diff options
| -rw-r--r-- | networking/tls.c | 204 |
1 files changed, 117 insertions, 87 deletions
diff --git a/networking/tls.c b/networking/tls.c index 66d62fe3d..e76a78585 100644 --- a/networking/tls.c +++ b/networking/tls.c @@ -19,6 +19,10 @@ #include "tls.h" +// works against "openssl s_server -cipher NULL" +// and against wolfssl-3.9.10-stable/examples/server/server.c: +#define ALLOW_RSA_NULL_SHA256 0 // for testing (does everything except encrypting) + //Tested against kernel.org: //#define CIPHER_ID TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA // ok, recvs SERVER_KEY_EXCHANGE *** matrixssl uses this on my box //#define CIPHER_ID TLS_RSA_WITH_AES_256_CBC_SHA256 // ok, no SERVER_KEY_EXCHANGE @@ -35,10 +39,6 @@ //#define CIPHER_ID TLS_RSA_WITH_AES_256_GCM_SHA384 // ok, no SERVER_KEY_EXCHANGE //#define CIPHER_ID TLS_RSA_WITH_AES_128_GCM_SHA256 // ok, no SERVER_KEY_EXCHANGE -// works against "openssl s_server -cipher NULL" -// and against wolfssl-3.9.10-stable/examples/server/server.c: -//#define CIPHER_ID1 TLS_RSA_WITH_NULL_SHA256 // for testing (does everything except encrypting) - // works against wolfssl-3.9.10-stable/examples/server/server.c // works for kernel.org // does not work for cdn.kernel.org (e.g. downloading an actual tarball, not a web page) @@ -50,41 +50,15 @@ // ok: openssl s_client -connect cdn.kernel.org:443 -debug -tls1_2 -no_tls1 -no_tls1_1 -cipher AES128-GCM-SHA256 // ok: openssl s_client -connect cdn.kernel.org:443 -debug -tls1_2 -no_tls1 -no_tls1_1 -cipher AES128-SHA // (TLS_RSA_WITH_AES_128_CBC_SHA - in TLS 1.2 it's mandated to be always supported) -#define CIPHER_ID1 TLS_RSA_WITH_AES_256_CBC_SHA256 //0x003D +//#define CIPHER_ID1 TLS_RSA_WITH_AES_256_CBC_SHA256 //0x003D // Works with "wget https://cdn.kernel.org/pub/linux/kernel/v4.x/linux-4.9.5.tar.xz" -#define CIPHER_ID2 TLS_RSA_WITH_AES_128_CBC_SHA //0x002F +//#define CIPHER_ID2 TLS_RSA_WITH_AES_128_CBC_SHA //0x002F // bug #11456: // ftp.openbsd.org only supports ECDHE-RSA-AESnnn-GCM-SHAnnn or ECDHE-RSA-CHACHA20-POLY1305 -#define CIPHER_ID3 TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 //0xC02F +//#define CIPHER_ID3 TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 //0xC02F // host is.gd accepts only ECDHE-ECDSA-foo (the simplest which works: ECDHE-ECDSA-AES128-SHA 0xC009) -#define CIPHER_ID4 TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA //0xC009 - -#define NUM_CIPHERS 4 -//TODO: we can support all these: -// TLS_RSA_WITH_AES_128_CBC_SHA 0x002F -// TLS_RSA_WITH_AES_256_CBC_SHA 0x0035 -// TLS_RSA_WITH_AES_128_CBC_SHA256 0x003C -// TLS_RSA_WITH_AES_256_CBC_SHA256 0x003D -// TLS_RSA_WITH_AES_128_GCM_SHA256 0x009C -// TLS_RSA_WITH_AES_256_GCM_SHA384 0x009D -// TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA 0xC009 -// TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA 0xC00A -// TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA 0xC013 -// TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA 0xC014 -// TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256 0xC023 -////TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384 0xC024 - can't do SHA384 yet -// TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256 0xC027 -////TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384 0xC028 - can't do SHA384 yet -// TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 0xC02B -// TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 0xC02C -// TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 0xC02F -// TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 0xC030 -//possibly these too: -// TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA 0xC035 -// TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA 0xC036 -// TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA256 0xC037 -////TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA384 0xC038 - can't do SHA384 yet +//#define CIPHER_ID4 TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA //0xC009 #define TLS_DEBUG 0 @@ -291,7 +265,7 @@ enum { GOT_CERT_RSA_KEY_ALG = 1 << 1, GOT_CERT_ECDSA_KEY_ALG = 1 << 2, // so far unused GOT_EC_KEY = 1 << 3, - ENCRYPTION_AESGCM = 1 << 4, // else AES-SHA (or NULL-SHA if CIPHER_ID1 set to allow one) + ENCRYPTION_AESGCM = 1 << 4, // else AES-SHA (or NULL-SHA if ALLOW_RSA_NULL_SHA256=1) ENCRYPT_ON_WRITE = 1 << 5, }; @@ -676,7 +650,7 @@ static void xwrite_encrypted_and_hmac_signed(tls_state_t *tls, unsigned size, un uint8_t padding_length; xhdr = (void*)(buf - RECHDR_LEN); - if (CIPHER_ID1 != TLS_RSA_WITH_NULL_SHA256 /* if "no encryption" can't be selected */ + if (!ALLOW_RSA_NULL_SHA256 /* if "no encryption" can't be selected */ || tls->cipher_id != TLS_RSA_WITH_NULL_SHA256 /* or if it wasn't selected */ ) { xhdr = (void*)(buf - RECHDR_LEN - AES_BLOCK_SIZE); /* place for IV */ @@ -734,7 +708,7 @@ static void xwrite_encrypted_and_hmac_signed(tls_state_t *tls, unsigned size, un // -------- ----------- ---------- -------------- // SHA HMAC-SHA1 20 20 // SHA256 HMAC-SHA256 32 32 - if (CIPHER_ID1 == TLS_RSA_WITH_NULL_SHA256 + if (ALLOW_RSA_NULL_SHA256 && tls->cipher_id == TLS_RSA_WITH_NULL_SHA256 ) { /* No encryption, only signing */ @@ -1478,6 +1452,39 @@ static ALWAYS_INLINE void fill_handshake_record_hdr(void *buf, unsigned type, un static void send_client_hello_and_alloc_hsd(tls_state_t *tls, const char *sni) { +#define NUM_CIPHERS (12 + ALLOW_RSA_NULL_SHA256) + static const uint8_t ciphers[] = { + 0x00,(1 + NUM_CIPHERS) * 2, //len16_be + 0x00,0xFF, //not a cipher - TLS_EMPTY_RENEGOTIATION_INFO_SCSV + /* ^^^^^^ RFC 5746 Renegotiation Indication Extension - some servers will refuse to work with us otherwise */ + 0xC0,0x09, // 1 TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA - ok: wget https://is.gd/ + 0xC0,0x0A, // 2 TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA - ok: wget https://is.gd/ + 0xC0,0x13, // 3 TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA - ok: openssl s_server ... -cipher ECDHE-RSA-AES128-SHA + // 0xC0,0x14, // TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA - openssl s_server ... -cipher ECDHE-RSA-AES256-SHA: "No ciphers enabled for max supported SSL/TLS version" + 0xC0,0x23, // 4 TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256 - ok: wget https://is.gd/ + // 0xC0,0x24, // TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384 - can't do SHA384 yet + 0xC0,0x27, // 5 TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256 - ok: openssl s_server ... -cipher ECDHE-RSA-AES128-SHA256 + // 0xC0,0x28, // TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384 - can't do SHA384 yet + 0xC0,0x2B, // 6 TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 - ok: wget https://is.gd/ + // 0xC0,0x2C, // TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 - wget https://is.gd/: "TLS error from peer (alert code 20): bad MAC" + 0xC0,0x2F, // 7 TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 - ok: openssl s_server ... -cipher ECDHE-RSA-AES128-GCM-SHA256 + // 0xC0,0x30, // TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 - openssl s_server ... -cipher ECDHE-RSA-AES256-GCM-SHA384: "decryption failed or bad record mac" + //possibly these too: + // 0xC0,0x35, // TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA + // 0xC0,0x36, // TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA + // 0xC0,0x37, // TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA256 + // 0xC0,0x38, // TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA384 - can't do SHA384 yet + 0x00,0x2F, // 8 TLS_RSA_WITH_AES_128_CBC_SHA - ok: openssl s_server ... -cipher AES128-SHA + 0x00,0x35, // 9 TLS_RSA_WITH_AES_256_CBC_SHA - ok: openssl s_server ... -cipher AES256-SHA + 0x00,0x3C, //10 TLS_RSA_WITH_AES_128_CBC_SHA256 - ok: openssl s_server ... -cipher AES128-SHA256 + 0x00,0x3D, //11 TLS_RSA_WITH_AES_256_CBC_SHA256 - ok: openssl s_server ... -cipher AES256-SHA256 + 0x00,0x9C, //12 