tls: add 2nd cipher_id, TLS_RSA_WITH_AES_128_CBC_SHA, so far it doesn't work

Good news that TLS_RSA_WITH_AES_256_CBC_SHA256 still works with new code ;)

This change adds inevitable extension to have different sized hashes and AES key sizes.
In libbb, md5_end() and shaX_end() are extended to return result size instead of void -
this helps *a lot* in tls (the cost is ~5 bytes per _end() function).

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2017-01-24 16:00:54 +01:00
parent 9a64c3337c
commit 49ecee098d
6 changed files with 290 additions and 192 deletions

View File

@ -166,7 +166,7 @@ static uint8_t *hash_file(const char *filename, unsigned sha3_width)
} context;
uint8_t *hash_value;
void FAST_FUNC (*update)(void*, const void*, size_t);
void FAST_FUNC (*final)(void*, void*);
unsigned FAST_FUNC (*final)(void*, void*);
char hash_algo;
src_fd = open_or_warn_stdin(filename);

View File

@ -713,18 +713,19 @@ struct hostent *xgethostbyname(const char *name) FAST_FUNC;
// Also mount.c and inetd.c are using gethostbyname(),
// + inet_common.c has additional IPv4-only stuff
#define SHA256_INSIZE 64
#define SHA256_OUTSIZE 32
#define AES_BLOCKSIZE 16
#define AES128_KEYSIZE 16
#define AES256_KEYSIZE 32
#define TLS_MAX_MAC_SIZE 32
#define TLS_MAX_KEY_SIZE 32
struct tls_handshake_data; /* opaque */
typedef struct tls_state {
int ofd;
int ifd;
int min_encrypted_len_on_read;
uint16_t cipher_id;
uint8_t encrypt_on_write;
unsigned MAC_size;
unsigned key_size;
uint8_t *outbuf;
int outbuf_size;
@ -746,10 +747,12 @@ typedef struct tls_state {
/*uint64_t read_seq64_be;*/
uint64_t write_seq64_be;
uint8_t client_write_MAC_key[SHA256_OUTSIZE];
uint8_t server_write_MAC_key[SHA256_OUTSIZE];
uint8_t client_write_key[AES256_KEYSIZE];
uint8_t server_write_key[AES256_KEYSIZE];
uint8_t *client_write_key;
uint8_t *server_write_key;
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];
} tls_state_t;
static inline tls_state_t *new_tls_state(void)
@ -760,6 +763,7 @@ static inline tls_state_t *new_tls_state(void)
void tls_handshake(tls_state_t *tls, const char *sni) FAST_FUNC;
void tls_run_copy_loop(tls_state_t *tls) FAST_FUNC;
void socket_want_pktinfo(int fd) FAST_FUNC;
ssize_t send_to_from(int fd, void *buf, size_t len, int flags,
const struct sockaddr *to,
@ -1799,19 +1803,23 @@ typedef struct sha3_ctx_t {
} sha3_ctx_t;
void md5_begin(md5_ctx_t *ctx) FAST_FUNC;
void md5_hash(md5_ctx_t *ctx, const void *buffer, size_t len) FAST_FUNC;
void md5_end(md5_ctx_t *ctx, void *resbuf) FAST_FUNC;
unsigned md5_end(md5_ctx_t *ctx, void *resbuf) FAST_FUNC;
void sha1_begin(sha1_ctx_t *ctx) FAST_FUNC;
#define sha1_hash md5_hash
void sha1_end(sha1_ctx_t *ctx, void *resbuf) FAST_FUNC;
unsigned sha1_end(sha1_ctx_t *ctx, void *resbuf) FAST_FUNC;
void sha256_begin(sha256_ctx_t *ctx) FAST_FUNC;
#define sha256_hash md5_hash
#define sha256_end sha1_end
void sha512_begin(sha512_ctx_t *ctx) FAST_FUNC;
void sha512_hash(sha512_ctx_t *ctx, const void *buffer, size_t len) FAST_FUNC;
void sha512_end(sha512_ctx_t *ctx, void *resbuf) FAST_FUNC;
unsigned sha512_end(sha512_ctx_t *ctx, void *resbuf) FAST_FUNC;
void sha3_begin(sha3_ctx_t *ctx) FAST_FUNC;
void sha3_hash(sha3_ctx_t *ctx, const void *buffer, size_t len) FAST_FUNC;
void sha3_end(sha3_ctx_t *ctx, void *resbuf) FAST_FUNC;
unsigned sha3_end(sha3_ctx_t *ctx, void *resbuf) FAST_FUNC;
/* TLS benefits from knowing that sha1 and sha256 share these. Give them "agnostic" names too */
typedef struct md5_ctx_t md5sha_ctx_t;
#define md5sha_hash md5_hash
#define sha_end sha1_end
extern uint32_t *global_crc32_table;
uint32_t *crc32_filltable(uint32_t *tbl256, int endian) FAST_FUNC;

