* Licensed under GPLv2, see file LICENSE in this source tree.
*/
//config:config TLS
-//config: bool "tls (debugging)"
+//config: bool #No description makes it a hidden option
//config: default n
-
-//applet:IF_TLS(APPLET(tls, BB_DIR_USR_BIN, BB_SUID_DROP))
+//Note:
+//Config.src also defines FEATURE_TLS_SHA1 option
//kbuild:lib-$(CONFIG_TLS) += tls.o
//kbuild:lib-$(CONFIG_TLS) += tls_pstm.o
//kbuild:lib-$(CONFIG_TLS) += tls_pstm_montgomery_reduce.o
//kbuild:lib-$(CONFIG_TLS) += tls_pstm_mul_comba.o
//kbuild:lib-$(CONFIG_TLS) += tls_pstm_sqr_comba.o
+//kbuild:lib-$(CONFIG_TLS) += tls_aes.o
+//kbuild:lib-$(CONFIG_TLS) += tls_aesgcm.o
//kbuild:lib-$(CONFIG_TLS) += tls_rsa.o
-////kbuild:lib-$(CONFIG_TLS) += tls_ciphers.o
-////kbuild:lib-$(CONFIG_TLS) += tls_aes.o
-////kbuild:lib-$(CONFIG_TLS) += tls_aes_gcm.o
-
-//usage:#define tls_trivial_usage
-//usage: "HOST[:PORT]"
-//usage:#define tls_full_usage "\n\n"
+//kbuild:lib-$(CONFIG_TLS) += tls_fe.o
#include "tls.h"
-#if 1
+// 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
+//#define CIPHER_ID TLS_DH_anon_WITH_AES_256_CBC_SHA // SSL_ALERT_HANDSHAKE_FAILURE
+//^^^^^^^^^^^^^^^^^^^^^^^ (tested b/c this one doesn't req server certs... no luck, server refuses it)
+//#define CIPHER_ID TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 // SSL_ALERT_HANDSHAKE_FAILURE
+//#define CIPHER_ID TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 // SSL_ALERT_HANDSHAKE_FAILURE
+//#define CIPHER_ID TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 // ok, recvs SERVER_KEY_EXCHANGE
+//#define CIPHER_ID TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256
+//#define CIPHER_ID TLS_ECDH_ECDSA_WITH_AES_256_GCM_SHA384
+//#define CIPHER_ID TLS_ECDH_ECDSA_WITH_AES_128_GCM_SHA256 // SSL_ALERT_HANDSHAKE_FAILURE
+//#define CIPHER_ID TLS_ECDH_RSA_WITH_AES_256_GCM_SHA384
+//#define CIPHER_ID TLS_ECDH_RSA_WITH_AES_128_GCM_SHA256 // SSL_ALERT_HANDSHAKE_FAILURE
+//#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 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)
+// getting alert 40 "handshake failure" at once
+// with GNU Wget 1.18, they agree on TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (0xC02F) cipher
+// fail: openssl s_client -connect cdn.kernel.org:443 -debug -tls1_2 -cipher AES256-SHA256
+// fail: openssl s_client -connect cdn.kernel.org:443 -debug -tls1_2 -cipher AES256-GCM-SHA384
+// fail: openssl s_client -connect cdn.kernel.org:443 -debug -tls1_2 -cipher AES128-SHA256
+// ok: openssl s_client -connect cdn.kernel.org:443 -debug -tls1_2 -cipher AES128-GCM-SHA256
+// ok: openssl s_client -connect cdn.kernel.org:443 -debug -tls1_2 -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
+// 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
+
+// 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
+// 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 TLS_DEBUG 0
+#define TLS_DEBUG_HASH 0
+#define TLS_DEBUG_DER 0
+#define TLS_DEBUG_FIXED_SECRETS 0
+#if 0
+# define dump_raw_out(...) dump_hex(__VA_ARGS__)
+#else
+# define dump_raw_out(...) ((void)0)
+#endif
+#if 0
+# define dump_raw_in(...) dump_hex(__VA_ARGS__)
+#else
+# define dump_raw_in(...) ((void)0)
+#endif
+
+#if TLS_DEBUG
# define dbg(...) fprintf(stderr, __VA_ARGS__)
#else
# define dbg(...) ((void)0)
#endif
-#define RECORD_TYPE_CHANGE_CIPHER_SPEC 20
-#define RECORD_TYPE_ALERT 21
-#define RECORD_TYPE_HANDSHAKE 22
-#define RECORD_TYPE_APPLICATION_DATA 23
-
-#define HANDSHAKE_HELLO_REQUEST 0
-#define HANDSHAKE_CLIENT_HELLO 1
-#define HANDSHAKE_SERVER_HELLO 2
-#define HANDSHAKE_HELLO_VERIFY_REQUEST 3
-#define HANDSHAKE_NEW_SESSION_TICKET 4
-#define HANDSHAKE_CERTIFICATE 11
-#define HANDSHAKE_SERVER_KEY_EXCHANGE 12
-#define HANDSHAKE_CERTIFICATE_REQUEST 13
-#define HANDSHAKE_SERVER_HELLO_DONE 14
-#define HANDSHAKE_CERTIFICATE_VERIFY 15
-#define HANDSHAKE_CLIENT_KEY_EXCHANGE 16
-#define HANDSHAKE_FINISHED 20
-
-#define SSL_HS_RANDOM_SIZE 32
-#define SSL_HS_RSA_PREMASTER_SIZE 48
+#if TLS_DEBUG_DER
+# define dbg_der(...) fprintf(stderr, __VA_ARGS__)
+#else
+# define dbg_der(...) ((void)0)
+#endif
+
+
+//TLS 1.2
+#define TLS_MAJ 3
+#define TLS_MIN 3
+
+#define RECORD_TYPE_CHANGE_CIPHER_SPEC 20 /* 0x14 */
+#define RECORD_TYPE_ALERT 21 /* 0x15 */
+#define RECORD_TYPE_HANDSHAKE 22 /* 0x16 */
+#define RECORD_TYPE_APPLICATION_DATA 23 /* 0x17 */
+
+#define HANDSHAKE_HELLO_REQUEST 0 /* 0x00 */
+#define HANDSHAKE_CLIENT_HELLO 1 /* 0x01 */
+#define HANDSHAKE_SERVER_HELLO 2 /* 0x02 */
+#define HANDSHAKE_HELLO_VERIFY_REQUEST 3 /* 0x03 */
+#define HANDSHAKE_NEW_SESSION_TICKET 4 /* 0x04 */
+#define HANDSHAKE_CERTIFICATE 11 /* 0x0b */
+#define HANDSHAKE_SERVER_KEY_EXCHANGE 12 /* 0x0c */
+#define HANDSHAKE_CERTIFICATE_REQUEST 13 /* 0x0d */
+#define HANDSHAKE_SERVER_HELLO_DONE 14 /* 0x0e */
+#define HANDSHAKE_CERTIFICATE_VERIFY 15 /* 0x0f */
+#define HANDSHAKE_CLIENT_KEY_EXCHANGE 16 /* 0x10 */
+#define HANDSHAKE_FINISHED 20 /* 0x14 */
+
+#define TLS_EMPTY_RENEGOTIATION_INFO_SCSV 0x00FF /* not a real cipher id... */
#define SSL_NULL_WITH_NULL_NULL 0x0000
#define SSL_RSA_WITH_NULL_MD5 0x0001
#define SSL_RSA_WITH_NULL_SHA 0x0002
#define SSL_RSA_WITH_RC4_128_MD5 0x0004
#define SSL_RSA_WITH_RC4_128_SHA 0x0005
+#define TLS_RSA_WITH_IDEA_CBC_SHA 0x0007 /* 7 */
#define SSL_RSA_WITH_3DES_EDE_CBC_SHA 0x000A /* 10 */
-#define TLS_RSA_WITH_AES_128_CBC_SHA 0x002F /* 47 */
-#define TLS_RSA_WITH_AES_256_CBC_SHA 0x0035 /* 53 */
-#define TLS_EMPTY_RENEGOTIATION_INFO_SCSV 0x00FF
-#define TLS_RSA_WITH_IDEA_CBC_SHA 0x0007 /* 7 */
#define SSL_DHE_RSA_WITH_3DES_EDE_CBC_SHA 0x0016 /* 22 */
#define SSL_DH_anon_WITH_RC4_128_MD5 0x0018 /* 24 */
#define SSL_DH_anon_WITH_3DES_EDE_CBC_SHA 0x001B /* 27 */
+#define TLS_RSA_WITH_AES_128_CBC_SHA 0x002F /*SSLv3 Kx=RSA Au=RSA Enc=AES(128) Mac=SHA1 */
#define TLS_DHE_RSA_WITH_AES_128_CBC_SHA 0x0033 /* 51 */
-#define TLS_DHE_RSA_WITH_AES_256_CBC_SHA 0x0039 /* 57 */
-#define TLS_DHE_RSA_WITH_AES_128_CBC_SHA256 0x0067 /* 103 */
-#define TLS_DHE_RSA_WITH_AES_256_CBC_SHA256 0x006B /* 107 */
#define TLS_DH_anon_WITH_AES_128_CBC_SHA 0x0034 /* 52 */
+#define TLS_RSA_WITH_AES_256_CBC_SHA 0x0035 /* 53 */
+#define TLS_DHE_RSA_WITH_AES_256_CBC_SHA 0x0039 /* 57 */
#define TLS_DH_anon_WITH_AES_256_CBC_SHA 0x003A /* 58 */
+#define TLS_RSA_WITH_NULL_SHA256 0x003B /* 59 */
#define TLS_RSA_WITH_AES_128_CBC_SHA256 0x003C /* 60 */
#define TLS_RSA_WITH_AES_256_CBC_SHA256 0x003D /* 61 */
-#define TLS_RSA_WITH_SEED_CBC_SHA 0x0096 /* 150 */
+#define TLS_DHE_RSA_WITH_AES_128_CBC_SHA256 0x0067 /* 103 */
+#define TLS_DHE_RSA_WITH_AES_256_CBC_SHA256 0x006B /* 107 */
#define TLS_PSK_WITH_AES_128_CBC_SHA 0x008C /* 140 */
-#define TLS_PSK_WITH_AES_128_CBC_SHA256 0x00AE /* 174 */
-#define TLS_PSK_WITH_AES_256_CBC_SHA384 0x00AF /* 175 */
#define TLS_PSK_WITH_AES_256_CBC_SHA 0x008D /* 141 */
#define TLS_DHE_PSK_WITH_AES_128_CBC_SHA 0x0090 /* 144 */
#define TLS_DHE_PSK_WITH_AES_256_CBC_SHA 0x0091 /* 145 */
+#define TLS_RSA_WITH_SEED_CBC_SHA 0x0096 /* 150 */
+#define TLS_RSA_WITH_AES_128_GCM_SHA256 0x009C /*TLSv1.2 Kx=RSA Au=RSA Enc=AESGCM(128) Mac=AEAD */
+#define TLS_RSA_WITH_AES_256_GCM_SHA384 0x009D /*TLSv1.2 Kx=RSA Au=RSA Enc=AESGCM(256) Mac=AEAD */
+#define TLS_DHE_RSA_WITH_AES_128_GCM_SHA256 0x009E /*TLSv1.2 Kx=DH Au=RSA Enc=AESGCM(128) Mac=AEAD */
+#define TLS_DHE_RSA_WITH_AES_256_GCM_SHA384 0x009F /*TLSv1.2 Kx=DH Au=RSA Enc=AESGCM(256) Mac=AEAD */
+#define TLS_DH_anon_WITH_AES_128_GCM_SHA256 0x00A6 /* RFC 5288 */
+#define TLS_DH_anon_WITH_AES_256_GCM_SHA384 0x00A7 /* RFC 5288 */
+#define TLS_PSK_WITH_AES_128_CBC_SHA256 0x00AE /* 174 */
+#define TLS_PSK_WITH_AES_256_CBC_SHA384 0x00AF /* 175 */
#define TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA 0xC004 /* 49156 */
#define TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA 0xC005 /* 49157 */
-#define TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA 0xC009 /* 49161 */
-#define TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA 0xC00A /* 49162 */
-#define TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA 0xC012 /* 49170 */
-#define TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA 0xC013 /* 49171 */
-#define TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA 0xC014 /* 49172 */
+#define TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA 0xC009 /*TLSv1 Kx=ECDH Au=ECDSA Enc=AES(128) Mac=SHA1 */
+#define TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA 0xC00A /*TLSv1 Kx=ECDH Au=ECDSA Enc=AES(256) Mac=SHA1 */
#define TLS_ECDH_RSA_WITH_AES_128_CBC_SHA 0xC00E /* 49166 */
#define TLS_ECDH_RSA_WITH_AES_256_CBC_SHA 0xC00F /* 49167 */
-#define TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256 0xC023 /* 49187 */
-#define TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384 0xC024 /* 49188 */
+#define TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA 0xC012 /* 49170 */
+#define TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA 0xC013 /*TLSv1 Kx=ECDH Au=RSA Enc=AES(128) Mac=SHA1 */
+#define TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA 0xC014 /*TLSv1 Kx=ECDH Au=RSA Enc=AES(256) Mac=SHA1 */
+#define TLS_ECDH_anon_WITH_AES_128_CBC_SHA 0xC018 /* RFC 4492 */
+#define TLS_ECDH_anon_WITH_AES_256_CBC_SHA 0xC019 /* RFC 4492 */
+#define TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256 0xC023 /*TLSv1.2 Kx=ECDH Au=ECDSA Enc=AES(128) Mac=SHA256 */
+#define TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384 0xC024 /*TLSv1.2 Kx=ECDH Au=ECDSA Enc=AES(256) Mac=SHA384 */
#define TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA256 0xC025 /* 49189 */
#define TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA384 0xC026 /* 49190 */
-#define TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256 0xC027 /* 49191 */
-#define TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384 0xC028 /* 49192 */
+#define TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256 0xC027 /*TLSv1.2 Kx=ECDH Au=RSA Enc=AES(128) Mac=SHA256 */
+#define TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384 0xC028 /*TLSv1.2 Kx=ECDH Au=RSA Enc=AES(256) Mac=SHA384 */
#define TLS_ECDH_RSA_WITH_AES_128_CBC_SHA256 0xC029 /* 49193 */
#define TLS_ECDH_RSA_WITH_AES_256_CBC_SHA384 0xC02A /* 49194 */
-
-#define TLS_RSA_WITH_AES_128_GCM_SHA256 0x009C /* 156 */
-#define TLS_RSA_WITH_AES_256_GCM_SHA384 0x009D /* 157 */
-#define TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 0xC02B /* 49195 */
-#define TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 0xC02C /* 49196 */
+/* RFC 5288 "AES Galois Counter Mode (GCM) Cipher Suites for TLS" */
+#define TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 0xC02B /*TLSv1.2 Kx=ECDH Au=ECDSA Enc=AESGCM(128) Mac=AEAD */
+#define TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 0xC02C /*TLSv1.2 Kx=ECDH Au=ECDSA Enc=AESGCM(256) Mac=AEAD */
#define TLS_ECDH_ECDSA_WITH_AES_128_GCM_SHA256 0xC02D /* 49197 */
#define TLS_ECDH_ECDSA_WITH_AES_256_GCM_SHA384 0xC02E /* 49198 */
-#define TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 0xC02F /* 49199 */
-#define TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 0xC030 /* 49200 */
+#define TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 0xC02F /*TLSv1.2 Kx=ECDH Au=RSA Enc=AESGCM(128) Mac=AEAD */
+#define TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 0xC030 /*TLSv1.2 Kx=ECDH Au=RSA Enc=AESGCM(256) Mac=AEAD */
#define TLS_ECDH_RSA_WITH_AES_128_GCM_SHA256 0xC031 /* 49201 */
#define TLS_ECDH_RSA_WITH_AES_256_GCM_SHA384 0xC032 /* 49202 */
-
-//Tested against kernel.org:
-//TLS 1.1
-//#define TLS_MAJ 3
-//#define TLS_MIN 2
-//#define CIPHER_ID TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA // ok, recvs SERVER_KEY_EXCHANGE
-//TLS 1.2
-#define TLS_MAJ 3
-#define TLS_MIN 3
-//#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
-// All GCMs:
-//#define CIPHER_ID TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 // SSL_ALERT_HANDSHAKE_FAILURE
-//#define CIPHER_ID TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 // SSL_ALERT_HANDSHAKE_FAILURE
-//#define CIPHER_ID TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 // ok, recvs SERVER_KEY_EXCHANGE
-//#define CIPHER_ID TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256
-//#define CIPHER_ID TLS_ECDH_ECDSA_WITH_AES_256_GCM_SHA384
-//#define CIPHER_ID TLS_ECDH_ECDSA_WITH_AES_128_GCM_SHA256 // SSL_ALERT_HANDSHAKE_FAILURE
-//#define CIPHER_ID TLS_ECDH_RSA_WITH_AES_256_GCM_SHA384
-//#define CIPHER_ID TLS_ECDH_RSA_WITH_AES_128_GCM_SHA256 // SSL_ALERT_HANDSHAKE_FAILURE
-//#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 *** select this?