TLS_RSA_WITH_AES_128_GCM_SHA256 - ok: openssl s_server ... -cipher AES128-GCM-SHA256 + // 0x00,0x9D, // TLS_RSA_WITH_AES_256_GCM_SHA384 - openssl s_server ... -cipher AES256-GCM-SHA384: "decryption failed or bad record mac" +#if ALLOW_RSA_NULL_SHA256 + 0x00,0x3B, // TLS_RSA_WITH_NULL_SHA256 +#endif + 0x01,0x00, //not a cipher - comprtypes_len, comprtype + }; static const uint8_t supported_groups[] = { 0x00,0x0a, //extension_type: "supported_groups" 0x00,0x04, //ext len @@ -1502,7 +1509,7 @@ static void send_client_hello_and_alloc_hsd(tls_state_t *tls, const char *sni) uint8_t session_id_len; /* uint8_t session_id[]; */ uint8_t cipherid_len16_hi, cipherid_len16_lo; - uint8_t cipherid[2 * (1 + NUM_CIPHERS)]; /* actually variable */ + uint8_t cipherid[(1 + NUM_CIPHERS) * 2]; /* actually variable */ uint8_t comprtypes_len; uint8_t comprtypes[1]; /* actually variable */ /* Extensions (SNI shown): @@ -1550,28 +1557,8 @@ static void send_client_hello_and_alloc_hsd(tls_state_t *tls, const char *sni) memset(record->rand32, 0x11, sizeof(record->rand32)); /* record->session_id_len = 0; - already is */ - /* record->cipherid_len16_hi = 0; */ - record->cipherid_len16_lo = sizeof(record->cipherid); - /* RFC 5746 Renegotiation Indication Extension - some servers will refuse to work with us otherwise */ - /*record->cipherid[0] = TLS_EMPTY_RENEGOTIATION_INFO_SCSV >> 8; - zero */ - record->cipherid[1] = TLS_EMPTY_RENEGOTIATION_INFO_SCSV & 0xff; - if ((CIPHER_ID1 >> 8) != 0) record->cipherid[2] = CIPHER_ID1 >> 8; - /*************************/ record->cipherid[3] = CIPHER_ID1 & 0xff; -#if CIPHER_ID2 - if ((CIPHER_ID2 >> 8) != 0) record->cipherid[4] = CIPHER_ID2 >> 8; - /*************************/ record->cipherid[5] = CIPHER_ID2 & 0xff; -#endif -#if CIPHER_ID3 - if ((CIPHER_ID3 >> 8) != 0) record->cipherid[6] = CIPHER_ID3 >> 8; - /*************************/ record->cipherid[7] = CIPHER_ID3 & 0xff; -#endif -#if CIPHER_ID4 - if ((CIPHER_ID4 >> 8) != 0) record->cipherid[8] = CIPHER_ID4 >> 8; - /*************************/ record->cipherid[9] = CIPHER_ID4 & 0xff; -#endif - - record->comprtypes_len = 1; - /* record->comprtypes[0] = 0; */ + BUILD_BUG_ON(sizeof(ciphers) != 2 + (1 + NUM_CIPHERS) * 2 + 2); + memcpy(&record->cipherid_len16_hi, ciphers, sizeof(ciphers)); ptr = (void*)(record + 1); *ptr++ = ext_len >> 8; @@ -1626,6 +1613,7 @@ static void get_server_hello(tls_state_t *tls) struct server_hello *hp; uint8_t *cipherid; + uint8_t cipherid1; unsigned cipher; int len, len24; @@ -1659,39 +1647,81 @@ static void get_server_hello(tls_state_t *tls) len24 += 32; /* what len would be if session id would be present */ } - if (len24 < 70 -// || cipherid[0] != (CIPHER_ID >> 8) -// || cipherid[1] != (CIPHER_ID & 0xff) -// || cipherid[2] != 0 /* comprtype */ - ) { + if (len24 < 70) bad_record_die(tls, "'server hello'", len); - } dbg("<< SERVER_HELLO\n"); memcpy(tls->hsd->client_and_server_rand32 + 32, hp->rand32, sizeof(hp->rand32)); - tls->cipher_id = cipher = 0x100 * cipherid[0] + cipherid[1]; + /* Set up encryption params based on selected cipher */ +#if 0 + 0xC0,0x09, // 1 TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA - ok: wget https://is.gd/ + 0xC0,0x0A, // 2 TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA - ok: wget https://is.gd/ + 0xC0,0x13, // 3 TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA - ok: openssl s_server ... -cipher ECDHE-RSA-AES128-SHA + // 0xC0,0x14, // TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA - openssl s_server ... -cipher ECDHE-RSA-AES256-SHA: "No ciphers enabled for max supported SSL/TLS version" + 0xC0,0x23, // 4 TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256 - ok: wget https://is.gd/ + // 0xC0,0x24, // TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384 - can't do SHA384 yet + 0xC0,0x27, // 5 TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256 - ok: openssl s_server ... -cipher ECDHE-RSA-AES128-SHA256 + // 