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tls: add support for TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 cipher

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function                                             old     new   delta
xwrite_encrypted                                     209     605    +396
GHASH                                                  -     395    +395
aes_encrypt_1                                          -     382    +382
GMULT                                                  -     192    +192
tls_xread_record                                     489     659    +170
aes_encrypt_one_block                                  -      65     +65
aesgcm_setkey                                          -      58     +58
FlattenSzInBits                                        -      52     +52
tls_handshake                                       1890    1941     +51
xwrite_and_update_handshake_hash                      46      81     +35
xorbuf                                                 -      24     +24
aes_setkey                                             -      16     +16
psRsaEncryptPub                                      413     421      +8
stty_main                                           1221    1227      +6
ssl_client_main                                      138     143      +5
next_token                                           841     845      +4
spawn_ssl_client                                     218     219      +1
volume_id_probe_hfs_hfsplus                          564     563      -1
read_package_field                                   232     230      -2
i2cdetect_main                                       674     672      -2
fail_hunk                                            139     136      -3
parse_expr                                           891     883      -8
curve25519                                           802     793      -9
aes_cbc_decrypt                                      971     958     -13
xwrite_handshake_record                               43       -     -43
aes_cbc_encrypt                                      644     172    -472
------------------------------------------------------------------------------
(add/remove: 9/1 grow/shrink: 9/8 up/down: 1860/-553)        Total: 1307 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2018-11-23 17:21:38 +01:00
parent 03ad7ae081
commit 83e5c627e1
11 changed files with 479 additions and 93 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

17
include/libbb.h
View File

@ -736,10 +736,17 @@ struct hostent *xgethostbyname(const char *name) FAST_FUNC;
// + inet_common.c has additional IPv4-only stuff
struct tls_aes {
uint32_t key[60];
unsigned rounds;
};
#define TLS_MAX_MAC_SIZE 32
#define TLS_MAX_KEY_SIZE 32
#define TLS_MAX_IV_SIZE 4
struct tls_handshake_data; /* opaque */
typedef struct tls_state {
unsigned flags;
int ofd;
int ifd;
@ -748,6 +755,7 @@ typedef struct tls_state {
uint8_t encrypt_on_write;
unsigned MAC_size;
unsigned key_size;
unsigned IV_size;
uint8_t *outbuf;
int outbuf_size;
@ -769,12 +777,21 @@ typedef struct tls_state {
/*uint64_t read_seq64_be;*/
uint64_t write_seq64_be;
/*uint8_t *server_write_MAC_key;*/
uint8_t *client_write_key;
uint8_t *server_write_key;
uint8_t *client_write_IV;
uint8_t *server_write_IV;
uint8_t client_write_MAC_key[TLS_MAX_MAC_SIZE];
uint8_t server_write_MAC_k__[TLS_MAX_MAC_SIZE];
uint8_t client_write_k__[TLS_MAX_KEY_SIZE];
uint8_t server_write_k__[TLS_MAX_KEY_SIZE];
uint8_t client_write_I_[TLS_MAX_IV_SIZE];
uint8_t server_write_I_[TLS_MAX_IV_SIZE];
struct tls_aes aes_encrypt;
struct tls_aes aes_decrypt;
uint8_t H[16]; //used by AES_GCM
} tls_state_t;
static inline tls_state_t *new_tls_state(void)

