Added verification that replies come from MDP server

(including dealing with when the server is referenced via a
symlink, and verification by inode/dev is required)
This commit is contained in:
gardners 2012-03-21 02:44:36 +10:30
parent 67c4577b55
commit 2bfb6eb569

View File

@ -376,17 +376,28 @@ int overlay_mdp_dispatch(overlay_mdp_frame *mdp,int flags,int timeout_ms)
int ttl=-1; int ttl=-1;
unsigned char recvaddrbuffer[1024]; unsigned char recvaddrbuffer[1024];
struct sockaddr *recvaddr=(struct sockaddr *)recvaddrbuffer; struct sockaddr *recvaddr=(struct sockaddr *)recvaddrbuffer;
int recvaddrlen=sizeof(recvaddrbuffer); unsigned int recvaddrlen=sizeof(recvaddrbuffer);
struct sockaddr_un *recvaddr_un; struct sockaddr_un *recvaddr_un;
len = recvwithttl(mdp_client_socket,replybuffer,sizeof(replybuffer),&ttl, len = recvwithttl(mdp_client_socket,replybuffer,sizeof(replybuffer),&ttl,
recvaddr,&recvaddrlen); recvaddr,&recvaddrlen);
recvaddr_un=(struct sockaddr_un *)recvaddr; recvaddr_un=(struct sockaddr_un *)recvaddr;
if (len>0) { if (len>0) {
/* Make sure recvaddr matches who we sent it to */ /* Make sure recvaddr matches who we sent it to */
if (strcmp(mdp_socket_name,recvaddr_un->sun_path)) {
/* Okay, reply was PROBABLY not from the server, but on OSX if the path
has a symlink in it, it is resolved in the reply path, but might not
be in the request path (mdp_socket_name), thus we need to stat() and
compare inode numbers etc */
struct stat sb1,sb2;
if (stat(mdp_socket_name,&sb1)) return WHY("stat(mdp_socket_name) failed, so could not verify that reply came from MDP server");
if (stat(recvaddr_un->sun_path,&sb2)) return WHY("stat(ra->sun_path) failed, so could not verify that reply came from MDP server");
if ((sb1.st_ino!=sb2.st_ino)||(sb1.st_dev!=sb2.st_dev))
return WHY("Reply did not come from server");
}
/* If all is well, examine result and return error code provided */ /* If all is well, examine result and return error code provided */
overlay_mdp_frame *mdpreply=(overlay_mdp_frame *)&replybuffer[0]; overlay_mdp_frame *mdpreply=(overlay_mdp_frame *)&replybuffer[0];
WHY("Got a reply from server");
} }