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-rw-r--r--common/env_flags.c560
1 files changed, 560 insertions, 0 deletions
diff --git a/common/env_flags.c b/common/env_flags.c
new file mode 100644
index 0000000..336cae4
--- /dev/null
+++ b/common/env_flags.c
@@ -0,0 +1,560 @@
+/*
+ * (C) Copyright 2012
+ * Joe Hershberger, National Instruments, joe.hershberger@ni.com
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#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
+#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 < sizeof(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;
+}
+
+/*
+ * 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:
+ cur = value;
+ 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;
+ }
+ 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(int argc, char * const argv[])
+{
+ if ((argc >= 3) && argv[2] != NULL) {
+ enum env_flags_vartype type = env_flags_get_type(argv[1]);
+
+ /*
+ * we don't currently check types that need more than
+ * one argument
+ */
+ if (type != env_flags_vartype_string && argc > 3) {
+ printf("## Error: too many parameters for setting "
+ "\"%s\"\n", argv[1]);
+ return -1;
+ }
+ return env_flags_validate_type(argv[1], argv[2]);
+ }
+ /* 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;
+}
+
+/*
+ * 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;
+ const char *flags_list = getenv(ENV_FLAGS_VAR);
+ char flags[ENV_FLAGS_ATTR_MAX_LEN + 1] = "";
+ int ret = 1;
+
+ /* 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)
+{
+ ENTRY e, *ep;
+
+ e.key = name;
+ e.data = 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);
+ /* configure any dynamic flags */
+ env_attr_walk(value, set_flags);
+
+ 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