View File

@ -458,7 +458,7 @@ void FAST_FUNC md5_hash(md5_ctx_t *ctx, const void *buffer, size_t len)
* endian byte order, so that a byte-wise output yields to the wanted
* ASCII representation of the message digest.
*/
void FAST_FUNC md5_end(md5_ctx_t *ctx, void *resbuf)
unsigned FAST_FUNC md5_end(md5_ctx_t *ctx, void *resbuf)
{
/* MD5 stores total in LE, need to swap on BE arches: */
common64_end(ctx, /*swap_needed:*/ BB_BIG_ENDIAN);
@ -472,6 +472,7 @@ void FAST_FUNC md5_end(md5_ctx_t *ctx, void *resbuf)
}
memcpy(resbuf, ctx->hash, sizeof(ctx->hash[0]) * 4);
return sizeof(ctx->hash[0]) * 4;
}
@ -865,7 +866,7 @@ void FAST_FUNC sha512_hash(sha512_ctx_t *ctx, const void *buffer, size_t len)
#endif /* NEED_SHA512 */
/* Used also for sha256 */
void FAST_FUNC sha1_end(sha1_ctx_t *ctx, void *resbuf)
unsigned FAST_FUNC sha1_end(sha1_ctx_t *ctx, void *resbuf)
{
unsigned hash_size;
@ -879,11 +880,13 @@ void FAST_FUNC sha1_end(sha1_ctx_t *ctx, void *resbuf)
for (i = 0; i < hash_size; ++i)
ctx->hash[i] = SWAP_BE32(ctx->hash[i]);
}
memcpy(resbuf, ctx->hash, sizeof(ctx->hash[0]) * hash_size);
hash_size *= sizeof(ctx->hash[0]);
memcpy(resbuf, ctx->hash, hash_size);
return hash_size;
}
#if NEED_SHA512
void FAST_FUNC sha512_end(sha512_ctx_t *ctx, void *resbuf)
unsigned FAST_FUNC sha512_end(sha512_ctx_t *ctx, void *resbuf)
{
unsigned bufpos = ctx->total64[0] & 127;
@ -915,6 +918,7 @@ void FAST_FUNC sha512_end(sha512_ctx_t *ctx, void *resbuf)
ctx->hash[i] = SWAP_BE64(ctx->hash[i]);
}
memcpy(resbuf, ctx->hash, sizeof(ctx->hash));
return sizeof(ctx->hash);
}
#endif /* NEED_SHA512 */
@ -1450,7 +1454,7 @@ void FAST_FUNC sha3_hash(sha3_ctx_t *ctx, const void *buffer, size_t len)
#endif
}
void FAST_FUNC sha3_end(sha3_ctx_t *ctx, void *resbuf)
unsigned FAST_FUNC sha3_end(sha3_ctx_t *ctx, void *resbuf)
{
/* Padding */
uint8_t *buf = (uint8_t*)ctx->state;
@ -1475,4 +1479,5 @@ void FAST_FUNC sha3_end(sha3_ctx_t *ctx, void *resbuf)
/* Output */
memcpy(resbuf, ctx->state, 64);
return 64;
}

View File

@ -437,7 +437,7 @@ void FAST_FUNC md5_hash(const void *buffer, size_t inputLen, md5_ctx_t *context)
* MD5 finalization. Ends an MD5 message-digest operation,
* writing the message digest.
*/
void FAST_FUNC md5_end(void *digest, md5_ctx_t *context)
unsigned FAST_FUNC md5_end(void *digest, md5_ctx_t *context)
{
unsigned idx, padLen;
unsigned char bits[8];
@ -457,4 +457,5 @@ void FAST_FUNC md5_end(void *digest, md5_ctx_t *context)
/* Store state in digest */
memcpy32_cpu2le(digest, context->state, 16);
return 16;
}

View File

@ -18,9 +18,10 @@ static char *
NOINLINE
sha_crypt(/*const*/ char *key_data, /*const*/ char *salt_data)
{
#undef sha_end
void (*sha_begin)(void *ctx) FAST_FUNC;
void (*sha_hash)(void *ctx, const void *buffer, size_t len) FAST_FUNC;
void (*sha_end)(void *ctx, void *resbuf) FAST_FUNC;
unsigned (*sha_end)(void *ctx, void *resbuf) FAST_FUNC;
int _32or64;
char *result, *resptr;