-//#define CIPHER_ID TLS_DH_anon_WITH_AES_256_CBC_SHA // SSL_ALERT_HANDSHAKE_FAILURE
-//^^^^^^^^^^^^^^^^^^^^^^^ (tested b/c this one doesn't req server certs... no luck)
-//test TLS_RSA_WITH_AES_128_CBC_SHA, in tls 1.2 it's mandated to be always supported
-
-struct record_hdr {
- uint8_t type;
- uint8_t proto_maj, proto_min;
- uint8_t len16_hi, len16_lo;
-};
-
-typedef struct tls_state {
- int fd;
-
- psRsaKey_t server_rsa_pub_key;
-
- // RFC 5246
- // |6.2.1. Fragmentation
+#define TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA 0xC035
+#define TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA 0xC036
+#define TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA256 0xC037
+#define TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA384 0xC038
+
+/* From http://wiki.mozilla.org/Security/Server_Side_TLS */
+/* and 'openssl ciphers -V -stdname' */
+#define TLS_RSA_WITH_AES_128_CCM 0xC09C /*TLSv1.2 Kx=RSA Au=RSA Enc=AESCCM(128) Mac=AEAD */
+#define TLS_RSA_WITH_AES_256_CCM 0xC09D /*TLSv1.2 Kx=RSA Au=RSA Enc=AESCCM(256) Mac=AEAD */
+#define TLS_DHE_RSA_WITH_AES_128_CCM 0xC09E /*TLSv1.2 Kx=DH Au=RSA Enc=AESCCM(128) Mac=AEAD */
+#define TLS_DHE_RSA_WITH_AES_256_CCM 0xC09F /*TLSv1.2 Kx=DH Au=RSA Enc=AESCCM(256) Mac=AEAD */
+#define TLS_RSA_WITH_AES_128_CCM_8 0xC0A0 /*TLSv1.2 Kx=RSA Au=RSA Enc=AESCCM8(128) Mac=AEAD */
+#define TLS_RSA_WITH_AES_256_CCM_8 0xC0A1 /*TLSv1.2 Kx=RSA Au=RSA Enc=AESCCM8(256) Mac=AEAD */
+#define TLS_DHE_RSA_WITH_AES_128_CCM_8 0xC0A2 /*TLSv1.2 Kx=DH Au=RSA Enc=AESCCM8(128) Mac=AEAD */
+#define TLS_DHE_RSA_WITH_AES_256_CCM_8 0xC0A3 /*TLSv1.2 Kx=DH Au=RSA Enc=AESCCM8(256) Mac=AEAD */
+#define TLS_ECDHE_ECDSA_WITH_AES_128_CCM 0xC0AC /*TLSv1.2 Kx=ECDH Au=ECDSA Enc=AESCCM(128) Mac=AEAD */
+#define TLS_ECDHE_ECDSA_WITH_AES_256_CCM 0xC0AD /*TLSv1.2 Kx=ECDH Au=ECDSA Enc=AESCCM(256) Mac=AEAD */
+#define TLS_ECDHE_ECDSA_WITH_AES_128_CCM_8 0xC0AE /*TLSv1.2 Kx=ECDH Au=ECDSA Enc=AESCCM8(128) Mac=AEAD */
+#define TLS_ECDHE_ECDSA_WITH_AES_256_CCM_8 0xC0AF /*TLSv1.2 Kx=ECDH Au=ECDSA Enc=AESCCM8(256) Mac=AEAD */
+#define TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256 0xCCA8 /*TLSv1.2 Kx=ECDH Au=RSA Enc=CHACHA20/POLY1305(256) Mac=AEAD */
+#define TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256 0xCCA9 /*TLSv1.2 Kx=ECDH Au=ECDSA Enc=CHACHA20/POLY1305(256) Mac=AEAD */
+#define TLS_DHE_RSA_WITH_CHACHA20_POLY1305_SHA256 0xCCAA /*TLSv1.2 Kx=DH Au=RSA Enc=CHACHA20/POLY1305(256) Mac=AEAD */
+
+#define TLS_AES_128_GCM_SHA256 0x1301 /*TLSv1.3 Kx=any Au=any Enc=AESGCM(128) Mac=AEAD */
+#define TLS_AES_256_GCM_SHA384 0x1302 /*TLSv1.3 Kx=any Au=any Enc=AESGCM(256) Mac=AEAD */
+#define TLS_CHACHA20_POLY1305_SHA256 0x1303 /*TLSv1.3 Kx=any Au=any Enc=CHACHA20/POLY1305(256) Mac=AEAD */
+#define TLS_AES_128_CCM_SHA256 0x1304 /*TLSv1.3 Kx=any Au=any Enc=AESCCM(128) Mac=AEAD */
+
+/* Might go to libbb.h */
+#define TLS_MAX_CRYPTBLOCK_SIZE 16
+#define TLS_MAX_OUTBUF (1 << 14)
+
+enum {
+ SHA_INSIZE = 64,
+ SHA1_OUTSIZE = 20,
+ SHA256_OUTSIZE = 32,
+
+ AES128_KEYSIZE = 16,
+ AES256_KEYSIZE = 32,
+
+ RSA_PREMASTER_SIZE = 48,
+
+ RECHDR_LEN = 5,
+
+ /* 8 = 3+5. 3 extra bytes result in record data being 32-bit aligned */
+ OUTBUF_PFX = 8 + AES_BLOCK_SIZE, /* header + IV */
+ OUTBUF_SFX = TLS_MAX_MAC_SIZE + TLS_MAX_CRYPTBLOCK_SIZE, /* MAC + padding */
+
+ // RFC 5246:
+ // | 6.2.1. Fragmentation
// | The record layer fragments information blocks into TLSPlaintext
// | records carrying data in chunks of 2^14 bytes or less. Client
// | message boundaries are not preserved in the record layer (i.e.,
// | length
// | The length (in bytes) of the following TLSCompressed.fragment.
// | The length MUST NOT exceed 2^14 + 1024.
- //
- // Since our buffer also contains 5-byte headers, make it a bit bigger:
- int insize;
- int tail;
- uint8_t inbuf[18*1024];
-} tls_state_t;
+ // |...
+ // | 6.2.3. Record Payload Protection
+ // | The encryption and MAC functions translate a TLSCompressed
+ // | structure into a TLSCiphertext. The decryption functions reverse
+ // | the process. The MAC of the record also includes a sequence
+ // | number so that missing, extra, or repeated messages are
+ // | detectable.
+ // |...
+ // | length
+ // | The length (in bytes) of the following TLSCiphertext.fragment.
+ // | The length MUST NOT exceed 2^14 + 2048.
+ MAX_INBUF = RECHDR_LEN + (1 << 14) + 2048,
+
+ /* Bits for tls->flags */
+ NEED_EC_KEY = 1 << 0,
+ 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 ALLOW_RSA_NULL_SHA256=1)
+ ENCRYPT_ON_WRITE = 1 << 5,
+};
+
+struct record_hdr {
+ uint8_t type;
+ uint8_t proto_maj, proto_min;
+ uint8_t len16_hi, len16_lo;
+};
+
+struct tls_handshake_data {
+ /* In bbox, md5/sha1/sha256 ctx's are the same structure */
+ md5sha_ctx_t handshake_hash_ctx;
-void tls_get_random(void *buf, unsigned len)
+ uint8_t client_and_server_rand32[2 * 32];
+ uint8_t master_secret[48];
+
+//TODO: store just the DER key here, parse/use/delete it when sending client key
+//this way it will stay key type agnostic here.
+ psRsaKey_t server_rsa_pub_key;
+ uint8_t ecc_pub_key32[32];
+
+/* HANDSHAKE HASH: */
+ //unsigned saved_client_hello_size;
+ //uint8_t saved_client_hello[1];
+};
+
+
+static unsigned get24be(const uint8_t *p)
{
- if (len != open_read_close("/dev/urandom", buf, len))
- xfunc_die();
+ return 0x100*(0x100*p[0] + p[1]) + p[2];
}
-static
-tls_state_t *new_tls_state(void)
+#if TLS_DEBUG
+/* Nondestructively see the current hash value */
+# if TLS_DEBUG_HASH
+static unsigned sha_peek(md5sha_ctx_t *ctx, void *buffer)
{
- tls_state_t *tls = xzalloc(sizeof(*tls));
- tls->fd = -1;
- return tls;
+ md5sha_ctx_t ctx_copy = *ctx; /* struct copy */
+ return sha_end(&ctx_copy, buffer);
}
+# endif
-static unsigned get24be(const uint8_t *p)
+static void dump_hex(const char *fmt, const void *vp, int len)
{
- return 0x100*(0x100*p[0] + p[1]) + p[2];
+ char hexbuf[32 * 1024 + 4];
+ const uint8_t *p = vp;
+
+ bin2hex(hexbuf, (void*)p, len)[0] = '\0';
+ dbg(fmt, hexbuf);
}
-static void dump(const void *vp, int len)
+static void dump_tls_record(const void *vp, int len)
{
- char hexbuf[32 * 1024 + 4];
const uint8_t *p = vp;
while (len > 0) {
unsigned xhdr_len;
- if (len < 5) {
- bin2hex(hexbuf, (void*)p, len)[0] = '\0';
- dbg("< |%s|\n", hexbuf);
+ if (len < RECHDR_LEN) {
+ dump_hex("< |%s|\n", p, len);
return;
}
xhdr_len = 0x100*p[3] + p[4];
dbg("< hdr_type:%u ver:%u.%u len:%u", p[0], p[1], p[2], xhdr_len);
- p += 5;
- len -= 5;
- if (len >= 4 && p[-5] == RECORD_TYPE_HANDSHAKE) {
+ p += RECHDR_LEN;
+ len -= RECHDR_LEN;
+ if (len >= 4 && p[-RECHDR_LEN] == RECORD_TYPE_HANDSHAKE) {
unsigned len24 = get24be(p + 1);
dbg(" type:%u len24:%u", p[0], len24);
}
if (xhdr_len > len)
xhdr_len = len;
- bin2hex(hexbuf, (void*)p, xhdr_len)[0] = '\0';
- dbg(" |%s|\n", hexbuf);
+ dump_hex(" |%s|\n", p, xhdr_len);
p += xhdr_len;
len -= xhdr_len;
}
}
+#else
+# define dump_hex(...) ((void)0)
+# define dump_tls_record(...) ((void)0)
+#endif
+
+void FAST_FUNC tls_get_random(void *buf, unsigned len)
+{
+ if (len != open_read_close("/dev/urandom", buf, len))
+ xfunc_die();
+}
-static void tls_error_die(tls_state_t *tls)
+static void xorbuf3(void *dst, const void *src1, const void *src2, unsigned count)
{
- dump(tls->inbuf, tls->insize + tls->tail);
+ uint8_t *d = dst;
+ const uint8_t *s1 = src1;
+ const uint8_t* s2 = src2;
+ while (count--)
+ *d++ = *s1++ ^ *s2++;
+}
+
+void FAST_FUNC xorbuf(void *dst, const void *src, unsigned count)
+{
+ xorbuf3(dst, dst, src, count);
+}
+
+void FAST_FUNC xorbuf_aligned_AES_BLOCK_SIZE(void *dst, const void *src)
+{
+ unsigned long *d = dst;
+ const unsigned long *s = src;
+ d[0] ^= s[0];
+#if ULONG_MAX <= 0xffffffffffffffff
+ d[1] ^= s[1];
+ #if ULONG_MAX == 0xffffffff
+ d[2] ^= s[2];
+ d[3] ^= s[3];
+ #endif
+#endif
+}
+
+#if !TLS_DEBUG_HASH
+# define hash_handshake(tls, fmt, buffer, len) \
+ hash_handshake(tls, buffer, len)
+#endif
+static void hash_handshake(tls_state_t *tls, const char *fmt, const void *buffer, unsigned len)
+{
+ md5sha_hash(&tls->hsd->handshake_hash_ctx, buffer, len);
+#if TLS_DEBUG_HASH
+ {
+ uint8_t h[TLS_MAX_MAC_SIZE];
+ dump_hex(fmt, buffer, len);
+ dbg(" (%u bytes) ", (int)len);
+ len = sha_peek(&tls->hsd->handshake_hash_ctx, h);
+ if (ENABLE_FEATURE_TLS_SHA1 && len == SHA1_OUTSIZE)
+ dump_hex("sha1:%s\n", h, len);
+ else
+ if (len == SHA256_OUTSIZE)
+ dump_hex("sha256:%s\n", h, len);
+ else
+ dump_hex("sha???:%s\n", h, len);
+ }
+#endif
+}
+
+#if !ENABLE_FEATURE_TLS_SHA1
+# define TLS_MAC_SIZE(tls) SHA256_OUTSIZE
+#else
+# define TLS_MAC_SIZE(tls) (tls)->MAC_size
+#endif
+
+// RFC 2104:
+// HMAC(key, text) based on a hash H (say, sha256) is:
+// ipad = [0x36 x INSIZE]
+// opad = [0x5c x INSIZE]
+// HMAC(key, text) = H((key XOR opad) + H((key XOR ipad) + text))
+//
+// H(key XOR opad) and H(key XOR ipad) can be precomputed
+// if we often need HMAC hmac with the same key.
