int main(int argc, char *argv[])
{
char *buf;
size_t len;
struct x509_certificate *certs = NULL, *last = NULL, *cert;
int i, reason;
wpa_debug_level = 0;
if (argc < 3 || strcmp(argv[1], "-v") != 0) {
printf("usage: test_x509v3 -v <cert1.der> <cert2.der> ..\n");
return -1;
}
for (i = 2; i < argc; i++) {
printf("Reading: %s\n", argv[i]);
buf = os_readfile(argv[i], &len);
if (buf == NULL) {
printf("Failed to read '%s'\n", argv[i]);
return -1;
}
cert = x509_certificate_parse((u8 *) buf, len);
if (cert == NULL) {
printf("Failed to parse X.509 certificate\n");
return -1;
}
free(buf);
if (certs == NULL)
certs = cert;
else
last->next = cert;
last = cert;
}
printf("\n\nValidating certificate chain\n");
if (x509_certificate_chain_validate(last, certs, &reason, 0) < 0) {
printf("\nCertificate chain validation failed: %d\n", reason);
return -1;
}
printf("\nCertificate chain is valid\n");
return 0;
}
/**
* tls_parse_cert - Parse DER encoded X.509 certificate and get public key
* @buf: ASN.1 DER encoded certificate
* @len: Length of the buffer
* @pk: Buffer for returning the allocated public key
* Returns: 0 on success, -1 on failure
*
* This functions parses an ASN.1 DER encoded X.509 certificate and retrieves
* the public key from it. The caller is responsible for freeing the public key
* by calling crypto_public_key_free().
*/
int tls_parse_cert(const u8 *buf, size_t len, struct crypto_public_key **pk)
{
struct x509_certificate *cert;
wpa_hexdump(MSG_MSGDUMP, "TLSv1: Parse ASN.1 DER certificate",
buf, len);
*pk = crypto_public_key_from_cert(buf, len);
if (*pk)
return 0;
cert = x509_certificate_parse(buf, len);
if (cert == NULL) {
wpa_printf(MSG_DEBUG, "TLSv1: Failed to parse X.509 "
"certificate");
return -1;
}
/* TODO
* verify key usage (must allow encryption)
*
* All certificate profiles, key and cryptographic formats are
* defined by the IETF PKIX working group [PKIX]. When a key
* usage extension is present, the digitalSignature bit must be
* set for the key to be eligible for signing, as described
* above, and the keyEncipherment bit must be present to allow
* encryption, as described above. The keyAgreement bit must be
* set on Diffie-Hellman certificates. (PKIX: RFC 3280)
*/
*pk = crypto_public_key_import(cert->public_key, cert->public_key_len);
x509_certificate_free(cert);
if (*pk == NULL) {
wpa_printf(MSG_ERROR, "TLSv1: Failed to import "
"server public key");
return -1;
}
return 0;
}
int main(int argc, char *argv[])
{
FILE *f;
u8 buf[3000];
size_t len;
struct x509_certificate *cert;
wpa_debug_level = 0;
f = fopen(argv[1], "rb");
if (f == NULL)
return -1;
len = fread(buf, 1, sizeof(buf), f);
fclose(f);
cert = x509_certificate_parse(buf, len);
if (cert == NULL)
printf("Failed to parse X.509 certificate\n");
x509_certificate_free(cert);
return 0;
}
static int tls_process_certificate(struct tlsv1_server *conn, u8 ct,
const u8 *in_data, size_t *in_len) {
const u8 *pos, *end;
size_t left, len, list_len, cert_len, idx;
u8 type;
struct x509_certificate *chain = NULL, *last = NULL, *cert;
int reason;
if (ct != TLS_CONTENT_TYPE_HANDSHAKE) {
wpa_printf(MSG_DEBUG, "TLSv1: Expected Handshake; "
"received content type 0x%x", ct);
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_UNEXPECTED_MESSAGE);
return -1;
}
pos = in_data;
left = *in_len;
if (left < 4) {
wpa_printf(MSG_DEBUG, "TLSv1: Too short Certificate message "
"(len=%lu)", (unsigned long) left);
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_DECODE_ERROR);
return -1;
}
type = *pos++;
len = WPA_GET_BE24(pos);
pos += 3;
left -= 4;
if (len > left) {
wpa_printf(MSG_DEBUG, "TLSv1: Unexpected Certificate message "
"length (len=%lu != left=%lu)",
(unsigned long) len, (unsigned long) left);
