mirror/mbedtls
1
0
Fork 0
mirror of https://github.com/Mbed-TLS/mbedtls.git synced 2025-03-30 07:20:59 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

X.509: Remove red'n bounds checks and zeroiz'n in OtherName parsing

Browse Source 
- ASN.1 parsing functions check that length don't exceed buffer bounds,
  so checks `p + len > end` are redundant.
- If `p + len == end`, this is erroneous because we expect further fields,
  which is automatically caught by the next ASN.1 parsing call.

Hence, the two branches handling `p + len >= end` in x509_get_other_name()
can be removed.

Further, zeroization of the `other_name` structure isn't necessary
because it's not confidential (and it's also not performed on other
error conditions in this function).
Signed-off-by: Andrzej Kurek <andrzej.kurek@arm.com>
This commit is contained in:
Hanno Becker 2019-09-13 14:19:03 +01:00 committed by Andrzej Kurek
parent 5d82c3b99c
commit 2a15a0c868
1 changed files with 0 additions and 12 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
library/x509.c
View File

@ -1156,11 +1156,6 @@ static int x509_get_other_name(const mbedtls_x509_buf *subject_alt_name,
return MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE;
}
if (p + len >= end) {
mbedtls_platform_zeroize(other_name, sizeof(*other_name));
return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
}
p += len;
if ((ret = mbedtls_asn1_get_tag(&p, end, &len,
MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_CONTEXT_SPECIFIC)) !=
@ -1181,11 +1176,6 @@ static int x509_get_other_name(const mbedtls_x509_buf *subject_alt_name,
other_name->value.hardware_module_name.oid.p = p;
other_name->value.hardware_module_name.oid.len = len;
if (p + len >= end) {
mbedtls_platform_zeroize(other_name, sizeof(*other_name));
return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
}
p += len;
if ((ret = mbedtls_asn1_get_tag(&p, end, &len,
MBEDTLS_ASN1_OCTET_STRING)) != 0) {
@ -1197,8 +1187,6 @@ static int x509_get_other_name(const mbedtls_x509_buf *subject_alt_name,
other_name->value.hardware_module_name.val.len = len;
p += len;
if (p != end) {
mbedtls_platform_zeroize(other_name,
sizeof(*other_name));
return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
}