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Diffstat (limited to 'openssl/crypto/bn')
-rw-r--r--openssl/crypto/bn/asm/x86_64-gcc.c8
-rw-r--r--openssl/crypto/bn/bn_exp.c9
-rw-r--r--openssl/crypto/bn/bn_nist.c6
-rw-r--r--openssl/crypto/bn/exptest.c45
4 files changed, 59 insertions, 9 deletions
diff --git a/openssl/crypto/bn/asm/x86_64-gcc.c b/openssl/crypto/bn/asm/x86_64-gcc.c
index acb0b4011..31476abeb 100644
--- a/openssl/crypto/bn/asm/x86_64-gcc.c
+++ b/openssl/crypto/bn/asm/x86_64-gcc.c
@@ -189,7 +189,7 @@ BN_ULONG bn_add_words (BN_ULONG *rp, const BN_ULONG *ap, const BN_ULONG *bp,int
if (n <= 0) return 0;
- asm (
+ asm volatile (
" subq %2,%2 \n"
".p2align 4 \n"
"1: movq (%4,%2,8),%0 \n"
@@ -200,7 +200,7 @@ BN_ULONG bn_add_words (BN_ULONG *rp, const BN_ULONG *ap, const BN_ULONG *bp,int
" sbbq %0,%0 \n"
: "=&a"(ret),"+c"(n),"=&r"(i)
: "r"(rp),"r"(ap),"r"(bp)
- : "cc"
+ : "cc", "memory"
);
return ret&1;
@@ -212,7 +212,7 @@ BN_ULONG bn_sub_words (BN_ULONG *rp, const BN_ULONG *ap, const BN_ULONG *bp,int
if (n <= 0) return 0;
- asm (
+ asm volatile (
" subq %2,%2 \n"
".p2align 4 \n"
"1: movq (%4,%2,8),%0 \n"
@@ -223,7 +223,7 @@ BN_ULONG bn_sub_words (BN_ULONG *rp, const BN_ULONG *ap, const BN_ULONG *bp,int
" sbbq %0,%0 \n"
: "=&a"(ret),"+c"(n),"=&r"(i)
: "r"(rp),"r"(ap),"r"(bp)
- : "cc"
+ : "cc", "memory"
);
return ret&1;
diff --git a/openssl/crypto/bn/bn_exp.c b/openssl/crypto/bn/bn_exp.c
index 5e7eb3373..611fa3262 100644
--- a/openssl/crypto/bn/bn_exp.c
+++ b/openssl/crypto/bn/bn_exp.c
@@ -874,7 +874,14 @@ int BN_mod_exp_mont_word(BIGNUM *rr, BN_ULONG a, const BIGNUM *p,
bits = BN_num_bits(p);
if (bits == 0)
{
- ret = BN_one(rr);
+ /* x**0 mod 1 is still zero. */
+ if (BN_is_one(m))
+ {
+ ret = 1;
+ BN_zero(rr);
+ }
+ else
+ ret = BN_one(rr);
return ret;
}
if (a == 0)
diff --git a/openssl/crypto/bn/bn_nist.c b/openssl/crypto/bn/bn_nist.c
index e22968d4a..abb157085 100644
--- a/openssl/crypto/bn/bn_nist.c
+++ b/openssl/crypto/bn/bn_nist.c
@@ -1088,9 +1088,9 @@ int BN_nist_mod_521(BIGNUM *r, const BIGNUM *a, const BIGNUM *field,
/* ... and right shift */
for (val=t_d[0],i=0; i<BN_NIST_521_TOP-1; i++)
{
- tmp = val>>BN_NIST_521_RSHIFT;
- val = t_d[i+1];
- t_d[i] = (tmp | val<<BN_NIST_521_LSHIFT) & BN_MASK2;
+ t_d[i] = ( val>>BN_NIST_521_RSHIFT |
+ (tmp=t_d[i+1])<<BN_NIST_521_LSHIFT ) & BN_MASK2;
+ val=tmp;
}
t_d[i] = val>>BN_NIST_521_RSHIFT;
/* lower 521 bits */
diff --git a/openssl/crypto/bn/exptest.c b/openssl/crypto/bn/exptest.c
index 074a8e882..5fa02a122 100644
--- a/openssl/crypto/bn/exptest.c
+++ b/openssl/crypto/bn/exptest.c
@@ -71,6 +71,43 @@
static const char rnd_seed[] = "string to make the random number generator think it has entropy";
+/* test_exp_mod_zero tests that x**0 mod 1 == 0. It returns zero on success. */
+static int test_exp_mod_zero() {
+ BIGNUM a, p, m;
+ BIGNUM r;
+ BN_CTX *ctx = BN_CTX_new();
+ int ret = 1;
+
+ BN_init(&m);
+ BN_one(&m);
+
+ BN_init(&a);
+ BN_one(&a);
+
+ BN_init(&p);
+ BN_zero(&p);
+
+ BN_init(&r);
+ BN_mod_exp(&r, &a, &p, &m, ctx);
+ BN_CTX_free(ctx);
+
+ if (BN_is_zero(&r))
+ ret = 0;
+ else
+ {
+ printf("1**0 mod 1 = ");
+ BN_print_fp(stdout, &r);
+ printf(", should be 0\n");
+ }
+
+ BN_free(&r);
+ BN_free(&a);
+ BN_free(&p);
+ BN_free(&m);
+
+ return ret;
+}
+
int main(int argc, char *argv[])
{
BN_CTX *ctx;
@@ -190,7 +227,13 @@ int main(int argc, char *argv[])
ERR_remove_thread_state(NULL);
CRYPTO_mem_leaks(out);
BIO_free(out);
- printf(" done\n");
+ printf("\n");
+
+ if (test_exp_mod_zero() != 0)
+ goto err;
+
+ printf("done\n");
+
EXIT(0);
err:
ERR_load_crypto_strings();