View File

@ -18,10 +18,50 @@
#include "tls.h"
#define TLS_DEBUG 0
#define TLS_DEBUG_HASH 0
#define TLS_DEBUG_DER 0
#define TLS_DEBUG_FIXED_SECRETS 0
//Tested against kernel.org:
//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
//#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 *** select this?
// works against "openssl s_server -cipher NULL"
// and against wolfssl-3.9.10-stable/examples/server/server.c:
//#define CIPHER_ID TLS_RSA_WITH_NULL_SHA256 // for testing (does everything except encrypting)
// works against wolfssl-3.9.10-stable/examples/server/server.c
// works for kernel.org
// does not work for cdn.kernel.org (e.g. downloading an actual tarball, not a web page)
// 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 -no_tls1 -no_tls1_1 -cipher AES256-SHA256
// fail: openssl s_client -connect cdn.kernel.org:443 -debug -tls1_2 -no_tls1 -no_tls1_1 -cipher AES256-GCM-SHA384
// fail: openssl s_client -connect cdn.kernel.org:443 -debug -tls1_2 -no_tls1 -no_tls1_1 -cipher AES128-SHA256
// ok: openssl s_client -connect cdn.kernel.org:443 -debug -tls1_2 -no_tls1 -no_tls1_1 -cipher AES128-GCM-SHA256
// ok: openssl s_client -connect cdn.kernel.org:443 -debug -tls1_2 -no_tls1 -no_tls1_1 -cipher AES128-SHA
// (TLS_RSA_WITH_AES_128_CBC_SHA - in TLS 1.2 it's mandated to be always supported)
#define CIPHER_ID1 TLS_RSA_WITH_AES_256_CBC_SHA256 // no SERVER_KEY_EXCHANGE from peer
// Does not work yet:
//#define CIPHER_ID2 TLS_RSA_WITH_AES_128_CBC_SHA
#define CIPHER_ID2 0
#define TLS_DEBUG 1
#define TLS_DEBUG_HASH 1
#define TLS_DEBUG_DER 1
#define TLS_DEBUG_FIXED_SECRETS 1
#if 0
# define dump_raw_out(...) dump_hex(__VA_ARGS__)
#else
@ -124,52 +164,26 @@
#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 1.2
#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
//#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 *** select this?
// works against "openssl s_server -cipher NULL"
// and against wolfssl-3.9.10-stable/examples/server/server.c:
//#define CIPHER_ID TLS_RSA_WITH_NULL_SHA256 // for testing (does everything except encrypting)
// works against wolfssl-3.9.10-stable/examples/server/server.c
// works for kernel.org
// does not work for cdn.kernel.org (e.g. downloading an actual tarball, not a web page)
// 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 -no_tls1 -no_tls1_1 -cipher AES256-SHA256
// fail: openssl s_client -connect cdn.kernel.org:443 -debug -tls1_2 -no_tls1 -no_tls1_1 -cipher AES256-GCM-SHA384
// fail: openssl s_client -connect cdn.kernel.org:443 -debug -tls1_2 -no_tls1 -no_tls1_1 -cipher AES128-SHA256
// ok: openssl s_client -connect cdn.kernel.org:443 -debug -tls1_2 -no_tls1 -no_tls1_1 -cipher AES128-GCM-SHA256
// ok: openssl s_client -connect cdn.kernel.org:443 -debug -tls1_2 -no_tls1 -no_tls1_1 -cipher AES128-SHA
// (TLS_RSA_WITH_AES_128_CBC_SHA - in TLS 1.2 it's mandated to be always supported)
#define CIPHER_ID TLS_RSA_WITH_AES_256_CBC_SHA256 // no SERVER_KEY_EXCHANGE from peer
/* 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,
AES_BLOCKSIZE = 16,
AES128_KEYSIZE = 16,
AES256_KEYSIZE = 32,
RSA_PREMASTER_SIZE = 48,
RECHDR_LEN = 5,
MAX_TLS_RECORD = (1 << 14),
/* 8 = 3+5. 3 extra bytes result in record data being 32-bit aligned */
OUTBUF_PFX = 8 + AES_BLOCKSIZE, /* header + IV */
OUTBUF_SFX = SHA256_OUTSIZE + AES_BLOCKSIZE, /* MAC + padding */
MAX_OUTBUF = MAX_TLS_RECORD - OUTBUF_PFX - OUTBUF_SFX,
OUTBUF_SFX = TLS_MAX_MAC_SIZE + TLS_MAX_CRYPTBLOCK_SIZE, /* MAC + padding */
// RFC 5246
// | 6.2.1. Fragmentation
@ -205,7 +219,7 @@ enum {
// | length
// | The length (in bytes) of the following TLSCiphertext.fragment.
// | The length MUST NOT exceed 2^14 + 2048.