306
networking/tls.c
View File

@ -13,16 +13,17 @@
//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_fe.o
////kbuild:lib-$(CONFIG_TLS) += tls_aes_gcm.o
#include "tls.h"
//Tested against kernel.org:
//TLS 1.2
#define TLS_MAJ 3
#define TLS_MIN 3
//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
@ -36,7 +37,7 @@
//#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_RSA_WITH_AES_128_GCM_SHA256 // ok, no SERVER_KEY_EXCHANGE
// works against "openssl s_server -cipher NULL"
// and against wolfssl-3.9.10-stable/examples/server/server.c:
@ -60,6 +61,11 @@
// bug #11456: host is.gd accepts only ECDHE-ECDSA-foo (the simplest which works: ECDHE-ECDSA-AES128-SHA 0xC009)
#define CIPHER_ID3 TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA
// ftp.openbsd.org only supports ECDHE-RSA-AESnnn-GCM-SHAnnn or ECDHE-RSA-CHACHA20-POLY1305
#define CIPHER_ID4 TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256
#define NUM_CIPHERS 4
#define TLS_DEBUG 0
#define TLS_DEBUG_HASH 0
@ -207,7 +213,6 @@ enum {
SHA1_OUTSIZE = 20,
SHA256_OUTSIZE = 32,
AES_BLOCKSIZE = 16,
AES128_KEYSIZE = 16,
AES256_KEYSIZE = 32,
@ -216,7 +221,7 @@ enum {
RECHDR_LEN = 5,
/* 8 = 3+5. 3 extra bytes result in record data being 32-bit aligned */
OUTBUF_PFX = 8 + AES_BLOCKSIZE, /* header + IV */
OUTBUF_PFX = 8 + AES_BLOCK_SIZE, /* header + IV */
OUTBUF_SFX = TLS_MAX_MAC_SIZE + TLS_MAX_CRYPTBLOCK_SIZE, /* MAC + padding */
// RFC 5246
@ -263,8 +268,11 @@ struct record_hdr {
};
enum {
KEY_ALG_RSA,
KEY_ALG_ECDSA,
NEED_EC_KEY = 1 << 0,
GOT_CERT_RSA_KEY_ALG = 1 << 1,
GOT_CERT_ECDSA_KEY_ALG = 1 << 2,
GOT_EC_KEY = 1 << 3,
ENCRYPTION_AESGCM = 1 << 4,
};
struct tls_handshake_data {
/* In bbox, md5/sha1/sha256 ctx's are the same structure */
@ -273,14 +281,14 @@ struct tls_handshake_data {
uint8_t client_and_server_rand32[2 * 32];
uint8_t master_secret[48];
smallint key_alg;
//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];
unsigned saved_client_hello_size;
uint8_t saved_client_hello[1];
/* HANDSHAKE HASH: */
//unsigned saved_client_hello_size;
//uint8_t saved_client_hello[1];
};
@ -609,7 +617,7 @@ static void *tls_get_zeroed_outbuf(tls_state_t *tls, int len)
return record;
}
static void xwrite_encrypted(tls_state_t *tls, unsigned size, unsigned type)
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;
@ -619,7 +627,7 @@ static void xwrite_encrypted(tls_state_t *tls, unsigned size, unsigned type)
if (CIPHER_ID1 != TLS_RSA_WITH_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_BLOCKSIZE); /* place for IV */
xhdr = (void*)(buf - RECHDR_LEN - AES_BLOCK_SIZE); /* place for IV */
}
xhdr->type = type;
@ -722,7 +730,7 @@ static void xwrite_encrypted(tls_state_t *tls, unsigned size, unsigned type)
// AES_128_CBC Block 16 16 16
// AES_256_CBC Block 32 16 16
tls_get_random(buf - AES_BLOCKSIZE, AES_BLOCKSIZE); /* IV */
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->MAC_size);
@ -742,23 +750,24 @@ static void xwrite_encrypted(tls_state_t *tls, unsigned size, unsigned type)
// 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_BLOCKSIZE - 1);
padding_length = (~size) & (AES_BLOCK_SIZE - 1);
do {
buf[size++] = padding_length; /* padding */
} while ((size & (AES_BLOCKSIZE - 1)) != 0);
} while ((size & (AES_BLOCK_SIZE - 1)) != 0);
/* Encrypt content+MAC+padding in place */
//optimize key setup
aes_cbc_encrypt(
tls->client_write_key, tls->key_size, /* selects 128/256 */
buf - AES_BLOCKSIZE, /* IV */
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_BLOCKSIZE, size, padding_length);
size += AES_BLOCKSIZE; /* + IV */
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);
@ -766,9 +775,98 @@ static void xwrite_encrypted(tls_state_t *tls, unsigned size, unsigned type)
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)
{
//go for [16]
uint8_t aad[13];
uint8_t nonce[12 + 4]; /* +4 creates space for AES block counter */
uint8_t scratch[AES_BLOCK_SIZE]; //[16]
uint8_t authtag[AES_BLOCK_SIZE]; //[16]
uint8_t *buf;
struct record_hdr *xhdr;
unsigned remaining;
unsigned cnt;
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;
aad[12] = size & 0xff;
memcpy(nonce, tls->client_write_IV, 4);
memcpy(nonce + 4, &tls->write_seq64_be, 8);
memcpy(aad, &tls->write_seq64_be, 8);
memcpy(buf - 8, &tls->write_seq64_be, 8);
//optimize
/* seq64 is not used later in this func, can increment here */
tls->write_seq64_be = SWAP_BE64(1 + SWAP_BE64(tls->write_seq64_be));
