Can the mount_afp command in Leopard use Keychain as it did in Tiger?

I found a workaround for this by writing a program that uses the Security framework to grab the password from the keychain, calls /sbin/mount_afp via execve, and pipes the password to the stdin of the mount_afp process. This isn't as good a solution as having mount_afp use the keychain directly, as it foregoes the checksum of the process image, and hence would not detect a malicious program substituted for mount_afp.

If this functionality were present in mount_afp for Leopard, I'd still find it useful.

Sure, let me clean it up a bit, and I'll post it.

The following C program should be compiled with the Security framework as follows:

cc -framework Security -o mountwrapper mountwrapper.c

This program works only under Leopard, and requires that you have an AFP Internet password in your keychain with the exact hostname, username, and port number you specify on the command line. It does not look for approximate or ambiguous matches.

#include <unistd.h>
#include <stdio.h>
#include <Security/SecKeychain.h>
#include <stdlib.h>
#include <string.h>

extern char **environ;

int main(int argc, char **argv)
{

UInt32 passwordLength = 0;
void *passwordData;
OSStatus keychainStatus = 0;
UInt16 serverPort = 0;
if(argc < 6)
{
fprintf(stderr, "Usage: mountwrapper <hostname> <username> <share> <port> <mountpoint>\n");
return 1;
}
sscanf(argv[4], "%hu", &serverPort);
keychainStatus = SecKeychainFindInternetPassword(0, strlen(argv[1]), argv[1], 0, 0, strlen(argv[2]), argv[2], strlen(argv[3]), argv[3], serverPort, kSecProtocolTypeAFP, kSecAuthenticationTypeDefault, &passwordLength, &passwordData, 0);
if(keychainStatus || !passwordLength)
{
fprintf(stderr, "Keychain error: %i\n", keychainStatus);
return 1;
}
int pipein = 0, pipeout = 0, forkValue;
{
int myPipes1[2], myPipes2[2];
pipe(myPipes1);
pipe(myPipes2);
forkValue = fork();
if(forkValue)
{
pipein=myPipes1[0];
pipeout=myPipes2[1];
close(myPipes2[0]);
close(myPipes1[1]);
}
else
{
pipein = myPipes2[0];
pipeout = myPipes1[1];
close(myPipes1[0]);
close(myPipes2[1]);
}
}

if(!forkValue)
{
setsid();
int URLLength;
char *URL = malloc((URLLength = strlen(argv[1]) + strlen(argv[2]) + strlen(argv[3]) + strlen(argv[4]) + 12) + 1);
char *newArgv[] = {"mount_afp", "-i", "-o", "nobrowse", URL, argv[5], 0};
char *newEnv[] = {0};
snprintf(URL, URLLength, "afp://%s@%s:%hu%s", argv[2], argv[1], serverPort, argv[3]);
while(pipein < 3)
{
int oldpipein;
pipein = dup2(oldpipein = pipein, 8);
close(oldpipein);
}
while(pipeout < 3)
{
int oldpipeout;
pipein = dup2(oldpipeout = pipeout, 9);
close(oldpipeout);
}
dup2(pipein, 0);
dup2(pipeout, 1);
dup2(pipeout, 2);
execve("/sbin/mount_afp", newArgv, environ);

}
else
{
char buffer\[1024\];
int returnParams = 0;
write(pipeout, passwordData, passwordLength);
write(pipeout, "\n", 1);
size_t bytesRead = read(pipein, buffer, 1024);
size_t bufferOffset = 0;
if(bytesRead > 10)
if(!strncmp(buffer, "Password:", 9))
bufferOffset += 11;
fwrite(buffer + bufferOffset, 1, bytesRead, stderr);
wait(&returnParams);



}
return 0;
}

oops; I put a potential buffer overrun in there; that line toward the end should be:

fwrite(buffer + bufferOffset, 1, bytesRead - bufferOffset, stderr);

not:

fwrite(buffer + bufferOffset, 1, bytesRead, stderr);