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Remove the last lingering knowledge, outside sshbn.c, of the

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internal structure of the Bignum type. Bignum is now a fully opaque
type unless you're inside sshbn.c.

[originally from svn r960]
This commit is contained in:
Simon Tatham
2001-03-01 17:41:26 +00:00
parent 7717c386a1
commit f72b5aa95f
7 changed files with 160 additions and 165 deletions
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29
sshrsa.c
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@ -48,7 +48,7 @@ int makeprivate(unsigned char *data, struct RSAKey *result) {
void rsaencrypt(unsigned char *data, int length, struct RSAKey *key) {
Bignum b1, b2;
int w, i;
int i;
unsigned char *p;
memmove(data+key->bytes-length, data, length);
@ -62,31 +62,13 @@ void rsaencrypt(unsigned char *data, int length, struct RSAKey *key) {
}
data[key->bytes-length-1] = 0;
w = (key->bytes+1)/2;
b1 = newbn(w);
p = data;
for (i=1; i<=w; i++)
b1[i] = 0;
for (i=key->bytes; i-- ;) {
unsigned char byte = *p++;
if (i & 1)
b1[1+i/2] |= byte<<8;
else
b1[1+i/2] |= byte;
}
b1 = bignum_from_bytes(data, key->bytes);
b2 = modpow(b1, key->exponent, key->modulus);
p = data;
for (i=key->bytes; i-- ;) {
unsigned char b;
if (i & 1)
b = b2[1+i/2] >> 8;
else
b = b2[1+i/2] & 0xFF;
*p++ = b;
*p++ = bignum_byte(b2, i);
}
freebn(b1);
@ -101,10 +83,13 @@ Bignum rsadecrypt(Bignum input, struct RSAKey *key) {
int rsastr_len(struct RSAKey *key) {
Bignum md, ex;
int mdlen, exlen;
md = key->modulus;
ex = key->exponent;
return 4 * (ex[0]+md[0]) + 20;
mdlen = (ssh1_bignum_bitcount(md)+15) / 16;
exlen = (ssh1_bignum_bitcount(ex)+15) / 16;
return 4 * (mdlen+exlen) + 20;
}
void rsastr_fmt(char *str, struct RSAKey *key) {