Mirrors/MeshCore-Solo
1
0
Fork 0
mirror of https://github.com/MarekZegare4/MeshCore-Solo.git synced 2026-11-02 19:02:00 +00:00
Code Issues Packages Projects Releases Wiki Activity

Merge pull request #1809 from DanielNovak/fix-decrypt-block-alignment-check

Browse Source 
Fix stack buffer overflow in MACThenDecrypt
This commit is contained in:
Liam Cottle
2026-09-28 13:41:02 +13:00
committed by GitHub
parent db7a5f942f b74ba54530
commit b9f519ef5a
2 changed files with 6 additions and 3 deletions
Download Patch File Download Diff File Expand all files Collapse all files
src/Utils.cpp
+5 -2
View File
@@ -147,6 +147,9 @@ int Utils::encryptThenMAC(const uint8_t* shared_secret, uint8_t* dest, const uin
int Utils::MACThenDecrypt(const uint8_t* shared_secret, uint8_t* dest, const uint8_t* src, int src_len) { int Utils::MACThenDecrypt(const uint8_t* shared_secret, uint8_t* dest, const uint8_t* src, int src_len) {
if (src_len <= CIPHER_MAC_SIZE) return 0; // invalid src bytes if (src_len <= CIPHER_MAC_SIZE) return 0; // invalid src bytes
int enc_len = src_len - CIPHER_MAC_SIZE;
if (enc_len % CIPHER_BLOCK_SIZE != 0) return 0; // reject non-block-aligned ciphertext
uint8_t hmac[CIPHER_MAC_SIZE]; uint8_t hmac[CIPHER_MAC_SIZE];
#ifdef USE_CC310_HW_CRYPTO #ifdef USE_CC310_HW_CRYPTO
{ {
@@ -161,12 +164,12 @@ int Utils::MACThenDecrypt(const uint8_t* shared_secret, uint8_t* dest, const uin
{ {
SHA256 sha; SHA256 sha;
sha.resetHMAC(shared_secret, PUB_KEY_SIZE); sha.resetHMAC(shared_secret, PUB_KEY_SIZE);
sha.update(src + CIPHER_MAC_SIZE, src_len - CIPHER_MAC_SIZE); sha.update(src + CIPHER_MAC_SIZE, enc_len);
sha.finalizeHMAC(shared_secret, PUB_KEY_SIZE, hmac, CIPHER_MAC_SIZE); sha.finalizeHMAC(shared_secret, PUB_KEY_SIZE, hmac, CIPHER_MAC_SIZE);
} }
#endif #endif
if (memcmp(hmac, src, CIPHER_MAC_SIZE) == 0) { if (memcmp(hmac, src, CIPHER_MAC_SIZE) == 0) {
return decrypt(shared_secret, dest, src + CIPHER_MAC_SIZE, src_len - CIPHER_MAC_SIZE); return decrypt(shared_secret, dest, src + CIPHER_MAC_SIZE, enc_len);
} }
return 0; // invalid HMAC return 0; // invalid HMAC
} }
src/Utils.h
+1 -1
View File
@@ -50,7 +50,7 @@ public:
/** /**
* \brief checks the MAC (in leading bytes of 'src'), then if valid, decrypts remaining bytes in src. * \brief checks the MAC (in leading bytes of 'src'), then if valid, decrypts remaining bytes in src.
* \returns zero if MAC is invalid, otherwise the length of decrypted bytes in 'dest' * \returns zero if MAC is invalid or ciphertext is not block-aligned, otherwise the length of decrypted bytes in 'dest'
*/ */
static int MACThenDecrypt(const uint8_t* shared_secret, uint8_t* dest, const uint8_t* src, int src_len); static int MACThenDecrypt(const uint8_t* shared_secret, uint8_t* dest, const uint8_t* src, int src_len);