- Improved X509 certificate parsing to include extended certificate fields, such as Key Usage
diff --git a/include/polarssl/x509.h b/include/polarssl/x509.h
index c54fc2d..6f0fe02 100644
--- a/include/polarssl/x509.h
+++ b/include/polarssl/x509.h
@@ -144,13 +144,132 @@
#define X509_ISSUER 0x01
#define X509_SUBJECT 0x02
+/** Returns the size of the binary string, without the trailing \0 */
+#define OID_SIZE(x) (sizeof(x) - 1)
+
#define OID_X520 "\x55\x04"
-#define OID_CN "\x55\x04\x03"
+#define OID_CN OID_X520 "\x03"
+
#define OID_PKCS1 "\x2A\x86\x48\x86\xF7\x0D\x01\x01"
-#define OID_PKCS1_RSA "\x2A\x86\x48\x86\xF7\x0D\x01\x01\x01"
-#define OID_PKCS1_RSA_SHA "\x2A\x86\x48\x86\xF7\x0D\x01\x01\x05"
+#define OID_PKCS1_RSA OID_PKCS1 "\x01"
+#define OID_PKCS1_RSA_SHA OID_PKCS1 "\x05"
+
#define OID_PKCS9 "\x2A\x86\x48\x86\xF7\x0D\x01\x09"
-#define OID_PKCS9_EMAIL "\x2A\x86\x48\x86\xF7\x0D\x01\x09\x01"
+#define OID_PKCS9_EMAIL OID_PKCS9 "\x01"
+
+/** ISO arc for standard certificate and CRL extensions */
+#define OID_ID_CE "\x55\x1D" /**< id-ce OBJECT IDENTIFIER ::= {joint-iso-ccitt(2) ds(5) 29} */
+
+/**
+ * Private Internet Extensions
+ * { iso(1) identified-organization(3) dod(6) internet(1)
+ * security(5) mechanisms(5) pkix(7) }
+ */
+#define OID_PKIX "\x2B\x06\x01\x05\x05\x07"
+
+/*
+ * OIDs for standard certificate extensions
+ */
+#define OID_AUTHORITY_KEY_IDENTIFIER OID_ID_CE "\x23" /**< id-ce-authorityKeyIdentifier OBJECT IDENTIFIER ::= { id-ce 35 } */
+#define OID_SUBJECT_KEY_IDENTIFIER OID_ID_CE "\x0E" /**< id-ce-subjectKeyIdentifier OBJECT IDENTIFIER ::= { id-ce 14 } */
+#define OID_KEY_USAGE OID_ID_CE "\x0F" /**< id-ce-keyUsage OBJECT IDENTIFIER ::= { id-ce 15 } */
+#define OID_CERTIFICATE_POLICIES OID_ID_CE "\x20" /**< id-ce-certificatePolicies OBJECT IDENTIFIER ::= { id-ce 32 } */
+#define OID_POLICY_MAPPINGS OID_ID_CE "\x21" /**< id-ce-policyMappings OBJECT IDENTIFIER ::= { id-ce 33 } */
+#define OID_SUBJECT_ALT_NAME OID_ID_CE "\x11" /**< id-ce-subjectAltName OBJECT IDENTIFIER ::= { id-ce 17 } */
+#define OID_ISSUER_ALT_NAME OID_ID_CE "\x12" /**< id-ce-issuerAltName OBJECT IDENTIFIER ::= { id-ce 18 } */
+#define OID_SUBJECT_DIRECTORY_ATTRS OID_ID_CE "\x09" /**< id-ce-subjectDirectoryAttributes OBJECT IDENTIFIER ::= { id-ce 9 } */
+#define OID_BASIC_CONSTRAINTS OID_ID_CE "\x13" /**< id-ce-basicConstraints OBJECT IDENTIFIER ::= { id-ce 19 } */
+#define OID_NAME_CONSTRAINTS OID_ID_CE "\x1E" /**< id-ce-nameConstraints OBJECT IDENTIFIER ::= { id-ce 30 } */
+#define OID_POLICY_CONSTRAINTS OID_ID_CE "\x24" /**< id-ce-policyConstraints OBJECT IDENTIFIER ::= { id-ce 36 } */
+#define OID_EXTENDED_KEY_USAGE OID_ID_CE "\x25" /**< id-ce-extKeyUsage OBJECT IDENTIFIER ::= { id-ce 37 } */
+#define OID_CRL_DISTRIBUTION_POINTS OID_ID_CE "\x1F" /**< id-ce-cRLDistributionPoints OBJECT IDENTIFIER ::= { id-ce 31 } */
+#define OID_INIHIBIT_ANYPOLICY OID_ID_CE "\x36" /**< id-ce-inhibitAnyPolicy OBJECT IDENTIFIER ::= { id-ce 54 } */
+#define OID_FRESHEST_CRL OID_ID_CE "\x2E" /**< id-ce-freshestCRL OBJECT IDENTIFIER ::= { id-ce 46 } */
+
+/*
+ * X.509 v3 Key Usage Extension flags
+ */
+#define KU_DIGITAL_SIGNATURE (0x80) /* bit 0 */
+#define KU_NON_REPUDIATION (0x40) /* bit 1 */
