return b;
}
-static Bignum dss_p, dss_q, dss_g, dss_y;
+struct dss_key {
+ Bignum p, q, g, y;
+};
-static void dss_setkey(char *data, int len) {
+static void *dss_newkey(char *data, int len) {
char *p;
int slen;
+ struct dss_key *dss;
+
+ dss = smalloc(sizeof(struct dss_key));
+ if (!dss) return NULL;
getstring(&data, &len, &p, &slen);
#ifdef DEBUG_DSS
#endif
if (!p || memcmp(p, "ssh-dss", 7)) {
- dss_p = NULL;
- return;
+ sfree(dss);
+ return NULL;
}
- dss_p = getmp(&data, &len);
- dss_q = getmp(&data, &len);
- dss_g = getmp(&data, &len);
- dss_y = getmp(&data, &len);
+ dss->p = getmp(&data, &len);
+ dss->q = getmp(&data, &len);
+ dss->g = getmp(&data, &len);
+ dss->y = getmp(&data, &len);
+
+ return dss;
}
-static char *dss_fmtkey(void) {
+static void dss_freekey(void *key) {
+ struct dss_key *dss = (struct dss_key *)key;
+ freebn(dss->p);
+ freebn(dss->q);
+ freebn(dss->g);
+ freebn(dss->y);
+ sfree(dss);
+}
+
+static char *dss_fmtkey(void *key) {
+ struct dss_key *dss = (struct dss_key *)key;
char *p;
int len, i, pos, nibbles;
static const char hex[] = "0123456789abcdef";
- if (!dss_p)
+ if (!dss->p)
return NULL;
len = 8 + 4 + 1; /* 4 x "0x", punctuation, \0 */
- len += 4 * (dss_p[0] + dss_q[0] + dss_g[0] + dss_y[0]); /* digits */
- p = malloc(len);
+ len += 4 * (dss->p[0] + dss->q[0] + dss->g[0] + dss->y[0]); /* digits */
+ p = smalloc(len);
if (!p) return NULL;
pos = 0;
pos += sprintf(p+pos, "0x");
- nibbles = (3 + ssh1_bignum_bitcount(dss_p))/4; if (nibbles<1) nibbles=1;
+ nibbles = (3 + ssh1_bignum_bitcount(dss->p))/4; if (nibbles<1) nibbles=1;
for (i=nibbles; i-- ;)
- p[pos++] = hex[(bignum_byte(dss_p, i/2) >> (4*(i%2))) & 0xF];
+ p[pos++] = hex[(bignum_byte(dss->p, i/2) >> (4*(i%2))) & 0xF];
pos += sprintf(p+pos, ",0x");
- nibbles = (3 + ssh1_bignum_bitcount(dss_q))/4; if (nibbles<1) nibbles=1;
+ nibbles = (3 + ssh1_bignum_bitcount(dss->q))/4; if (nibbles<1) nibbles=1;
for (i=nibbles; i-- ;)
- p[pos++] = hex[(bignum_byte(dss_q, i/2) >> (4*(i%2))) & 0xF];
+ p[pos++] = hex[(bignum_byte(dss->q, i/2) >> (4*(i%2))) & 0xF];
pos += sprintf(p+pos, ",0x");
- nibbles = (3 + ssh1_bignum_bitcount(dss_g))/4; if (nibbles<1) nibbles=1;
+ nibbles = (3 + ssh1_bignum_bitcount(dss->g))/4; if (nibbles<1) nibbles=1;
for (i=nibbles; i-- ;)
- p[pos++] = hex[(bignum_byte(dss_g, i/2) >> (4*(i%2))) & 0xF];
+ p[pos++] = hex[(bignum_byte(dss->g, i/2) >> (4*(i%2))) & 0xF];
pos += sprintf(p+pos, ",0x");
- nibbles = (3 + ssh1_bignum_bitcount(dss_y))/4; if (nibbles<1) nibbles=1;
+ nibbles = (3 + ssh1_bignum_bitcount(dss->y))/4; if (nibbles<1) nibbles=1;
for (i=nibbles; i-- ;)
- p[pos++] = hex[(bignum_byte(dss_y, i/2) >> (4*(i%2))) & 0xF];
+ p[pos++] = hex[(bignum_byte(dss->y, i/2) >> (4*(i%2))) & 0xF];
p[pos] = '\0';
return p;
}
-static char *dss_fingerprint(void) {
+static char *dss_fingerprint(void *key) {
+ struct dss_key *dss = (struct dss_key *)key;
struct MD5Context md5c;
