[u-boot.git] / common / env_flags.c

/*
 * (C) Copyright 2012
 * Joe Hershberger, National Instruments, [email protected]
 *
 * SPDX-License-Identifier:	GPL-2.0+
 */

#include <linux/string.h>
#include <linux/ctype.h>

#ifdef USE_HOSTCC /* Eliminate "ANSI does not permit..." warnings */
#include <stdint.h>
#include <stdio.h>
#include "fw_env.h"
#include <env_attr.h>
#include <env_flags.h>
#define getenv fw_getenv
#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
#else
#include <common.h>
#include <environment.h>
#endif

#ifdef CONFIG_CMD_NET
#define ENV_FLAGS_NET_VARTYPE_REPS "im"
#else
#define ENV_FLAGS_NET_VARTYPE_REPS ""
#endif

static const char env_flags_vartype_rep[] = "sdxb" ENV_FLAGS_NET_VARTYPE_REPS;
static const char env_flags_varaccess_rep[] = "aroc";
static const int env_flags_varaccess_mask[] = {
	0,
	ENV_FLAGS_VARACCESS_PREVENT_DELETE |
		ENV_FLAGS_VARACCESS_PREVENT_CREATE |
		ENV_FLAGS_VARACCESS_PREVENT_OVERWR,
	ENV_FLAGS_VARACCESS_PREVENT_DELETE |
		ENV_FLAGS_VARACCESS_PREVENT_OVERWR,
	ENV_FLAGS_VARACCESS_PREVENT_DELETE |
		ENV_FLAGS_VARACCESS_PREVENT_NONDEF_OVERWR};

#ifdef CONFIG_CMD_ENV_FLAGS
static const char * const env_flags_vartype_names[] = {
	"string",
	"decimal",
	"hexadecimal",
	"boolean",
#ifdef CONFIG_CMD_NET
	"IP address",
	"MAC address",
#endif
};
static const char * const env_flags_varaccess_names[] = {
	"any",
	"read-only",
	"write-once",
	"change-default",
};

/*
 * Print the whole list of available type flags.
 */
void env_flags_print_vartypes(void)
{
	enum env_flags_vartype curtype = (enum env_flags_vartype)0;

	while (curtype != env_flags_vartype_end) {
		printf("\t%c   -\t%s\n", env_flags_vartype_rep[curtype],
			env_flags_vartype_names[curtype]);
		curtype++;
	}
}

/*
 * Print the whole list of available access flags.
 */
void env_flags_print_varaccess(void)
{
	enum env_flags_varaccess curaccess = (enum env_flags_varaccess)0;

	while (curaccess != env_flags_varaccess_end) {
		printf("\t%c   -\t%s\n", env_flags_varaccess_rep[curaccess],
			env_flags_varaccess_names[curaccess]);
		curaccess++;
	}
}

/*
 * Return the name of the type.
 */
const char *env_flags_get_vartype_name(enum env_flags_vartype type)
{
	return env_flags_vartype_names[type];
}

/*
 * Return the name of the access.
 */
const char *env_flags_get_varaccess_name(enum env_flags_varaccess access)
{
	return env_flags_varaccess_names[access];
}
#endif /* CONFIG_CMD_ENV_FLAGS */

/*
 * Parse the flags string from a .flags attribute list into the vartype enum.
 */
enum env_flags_vartype env_flags_parse_vartype(const char *flags)
{
	char *type;

	if (strlen(flags) <= ENV_FLAGS_VARTYPE_LOC)
		return env_flags_vartype_string;

	type = strchr(env_flags_vartype_rep,
		flags[ENV_FLAGS_VARTYPE_LOC]);

	if (type != NULL)
		return (enum env_flags_vartype)
			(type - &env_flags_vartype_rep[0]);

	printf("## Warning: Unknown environment variable type '%c'\n",
		flags[ENV_FLAGS_VARTYPE_LOC]);
	return env_flags_vartype_string;
}

/*
 * Parse the flags string from a .flags attribute list into the varaccess enum.
 */
enum env_flags_varaccess env_flags_parse_varaccess(const char *flags)
{
	char *access;

	if (strlen(flags) <= ENV_FLAGS_VARACCESS_LOC)
		return env_flags_varaccess_any;

	access = strchr(env_flags_varaccess_rep,
		flags[ENV_FLAGS_VARACCESS_LOC]);

	if (access != NULL)
		return (enum env_flags_varaccess)
			(access - &env_flags_varaccess_rep[0]);

	printf("## Warning: Unknown environment variable access method '%c'\n",
		flags[ENV_FLAGS_VARACCESS_LOC]);
	return env_flags_varaccess_any;
}