MAX_INBUF = (1 << 14) + 2048,
MAX_INBUF = RECHDR_LEN + (1 << 14) + 2048,
};
struct record_hdr {
@ -215,12 +229,17 @@ struct record_hdr {
};
struct tls_handshake_data {
sha256_ctx_t handshake_sha256_ctx;
/* In bbox, md5/sha1/sha256 ctx's are the same structure */
md5sha_ctx_t handshake_hash_ctx;
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;
unsigned saved_client_hello_size;
uint8_t saved_client_hello[1];
};
@ -275,37 +294,41 @@ void tls_get_random(void *buf, unsigned len)
xfunc_die();
}
//TODO rename this to sha256_hash, and sha256_hash -> sha256_update
static void hash_sha256(uint8_t out[SHA256_OUTSIZE], const void *data, unsigned size)
{
sha256_ctx_t ctx;
sha256_begin(&ctx);
sha256_hash(&ctx, data, size);
sha256_end(&ctx, out);
}
/* Nondestructively see the current hash value */
static void sha256_peek(sha256_ctx_t *ctx, void *buffer)
static unsigned sha_peek(md5sha_ctx_t *ctx, void *buffer)
{
sha256_ctx_t ctx_copy = *ctx;
sha256_end(&ctx_copy, buffer);
md5sha_ctx_t ctx_copy = *ctx; /* struct copy */
return sha_end(&ctx_copy, buffer);
}
#if TLS_DEBUG_HASH
static void sha256_hash_dbg(const char *fmt, sha256_ctx_t *ctx, const void *buffer, size_t len)
static ALWAYS_INLINE unsigned get_handshake_hash(tls_state_t *tls, void *buffer)
{
uint8_t h[SHA256_OUTSIZE];
sha256_hash(ctx, buffer, len);
dump_hex(fmt, buffer, len);
dbg(" (%u) ", (int)len);
sha256_peek(ctx, h);
dump_hex("%s\n", h, SHA256_OUTSIZE);
return sha_peek(&tls->hsd->handshake_hash_ctx, buffer);
}
#else
# define sha256_hash_dbg(fmt, ctx, buffer, len) \
sha256_hash(ctx, buffer, len)
#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 (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
}
// RFC 2104
// HMAC(key, text) based on a hash H (say, sha256) is:
@ -317,12 +340,13 @@ static void sha256_hash_dbg(const char *fmt, sha256_ctx_t *ctx, const void *buff
// if we often need HMAC hmac with the same key.
//
// text is often given in disjoint pieces.
static void hmac_sha256_precomputed_v(uint8_t out[SHA256_OUTSIZE],
sha256_ctx_t *hashed_key_xor_ipad,
sha256_ctx_t *hashed_key_xor_opad,
static unsigned hmac_sha_precomputed_v(uint8_t *out,
md5sha_ctx_t *hashed_key_xor_ipad,
md5sha_ctx_t *hashed_key_xor_opad,
va_list va)
{
uint8_t *text;
unsigned len;
/* hashed_key_xor_ipad contains unclosed "H((key XOR ipad) +" state */
/* hashed_key_xor_opad contains unclosed "H((key XOR opad) +" state */
@ -330,24 +354,24 @@ static void hmac_sha256_precomputed_v(uint8_t out[SHA256_OUTSIZE],
/* calculate out = H((key XOR ipad) + text) */
while ((text = va_arg(va, uint8_t*)) != NULL) {
unsigned text_size = va_arg(va, unsigned);
sha256_hash(hashed_key_xor_ipad, text, text_size);
md5sha_hash(hashed_key_xor_ipad, text, text_size);
}
sha256_end(hashed_key_xor_ipad, out);
len = sha_end(hashed_key_xor_ipad, out);
/* out = H((key XOR opad) + out) */
sha256_hash(hashed_key_xor_opad, out, SHA256_OUTSIZE);
sha256_end(hashed_key_xor_opad, out);
md5sha_hash(hashed_key_xor_opad, out, len);
return sha_end(hashed_key_xor_opad, out);
}
static void hmac_sha256(uint8_t out[SHA256_OUTSIZE], uint8_t *key, unsigned key_size, ...)
static unsigned hmac(tls_state_t *tls, uint8_t *out, uint8_t *key, unsigned key_size, ...)
{
sha256_ctx_t hashed_key_xor_ipad;
sha256_ctx_t hashed_key_xor_opad;
uint8_t key_xor_ipad[SHA256_INSIZE];
uint8_t key_xor_opad[SHA256_INSIZE];
md5sha_ctx_t hashed_key_xor_ipad;
md5sha_ctx_t hashed_key_xor_opad;
uint8_t key_xor_ipad[SHA_INSIZE];
uint8_t key_xor_opad[SHA_INSIZE];
uint8_t tempkey[SHA256_OUTSIZE];
va_list va;
int i;
unsigned i;
va_start(va, key_size);
@ -355,27 +379,38 @@ static void hmac_sha256(uint8_t out[SHA256_OUTSIZE], uint8_t *key, unsigned key_
