Add FUZZING support to ssh.c.

[PuTTY.git] / sshccp.c

diff --git a/sshccp.c b/sshccp.c
index 71fde427e058d7c4d1bb3499c79a0f657d7255cb..0b3dc5737c1babe3e4640a42329ef03e8939b356 100644 (file)
--- a/sshccp.c
+++ b/sshccp.c
@@ -215,7 +215,23 @@ static void bigval_export_le(const bigval *r, void *vdata, int len)
  */
 static void bigval_add(bigval *r, const bigval *a, const bigval *b)
 {
-#if BIGNUM_INT_BITS == 32
+#if BIGNUM_INT_BITS == 64
+    /* ./contrib/make1305.py add 64 */
+    BignumDblInt acclo;
+    acclo = 0;
+    acclo += a->w[0];
+    acclo += b->w[0];
+    r->w[0] = acclo;
+    acclo >>= 64;
+    acclo += a->w[1];
+    acclo += b->w[1];
+    r->w[1] = acclo;
+    acclo >>= 64;
+    acclo += a->w[2];
+    acclo += b->w[2];
+    r->w[2] = acclo;
+    acclo >>= 64;
+#elif BIGNUM_INT_BITS == 32
     /* ./contrib/make1305.py add 32 */
     BignumDblInt acclo;
     acclo = 0;
@@ -290,7 +306,84 @@ static void bigval_add(bigval *r, const bigval *a, const bigval *b)
  */
 static void bigval_mul_mod_p(bigval *r, const bigval *a, const bigval *b)
 {
-#if BIGNUM_INT_BITS == 32
+#if BIGNUM_INT_BITS == 64
+    /* ./contrib/make1305.py mul 64 */
+    BignumDblInt tmp;
+    BignumDblInt acclo;
+    BignumDblInt acchi;
+    BignumDblInt acc2lo;
+    acclo = 0;
+    acchi = 0;
+    tmp = (BignumDblInt)(a->w[0]) * (b->w[0]);
+    acclo += tmp & BIGNUM_INT_MASK;
+    acchi += tmp >> 64;
+    r->w[0] = acclo;
+    acclo = acchi + (acclo >> 64);
+    acchi = 0;
+    tmp = (BignumDblInt)(a->w[0]) * (b->w[1]);
+    acclo += tmp & BIGNUM_INT_MASK;
+    acchi += tmp >> 64;
+    tmp = (BignumDblInt)(a->w[1]) * (b->w[0]);
+    acclo += tmp & BIGNUM_INT_MASK;
+    acchi += tmp >> 64;
+    r->w[1] = acclo;
+    acclo = acchi + (acclo >> 64);
+    acchi = 0;
+    tmp = (BignumDblInt)(a->w[0]) * (b->w[2]);
+    acclo += tmp & BIGNUM_INT_MASK;
+    acchi += tmp >> 64;
+    tmp = (BignumDblInt)(a->w[1]) * (b->w[1]);
+    acclo += tmp & BIGNUM_INT_MASK;
+    acchi += tmp >> 64;
+    tmp = (BignumDblInt)(a->w[2]) * (b->w[0]);
+    acclo += tmp & BIGNUM_INT_MASK;
+    acchi += tmp >> 64;
+    r->w[2] = acclo & (((BignumInt)1 << 2)-1);
+    acc2lo = 0;
+    acc2lo += ((acclo >> 2) & (((BignumInt)1 << 62)-1)) * ((BignumDblInt)5 << 0);
+    acclo = acchi + (acclo >> 64);
+    acchi = 0;
+    tmp = (BignumDblInt)(a->w[1]) * (b->w[2]);
+    acclo += tmp & BIGNUM_INT_MASK;
+    acchi += tmp >> 64;
+    tmp = (BignumDblInt)(a->w[2]) * (b->w[1]);
+    acclo += tmp & BIGNUM_INT_MASK;
+    acchi += tmp >> 64;
+    acc2lo += (acclo & (((BignumInt)1 << 2)-1)) * ((BignumDblInt)5 << 62);
+    acc2lo += r->w[0];
+    r->w[0] = acc2lo;
+    acc2lo >>= 64;
+    acc2lo += ((acclo >> 2) & (((BignumInt)1 << 62)-1)) * ((BignumDblInt)5 << 0);
+    acclo = acchi + (acclo >> 64);
+    acchi = 0;
+    tmp = (BignumDblInt)(a->w[2]) * (b->w[2]);
+    acclo += tmp & BIGNUM_INT_MASK;
+    acchi += tmp >> 64;
+    acc2lo += (acclo & (((BignumInt)1 << 2)-1)) * ((BignumDblInt)5 << 62);
+    acc2lo += r->w[1];
+    r->w[1] = acc2lo;
+    acc2lo >>= 64;
+    acc2lo += ((acclo >> 2) & (((BignumInt)1 << 2)-1)) * ((BignumDblInt)5 << 0);
+    acc2lo += r->w[2];
+    r->w[2] = acc2lo;
+    acc2lo = 0;
+    acc2lo += ((acclo >> 4) & (((BignumInt)1 << 60)-1)) * ((BignumDblInt)25 << 0);
+    acclo = acchi + (acclo >> 64);
+    acchi = 0;
+    acc2lo += (acclo & (((BignumInt)1 << 4)-1)) * ((BignumDblInt)25 << 60);
+    acc2lo += r->w[0];
+    r->w[0] = acc2lo;
+    acc2lo >>= 64;
+    acc2lo += ((acclo >> 4) & (((BignumInt)1 << 60)-1)) * ((BignumDblInt)25 << 0);
+    acclo = acchi + (acclo >> 64);
+    acchi = 0;
+    acc2lo += r->w[1];
+    r->w[1] = acc2lo;
+    acc2lo >>= 64;
+    acc2lo += r->w[2];
+    r->w[2] = acc2lo;
+    acc2lo >>= 64;
+#elif BIGNUM_INT_BITS == 32
     /* ./contrib/make1305.py mul 32 */
     BignumDblInt tmp;
     BignumDblInt acclo;
@@ -819,7 +912,28 @@ static void bigval_mul_mod_p(bigval *r, const bigval *a, const bigval *b)
 