#define COUNTER(v) (*(uint32_t*)(v + 12))
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;
}
//optimize fixed sizes
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(authtag, scratch, sizeof(authtag));
memcpy(buf, authtag, sizeof(authtag));
#undef COUNTER
/* 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);
}
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)
{
//if (!tls->encrypt_on_write) {
uint8_t *buf = tls->outbuf + OUTBUF_PFX;
struct record_hdr *xhdr = (void*)(buf - RECHDR_LEN);
@ -780,9 +878,6 @@ static void xwrite_handshake_record(tls_state_t *tls, unsigned size)
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);
// return;
//}
//xwrite_encrypted(tls, size, RECORD_TYPE_HANDSHAKE);
}
static void xwrite_and_update_handshake_hash(tls_state_t *tls, unsigned size)
@ -826,6 +921,52 @@ static const char *alert_text(int code)
return itoa(code);
}
static void tls_aesgcm_decrypt(tls_state_t *tls, uint8_t *buf, int size)
{
//go for [16]
//uint8_t aad[13];
uint8_t nonce[12 + 4]; /* +4 creates space for AES block counter */
uint8_t scratch[AES_BLOCK_SIZE]; //[16]
//uint8_t authtag[AES_BLOCK_SIZE]; //[16]
unsigned remaining;
unsigned cnt;
//aad[8] = type;
//aad[9] = TLS_MAJ;
//aad[10] = TLS_MIN;
//aad[11] = size >> 8;
//aad[12] = size & 0xff;
memcpy(nonce, tls->server_write_IV, 4);
memcpy(nonce + 4, buf, 8);
buf += 8;
#define COUNTER(v) (*(uint32_t*)(v + 12))
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;
xorbuf(buf, scratch, n);
buf += n;
remaining -= n;
}
////optimize fixed sizes
//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(authtag, scratch, sizeof(authtag));
//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;
@ -896,35 +1037,45 @@ static int tls_xread_record(tls_state_t *tls, const char *expected)
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);
memmove(p, p + 8, sz);
dbg("encrypted size:%u\n", sz);
} else
if (tls->min_encrypted_len_on_read > tls->MAC_size) {
/* AES+SHA */
uint8_t *p = tls->inbuf + RECHDR_LEN;
int padding_len;
if (sz & (AES_BLOCKSIZE-1)
|| sz < (int)tls->min_encrypted_len_on_read
) {
bb_error_msg_and_die("bad encrypted len:%u < %u",
sz, tls->min_encrypted_len_on_read);
}
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_BLOCKSIZE; /* we will overwrite IV now */
sz -= AES_BLOCK_SIZE; /* we will overwrite IV now */
aes_cbc_decrypt(
tls->server_write_key, tls->key_size, /* selects 128/256 */
p, /* IV */
p + AES_BLOCKSIZE, sz, /* ciphertext */
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 + padding_len; /* drop MAC and padding */
//if (sz < 0)
// bb_error_msg_and_die("bad padding size:%u", padding_len);
} 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_error_msg_and_die("encrypted data too short");
@ -964,7 +1115,8 @@ static int tls_xread_record(tls_state_t *tls, const char *expected)
* in our FINISHED record must include data of incoming packets too!
*/
if (tls->inbuf[0] == RECORD_TYPE_HANDSHAKE
&& tls->MAC_size != 0 /* do we know which hash to use? (server_hello() does not!) */
/* HANDSHAKE HASH: */
// && do_we_know_which_hash_to_use /* server_hello() might not know it in the future! */
) {
hash_handshake(tls, "<< hash:%s", tls->inbuf + RECHDR_LEN, sz);
}
@ -1198,16 +1350,16 @@ static void find_key_in_der_cert(tls_state_t *tls, uint8_t *der, int len)
};
if (memcmp(der, OID_RSA_KEY_ALG, sizeof(OID_RSA_KEY_ALG)) == 0) {
dbg("RSA key\n");
tls->hsd->key_alg = KEY_ALG_RSA;
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");
tls->hsd->key_alg = KEY_ALG_ECDSA;
tls->flags |= GOT_CERT_ECDSA_KEY_ALG;
} else
bb_error_msg_and_die("not RSA or ECDSA key");
bb_error_msg_and_die("not RSA or ECDSA cert");
}
if (tls->hsd->key_alg == KEY_ALG_RSA) {
if (tls->flags & GOT_CERT_RSA_KEY_ALG) {
/* parse RSA key: */
//based on getAsnRsaPubKey(), pkcs1ParsePrivBin() is also of note
/* skip subjectPublicKeyInfo.algorithm */
@ -1301,7 +1453,7 @@ static void send_client_hello_and_alloc_hsd(tls_state_t *tls, const char *sni)
uint8_t session_id_len;
/* uint8_t session_id[]; */
uint8_t cipherid_len16_hi, cipherid_len16_lo;
uint8_t cipherid[2 * (2 + !!CIPHER_ID2 + !!CIPHER_ID3)]; /* actually variable */
uint8_t cipherid[2 * (1 + NUM_CIPHERS)]; /* actually variable */
uint8_t comprtypes_len;
uint8_t comprtypes[1]; /* actually variable */
/* Extensions (SNI shown):
@ -1364,6 +1516,10 @@ static void send_client_hello_and_alloc_hsd(tls_state_t *tls, const char *sni)