+//
+// text is often given in disjoint pieces.
+typedef struct hmac_precomputed {
+ md5sha_ctx_t hashed_key_xor_ipad;
+ md5sha_ctx_t hashed_key_xor_opad;
+} hmac_precomputed_t;
+
+typedef void md5sha_begin_func(md5sha_ctx_t *ctx) FAST_FUNC;
+#if !ENABLE_FEATURE_TLS_SHA1
+#define hmac_begin(pre,key,key_size,begin) \
+ hmac_begin(pre,key,key_size)
+#define begin sha256_begin
+#endif
+static void hmac_begin(hmac_precomputed_t *pre, uint8_t *key, unsigned key_size, md5sha_begin_func *begin)
+{
+ uint8_t key_xor_ipad[SHA_INSIZE];
+ uint8_t key_xor_opad[SHA_INSIZE];
+// uint8_t tempkey[SHA1_OUTSIZE < SHA256_OUTSIZE ? SHA256_OUTSIZE : SHA1_OUTSIZE];
+ unsigned i;
+
+ // "The authentication key can be of any length up to INSIZE, the
+ // block length of the hash function. Applications that use keys longer
+ // than INSIZE bytes will first hash the key using H and then use the
+ // resultant OUTSIZE byte string as the actual key to HMAC."
+ if (key_size > SHA_INSIZE) {
+ bb_simple_error_msg_and_die("HMAC key>64"); //does not happen (yet?)
+// md5sha_ctx_t ctx;
+// begin(&ctx);
+// md5sha_hash(&ctx, key, key_size);
+// key_size = sha_end(&ctx, tempkey);
+// //key = tempkey; - right? RIGHT? why does it work without this?
+// // because SHA_INSIZE is 64, but hmac() is always called with
+// // key_size = tls->MAC_size = SHA1/256_OUTSIZE (20 or 32),
+// // and prf_hmac_sha256() -> hmac_sha256() key sizes are:
+// // - RSA_PREMASTER_SIZE is 48
+// // - CURVE25519_KEYSIZE is 32
+// // - master_secret[] is 48
+ }
+
+ for (i = 0; i < key_size; i++) {
+ key_xor_ipad[i] = key[i] ^ 0x36;
+ key_xor_opad[i] = key[i] ^ 0x5c;
+ }
+ for (; i < SHA_INSIZE; i++) {
+ key_xor_ipad[i] = 0x36;
+ key_xor_opad[i] = 0x5c;
+ }
+
+ begin(&pre->hashed_key_xor_ipad);
+ begin(&pre->hashed_key_xor_opad);
+ md5sha_hash(&pre->hashed_key_xor_ipad, key_xor_ipad, SHA_INSIZE);
+ md5sha_hash(&pre->hashed_key_xor_opad, key_xor_opad, SHA_INSIZE);
+}
+#undef begin
+
+static unsigned hmac_sha_precomputed_v(
+ hmac_precomputed_t *pre,
+ uint8_t *out,
+ va_list va)
+{
+ uint8_t *text;
+ unsigned len;
+
+ /* pre->hashed_key_xor_ipad contains unclosed "H((key XOR ipad) +" state */
+ /* pre->hashed_key_xor_opad contains unclosed "H((key XOR opad) +" state */
+
+ /* calculate out = H((key XOR ipad) + text) */
+ while ((text = va_arg(va, uint8_t*)) != NULL) {
+ unsigned text_size = va_arg(va, unsigned);
+ md5sha_hash(&pre->hashed_key_xor_ipad, text, text_size);
+ }
+ len = sha_end(&pre->hashed_key_xor_ipad, out);
+
+ /* out = H((key XOR opad) + out) */
+ md5sha_hash(&pre->hashed_key_xor_opad, out, len);
+ return sha_end(&pre->hashed_key_xor_opad, out);
+}
+
+static unsigned hmac_sha_precomputed(hmac_precomputed_t *pre_init, uint8_t *out, ...)
+{
+ hmac_precomputed_t pre;
+ va_list va;
+ unsigned len;
+
+ va_start(va, out);
+ pre = *pre_init; /* struct copy */
+ len = hmac_sha_precomputed_v(&pre, out, va);
+ va_end(va);
+ return len;
+}
+
+#if !ENABLE_FEATURE_TLS_SHA1
+#define hmac(tls,out,key,key_size,...) \
+ hmac(out,key,key_size, __VA_ARGS__)
+#endif
+static unsigned hmac(tls_state_t *tls, uint8_t *out, uint8_t *key, unsigned key_size, ...)
+{
+ hmac_precomputed_t pre;
+ va_list va;
+ unsigned len;
+
+ va_start(va, key_size);
+
+ hmac_begin(&pre, key, key_size,
+ (ENABLE_FEATURE_TLS_SHA1 && tls->MAC_size == SHA1_OUTSIZE)
+ ? sha1_begin
+ : sha256_begin
+ );
+ len = hmac_sha_precomputed_v(&pre, out, va);
+
+ va_end(va);
+ return len;
+}
+
+// RFC 5246:
+// 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.
+// ^^^^^^^^^^^^^ IMPORTANT!
+// PRF uses sha256 regardless of cipher for all ciphers
+// defined by RFC 5246. It's not sha1 for AES_128_CBC_SHA!
+// However, for _SHA384 ciphers, it's sha384. See RFC 5288,5289.
+//...
+// 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(1) = HMAC_hash(secret, A(0)) = HMAC_hash(secret, 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.
+//
+// RFC 5288:
+// For cipher suites ending with _SHA256, the PRF is the TLS PRF
+// with SHA-256 as the hash function.
+// For cipher suites ending with _SHA384, the PRF is the TLS PRF
+// with SHA-384 as the hash function.
+static void prf_hmac_sha256(/*tls_state_t *tls,*/
+ uint8_t *outbuf, unsigned outbuf_size,
+ uint8_t *secret, unsigned secret_size,
+ const char *label,
+ uint8_t *seed, unsigned seed_size)
+{
+ hmac_precomputed_t pre;
+ uint8_t a[TLS_MAX_MAC_SIZE];
+ uint8_t *out_p = outbuf;
+ unsigned label_size = strlen(label);
+ unsigned MAC_size = SHA256_OUTSIZE;
+
+ /* In P_hash() calculation, "seed" is "label + seed": */
+#define SEED label, label_size, seed, seed_size
+#define A a, MAC_size
+
+ hmac_begin(&pre, secret, secret_size, sha256_begin);
+
+ /* A(1) = HMAC_hash(secret, seed) */
+ hmac_sha_precomputed(&pre, a, SEED, NULL);
+
+ for (;;) {
+ /* HMAC_hash(secret, A(1) + seed) */
+ if (outbuf_size <= MAC_size) {
+ /* Last, possibly incomplete, block */
+ /* (use a[] as temp buffer) */
+ hmac_sha_precomputed(&pre, a, A, SEED, NULL);
+ memcpy(out_p, a, outbuf_size);
+ return;
+ }
+ /* Not last block. Store directly to result buffer */
+ hmac_sha_precomputed(&pre, out_p, A, SEED, NULL);
+ out_p += MAC_size;
+ outbuf_size -= MAC_size;
+ /* A(2) = HMAC_hash(secret, A(1)) */
+ hmac_sha_precomputed(&pre, a, A, NULL);
+ }
+#undef A
+#undef SECRET
+#undef SEED
+}
+
+static void bad_record_die(tls_state_t *tls, const char *expected, int len)
+{
+ bb_error_msg("got bad TLS record (len:%d) while expecting %s", len, expected);
+ if (len > 0) {
+ uint8_t *p = tls->inbuf;
+ if (len > 99)
+ len = 99; /* don't flood, a few lines should be enough */
+ do {
+ fprintf(stderr, " %02x", *p++);
+ len--;
+ } while (len != 0);
+ fputc('\n', stderr);
+ }
xfunc_die();
}
-static int xread_tls_block(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("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)
+{
+ if (tls->buffered_size == 0) {
+ free(tls->inbuf);
+ tls->inbuf_size = 0;
+ tls->inbuf = NULL;
+ }
+}
+#endif
+
+static void tls_free_outbuf(tls_state_t *tls)
+{
+ free(tls->outbuf);
+ tls->outbuf_size = 0;
+ tls->outbuf = NULL;
+}
+
+static void *tls_get_outbuf(tls_state_t *tls, int len)
+{
+ if (len > TLS_MAX_OUTBUF)
+ xfunc_die();
+ len += OUTBUF_PFX + OUTBUF_SFX;
+ if (tls->outbuf_size < len) {
+ tls->outbuf_size = len;
+ tls->outbuf = xrealloc(tls->outbuf, len);
+ }
+ return tls->outbuf + OUTBUF_PFX;
+}
+
+static void *tls_get_zeroed_outbuf(tls_state_t *tls, int len)
+{
+ void *record = tls_get_outbuf(tls, len);
+ memset(record, 0, len);
+ return record;
+}
+
+static void xwrite_encrypted_and_hmac_signed(tls_state_t *tls, unsigned size, unsigned type)
{
+ uint8_t *buf = tls->outbuf + OUTBUF_PFX;
struct record_hdr *xhdr;
- int len;
+ uint8_t padding_length;
+
+ xhdr = (void*)(buf - RECHDR_LEN);
+ 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 */
+ }
+
+ xhdr->type = type;
+ xhdr->proto_maj = TLS_MAJ;
+ xhdr->proto_min = TLS_MIN;
+ /* fake unencrypted record len for MAC calculation */
+ xhdr->len16_hi = size >> 8;
+ xhdr->len16_lo = size & 0xff;
+
+ /* Calculate MAC signature */
+ hmac(tls, buf + size, /* result */
+ tls->client_write_MAC_key, TLS_MAC_SIZE(tls),
+ &tls->write_seq64_be, sizeof(tls->write_seq64_be),
+ xhdr, RECHDR_LEN,
+ buf, size,
+ NULL
+ );
+ tls->write_seq64_be = SWAP_BE64(1 + SWAP_BE64(tls->write_seq64_be));
+
+ size += TLS_MAC_SIZE(tls);
+
+ // RFC 5246:
+ // 6.2.3.1. Null or Standard Stream Cipher
+ //
+ // Stream ciphers (including BulkCipherAlgorithm.null; see Appendix A.6)
+ // convert TLSCompressed.fragment structures to and from stream
+ // TLSCiphertext.fragment structures.
+ //
+ // stream-ciphered struct {
+ // opaque content[TLSCompressed.length];
+ // opaque MAC[SecurityParameters.mac_length];
+ // } GenericStreamCipher;
+ //
+ // The MAC is generated as:
+ // MAC(MAC_write_key, seq_num +
+ // TLSCompressed.type +
+ // TLSCompressed.version +
+ // TLSCompressed.length +
+ // TLSCompressed.fragment);
+ // where "+" denotes concatenation.
+ // seq_num
+ // The sequence number for this record.
+ // MAC
+ // The MAC algorithm specified by SecurityParameters.mac_algorithm.
+ //
+ // Note that the MAC is computed before encryption. The stream cipher
+ // encrypts the entire block, including the MAC.
+ //...