// 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 > SHA256_INSIZE) {
hash_sha256(tempkey, key, key_size);
key = tempkey;
key_size = SHA256_OUTSIZE;
if (key_size > SHA_INSIZE) {
md5sha_ctx_t ctx;
if (tls->MAC_size == SHA256_OUTSIZE)
sha256_begin(&ctx);
else
sha1_begin(&ctx);
md5sha_hash(&ctx, key, key_size);
key_size = sha_end(&ctx, tempkey);
}
for (i = 0; i < key_size; i++) {
key_xor_ipad[i] = key[i] ^ 0x36;
key_xor_opad[i] = key[i] ^ 0x5c;
}
for (; i < SHA256_INSIZE; i++) {
for (; i < SHA_INSIZE; i++) {
key_xor_ipad[i] = 0x36;
key_xor_opad[i] = 0x5c;
}
sha256_begin(&hashed_key_xor_ipad);
sha256_hash(&hashed_key_xor_ipad, key_xor_ipad, SHA256_INSIZE);
sha256_begin(&hashed_key_xor_opad);
sha256_hash(&hashed_key_xor_opad, key_xor_opad, SHA256_INSIZE);
hmac_sha256_precomputed_v(out, &hashed_key_xor_ipad, &hashed_key_xor_opad, va);
if (tls->MAC_size == SHA256_OUTSIZE) {
sha256_begin(&hashed_key_xor_ipad);
sha256_begin(&hashed_key_xor_opad);
} else {
sha1_begin(&hashed_key_xor_ipad);
sha1_begin(&hashed_key_xor_opad);
}
md5sha_hash(&hashed_key_xor_ipad, key_xor_ipad, SHA_INSIZE);
md5sha_hash(&hashed_key_xor_opad, key_xor_opad, SHA_INSIZE);
i = hmac_sha_precomputed_v(out, &hashed_key_xor_ipad, &hashed_key_xor_opad, va);
va_end(va);
return i;
}
// RFC 5246:
@ -406,40 +441,41 @@ static void hmac_sha256(uint8_t out[SHA256_OUTSIZE], uint8_t *key, unsigned key_
// PRF(secret, label, seed) = P_<hash>(secret, label + seed)
//
// The label is an ASCII string.
static void prf_hmac_sha256(
static void prf_hmac(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)
{
uint8_t a[SHA256_OUTSIZE];
uint8_t a[TLS_MAX_MAC_SIZE];
uint8_t *out_p = outbuf;
unsigned label_size = strlen(label);
unsigned MAC_size = tls->MAC_size;
/* In P_hash() calculation, "seed" is "label + seed": */
#define SEED label, label_size, seed, seed_size
#define SECRET secret, secret_size
#define A a, (int)(sizeof(a))
#define A a, MAC_size
/* A(1) = HMAC_hash(secret, seed) */
hmac_sha256(a, SECRET, SEED, NULL);
//TODO: convert hmac_sha256 to precomputed
hmac(tls, a, SECRET, SEED, NULL);
//TODO: convert hmac to precomputed
for(;;) {
/* HMAC_hash(secret, A(1) + seed) */
if (outbuf_size <= SHA256_OUTSIZE) {
if (outbuf_size <= MAC_size) {
/* Last, possibly incomplete, block */
/* (use a[] as temp buffer) */
hmac_sha256(a, SECRET, A, SEED, NULL);
hmac(tls, a, SECRET, A, SEED, NULL);
memcpy(out_p, a, outbuf_size);
return;
}
/* Not last block. Store directly to result buffer */
hmac_sha256(out_p, SECRET, A, SEED, NULL);
out_p += SHA256_OUTSIZE;
outbuf_size -= SHA256_OUTSIZE;
hmac(tls, out_p, SECRET, A, SEED, NULL);
out_p += MAC_size;
outbuf_size -= MAC_size;
/* A(2) = HMAC_hash(secret, A(1)) */
hmac_sha256(a, SECRET, A, NULL);
hmac(tls, a, SECRET, A, NULL);
}
#undef A
#undef SECRET
@ -484,11 +520,12 @@ static void tls_free_outbuf(tls_state_t *tls)
static void *tls_get_outbuf(tls_state_t *tls, int len)
{
if (len > MAX_OUTBUF)
if (len > TLS_MAX_OUTBUF)
xfunc_die();
if (tls->outbuf_size < len + OUTBUF_PFX + OUTBUF_SFX) {
tls->outbuf_size = len + OUTBUF_PFX + OUTBUF_SFX;
tls->outbuf = xrealloc(tls->outbuf, tls->outbuf_size);
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;
}
@ -500,7 +537,7 @@ static void xwrite_encrypted(tls_state_t *tls, unsigned size, unsigned type)
uint8_t padding_length;
xhdr = (void*)(buf - RECHDR_LEN);
if (CIPHER_ID != TLS_RSA_WITH_NULL_SHA256)
if (tls->cipher_id != TLS_RSA_WITH_NULL_SHA256)
xhdr = (void*)(buf - RECHDR_LEN - AES_BLOCKSIZE); /* place for IV */
xhdr->type = type;
@ -511,16 +548,16 @@ static void xwrite_encrypted(tls_state_t *tls, unsigned size, unsigned type)
xhdr->len16_lo = size & 0xff;
/* Calculate MAC signature */