/*
 * Parse the binary flags from a hash table entry into the varaccess enum.
 */
enum env_flags_varaccess env_flags_parse_varaccess_from_binflags(int binflags)
{
	int i;

	for (i = 0; i < ARRAY_SIZE(env_flags_varaccess_mask); i++)
		if (env_flags_varaccess_mask[i] ==
		    (binflags & ENV_FLAGS_VARACCESS_BIN_MASK))
			return (enum env_flags_varaccess)i;

	printf("Warning: Non-standard access flags. (0x%x)\n",
		binflags & ENV_FLAGS_VARACCESS_BIN_MASK);

	return env_flags_varaccess_any;
}

static inline int is_hex_prefix(const char *value)
{
	return value[0] == '0' && (value[1] == 'x' || value[1] == 'X');
}

static void skip_num(int hex, const char *value, const char **end,
	int max_digits)
{
	int i;

	if (hex && is_hex_prefix(value))
		value += 2;

	for (i = max_digits; i != 0; i--) {
		if (hex && !isxdigit(*value))
			break;
		if (!hex && !isdigit(*value))
			break;
		value++;
	}
	if (end != NULL)
		*end = value;
}

#ifdef CONFIG_CMD_NET
int eth_validate_ethaddr_str(const char *addr)
{
	const char *end;
	const char *cur;
	int i;

	cur = addr;
	for (i = 0; i < 6; i++) {
		skip_num(1, cur, &end, 2);
		if (cur == end)
			return -1;
		if (cur + 2 == end && is_hex_prefix(cur))
			return -1;
		if (i != 5 && *end != ':')
			return -1;
		if (i == 5 && *end != '\0')
			return -1;
		cur = end + 1;
	}

	return 0;
}
#endif

/*
 * Based on the declared type enum, validate that the value string complies
 * with that format
 */
static int _env_flags_validate_type(const char *value,
	enum env_flags_vartype type)
{
	const char *end;
#ifdef CONFIG_CMD_NET
	const char *cur;
	int i;
#endif

	switch (type) {
	case env_flags_vartype_string:
		break;
	case env_flags_vartype_decimal:
		skip_num(0, value, &end, -1);
		if (*end != '\0')
			return -1;
		break;
	case env_flags_vartype_hex:
		skip_num(1, value, &end, -1);
		if (*end != '\0')
			return -1;
		if (value + 2 == end && is_hex_prefix(value))
			return -1;
		break;
	case env_flags_vartype_bool:
		if (value[0] != '1' && value[0] != 'y' && value[0] != 't' &&
		    value[0] != 'Y' && value[0] != 'T' &&
		    value[0] != '0' && value[0] != 'n' && value[0] != 'f' &&
		    value[0] != 'N' && value[0] != 'F')
			return -1;
		if (value[1] != '\0')
			return -1;
		break;
#ifdef CONFIG_CMD_NET
	case env_flags_vartype_ipaddr:
		cur = value;
		for (i = 0; i < 4; i++) {
			skip_num(0, cur, &end, 3);
			if (cur == end)
				return -1;
			if (i != 3 && *end != '.')
				return -1;
			if (i == 3 && *end != '\0')
				return -1;
			cur = end + 1;
		}
		break;
	case env_flags_vartype_macaddr:
		if (eth_validate_ethaddr_str(value))
			return -1;
		break;
#endif
	case env_flags_vartype_end:
		return -1;
	}

	/* OK */
	return 0;
}

/*
 * Look for flags in a provided list and failing that the static list
 */
static inline int env_flags_lookup(const char *flags_list, const char *name,
	char *flags)
{
	int ret = 1;

	if (!flags)
		/* bad parameter */
		return -1;

	/* try the env first */
	if (flags_list)
		ret = env_attr_lookup(flags_list, name, flags);

	if (ret != 0)
		/* if not found in the env, look in the static list */
		ret = env_attr_lookup(ENV_FLAGS_LIST_STATIC, name, flags);

	return ret;
}

#ifdef USE_HOSTCC /* Functions only used from tools/env */
/*
 * Look up any flags directly from the .flags variable and the static list
 * and convert them to the vartype enum.
 */
enum env_flags_vartype env_flags_get_type(const char *name)
{
	const char *flags_list = getenv(ENV_FLAGS_VAR);
	char flags[ENV_FLAGS_ATTR_MAX_LEN + 1];

	if (env_flags_lookup(flags_list, name, flags))
		return env_flags_vartype_string;

	if (strlen(flags) <= ENV_FLAGS_VARTYPE_LOC)
		return env_flags_vartype_string;