+ // Appendix C. Cipher Suite Definitions
+ //...
+ // MAC Algorithm mac_length mac_key_length
+ // -------- ----------- ---------- --------------
+ // SHA HMAC-SHA1 20 20
+ // SHA256 HMAC-SHA256 32 32
+ if (ALLOW_RSA_NULL_SHA256
+ && tls->cipher_id == TLS_RSA_WITH_NULL_SHA256
+ ) {
+ /* No encryption, only signing */
+ xhdr->len16_hi = size >> 8;
+ xhdr->len16_lo = size & 0xff;
+ dump_raw_out(">> %s\n", xhdr, RECHDR_LEN + size);
+ xwrite(tls->ofd, xhdr, RECHDR_LEN + size);
+ dbg("wrote %u bytes (NULL crypt, SHA256 hash)\n", size);
+ return;
+ }
+
+ // 6.2.3.2. CBC Block Cipher
+ // For block ciphers (such as 3DES or AES), the encryption and MAC
+ // functions convert TLSCompressed.fragment structures to and from block
+ // TLSCiphertext.fragment structures.
+ // struct {
+ // opaque IV[SecurityParameters.record_iv_length];
+ // block-ciphered struct {
+ // opaque content[TLSCompressed.length];
+ // opaque MAC[SecurityParameters.mac_length];
+ // uint8 padding[GenericBlockCipher.padding_length];
+ // uint8 padding_length;
+ // };
+ // } GenericBlockCipher;
+ //...
+ // IV
+ // The Initialization Vector (IV) SHOULD be chosen at random, and
+ // MUST be unpredictable. Note that in versions of TLS prior to 1.1,
+ // there was no IV field (...). For block ciphers, the IV length is
+ // of length SecurityParameters.record_iv_length, which is equal to the
+ // SecurityParameters.block_size.
+ // padding
+ // Padding that is added to force the length of the plaintext to be
+ // an integral multiple of the block cipher's block length.
+ // padding_length
+ // The padding length MUST be such that the total size of the
+ // GenericBlockCipher structure is a multiple of the cipher's block
+ // length. Legal values range from zero to 255, inclusive.
+ //...
+ // Appendix C. Cipher Suite Definitions
+ //...
+ // Key IV Block
+ // Cipher Type Material Size Size
+ // ------------ ------ -------- ---- -----
+ // AES_128_CBC Block 16 16 16
+ // AES_256_CBC Block 32 16 16
+
+ tls_get_random(buf - AES_BLOCK_SIZE, AES_BLOCK_SIZE); /* IV */
+ dbg("before crypt: 5 hdr + %u data + %u hash bytes\n",
+ size - TLS_MAC_SIZE(tls), TLS_MAC_SIZE(tls));
+
+ /* Fill IV and padding in outbuf */
+ // RFC is talking nonsense:
+ // "Padding that is added to force the length of the plaintext to be
+ // an integral multiple of the block cipher's block length."
+ // WRONG. _padding+padding_length_, not just _padding_,
+ // pads the data.
+ // IOW: padding_length is the last byte of padding[] array,
+ // contrary to what RFC depicts.
+ //
+ // What actually happens is that there is always padding.
+ // If you need one byte to reach BLOCKSIZE, this byte is 0x00.
+ // If you need two bytes, they are both 0x01.
+ // If you need three, they are 0x02,0x02,0x02. And so on.
+ // If you need no bytes to reach BLOCKSIZE, you have to pad a full
+ // BLOCKSIZE with bytes of value (BLOCKSIZE-1).
+ // It's ok to have more than minimum padding, but we do minimum.
+ padding_length = (~size) & (AES_BLOCK_SIZE - 1);
+ do {
+ buf[size++] = padding_length; /* padding */
+ } while ((size & (AES_BLOCK_SIZE - 1)) != 0);
+
+ /* Encrypt content+MAC+padding in place */
+ aes_cbc_encrypt(
+ &tls->aes_encrypt, /* selects 128/256 */
+ buf - AES_BLOCK_SIZE, /* IV */
+ buf, size, /* plaintext */
+ buf /* ciphertext */
+ );
+
+ /* Write out */
+ dbg("writing 5 + %u IV + %u encrypted bytes, padding_length:0x%02x\n",
+ AES_BLOCK_SIZE, size, padding_length);
+ size += AES_BLOCK_SIZE; /* + IV */
+ xhdr->len16_hi = size >> 8;
+ xhdr->len16_lo = size & 0xff;
+ dump_raw_out(">> %s\n", xhdr, RECHDR_LEN + size);
+ xwrite(tls->ofd, xhdr, RECHDR_LEN + size);
+ dbg("wrote %u bytes\n", (int)RECHDR_LEN + size);
+}
+
+/* Example how GCM encryption combines nonce, aad, input and generates
+ * "header | exp_nonce | encrypted output | tag":
+ * nonce:0d 6a 26 31 00 00 00 00 00 00 00 01 (implicit 4 bytes (derived from master secret), then explicit 8 bytes)
+ * aad: 00 00 00 00 00 00 00 01 17 03 03 00 1c
+ * in: 47 45 54 20 2f 69 6e 64 65 78 2e 68 74 6d 6c 20 48 54 54 50 2f 31 2e 30 0d 0a 0d 0a "GET /index.html HTTP/1.0\r\n\r\n" (0x1c bytes)
+ * out: f7 8a b2 8f 78 0e f6 d5 76 17 2e b5 6d 46 59 56 8b 46 9f 0b d9 2c 35 28 13 66 19 be
+ * tag: c2 86 ce 4a 50 4a d0 aa 50 b3 76 5c 49 2a 3f 33
+ * sent: 17 03 03 00 34|00 00 00 00 00 00 00 01|f7 8a b2 8f 78 0e f6 d5 76 17 2e b5 6d 46 59 56 8b 46 9f 0b d9 2c 35 28 13 66 19 be|c2 86 ce 4a 50 4a d0 aa 50 b3 76 5c 49 2a 3f 33
+ * .............................................^^ buf points here
+ */
+static void xwrite_encrypted_aesgcm(tls_state_t *tls, unsigned size, unsigned type)
+{
+#define COUNTER(v) (*(uint32_t*)(v + 12))
+
+ uint8_t aad[13 + 3] ALIGNED_long; /* +3 creates [16] buffer, simplifying GHASH() */
+ uint8_t nonce[12 + 4] ALIGNED_long; /* +4 creates space for AES block counter */
+ uint8_t scratch[AES_BLOCK_SIZE] ALIGNED_long; //[16]
+ uint8_t authtag[AES_BLOCK_SIZE] ALIGNED_long; //[16]
+ uint8_t *buf;
+ struct record_hdr *xhdr;
+ unsigned remaining;
+ unsigned cnt;
+ uint64_t t64;
+
+ buf = tls->outbuf + OUTBUF_PFX; /* see above for the byte it points to */
+ dump_hex("xwrite_encrypted_aesgcm plaintext:%s\n", buf, size);
+
+ xhdr = (void*)(buf - 8 - RECHDR_LEN);
+ xhdr->type = type; /* do it here so that "type" param no longer used */
+
+ aad[8] = type;
+ aad[9] = TLS_MAJ;
+ aad[10] = TLS_MIN;
+ aad[11] = size >> 8;
+ /* set aad[12], and clear aad[13..15] */
+ COUNTER(aad) = SWAP_LE32(size & 0xff);
+
+ memcpy(nonce, tls->client_write_IV, 4);
+ t64 = tls->write_seq64_be;
+ move_to_unaligned64(nonce + 4, t64);
+ move_to_unaligned64(aad, t64);
+ move_to_unaligned64(buf - 8, t64);
+ /* seq64 is not used later in this func, can increment here */
+ tls->write_seq64_be = SWAP_BE64(1 + SWAP_BE64(t64));
+
+ cnt = 1;
+ remaining = size;
+ while (remaining != 0) {
+ unsigned n;
+
+ cnt++;
+ COUNTER(nonce) = htonl(cnt); /* yes, first cnt here is 2 (!) */
+ aes_encrypt_one_block(&tls->aes_encrypt, nonce, scratch);
+ n = remaining > AES_BLOCK_SIZE ? AES_BLOCK_SIZE : remaining;
+ xorbuf(buf, scratch, n);
+ buf += n;
+ remaining -= n;
+ }
+
+ aesgcm_GHASH(tls->H, aad, /*sizeof(aad),*/ tls->outbuf + OUTBUF_PFX, size, authtag /*, sizeof(authtag)*/);
+ COUNTER(nonce) = htonl(1);
+ aes_encrypt_one_block(&tls->aes_encrypt, nonce, scratch);
+ xorbuf_aligned_AES_BLOCK_SIZE(authtag, scratch);
+
+ memcpy(buf, authtag, sizeof(authtag));
+
+ /* Write out */
+ xhdr = (void*)(tls->outbuf + OUTBUF_PFX - 8 - RECHDR_LEN);
+ size += 8 + sizeof(authtag);
+ /*xhdr->type = type; - already is */
+ xhdr->proto_maj = TLS_MAJ;
+ xhdr->proto_min = TLS_MIN;
+ xhdr->len16_hi = size >> 8;
+ xhdr->len16_lo = size & 0xff;
+ size += RECHDR_LEN;
+ dump_raw_out(">> %s\n", xhdr, size);
+ xwrite(tls->ofd, xhdr, size);
+ dbg("wrote %u bytes\n", size);
+#undef COUNTER
+}
+
+static void xwrite_encrypted(tls_state_t *tls, unsigned size, unsigned type)
+{
+ if (!(tls->flags & ENCRYPTION_AESGCM)) {
+ xwrite_encrypted_and_hmac_signed(tls, size, type);
+ return;
+ }
+ xwrite_encrypted_aesgcm(tls, size, type);
+}
+
+static void xwrite_handshake_record(tls_state_t *tls, unsigned size)
+{
+ uint8_t *buf = tls->outbuf + OUTBUF_PFX;
+ struct record_hdr *xhdr = (void*)(buf - RECHDR_LEN);
+
+ xhdr->type = RECORD_TYPE_HANDSHAKE;
+ xhdr->proto_maj = TLS_MAJ;
+ xhdr->proto_min = TLS_MIN;
+ xhdr->len16_hi = size >> 8;
+ xhdr->len16_lo = size & 0xff;
+ dump_raw_out(">> %s\n", xhdr, RECHDR_LEN + size);
+ xwrite(tls->ofd, xhdr, RECHDR_LEN + size);
+ dbg("wrote %u bytes\n", (int)RECHDR_LEN + size);
+}
+
+static void xwrite_and_update_handshake_hash(tls_state_t *tls, unsigned size)
+{
+ if (!(tls->flags & ENCRYPT_ON_WRITE)) {
+ uint8_t *buf;
+
+ xwrite_handshake_record(tls, size);
+ /* Handshake hash does not include record headers */
+ buf = tls->outbuf + OUTBUF_PFX;
+ hash_handshake(tls, ">> hash:%s", buf, size);
+ return;
+ }
+ xwrite_encrypted(tls, size, RECORD_TYPE_HANDSHAKE);
+}
+
+static int tls_has_buffered_record(tls_state_t *tls)
+{
+ int buffered = tls->buffered_size;
+ struct record_hdr *xhdr;
+ int rec_size;
+
+ if (buffered < RECHDR_LEN)
+ return 0;
+ xhdr = (void*)(tls->inbuf + tls->ofs_to_buffered);
+ rec_size = RECHDR_LEN + (0x100 * xhdr->len16_hi + xhdr->len16_lo);
+ if (buffered < rec_size)
+ return 0;
+ return rec_size;
+}
+
+static const char *alert_text(int code)
+{
+ switch (code) {
+ case 20: return "bad MAC";
+ case 50: return "decode error";
+ case 51: return "decrypt error";
+ case 40: return "handshake failure";
+ case 112: return "unrecognized name";
+ }
+ return itoa(code);
+}
+
+static void tls_aesgcm_decrypt(tls_state_t *tls, uint8_t *buf, int size)
+{
+#define COUNTER(v) (*(uint32_t*)(v + 12))
+
+ //uint8_t aad[13 + 3] ALIGNED_long; /* +3 creates [16] buffer, simplifying GHASH() */
+ uint8_t nonce[12 + 4] ALIGNED_long; /* +4 creates space for AES block counter */
+ uint8_t scratch[AES_BLOCK_SIZE] ALIGNED_long; //[16]
+ //uint8_t authtag[AES_BLOCK_SIZE] ALIGNED_long; //[16]
+ unsigned remaining;
+ unsigned cnt;
+
+ //memcpy(aad, buf, 8);
+ //aad[8] = type;
+ //aad[9] = TLS_MAJ;
+ //aad[10] = TLS_MIN;
+ //aad[11] = size >> 8;
+ ///* set aad[12], and clear aad[13..15] */
+ //COUNTER(aad) = SWAP_LE32(size & 0xff);
+
+ memcpy(nonce, tls->server_write_IV, 4);
+ memcpy(nonce + 4, buf, 8);
+
+ cnt = 1;
+ remaining = size;
+ while (remaining != 0) {
+ unsigned n;
+
+ cnt++;
+ COUNTER(nonce) = htonl(cnt); /* yes, first cnt here is 2 (!) */
+ aes_encrypt_one_block(&tls->aes_decrypt, nonce, scratch);
+ n = remaining > AES_BLOCK_SIZE ? AES_BLOCK_SIZE : remaining;
+ xorbuf3(buf, scratch, buf + 8, n);
+ buf += n;
+ remaining -= n;
+ }
+
+ //aesgcm_GHASH(tls->H, aad, tls->inbuf + RECHDR_LEN, size, authtag);
+ //COUNTER(nonce) = htonl(1);
+ //aes_encrypt_one_block(&tls->aes_encrypt, nonce, scratch);
+ //xorbuf_aligned_AES_BLOCK_SIZE(authtag, scratch);
+
+ //memcmp(buf, authtag, sizeof(authtag)) || DIE("HASH DOES NOT MATCH!");
+#undef COUNTER
+}
+
+static int tls_xread_record(tls_state_t *tls, const char *expected)
+{
+ struct record_hdr *xhdr;
+ int sz;
int total;
int target;
- dbg("insize:%u tail:%u\n", tls->insize, tls->tail);
- memmove(tls->inbuf, tls->inbuf + tls->insize, tls->tail);
+ again:
