core: protect precomputed block hashes with SHA256

This commit is contained in:
moneromooo-monero 2017-02-23 23:18:10 +00:00
parent d666339853
commit 583a7b5c74
No known key found for this signature in database
GPG key ID: 686F07454D6CEFC3
3 changed files with 41 additions and 1 deletions

View file

@ -587,6 +587,18 @@ std::string get_nix_version_display_string()
return 0; return 0;
} }
bool sha256sum(const uint8_t *data, size_t len, crypto::hash &hash)
{
SHA256_CTX ctx;
if (!SHA256_Init(&ctx))
return false;
if (!SHA256_Update(&ctx, data, len))
return false;
if (!SHA256_Final((unsigned char*)hash.data, &ctx))
return false;
return true;
}
bool sha256sum(const std::string &filename, crypto::hash &hash) bool sha256sum(const std::string &filename, crypto::hash &hash)
{ {
if (!epee::file_io_utils::is_file_exist(filename)) if (!epee::file_io_utils::is_file_exist(filename))

View file

@ -185,5 +185,6 @@ namespace tools
bool is_local_address(const std::string &address); bool is_local_address(const std::string &address);
int vercmp(const char *v0, const char *v1); // returns < 0, 0, > 0, similar to strcmp, but more human friendly than lexical - does not attempt to validate int vercmp(const char *v0, const char *v1); // returns < 0, 0, > 0, similar to strcmp, but more human friendly than lexical - does not attempt to validate
bool sha256sum(const uint8_t *data, size_t len, crypto::hash &hash);
bool sha256sum(const std::string &filename, crypto::hash &hash); bool sha256sum(const std::string &filename, crypto::hash &hash);
} }

View file

@ -3995,10 +3995,37 @@ void Blockchain::cancel()
} }
#if defined(PER_BLOCK_CHECKPOINT) #if defined(PER_BLOCK_CHECKPOINT)
static const char expected_block_hashes_hash[] = "23d8a8c73de7b2383c72a016d9a6034e69d62dd48077d1c414e064ceab6daa94";
void Blockchain::load_compiled_in_block_hashes() void Blockchain::load_compiled_in_block_hashes()
{ {
if (m_fast_sync && get_blocks_dat_start(m_testnet) != nullptr) if (m_fast_sync && get_blocks_dat_start(m_testnet) != nullptr)
{ {
MINFO("Loading precomputed blocks (" << get_blocks_dat_size(m_testnet) << " bytes)");
if (!m_testnet)
{
// first check hash
crypto::hash hash;
if (!tools::sha256sum(get_blocks_dat_start(m_testnet), get_blocks_dat_size(m_testnet), hash))
{
MERROR("Failed to hash precomputed blocks data");
return;
}
MINFO("precomputed blocks hash: " << hash << ", expected " << expected_block_hashes_hash);
cryptonote::blobdata expected_hash_data;
if (!epee::string_tools::parse_hexstr_to_binbuff(std::string(expected_block_hashes_hash), expected_hash_data) || expected_hash_data.size() != sizeof(crypto::hash))
{
MERROR("Failed to parse expected block hashes hash");
return;
}
const crypto::hash expected_hash = *reinterpret_cast<const crypto::hash*>(expected_hash_data.data());
if (hash != expected_hash)
{
MERROR("Block hash data does not match expected hash");
return;
}
}
if (get_blocks_dat_size(m_testnet) > 4) if (get_blocks_dat_size(m_testnet) > 4)
{ {
const unsigned char *p = get_blocks_dat_start(m_testnet); const unsigned char *p = get_blocks_dat_start(m_testnet);
@ -4006,7 +4033,6 @@ void Blockchain::load_compiled_in_block_hashes()
const size_t size_needed = 4 + nblocks * sizeof(crypto::hash); const size_t size_needed = 4 + nblocks * sizeof(crypto::hash);
if(nblocks > 0 && nblocks > m_db->height() && get_blocks_dat_size(m_testnet) >= size_needed) if(nblocks > 0 && nblocks > m_db->height() && get_blocks_dat_size(m_testnet) >= size_needed)
{ {
MINFO("Loading precomputed blocks: " << nblocks);
p += sizeof(uint32_t); p += sizeof(uint32_t);
for (uint32_t i = 0; i < nblocks; i++) for (uint32_t i = 0; i < nblocks; i++)
{ {
@ -4015,6 +4041,7 @@ void Blockchain::load_compiled_in_block_hashes()
p += sizeof(hash.data); p += sizeof(hash.data);
m_blocks_hash_check.push_back(hash); m_blocks_hash_check.push_back(hash);
} }
MINFO(nblocks << " block hashes loaded");
// FIXME: clear tx_pool because the process might have been // FIXME: clear tx_pool because the process might have been
// terminated and caused it to store txs kept by blocks. // terminated and caused it to store txs kept by blocks.