diff options
Diffstat (limited to 'networking/tls.c')
| -rw-r--r-- | networking/tls.c | 362 |
1 files changed, 202 insertions, 160 deletions
diff --git a/networking/tls.c b/networking/tls.c index 71e5ac3..44c9da1 100644 --- a/networking/tls.c +++ b/networking/tls.c @@ -286,85 +286,6 @@ static int xread_tls_handshake_block(tls_state_t *tls, int min_len) return len; } -static void send_client_hello(tls_state_t *tls) -{ - struct client_hello { - struct record_hdr xhdr; - uint8_t type; - uint8_t len24_hi, len24_mid, len24_lo; - uint8_t proto_maj, proto_min; - uint8_t rand32[32]; - uint8_t session_id_len; - /* uint8_t session_id[]; */ - uint8_t cipherid_len16_hi, cipherid_len16_lo; - uint8_t cipherid[2 * 1]; /* actually variable */ - uint8_t comprtypes_len; - uint8_t comprtypes[1]; /* actually variable */ - }; - struct client_hello hello; - - memset(&hello, 0, sizeof(hello)); - hello.xhdr.type = RECORD_TYPE_HANDSHAKE; - hello.xhdr.proto_maj = TLS_MAJ; - hello.xhdr.proto_min = TLS_MIN; - //zero: hello.xhdr.len16_hi = (sizeof(hello) - sizeof(hello.xhdr)) >> 8; - hello.xhdr.len16_lo = (sizeof(hello) - sizeof(hello.xhdr)); - hello.type = HANDSHAKE_CLIENT_HELLO; - //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; /* 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; - hello.cipherid_len16_lo = 2 * 1; - hello.cipherid[0] = CIPHER_ID >> 8; - hello.cipherid[1] = CIPHER_ID & 0xff; - hello.comprtypes_len = 1; - //hello.comprtypes[0] = 0; - - xwrite(tls->fd, &hello, sizeof(hello)); -} - -static void get_server_hello_or_die(tls_state_t *tls) -{ - struct server_hello { - struct record_hdr xhdr; - uint8_t type; - uint8_t len24_hi, len24_mid, len24_lo; - uint8_t proto_maj, proto_min; - uint8_t rand32[32]; /* first 4 bytes are unix time in BE format */ - uint8_t session_id_len; - uint8_t session_id[32]; - uint8_t cipherid_hi, cipherid_lo; - uint8_t comprtype; - /* extensions may follow, but only those which client offered in its Hello */ - }; - struct server_hello *hp; - - xread_tls_handshake_block(tls, 74); - - hp = (void*)tls->inbuf; - // 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 - if (hp->type != HANDSHAKE_SERVER_HELLO - || hp->len24_hi != 0 - || hp->len24_mid != 0 - || hp->len24_lo != 70 - || hp->proto_maj != TLS_MAJ - || hp->proto_min != TLS_MIN - || hp->session_id_len != 32 - || hp->cipherid_hi != (CIPHER_ID >> 8) - || hp->cipherid_lo != (CIPHER_ID & 0xff) - || hp->comprtype != 0 - ) { - tls_error_die(tls); - } - dbg("got SERVER_HELLO\n"); -} - static unsigned get_der_len(uint8_t **bodyp, uint8_t *der, uint8_t *end) { unsigned len, len1; @@ -573,7 +494,104 @@ static void find_key_in_der_cert(tls_state_t *tls, uint8_t *der, int len) dbg("server_rsa_pub_key.size:%d\n", tls->server_rsa_pub_key.size); } -static void get_server_cert_or_die(tls_state_t *tls) +/* + * TLS Handshake routines + */ +static void send_client_hello(tls_state_t *tls) +{ + struct client_hello { + struct record_hdr xhdr; + uint8_t type; + uint8_t len24_hi, len24_mid, len24_lo; + uint8_t proto_maj, proto_min; + uint8_t rand32[32]; + uint8_t session_id_len; + /* uint8_t session_id[]; */ + uint8_t cipherid_len16_hi, cipherid_len16_lo; + uint8_t cipherid[2 * 1]; /* actually variable */ + uint8_t comprtypes_len; + uint8_t comprtypes[1]; /* actually variable */ + }; + struct client_hello hello; + + memset(&hello, 0, sizeof(hello)); + hello.xhdr.type = RECORD_TYPE_HANDSHAKE; + hello.xhdr.proto_maj = TLS_MAJ; + hello.xhdr.proto_min = TLS_MIN; + //zero: hello.xhdr.len16_hi = (sizeof(hello) - sizeof(hello.xhdr)) >> 8; + hello.xhdr.len16_lo = (sizeof(hello) - sizeof(hello.xhdr)); + hello.type = HANDSHAKE_CLIENT_HELLO; + //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; /* 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; + hello.cipherid_len16_lo = 2 * 1; + hello.cipherid[0] = CIPHER_ID >> 8; + hello.cipherid[1] = CIPHER_ID & 0xff; + hello.comprtypes_len = 1; + //hello.comprtypes[0] = 0; + + xwrite(tls->fd, &hello, sizeof(hello)); +#if 0 /* dump */ + for (;;) { + uint8_t buf[16*1024]; + sleep(2); + len = recv(tls->fd, buf, sizeof(buf), 0); //MSG_DONTWAIT); + if (len < 0) { + if (errno == EAGAIN) + continue; + bb_perror_msg_and_die("recv"); + } + if (len == 0) + break; + dump(buf, len); + } +#endif +} + +static void get_server_hello(tls_state_t *tls) +{ + struct server_hello { + struct record_hdr xhdr; + uint8_t type; + uint8_t len24_hi, len24_mid, len24_lo; + uint8_t proto_maj, proto_min; + uint8_t rand32[32]; /* first 4 bytes are unix time in BE format */ + uint8_t session_id_len; + uint8_t session_id[32]; + uint8_t cipherid_hi, cipherid_lo; + uint8_t comprtype; + /* extensions may follow, but only those which client offered in its Hello */ + }; + struct server_hello *hp; + + xread_tls_handshake_block(tls, 74); + + hp = (void*)tls->inbuf; + // 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 + if (hp->type != HANDSHAKE_SERVER_HELLO + || hp->len24_hi != 0 + || hp->len24_mid != 0 + || hp->len24_lo != 70 + || hp->proto_maj != TLS_MAJ + || hp->proto_min != TLS_MIN + || hp->session_id_len != 32 + || hp->cipherid_hi != (CIPHER_ID >> 8) + || hp->cipherid_lo != (CIPHER_ID & 0xff) + || hp->comprtype != 0 + ) { + tls_error_die(tls); + } + dbg("got SERVER_HELLO\n"); +} + +static void get_server_cert(tls_state_t *tls) { struct record_hdr *xhdr; uint8_t *certbuf; @@ -605,63 +623,6 @@ static void get_server_cert_or_die(tls_state_t *tls) static void send_client_key_exchange(tls_state_t *tls) { -#if 0 //matrixssl code snippets: - int32 csRsaEncryptPub(psPool_t *pool, psPubKey_t *key, - unsigned char *in, uint32 inlen, unsigned char *out, uint32 outlen, - void *data) - { - psAssert(key->type == PS_RSA); - return psRsaEncryptPub(pool, (psRsaKey_t*)key->key, in, inlen, out, outlen, - data); - } -... - /* pkaAfter.user is buffer len */ - if ((rc = csRsaEncryptPub(pka->pool, &ssl->sec.cert->publicKey, - ssl->sec.premaster, ssl->sec.premasterSize, pka->outbuf, - pka->user, pka->data)) < 0) { - if (rc == PS_PENDING) { - /* For these ClientKeyExchange paths, we do want to come - back through nowDoCkePka for a double pass so each - case can manage its own pkaAfter and to make sure - psX509FreeCert and sslCreateKeys() are hit below. */ - return rc; - } - psTraceIntInfo("csRsaEncryptPub in CKE failed %d\n", rc); - return MATRIXSSL_ERROR; - } - /* RSA closed the pool on second pass */ - pka->pool = NULL; - clearPkaAfter(ssl); -... -#ifdef USE_RSA_CIPHER_SUITE -/* - Standard RSA suite -*/ - ssl->sec.premasterSize = SSL_HS_RSA_PREMASTER_SIZE; - ssl->sec.premaster = psMalloc(ssl->hsPool, - SSL_HS_RSA_PREMASTER_SIZE); - if (ssl->sec.premaster == NULL) { - return SSL_MEM_ERROR; - } - - ssl->sec.premaster[0] = ssl->reqMajVer; - ssl->sec.premaster[1] = ssl->reqMinVer; - if (matrixCryptoGetPrngData(ssl->sec.premaster + 2, - SSL_HS_RSA_PREMASTER_SIZE - 2, ssl->userPtr) < 0) { - return MATRIXSSL_ERROR; - } - - /* Shedule RSA encryption. Put tmp pool under control of After */ - pkaAfter->type = PKA_AFTER_RSA_ENCRYPT; - pkaAfter->outbuf = c; - pkaAfter->data = pkiData; - pkaAfter->pool = pkiPool; - pkaAfter->user = (uint32)(end - c); /* Available space */ - - c += keyLen; -#endif -#endif // 0 - struct client_key_exchange { struct record_hdr xhdr; uint8_t type; @@ -675,7 +636,7 @@ static void send_client_key_exchange(tls_state_t *tls) uint8_t key[384]; // size?? }; struct client_key_exchange record; - uint8_t premaster[SSL_HS_RSA_PREMASTER_SIZE]; + uint8_t rsa_premaster[SSL_HS_RSA_PREMASTER_SIZE]; memset(&record, 0, sizeof(record)); record.xhdr.type = RECORD_TYPE_HANDSHAKE; @@ -690,12 +651,16 @@ static void send_client_key_exchange(tls_state_t *tls) record.keylen16_hi = (sizeof(record) - sizeof(record.xhdr) - 6) >> 8; record.keylen16_lo = (sizeof(record) - sizeof(record.xhdr) - 6) & 0xff; - tls_get_random(premaster, sizeof(premaster)); - premaster[0] = TLS_MAJ; - premaster[1] = TLS_MIN; + tls_get_random(rsa_premaster, sizeof(rsa_premaster)); +// RFC 5246 +// "Note: The version number in the PreMasterSecret is the version +// offered by the client in the ClientHello.client_version, not the +// version negotiated for the connection." + rsa_premaster[0] = TLS_MAJ; + rsa_premaster[1] = TLS_MIN; psRsaEncryptPub(/*pool:*/ NULL, /* psRsaKey_t* */ &tls->server_rsa_pub_key, - premaster, /*inlen:*/ sizeof(premaster), + rsa_premaster, /*inlen:*/ sizeof(rsa_premaster), record.key, sizeof(record.key), data_param_ignored ); @@ -712,6 +677,88 @@ static void send_change_cipher_spec(tls_state_t *tls) xwrite(tls->fd, rec, sizeof(rec)); } +static void send_client_finished(tls_state_t *tls) +{ +// RFC 5246 on pseudorandom function (PRF): +// +// 5. HMAC and the Pseudorandom Function +//... +// In this section, we define one PRF, based on HMAC. This PRF with the +// SHA-256 hash function is used for all cipher suites defined in this +// document and in TLS documents published prior to this document when +// TLS 1.2 is negotiated. +//... +// P_hash(secret, seed) = HMAC_hash(secret, A(1) + seed) + +// HMAC_hash(secret, A(2) + seed) + +// HMAC_hash(secret, A(3) + seed) + ... +// where + indicates concatenation. +// A() is defined as: +// A(0) = seed +// A(i) = HMAC_hash(secret, A(i-1)) +// P_hash can be iterated as many times as necessary to produce the +// required quantity of data. For example, if P_SHA256 is being used to +// create 80 bytes of data, it will have to be iterated three times +// (through A(3)), creating 96 bytes of output data; the last 16 bytes +// of the final iteration will then be discarded, leaving 80 bytes of +// output data. +// +// TLS's PRF is created by applying P_hash to the secret as: +// +// PRF(secret, label, seed) = P_<hash>(secret, label + seed) +// +// The label is an ASCII string. + + tls->fd = 0; + +// 7.4.9. Finished +// A Finished message is always sent immediately after a change +// cipher spec message to verify that