+ dbg("ofs_to_buffered:%u buffered_size:%u\n", tls->ofs_to_buffered, tls->buffered_size);
+ total = tls->buffered_size;
+ if (total != 0) {
+ memmove(tls->inbuf, tls->inbuf + tls->ofs_to_buffered, total);
+ //dbg("<< remaining at %d [%d] ", tls->ofs_to_buffered, total);
+ //dump_raw_in("<< %s\n", tls->inbuf, total);
+ }
errno = 0;
- total = tls->tail;
- target = sizeof(tls->inbuf);
+ target = MAX_INBUF;
for (;;) {
- if (total >= sizeof(*xhdr) && target == sizeof(tls->inbuf)) {
+ int rem;
+
+ if (total >= RECHDR_LEN && target == MAX_INBUF) {
xhdr = (void*)tls->inbuf;
- target = sizeof(*xhdr) + (0x100 * xhdr->len16_hi + xhdr->len16_lo);
- if (target >= sizeof(tls->inbuf)) {
- /* malformed input (too long): yell and die */
- tls->tail = 0;
- tls->insize = total;
- tls_error_die(tls);
+ target = RECHDR_LEN + (0x100 * xhdr->len16_hi + xhdr->len16_lo);
+
+ if (target > MAX_INBUF /* malformed input (too long) */
+ || xhdr->proto_maj != TLS_MAJ
+ || xhdr->proto_min != TLS_MIN
+ ) {
+ sz = total < target ? total : target;
+ bad_record_die(tls, expected, sz);
}
- // can also check type/proto_maj/proto_min here
+ dbg("xhdr type:%d ver:%d.%d len:%d\n",
+ xhdr->type, xhdr->proto_maj, xhdr->proto_min,
+ 0x100 * xhdr->len16_hi + xhdr->len16_lo
+ );
}
/* if total >= target, we have a full packet (and possibly more)... */
if (total - target >= 0)
break;
- len = safe_read(tls->fd, tls->inbuf + total, sizeof(tls->inbuf) - total);
- if (len <= 0)
- bb_perror_msg_and_die("short read");
- total += len;
+ /* input buffer is grown only as needed */
+ rem = tls->inbuf_size - total;
+ if (rem == 0) {
+ tls->inbuf_size += MAX_INBUF / 8;
+ if (tls->inbuf_size > MAX_INBUF)
+ tls->inbuf_size = MAX_INBUF;
+ dbg("inbuf_size:%d\n", tls->inbuf_size);
+ rem = tls->inbuf_size - total;
+ tls->inbuf = xrealloc(tls->inbuf, tls->inbuf_size);
+ }
+ sz = safe_read(tls->ifd, tls->inbuf + total, rem);
+ if (sz <= 0) {
+ if (sz == 0 && total == 0) {
+ /* "Abrupt" EOF, no TLS shutdown (seen from kernel.org) */
+ dbg("EOF (without TLS shutdown) from peer\n");
+ tls->buffered_size = 0;
+ goto end;
+ }
+ bb_perror_msg_and_die("short read, have only %d", total);
+ }
+ dump_raw_in("<< %s\n", tls->inbuf + total, sz);
+ total += sz;
}
- tls->tail = total - target;
- tls->insize = target;
- target -= sizeof(*xhdr);
- dbg("got block len:%u\n", target);
- return target;
-}
-
-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;
- hello.proto_min = TLS_MIN;
- 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;
- int len;
+ tls->buffered_size = total - target;
+ tls->ofs_to_buffered = target;
+ //dbg("<< stashing at %d [%d] ", tls->ofs_to_buffered, tls->buffered_size);
+ //dump_hex("<< %s\n", tls->inbuf + tls->ofs_to_buffered, tls->buffered_size);
+
+ sz = target - RECHDR_LEN;
+
+ /* Needs to be decrypted? */
+ if (tls->min_encrypted_len_on_read != 0) {
+ if (sz < (int)tls->min_encrypted_len_on_read)
+ bb_error_msg_and_die("bad encrypted len:%u", sz);
+
+ if (tls->flags & ENCRYPTION_AESGCM) {
+ /* AESGCM */
+ uint8_t *p = tls->inbuf + RECHDR_LEN;
+
+ sz -= 8 + AES_BLOCK_SIZE; /* we will overwrite nonce, drop hash */
+ tls_aesgcm_decrypt(tls, p, sz);
+ dbg("encrypted size:%u\n", sz);
+ } else
+ if (tls->min_encrypted_len_on_read > TLS_MAC_SIZE(tls)) {
+ /* AES+SHA */
+ uint8_t *p = tls->inbuf + RECHDR_LEN;
+ int padding_len;
+
+ if (sz & (AES_BLOCK_SIZE-1))
+ bb_error_msg_and_die("bad encrypted len:%u", sz);
+
+ /* Decrypt content+MAC+padding, moving it over IV in the process */
+ sz -= AES_BLOCK_SIZE; /* we will overwrite IV now */
+ aes_cbc_decrypt(
+ &tls->aes_decrypt, /* selects 128/256 */
+ p, /* IV */
+ p + AES_BLOCK_SIZE, sz, /* ciphertext */
+ p /* plaintext */
+ );
+ padding_len = p[sz - 1];
+ dbg("encrypted size:%u type:0x%02x padding_length:0x%02x\n", sz, p[0], padding_len);
+ padding_len++;
+ sz -= TLS_MAC_SIZE(tls) + padding_len; /* drop MAC and padding */
+ } else {
+ /* if nonzero, then it's TLS_RSA_WITH_NULL_SHA256: drop MAC */
+ /* else: no encryption yet on input, subtract zero = NOP */
+ sz -= tls->min_encrypted_len_on_read;
+ }
+ }
+ if (sz < 0)
+ bb_simple_error_msg_and_die("encrypted data too short");
- len = xread_tls_block(tls);
+ //dump_hex("<< %s\n", tls->inbuf, RECHDR_LEN + sz);
- 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);
+ xhdr = (void*)tls->inbuf;
+ if (xhdr->type == RECORD_TYPE_ALERT && sz >= 2) {
+ uint8_t *p = tls->inbuf + RECHDR_LEN;
+ dbg("ALERT size:%d level:%d description:%d\n", sz, p[0], p[1]);
+ if (p[0] == 2) { /* fatal */
+ bb_error_msg_and_die("TLS %s from peer (alert code %d): %s",
+ "error",
+ p[1], alert_text(p[1])
+ );
+ }
+ if (p[0] == 1) { /* warning */
+ if (p[1] == 0) { /* "close_notify" warning: it's EOF */
+ dbg("EOF (TLS encoded) from peer\n");
+ sz = 0;
+ goto end;
+ }
+//This possibly needs to be cached and shown only if
+//a fatal alert follows
+// bb_error_msg("TLS %s from peer (alert code %d): %s",
+// "warning",
+// p[1], alert_text(p[1])
+// );
+ /* discard it, get next record */
+ goto again;
+ }
+ /* p[0] not 1 or 2: not defined in protocol */
+ sz = 0;
+ goto end;
}
- 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
- 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
+
+ /* RFC 5246 is not saying it explicitly, but sha256 hash
+ * in our FINISHED record must include data of incoming packets too!
+ */
+ if (tls->inbuf[0] == RECORD_TYPE_HANDSHAKE
+/* HANDSHAKE HASH: */
+ // && do_we_know_which_hash_to_use /* server_hello() might not know it in the future! */
) {
- tls_error_die(tls);
+ hash_handshake(tls, "<< hash:%s", tls->inbuf + RECHDR_LEN, sz);
}
- dbg("got SERVER_HELLO\n");
+ end:
+ dbg("got block len:%u\n", sz);
+ return sz;
}
+static void binary_to_pstm(pstm_int *pstm_n, uint8_t *bin_ptr, unsigned len)
+{
+ pstm_init_for_read_unsigned_bin(/*pool:*/ NULL, pstm_n, len);
+ pstm_read_unsigned_bin(pstm_n, bin_ptr, len);
+ //return bin_ptr + len;
+}
+
+/*
+ * DER parsing routines
+ */
static unsigned get_der_len(uint8_t **bodyp, uint8_t *der, uint8_t *end)
{
unsigned len, len1;
len = der[1]; /* maybe it's short len */
if (len >= 0x80) {
- /* no */
- if (end - der < (int)(len - 0x7e)) /* need 3 or 4 bytes for 81, 82 */
- xfunc_die();
+ /* no, it's long */
- len1 = der[2];
- if (len == 0x81) {
- /* it's "ii 81 xx" */
- } else if (len == 0x82) {
- /* it's "ii 82 xx yy" */
- len1 = 0x100*len1 + der[3];
- der += 1; /* skip [yy] */
- } else {
+ if (len == 0x80 || end - der < (int)(len - 0x7e)) {
/* 0x80 is "0 bytes of len", invalid DER: must use short len if can */
+ /* need 3 or 4 bytes for 81, 82 */
+ xfunc_die();
+ }
+
+ len1 = der[2]; /* if (len == 0x81) it's "ii 81 xx", fetch xx */
+ if (len > 0x82) {
/* >0x82 is "3+ bytes of len", should not happen realistically */
xfunc_die();
}
+ if (len == 0x82) { /* it's "ii 82 xx yy" */
+ len1 = 0x100*len1 + der[3];
+ der += 1; /* skip [yy] */
+ }
der += 1; /* skip [xx] */
len = len1;
// if (len < 0x80)
{
uint8_t *new_der;
unsigned len = get_der_len(&new_der, der, *endp);
- dbg("entered der @%p:0x%02x len:%u inner_byte @%p:0x%02x\n", der, der[0], len, new_der, new_der[0]);
+ dbg_der("entered der @%p:0x%02x len:%u inner_byte @%p:0x%02x\n", der, der[0], len, new_der, new_der[0]);
/* Move "end" position to cover only this item */
*endp = new_der + len;
return new_der;
unsigned len = get_der_len(&new_der, der, end);
/* Skip body */
new_der += len;
- dbg("skipped der 0x%02x, next byte 0x%02x\n", der[0], new_der[0]);
+ dbg_der("skipped der 0x%02x, next byte 0x%02x\n", der[0], new_der[0]);
return new_der;
}
uint8_t *bin_ptr;
unsigned len = get_der_len(&bin_ptr, der, end);
- dbg("binary bytes:%u, first:0x%02x\n", len, bin_ptr[0]);
- pstm_init_for_read_unsigned_bin(/*pool:*/ NULL, pstm_n, len);
- pstm_read_unsigned_bin(pstm_n, bin_ptr, len);
- //return bin + len;
+ dbg_der("binary bytes:%u, first:0x%02x\n", len, bin_ptr[0]);
+ binary_to_pstm(pstm_n, bin_ptr, len);
}
static void find_key_in_der_cert(tls_state_t *tls, uint8_t *der, int len)
* publicKey (BIT STRING)
*
* We need Certificate.tbsCertificate.subjectPublicKeyInfo.publicKey
+ *
+ * Example of an ECDSA key:
+ * SEQ 0x59 bytes (subjectPublicKeyInfo): 3059
+ * SEQ 0x13 bytes (algorithm): 3013
+ * OID 7 bytes: 0607 2a8648ce3d0201 (OID_ECDSA_KEY_ALG 42.134.72.206.61.2.1)
+ * OID 8 bytes: 0608 2a8648ce3d030107 (OID_EC_prime256v1 42.134.72.206.61.3.1.7)
+ * BITSTRING 0x42 bytes (publicKey): 0342
+ * 0004 53af f65e 50cc 7959 7e29 0171 c75c
+ * 7335 e07d f45b 9750 b797 3a38 aebb 2ac6
+ * 8329 2748 e77e 41cb d482 2ce6 05ec a058
+ * f3ab d561 2f4c d845 9ad3 7252 e3de bd3b
+ * 9012
*/
uint8_t *end = der + len;
/* enter "tbsCertificate" item: [der, end) will be only tbsCert */
der = enter_der_item(der, &end);
+ /*
+ * Skip version field only if it is present. For a v1 certificate, the
+ * version field won't be present since v1 is the default value for the
+ * version field and fields with default values should be omitted (see
+ * RFC 5280 sections 4.1 and 4.1.2.1). If the version field is present
+ * it will have a tag class of 2 (context-specific), bit 6 as 1
+ * (constructed), and a tag number of 0 (see ITU-T X.690 sections 8.1.2
+ * and 8.14).
+ */
+ /* bits 7-6: 10 */
+ /* bit 5: 1 */
+ /* bits 4-0: 00000 */
+ if (der[0] == 0xa0)
+ der = skip_der_item(der, end); /* version */
+
/* skip up to subjectPublicKeyInfo */
- der = skip_der_item(der, end); /* version */
der = skip_der_item(der, end); /* serialNumber */
der = skip_der_item(der, end); /* signatureAlgo */
der = skip_der_item(der, end); /* issuer */
/* enter subjectPublicKeyInfo */
der = enter_der_item(der, &end);
{ /* check subjectPublicKeyInfo.algorithm */
- static const uint8_t expected[] = {
+ static const uint8_t OID_RSA_KEY_ALG[] ALIGN1 = {
0x30,0x0d, // SEQ 13 bytes
- 0x06,0x09, 0x2a,0x86,0x48,0x86,0xf7,0x0d,0x01,0x01,0x01, // OID RSA_KEY_ALG 42.134.72.134.247.13.1.1.1
+ 0x06,0x09, 0x2a,0x86,0x48,0x86,0xf7,0x0d,0x01,0x01,0x01, //OID_RSA_KEY_ALG 42.134.72.134.247.13.1.1.1
//0x05,0x00, // NULL
};
- if (memcmp(der, expected, sizeof(expected)) != 0)
- bb_error_msg_and_die("not RSA key");
+ static const uint8_t OID_ECDSA_KEY_ALG[] ALIGN1 = {
+ 0x30,0x13, // SEQ 0x13 bytes
+ 0x06,0x07, 0x2a,0x86,0x48,0xce,0x3d,0x02,0x01, //OID_ECDSA_KEY_ALG 42.134.72.206.61.2.1
+ //allow any curve code for now...