if ((CIPHER_ID3 >> 8) != 0) record->cipherid[6] = CIPHER_ID3 >> 8;
/*************************/ record->cipherid[7] = CIPHER_ID3 & 0xff;
#endif
#if CIPHER_ID4
if ((CIPHER_ID4 >> 8) != 0) record->cipherid[6] = CIPHER_ID4 >> 8;
/*************************/ record->cipherid[7] = CIPHER_ID4 & 0xff;
#endif
record->comprtypes_len = 1;
/* record->comprtypes[0] = 0; */
@ -1385,15 +1541,23 @@ static void send_client_hello_and_alloc_hsd(tls_state_t *tls, const char *sni)
}
memcpy(ptr, supported_groups, sizeof(supported_groups));
dbg(">> CLIENT_HELLO\n");
/* Can hash it only when we know which MAC hash to use */
/*xwrite_and_update_handshake_hash(tls, len); - WRONG! */
xwrite_handshake_record(tls, len);
tls->hsd = xzalloc(sizeof(*tls->hsd) + len);
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);
memcpy(tls->hsd->client_and_server_rand32, record->rand32, sizeof(record->rand32));
*/
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)
@ -1463,18 +1627,28 @@ static void get_server_hello(tls_state_t *tls)
if (cipher == TLS_RSA_WITH_AES_128_CBC_SHA
|| cipher == TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA
) {
if (cipher == TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA)
tls->flags |= NEED_EC_KEY;
tls->key_size = AES128_KEYSIZE;
tls->MAC_size = SHA1_OUTSIZE;
}
else { /* TLS_RSA_WITH_AES_256_CBC_SHA256 */
else
if (cipher == TLS_RSA_WITH_AES_256_CBC_SHA256) {
tls->key_size = AES256_KEYSIZE;
tls->MAC_size = SHA256_OUTSIZE;
}
else { /* TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 */
tls->flags |= NEED_EC_KEY | ENCRYPTION_AESGCM;
tls->key_size = AES128_KEYSIZE;
/* tls->MAC_size = 0; */
tls->IV_size = 4;
}
/* 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
@ -1482,6 +1656,7 @@ static void get_server_hello(tls_state_t *tls)
hash_handshake(tls, "<< server hello hash:%s",
tls->inbuf + RECHDR_LEN, len
);
*/
}
static void get_server_cert(tls_state_t *tls)
@ -1548,7 +1723,7 @@ static void process_server_key(tls_state_t *tls, int len)
// 64523d6216cb94c43c9b20e377d8c52c55be6703fd6730a155930c705eaf3af6 //32bytes
//same about this item ^^^^^
//seen from www.openbsd.org
//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
@ -1572,6 +1747,7 @@ static void process_server_key(tls_state_t *tls, int len)
bb_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");
}
@ -1612,7 +1788,11 @@ static void send_client_key_exchange(tls_state_t *tls)
int premaster_size;
int len;
if (tls->hsd->key_alg == KEY_ALG_RSA) {
if (!(tls->flags & NEED_EC_KEY)) {
/* RSA */
if (!(tls->flags & GOT_CERT_RSA_KEY_ALG))
bb_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));
@ -1636,10 +1816,13 @@ static void send_client_key_exchange(tls_state_t *tls)
premaster = rsa_premaster;
premaster_size = sizeof(rsa_premaster);
} else {
/* KEY_ALG_ECDSA */
/* ECDHE */
static const uint8_t basepoint9[CURVE25519_KEYSIZE] = {9};
uint8_t privkey[CURVE25519_KEYSIZE]; //[32]
if (!(tls->flags & GOT_EC_KEY))
bb_error_msg("server did not provide EC key");
/* Generate random private key, see RFC 7748 */
tls_get_random(privkey, sizeof(privkey));
privkey[0] &= 0xf8;
@ -1727,23 +1910,32 @@ static void send_client_key_exchange(tls_state_t *tls)
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->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
);
aesgcm_setkey(tls->H, &tls->aes_encrypt, tls->client_write_key, tls->key_size);
aes_setkey(&tls->aes_decrypt, tls->server_write_key, tls->key_size);
}
}
@ -1876,7 +2068,7 @@ void FAST_FUNC tls_handshake(tls_state_t *tls, const char *sni)
// client.
dbg("<< SERVER_KEY_EXCHANGE len:%u\n", len);
dump_raw_in("<< %s\n", tls->inbuf, RECHDR_LEN + len);
if (tls->hsd->key_alg == KEY_ALG_ECDSA)
if (tls->flags & NEED_EC_KEY)
process_server_key(tls, len);
// read next handshake block
@ -1922,18 +2114,22 @@ void FAST_FUNC tls_handshake(tls_state_t *tls, const char *sni)
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 (CIPHER_ID1 == TLS_RSA_WITH_NULL_SHA256
&& tls->cipher_id == TLS_RSA_WITH_NULL_SHA256
) {
tls->min_encrypted_len_on_read = tls->MAC_size;
} else {
unsigned mac_blocks = (unsigned)(tls->MAC_size + AES_BLOCKSIZE-1) / AES_BLOCKSIZE;
} else
if (!(tls->flags & ENCRYPTION_AESGCM)) {
unsigned mac_blocks = (unsigned)(tls->MAC_size + 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_BLOCKSIZE + (mac_blocks * AES_BLOCKSIZE);
dbg("min_encrypted_len_on_read: %u", tls->min_encrypted_len_on_read);
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'");