 static void bigval_final_reduce(bigval *n)
 {
-#if BIGNUM_INT_BITS == 32
+#if BIGNUM_INT_BITS == 64
+    /* ./contrib/make1305.py final_reduce 64 */
+    BignumDblInt acclo;
+    acclo = 0;
+    acclo += 5 * ((n->w[2] >> 2) + 1);
+    acclo += n->w[0];
+    acclo >>= 64;
+    acclo += n->w[1];
+    acclo >>= 64;
+    acclo += n->w[2];
+    acclo = 5 * (acclo >> 2);
+    acclo += n->w[0];
+    n->w[0] = acclo;
+    acclo >>= 64;
+    acclo += n->w[1];
+    n->w[1] = acclo;
+    acclo >>= 64;
+    acclo += n->w[2];
+    n->w[2] = acclo;
+    acclo >>= 64;
+    n->w[2] &= (1 << 2) - 1;
+#elif BIGNUM_INT_BITS == 32
     /* ./contrib/make1305.py final_reduce 32 */
     BignumDblInt acclo;
     acclo = 0;
@@ -1124,7 +1238,7 @@ static const struct ssh_mac ssh2_poly1305 = {
     poly_start, poly_bytes, poly_genresult, poly_verresult,
 
     "", "", /* Not selectable individually, just part of ChaCha20-Poly1305 */
-    16, "Poly1305"
+    16, 0, "Poly1305"
 };
 
 static void *ccp_make_context(void)
@@ -1176,7 +1290,11 @@ static void ccp_length_op(struct ccp_context *ctx, unsigned char *blk, int len,
                           unsigned long seq)
 {
     unsigned char iv[8];
-    PUT_32BIT_LSB_FIRST(iv, seq >> 32);
+    /*
+     * According to RFC 4253 (section 6.4), the packet sequence number wraps
+     * at 2^32, so its 32 high-order bits will always be zero.
+     */
+    PUT_32BIT_LSB_FIRST(iv, 0);
     PUT_32BIT_LSB_FIRST(iv + 4, seq);
     chacha20_iv(&ctx->a_cipher, iv);
     chacha20_iv(&ctx->b_cipher, iv);
@@ -1213,7 +1331,7 @@ static const struct ssh2_cipher ssh2_chacha20_poly1305 = {
     ccp_decrypt_length,
 
     "chacha20-poly1305@openssh.com",
-    1, 512, SSH_CIPHER_SEPARATE_LENGTH, "ChaCha20",
+    1, 512, 64, SSH_CIPHER_SEPARATE_LENGTH, "ChaCha20",
 
     &ssh2_poly1305
 };