+ // 0x06,0x08, 0x2a,0x86,0x48,0xce,0x3d,0x03,0x01,0x07, //OID_EC_prime256v1 42.134.72.206.61.3.1.7
+ //RFC 3279:
+ //42.134.72.206.61.3 is ellipticCurve
+ //42.134.72.206.61.3.0 is c-TwoCurve
+ //42.134.72.206.61.3.1 is primeCurve
+ //42.134.72.206.61.3.1.7 is curve_secp256r1
+ };
+ if (memcmp(der, OID_RSA_KEY_ALG, sizeof(OID_RSA_KEY_ALG)) == 0) {
+ dbg("RSA key\n");
+ tls->flags |= GOT_CERT_RSA_KEY_ALG;
+ } else
+ if (memcmp(der, OID_ECDSA_KEY_ALG, sizeof(OID_ECDSA_KEY_ALG)) == 0) {
+ dbg("ECDSA key\n");
+ //UNUSED: tls->flags |= GOT_CERT_ECDSA_KEY_ALG;
+ } else
+ bb_simple_error_msg_and_die("not RSA or ECDSA cert");
}
- /* skip subjectPublicKeyInfo.algorithm */
- der = skip_der_item(der, end);
- /* enter subjectPublicKeyInfo.publicKey */
-// die_if_not_this_der_type(der, end, 0x03); /* must be BITSTRING */
- der = enter_der_item(der, &end);
- /* parse RSA key: */
-//based on getAsnRsaPubKey(), pkcs1ParsePrivBin() is also of note
- dbg("key bytes:%u, first:0x%02x\n", (int)(end - der), der[0]);
- if (end - der < 14) xfunc_die();
- /* example format:
- * ignore bits: 00
- * SEQ 0x018a/394 bytes: 3082018a
- * INTEGER 0x0181/385 bytes (modulus): 02820181 XX...XXX
- * INTEGER 3 bytes (exponent): 0203 010001
+ if (tls->flags & GOT_CERT_RSA_KEY_ALG) {
+ /* parse RSA key: */
+ //based on getAsnRsaPubKey(), pkcs1ParsePrivBin() is also of note
+ /* skip subjectPublicKeyInfo.algorithm */
+ der = skip_der_item(der, end);
+ /* enter subjectPublicKeyInfo.publicKey */
+ //die_if_not_this_der_type(der, end, 0x03); /* must be BITSTRING */
+ der = enter_der_item(der, &end);
+
+ dbg("key bytes:%u, first:0x%02x\n", (int)(end - der), der[0]);
+ if (end - der < 14)
+ xfunc_die();
+ /* example format:
+ * ignore bits: 00
+ * SEQ 0x018a/394 bytes: 3082018a
+ * INTEGER 0x0181/385 bytes (modulus): 02820181 XX...XXX
+ * INTEGER 3 bytes (exponent): 0203 010001
+ */
+ if (*der != 0) /* "ignore bits", should be 0 */
+ xfunc_die();
+ der++;
+ der = enter_der_item(der, &end); /* enter SEQ */
+ /* memset(tls->hsd->server_rsa_pub_key, 0, sizeof(tls->hsd->server_rsa_pub_key)); - already is */
+ der_binary_to_pstm(&tls->hsd->server_rsa_pub_key.N, der, end); /* modulus */
+ der = skip_der_item(der, end);
+ der_binary_to_pstm(&tls->hsd->server_rsa_pub_key.e, der, end); /* exponent */
+ tls->hsd->server_rsa_pub_key.size = pstm_unsigned_bin_size(&tls->hsd->server_rsa_pub_key.N);
+ dbg("server_rsa_pub_key.size:%d\n", tls->hsd->server_rsa_pub_key.size);
+ }
+ /* else: ECDSA key. It is not used for generating encryption keys,
+ * it is used only to sign the EC public key (which comes in ServerKey message).
+ * Since we do not verify cert validity, verifying signature on EC public key
+ * wouldn't add any security. Thus, we do nothing here.
*/
- if (*der != 0) /* "ignore bits", should be 0 */
- xfunc_die();
- der++;
- der = enter_der_item(der, &end); /* enter SEQ */
- //memset(tls->server_rsa_pub_key, 0, sizeof(tls->server_rsa_pub_key));
- der_binary_to_pstm(&tls->server_rsa_pub_key.N, der, end); /* modulus */
- der = skip_der_item(der, end);
- der_binary_to_pstm(&tls->server_rsa_pub_key.e, der, end); /* exponent */
- tls->server_rsa_pub_key.size = pstm_unsigned_bin_size(&tls->server_rsa_pub_key.N);
- 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 int tls_xread_handshake_block(tls_state_t *tls, int min_len)
{
struct record_hdr *xhdr;
- uint8_t *certbuf;
- int len, len1;
+ int len = tls_xread_record(tls, "handshake record");
- len = xread_tls_block(tls);
xhdr = (void*)tls->inbuf;
- if (len < sizeof(*xhdr) + 10
+ if (len < min_len
|| xhdr->type != RECORD_TYPE_HANDSHAKE
- || xhdr->proto_maj != TLS_MAJ
- || xhdr->proto_min != TLS_MIN
) {
- tls_error_die(tls);
+ bad_record_die(tls, "handshake record", len);
}
dbg("got HANDSHAKE\n");
+ return len;
+}
+
+static ALWAYS_INLINE void fill_handshake_record_hdr(void *buf, unsigned type, unsigned len)
+{
+ struct handshake_hdr {
+ uint8_t type;
+ uint8_t len24_hi, len24_mid, len24_lo;
+ } *h = buf;
+
+ len -= 4;
+ h->type = type;
+ h->len24_hi = len >> 16;
+ h->len24_mid = len >> 8;
+ h->len24_lo = len & 0xff;
+}
+
+static void send_client_hello_and_alloc_hsd(tls_state_t *tls, const char *sni)
+{
+#define NUM_CIPHERS (7 + 6 * ENABLE_FEATURE_TLS_SHA1 + ALLOW_RSA_NULL_SHA256)
+ static const uint8_t ciphers[] = {
+ 0x00,2 + 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 */
+#if ENABLE_FEATURE_TLS_SHA1
+ 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, // 4 TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA - ok: openssl s_server ... -cipher ECDHE-RSA-AES256-SHA (might fail with older openssl)
+ // 0xC0,0x18, // TLS_ECDH_anon_WITH_AES_128_CBC_SHA
+ // 0xC0,0x19, // TLS_ECDH_anon_WITH_AES_256_CBC_SHA
+#endif
+ 0xC0,0x23, // 5 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, // 6 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, // 7 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"
+//TODO: GCM_SHA384 ciphers can be supported, only need sha384-based PRF?
+ 0xC0,0x2F, // 8 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:
+#if ENABLE_FEATURE_TLS_SHA1
+ // 0xC0,0x35, // TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA
+ // 0xC0,0x36, // TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA
+#endif
+ // 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
+#if ENABLE_FEATURE_TLS_SHA1
+ 0x00,0x2F, // 9 TLS_RSA_WITH_AES_128_CBC_SHA - ok: openssl s_server ... -cipher AES128-SHA
+ 0x00,0x35, //10 TLS_RSA_WITH_AES_256_CBC_SHA - ok: openssl s_server ... -cipher AES256-SHA
+#endif
+ 0x00,0x3C, //11 TLS_RSA_WITH_AES_128_CBC_SHA256 - ok: openssl s_server ... -cipher AES128-SHA256
+ 0x00,0x3D, //12 TLS_RSA_WITH_AES_256_CBC_SHA256 - ok: openssl s_server ... -cipher AES256-SHA256
+ 0x00,0x9C, //13 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
+ 0x00,0x02, //list len
+ 0x00,0x1d, //curve_x25519 (RFC 7748)
+ //0x00,0x1e, //curve_x448 (RFC 7748)
+ //0x00,0x17, //curve_secp256r1
+ //0x00,0x18, //curve_secp384r1
+ //0x00,0x19, //curve_secp521r1
+//TODO: implement secp256r1 (at least): dl.fedoraproject.org immediately aborts
+//if only x25519/x448 are advertised, seems to support only secpNNNr1 curves:
+// openssl s_client -connect dl.fedoraproject.org:443 -debug -tls1_2 -cipher ECDHE-RSA-AES128-GCM-SHA256
+//Peer signing digest: SHA512
+//Peer signature type: RSA
+//Server Temp Key: ECDH, P-256, 256 bits
+//TLSv1.2, Cipher is ECDHE-RSA-AES128-GCM-SHA256
+ };
+ //static const uint8_t signature_algorithms[] = {
+ // 000d
+ // 0020
+ // 001e
+ // 0601 0602 0603 0501 0502 0503 0401 0402 0403 0301 0302 0303 0201 0202 0203
+ //};
+
+ struct client_hello {
+ 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 + NUM_CIPHERS*2]; /* actually variable */
+ uint8_t comprtypes_len;
+ uint8_t comprtypes[1]; /* actually variable */
+ /* Extensions (SNI shown):
+ * hi,lo // len of all extensions
+ * 00,00 // extension_type: "Server Name"
+ * 00,0e // list len (there can be more than one SNI)
+ * 00,0c // len of 1st Server Name Indication
+ * 00 // name type: host_name
+ * 00,09 // name len
+ * "localhost" // name
+ */
+// GNU Wget 1.18 to cdn.kernel.org sends these extensions:
+// 0055
+// 0005 0005 0100000000 - status_request
+// 0000 0013 0011 00 000e 63646e 2e 6b65726e656c 2e 6f7267 - server_name
+// ff01 0001 00 - renegotiation_info
+// 0023 0000 - session_ticket
+// 000a 0008 0006001700180019 - supported_groups
+// 000b 0002 0100 - ec_point_formats
+// 000d 0016 0014 0401 0403 0501 0503 0601 0603 0301 0303 0201 0203 - signature_algorithms
+// wolfssl library sends this option, RFC 7627 (closes a security weakness, some servers may require it. TODO?):
+// 0017 0000 - extended master secret
+ };
+ struct client_hello *record;
+ uint8_t *ptr;
+ int len;
+ int ext_len;
+ int sni_len = sni ? strnlen(sni, 127 - 5) : 0;
+
+ ext_len = 0;
+ /* is.gd responds with "handshake failure" to our hello if there's no supported_groups element */
+ ext_len += sizeof(supported_groups);
+ if (sni_len)
+ ext_len += 9 + sni_len;
+
+ /* +2 is for "len of all extensions" 2-byte field */
+ len = sizeof(*record) + 2 + ext_len;
+ record = tls_get_zeroed_outbuf(tls, len);
+
+ fill_handshake_record_hdr(record, HANDSHAKE_CLIENT_HELLO, len);
+ record->proto_maj = TLS_MAJ; /* the "requested" version of the protocol, */
+ record->proto_min = TLS_MIN; /* can be higher than one in record headers */
+ tls_get_random(record->rand32, sizeof(record->rand32));
+ if (TLS_DEBUG_FIXED_SECRETS)
+ memset(record->rand32, 0x11, sizeof(record->rand32));
+ /* record->session_id_len = 0; - already is */
+
+ BUILD_BUG_ON(sizeof(ciphers) != 2 + 2 + NUM_CIPHERS*2 + 2);
+ memcpy(&record->cipherid_len16_hi, ciphers, sizeof(ciphers));
+
+ ptr = (void*)(record + 1);
+ *ptr++ = ext_len >> 8;
+ *ptr++ = ext_len;
+ if (sni_len) {
+ //ptr[0] = 0; //
+ //ptr[1] = 0; //extension_type
+ //ptr[2] = 0; //
+ ptr[3] = sni_len + 5; //list len
+ //ptr[4] = 0; //
+ ptr[5] = sni_len + 3; //len of 1st SNI
+ //ptr[6] = 0; //name type
+ //ptr[7] = 0; //
+ ptr[8] = sni_len; //name len
+ ptr = mempcpy(&ptr[9], sni, sni_len);
+ }
+ memcpy(ptr, supported_groups, sizeof(supported_groups));
+
+ tls->hsd = xzalloc(sizeof(*tls->hsd));
+ /* HANDSHAKE HASH: ^^^ + len if need to save saved_client_hello */
+ memcpy(tls->hsd->client_and_server_rand32, record->rand32, sizeof(record->rand32));
+/* HANDSHAKE HASH:
+ tls->hsd->saved_client_hello_size = len;
+ memcpy(tls->hsd->saved_client_hello, record, len);
+ */
+ dbg(">> CLIENT_HELLO\n");
+ /* Can hash immediately only if we know which MAC hash to use.
+ * So far we do know: it's sha256:
+ */
+ sha256_begin(&tls->hsd->handshake_hash_ctx);
+ xwrite_and_update_handshake_hash(tls, len);
+ /* if this would become infeasible: save tls->hsd->saved_client_hello,
+ * use "xwrite_handshake_record(tls, len)" here,
+ * and hash saved_client_hello later.
