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New API call iso_md5_match().
This commit is contained in:
Thomas Schmitt
2009-08-18 17:03:33 +02:00
parent 868005ed0e
commit 8b800094af
6 changed files with 249 additions and 25 deletions
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86
libisofs/util.c
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@ -9,6 +9,7 @@
#include "util.h"
#include "libisofs.h"
#include "messages.h"
#include "../version.h"
#include <stdlib.h>
@ -1563,18 +1564,33 @@ int iso_util_hex_to_bin(char *hex, char *bin, int bin_size, int *bin_count,
}
int iso_util_tag_magic(int tag_type, char **tag_magic, int *len, int flag)
{
static char *magic[] = {"",
"libisofs_checksum_tag_v1",
"libisofs_sb_checksum_tag_v1",
"libisofs_tree_checksum_tag_v1",
"libisofs_rlsb32_checksum_tag_v1"};
static int magic_len[]= {0, 24, 27, 29, 31};
static int magic_max = 4;
*tag_magic = NULL;
*len = 0;
if (tag_type < 0 || tag_type > magic_max)
return ISO_WRONG_ARG_VALUE;
*tag_magic = magic[tag_type];
*len = magic_len[tag_type];
return magic_max;
}
int iso_util_decode_md5_tag(char data[2048], int *tag_type, uint32_t *pos,
uint32_t *range_start, uint32_t *range_size,
uint32_t *next_tag, char md5[16], int flag)
{
static char *tag_magic[] = {"",
"libisofs_checksum_tag_v1",
"libisofs_sb_checksum_tag_v1",
"libisofs_tree_checksum_tag_v1",
"libisofs_rlsb32_checksum_tag_v1"};
static int magic_len[]= {0, 24, 27, 29, 31};
int ret, bin_count, i, mode, magic_first = 1, magic_last = 4;
char *cpt, self_md5[16], tag_md5[16];
int magic_len = 0;
char *cpt, self_md5[16], tag_md5[16], *tag_magic;
void *ctx = NULL;
*next_tag = 0;
@ -1583,13 +1599,15 @@ int iso_util_decode_md5_tag(char data[2048], int *tag_type, uint32_t *pos,
return ISO_WRONG_ARG_VALUE;
if (mode > 0)
magic_first = magic_last = mode;
for (i = magic_first; i <= magic_last; i++)
if (strncmp(data, tag_magic[i], magic_len[i]) == 0)
for (i = magic_first; i <= magic_last; i++) {
iso_util_tag_magic(i, &tag_magic, &magic_len, 0);
if (strncmp(data, tag_magic, magic_len) == 0)
break;
}
if (i > magic_last )
return 0;
*tag_type = i;
cpt = data + magic_len[*tag_type] + 1;
cpt = data + magic_len + 1;
if (strncmp(cpt, "pos=", 4) != 0)
return 0;
cpt+= 4;
@ -1650,3 +1668,51 @@ int iso_util_decode_md5_tag(char data[2048], int *tag_type, uint32_t *pos,
return(1);
}
int iso_util_eval_md5_tag(char *block, int desired, uint32_t lba,
void *ctx, uint32_t ctx_start_lba,
int *tag_type, uint32_t *next_tag, int flag)
{
int decode_ret, ret;
char md5[16], cloned_md5[16];
uint32_t pos, range_start, range_size;
void *cloned_ctx = NULL;
*tag_type = 0;
decode_ret = iso_util_decode_md5_tag(block, tag_type, &pos,
&range_start, &range_size, next_tag, md5, 0);
if (decode_ret != 1 && decode_ret != ISO_MD5_AREA_CORRUPTED)
return 0;
if (*tag_type > 30)
goto unexpected_type;
if (decode_ret == ISO_MD5_AREA_CORRUPTED) {
ret = decode_ret;
goto ex;
} else if (!((1 << *tag_type) & desired)) {
unexpected_type:;
iso_msg_submit(-1, ISO_MD5_TAG_UNEXPECTED, 0, NULL);
ret = 0;
goto ex;
} else if(pos != lba) {
ret = ISO_MD5_TAG_MISPLACED;
goto ex;
} else if(range_start != ctx_start_lba) {
ret = ISO_MD5_TAG_MISPLACED;
}
ret = iso_md5_clone(ctx, &cloned_ctx);
if (ret < 0)
goto ex;
iso_md5_end(&cloned_ctx, cloned_md5);
if (! iso_md5_match(cloned_md5, md5)) {
ret = ISO_MD5_TAG_MISMATCH;
goto ex;
}
ret = 1;
ex:;
if (ret < 0)
iso_msg_submit(-1, ret, 0, NULL);
return ret;
}