	return env_flags_parse_vartype(flags);
}

/*
 * Look up the access of a variable directly from the .flags var.
 */
enum env_flags_varaccess env_flags_get_varaccess(const char *name)
{
	const char *flags_list = getenv(ENV_FLAGS_VAR);
	char flags[ENV_FLAGS_ATTR_MAX_LEN + 1];

	if (env_flags_lookup(flags_list, name, flags))
		return env_flags_varaccess_any;

	if (strlen(flags) <= ENV_FLAGS_VARACCESS_LOC)
		return env_flags_varaccess_any;

	return env_flags_parse_varaccess(flags);
}

/*
 * Validate that the proposed new value for "name" is valid according to the
 * defined flags for that variable, if any.
 */
int env_flags_validate_type(const char *name, const char *value)
{
	enum env_flags_vartype type;

	if (value == NULL)
		return 0;
	type = env_flags_get_type(name);
	if (_env_flags_validate_type(value, type) < 0) {
		printf("## Error: flags type check failure for "
			"\"%s\" <= \"%s\" (type: %c)\n",
			name, value, env_flags_vartype_rep[type]);
		return -1;
	}
	return 0;
}

/*
 * Validate that the proposed access to variable "name" is valid according to
 * the defined flags for that variable, if any.
 */
int env_flags_validate_varaccess(const char *name, int check_mask)
{
	enum env_flags_varaccess access;
	int access_mask;

	access = env_flags_get_varaccess(name);
	access_mask = env_flags_varaccess_mask[access];

	return (check_mask & access_mask) != 0;
}

/*
 * Validate the parameters to "env set" directly
 */
int env_flags_validate_env_set_params(char *name, char * const val[], int count)
{
	if ((count >= 1) && val[0] != NULL) {
		enum env_flags_vartype type = env_flags_get_type(name);

		/*
		 * we don't currently check types that need more than
		 * one argument
		 */
		if (type != env_flags_vartype_string && count > 1) {
			printf("## Error: too many parameters for setting \"%s\"\n",
			       name);
			return -1;
		}
		return env_flags_validate_type(name, val[0]);
	}
	/* ok */
	return 0;
}

#else /* !USE_HOSTCC - Functions only used from lib/hashtable.c */

/*
 * Parse the flag charachters from the .flags attribute list into the binary
 * form to be stored in the environment entry->flags field.
 */
static int env_parse_flags_to_bin(const char *flags)
{
	int binflags;

	binflags = env_flags_parse_vartype(flags) & ENV_FLAGS_VARTYPE_BIN_MASK;
	binflags |= env_flags_varaccess_mask[env_flags_parse_varaccess(flags)];

	return binflags;
}

static int first_call = 1;
static const char *flags_list;

/*
 * Look for possible flags for a newly added variable
 * This is called specifically when the variable did not exist in the hash
 * previously, so the blanket update did not find this variable.
 */
void env_flags_init(ENTRY *var_entry)
{
	const char *var_name = var_entry->key;
	char flags[ENV_FLAGS_ATTR_MAX_LEN + 1] = "";
	int ret = 1;

	if (first_call) {
		flags_list = getenv(ENV_FLAGS_VAR);
		first_call = 0;
	}
	/* look in the ".flags" and static for a reference to this variable */
	ret = env_flags_lookup(flags_list, var_name, flags);

	/* if any flags were found, set the binary form to the entry */
	if (!ret && strlen(flags))
		var_entry->flags = env_parse_flags_to_bin(flags);
}

/*
 * Called on each existing env var prior to the blanket update since removing
 * a flag in the flag list should remove its flags.
 */
static int clear_flags(ENTRY *entry)
{
	entry->flags = 0;

	return 0;
}

/*
 * Call for each element in the list that defines flags for a variable
 */
static int set_flags(const char *name, const char *value, void *priv)
{
	ENTRY e, *ep;

	e.key	= name;
	e.data	= NULL;
	e.callback = NULL;
	hsearch_r(e, FIND, &ep, &env_htab, 0);

	/* does the env variable actually exist? */
	if (ep != NULL) {
		/* the flag list is empty, so clear the flags */
		if (value == NULL || strlen(value) == 0)
			ep->flags = 0;
		else
			/* assign the requested flags */
			ep->flags = env_parse_flags_to_bin(value);
	}

	return 0;
}

static int on_flags(const char *name, const char *value, enum env_op op,
	int flags)
{
	/* remove all flags */
	hwalk_r(&env_htab, clear_flags);

	/* configure any static flags */
	env_attr_walk(ENV_FLAGS_LIST_STATIC, set_flags, NULL);
	/* configure any dynamic flags */
	env_attr_walk(value, set_flags, NULL);

	return 0;
}
U_BOOT_ENV_CALLBACK(flags, on_flags);

