/*	$Id: clamd_fdscan.c,v 1.2 2007/01/18 16:59:50 mbalmer Exp $	*/
 
 /*
  * Copyright (c) 2007 Marc Balmer <mbalmer@openbsd.org>
  *
  * Permission to use, copy, modify, and distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
  * copyright notice and this permission notice appear in all copies.
  *
  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
 #include <sys/types.h>
 #include <sys/socket.h>
 #include <sys/un.h>
 #include <sys/uio.h>
 #include <string.h>
 
 #include <stdio.h>
 #include <err.h>
 #include <unistd.h>
 
 #include "clamd_fdscan.h"
 
 #define CLAMD_BUFSIZ	256
 
 size_t strlcpy(char *dst, const char *src, size_t siz);
 /*
  * clamd_fdscan lets a running clamd process scan the contents of an open
  * filedescriptor by passing the filedescriptor to clamd.  The parameters
  * are as follows:
  * fd		the open filedescriptor to pass for scanning
  * soname	the path to the local clamd listening socket
  * name		virus name, if a virus is found
  * len		max len of the virus name
  *
  * The functions returns 0 if the file was scanned and contains no virus,
  * -1 if an error occurs and 1 if a virus is found.
  */
 int
 clamd_fdscan(int fd, char *soname, char *name, size_t len)
 {
 	struct sockaddr_un addr;
 	struct msghdr msg;
 	struct cmsghdr *cmsg;
 	unsigned char fdbuf[CMSG_SPACE(sizeof(int))];
 	FILE *sp;
 	char buf[CLAMD_BUFSIZ], *p, *q;
 	off_t pos;
 	int s;
 	struct iovec iov[1];
 
 	iov[0].iov_base = "";
 	iov[0].iov_len = 1;
 
 	pos = lseek(fd, 0, SEEK_CUR);
 	s = socket(AF_UNIX, SOCK_STREAM, 0);
 	memset(&addr, 0, sizeof(addr));
 	addr.sun_family = AF_UNIX;
 	strlcpy(addr.sun_path, soname, sizeof(addr.sun_path));
 	if (connect(s, (struct sockaddr *)&addr, sizeof(addr))) {
 		perror("connect");
 		return -1;
 	}
 
 	memset(&msg, 0, sizeof(msg));
 	msg.msg_control = fdbuf;
 	/* must send/receive at least one byte */
 	msg.msg_iov = iov;
 	msg.msg_iovlen = 1;
 	msg.msg_controllen = CMSG_LEN(sizeof(int));
 
 	cmsg = CMSG_FIRSTHDR(&msg);
 	cmsg->cmsg_len = CMSG_LEN(sizeof(int));
 	cmsg->cmsg_level = SOL_SOCKET;
 	cmsg->cmsg_type = SCM_RIGHTS;
 	*(int *)CMSG_DATA(cmsg) = fd;
 
 	write(s, "FILDES\n", sizeof("FILDES\n")-1);
 	if (sendmsg(s, &msg, 0) == -1) {
 		perror("sendmsg");
 		close(s);
 		return -1;
 	}
 
 	sp = fdopen(s,"r");
 	fgets(buf, sizeof(buf), sp);
 	fclose(sp);
 	close(s);
 
 	if (pos != -1)
 		lseek(fd, pos, SEEK_SET);
 	if ((p = strrchr(buf, ' ')) != NULL) {
 		++p;
 		if (!strncmp(p, "OK", 2))
 			return 0;
 		else if (!strncmp(p, "FOUND", 5)) {
 			if (name != NULL) {
 				*--p = '\0';
 				q = strrchr(buf, ' ') + 1;
 				strlcpy(name, q, len);
 			}
 			return 1;
 		} else {
 			puts(buf);
 		}
 	}
 	return -1;
 }
 
 int main(int argc, char *argv[])
 {
 	char virusname[CLAMD_BUFSIZ];
 	if(argc != 2) {
 		fprintf(stderr,"Usage: %s <clamd_socket>\n", argv[0]);
 		return 1;
 	}
 	virusname[0]=0;
 	if(clamd_fdscan(0, argv[1],virusname, sizeof(virusname)) == -1) {
 		perror("Error sending fd!");
 		return 2;
 	} else {
 		printf("FOUND: %s\n", virusname);
 	}
 	return 0;
 }