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_DECODE_ERROR);
return -1;
}
if (type == TLS_HANDSHAKE_TYPE_CLIENT_KEY_EXCHANGE) {
if (conn->verify_peer) {
wpa_printf(MSG_DEBUG, "TLSv1: Client did not include "
"Certificate");
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_UNEXPECTED_MESSAGE);
return -1;
}
return tls_process_client_key_exchange(conn, ct, in_data,
in_len);
}
if (type != TLS_HANDSHAKE_TYPE_CERTIFICATE) {
wpa_printf(MSG_DEBUG, "TLSv1: Received unexpected handshake "
"message %d (expected Certificate/"
"ClientKeyExchange)", type);
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_UNEXPECTED_MESSAGE);
return -1;
}
wpa_printf(MSG_DEBUG,
"TLSv1: Received Certificate (certificate_list len %lu)",
(unsigned long) len);
/*
* opaque ASN.1Cert<2^24-1>;
*
* struct {
* ASN.1Cert certificate_list<1..2^24-1>;
* } Certificate;
*/
end = pos + len;
if (end - pos < 3) {
wpa_printf(MSG_DEBUG, "TLSv1: Too short Certificate "
"(left=%lu)", (unsigned long) left);
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_DECODE_ERROR);
return -1;
}
list_len = WPA_GET_BE24(pos);
pos += 3;
if ((size_t) (end - pos) != list_len) {
wpa_printf(MSG_DEBUG, "TLSv1: Unexpected certificate_list "
"length (len=%lu left=%lu)",
(unsigned long) list_len,
(unsigned long) (end - pos));
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_DECODE_ERROR);
return -1;
}
idx = 0;
while (pos < end) {
if (end - pos < 3) {
wpa_printf(MSG_DEBUG, "TLSv1: Failed to parse "
"certificate_list");
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_DECODE_ERROR);
x509_certificate_chain_free(chain);
return -1;
}
cert_len = WPA_GET_BE24(pos);
pos += 3;
if ((size_t) (end - pos) < cert_len) {
wpa_printf(MSG_DEBUG, "TLSv1: Unexpected certificate "
"length (len=%lu left=%lu)",
(unsigned long) cert_len,
(unsigned long) (end - pos));
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_DECODE_ERROR);
x509_certificate_chain_free(chain);
return -1;
}
wpa_printf(MSG_DEBUG, "TLSv1: Certificate %lu (len %lu)",
(unsigned long) idx, (unsigned long) cert_len);
if (idx == 0) {
crypto_public_key_free(conn->client_rsa_key);
if (tls_parse_cert(pos, cert_len,
&conn->client_rsa_key)) {
wpa_printf(MSG_DEBUG, "TLSv1: Failed to parse "
"the certificate");
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_BAD_CERTIFICATE);
x509_certificate_chain_free(chain);
return -1;
}
}
cert = x509_certificate_parse(pos, cert_len);
if (cert == NULL) {
wpa_printf(MSG_DEBUG, "TLSv1: Failed to parse "
"the certificate");
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_BAD_CERTIFICATE);
x509_certificate_chain_free(chain);
return -1;
}
if (last == NULL)
chain = cert;
else
last->next = cert;
last = cert;
idx++;
pos += cert_len;
}
if (x509_certificate_chain_validate(conn->cred->trusted_certs, chain,
&reason) < 0) {
int tls_reason;
wpa_printf(MSG_DEBUG, "TLSv1: Server certificate chain "
"validation failed (reason=%d)", reason);
switch (reason) {
case X509_VALIDATE_BAD_CERTIFICATE:
tls_reason = TLS_ALERT_BAD_CERTIFICATE;
break;
case X509_VALIDATE_UNSUPPORTED_CERTIFICATE:
tls_reason = TLS_ALERT_UNSUPPORTED_CERTIFICATE;
break;
case X509_VALIDATE_CERTIFICATE_REVOKED:
tls_reason = TLS_ALERT_CERTIFICATE_REVOKED;
break;
case X509_VALIDATE_CERTIFICATE_EXPIRED:
tls_reason = TLS_ALERT_CERTIFICATE_EXPIRED;
break;
case X509_VALIDATE_CERTIFICATE_UNKNOWN:
tls_reason = TLS_ALERT_CERTIFICATE_UNKNOWN;
break;
case X509_VALIDATE_UNKNOWN_CA:
tls_reason = TLS_ALERT_UNKNOWN_CA;
break;
default:
tls_reason = TLS_ALERT_BAD_CERTIFICATE;
break;
}
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, tls_reason);
x509_certificate_chain_free(chain);
return -1;
}
x509_certificate_chain_free(chain);
*in_len = end - in_data;
conn->state = CLIENT_KEY_EXCHANGE;
return 0;
}