/*
 * Perform consistency checking before creating, overwriting, or deleting an
 * environment variable. Called as a callback function by hsearch_r() and
 * hdelete_r(). Returns 0 in case of success, 1 in case of failure.
 * When (flag & H_FORCE) is set, do not print out any error message and force
 * overwriting of write-once variables.
 */

int env_flags_validate(const ENTRY *item, const char *newval, enum env_op op,
	int flag)
{
	const char *name;
	const char *oldval = NULL;

	if (op != env_op_create)
		oldval = item->data;

	name = item->key;

	/* Default value for NULL to protect string-manipulating functions */
	newval = newval ? : "";

	/* validate the value to match the variable type */
	if (op != env_op_delete) {
		enum env_flags_vartype type = (enum env_flags_vartype)
			(ENV_FLAGS_VARTYPE_BIN_MASK & item->flags);

		if (_env_flags_validate_type(newval, type) < 0) {
			printf("## Error: flags type check failure for "
				"\"%s\" <= \"%s\" (type: %c)\n",
				name, newval, env_flags_vartype_rep[type]);
			return -1;
		}
	}

	/* check for access permission */
#ifndef CONFIG_ENV_ACCESS_IGNORE_FORCE
	if (flag & H_FORCE)
		return 0;
#endif
	switch (op) {
	case env_op_delete:
		if (item->flags & ENV_FLAGS_VARACCESS_PREVENT_DELETE) {
			printf("## Error: Can't delete \"%s\"\n", name);
			return 1;
		}
		break;
	case env_op_overwrite:
		if (item->flags & ENV_FLAGS_VARACCESS_PREVENT_OVERWR) {
			printf("## Error: Can't overwrite \"%s\"\n", name);
			return 1;
		} else if (item->flags &
		    ENV_FLAGS_VARACCESS_PREVENT_NONDEF_OVERWR) {
			const char *defval = getenv_default(name);

			if (defval == NULL)
				defval = "";
			printf("oldval: %s  defval: %s\n", oldval, defval);
			if (strcmp(oldval, defval) != 0) {
				printf("## Error: Can't overwrite \"%s\"\n",
					name);
				return 1;
			}
		}
		break;
	case env_op_create:
		if (item->flags & ENV_FLAGS_VARACCESS_PREVENT_CREATE) {
			printf("## Error: Can't create \"%s\"\n", name);
			return 1;
		}
		break;
	}