the key exchange and +// authentication processes were successful. It is essential that a +// change cipher spec message be received between the other handshake +// messages and the Finished message. +//... +// The Finished message is the first one protected with the just +// negotiated algorithms, keys, and secrets. Recipients of Finished +// messages MUST verify that the contents are correct. Once a side +// has sent its Finished message and received and validated the +// Finished message from its peer, it may begin to send and receive +// application data over the connection. +//... +// struct { +// opaque verify_data[verify_data_length]; +// } Finished; +// +// verify_data +// PRF(master_secret, finished_label, Hash(handshake_messages)) +// [0..verify_data_length-1]; +// +// finished_label +// For Finished messages sent by the client, the string +// "client finished". For Finished messages sent by the server, +// the string "server finished". +// +// Hash denotes a Hash of the handshake messages. For the PRF +// defined in Section 5, the Hash MUST be the Hash used as the basis +// for the PRF. Any cipher suite which defines a different PRF MUST +// also define the Hash to use in the Finished computation. +// +// In previous versions of TLS, the verify_data was always 12 octets +// long. In the current version of TLS, it depends on the cipher +// suite. Any cipher suite which does not explicitly specify +// verify_data_length has a verify_data_length equal to 12. This +// includes all existing cipher suites. +} + +static void get_change_cipher_spec(tls_state_t *tls) +{ + tls->fd = 0; +} + +static void get_server_finished(tls_state_t *tls) +{ + tls->fd = 0; +} + static void tls_handshake(tls_state_t *tls) { // Client RFC 5246 Server @@ -734,23 +781,7 @@ static void tls_handshake(tls_state_t *tls) int len; send_client_hello(tls); -#if 0 /* dump */ - for (;;) { - uint8_t buf[16*1024]; - sleep(2); - len = recv(tls->fd, buf, sizeof(buf), 0); //MSG_DONTWAIT); - if (len < 0) { - if (errno == EAGAIN) - continue; - bb_perror_msg_and_die("recv"); - } - if (len == 0) - break; - dump(buf, len); - } -#endif - - get_server_hello_or_die(tls); + get_server_hello(tls); //RFC 5246 // The server MUST send a Certificate message whenever the agreed- @@ -761,7 +792,7 @@ static void tls_handshake(tls_state_t *tls) // // IOW: in practice, Certificate *always* follows. // (for example, kernel.org does not even accept DH_anon cipher id) - get_server_cert_or_die(tls); + get_server_cert(tls); len = xread_tls_handshake_block(tls, 4); if (tls->inbuf[5] == HANDSHAKE_SERVER_KEY_EXCHANGE) { @@ -776,6 +807,13 @@ static void tls_handshake(tls_state_t *tls) } // if (tls->inbuf[5] == HANDSHAKE_CERTIFICATE_REQUEST) { // dbg("got 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) // xread_tls_handshake_block(tls, 4); // } if (tls->inbuf[5] == HANDSHAKE_SERVER_HELLO_DONE) { @@ -784,6 +822,10 @@ static void tls_handshake(tls_state_t *tls) send_client_key_exchange(tls); send_change_cipher_spec(tls); //we now should be able to send encrypted... as soon as we grok AES. + send_client_finished(tls); + get_change_cipher_spec(tls); + get_server_finished(tls); +//we now should receive encrypted, and application data can be sent/received } else { tls_error_die(tls); } |