Fix a crash or unbounded allocation in RSA_padding_add_PKCS1_PSS_mgf1
and RSA_verify_PKCS1_PSS_mgf1 with 512-bit RSA vs. sha-512.
@@ -54,6 +54,7 @@ int RSA_verify_PKCS1_PSS_mgf1(RSA *rsa, const unsigned char *mHash,
* Negative sLen has special meanings:
* -1 sLen == hLen
* -2 salt length is autorecovered from signature
+ * -3 salt length is maximized
* -N reserved
*/
if (sLen == RSA_PSS_SALTLEN_DIGEST)
@@ -73,9 +74,13 @@ int RSA_verify_PKCS1_PSS_mgf1(RSA *rsa, const unsigned char *mHash,
EM++;
emLen--;
}
+ if (emLen < hLen + 2) {
+ RSAerr(RSA_F_RSA_VERIFY_PKCS1_PSS_MGF1, RSA_R_DATA_TOO_LARGE);
+ goto err;
+ }
if (sLen == RSA_PSS_SALTLEN_MAX) {
sLen = emLen - hLen - 2;
- } else if (emLen < (hLen + sLen + 2)) { /* sLen can be small negative */
+ } else if (sLen > emLen - hLen - 2) { /* sLen can be small negative */
RSAerr(RSA_F_RSA_VERIFY_PKCS1_PSS_MGF1, RSA_R_DATA_TOO_LARGE);
goto err;
}
@@ -157,6 +162,7 @@ int RSA_padding_add_PKCS1_PSS_mgf1(RSA *rsa, unsigned char *EM,
* Negative sLen has special meanings:
* -1 sLen == hLen
* -2 salt length is maximized
+ * -3 same as above (on signing)
* -N reserved
*/
if (sLen == RSA_PSS_SALTLEN_DIGEST)
@@ -174,9 +180,14 @@ int RSA_padding_add_PKCS1_PSS_mgf1(RSA *rsa, unsigned char *EM,
*EM++ = 0;
emLen--;
}
+ if (emLen < hLen + 2) {
+ RSAerr(RSA_F_RSA_PADDING_ADD_PKCS1_PSS_MGF1,
+ RSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE);
+ goto err;
+ }
if (sLen == RSA_PSS_SALTLEN_MAX) {
sLen = emLen - hLen - 2;
- } else if (emLen < (hLen + sLen + 2)) {
+ } else if (sLen > emLen - hLen - 2) {
RSAerr(RSA_F_RSA_PADDING_ADD_PKCS1_PSS_MGF1,
RSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE);
goto err;