+#define KU_KEY_ENCIPHERMENT (0x20) /* bit 2 */
+#define KU_DATA_ENCIPHERMENT (0x10) /* bit 3 */
+#define KU_KEY_AGREEMENT (0x08) /* bit 4 */
+#define KU_KEY_CERT_SIGN (0x04) /* bit 5 */
+#define KU_CRL_SIGN (0x02) /* bit 6 */
+
+/*
+ * X.509 v3 Extended key usage OIDs
+ */
+#define OID_ANY_EXTENDED_KEY_USAGE OID_EXTENDED_KEY_USAGE "\x00" /**< anyExtendedKeyUsage OBJECT IDENTIFIER ::= { id-ce-extKeyUsage 0 } */
+
+#define OID_KP OID_PKIX "\x03" /**< id-kp OBJECT IDENTIFIER ::= { id-pkix 3 } */
+#define OID_SERVER_AUTH OID_KP "\x01" /**< id-kp-serverAuth OBJECT IDENTIFIER ::= { id-kp 1 } */
+#define OID_CLIENT_AUTH OID_KP "\x02" /**< id-kp-clientAuth OBJECT IDENTIFIER ::= { id-kp 2 } */
+#define OID_CODE_SIGNING OID_KP "\x03" /**< id-kp-codeSigning OBJECT IDENTIFIER ::= { id-kp 3 } */
+#define OID_EMAIL_PROTECTION OID_KP "\x04" /**< id-kp-emailProtection OBJECT IDENTIFIER ::= { id-kp 4 } */
+#define OID_TIME_STAMPING OID_KP "\x08" /**< id-kp-timeStamping OBJECT IDENTIFIER ::= { id-kp 8 } */
+#define OID_OCSP_SIGNING OID_KP "\x09" /**< id-kp-OCSPSigning OBJECT IDENTIFIER ::= { id-kp 9 } */
+
+#define STRING_SERVER_AUTH "TLS Web Server Authentication"
+#define STRING_CLIENT_AUTH "TLS Web Client Authentication"
+#define STRING_CODE_SIGNING "Code Signing"
+#define STRING_EMAIL_PROTECTION "E-mail Protection"
+#define STRING_TIME_STAMPING "Time Stamping"
+#define STRING_OCSP_SIGNING "OCSP Signing"
+
+/*
+ * OIDs for CRL extensions
+ */
+#define OID_PRIVATE_KEY_USAGE_PERIOD OID_ID_CE "\x10"
+#define OID_CRL_NUMBER OID_ID_CE "\x14" /**< id-ce-cRLNumber OBJECT IDENTIFIER ::= { id-ce 20 } */
+
+/*
+ * Netscape certificate extensions
+ */
+#define OID_NETSCAPE "\x60\x86\x48\x01\x86\xF8\x42" /**< Netscape OID */
+#define OID_NS_CERT OID_NETSCAPE "\x01"
+#define OID_NS_CERT_TYPE OID_NS_CERT "\x01"
+#define OID_NS_BASE_URL OID_NS_CERT "\x02"
+#define OID_NS_REVOCATION_URL OID_NS_CERT "\x03"
+#define OID_NS_CA_REVOCATION_URL OID_NS_CERT "\x04"
+#define OID_NS_RENEWAL_URL OID_NS_CERT "\x07"
+#define OID_NS_CA_POLICY_URL OID_NS_CERT "\x08"
+#define OID_NS_SSL_SERVER_NAME OID_NS_CERT "\x0C"
+#define OID_NS_COMMENT OID_NS_CERT "\x0D"
+#define OID_NS_DATA_TYPE OID_NETSCAPE "\x02"
+#define OID_NS_CERT_SEQUENCE OID_NS_DATA_TYPE "\x05"
+
+/*
+ * Netscape certificate types
+ * (http://www.mozilla.org/projects/security/pki/nss/tech-notes/tn3.html)
+ */
+
+#define NS_CERT_TYPE_SSL_CLIENT (0x80) /* bit 0 */
+#define NS_CERT_TYPE_SSL_SERVER (0x40) /* bit 1 */
+#define NS_CERT_TYPE_EMAIL (0x20) /* bit 2 */
+#define NS_CERT_TYPE_OBJECT_SIGNING (0x10) /* bit 3 */
+#define NS_CERT_TYPE_RESERVED (0x08) /* bit 4 */
+#define NS_CERT_TYPE_SSL_CA (0x04) /* bit 5 */
+#define NS_CERT_TYPE_EMAIL_CA (0x02) /* bit 6 */
+#define NS_CERT_TYPE_OBJECT_SIGNING_CA (0x01) /* bit 7 */
+
+#define EXT_AUTHORITY_KEY_IDENTIFIER (1 << 0)
+#define EXT_SUBJECT_KEY_IDENTIFIER (1 << 1)
+#define EXT_KEY_USAGE (1 << 2)
+#define EXT_CERTIFICATE_POLICIES (1 << 3)
+#define EXT_POLICY_MAPPINGS (1 << 4)
+#define EXT_SUBJECT_ALT_NAME (1 << 5)
+#define EXT_ISSUER_ALT_NAME (1 << 6)
+#define EXT_SUBJECT_DIRECTORY_ATTRS (1 << 7)
+#define EXT_BASIC_CONSTRAINTS (1 << 8)
+#define EXT_NAME_CONSTRAINTS (1 << 9)
+#define EXT_POLICY_CONSTRAINTS (1 << 10)
+#define EXT_EXTENDED_KEY_USAGE (1 << 11)
