himport_r(&env_htab, (char *)default_environment,
ecd1446f	85	sizeof(default_environment), '\0', flags, 0,
c4e0057f	86	0, NULL) == 0)
ea882baf	87	error("Environment import failed: errno = %d\n", errno);
27aafe98	88
ea882baf	89	gd->flags \|= GD_FLG_ENV_READY;
340b0e3b	90	gd->flags \|= GD_FLG_ENV_DEFAULT;
5bb12dbd HW	91	}
5bb12dbd HW	92
b64b7c3d GF	93
	94	/* [re]set individual variables to their value in the default environment */
	95	int set_default_vars(int nvars, char * const vars[])
	96	{
	97	/*
	98	* Special use-case: import from default environment
	99	* (and use \0 as a separator)
	100	*/
	101	return himport_r(&env_htab, (const char *)default_environment,
c4e0057f	102	sizeof(default_environment), '\0',
ecd1446f	103	H_NOCLEAR \| H_INTERACTIVE, 0, nvars, vars);
b64b7c3d GF	104	}
b64b7c3d GF	105
a4223b74	106	#ifdef CONFIG_ENV_AES
b80c0b99	107	#include <uboot_aes.h>
a4223b74 MV	108	/**
	109	* env_aes_cbc_get_key() - Get AES-128-CBC key for the environment
	110	*
	111	* This function shall return 16-byte array containing AES-128 key used
62a3b7dd	112	* to encrypt and decrypt the environment. This function must be overridden
a4223b74 MV	113	* by the implementer as otherwise the environment encryption will not
	114	* work.
	115	*/
	116	__weak uint8_t *env_aes_cbc_get_key(void)
	117	{
	118	return NULL;
	119	}
	120
	121	static int env_aes_cbc_crypt(env_t *env, const int enc)
	122	{
	123	unsigned char *data = env->data;
	124	uint8_t *key;
	125	uint8_t key_exp[AES_EXPAND_KEY_LENGTH];
	126	uint32_t aes_blocks;
	127
	128	key = env_aes_cbc_get_key();
	129	if (!key)
	130	return -EINVAL;
	131
	132	/* First we expand the key. */
	133	aes_expand_key(key, key_exp);
	134
	135	/* Calculate the number of AES blocks to encrypt. */
	136	aes_blocks = ENV_SIZE / AES_KEY_LENGTH;
	137
	138	if (enc)
	139	aes_cbc_encrypt_blocks(key_exp, data, data, aes_blocks);
	140	else
	141	aes_cbc_decrypt_blocks(key_exp, data, data, aes_blocks);
	142
	143	return 0;
	144	}
	145	#else
	146	static inline int env_aes_cbc_crypt(env_t *env, const int enc)
	147	{
	148	return 0;
	149	}
	150	#endif
	151
ea882baf WD	152	/*
	153	* Check if CRC is valid and (if yes) import the environment.
	154	* Note that "buf" may or may not be aligned.
	155	*/
	156	int env_import(const char *buf, int check)
05706fdd	157	{
ea882baf	158	env_t ep = (env_t )buf;
a4223b74	159	int ret;
05706fdd	160
ea882baf WD	161	if (check) {
	162	uint32_t crc;
	163
	164	memcpy(&crc, &ep->crc, sizeof(crc));
	165
	166	if (crc32(0, ep->data, ENV_SIZE) != crc) {
	167	set_default_env("!bad CRC");
	168	return 0;
	169	}
	170	}
	171
a4223b74 MV	172	/* Decrypt the env if desired. */
	173	ret = env_aes_cbc_crypt(ep, 0);
	174	if (ret) {
	175	error("Failed to decrypt env!\n");
	176	set_default_env("!import failed");
	177	return ret;
	178	}
	179
ecd1446f	180	if (himport_r(&env_htab, (char *)ep->data, ENV_SIZE, '\0', 0, 0,
c4e0057f	181	0, NULL)) {
ea882baf WD	182	gd->flags \|= GD_FLG_ENV_READY;
	183	return 1;
	184	}
05706fdd	185
ea882baf WD	186	error("Cannot import environment: errno = %d\n", errno);
	187
	188	set_default_env("!import failed");
	189
	190	return 0;
	191	}
	192
76768f5f FA	193	#ifdef CONFIG_SYS_REDUNDAND_ENVIRONMENT
	194	static unsigned char env_flags;
	195
	196	int env_import_redund(const char buf1, const char buf2)
	197	{
	198	int crc1_ok, crc2_ok;
	199	env_t ep, tmp_env1, *tmp_env2;
	200
	201	tmp_env1 = (env_t *)buf1;
