| 1 | /* |
| 2 | * Atheros AR71xx minimal nvram support |
| 3 | * |
| 4 | * Copyright (C) 2009 Gabor Juhos <juhosg@openwrt.org> |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify it |
| 7 | * under the terms of the GNU General Public License version 2 as published |
| 8 | * by the Free Software Foundation. |
| 9 | */ |
| 10 | |
| 11 | #include <linux/kernel.h> |
| 12 | #include <linux/vmalloc.h> |
| 13 | #include <linux/errno.h> |
| 14 | #include <linux/init.h> |
| 15 | #include <linux/string.h> |
| 16 | |
| 17 | #include "nvram.h" |
| 18 | |
| 19 | char *nvram_find_var(const char *name, const char *buf, unsigned buf_len) |
| 20 | { |
| 21 | unsigned len = strlen(name); |
| 22 | char *cur, *last; |
| 23 | |
| 24 | if (buf_len == 0 || len == 0) |
| 25 | return NULL; |
| 26 | |
| 27 | if (buf_len < len) |
| 28 | return NULL; |
| 29 | |
| 30 | if (len == 1) |
| 31 | return memchr(buf, (int) *name, buf_len); |
| 32 | |
| 33 | last = (char *) buf + buf_len - len; |
| 34 | for (cur = (char *) buf; cur <= last; cur++) |
| 35 | if (cur[0] == name[0] && memcmp(cur, name, len) == 0) |
| 36 | return cur + len; |
| 37 | |
| 38 | return NULL; |
| 39 | } |
| 40 | |
| 41 | int nvram_parse_mac_addr(const char *nvram, unsigned nvram_len, |
| 42 | const char *name, char *mac) |
| 43 | { |
| 44 | char *buf; |
| 45 | char *mac_str; |
| 46 | int ret; |
| 47 | int t; |
| 48 | |
| 49 | buf = vmalloc(nvram_len); |
| 50 | if (!buf) |
| 51 | return -ENOMEM; |
| 52 | |
| 53 | memcpy(buf, nvram, nvram_len); |
| 54 | buf[nvram_len - 1] = '\0'; |
| 55 | |
| 56 | mac_str = nvram_find_var(name, buf, nvram_len); |
| 57 | if (!mac_str) { |
| 58 | ret = -EINVAL; |
| 59 | goto free; |
| 60 | } |
| 61 | |
| 62 | t = sscanf(mac_str, "%02hhx:%02hhx:%02hhx:%02hhx:%02hhx:%02hhx", |
| 63 | &mac[0], &mac[1], &mac[2], &mac[3], &mac[4], &mac[5]); |
| 64 | |
| 65 | if (t != 6) { |
| 66 | ret = -EINVAL; |
| 67 | goto free; |
| 68 | } |
| 69 | |
| 70 | ret = 0; |
| 71 | |
| 72 | free: |
| 73 | vfree(buf); |
| 74 | return ret; |
| 75 | } |
| 76 | |