	return 0;
}

#endif
Commit	Line	Data
2598090b JH	1	/*
	2	* (C) Copyright 2012
	3	* Joe Hershberger, National Instruments, [email protected]
	4	*
1a459660	5	* SPDX-License-Identifier: GPL-2.0+
2598090b JH	6	*/
	7
	8	#include <linux/string.h>
	9	#include <linux/ctype.h>
	10
30fd4fad JH	11	#ifdef USE_HOSTCC /* Eliminate "ANSI does not permit..." warnings */
	12	#include <stdint.h>
	13	#include <stdio.h>
	14	#include "fw_env.h"
	15	#include <env_attr.h>
	16	#include <env_flags.h>
	17	#define getenv fw_getenv
ed0f40a6	18	#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
30fd4fad	19	#else
2598090b JH	20	#include <common.h>
2598090b JH	21	#include <environment.h>
30fd4fad	22	#endif
2598090b JH	23
	24	#ifdef CONFIG_CMD_NET
	25	#define ENV_FLAGS_NET_VARTYPE_REPS "im"
	26	#else
	27	#define ENV_FLAGS_NET_VARTYPE_REPS ""
	28	#endif
	29
	30	static const char env_flags_vartype_rep[] = "sdxb" ENV_FLAGS_NET_VARTYPE_REPS;
267541f7 JH	31	static const char env_flags_varaccess_rep[] = "aroc";
	32	static const int env_flags_varaccess_mask[] = {
	33	0,
	34	ENV_FLAGS_VARACCESS_PREVENT_DELETE \|
	35	ENV_FLAGS_VARACCESS_PREVENT_CREATE \|
	36	ENV_FLAGS_VARACCESS_PREVENT_OVERWR,
	37	ENV_FLAGS_VARACCESS_PREVENT_DELETE \|
	38	ENV_FLAGS_VARACCESS_PREVENT_OVERWR,
	39	ENV_FLAGS_VARACCESS_PREVENT_DELETE \|
	40	ENV_FLAGS_VARACCESS_PREVENT_NONDEF_OVERWR};
	41
fffad71b JH	42	#ifdef CONFIG_CMD_ENV_FLAGS
	43	static const char * const env_flags_vartype_names[] = {
	44	"string",
	45	"decimal",
	46	"hexadecimal",
	47	"boolean",
	48	#ifdef CONFIG_CMD_NET
	49	"IP address",
	50	"MAC address",
	51	#endif
	52	};
267541f7 JH	53	static const char * const env_flags_varaccess_names[] = {
	54	"any",
	55	"read-only",
	56	"write-once",
	57	"change-default",
	58	};
fffad71b JH	59
	60	/*
	61	* Print the whole list of available type flags.
	62	*/
	63	void env_flags_print_vartypes(void)
	64	{
	65	enum env_flags_vartype curtype = (enum env_flags_vartype)0;
	66
	67	while (curtype != env_flags_vartype_end) {
	68	printf("\t%c -\t%s\n", env_flags_vartype_rep[curtype],
	69	env_flags_vartype_names[curtype]);
	70	curtype++;
	71	}
	72	}
	73
267541f7 JH	74	/*
	75	* Print the whole list of available access flags.
	76	*/
	77	void env_flags_print_varaccess(void)
	78	{
	79	enum env_flags_varaccess curaccess = (enum env_flags_varaccess)0;
	80
	81	while (curaccess != env_flags_varaccess_end) {
	82	printf("\t%c -\t%s\n", env_flags_varaccess_rep[curaccess],
	83	env_flags_varaccess_names[curaccess]);
	84	curaccess++;
	85	}
	86	}
	87
fffad71b JH	88	/*
	89	* Return the name of the type.
	90	*/
	91	const char *env_flags_get_vartype_name(enum env_flags_vartype type)
	92	{
	93	return env_flags_vartype_names[type];
	94	}
267541f7 JH	95
	96	/*
	97	* Return the name of the access.
	98	*/
	99	const char *env_flags_get_varaccess_name(enum env_flags_varaccess access)
	100	{
	101	return env_flags_varaccess_names[access];
	102	}
fffad71b	103	#endif /* CONFIG_CMD_ENV_FLAGS */
2598090b JH	104
	105	/*
	106	* Parse the flags string from a .flags attribute list into the vartype enum.
	107	*/
	108	enum env_flags_vartype env_flags_parse_vartype(const char *flags)
	109	{
	110	char *type;
	111
	112	if (strlen(flags) <= ENV_FLAGS_VARTYPE_LOC)
	113	return env_flags_vartype_string;
	114
	115	type = strchr(env_flags_vartype_rep,
	116	flags[ENV_FLAGS_VARTYPE_LOC]);
	117
	118	if (type != NULL)
	119	return (enum env_flags_vartype)
	120	(type - &env_flags_vartype_rep[0]);
	121
	122	printf("## Warning: Unknown environment variable type '%c'\n",
	123	flags[ENV_FLAGS_VARTYPE_LOC]);
	124	return env_flags_vartype_string;
	125	}
	126
267541f7 JH	127	/*
	128	* Parse the flags string from a .flags attribute list into the varaccess enum.
	129	*/
	130	enum env_flags_varaccess env_flags_parse_varaccess(const char *flags)
	131	{
	132	char *access;
	133
	134	if (strlen(flags) <= ENV_FLAGS_VARACCESS_LOC)
	135	return env_flags_varaccess_any;
	136
	137	access = strchr(env_flags_varaccess_rep,
	138	flags[ENV_FLAGS_VARACCESS_LOC]);
	139
	140	if (access != NULL)
	141	return (enum env_flags_varaccess)
