lib/libssh
1
0
Fork 0
mirror of https://git.libssh.org/projects/libssh.git synced 2025-11-30 13:01:23 +03:00
Code Activity

Use constant time comparison function for HMAC comparison

Browse Source 
Signed-off-by: Dirkjan Bussink <d.bussink@gmail.com>
Reviewed-by: Jon Simons <jon@jonsimons.org>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
This commit is contained in:
Dirkjan Bussink
2014-04-23 17:27:10 -07:00
committed by Andreas Schneider
parent 1af10fcdb3
commit 46d15b3161
1 changed files with 12 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

13
src/packet_crypt.c
View File

@@ -188,6 +188,17 @@ unsigned char *ssh_packet_encrypt(ssh_session session, void *data, uint32_t len)
return crypto->hmacbuf;
}
static int secure_memcmp(const void *s1, const void *s2, size_t n)
{
int rc = 0;
const unsigned char *p1 = s1;
const unsigned char *p2 = s2;
for (; n > 0; --n) {
rc |= *p1++ ^ *p2++;
}
return (rc != 0);
}
/**
* @internal
*
@@ -234,7 +245,7 @@ int ssh_packet_hmac_verify(ssh_session session,
ssh_print_hexa("Computed mac",hmacbuf,len);
ssh_print_hexa("seq",(unsigned char *)&seq,sizeof(uint32_t));
#endif
if (memcmp(mac, hmacbuf, len) == 0) {
if (secure_memcmp(mac, hmacbuf, len) == 0) {
return 0;
}