//TODO: convert hmac_sha256 to precomputed
hmac_sha256(buf + size,
tls->client_write_MAC_key, sizeof(tls->client_write_MAC_key),
hmac(tls, buf + size, /* result */
tls->client_write_MAC_key, tls->MAC_size,
&tls->write_seq64_be, sizeof(tls->write_seq64_be),
xhdr, RECHDR_LEN,
buf, size,
NULL);
NULL
);
tls->write_seq64_be = SWAP_BE64(1 + SWAP_BE64(tls->write_seq64_be));
size += SHA256_OUTSIZE;
size += tls->MAC_size;
// RFC 5246
// 6.2.3.1. Null or Standard Stream Cipher
@ -555,7 +592,7 @@ static void xwrite_encrypted(tls_state_t *tls, unsigned size, unsigned type)
// -------- ----------- ---------- --------------
// SHA HMAC-SHA1 20 20
// SHA256 HMAC-SHA256 32 32
if (CIPHER_ID == TLS_RSA_WITH_NULL_SHA256) {
if (tls->cipher_id == TLS_RSA_WITH_NULL_SHA256) {
/* No encryption, only signing */
xhdr->len16_hi = size >> 8;
xhdr->len16_lo = size & 0xff;
@ -603,7 +640,7 @@ static void xwrite_encrypted(tls_state_t *tls, unsigned size, unsigned type)
/* Fill IV and padding in outbuf */
tls_get_random(buf - AES_BLOCKSIZE, AES_BLOCKSIZE); /* IV */
dbg("before crypt: 5 hdr + %u data + %u hash bytes\n", size, SHA256_OUTSIZE);
dbg("before crypt: 5 hdr + %u data + %u hash bytes\n", size, tls->MAC_size);
// 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."
@ -628,7 +665,7 @@ static void xwrite_encrypted(tls_state_t *tls, unsigned size, unsigned type)
{
psCipherContext_t ctx;
psAesInit(&ctx, buf - AES_BLOCKSIZE, /* IV */
tls->client_write_key, sizeof(tls->client_write_key)
tls->client_write_key, tls->key_size /* selects 128/256 */
);
psAesEncrypt(&ctx,
buf, /* plaintext */
@ -648,9 +685,9 @@ static void xwrite_encrypted(tls_state_t *tls, unsigned size, unsigned type)
dbg("wrote %u bytes\n", (int)RECHDR_LEN + size);
}
static void xwrite_and_update_handshake_hash(tls_state_t *tls, unsigned size)
static void xwrite_handshake_record(tls_state_t *tls, unsigned size)
{
if (!tls->encrypt_on_write) {
//if (!tls->encrypt_on_write) {
uint8_t *buf = tls->outbuf + OUTBUF_PFX;
struct record_hdr *xhdr = (void*)(buf - RECHDR_LEN);
@ -662,8 +699,20 @@ static void xwrite_and_update_handshake_hash(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)
{
if (!tls->encrypt_on_write) {
uint8_t *buf;
xwrite_handshake_record(tls, size);
/* Handshake hash does not include record headers */
sha256_hash_dbg(">> sha256:%s", &tls->hsd->handshake_sha256_ctx, buf, size);
buf = tls->outbuf + OUTBUF_PFX;
hash_handshake(tls, ">> hash:%s", buf, size);
return;
}
xwrite_encrypted(tls, size, RECORD_TYPE_HANDSHAKE);
@ -765,7 +814,7 @@ static int tls_xread_record(tls_state_t *tls)
sz = target - RECHDR_LEN;
/* Needs to be decrypted? */
if (tls->min_encrypted_len_on_read > SHA256_OUTSIZE) {
if (tls->min_encrypted_len_on_read > tls->MAC_size) {
psCipherContext_t ctx;
uint8_t *p = tls->inbuf + RECHDR_LEN;
int padding_len;
@ -777,7 +826,7 @@ static int tls_xread_record(tls_state_t *tls)
}
/* Decrypt content+MAC+padding, moving it over IV in the process */
psAesInit(&ctx, p, /* IV */
tls->server_write_key, sizeof(tls->server_write_key)
tls->server_write_key, tls->key_size /* selects 128/256 */
);
sz -= AES_BLOCKSIZE; /* we will overwrite IV now */
psAesDecrypt(&ctx,
@ -788,7 +837,7 @@ static int tls_xread_record(tls_state_t *tls)
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 -= SHA256_OUTSIZE + padding_len; /* drop MAC and padding */
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 {
@ -834,8 +883,10 @@ static int tls_xread_record(tls_state_t *tls)
/* 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) {
sha256_hash_dbg("<< sha256:%s", &tls->hsd->handshake_sha256_ctx, tls->inbuf + RECHDR_LEN, sz);
if (tls->inbuf[0] == RECORD_TYPE_HANDSHAKE