	142	(access - &env_flags_varaccess_rep[0]);
	143
	144	printf("## Warning: Unknown environment variable access method '%c'\n",
	145	flags[ENV_FLAGS_VARACCESS_LOC]);
	146	return env_flags_varaccess_any;
	147	}
	148
	149	/*
	150	* Parse the binary flags from a hash table entry into the varaccess enum.
	151	*/
	152	enum env_flags_varaccess env_flags_parse_varaccess_from_binflags(int binflags)
	153	{
	154	int i;
	155
db18f548	156	for (i = 0; i < ARRAY_SIZE(env_flags_varaccess_mask); i++)
267541f7 JH	157	if (env_flags_varaccess_mask[i] ==
	158	(binflags & ENV_FLAGS_VARACCESS_BIN_MASK))
	159	return (enum env_flags_varaccess)i;
	160
	161	printf("Warning: Non-standard access flags. (0x%x)\n",
	162	binflags & ENV_FLAGS_VARACCESS_BIN_MASK);
	163
	164	return env_flags_varaccess_any;
	165	}
	166
2598090b JH	167	static inline int is_hex_prefix(const char *value)
	168	{
	169	return value[0] == '0' && (value[1] == 'x' \|\| value[1] == 'X');
	170	}
	171
	172	static void skip_num(int hex, const char value, const char *end,
	173	int max_digits)
	174	{
	175	int i;
	176
	177	if (hex && is_hex_prefix(value))
	178	value += 2;
	179
	180	for (i = max_digits; i != 0; i--) {
	181	if (hex && !isxdigit(*value))
	182	break;
	183	if (!hex && !isdigit(*value))
	184	break;
	185	value++;
	186	}
	187	if (end != NULL)
	188	*end = value;
	189	}
	190
0118e83b CC	191	#ifdef CONFIG_CMD_NET
	192	int eth_validate_ethaddr_str(const char *addr)
	193	{
	194	const char *end;
	195	const char *cur;
	196	int i;
	197
	198	cur = addr;
	199	for (i = 0; i < 6; i++) {
	200	skip_num(1, cur, &end, 2);
	201	if (cur == end)
	202	return -1;
	203	if (cur + 2 == end && is_hex_prefix(cur))
	204	return -1;
	205	if (i != 5 && *end != ':')
	206	return -1;
	207	if (i == 5 && *end != '\0')
	208	return -1;
	209	cur = end + 1;
	210	}
	211
	212	return 0;
	213	}
	214	#endif
	215
2598090b JH	216	/*
	217	* Based on the declared type enum, validate that the value string complies
	218	* with that format
	219	*/
	220	static int _env_flags_validate_type(const char *value,
	221	enum env_flags_vartype type)
	222	{
	223	const char *end;
	224	#ifdef CONFIG_CMD_NET
	225	const char *cur;
	226	int i;
	227	#endif
	228
	229	switch (type) {
	230	case env_flags_vartype_string:
	231	break;
	232	case env_flags_vartype_decimal:
	233	skip_num(0, value, &end, -1);
	234	if (*end != '\0')
	235	return -1;
	236	break;
	237	case env_flags_vartype_hex:
	238	skip_num(1, value, &end, -1);
	239	if (*end != '\0')
	240	return -1;
	241	if (value + 2 == end && is_hex_prefix(value))
	242	return -1;
	243	break;
	244	case env_flags_vartype_bool:
	245	if (value[0] != '1' && value[0] != 'y' && value[0] != 't' &&
	246	value[0] != 'Y' && value[0] != 'T' &&
	247	value[0] != '0' && value[0] != 'n' && value[0] != 'f' &&
	248	value[0] != 'N' && value[0] != 'F')
	249	return -1;
	250	if (value[1] != '\0')
	251	return -1;
	252	break;
	253	#ifdef CONFIG_CMD_NET
	254	case env_flags_vartype_ipaddr:
	255	cur = value;
	256	for (i = 0; i < 4; i++) {
	257	skip_num(0, cur, &end, 3);
	258	if (cur == end)
	259	return -1;
	260	if (i != 3 && *end != '.')
	261	return -1;
	262	if (i == 3 && *end != '\0')
	263	return -1;
	264	cur = end + 1;
	265	}
	266	break;
	267	case env_flags_vartype_macaddr:
0118e83b CC	268	if (eth_validate_ethaddr_str(value))
0118e83b CC	269	return -1;
2598090b JH	270	break;
	271	#endif
	272	case env_flags_vartype_end:
	273	return -1;
	274	}
	275
	276	/* OK */
	277	return 0;
	278	}
	279
	280	/*
	281	* Look for flags in a provided list and failing that the static list
	282	*/
	283	static inline int env_flags_lookup(const char flags_list, const char name,
	284	char *flags)
	285	{
	286	int ret = 1;
	287
	288	if (!flags)
	289	/* bad parameter */
	290	return -1;
	291
	292	/* try the env first */
	293	if (flags_list)
	294	ret = env_attr_lookup(flags_list, name, flags);
	295
	296	if (ret != 0)
	297	/* if not found in the env, look in the static list */
	298	ret = env_attr_lookup(ENV_FLAGS_LIST_STATIC, name, flags);
	299
	300	return ret;
	301	}
	302
30fd4fad JH	303	#ifdef USE_HOSTCC /* Functions only used from tools/env */