0xC0,0x28, // TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384 - can't do SHA384 yet + 0xC0,0x2B, // 6 TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 - ok: wget https://is.gd/ + // 0xC0,0x2C, // TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 - wget https://is.gd/: "TLS error from peer (alert code 20): bad MAC" + 0xC0,0x2F, // 7 TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 - ok: openssl s_server ... -cipher ECDHE-RSA-AES128-GCM-SHA256 + // 0xC0,0x30, // TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 - openssl s_server ... -cipher ECDHE-RSA-AES256-GCM-SHA384: "decryption failed or bad record mac" + //possibly these too: + // 0xC0,0x35, // TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA + // 0xC0,0x36, // TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA + // 0xC0,0x37, // TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA256 + // 0xC0,0x38, // TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA384 - can't do SHA384 yet + 0x00,0x2F, // 8 TLS_RSA_WITH_AES_128_CBC_SHA - ok: openssl s_server ... -cipher AES128-SHA + 0x00,0x35, // 9 TLS_RSA_WITH_AES_256_CBC_SHA - ok: openssl s_server ... -cipher AES256-SHA + 0x00,0x3C, //10 TLS_RSA_WITH_AES_128_CBC_SHA256 - ok: openssl s_server ... -cipher AES128-SHA256 + 0x00,0x3D, //11 TLS_RSA_WITH_AES_256_CBC_SHA256 - ok: openssl s_server ... -cipher AES256-SHA256 + 0x00,0x9C, //12 TLS_RSA_WITH_AES_128_GCM_SHA256 - ok: openssl s_server ... -cipher AES128-GCM-SHA256 + // 0x00,0x9D, // TLS_RSA_WITH_AES_256_GCM_SHA384 - openssl s_server ... -cipher AES256-GCM-SHA384: "decryption failed or bad record mac" + 0x00,0x3B, // TLS_RSA_WITH_NULL_SHA256 +#endif + cipherid1 = cipherid[1]; + tls->cipher_id = cipher = 0x100 * cipherid[0] + cipherid1; dbg("server chose cipher %04x\n", cipher); - - if (cipher == TLS_RSA_WITH_AES_128_CBC_SHA - || cipher == TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA - ) { - if (cipher == TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA) - tls->flags |= NEED_EC_KEY; - tls->key_size = AES128_KEYSIZE; - tls->MAC_size = SHA1_OUTSIZE; - } - else - if (cipher == TLS_RSA_WITH_AES_256_CBC_SHA256) { - tls->key_size = AES256_KEYSIZE; - tls->MAC_size = SHA256_OUTSIZE; - } - else { /* TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 */ - tls->flags |= NEED_EC_KEY | ENCRYPTION_AESGCM; - tls->key_size = AES128_KEYSIZE; - /* tls->MAC_size = 0; */ - tls->IV_size = 4; + tls->key_size = AES256_KEYSIZE; + tls->MAC_size = SHA256_OUTSIZE; + /*tls->IV_size = 0; - already is */ + if (cipherid[0] == 0xC0) { + /* All C0xx are ECDHE */ + tls->flags |= NEED_EC_KEY; + if (cipherid1 & 1) { + /* Odd numbered C0xx use AES128 (even ones use AES256) */ + tls->key_size = AES128_KEYSIZE; + } + if (cipherid1 <= 0x14) { + tls->MAC_size = SHA1_OUTSIZE; + } else + if (cipherid1 >= 0x2B && cipherid1 <= 0x30) { + /* C02B,2C,2F,30 are AES-GCM */ + tls->flags |= ENCRYPTION_AESGCM; + tls->MAC_size = 0; + tls->IV_size = 4; + } + } else { + /* All 00xx are RSA */ + if (cipherid1 == 0x2F + || cipherid1 == 0x3C + || cipherid1 == 0x9C + ) { + tls->key_size = AES128_KEYSIZE; + } + if (cipherid1 <= 0x35) { + tls->MAC_size = SHA1_OUTSIZE; + } else + if (cipherid1 == 0x9C || cipherid1 == 0x9D) { + /* 009C,9D are AES-GCM */ + tls->flags |= ENCRYPTION_AESGCM; + tls->MAC_size = 0; + tls->IV_size = 4; + } } + dbg("key_size:%u MAC_size:%u IV_size:%u\n", tls->key_size, tls->MAC_size, tls->IV_size); + /* Handshake hash eventually destined to FINISHED record * is sha256 regardless of cipher * (at least for all ciphers defined by RFC5246). @@ -2171,7 +2201,7 @@ void FAST_FUNC tls_handshake(tls_state_t *tls, const char *sni) bad_record_die(tls, "switch to encrypted traffic", len); dbg("<< CHANGE_CIPHER_SPEC\n"); - if (CIPHER_ID1 == TLS_RSA_WITH_NULL_SHA256 + if (ALLOW_RSA_NULL_SHA256 && tls->cipher_id == TLS_RSA_WITH_NULL_SHA256 ) { tls->min_encrypted_len_on_read = tls->MAC_size; 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