3
networking/tls.h
View File

@ -78,6 +78,8 @@ typedef int16_t int16;
#define PUBKEY_TYPE 0x01
#define PRIVKEY_TYPE 0x02
#define AES_BLOCK_SIZE 16
void tls_get_random(void *buf, unsigned len);
#define matrixCryptoGetPrngData(buf, len, userPtr) (tls_get_random(buf, len), PS_SUCCESS)
@ -96,5 +98,6 @@ void tls_get_random(void *buf, unsigned len);
#include "tls_pstm.h"
#include "tls_symmetric.h"
#include "tls_aes.h"
#include "tls_aesgcm.h"
#include "tls_rsa.h"
#include "tls_fe.h"

15
networking/tls_aes.c
View File

@ -340,8 +340,12 @@ static void aes_encrypt_1(unsigned astate[16], unsigned rounds, const uint32_t *
AddRoundKey(astate, RoundKey);
}
#if 0 // UNUSED
static void aes_encrypt_one_block(unsigned rounds, const uint32_t *RoundKey, const void *data, void *dst)
void FAST_FUNC aes_setkey(struct tls_aes *aes, const void *key, unsigned key_len)
{
aes->rounds = KeyExpansion(aes->key, key, key_len);
}
void FAST_FUNC aes_encrypt_one_block(struct tls_aes *aes, const void *data, void *dst)
{
unsigned astate[16];
unsigned i;
@ -351,13 +355,12 @@ static void aes_encrypt_one_block(unsigned rounds, const uint32_t *RoundKey, con
for (i = 0; i < 16; i++)
astate[i] = pt[i];
aes_encrypt_1(astate, rounds, RoundKey);
aes_encrypt_1(astate, aes->rounds, aes->key);
for (i = 0; i < 16; i++)
ct[i] = astate[i];
}
#endif
void aes_cbc_encrypt(const void *key, int klen, void *iv, const void *data, size_t len, void *dst)
void FAST_FUNC aes_cbc_encrypt(const void *key, int klen, void *iv, const void *data, size_t len, void *dst)
{
uint32_t RoundKey[60];
uint8_t iv2[16];
@ -420,7 +423,7 @@ static void aes_decrypt_one_block(unsigned rounds, const uint32_t *RoundKey, con
}
#endif
void aes_cbc_decrypt(const void *key, int klen, void *iv, const void *data, size_t len, void *dst)
void FAST_FUNC aes_cbc_decrypt(const void *key, int klen, void *iv, const void *data, size_t len, void *dst)
{
uint32_t RoundKey[60];
uint8_t iv2[16];

