diff options
Diffstat (limited to 'contrib/syslinux/syslinux-4.03/libinstaller/setadv.c')
| -rw-r--r-- | contrib/syslinux/syslinux-4.03/libinstaller/setadv.c | 167 |
1 files changed, 0 insertions, 167 deletions
diff --git a/contrib/syslinux/syslinux-4.03/libinstaller/setadv.c b/contrib/syslinux/syslinux-4.03/libinstaller/setadv.c deleted file mode 100644 index 9cf6f18..0000000 --- a/contrib/syslinux/syslinux-4.03/libinstaller/setadv.c +++ /dev/null @@ -1,167 +0,0 @@ -/* ----------------------------------------------------------------------- * - * - * Copyright 2007-2008 H. Peter Anvin - All Rights Reserved - * Copyright 2010 Intel Corporation; author: H. Peter Anvin - * - * 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, Inc., 53 Temple Place Ste 330, - * Boston MA 02111-1307, USA; either version 2 of the License, or - * (at your option) any later version; incorporated herein by reference. - * - * ----------------------------------------------------------------------- */ - -/* - * setadv.c - * - * (Over)write a data item in the auxilliary data vector. To - * delete an item, set its length to zero. - * - * Return 0 on success, -1 on error, and set errno. - * - */ -#define _GNU_SOURCE - -#include <stdio.h> -#include <stdlib.h> -#include <stddef.h> -#include <stdint.h> -#include <string.h> -#include <errno.h> -#include "syslxint.h" -#include "syslxcom.h" - -unsigned char syslinux_adv[2 * ADV_SIZE]; - -#define ADV_MAGIC1 0x5a2d2fa5 /* Head signature */ -#define ADV_MAGIC2 0xa3041767 /* Total checksum */ -#define ADV_MAGIC3 0xdd28bf64 /* Tail signature */ - -static void cleanup_adv(unsigned char *advbuf) -{ - int i; - uint32_t csum; - - /* Make sure both copies agree, and update the checksum */ - set_32((uint32_t *) advbuf, ADV_MAGIC1); - - csum = ADV_MAGIC2; - for (i = 8; i < ADV_SIZE - 4; i += 4) - csum -= get_32((uint32_t *) (advbuf + i)); - - set_32((uint32_t *) (advbuf + 4), csum); - set_32((uint32_t *) (advbuf + ADV_SIZE - 4), ADV_MAGIC3); - - memcpy(advbuf + ADV_SIZE, advbuf, ADV_SIZE); -} - -int syslinux_setadv(int tag, size_t size, const void *data) -{ - uint8_t *p; - size_t left; - uint8_t advtmp[ADV_SIZE]; - - if ((unsigned)tag - 1 > 254) { - errno = EINVAL; - return -1; /* Impossible tag value */ - } - - if (size > 255) { - errno = ENOSPC; /* Max 255 bytes for a data item */ - return -1; - } - - left = ADV_LEN; - p = advtmp; - memcpy(p, syslinux_adv + 2 * 4, left); /* Make working copy */ - - while (left >= 2) { - uint8_t ptag = p[0]; - size_t plen = p[1] + 2; - - if (ptag == ADV_END) - break; - - if (ptag == tag) { - /* Found our tag. Delete it. */ - - if (plen >= left) { - /* Entire remainder is our tag */ - break; - } - memmove(p, p + plen, left - plen); - } else { - /* Not our tag */ - if (plen > left) - break; /* Corrupt tag (overrun) - overwrite it */ - - left -= plen; - p += plen; - } - } - - /* Now (p, left) reflects the position to write in and how much space - we have for our data. */ - - if (size) { - if (left < size + 2) { - errno = ENOSPC; /* Not enough space for data */ - return -1; - } - - *p++ = tag; - *p++ = size; - memcpy(p, data, size); - p += size; - left -= size + 2; - } - - memset(p, 0, left); - - /* If we got here, everything went OK, commit the write */ - memcpy(syslinux_adv + 2 * 4, advtmp, ADV_LEN); - cleanup_adv(syslinux_adv); - - return 0; -} - -void syslinux_reset_adv(unsigned char *advbuf) -{ - /* Create an all-zero ADV */ - memset(advbuf + 2 * 4, 0, ADV_LEN); - cleanup_adv(advbuf); -} - -static int adv_consistent(const unsigned char *p) -{ - int i; - uint32_t csum; - - if (get_32((uint32_t *) p) != ADV_MAGIC1 || - get_32((uint32_t *) (p + ADV_SIZE - 4)) != ADV_MAGIC3) - return 0; - - csum = 0; - for (i = 4; i < ADV_SIZE - 4; i += 4) - csum += get_32((uint32_t *) (p + i)); - - return csum == ADV_MAGIC2; -} - -/* - * Verify that an in-memory ADV is consistent, making the copies consistent. - * If neither copy is OK, return -1 and call syslinux_reset_adv(). - */ -int syslinux_validate_adv(unsigned char *advbuf) -{ - if (adv_consistent(advbuf + 0 * ADV_SIZE)) { - memcpy(advbuf + ADV_SIZE, advbuf, ADV_SIZE); - return 0; - } else if (adv_consistent(advbuf + 1 * ADV_SIZE)) { - memcpy(advbuf, advbuf + ADV_SIZE, ADV_SIZE); - return 0; - } else { - syslinux_reset_adv(advbuf); - return -1; - } -} |