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elftosb: implement encryption support; now fully working

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git-svn-id: svn://svn.rockbox.org/rockbox/trunk@29743 a1c6a512-1295-4272-9138-f99709370657
This commit is contained in:
Amaury Pouly 2011-04-17 23:28:18 +00:00
parent b2c59541b4
commit 84c70b2c5b
1 changed files with 42 additions and 4 deletions
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46
utils/sbtools/elftosb.c
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@ -843,6 +843,10 @@ static void produce_sb_file(struct sb_file_t *sb, const char *filename)
bugp("cannot open output file");
byte real_key[16];
byte (*cbc_macs)[16] = xmalloc(16 * g_nr_keys);
/* init CBC-MACs */
for(int i = 0; i < g_nr_keys; i++)
memset(cbc_macs[i], 0, 16);
fill_gaps(sb);
compute_sb_offsets(sb);
@ -857,6 +861,10 @@ static void produce_sb_file(struct sb_file_t *sb, const char *filename)
produce_sb_header(sb, &sb_hdr);
sha_1_update(&file_sha1, (byte *)&sb_hdr, sizeof(sb_hdr));
write(fd, &sb_hdr, sizeof(sb_hdr));
/* update CBC-MACs */
for(int i = 0; i < g_nr_keys; i++)
cbc_mac((byte *)&sb_hdr, NULL, sizeof(sb_hdr) / BLOCK_SIZE, g_key_array[i],
cbc_macs[i], &cbc_macs[i], 1);
/* produce and write section headers */
for(int i = 0; i < sb_hdr.nr_sections; i++)
@ -865,32 +873,60 @@ static void produce_sb_file(struct sb_file_t *sb, const char *filename)
produce_sb_section_header(&sb->sections[i], &sb_sec_hdr);
sha_1_update(&file_sha1, (byte *)&sb_sec_hdr, sizeof(sb_sec_hdr));
write(fd, &sb_sec_hdr, sizeof(sb_sec_hdr));
/* update CBC-MACs */
for(int j = 0; j < g_nr_keys; j++)
cbc_mac((byte *)&sb_sec_hdr, NULL, sizeof(sb_sec_hdr) / BLOCK_SIZE,
g_key_array[j], cbc_macs[j], &cbc_macs[j], 1);
}
/* produce key dictionary */
for(int i = 0; i < g_nr_keys; i++)
{
struct sb_key_dictionary_entry_t entry;
memcpy(entry.hdr_cbc_mac, cbc_macs[i], 16);
cbc_mac(real_key, entry.key, sizeof(real_key) / BLOCK_SIZE, g_key_array[i],
(byte *)&sb_hdr, NULL, 1);
write(fd, &entry, sizeof(entry));
sha_1_update(&file_sha1, (byte *)&entry, sizeof(entry));
}
/* produce sections data */
for(int i = 0; i< sb_hdr.nr_sections; i++)
{
/* produce tag command */
struct sb_instruction_tag_t tag_cmd;
produce_section_tag_cmd(&sb->sections[i], &tag_cmd, (i + 1) == sb_hdr.nr_sections);
if(g_nr_keys > 0)
cbc_mac((byte *)&tag_cmd, (byte *)&tag_cmd, sizeof(tag_cmd) / BLOCK_SIZE,
real_key, (byte *)&sb_hdr, NULL, 1);
sha_1_update(&file_sha1, (byte *)&tag_cmd, sizeof(tag_cmd));
write(fd, &tag_cmd, sizeof(tag_cmd));
/* produce other commands */
byte cur_cbc_mac[16];
memcpy(cur_cbc_mac, (byte *)&sb_hdr, 16);
for(int j = 0; j < sb->sections[i].nr_insts; j++)
{
struct sb_inst_t *inst = &sb->sections[i].insts[j];
/* command */
struct sb_instruction_common_t cmd;
produce_sb_instruction(inst, &cmd);
if(g_nr_keys > 0)
cbc_mac((byte *)&cmd, (byte *)&cmd, sizeof(cmd) / BLOCK_SIZE,
real_key, cur_cbc_mac, &cur_cbc_mac, 1);
sha_1_update(&file_sha1, (byte *)&cmd, sizeof(cmd));
write(fd, &cmd, sizeof(cmd));
/* data */
if(inst->inst == SB_INST_LOAD)
{
sha_1_update(&file_sha1, inst->data, inst->size);
write(fd, inst->data, inst->size);
sha_1_update(&file_sha1, inst->padding, inst->padding_size);
write(fd, inst->padding, inst->padding_size);
uint32_t sz = inst->size + inst->padding_size;
byte *data = xmalloc(sz);
memcpy(data, inst->data, inst->size);
memcpy(data + inst->size, inst->padding, inst->padding_size);
if(g_nr_keys > 0)
cbc_mac(data, data, sz / BLOCK_SIZE,
real_key, cur_cbc_mac, &cur_cbc_mac, 1);
sha_1_update(&file_sha1, data, sz);
write(fd, data, sz);
free(data);
}
}
}
@ -899,6 +935,8 @@ static void produce_sb_file(struct sb_file_t *sb, const char *filename)
sha_1_finish(&file_sha1);
sha_1_output(&file_sha1, final_sig);
generate_random_data(final_sig + 20, 12);
if(g_nr_keys > 0)
cbc_mac(final_sig, final_sig, 2, real_key, (byte *)&sb_hdr, NULL, 1);
write(fd, final_sig, 32);
close(fd);