+ */
+}
+
+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;
+ uint8_t *cipherid;
+ uint8_t cipherid1;
+ int len, len24;
+
+ len = tls_xread_handshake_block(tls, 74 - 32);
+
+ 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 checked later */
+ || hp->proto_maj != TLS_MAJ
+ || hp->proto_min != TLS_MIN
+ ) {
+ bad_record_die(tls, "'server hello'", len);
+ }
+
+ cipherid = &hp->cipherid_hi;
+ len24 = hp->len24_lo;
+ if (hp->session_id_len != 32) {
+ if (hp->session_id_len != 0)
+ bad_record_die(tls, "'server hello'", len);
+
+ // session_id_len == 0: no session id
+ // "The server
+ // may return an empty session_id to indicate that the session will
+ // not be cached and therefore cannot be resumed."
+ cipherid -= 32;
+ len24 += 32; /* what len would be if session id would be present */
+ }
+
+ 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));
+
+ /* Set up encryption params based on selected cipher */
+#if 0
+#if ENABLE_FEATURE_TLS_SHA1
+ 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, // 4 TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA - ok: openssl s_server ... -cipher ECDHE-RSA-AES256-SHA (might fail with older openssl)
+ // 0xC0,0x18, // TLS_ECDH_anon_WITH_AES_128_CBC_SHA
+ // 0xC0,0x19, // TLS_ECDH_anon_WITH_AES_256_CBC_SHA
+#endif
+ 0xC0,0x23, // 5 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, // 6 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, // 7 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"
+//TODO: GCM_SHA384 ciphers can be supported, only need sha384-based PRF?
+ 0xC0,0x2F, // 8 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:
+#if ENABLE_FEATURE_TLS_SHA1
+ // 0xC0,0x35, // TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA
+ // 0xC0,0x36, // TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA
+#endif
+ // 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
+#if ENABLE_FEATURE_TLS_SHA1
+ 0x00,0x2F, // 9 TLS_RSA_WITH_AES_128_CBC_SHA - ok: openssl s_server ... -cipher AES128-SHA
+ 0x00,0x35, //10 TLS_RSA_WITH_AES_256_CBC_SHA - ok: openssl s_server ... -cipher AES256-SHA
+#endif
+ 0x00,0x3C, //11 TLS_RSA_WITH_AES_128_CBC_SHA256 - ok: openssl s_server ... -cipher AES128-SHA256
+ 0x00,0x3D, //12 TLS_RSA_WITH_AES_256_CBC_SHA256 - ok: openssl s_server ... -cipher AES256-SHA256
+ 0x00,0x9C, //13 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
+#endif
+ cipherid1 = cipherid[1];
+ tls->cipher_id = 0x100 * cipherid[0] + cipherid1;
+ 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 (ENABLE_FEATURE_TLS_SHA1 && cipherid1 <= 0x19) {
+ 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 ((ENABLE_FEATURE_TLS_SHA1 && cipherid1 == 0x2F)
+ || cipherid1 == 0x3C
+ || cipherid1 == 0x9C
+ ) {
+ tls->key_size = AES128_KEYSIZE;
+ }
+ if (ENABLE_FEATURE_TLS_SHA1 && 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("server chose cipher %04x\n", tls->cipher_id);
+ 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).
+ * It's not sha1 for AES_128_CBC_SHA - only MAC is sha1, not this hash.
+ */
+/* HANDSHAKE HASH:
+ sha256_begin(&tls->hsd->handshake_hash_ctx);
+ hash_handshake(tls, ">> client hello hash:%s",
+ tls->hsd->saved_client_hello, tls->hsd->saved_client_hello_size
+ );
+ hash_handshake(tls, "<< server hello hash:%s",
+ tls->inbuf + RECHDR_LEN, len
+ );
+ */
+}
+
+static void get_server_cert(tls_state_t *tls)
+{
+ struct record_hdr *xhdr;
+ uint8_t *certbuf;
+ int len, len1;
+
+ len = tls_xread_handshake_block(tls, 10);
+
+ xhdr = (void*)tls->inbuf;
certbuf = (void*)(xhdr + 1);
if (certbuf[0] != HANDSHAKE_CERTIFICATE)
- tls_error_die(tls);
- dbg("got CERTIFICATE\n");
+ bad_record_die(tls, "certificate", len);
+ dbg("<< CERTIFICATE\n");
// 4392 bytes:
// 0b 00|11|24 00|11|21 00|05|b0 30|82|05|ac|30|82|04|94|a0|03|02|01|02|02|11|00|9f|85|bf|66|4b|0c|dd|af|ca|50|86|79|50|1b|2b|e4|30|0d...
//Cert len=4388 ChainLen CertLen^ DER encoded X509 starts here. openssl x509 -in FILE -inform DER -noout -text
find_key_in_der_cert(tls, certbuf + 10, len);
}
+/* On input, len is known to be >= 4.
+ * The record is known to be SERVER_KEY_EXCHANGE.
+ */
+static void process_server_key(tls_state_t *tls, int len)
+{
+ struct record_hdr *xhdr;
+ uint8_t *keybuf;
+ int len1;
+ uint32_t t32;
+
+ xhdr = (void*)tls->inbuf;
+ keybuf = (void*)(xhdr + 1);
+//seen from is.gd: it selects curve_x25519:
+// 0c 00006e //SERVER_KEY_EXCHANGE, len
+// 03 //curve_type: named curve
+// 001d //curve_x25519
+//server-chosen EC point, and then signed_params
+// (RFC 8422: "A hash of the params, with the signature
+// appropriate to that hash applied. The private key corresponding
+// to the certified public key in the server's Certificate message is
+// used for signing.")
+//follow. Format unclear/guessed:
+// 20 //eccPubKeyLen
+// 25511923d73b70dd2f60e66ba2f3fda31a9c25170963c7a3a972e481dbb2835d //eccPubKey (32bytes)
+// 0203 //hashSigAlg: 2:SHA1 (4:SHA256 5:SHA384 6:SHA512), 3:ECDSA (1:RSA)
+// 0046 //len (16bit)
+// 30 44 //SEQ, len
+// 02 20 //INTEGER, len
+// 2e18e7c2a9badd0a70cd3059a6ab114539b9f5163568911147386cd77ed7c412 //32bytes
+//this item ^^^^^ is sometimes 33 bytes (with all container sizes also +1)
+// 02 20 //INTEGER, len
+// 64523d6216cb94c43c9b20e377d8c52c55be6703fd6730a155930c705eaf3af6 //32bytes
+//same about this item ^^^^^
+
+//seen from ftp.openbsd.org
+//(which only accepts ECDHE-RSA-AESnnn-GCM-SHAnnn and ECDHE-RSA-CHACHA20-POLY1305 ciphers):
+// 0c 000228 //SERVER_KEY_EXCHANGE, len
+// 03 //curve_type: named curve
+// 001d //curve_x25519
+// 20 //eccPubKeyLen
+// eef7a15c43b71a4c7eaa48a39369399cc4332e569ec90a83274cc92596705c1a //eccPubKey
+// 0401 //hashSigAlg: 4:SHA256, 1:RSA
+// 0200 //len
+// //0x200 bytes follow
+
+ /* Get and verify length */
+ len1 = get24be(keybuf + 1);
+ if (len1 > len - 4) tls_error_die(tls);
+ len = len1;
+ if (len < (1+2+1+32)) tls_error_die(tls);
+ keybuf += 4;
+
+ /* So far we only support curve_x25519 */
+ move_from_unaligned32(t32, keybuf);
+ if (t32 != htonl(0x03001d20))
+ bb_simple_error_msg_and_die("elliptic curve is not x25519");
+
+ memcpy(tls->hsd->ecc_pub_key32, keybuf + 4, 32);
+ tls->flags |= GOT_EC_KEY;
+ dbg("got eccPubKey\n");
+}
+
+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_zeroed_outbuf(tls, sizeof(*record));
+ //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;
+ // same as above:
+ record->type = HANDSHAKE_CERTIFICATE;
+ record->len24_lo = 3;
+
+ dbg(">> CERTIFICATE\n");
+ xwrite_and_update_handshake_hash(tls, sizeof(*record));
+}
+
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)
+ struct client_key_exchange {
+ uint8_t type;
+ uint8_t len24_hi, len24_mid, len24_lo;
+ uint8_t key[2 + 4 * 1024]; // size??
+ };
+//FIXME: better size estimate
+ struct client_key_exchange *record = tls_get_zeroed_outbuf(tls, sizeof(*record));
+ uint8_t rsa_premaster[RSA_PREMASTER_SIZE];
+ uint8_t x25519_premaster[CURVE25519_KEYSIZE];
+ uint8_t *premaster;
+ int premaster_size;
+ int len;
+
+ if (!(tls->flags & NEED_EC_KEY)) {
+ /* RSA */
+ if (!(tls->flags & GOT_CERT_RSA_KEY_ALG))
+ bb_simple_error_msg("server cert is not RSA");
+
+ tls_get_random(rsa_premaster, sizeof(rsa_premaster));
+ if (TLS_DEBUG_FIXED_SECRETS)
+ memset(rsa_premaster, 0x44, 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;
+ dump_hex("premaster:%s\n", rsa_premaster, sizeof(rsa_premaster));
+ len = psRsaEncryptPub(/*pool:*/ NULL,
+ /* psRsaKey_t* */ &tls->hsd->server_rsa_pub_key,
+ rsa_premaster, /*inlen:*/ sizeof(rsa_premaster),
+ record->key + 2, sizeof(record->key) - 2,
+ data_param_ignored
+ );
+ /* keylen16 exists for RSA (in TLS, not in SSL), but not for some other key types */
+ record->key[0] = len >> 8;
+ record->key[1] = len & 0xff;
+ len += 2;
+ premaster = rsa_premaster;
+ premaster_size = sizeof(rsa_premaster);
+ } else {
+ /* ECDHE */
+ static const uint8_t basepoint9[CURVE25519_KEYSIZE] = {9};
+ uint8_t privkey[CURVE25519_KEYSIZE]; //[32]
+
+ if (!(tls->flags & GOT_EC_KEY))
+ bb_simple_error_msg("server did not provide EC key");
+
+ /* Generate random private key, see RFC 7748 */
+ tls_get_random(privkey, sizeof(privkey));
+ privkey[0] &= 0xf8;
+ privkey[CURVE25519_KEYSIZE-1] = ((privkey[CURVE25519_KEYSIZE-1] & 0x7f) | 0x40);
+
+ /* Compute public key */
+ curve25519(record->key + 1, privkey, basepoint9);
+
+ /* Compute premaster using peer's public key */
+ dbg("computing x25519_premaster\n");
+ curve25519(x25519_premaster, privkey, tls->hsd->ecc_pub_key32);
+
+ len = CURVE25519_KEYSIZE;
+ record->key[0] = len;
+ len++;
+ premaster = x25519_premaster;
+ premaster_size = sizeof(x25519_premaster);
+ }
+
+ record->type = HANDSHAKE_CLIENT_KEY_EXCHANGE;
+ /* record->len24_hi = 0; - already is */
+ record->len24_mid = len >> 8;
+ record->len24_lo = len & 0xff;
+ len += 4;
+
+ dbg(">> CLIENT_KEY_EXCHANGE\n");
+ xwrite_and_update_handshake_hash(tls, len);
+
+ // RFC 5246
+ // For all key exchange methods, the same algorithm is used to convert
+ // the pre_master_secret into the master_secret. The pre_master_secret
+ // should be deleted from memory once the master_secret has been
+ // computed.
+ // master_secret = PRF(pre_master_secret, "master secret",
+ // ClientHello.random + ServerHello.random)
+ // [0..47];
+ // The master secret is always exactly 48 bytes in length. The length
+ // of the premaster secret will vary depending on key exchange method.
+ prf_hmac_sha256(/*tls,*/
+ tls->hsd->master_secret, sizeof(tls->hsd->master_secret),
+ premaster, premaster_size,
+ "master secret",
+ tls->hsd->client_and_server_rand32, sizeof(tls->hsd->client_and_server_rand32)
+ );
+ dump_hex("master secret:%s\n", tls->hsd->master_secret, sizeof(tls->hsd->master_secret));
+
+ // RFC 5246
+ // 6.3. Key Calculation
+ //
+ // The Record Protocol requires an algorithm to generate keys required
+ // by the current connection state (see Appendix A.6) from the security
+ // parameters provided by the handshake protocol.
+ //
+ // The master secret is expanded into a sequence of secure bytes, which
+ // is then split to a client write MAC key, a server write MAC key, a
+ // client write encryption key, and a server write encryption key. Each
+ // of these is generated from the byte sequence in that order. Unused
+ // values are empty. Some AEAD ciphers may additionally require a
+ // client write IV and a server write IV (see Section 6.2.3.3).
+ //
+ // When keys and MAC keys are generated, the master secret is used as an
+ // entropy source.