&& tls->MAC_size != 0 /* do we know which hash to use? (server_hello() does not!) */
) {
hash_handshake(tls, "<< hash:%s", tls->inbuf + RECHDR_LEN, sz);
}
end:
dbg("got block len:%u\n", sz);
@ -1088,7 +1139,7 @@ static ALWAYS_INLINE void fill_handshake_record_hdr(void *buf, unsigned type, un
h->len24_lo = len & 0xff;
}
static void send_client_hello(tls_state_t *tls, const char *sni)
static void send_client_hello_and_alloc_hsd(tls_state_t *tls, const char *sni)
{
struct client_hello {
uint8_t type;
@ -1098,7 +1149,7 @@ static void send_client_hello(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]; /* actually variable */
uint8_t cipherid[2 * (2 + !!CIPHER_ID2)]; /* actually variable */
uint8_t comprtypes_len;
uint8_t comprtypes[1]; /* actually variable */
/* Extensions (SNI shown):
@ -1136,17 +1187,19 @@ static void send_client_hello(tls_state_t *tls, const char *sni)
tls_get_random(record->rand32, sizeof(record->rand32));
if (TLS_DEBUG_FIXED_SECRETS)
memset(record->rand32, 0x11, sizeof(record->rand32));
memcpy(tls->hsd->client_and_server_rand32, record->rand32, sizeof(record->rand32));
/* record->session_id_len = 0; - already is */
/* record->cipherid_len16_hi = 0; */
record->cipherid_len16_lo = 2 * 2;
if ((CIPHER_ID >> 8) != 0)
record->cipherid[0] = CIPHER_ID >> 8;
record->cipherid[1] = CIPHER_ID & 0xff;
record->cipherid_len16_lo = sizeof(record->cipherid);
/* RFC 5746 Renegotiation Indication Extension - some servers will refuse to work with us otherwise */
/*record->cipherid[2] = TLS_EMPTY_RENEGOTIATION_INFO_SCSV >> 8; - zero */
record->cipherid[3] = TLS_EMPTY_RENEGOTIATION_INFO_SCSV & 0xff;
/*record->cipherid[0] = TLS_EMPTY_RENEGOTIATION_INFO_SCSV >> 8; - zero */
record->cipherid[1] = TLS_EMPTY_RENEGOTIATION_INFO_SCSV & 0xff;
if ((CIPHER_ID1 >> 8) != 0) record->cipherid[2] = CIPHER_ID1 >> 8;
/*************************/ record->cipherid[3] = CIPHER_ID1 & 0xff;
#if CIPHER_ID2
if ((CIPHER_ID2 >> 8) != 0) record->cipherid[4] = CIPHER_ID2 >> 8;
/*************************/ record->cipherid[5] = CIPHER_ID2 & 0xff;
#endif
record->comprtypes_len = 1;
/* record->comprtypes[0] = 0; */
@ -1168,7 +1221,14 @@ static void send_client_hello(tls_state_t *tls, const char *sni)
}
dbg(">> CLIENT_HELLO\n");
xwrite_and_update_handshake_hash(tls, len);
/* 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->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));
}
static void get_server_hello(tls_state_t *tls)
@ -1188,7 +1248,8 @@ static void get_server_hello(tls_state_t *tls)
struct server_hello *hp;
uint8_t *cipherid;
int len;
unsigned cipher;
int len, len24;
len = tls_xread_handshake_block(tls, 74);
@ -1207,6 +1268,7 @@ static void get_server_hello(tls_state_t *tls)
}
cipherid = &hp->cipherid_hi;
len24 = hp->len24_lo;
if (hp->session_id_len != 32) {
if (hp->session_id_len != 0)
tls_error_die(tls);
@ -1216,19 +1278,39 @@ static void get_server_hello(tls_state_t *tls)
// may return an empty session_id to indicate that the session will
// not be cached and therefore cannot be resumed."
cipherid -= 32;
hp->len24_lo += 32; /* what len would be if session id would be present */
len24 += 32; /* what len would be if session id would be present */
}
if (hp->len24_lo < 70
|| cipherid[0] != (CIPHER_ID >> 8)
|| cipherid[1] != (CIPHER_ID & 0xff)
|| cipherid[2] != 0 /* comprtype */
if (len24 < 70
// || cipherid[0] != (CIPHER_ID >> 8)
// || cipherid[1] != (CIPHER_ID & 0xff)
// || cipherid[2] != 0 /* comprtype */
) {
tls_error_die(tls);
}
dbg("<< SERVER_HELLO\n");
memcpy(tls->hsd->client_and_server_rand32 + 32, hp->rand32, sizeof(hp->rand32));
tls->cipher_id = cipher = 0x100 * cipherid[0] + cipherid[1];
dbg("server chose cipher %04x\n", cipher);