	304	/*
	305	* Look up any flags directly from the .flags variable and the static list
	306	* and convert them to the vartype enum.
	307	*/
	308	enum env_flags_vartype env_flags_get_type(const char *name)
	309	{
	310	const char *flags_list = getenv(ENV_FLAGS_VAR);
	311	char flags[ENV_FLAGS_ATTR_MAX_LEN + 1];
	312
	313	if (env_flags_lookup(flags_list, name, flags))
	314	return env_flags_vartype_string;
	315
	316	if (strlen(flags) <= ENV_FLAGS_VARTYPE_LOC)
	317	return env_flags_vartype_string;
	318
	319	return env_flags_parse_vartype(flags);
	320	}
	321
267541f7 JH	322	/*
	323	* Look up the access of a variable directly from the .flags var.
	324	*/
	325	enum env_flags_varaccess env_flags_get_varaccess(const char *name)
	326	{
	327	const char *flags_list = getenv(ENV_FLAGS_VAR);
	328	char flags[ENV_FLAGS_ATTR_MAX_LEN + 1];
	329
	330	if (env_flags_lookup(flags_list, name, flags))
	331	return env_flags_varaccess_any;
	332
	333	if (strlen(flags) <= ENV_FLAGS_VARACCESS_LOC)
	334	return env_flags_varaccess_any;
	335
	336	return env_flags_parse_varaccess(flags);
	337	}
	338
30fd4fad JH	339	/*
	340	* Validate that the proposed new value for "name" is valid according to the
	341	* defined flags for that variable, if any.
	342	*/
	343	int env_flags_validate_type(const char name, const char value)
	344	{
	345	enum env_flags_vartype type;
	346
	347	if (value == NULL)
	348	return 0;
	349	type = env_flags_get_type(name);
	350	if (_env_flags_validate_type(value, type) < 0) {
	351	printf("## Error: flags type check failure for "
	352	"\"%s\" <= \"%s\" (type: %c)\n",
	353	name, value, env_flags_vartype_rep[type]);
	354	return -1;
	355	}
	356	return 0;
	357	}
	358
267541f7 JH	359	/*
	360	* Validate that the proposed access to variable "name" is valid according to
	361	* the defined flags for that variable, if any.
	362	*/
	363	int env_flags_validate_varaccess(const char *name, int check_mask)
	364	{
	365	enum env_flags_varaccess access;
	366	int access_mask;
	367
	368	access = env_flags_get_varaccess(name);
	369	access_mask = env_flags_varaccess_mask[access];
	370
	371	return (check_mask & access_mask) != 0;
	372	}
	373
30fd4fad JH	374	/*
	375	* Validate the parameters to "env set" directly
	376	*/
167f5258	377	int env_flags_validate_env_set_params(char name, char const val[], int count)
30fd4fad	378	{
167f5258 AF	379	if ((count >= 1) && val[0] != NULL) {
167f5258 AF	380	enum env_flags_vartype type = env_flags_get_type(name);
30fd4fad JH	381
	382	/*
	383	* we don't currently check types that need more than
	384	* one argument
	385	*/
167f5258 AF	386	if (type != env_flags_vartype_string && count > 1) {
	387	printf("## Error: too many parameters for setting \"%s\"\n",
	388	name);
30fd4fad JH	389	return -1;
30fd4fad JH	390	}
167f5258	391	return env_flags_validate_type(name, val[0]);
30fd4fad JH	392	}
	393	/* ok */
	394	return 0;
	395	}
	396
	397	#else /* !USE_HOSTCC - Functions only used from lib/hashtable.c */
	398
2598090b JH	399	/*
	400	* Parse the flag charachters from the .flags attribute list into the binary
	401	* form to be stored in the environment entry->flags field.
	402	*/
	403	static int env_parse_flags_to_bin(const char *flags)
	404	{
267541f7 JH	405	int binflags;
	406
	407	binflags = env_flags_parse_vartype(flags) & ENV_FLAGS_VARTYPE_BIN_MASK;
	408	binflags \|= env_flags_varaccess_mask[env_flags_parse_varaccess(flags)];
	409
	410	return binflags;
2598090b JH	411	}
2598090b JH	412
1b610271 HS	413	static int first_call = 1;
	414	static const char *flags_list;
	415
2598090b JH	416	/*
	417	* Look for possible flags for a newly added variable
	418	* This is called specifically when the variable did not exist in the hash
	419	* previously, so the blanket update did not find this variable.
	420	*/
	421	void env_flags_init(ENTRY *var_entry)
	422	{
	423	const char *var_name = var_entry->key;
2598090b JH	424	char flags[ENV_FLAGS_ATTR_MAX_LEN + 1] = "";
	425	int ret = 1;
	426
1b610271 HS	427	if (first_call) {
	428	flags_list = getenv(ENV_FLAGS_VAR);
	429	first_call = 0;
	430	}