+ //
+ // To generate the key material, compute
+ //
+ // key_block = PRF(SecurityParameters.master_secret,
+ // "key expansion",
+ // SecurityParameters.server_random +
+ // SecurityParameters.client_random);
+ //
+ // until enough output has been generated. Then, the key_block is
+ // partitioned as follows:
+ //
+ // client_write_MAC_key[SecurityParameters.mac_key_length]
+ // server_write_MAC_key[SecurityParameters.mac_key_length]
+ // client_write_key[SecurityParameters.enc_key_length]
+ // server_write_key[SecurityParameters.enc_key_length]
+ // client_write_IV[SecurityParameters.fixed_iv_length]
+ // server_write_IV[SecurityParameters.fixed_iv_length]
{
- 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;
+ uint8_t tmp64[64];
+
+ /* make "server_rand32 + client_rand32" */
+ memcpy(&tmp64[0] , &tls->hsd->client_and_server_rand32[32], 32);
+ memcpy(&tmp64[32], &tls->hsd->client_and_server_rand32[0] , 32);
+
+ prf_hmac_sha256(/*tls,*/
+ tls->client_write_MAC_key, 2 * (tls->MAC_size + tls->key_size + tls->IV_size),
+ // also fills:
+ // server_write_MAC_key[]
+ // client_write_key[]
+ // server_write_key[]
+ // client_write_IV[]
+ // server_write_IV[]
+ tls->hsd->master_secret, sizeof(tls->hsd->master_secret),
+ "key expansion",
+ tmp64, 64
+ );
+ tls->client_write_key = tls->client_write_MAC_key + (2 * tls->MAC_size);
+ tls->server_write_key = tls->client_write_key + tls->key_size;
+ tls->client_write_IV = tls->server_write_key + tls->key_size;
+ tls->server_write_IV = tls->client_write_IV + tls->IV_size;
+ dump_hex("client_write_MAC_key:%s\n",
+ tls->client_write_MAC_key, tls->MAC_size
+ );
+ dump_hex("client_write_key:%s\n",
+ tls->client_write_key, tls->key_size
+ );
+ dump_hex("client_write_IV:%s\n",
+ tls->client_write_IV, tls->IV_size
+ );
+
+ aes_setkey(&tls->aes_decrypt, tls->server_write_key, tls->key_size);
+ aes_setkey(&tls->aes_encrypt, tls->client_write_key, tls->key_size);
+ {
+ uint8_t iv[AES_BLOCK_SIZE];
+ memset(iv, 0, AES_BLOCK_SIZE);
+ aes_encrypt_one_block(&tls->aes_encrypt, iv, tls->H);
}
- 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 */
+static const uint8_t rec_CHANGE_CIPHER_SPEC[] ALIGN1 = {
+ RECORD_TYPE_CHANGE_CIPHER_SPEC, TLS_MAJ, TLS_MIN, 00, 01,
+ 01
+};
- c += keyLen;
-#endif
-#endif // 0
+static void send_change_cipher_spec(tls_state_t *tls)
+{
+ dbg(">> CHANGE_CIPHER_SPEC\n");
+ xwrite(tls->ofd, rec_CHANGE_CIPHER_SPEC, sizeof(rec_CHANGE_CIPHER_SPEC));
+}
- struct client_key_exchange {
- struct record_hdr xhdr;
+// 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 send_client_finished(tls_state_t *tls)
+{
+ struct finished {
uint8_t type;
uint8_t len24_hi, len24_mid, len24_lo;
- uint8_t keylen16_hi, keylen16_lo; /* exist for RSA, but not for some other key types */
-//had a bug when had no keylen: we:
-//write(3, "\x16\x03\x03\x01\x84\x10\x00\x01\x80\xXX\xXX\xXX\xXX\xXX\xXX...", 393) = 393
-//openssl:
-//write to 0xe9a090 [0xf9ac20] (395 bytes => 395 (0x18B))
-//0000 - 16 03 03 01 86 10 00 01 -82 01 80 xx xx xx xx xx
- uint8_t key[384]; // size??
+ uint8_t prf_result[12];
};
- struct client_key_exchange record;
- uint8_t premaster[SSL_HS_RSA_PREMASTER_SIZE];
-
- memset(&record, 0, sizeof(record));
- record.xhdr.type = RECORD_TYPE_HANDSHAKE;
- record.xhdr.proto_maj = TLS_MAJ;
- record.xhdr.proto_min = TLS_MIN;
- record.xhdr.len16_hi = (sizeof(record) - sizeof(record.xhdr)) >> 8;
- record.xhdr.len16_lo = (sizeof(record) - sizeof(record.xhdr)) & 0xff;
- record.type = HANDSHAKE_CLIENT_KEY_EXCHANGE;
- //record.len24_hi = 0;
- record.len24_mid = (sizeof(record) - sizeof(record.xhdr) - 4) >> 8;
- record.len24_lo = (sizeof(record) - sizeof(record.xhdr) - 4) & 0xff;
- 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;
- psRsaEncryptPub(/*pool:*/ NULL,
- /* psRsaKey_t* */ &tls->server_rsa_pub_key,
- premaster, /*inlen:*/ sizeof(premaster),
- record.key, sizeof(record.key),
- data_param_ignored
+ struct finished *record = tls_get_outbuf(tls, sizeof(*record));
+ uint8_t handshake_hash[TLS_MAX_MAC_SIZE];
+ unsigned len;
+
+ fill_handshake_record_hdr(record, HANDSHAKE_FINISHED, sizeof(*record));
+
+ len = sha_end(&tls->hsd->handshake_hash_ctx, handshake_hash);
+
+ prf_hmac_sha256(/*tls,*/
+ record->prf_result, sizeof(record->prf_result),
+ tls->hsd->master_secret, sizeof(tls->hsd->master_secret),
+ "client finished",
+ handshake_hash, len
);
+ dump_hex("from secret: %s\n", tls->hsd->master_secret, sizeof(tls->hsd->master_secret));
+ dump_hex("from labelSeed: %s", "client finished", sizeof("client finished")-1);
+ dump_hex("%s\n", handshake_hash, sizeof(handshake_hash));
+ dump_hex("=> digest: %s\n", record->prf_result, sizeof(record->prf_result));
- xwrite(tls->fd, &record, sizeof(record));
+ dbg(">> FINISHED\n");
+ xwrite_encrypted(tls, sizeof(*record), RECORD_TYPE_HANDSHAKE);
}
-static void tls_handshake(tls_state_t *tls)
+void FAST_FUNC tls_handshake(tls_state_t *tls, const char *sni)
{
// Client RFC 5246 Server
// (*) - optional messages, not always sent
// <------- Finished
// Application Data <------> Application Data
int len;
+ int got_cert_req;
- 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);
+ send_client_hello_and_alloc_hsd(tls, sni);
+ get_server_hello(tls);
- //RFC 5246
+ // RFC 5246
// The server MUST send a Certificate message whenever the agreed-
// upon key exchange method uses certificates for authentication
// (this includes all key exchange methods defined in this document
//
// 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_block(tls);
- /* Next handshake type is not predetermined */
- switch (tls->inbuf[5]) {
- case HANDSHAKE_SERVER_KEY_EXCHANGE:
+ len = tls_xread_handshake_block(tls, 4);
+ if (tls->inbuf[RECHDR_LEN] == 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:
- // 0e 000000 (len:0)
- dbg("got SERVER_HELLO_DONE\n");
- send_client_key_exchange(tls);
- len = xread_tls_block(tls);
- break;
- default:
- tls_error_die(tls);
+ //
+ // RFC 8422 5.4. Server Key Exchange
+ // This message is sent when using the ECDHE_ECDSA, ECDHE_RSA, and
+ // ECDH_anon key exchange algorithms.
+ // This message is used to convey the server's ephemeral ECDH public key
+ // (and the corresponding elliptic curve domain parameters) to the
+ // client.
+ dbg("<< SERVER_KEY_EXCHANGE len:%u\n", len);
+ dump_raw_in("<< %s\n", tls->inbuf, RECHDR_LEN + len);
+ if (tls->flags & NEED_EC_KEY)
+ process_server_key(tls, len);
+
+ // read next handshake block
+ len = tls_xread_handshake_block(tls, 4);
+ }
+
+ got_cert_req = (tls->inbuf[RECHDR_LEN] == HANDSHAKE_CERTIFICATE_REQUEST);
+ if (got_cert_req) {
+ 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); - WRONG (breaks handshake hash calc) */
+ /* need to hash _all_ server replies first, up to ServerHelloDone */
+ len = tls_xread_handshake_block(tls, 4);
}
+
+ 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");
+
+ if (got_cert_req)
+ send_empty_client_cert(tls);
+
+ send_client_key_exchange(tls);
+
+ send_change_cipher_spec(tls);
+ /* from now on we should send encrypted */
+ /* tls->write_seq64_be = 0; - already is */
+ tls->flags |= ENCRYPT_ON_WRITE;
+
+ send_client_finished(tls);
+
+ /* Get CHANGE_CIPHER_SPEC */
+ len = tls_xread_record(tls, "switch to encrypted traffic");
+ if (len != 1 || memcmp(tls->inbuf, rec_CHANGE_CIPHER_SPEC, 6) != 0)
+ bad_record_die(tls, "switch to encrypted traffic", len);
+ dbg("<< CHANGE_CIPHER_SPEC\n");
+
+ if (ALLOW_RSA_NULL_SHA256
+ && tls->cipher_id == TLS_RSA_WITH_NULL_SHA256
+ ) {
+ tls->min_encrypted_len_on_read = tls->MAC_size;
+ } else
+ if (!(tls->flags & ENCRYPTION_AESGCM)) {
+ unsigned mac_blocks = (unsigned)(TLS_MAC_SIZE(tls) + AES_BLOCK_SIZE-1) / AES_BLOCK_SIZE;
+ /* all incoming packets now should be encrypted and have
+ * at least IV + (MAC padded to blocksize):
+ */
+ tls->min_encrypted_len_on_read = AES_BLOCK_SIZE + (mac_blocks * AES_BLOCK_SIZE);
+ } else {
+ tls->min_encrypted_len_on_read = 8 + AES_BLOCK_SIZE;
+ }
+ dbg("min_encrypted_len_on_read: %u\n", tls->min_encrypted_len_on_read);
+
+ /* Get (encrypted) FINISHED from the server */
+ len = tls_xread_record(tls, "'server finished'");
+ if (len < 4 || tls->inbuf[RECHDR_LEN] != HANDSHAKE_FINISHED)
+ bad_record_die(tls, "'server finished'", len);
+ dbg("<< FINISHED\n");
+ /* application data can be sent/received */
+
+ /* free handshake data */
+ psRsaKey_clear(&tls->hsd->server_rsa_pub_key);
+// if (PARANOIA)
+// memset(tls->hsd, 0, tls->hsd->hsd_size);
+ free(tls->hsd);
+ tls->hsd = NULL;
}
-int tls_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
-int tls_main(int argc UNUSED_PARAM, char **argv)
+static void tls_xwrite(tls_state_t *tls, int len)
{
- tls_state_t *tls;
- len_and_sockaddr *lsa;
- int fd;
-
- // INIT_G();
- // getopt32(argv, "myopts")
+ dbg(">> DATA\n");
+ xwrite_encrypted(tls, len, RECORD_TYPE_APPLICATION_DATA);
+}
- if (!argv[1])
- bb_show_usage();
+// To run a test server using openssl:
+// openssl req -x509 -newkey rsa:$((4096/4*3)) -keyout key.pem -out server.pem -nodes -days 99999 -subj '/CN=localhost'
+// openssl s_server -key key.pem -cert server.pem -debug -tls1_2
+//
+// Unencryped SHA256 example:
+// openssl req -x509 -newkey rsa:$((4096/4*3)) -keyout key.pem -out server.pem -nodes -days 99999 -subj '/CN=localhost'
+// openssl s_server -key key.pem -cert server.pem -debug -tls1_2 -cipher NULL
+// openssl s_client -connect 127.0.0.1:4433 -debug -tls1_2 -cipher NULL-SHA256
- lsa = xhost2sockaddr(argv[1], 443);
- fd = xconnect_stream(lsa);
+void FAST_FUNC tls_run_copy_loop(tls_state_t *tls, unsigned flags)
+{
+ int inbuf_size;
+ const int INBUF_STEP = 4 * 1024;
+ struct pollfd pfds[2];
- tls = new_tls_state();
- tls->fd = fd;
- tls_handshake(tls);
+ pfds[0].fd = STDIN_FILENO;
+ pfds[0].events = POLLIN;
+ pfds[1].fd = tls->ifd;
+ pfds[1].events = POLLIN;
- return EXIT_SUCCESS;
+ inbuf_size = INBUF_STEP;
+ for (;;) {
+ int nread;
+
+ if (safe_poll(pfds, 2, -1) < 0)
+ bb_simple_perror_msg_and_die("poll");
+
+ if (pfds[0].revents) {
+ void *buf;
+
+ dbg("STDIN HAS DATA\n");
+ buf = tls_get_outbuf(tls, inbuf_size);
+ nread = safe_read(STDIN_FILENO, buf, inbuf_size);
+ if (nread < 1) {
+ /* We'd want to do this: */
+ /* Close outgoing half-connection so they get EOF,
+ * but leave incoming alone so we can see response
+ */
+ //shutdown(tls->ofd, SHUT_WR);
+ /* But TLS has no way to encode this,
+ * doubt it's ok to do it "raw"
+ */
+ pfds[0].fd = -1;
+ tls_free_outbuf(tls); /* mem usage optimization */
+ if (flags & TLSLOOP_EXIT_ON_LOCAL_EOF)
+ break;
+ } else {
+ if (nread == inbuf_size) {
+ /* TLS has per record overhead, if input comes fast,
+ * read, encrypt and send bigger chunks
+ */
+ inbuf_size += INBUF_STEP;
+ if (inbuf_size > TLS_MAX_OUTBUF)
+ inbuf_size = TLS_MAX_OUTBUF;
+ }
+ tls_xwrite(tls, nread);
+ }
+ }
+ if (pfds[1].revents) {
+ dbg("NETWORK HAS DATA\n");
+ read_record:
+ nread = tls_xread_record(tls, "encrypted data");
+ if (nread < 1) {
+ /* TLS protocol has no real concept of one-sided shutdowns:
+ * if we get "TLS EOF" from the peer, writes will fail too
+ */
+ //pfds[1].fd = -1;
+ //close(STDOUT_FILENO);
+ //tls_free_inbuf(tls); /* mem usage optimization */
+ //continue;
+ break;
+ }
+ if (tls->inbuf[0] != RECORD_TYPE_APPLICATION_DATA)
+ bad_record_die(tls, "encrypted data", nread);
+ xwrite(STDOUT_FILENO, tls->inbuf + RECHDR_LEN, nread);
+ /* We may already have a complete next record buffered,
+ * can process it without network reads (and possible blocking)
+ */
+ if (tls_has_buffered_record(tls))
+ goto read_record;
+ }
+ }
}