	202	tmp_env2 = (env_t *)buf2;
	203
	204	crc1_ok = crc32(0, tmp_env1->data, ENV_SIZE) ==
	205	tmp_env1->crc;
	206	crc2_ok = crc32(0, tmp_env2->data, ENV_SIZE) ==
	207	tmp_env2->crc;
	208
	209	if (!crc1_ok && !crc2_ok) {
	210	set_default_env("!bad CRC");
	211	return 0;
	212	} else if (crc1_ok && !crc2_ok) {
	213	gd->env_valid = 1;
	214	} else if (!crc1_ok && crc2_ok) {
	215	gd->env_valid = 2;
	216	} else {
	217	/* both ok - check serial */
	218	if (tmp_env1->flags == 255 && tmp_env2->flags == 0)
	219	gd->env_valid = 2;
	220	else if (tmp_env2->flags == 255 && tmp_env1->flags == 0)
	221	gd->env_valid = 1;
	222	else if (tmp_env1->flags > tmp_env2->flags)
	223	gd->env_valid = 1;
	224	else if (tmp_env2->flags > tmp_env1->flags)
	225	gd->env_valid = 2;
	226	else /* flags are equal - almost impossible */
	227	gd->env_valid = 1;
	228	}
	229
	230	if (gd->env_valid == 1)
	231	ep = tmp_env1;
	232	else
	233	ep = tmp_env2;
	234
	235	env_flags = ep->flags;
	236	return env_import((char *)ep, 0);
	237	}
	238	#endif /* CONFIG_SYS_REDUNDAND_ENVIRONMENT */
	239
fc0b5948	240	/* Export the environment and generate CRC for it. */
7ce1526e MV	241	int env_export(env_t *env_out)
	242	{
	243	char *res;
	244	ssize_t len;
a4223b74	245	int ret;
7ce1526e MV	246
	247	res = (char *)env_out->data;
	248	len = hexport_r(&env_htab, '\0', 0, &res, ENV_SIZE, 0, NULL);
	249	if (len < 0) {
	250	error("Cannot export environment: errno = %d\n", errno);
	251	return 1;
	252	}
a4223b74 MV	253
	254	/* Encrypt the env if desired. */
	255	ret = env_aes_cbc_crypt(env_out, 1);
	256	if (ret)
	257	return ret;
	258
7ce1526e MV	259	env_out->crc = crc32(0, env_out->data, ENV_SIZE);
7ce1526e MV	260
76768f5f FA	261	#ifdef CONFIG_SYS_REDUNDAND_ENVIRONMENT
	262	env_out->flags = ++env_flags; /* increase the serial */
	263	#endif
	264
7ce1526e MV	265	return 0;
	266	}
	267
27aafe98	268	void env_relocate(void)
ea882baf	269	{
2e5167cc	270	#if defined(CONFIG_NEEDS_MANUAL_RELOC)
60f7da1f	271	env_reloc();
7afcf3a5	272	env_htab.change_ok += gd->reloc_off;
60f7da1f	273	#endif
05706fdd	274	if (gd->env_valid == 0) {
7ac2fe2d IY	275	#if defined(CONFIG_ENV_IS_NOWHERE) \|\| defined(CONFIG_SPL_BUILD)
7ac2fe2d IY	276	/* Environment not changable */
ea882baf	277	set_default_env(NULL);
05706fdd	278	#else
770605e4	279	bootstage_error(BOOTSTAGE_ID_NET_CHECKSUM);
ea882baf	280	set_default_env("!bad CRC");
d259079d	281	#endif
ea882baf	282	} else {
310fb14b	283	env_load();
05706fdd	284	}
05706fdd	285	}
04a85b3b	286
7ac2fe2d	287	#if defined(CONFIG_AUTO_COMPLETE) && !defined(CONFIG_SPL_BUILD)
04a85b3b WD	288	int env_complete(char var, int maxv, char cmdv[], int bufsz, char *buf)
04a85b3b WD	289	{
560d424b MF	290	ENTRY *match;
560d424b MF	291	int found, idx;
04a85b3b	292
560d424b	293	idx = 0;
04a85b3b WD	294	found = 0;
	295	cmdv[0] = NULL;
	296
560d424b MF	297	while ((idx = hmatch_r(var, idx, &match, &env_htab))) {
560d424b MF	298	int vallen = strlen(match->key) + 1;
04a85b3b	299
560d424b	300	if (found >= maxv - 2 \|\| bufsz < vallen)
04a85b3b	301	break;
560d424b	302
04a85b3b	303	cmdv[found++] = buf;
560d424b MF	304	memcpy(buf, match->key, vallen);
	305	buf += vallen;
	306	bufsz -= vallen;
04a85b3b WD	307	}
04a85b3b WD	308
560d424b MF	309	qsort(cmdv, found, sizeof(cmdv[0]), strcmp_compar);
	310
	311	if (idx)
	312	cmdv[found++] = "...";
27aafe98	313
04a85b3b WD	314	cmdv[found] = NULL;
	315	return found;
	316	}
	317	#endif