+#define EXT_CRL_DISTRIBUTION_POINTS (1 << 12)
+#define EXT_INIHIBIT_ANYPOLICY (1 << 13)
+#define EXT_FRESHEST_CRL (1 << 14)
+
+#define EXT_NS_CERT_TYPE (1 << 16)
/**
* @addtogroup x509_module
@@ -173,6 +292,17 @@
x509_buf;
/**
+ * Container for ASN1 bit strings.
+ */
+typedef struct _x509_bitstring
+{
+ int len; /**< ASN1 length, e.g. in octets. */
+ unsigned char unused_bits; /**< Number of unused bits at the end of the string */
+ unsigned char *p; /**< Raw ASN1 data for the bit string */
+}
+x509_bitstring;
+
+/**
* Container for ASN1 named information objects.
* It allows for Relative Distinguished Names (e.g. cn=polarssl,ou=code,etc.).
*/
@@ -184,6 +314,16 @@
}
x509_name;
+/**
+ * Container for a sequence of ASN.1 items
+ */
+typedef struct _x509_sequence
+{
+ x509_buf buf; /**< Buffer containing the given ASN.1 item. */
+ struct _x509_sequence *next; /**< The next entry in the sequence. */
+}
+x509_sequence;
+
/** Container for date and time (precision in seconds). */
typedef struct _x509_time
{
@@ -220,9 +360,16 @@
x509_buf subject_id; /**< Optional X.509 v2/v3 subject unique identifier. */
x509_buf v3_ext; /**< Optional X.509 v3 extensions. Only Basic Contraints are supported at this time. */
+ int ext_types; /**< Bit string containing detected and parsed extensions */
int ca_istrue; /**< Optional Basic Constraint extension value: 1 if this certificate belongs to a CA, 0 otherwise. */
int max_pathlen; /**< Optional Basic Constraint extension value: The maximum path length to the root certificate. */
+ unsigned char key_usage; /**< Optional key usage extension value: See the values below */
+
+ x509_sequence ext_key_usage; /**< Optional list of extended key usage OIDs. */
+
+ unsigned char ns_cert_type; /**< Optional Netscape certificate type extension value: See the values below */
+
x509_buf sig_oid2; /**< Signature algorithm. Must match sig_oid1. */
x509_buf sig; /**< Signature: hash of the tbs part signed with the private key. */
int sig_alg; /**< Internal representation of the signature algorithm, e.g. SIG_RSA_MD2 */
@@ -477,6 +624,28 @@
const x509_crl *crl );
/**
+ * \brief Give an known OID, return its descriptive string.
+ *
+ * \param oid buffer containing the oid
+ *
+ * \return Return a string if the OID is known,
+ * or NULL otherwise.
+ */
+const char *x509_oid_get_description( x509_buf *oid );
+
+/*
+ * \brief Give an OID, return a string version of its OID number.
+ *
+ * \param buf Buffer to write to
+ * \param size Maximum size of buffer
+ * \param oid Buffer containing the OID
+ *
+ * \return The amount of data written to the buffer, or -1 in
+ * case of an error.
+ */
+int x509_oid_get_numeric_string( char *buf, size_t size, x509_buf *oid );
+
+/**
* \brief Check a given x509_time against the system time and check
* if it is valid.
*
@@ -521,6 +690,17 @@
int (*f_vrfy)(void *, x509_cert *, int, int),
void *p_vrfy );
+/**
+ * \brief Verify the certificate signature
+ *
+ * \param crt a certificate to be verified
+ * \param crl the CRL to verify against
+ *
+ * \return 1 if the certificate is revoked, 0 otherwise
+ *
+ */
+int x509parse_revoked( const x509_cert *crt, const x509_crl *crl );
+
/** @} name Functions to verify a certificate */