diff options
| -rw-r--r-- | networking/tls.c | 82 |
1 files changed, 45 insertions, 37 deletions
diff --git a/networking/tls.c b/networking/tls.c index 79afe58..71e5ac3 100644 --- a/networking/tls.c +++ b/networking/tls.c @@ -269,6 +269,23 @@ static int xread_tls_block(tls_state_t *tls) return target; } +static int xread_tls_handshake_block(tls_state_t *tls, int min_len) +{ + struct record_hdr *xhdr; + int len = xread_tls_block(tls); + + xhdr = (void*)tls->inbuf; + if (len < min_len + || xhdr->type != RECORD_TYPE_HANDSHAKE + || xhdr->proto_maj != TLS_MAJ + || xhdr->proto_min != TLS_MIN + ) { + tls_error_die(tls); + } + dbg("got HANDSHAKE\n"); + return len; +} + static void send_client_hello(tls_state_t *tls) { struct client_hello { @@ -296,8 +313,8 @@ static void send_client_hello(tls_state_t *tls) //hello.len24_hi = 0; //zero: hello.len24_mid = (sizeof(hello) - sizeof(hello.xhdr) - 4) >> 8; hello.len24_lo = (sizeof(hello) - sizeof(hello.xhdr) - 4); - hello.proto_maj = TLS_MAJ; - hello.proto_min = TLS_MIN; + hello.proto_maj = TLS_MAJ; /* the "requested" version of the protocol, */ + hello.proto_min = TLS_MIN; /* can be higher than one in record headers */ tls_get_random(hello.rand32, sizeof(hello.rand32)); //hello.session_id_len = 0; //hello.cipherid_len16_hi = 0; @@ -325,20 +342,10 @@ static void get_server_hello_or_die(tls_state_t *tls) /* extensions may follow, but only those which client offered in its Hello */ }; struct server_hello *hp; - int len; - len = xread_tls_block(tls); + xread_tls_handshake_block(tls, 74); hp = (void*)tls->inbuf; - if (len != 74 /* TODO: if we accept extensions, should be < instead of != */ - || hp->xhdr.type != RECORD_TYPE_HANDSHAKE - || hp->xhdr.proto_maj != TLS_MAJ - || hp->xhdr.proto_min != TLS_MIN - ) { - /* example: RECORD_TYPE_ALERT if server can't support our ciphers */ - tls_error_die(tls); - } - dbg("got HANDSHAKE\n"); // 74 bytes: // 02 000046 03|03 58|78|cf|c1 50|a5|49|ee|7e|29|48|71|fe|97|fa|e8|2d|19|87|72|90|84|9d|37|a3|f0|cb|6f|5f|e3|3c|2f |20 |d8|1a|78|96|52|d6|91|01|24|b3|d6|5b|b7|d0|6c|b3|e1|78|4e|3c|95|de|74|a0|ba|eb|a7|3a|ff|bd|a2|bf |00|9c |00| //SvHl len=70 maj.min unixtime^^^ 28randbytes^^^^^^^^^^^^^^^^^^^^^^^^^^^^_^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^_^^^ slen sid32bytes^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ cipSel comprSel @@ -572,16 +579,9 @@ static void get_server_cert_or_die(tls_state_t *tls) uint8_t *certbuf; int len, len1; - len = xread_tls_block(tls); + len = xread_tls_handshake_block(tls, 10); + xhdr = (void*)tls->inbuf; - if (len < sizeof(*xhdr) + 10 - || xhdr->type != RECORD_TYPE_HANDSHAKE - || xhdr->proto_maj != TLS_MAJ - || xhdr->proto_min != TLS_MIN - ) { - tls_error_die(tls); - } - dbg("got HANDSHAKE\n"); certbuf = (void*)(xhdr + 1); if (certbuf[0] != HANDSHAKE_CERTIFICATE) tls_error_die(tls); @@ -703,6 +703,15 @@ static void send_client_key_exchange(tls_state_t *tls) xwrite(tls->fd, &record, sizeof(record)); } +static void send_change_cipher_spec(tls_state_t *tls) +{ + static const uint8_t rec[] = { + RECORD_TYPE_CHANGE_CIPHER_SPEC, TLS_MAJ, TLS_MIN, 00, 01, + 01 + }; + xwrite(tls->fd, rec, sizeof(rec)); +} + static void tls_handshake(tls_state_t *tls) { // Client RFC 5246 Server @@ -754,29 +763,28 @@ static void tls_handshake(tls_state_t *tls) // (for example, kernel.org does not even accept DH_anon cipher id) get_server_cert_or_die(tls); - len = xread_tls_block(tls); - /* Next handshake type is not predetermined */ - switch (tls->inbuf[5]) { - case HANDSHAKE_SERVER_KEY_EXCHANGE: + len = xread_tls_handshake_block(tls, 4); + if (tls->inbuf[5] == HANDSHAKE_SERVER_KEY_EXCHANGE) { // 459 bytes: // 0c 00|01|c7 03|00|17|41|04|87|94|2e|2f|68|d0|c9|f4|97|a8|2d|ef|ed|67|ea|c6|f3|b3|56|47|5d|27|b6|bd|ee|70|25|30|5e|b0|8e|f6|21|5a... //SvKey len=455^ // with TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA: 461 bytes: // 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("got SERVER_KEY_EXCHANGE\n"); - len = xread_tls_block(tls); - break; - case HANDSHAKE_CERTIFICATE_REQUEST: - dbg("got CERTIFICATE_REQUEST\n"); - len = xread_tls_block(tls); - break; - case HANDSHAKE_SERVER_HELLO_DONE: + dbg("got SERVER_KEY_EXCHANGE len:%u\n", len); +//need to save it + xread_tls_handshake_block(tls, 4); + } +// if (tls->inbuf[5] == HANDSHAKE_CERTIFICATE_REQUEST) { +// dbg("got CERTIFICATE_REQUEST\n"); +// xread_tls_handshake_block(tls, 4); +// } + if (tls->inbuf[5] == HANDSHAKE_SERVER_HELLO_DONE) { // 0e 000000 (len:0) dbg("got SERVER_HELLO_DONE\n"); send_client_key_exchange(tls); - len = xread_tls_block(tls); - break; - default: + send_change_cipher_spec(tls); +//we now should be able to send encrypted... as soon as we grok AES. + } else { tls_error_die(tls); } } |