* HMAC wrapper on it.
*/
-static struct MD5Context md5_cs_mac_s1, md5_cs_mac_s2;
-static struct MD5Context md5_sc_mac_s1, md5_sc_mac_s2;
+static void *md5_make_context(void)
+{
+ return smalloc(2*sizeof(struct MD5Context));
+}
+
+static void md5_free_context(void *handle)
+{
+ sfree(handle);
+}
-static void md5_key(struct MD5Context *s1, struct MD5Context *s2,
- unsigned char *key, int len)
+static void md5_key_internal(void *handle, unsigned char *key, int len)
{
+ struct MD5Context *keys = (struct MD5Context *)handle;
unsigned char foo[64];
int i;
memset(foo, 0x36, 64);
for (i = 0; i < len && i < 64; i++)
foo[i] ^= key[i];
- MD5Init(s1);
- MD5Update(s1, foo, 64);
+ MD5Init(&keys[0]);
+ MD5Update(&keys[0], foo, 64);
memset(foo, 0x5C, 64);
for (i = 0; i < len && i < 64; i++)
foo[i] ^= key[i];
- MD5Init(s2);
- MD5Update(s2, foo, 64);
+ MD5Init(&keys[0]);
+ MD5Update(&keys[0], foo, 64);
memset(foo, 0, 64); /* burn the evidence */
}
-static void md5_cskey(unsigned char *key)
-{
- md5_key(&md5_cs_mac_s1, &md5_cs_mac_s2, key, 16);
-}
-
-static void md5_sckey(unsigned char *key)
+static void md5_key(void *handle, unsigned char *key)
{
- md5_key(&md5_sc_mac_s1, &md5_sc_mac_s2, key, 16);
+ md5_key_internal(handle, key, 16);
}
-static void md5_do_hmac(struct MD5Context *s1, struct MD5Context *s2,
- unsigned char *blk, int len, unsigned long seq,
- unsigned char *hmac)
+static void md5_do_hmac(void *handle, unsigned char *blk, int len,
+ unsigned long seq, unsigned char *hmac)
{
+ struct MD5Context *keys = (struct MD5Context *)handle;
struct MD5Context s;
unsigned char intermediate[16];
intermediate[2] = (unsigned char) ((seq >> 8) & 0xFF);
intermediate[3] = (unsigned char) ((seq) & 0xFF);
- s = *s1; /* structure copy */
+ s = keys[0]; /* structure copy */
MD5Update(&s, intermediate, 4);
MD5Update(&s, blk, len);
MD5Final(intermediate, &s);
- s = *s2; /* structure copy */
+ s = keys[1]; /* structure copy */
MD5Update(&s, intermediate, 16);
MD5Final(hmac, &s);
}
-static void md5_generate(unsigned char *blk, int len, unsigned long seq)
+static void md5_generate(void *handle, unsigned char *blk, int len,
+ unsigned long seq)
{
- md5_do_hmac(&md5_cs_mac_s1, &md5_cs_mac_s2, blk, len, seq, blk + len);
+ md5_do_hmac(handle, blk, len, seq, blk + len);
}
-static int md5_verify(unsigned char *blk, int len, unsigned long seq)
+static int md5_verify(void *handle, unsigned char *blk, int len,
+ unsigned long seq)
{
unsigned char correct[16];
- md5_do_hmac(&md5_sc_mac_s1, &md5_sc_mac_s2, blk, len, seq, correct);
+ md5_do_hmac(handle, blk, len, seq, correct);
return !memcmp(correct, blk + len, 16);
}
const struct ssh_mac ssh_md5 = {
- md5_cskey, md5_sckey,
- md5_generate,
- md5_verify,
+ md5_make_context, md5_free_context, md5_key,
+ md5_generate, md5_verify,
"hmac-md5",
16
};