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| author | Demi Marie Obenour <demiobenour@gmail.com> | 2022-12-08 15:23:56 -0500 |
|---|---|---|
| committer | Demi Marie Obenour <demiobenour@gmail.com> | 2022-12-29 18:41:10 -0500 |
| commit | fd37982a19a4a2911912ce321b9468993a0919ad (patch) | |
| tree | c3cb872e213db78fe830451c90641bf06adc977c | |
| parent | e9e4a2a6fd33d8fc21b00cfc9816a3dd3fef47fe (diff) | |
| download | trusted-firmware-a-fd37982a19a4a291.tar.gz | |
fix(auth): forbid junk after extensions
The extensions must use all remaining bytes in the TBSCertificate.
Change-Id: Idf48f7168e146d050ba62dbc732638946fcd6c92
Signed-off-by: Demi Marie Obenour <demiobenour@gmail.com>
| -rw-r--r-- | drivers/auth/mbedtls/mbedtls_x509_parser.c | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/drivers/auth/mbedtls/mbedtls_x509_parser.c b/drivers/auth/mbedtls/mbedtls_x509_parser.c index 49bc008ed1..8c78003bb2 100644 --- a/drivers/auth/mbedtls/mbedtls_x509_parser.c +++ b/drivers/auth/mbedtls/mbedtls_x509_parser.c @@ -304,24 +304,26 @@ static int cert_parse(void *img, unsigned int img_len) /* * extensions [3] EXPLICIT Extensions OPTIONAL + * -- must use all remaining bytes in TBSCertificate */ ret = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | 3); - if (ret != 0) { + if ((ret != 0) || (len != (size_t)(end - p))) { return IMG_PARSER_ERR_FORMAT; } /* * Extensions ::= SEQUENCE SIZE (1..MAX) OF Extension + * -- must use all remaining bytes in TBSCertificate */ v3_ext.p = p; ret = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE); - if (ret != 0) { + if ((ret != 0) || (len != (size_t)(end - p))) { return IMG_PARSER_ERR_FORMAT; } - v3_ext.len = (p + len) - v3_ext.p; + v3_ext.len = end - v3_ext.p; /* * Check extensions integrity |