2598090b JH	431	/* look in the ".flags" and static for a reference to this variable */
	432	ret = env_flags_lookup(flags_list, var_name, flags);
	433
	434	/* if any flags were found, set the binary form to the entry */
	435	if (!ret && strlen(flags))
	436	var_entry->flags = env_parse_flags_to_bin(flags);
	437	}
	438
	439	/*
	440	* Called on each existing env var prior to the blanket update since removing
	441	* a flag in the flag list should remove its flags.
	442	*/
	443	static int clear_flags(ENTRY *entry)
	444	{
	445	entry->flags = 0;
	446
	447	return 0;
	448	}
	449
	450	/*
	451	* Call for each element in the list that defines flags for a variable
	452	*/
cca98fd6	453	static int set_flags(const char name, const char value, void *priv)
2598090b JH	454	{
	455	ENTRY e, *ep;
	456
	457	e.key = name;
	458	e.data = NULL;
5a689439	459	e.callback = NULL;
2598090b JH	460	hsearch_r(e, FIND, &ep, &env_htab, 0);
	461
	462	/* does the env variable actually exist? */
	463	if (ep != NULL) {
	464	/* the flag list is empty, so clear the flags */
	465	if (value == NULL \|\| strlen(value) == 0)
	466	ep->flags = 0;
	467	else
	468	/* assign the requested flags */
	469	ep->flags = env_parse_flags_to_bin(value);
	470	}
	471
	472	return 0;
	473	}
	474
	475	static int on_flags(const char name, const char value, enum env_op op,
	476	int flags)
	477	{
	478	/* remove all flags */
	479	hwalk_r(&env_htab, clear_flags);
	480
	481	/* configure any static flags */
cca98fd6	482	env_attr_walk(ENV_FLAGS_LIST_STATIC, set_flags, NULL);
2598090b	483	/* configure any dynamic flags */
cca98fd6	484	env_attr_walk(value, set_flags, NULL);
2598090b JH	485
	486	return 0;
	487	}
	488	U_BOOT_ENV_CALLBACK(flags, on_flags);
	489
	490	/*
	491	* Perform consistency checking before creating, overwriting, or deleting an
	492	* environment variable. Called as a callback function by hsearch_r() and
	493	* hdelete_r(). Returns 0 in case of success, 1 in case of failure.
	494	* When (flag & H_FORCE) is set, do not print out any error message and force
	495	* overwriting of write-once variables.
	496	*/
	497
	498	int env_flags_validate(const ENTRY item, const char newval, enum env_op op,
	499	int flag)
	500	{
	501	const char *name;
2598090b JH	502	const char *oldval = NULL;
	503
	504	if (op != env_op_create)
	505	oldval = item->data;
2598090b JH	506
	507	name = item->key;
	508
	509	/* Default value for NULL to protect string-manipulating functions */
	510	newval = newval ? : "";
	511
2598090b JH	512	/* validate the value to match the variable type */
	513	if (op != env_op_delete) {
	514	enum env_flags_vartype type = (enum env_flags_vartype)
	515	(ENV_FLAGS_VARTYPE_BIN_MASK & item->flags);
	516
	517	if (_env_flags_validate_type(newval, type) < 0) {
	518	printf("## Error: flags type check failure for "
	519	"\"%s\" <= \"%s\" (type: %c)\n",
	520	name, newval, env_flags_vartype_rep[type]);
	521	return -1;
	522	}
	523	}
	524
267541f7 JH	525	/* check for access permission */
	526	#ifndef CONFIG_ENV_ACCESS_IGNORE_FORCE
	527	if (flag & H_FORCE)
	528	return 0;
	529	#endif
	530	switch (op) {
	531	case env_op_delete:
	532	if (item->flags & ENV_FLAGS_VARACCESS_PREVENT_DELETE) {
	533	printf("## Error: Can't delete \"%s\"\n", name);
	534	return 1;
	535	}
	536	break;
	537	case env_op_overwrite:
	538	if (item->flags & ENV_FLAGS_VARACCESS_PREVENT_OVERWR) {
	539	printf("## Error: Can't overwrite \"%s\"\n", name);
	540	return 1;
	541	} else if (item->flags &
	542	ENV_FLAGS_VARACCESS_PREVENT_NONDEF_OVERWR) {
	543	const char *defval = getenv_default(name);
	544
	545	if (defval == NULL)
	546	defval = "";
	547	printf("oldval: %s defval: %s\n", oldval, defval);
	548	if (strcmp(oldval, defval) != 0) {
	549	printf("## Error: Can't overwrite \"%s\"\n",
	550	name);
	551	return 1;
	552	}
	553	}
	554	break;
	555	case env_op_create:
	556	if (item->flags & ENV_FLAGS_VARACCESS_PREVENT_CREATE) {
	557	printf("## Error: Can't create \"%s\"\n", name);
	558	return 1;
	559	}
	560	break;
	561	}
	562
2598090b JH	563	return 0;
2598090b JH	564	}
30fd4fad JH	565
30fd4fad JH	566	#endif