tls: if got CERTIFICATE_REQUEST, send an empty CERTIFICATE
wolfssl test server is not satisfied by an empty one,
but some real servers might be.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/networking/tls.c b/networking/tls.c
index a65da4a..dc94a8b 100644
--- a/networking/tls.c
+++ b/networking/tls.c
@@ -484,21 +484,24 @@
static void bad_record_die(tls_state_t *tls, const char *expected, int len)
{
- bb_error_msg_and_die("got bad TLS record (len:%d) while expecting %s", len, expected);
+ bb_error_msg("got bad TLS record (len:%d) while expecting %s", len, expected);
if (len > 0) {
uint8_t *p = tls->inbuf;
- while (len > 0)
+ while (len > 0) {
fprintf(stderr, " %02x", *p++);
+ len--;
+ }
fputc('\n', stderr);
}
xfunc_die();
}
-static void tls_error_die(tls_state_t *tls)
+static void tls_error_die(tls_state_t *tls, int line)
{
dump_tls_record(tls->inbuf, tls->ofs_to_buffered + tls->buffered_size);
- bb_error_msg_and_die("TODO: useful diagnostic about %p", tls);
+ bb_error_msg_and_die("tls error at line %d cipher:%04x", line, tls->cipher_id);
}
+#define tls_error_die(tls) tls_error_die(tls, __LINE__)
#if 0 //UNUSED
static void tls_free_inbuf(tls_state_t *tls)
@@ -1343,6 +1346,26 @@
find_key_in_der_cert(tls, certbuf + 10, len);
}
+static void send_empty_client_cert(tls_state_t *tls)
+{
+ struct client_empty_cert {
+ uint8_t type;
+ uint8_t len24_hi, len24_mid, len24_lo;
+ uint8_t cert_chain_len24_hi, cert_chain_len24_mid, cert_chain_len24_lo;
+ };
+ struct client_empty_cert *record;
+
+ record = tls_get_outbuf(tls, sizeof(*record));
+//FIXME: can just memcpy a ready-made one.
+ fill_handshake_record_hdr(record, HANDSHAKE_CERTIFICATE, sizeof(*record));
+ record->cert_chain_len24_hi = 0;
+ record->cert_chain_len24_mid = 0;
+ record->cert_chain_len24_lo = 0;
+
+ dbg(">> CERTIFICATE\n");
+ xwrite_and_update_handshake_hash(tls, sizeof(*record));
+}
+
static void send_client_key_exchange(tls_state_t *tls)
{
struct client_key_exchange {
@@ -1584,23 +1607,25 @@
// 0c 00|01|c9 03|00|17|41|04|cd|9b|b4|29|1f|f6|b0|c2|84|82|7f|29|6a|47|4e|ec|87|0b|c1|9c|69|e1|f8|c6|d0|53|e9|27|90|a5|c8|02|15|75...
dbg("<< SERVER_KEY_EXCHANGE len:%u\n", len);
//probably need to save it
- tls_xread_handshake_block(tls, 4);
+ len = tls_xread_handshake_block(tls, 4);
}
-// if (tls->inbuf[RECHDR_LEN] == HANDSHAKE_CERTIFICATE_REQUEST) {
-// dbg("<< CERTIFICATE_REQUEST\n");
-// RFC 5246: (in response to this,) "If no suitable certificate is available,
-// the client MUST send a certificate message containing no
-// certificates. That is, the certificate_list structure has a
-// length of zero. ...
-// Client certificates are sent using the Certificate structure
-// defined in Section 7.4.2."
-// (i.e. the same format as server certs)
-// tls_xread_handshake_block(tls, 4);
-// }
+ if (tls->inbuf[RECHDR_LEN] == HANDSHAKE_CERTIFICATE_REQUEST) {
+ dbg("<< CERTIFICATE_REQUEST\n");
+ // RFC 5246: "If no suitable certificate is available,
+ // the client MUST send a certificate message containing no
+ // certificates. That is, the certificate_list structure has a
+ // length of zero. ...
+ // Client certificates are sent using the Certificate structure
+ // defined in Section 7.4.2."
+ // (i.e. the same format as server certs)
+ send_empty_client_cert(tls);
+ len = tls_xread_handshake_block(tls, 4);
+ }
- if (tls->inbuf[RECHDR_LEN] != HANDSHAKE_SERVER_HELLO_DONE)
- tls_error_die(tls);
+ if (tls->inbuf[RECHDR_LEN] != HANDSHAKE_SERVER_HELLO_DONE) {
+ bad_record_die(tls, "'server hello done'", len);
+ }
// 0e 000000 (len:0)
dbg("<< SERVER_HELLO_DONE\n");
@@ -1616,7 +1641,7 @@
/* Get CHANGE_CIPHER_SPEC */
len = tls_xread_record(tls);
if (len != 1 || memcmp(tls->inbuf, rec_CHANGE_CIPHER_SPEC, 6) != 0)
- tls_error_die(tls);
+ bad_record_die(tls, "switch to encrypted traffic", len);
dbg("<< CHANGE_CIPHER_SPEC\n");
if (tls->cipher_id == TLS_RSA_WITH_NULL_SHA256)
tls->min_encrypted_len_on_read = tls->MAC_size;