8
networking/tls_aes.h
View File

@ -6,5 +6,9 @@
* Selected few declarations for AES.
*/
void aes_cbc_encrypt(const void *key, int klen, void *iv, const void *data, size_t len, void *dst);
void aes_cbc_decrypt(const void *key, int klen, void *iv, const void *data, size_t len, void *dst);
void aes_setkey(struct tls_aes *aes, const void *key, unsigned key_len) FAST_FUNC;
void aes_encrypt_one_block(struct tls_aes *aes, const void *data, void *dst) FAST_FUNC;
void aes_cbc_encrypt(const void *key, int klen, void *iv, const void *data, size_t len, void *dst) FAST_FUNC;
void aes_cbc_decrypt(const void *key, int klen, void *iv, const void *data, size_t len, void *dst) FAST_FUNC;

148
networking/tls_aesgcm.c Normal file
View File

@ -0,0 +1,148 @@
/*
* Copyright (C) 2018 Denys Vlasenko
*
* Licensed under GPLv2, see file LICENSE in this source tree.
*/
#include "tls.h"
typedef uint8_t byte;
typedef uint32_t word32;
#define XMEMSET memset
#define XMEMCPY memcpy
#define TLS_MAJ 3
#define TLS_MIN 3
#define RECHDR_LEN 5
#define OUTBUF_PFX (8 + AES_BLOCK_SIZE)
void FAST_FUNC xorbuf(void* buf, const void* mask, unsigned count)
{
word32 i;
byte* b = (byte*)buf;
const byte* m = (const byte*)mask;
for (i = 0; i < count; i++)
b[i] ^= m[i];
}
/* wolfssl-3.15.3/wolfcrypt/src/aes.c */
static void FlattenSzInBits(byte* buf, word32 sz)
{
/* Multiply the sz by 8 */
word32 szHi = (sz >> (8*sizeof(sz) - 3));
sz <<= 3;
/* copy over the words of the sz into the destination buffer */
buf[0] = (szHi >> 24) & 0xff;
buf[1] = (szHi >> 16) & 0xff;
buf[2] = (szHi >> 8) & 0xff;
buf[3] = szHi & 0xff;
buf[4] = (sz >> 24) & 0xff;
buf[5] = (sz >> 16) & 0xff;
buf[6] = (sz >> 8) & 0xff;
buf[7] = sz & 0xff;
}
static void RIGHTSHIFTX(byte* x)
{
int i;
int carryOut = 0;
int carryIn = 0;
int borrow = x[15] & 0x01;
for (i = 0; i < AES_BLOCK_SIZE; i++) {
carryOut = x[i] & 0x01;
x[i] = (x[i] >> 1) | (carryIn ? 0x80 : 0);
carryIn = carryOut;
}
if (borrow) x[0] ^= 0xE1;
}
static void GMULT(byte* X, byte* Y)
{
byte Z[AES_BLOCK_SIZE];
byte V[AES_BLOCK_SIZE];
int i, j;
XMEMSET(Z, 0, AES_BLOCK_SIZE);
XMEMCPY(V, X, AES_BLOCK_SIZE);
for (i = 0; i < AES_BLOCK_SIZE; i++)
{
byte y = Y[i];
for (j = 0; j < 8; j++)
{
if (y & 0x80) {
xorbuf(Z, V, AES_BLOCK_SIZE);
}
RIGHTSHIFTX(V);
y = y << 1;
}
}
XMEMCPY(X, Z, AES_BLOCK_SIZE);
}
void FAST_FUNC aesgcm_GHASH(byte* h, const byte* a, unsigned aSz, const byte* c,
unsigned cSz, byte* s, unsigned sSz)
{
byte x[AES_BLOCK_SIZE];
byte scratch[AES_BLOCK_SIZE];
word32 blocks, partial;
//was: byte* h = aes->H;
XMEMSET(x, 0, AES_BLOCK_SIZE);
/* Hash in A, the Additional Authentication Data */
if (aSz != 0 && a != NULL) {
blocks = aSz / AES_BLOCK_SIZE;
partial = aSz % AES_BLOCK_SIZE;
while (blocks--) {
xorbuf(x, a, AES_BLOCK_SIZE);
GMULT(x, h);
a += AES_BLOCK_SIZE;
}
if (partial != 0) {
XMEMSET(scratch, 0, AES_BLOCK_SIZE);
XMEMCPY(scratch, a, partial);
xorbuf(x, scratch, AES_BLOCK_SIZE);
GMULT(x, h);
}
}
/* Hash in C, the Ciphertext */
if (cSz != 0 && c != NULL) {
blocks = cSz / AES_BLOCK_SIZE;
partial = cSz % AES_BLOCK_SIZE;
while (blocks--) {
xorbuf(x, c, AES_BLOCK_SIZE);
GMULT(x, h);
c += AES_BLOCK_SIZE;
}
if (partial != 0) {
XMEMSET(scratch, 0, AES_BLOCK_SIZE);
XMEMCPY(scratch, c, partial);
xorbuf(x, scratch, AES_BLOCK_SIZE);
GMULT(x, h);
}
}
/* Hash in the lengths of A and C in bits */
FlattenSzInBits(&scratch[0], aSz);
FlattenSzInBits(&scratch[8], cSz);
xorbuf(x, scratch, AES_BLOCK_SIZE);
GMULT(x, h);
/* Copy the result into s. */
XMEMCPY(s, x, sSz);
}
void FAST_FUNC aesgcm_setkey(uint8_t H[16], struct tls_aes *aes, const byte* key, unsigned len)
{
byte iv[AES_BLOCK_SIZE];
aes_setkey(aes, key, len);
memset(iv, 0, AES_BLOCK_SIZE);
aes_encrypt_one_block(aes, iv, H);
}

