Source Code 1992 March/Source_Code_CD-ROM_Walnut_Creek_March_1992.iso/usenet/altsrcs/2/2687

Internet Message Format | 1991-02-08 | 5.3 KB

From: [e-mail] (Dan Bernstein)
Newsgroups: alt.sources
Subject: Unofficial patches to talk for RFC 931 support
Message-ID: <19568:Feb709:49:[e-mail]>
Date: 7 Feb 91 09:49:52 GMT

These are unofficial patches to BSD 4.3 talk (the version on
gatekeeper.dec.com). They change the ``Connection established'' message
to ``Connection established to user@host, authenticating...'', which
rapidly changes to ``Connection established to user@host (user@host)''.
The first user@host is what you typed; the second one uses RFC 931 to
authenticate the connection, and will detect spoofs in what is otherwise
a quite insecure system. If the remote system doesn't support RFC 931,
talk will report ``unknown@host'' for the second ID.

These patches require the authuser library, part of the authd package
posted here recently.

---Dan

*** Makefile.old    Wed Sep 28 01:28:11 1988
--- Makefile    Thu Feb  7 04:14:31 1991
***************
*** 27,33 ****
  all: talk

  talk: ${OBJS} ${LIBC}
!     ${CC} -o $@ ${CFLAGS} ${OBJS} -lcurses -ltermlib

  clean:
      rm -f ${OBJS} core talk
--- 27,33 ----
  all: talk

  talk: ${OBJS} ${LIBC}
!     ${CC} -o $@ ${CFLAGS} ${OBJS} -lcurses -ltermlib -lauthuser

  clean:
      rm -f ${OBJS} core talk
*** io.c.old    Thu Feb  7 03:46:13 1991
--- io.c    Thu Feb  7 04:34:16 1991
***************
*** 29,34 ****
--- 29,38 ----
  #include <stdio.h>
  #include <errno.h>
  #include <sys/time.h>
+ #include <sys/types.h>
+ #include <netinet/in.h>
+ #include <arpa/inet.h>
+ extern char *auth_tcpuser();

  #define A_LONG_TIME 10000000
  #define STDIN_MASK (1<<fileno(stdin))    /* the bit mask for standard
***************
*** 35,40 ****
--- 39,47 ----
                         input */
  extern int errno;

+ char *remname;
+ char *remhost;
+
  /*
   * The routine to do the actual talking
   */
***************
*** 44,51 ****
      int read_set, nb;
      char buf[BUFSIZ];
      struct timeval wait;

!     message("Connection established\007\007\007");
      current_line = 0;
      sockt_mask = (1<<sockt);

--- 51,85 ----
      int read_set, nb;
      char buf[BUFSIZ];
      struct timeval wait;
+   unsigned long in;
+   struct in_addr sa;
+   unsigned short local;
+   unsigned short remote;
+   char *user;
+   char *host;
+   char mess[500];

!   sprintf(mess
!       ,"Connection established\007\007\007 to %.50s%s%.150s, authenticating..."
!       ,remname,remhost ? "@" : "",remhost ? remhost : "");
!   message(mess);
!
!   if (auth_fd(sockt,&in,&local,&remote) == -1)
!     host = user = 0; /* XXX: so f'ing impossible it's not even funny */
!   else
!    {
!     user = auth_tcpuser(in,local,remote);
!     sa.s_addr = in;
!     host = inet_ntoa(sa);
!    }
!
!   if (!user) user = "unknown";
!   if (!host) host = "unknown";
!
!   sprintf(mess,"Connection established to %.50s%s%.150s (%.50s@%.50s)"
!       ,remname,remhost ? "@" : "",remhost ? remhost : "",user,host);
!
!   message(mess);
      current_line = 0;
      sockt_mask = (1<<sockt);

*** get_addrs.c.old    Tue Oct 11 16:42:28 1988
--- get_addrs.c    Thu Feb  7 04:49:29 1991
***************
*** 32,39 ****
      /* look up the address of the local host */
      hp = gethostbyname(my_machine_name);
      if (hp == NULL) {
!         fprintf(stderr, "talk: %s: ", my_machine_name);
!         herror((char *)NULL);
          exit(-1);
      }
      bcopy(hp->h_addr, (char *)&my_machine_addr, hp->h_length);
--- 32,38 ----
      /* look up the address of the local host */
      hp = gethostbyname(my_machine_name);
      if (hp == NULL) {
!         fprintf(stderr, "talk: %s: unknown host\n", my_machine_name);
          exit(-1);
      }
      bcopy(hp->h_addr, (char *)&my_machine_addr, hp->h_length);
***************
*** 44,51 ****
      if (strcmp(his_machine_name, my_machine_name)) {
          hp = gethostbyname(his_machine_name);
          if (hp == NULL) {
!             fprintf(stderr, "talk: %s: ", his_machine_name);
!             herror((char *)NULL);
              exit(-1);
          }
          bcopy(hp->h_addr, (char *) &his_machine_addr, hp->h_length);
--- 43,49 ----
      if (strcmp(his_machine_name, my_machine_name)) {
          hp = gethostbyname(his_machine_name);
          if (hp == NULL) {
!             fprintf(stderr, "talk: %s: unknown host\n", his_machine_name);
              exit(-1);
          }
          bcopy(hp->h_addr, (char *) &his_machine_addr, hp->h_length);
*** get_names.c.old    Wed Jun 29 23:22:35 1988
--- get_names.c    Thu Feb  7 04:32:01 1991
***************
*** 29,34 ****
--- 29,37 ----
  char    *rindex();
  extern    CTL_MSG msg;

+ extern char *remname; /* to print after Connection established */
+ extern char *remhost;
+
  /*
   * Determine the local and remote user, tty, and machines
   */
***************
*** 66,82 ****
          ;
      if (*cp == '\0') {
          /* this is a local to local talk */
!         his_name = argv[1];
          his_machine_name = my_machine_name;
      } else {
          if (*cp++ == '@') {
              /* user@host */
!             his_name = argv[1];
!             his_machine_name = cp;
          } else {
              /* host.user or host!user or host:user */
!             his_name = cp;
!             his_machine_name = argv[1];
          }
          *--cp = '\0';
      }
--- 69,86 ----
          ;
      if (*cp == '\0') {
          /* this is a local to local talk */
!         remname = his_name = argv[1];
          his_machine_name = my_machine_name;
+         remhost = 0;
      } else {
          if (*cp++ == '@') {
              /* user@host */
!             remname = his_name = argv[1];
!             remhost = his_machine_name = cp;
          } else {
              /* host.user or host!user or host:user */
!             remname = his_name = cp;
!             remhost = his_machine_name = argv[1];
          }
          *--cp = '\0';
      }