unsigned char digest[16], lenbuf[4];
char buffer[16*3+40];
unsigned char c = bignum_byte(bignum, i); \
MD5Update(&md5c, &c, 1); \
}
- ADD_BIGNUM(dss_p);
- ADD_BIGNUM(dss_q);
- ADD_BIGNUM(dss_g);
- ADD_BIGNUM(dss_y);
+ ADD_BIGNUM(dss->p);
+ ADD_BIGNUM(dss->q);
+ ADD_BIGNUM(dss->g);
+ ADD_BIGNUM(dss->y);
#undef ADD_BIGNUM
MD5Final(digest, &md5c);
- sprintf(buffer, "%d ", ssh1_bignum_bitcount(dss_p));
+ sprintf(buffer, "%d ", ssh1_bignum_bitcount(dss->p));
for (i = 0; i < 16; i++)
sprintf(buffer+strlen(buffer), "%s%02x", i?":":"", digest[i]);
- ret = malloc(strlen(buffer)+1);
+ ret = smalloc(strlen(buffer)+1);
if (ret)
strcpy(ret, buffer);
return ret;
}
-static int dss_verifysig(char *sig, int siglen, char *data, int datalen) {
+static int dss_verifysig(void *key, char *sig, int siglen,
+ char *data, int datalen) {
+ struct dss_key *dss = (struct dss_key *)key;
char *p;
int slen;
char hash[20];
- Bignum r, s, w, i1, i2, i3, u1, u2, sha, v;
+ Bignum r, s, w, gu1p, yu2p, gu1yu2p, u1, u2, sha, v;
int ret;
- if (!dss_p)
+ if (!dss->p)
return 0;
#ifdef DEBUG_DSS
}
sig += 4, siglen -= 4; /* skip yet another length field */
}
- diagbn("p=", dss_p);
- diagbn("q=", dss_q);
- diagbn("g=", dss_g);
- diagbn("y=", dss_y);
+ diagbn("p=", dss->p);
+ diagbn("q=", dss->q);
+ diagbn("g=", dss->g);
+ diagbn("y=", dss->y);
r = get160(&sig, &siglen);
diagbn("r=", r);
s = get160(&sig, &siglen);
/*
* Step 1. w <- s^-1 mod q.
*/
- w = modinv(s, dss_q);
+ w = modinv(s, dss->q);
diagbn("w=", w);
/*
* Step 2. u1 <- SHA(message) * w mod q.
*/
- u1 = newbn(dss_q[0]);
SHA_Simple(data, datalen, hash);
p = hash; slen = 20; sha = get160(&p, &slen);
diagbn("sha=", sha);
- modmul(sha, w, dss_q, u1);
+ u1 = modmul(sha, w, dss->q);
diagbn("u1=", u1);
/*
* Step 3. u2 <- r * w mod q.
*/
- u2 = newbn(dss_q[0]);
- modmul(r, w, dss_q, u2);
+ u2 = modmul(r, w, dss->q);
diagbn("u2=", u2);
/*
* Step 4. v <- (g^u1 * y^u2 mod p) mod q.
*/
- i1 = newbn(dss_p[0]);
- i2 = newbn(dss_p[0]);
- i3 = newbn(dss_p[0]);
- v = newbn(dss_q[0]);
- modpow(dss_g, u1, dss_p, i1);
- diagbn("gu1p=", i1);
- modpow(dss_y, u2, dss_p, i2);
- diagbn("yu2p=", i2);
- modmul(i1, i2, dss_p, i3);
- diagbn("gu1yu2p=", i3);
- modmul(i3, One, dss_q, v);
+ gu1p = modpow(dss->g, u1, dss->p);
+ diagbn("gu1p=", gu1p);
+ yu2p = modpow(dss->y, u2, dss->p);
+ diagbn("yu2p=", yu2p);
+ gu1yu2p = modmul(gu1p, yu2p, dss->p);
+ diagbn("gu1yu2p=", gu1yu2p);
+ v = modmul(gu1yu2p, One, dss->q);
diagbn("gu1yu2q=v=", v);
diagbn("r=", r);
freebn(w);
freebn(sha);
- freebn(i1);
- freebn(i2);
- freebn(i3);
+ freebn(gu1p);
+ freebn(yu2p);
+ freebn(gu1yu2p);
freebn(v);
freebn(r);
freebn(s);
return ret;
}
-struct ssh_hostkey ssh_dss = {
- dss_setkey,
+int dss_sign(void *key, char *sig, int siglen,
+ char *data, int datalen) {
+ return 0; /* do nothing */
+}
+
+struct ssh_signkey ssh_dss = {
+ dss_newkey,
+ dss_freekey,
dss_fmtkey,
dss_fingerprint,
dss_verifysig,
+ dss_sign,
"ssh-dss",
"dss"
};