diff options
Diffstat (limited to 'lib/minitasn1/decoding.c')
-rw-r--r-- | lib/minitasn1/decoding.c | 106 |
1 files changed, 34 insertions, 72 deletions
diff --git a/lib/minitasn1/decoding.c b/lib/minitasn1/decoding.c index 9cd5a349ff..968fa96bfd 100644 --- a/lib/minitasn1/decoding.c +++ b/lib/minitasn1/decoding.c @@ -45,8 +45,20 @@ _asn1_error_description_tag_error (ASN1_TYPE node, char *ErrorDescription) } -static int -_asn1_get_length_der (const unsigned char *der, int der_len, int *len) +/** + * asn1_get_length_der: + * @der: DER data to decode. + * @der_len: Length of DER data to decode. + * @len: Output variable containing the length of the DER length field. + * + * Extract a length field from DER data. + * + * Returns: Return the decoded length value, or -1 on indefinite + * length, or -2 when the value was too big to fit in a int, or -4 + * when the decoded length value plus @len would exceed @der_len. + **/ +signed long +asn1_get_length_der (const unsigned char *der, int der_len, int *len) { int ans; int k, punt; @@ -71,7 +83,7 @@ _asn1_get_length_der (const unsigned char *der, int der_len, int *len) ans = 0; while (punt <= k && punt < der_len) { - unsigned long last = ans; + int last = ans; ans = ans * 256 + der[punt++]; if (ans < last) @@ -81,61 +93,17 @@ _asn1_get_length_der (const unsigned char *der, int der_len, int *len) } else { /* indefinite length method */ - ans = -1; + *len = punt; + return -1; } *len = punt; + if (ans + *len < ans || ans + *len > der_len) + return -4; return ans; } } -/*- - * asn1_get_length_der_checked: - * @der: DER data to decode. - * @der_len: Length of DER data to decode. - * @len: Output variable containing the length of the DER length field. - * - * Extract a length field from DER data. - * - * Returns: Return the decoded length value, or -1 on indefinite - * length, -2 when the value was too big or -3 when the value - * and the size of length exceed the @der_len. - -*/ -static int -asn1_get_length_der_checked (const unsigned char *der, int der_len, int *len) -{ -int ret, tot; - - ret = _asn1_get_length_der(der, der_len, len); - if (ret < 0) - return ret; - - tot = ret + *len; - - if (tot < ret || tot > der_len) - return -3; - - return ret; -} - -/** - * asn1_get_length_der: - * @der: DER data to decode. - * @der_len: Length of DER data to decode. - * @len: Output variable containing the length of the DER length field. - * - * Extract a length field from DER data. - * - * Returns: Return the decoded length value, or -1 on indefinite - * length, -2 when the value was too big or -3 when the value - * and the size of length exceed the @der_len. - **/ -long -asn1_get_length_der (const unsigned char *der, int der_len, int *len) -{ - return asn1_get_length_der_checked(der, der_len, len); -} - /** * asn1_get_tag_der: * @der: DER data to decode. @@ -193,24 +161,6 @@ asn1_get_tag_der (const unsigned char *der, int der_len, return ASN1_SUCCESS; } -static int -_asn1_get_length_ber (const unsigned char *ber, int ber_len, int *len) -{ - int ret; - long err; - - ret = _asn1_get_length_der (ber, ber_len, len); - if (ret == -1) - { /* indefinite length method */ - ret = ber_len; - err = _asn1_get_indefinite_length_string (ber + 1, &ret); - if (err != ASN1_SUCCESS) - return -3; - } - - return ret; -} - /** * asn1_get_length_ber: * @ber: BER data to decode. @@ -226,10 +176,22 @@ _asn1_get_length_ber (const unsigned char *ber, int ber_len, int *len) * * Since: 2.0 **/ -long +signed long asn1_get_length_ber (const unsigned char *ber, int ber_len, int *len) { - return _asn1_get_length_ber(ber, ber_len, len); + int ret; + long err; + + ret = asn1_get_length_der (ber, ber_len, len); + if (ret == -1) + { /* indefinite length method */ + ret = ber_len; + err = _asn1_get_indefinite_length_string (ber + 1, &ret); + if (err != ASN1_SUCCESS) + return -3; + } + + return ret; } /** @@ -434,7 +396,7 @@ _asn1_extract_tag_der (ASN1_TYPE node, const unsigned char *der, int der_len, counter += len2; len3 = - _asn1_get_length_ber (der + counter, der_len - counter, + asn1_get_length_ber (der + counter, der_len - counter, &len2); if (len3 < 0) return ASN1_DER_ERROR; |