15
networking/tls_aesgcm.h Normal file
View File

@ -0,0 +1,15 @@
/*
* Copyright (C) 2018 Denys Vlasenko
*
* Licensed under GPLv2, see file LICENSE in this source tree.
*/
void xorbuf(void* buf, const void* mask, unsigned count) FAST_FUNC;
void aesgcm_GHASH(uint8_t* h,
const uint8_t* a, unsigned aSz,
const uint8_t* c, unsigned cSz,
uint8_t* s, unsigned sSz
) FAST_FUNC;
void aesgcm_setkey(uint8_t H[16], struct tls_aes *aes, const uint8_t* key, unsigned len) FAST_FUNC;

2
networking/tls_fe.c
View File

@ -554,7 +554,7 @@ static void xc_double(byte *x3, byte *z3,
fe_mul_c(z3, x1sq, 4);
}
void curve25519(byte *result, const byte *e, const byte *q)
void FAST_FUNC curve25519(byte *result, const byte *e, const byte *q)
{
int i;

2
networking/tls_fe.h
View File

@ -4,4 +4,4 @@
* Licensed under GPLv2, see file LICENSE in this source tree.
*/
#define CURVE25519_KEYSIZE 32
void curve25519(uint8_t *result, const uint8_t *e, const uint8_t *q);
void curve25519(uint8_t *result, const uint8_t *e, const uint8_t *q) FAST_FUNC;

2
networking/tls_rsa.c
View File

@ -179,7 +179,7 @@ done:
return res;
}
int32 psRsaEncryptPub(psPool_t *pool, psRsaKey_t *key,
int32 FAST_FUNC psRsaEncryptPub(psPool_t *pool, psRsaKey_t *key,
unsigned char *in, uint32 inlen,
unsigned char *out, uint32 outlen, void *data)
{

2
networking/tls_rsa.h
View File

@ -17,4 +17,4 @@ typedef struct {
psRsaEncryptPub( key, in, inlen, out, outlen)
int32 psRsaEncryptPub(psPool_t *pool, psRsaKey_t *key,
unsigned char *in, uint32 inlen,
unsigned char *out, uint32 outlen, void *data);
unsigned char *out, uint32 outlen, void *data) FAST_FUNC;