if (cipher == TLS_RSA_WITH_AES_128_CBC_SHA) {
tls->key_size = AES128_KEYSIZE;
tls->MAC_size = SHA1_OUTSIZE;
sha1_begin(&tls->hsd->handshake_hash_ctx);
}
else { /* TLS_RSA_WITH_AES_256_CBC_SHA256 */
tls->key_size = AES256_KEYSIZE;
tls->MAC_size = SHA256_OUTSIZE;
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)
@ -1312,7 +1394,7 @@ static void send_client_key_exchange(tls_state_t *tls)
// [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(
prf_hmac(tls,
tls->hsd->master_secret, sizeof(tls->hsd->master_secret),
rsa_premaster, sizeof(rsa_premaster),
"master secret",
@ -1360,21 +1442,23 @@ static void send_client_key_exchange(tls_state_t *tls)
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->client_write_MAC_key, 2 * (SHA256_OUTSIZE + AES256_KEYSIZE),
prf_hmac(tls,
tls->client_write_MAC_key, 2 * (tls->MAC_size + tls->key_size),
// also fills:
// server_write_MAC_key[SHA256_OUTSIZE]
// client_write_key[AES256_KEYSIZE]
// server_write_key[AES256_KEYSIZE]
// server_write_MAC_key[]
// client_write_key[]
// server_write_key[]
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;
dump_hex("client_write_MAC_key:%s\n",
tls->client_write_MAC_key, sizeof(tls->client_write_MAC_key)
tls->client_write_MAC_key, tls->MAC_size
);
dump_hex("client_write_key:%s\n",
tls->client_write_key, sizeof(tls->client_write_key)
tls->client_write_key, tls->key_size
);
}
}
@ -1435,15 +1519,17 @@ static void send_client_finished(tls_state_t *tls)
uint8_t prf_result[12];
};
struct finished *record = tls_get_outbuf(tls, sizeof(*record));
uint8_t handshake_hash[SHA256_OUTSIZE];
uint8_t handshake_hash[TLS_MAX_MAC_SIZE];
unsigned len;
fill_handshake_record_hdr(record, HANDSHAKE_FINISHED, sizeof(*record));
sha256_peek(&tls->hsd->handshake_sha256_ctx, handshake_hash);
prf_hmac_sha256(record->prf_result, sizeof(record->prf_result),
len = get_handshake_hash(tls, handshake_hash);
prf_hmac(tls,
record->prf_result, sizeof(record->prf_result),
tls->hsd->master_secret, sizeof(tls->hsd->master_secret),
"client finished",
handshake_hash, sizeof(handshake_hash)
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);
@ -1475,10 +1561,7 @@ void FAST_FUNC tls_handshake(tls_state_t *tls, const char *sni)
// Application Data <------> Application Data
int len;
tls->hsd = xzalloc(sizeof(*tls->hsd));
sha256_begin(&tls->hsd->handshake_sha256_ctx);
send_client_hello(tls, sni);
send_client_hello_and_alloc_hsd(tls, sni);
get_server_hello(tls);
// RFC 5246
@ -1535,11 +1618,11 @@ void FAST_FUNC tls_handshake(tls_state_t *tls, const char *sni)
if (len != 1 || memcmp(tls->inbuf, rec_CHANGE_CIPHER_SPEC, 6) != 0)
tls_error_die(tls);
dbg("<< CHANGE_CIPHER_SPEC\n");
if (CIPHER_ID == TLS_RSA_WITH_NULL_SHA256)
tls->min_encrypted_len_on_read = SHA256_OUTSIZE;
if (tls->cipher_id == TLS_RSA_WITH_NULL_SHA256)
tls->min_encrypted_len_on_read = tls->MAC_size;
else
/* all incoming packets now should be encrypted and have IV + MAC + padding */
tls->min_encrypted_len_on_read = AES_BLOCKSIZE + SHA256_OUTSIZE + AES_BLOCKSIZE;
tls->min_encrypted_len_on_read = AES_BLOCKSIZE + tls->MAC_size + AES_BLOCKSIZE;
/* Get (encrypted) FINISHED from the server */
len = tls_xread_record(tls);
@ -1550,7 +1633,7 @@ void FAST_FUNC tls_handshake(tls_state_t *tls, const char *sni)
/* free handshake data */
// if (PARANOIA)
// memset(tls->hsd, 0, sizeof(*tls->hsd));
// memset(tls->hsd, 0, tls->hsd->hsd_size);
free(tls->hsd);
tls->hsd = NULL;
}
@ -1614,8 +1697,8 @@ void FAST_FUNC tls_run_copy_loop(tls_state_t *tls)
* read, encrypt and send bigger chunks
*/
inbuf_size += INBUF_STEP;
if (inbuf_size > MAX_OUTBUF)
inbuf_size = MAX_OUTBUF;
if (inbuf_size > TLS_MAX_OUTBUF)
inbuf_size = TLS_MAX_OUTBUF;
}
tls_xwrite(tls, nread);
}