aboutsummaryrefslogtreecommitdiffstats
path: root/src/tls
diff options
context:
space:
mode:
authorJouni Malinen <j@w1.fi>2015-11-29 19:53:23 (GMT)
committerJouni Malinen <j@w1.fi>2015-11-29 19:53:23 (GMT)
commit1adf262144ffae33d85bde6eddcb925f0c84e797 (patch)
tree9f6ba13c42fabc30764dc9f415a2c85b8fcd5c4b /src/tls
parent404597e630013cebed5f2c3dc4c915de90af1840 (diff)
downloadhostap-1adf262144ffae33d85bde6eddcb925f0c84e797.zip
hostap-1adf262144ffae33d85bde6eddcb925f0c84e797.tar.gz
hostap-1adf262144ffae33d85bde6eddcb925f0c84e797.tar.bz2
TLS: Add support for extKeyUsage X.509v3 extension
If the server/client certificate includes the extKeyUsage extension, verify that the listed key purposes include either the anyExtendedKeyUsage wildcard or id-kp-serverAuth/id-kp-clientAuth, respectively. Signed-off-by: Jouni Malinen <j@w1.fi>
Diffstat (limited to 'src/tls')
-rw-r--r--src/tls/tlsv1_client_read.c13
-rw-r--r--src/tls/tlsv1_server_read.c9
-rw-r--r--src/tls/x509v3.c106
-rw-r--r--src/tls/x509v3.h7
4 files changed, 134 insertions, 1 deletions
diff --git a/src/tls/tlsv1_client_read.c b/src/tls/tlsv1_client_read.c
index 5830e7a..40c6a46 100644
--- a/src/tls/tlsv1_client_read.c
+++ b/src/tls/tlsv1_client_read.c
@@ -548,6 +548,19 @@ static int tls_process_certificate(struct tlsv1_client *conn, u8 ct,
return -1;
}
+ if (conn->cred && !conn->cred->server_cert_only && chain &&
+ (chain->extensions_present & X509_EXT_EXT_KEY_USAGE) &&
+ !(chain->ext_key_usage &
+ (X509_EXT_KEY_USAGE_ANY | X509_EXT_KEY_USAGE_SERVER_AUTH))) {
+ tls_cert_chain_failure_event(
+ conn, 0, chain, TLS_FAIL_BAD_CERTIFICATE,
+ "certificate not allowed for server authentication");
+ tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
+ TLS_ALERT_BAD_CERTIFICATE);
+ x509_certificate_chain_free(chain);
+ return -1;
+ }
+
x509_certificate_chain_free(chain);
*in_len = end - in_data;
diff --git a/src/tls/tlsv1_server_read.c b/src/tls/tlsv1_server_read.c
index 0f237ba..8347d7a 100644
--- a/src/tls/tlsv1_server_read.c
+++ b/src/tls/tlsv1_server_read.c
@@ -471,6 +471,15 @@ static int tls_process_certificate(struct tlsv1_server *conn, u8 ct,
return -1;
}
+ if (chain && (chain->extensions_present & X509_EXT_EXT_KEY_USAGE) &&
+ !(chain->ext_key_usage &
+ (X509_EXT_KEY_USAGE_ANY | X509_EXT_KEY_USAGE_CLIENT_AUTH))) {
+ tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
+ TLS_ALERT_BAD_CERTIFICATE);
+ x509_certificate_chain_free(chain);
+ return -1;
+ }
+
x509_certificate_chain_free(chain);
*in_len = end - in_data;
diff --git a/src/tls/x509v3.c b/src/tls/x509v3.c
index 38b49e2..75e3285 100644
--- a/src/tls/x509v3.c
+++ b/src/tls/x509v3.c
@@ -720,6 +720,15 @@ static int x509_id_ce_oid(struct asn1_oid *oid)
}
+static int x509_any_ext_key_usage_oid(struct asn1_oid *oid)
+{
+ return oid->len == 6 &&
+ x509_id_ce_oid(oid) &&
+ oid->oid[3] == 37 /* extKeyUsage */ &&
+ oid->oid[4] == 0 /* anyExtendedKeyUsage */;
+}
+
+
static int x509_parse_ext_key_usage(struct x509_certificate *cert,
const u8 *pos, size_t len)
{
@@ -1073,6 +1082,100 @@ static int x509_parse_ext_issuer_alt_name(struct x509_certificate *cert,
}
+static int x509_id_pkix_oid(struct asn1_oid *oid)
+{
+ return oid->len >= 7 &&
+ oid->oid[0] == 1 /* iso */ &&
+ oid->oid[1] == 3 /* identified-organization */ &&
+ oid->oid[2] == 6 /* dod */ &&
+ oid->oid[3] == 1 /* internet */ &&
+ oid->oid[4] == 5 /* security */ &&
+ oid->oid[5] == 5 /* mechanisms */ &&
+ oid->oid[6] == 7 /* id-pkix */;
+}
+
+
+static int x509_id_kp_oid(struct asn1_oid *oid)
+{
+ /* id-kp */
+ return oid->len >= 8 &&
+ x509_id_pkix_oid(oid) &&
+ oid->oid[7] == 3 /* id-kp */;
+}
+
+
+static int x509_id_kp_server_auth_oid(struct asn1_oid *oid)
+{
+ /* id-kp */
+ return oid->len == 9 &&
+ x509_id_kp_oid(oid) &&
+ oid->oid[8] == 1 /* id-kp-serverAuth */;
+}
+
+
+static int x509_id_kp_client_auth_oid(struct asn1_oid *oid)
+{
+ /* id-kp */
+ return oid->len == 9 &&
+ x509_id_kp_oid(oid) &&
+ oid->oid[8] == 2 /* id-kp-clientAuth */;
+}
+
+
+static int x509_parse_ext_ext_key_usage(struct x509_certificate *cert,
+ const u8 *pos, size_t len)
+{
+ struct asn1_hdr hdr;
+ const u8 *end;
+ struct asn1_oid oid;
+
+ /*
+ * ExtKeyUsageSyntax ::= SEQUENCE SIZE (1..MAX) OF KeyPurposeId
+ *
+ * KeyPurposeId ::= OBJECT IDENTIFIER
+ */
+
+ if (asn1_get_next(pos, len, &hdr) < 0 ||
+ hdr.class != ASN1_CLASS_UNIVERSAL ||
+ hdr.tag != ASN1_TAG_SEQUENCE) {
+ wpa_printf(MSG_DEBUG, "X509: Expected SEQUENCE "
+ "(ExtKeyUsageSyntax) - found class %d tag 0x%x",
+ hdr.class, hdr.tag);
+ return -1;
+ }
+ if (hdr.length > pos + len - hdr.payload)
+ return -1;
+ pos = hdr.payload;
+ end = pos + hdr.length;
+
+ wpa_hexdump(MSG_MSGDUMP, "X509: ExtKeyUsageSyntax", pos, end - pos);
+
+ while (pos < end) {
+ char buf[80];
+
+ if (asn1_get_oid(pos, end - pos, &oid, &pos))
+ return -1;
+ if (x509_any_ext_key_usage_oid(&oid)) {
+ os_strlcpy(buf, "anyExtendedKeyUsage", sizeof(buf));
+ cert->ext_key_usage |= X509_EXT_KEY_USAGE_ANY;
+ } else if (x509_id_kp_server_auth_oid(&oid)) {
+ os_strlcpy(buf, "id-kp-serverAuth", sizeof(buf));
+ cert->ext_key_usage |= X509_EXT_KEY_USAGE_SERVER_AUTH;
+ } else if (x509_id_kp_client_auth_oid(&oid)) {
+ os_strlcpy(buf, "id-kp-clientAuth", sizeof(buf));
+ cert->ext_key_usage |= X509_EXT_KEY_USAGE_CLIENT_AUTH;
+ } else {
+ asn1_oid_to_str(&oid, buf, sizeof(buf));
+ }
+ wpa_printf(MSG_DEBUG, "ExtKeyUsage KeyPurposeId: %s", buf);
+ }
+
+ cert->extensions_present |= X509_EXT_EXT_KEY_USAGE;
+
+ return 0;
+}
+
+
static int x509_parse_extension_data(struct x509_certificate *cert,
struct asn1_oid *oid,
const u8 *pos, size_t len)
@@ -1084,7 +1187,6 @@ static int x509_parse_extension_data(struct x509_certificate *cert,
* certificate policies (section 4.2.1.5)
* name constraints (section 4.2.1.11)
* policy constraints (section 4.2.1.12)
- * extended key usage (section 4.2.1.13)
* inhibit any-policy (section 4.2.1.15)
*/
switch (oid->oid[3]) {
@@ -1096,6 +1198,8 @@ static int x509_parse_extension_data(struct x509_certificate *cert,
return x509_parse_ext_issuer_alt_name(cert, pos, len);
case 19: /* id-ce-basicConstraints */
return x509_parse_ext_basic_constraints(cert, pos, len);
+ case 37: /* id-ce-extKeyUsage */
+ return x509_parse_ext_ext_key_usage(cert, pos, len);
default:
return 1;
}
diff --git a/src/tls/x509v3.h b/src/tls/x509v3.h
index 91a35ba..12ef86e 100644
--- a/src/tls/x509v3.h
+++ b/src/tls/x509v3.h
@@ -68,6 +68,7 @@ struct x509_certificate {
#define X509_EXT_KEY_USAGE (1 << 2)
#define X509_EXT_SUBJECT_ALT_NAME (1 << 3)
#define X509_EXT_ISSUER_ALT_NAME (1 << 4)
+#define X509_EXT_EXT_KEY_USAGE (1 << 5)
/* BasicConstraints */
int ca; /* cA */
@@ -85,6 +86,12 @@ struct x509_certificate {
#define X509_KEY_USAGE_ENCIPHER_ONLY (1 << 7)
#define X509_KEY_USAGE_DECIPHER_ONLY (1 << 8)
+ /* ExtKeyUsage */
+ unsigned long ext_key_usage;
+#define X509_EXT_KEY_USAGE_ANY (1 << 0)
+#define X509_EXT_KEY_USAGE_SERVER_AUTH (1 << 1)
+#define X509_EXT_KEY_USAGE_CLIENT_AUTH (1 << 2)
+
/*
* The DER format certificate follows struct x509_certificate. These
* pointers point to that buffer.