Adding Authinfo Support

diff -U 3 --new-file sn-0.3.5/CHANGES sn-0.3.6/CHANGES
--- sn-0.3.5/CHANGES	Sat Jul  6 08:38:51 2002
+++ sn-0.3.6/CHANGES	Mon Dec  9 20:51:37 2002
@@ -1,5 +1,26 @@
 --
-0.3.5 Sat Jul  6 18:37:50 EEST 2002
+0.3.6 Sun Dec 8 21:17:30 PDT 2002
+Added AUTHINFO functionality.  I mean, jeez...
+New configuration files:
+SNROOT/user.allow
+	file with "user:password" pairs, one per line
+	Note, the "user:password" line has a MAX of 200 characters,
+		'cause I'm too lazy to use dynamic memory.  Administrators
+		beware.
+	Note, this file has to be chown news.news and chmod o-rw or snntpd 
+		will not use it and post a warning log.
+
+SNROOT/.auth
+	presence activates authentication
+
+The RFC didn't say to drop the connection on failed authentication,
+but my emacs gnus seems to depend on that and I noticed another news
+server doing it so...
+
+entry by Starling ([email protected])
+
+--
+0.3.5 Sat Jul 6 18:37:50 EEST 2002
 Added an FAQ, containg the solution to the infamous POST problem.
 NEWGROUPS and NEWNEWS now works properly during DST. (Was offset one hour.)
 Made "sncat -i foo" work for users with read-only access to the spool.
@@ -34,7 +55,7 @@
 snexpire bug related to =junk.
 writefifo has been failing for a few revs now!  Fixed.
 --
-0.3.2 Fri Mar  3 22:33:02 SGT 2000
+0.3.2 Fri Mar 3 22:33:02 SGT 2000
 Changed ctime to mtime, when checking .created.
 Date conversion error, e.g. for NEWGROUPS and NEWNEWS.
 Doc error, command line example using tcpserver.
@@ -99,14 +120,14 @@
 snget (and others) takes -P, passes to snfetch.
 0-length article bodies now legal in snntpd and snscan.
 --
-0.2.3 Mon Dec  7 12:44:03 SGT 1998
+0.2.3 Mon Dec 7 12:44:03 SGT 1998
 Option -m for snget to limit initial articles.
 snpost locking now performed.
 snmail EOL conversion error; rewrite.
 snntpd LIST command output format error.
 snfetch rnews format error.
 --
-0.2.2 Thu Oct  8 11:02:54 SGT 1998
+0.2.2 Thu Oct 8 11:02:54 SGT 1998
 -r option in snstore, snfetch, sncat.
 Rewrote snget as binary instead of script.
 Merged dh_dump() into sndumpdb.c, it didn't belong in dhash.c.
@@ -125,7 +146,7 @@
 Better snpost reporting.
 Off-by-one in art.c, resulting in random crashes.
 --
-0.2.1 Wed Aug  5 18:29:37 SGT 1998
+0.2.1 Wed Aug 5 18:29:37 SGT 1998
 Missing realloc in subscribed.c, reorg in newsgroup.c.
 --
 0.2.0 Sat Jul 11 13:34:03 SGT 1998
diff -U 3 --new-file sn-0.3.5/Makefile sn-0.3.6/Makefile
--- sn-0.3.5/Makefile	Wed Jun 12 03:16:33 2002
+++ sn-0.3.6/Makefile	Sun Dec  8 23:14:06 2002
@@ -10,14 +10,14 @@
 ## No: Leave ZLIB undefined.
 #ZLIB =
 ## Where the news spool will be, e.g.: SNROOT=/var/spool/news
-SNROOT =/home/patrik/spool/news
+SNROOT =/var/spool/news
 ## Where to install the executables, e.g.: BINDIR=/usr/local/sbin
-BINDIR =/home/patrik/sn/bin
+BINDIR =/usr/local/news/bin
 ## Where to install the man pages, e.g.: MANDIR=/usr/local/man
-MANDIR =/home/patrik/sn/man
+MANDIR =/usr/local/news/man
 ## Where to send mail for the admin if neither the NEWSMASTER nor
 ## the LOGNAME environment variable is set
-DEFAULT_ADMIN_EMAIL =newsmaster
+DEFAULT_ADMIN_EMAIL =news
 
 #
 # OS-specific settings. Uncomment only one section below.
@@ -47,7 +47,7 @@
 #
 
 VERSION =0.3.5
-AOBJS =art.o cache.o group.o times.o dh_find.o dhash.o \
+AOBJS =art.o auth.o cache.o group.o times.o dh_find.o dhash.o \
  allocate.o newsgroup.o hostname.o \
  store.o parameters.o args.o body.o unfold.o path.o \
  addr.o valid.o key.o field.o
@@ -166,6 +166,7 @@
 ## DO NOT REMOVE ##
 
 art.o: art.c config.h art.h artfile.h cache.h
+auth.o: auth.c auth.h
 cache.o: cache.c cache.h
 group.o: group.c config.h cache.h group.h artfile.h
 times.o: times.c config.h times.h cache.h
diff -U 3 --new-file sn-0.3.5/auth.c sn-0.3.6/auth.c
--- sn-0.3.5/auth.c	Wed Dec 31 16:00:00 1969
+++ sn-0.3.6/auth.c	Mon Dec  9 20:43:48 2002
@@ -0,0 +1,111 @@
+#include "auth.h"
+#include <stdio.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <errno.h>
+
+extern void log (char *fmt, ...);
+
+struct authinfo auth;
+int auth_required = 0;
+
+#define BUFSIZE 200
+
+static char complete[BUFSIZE];
+static char buffer[BUFSIZE];
+
+int checkperms(int fd)
+{
+	struct stat statbuf;
+
+	if(fstat(fd, &statbuf))
+	{
+		log("Stat error! %s\n", strerror(errno));
+		return 0;
+	}
+
+	if(statbuf.st_mode & ( S_IWOTH | S_IROTH | S_IXOTH) ||
+	   statbuf.st_uid != getuid() ||
+	   statbuf.st_gid != getgid())
+	{
+		log("user.allow needs to be chown news.news or chmod 660.");
+		return 0;
+	}
+
+	return 1;
+}	
+
+int find_user(char* data)
+{
+	FILE* db = fopen("user.allow", "r");
+	int len = 0;
+
+	if(!db) goto FAIL;
+
+	if(!checkperms(fileno(db))) goto FAIL;
+
+	while(fgets(buffer, BUFSIZE, db))
+	{
+		if((len = (int) (strchr(buffer, ':') - buffer)))
+		{
+			strncpy(complete, buffer, len);
+			if(!strncmp(complete, data, strlen(data)))
+			{
+				fclose(db);
+				return 1;
+			}
+		}
+	}
+
+  FAIL:
+
+	bzero(complete, BUFSIZE);
+
+	fclose(db);
+	return 0;
+}
+
+int find_pass(char* data)
+{
+	FILE* db = fopen("user.allow", "r");
+
+	if(!db) goto FAIL;
+	if(!checkperms(fileno(db))) goto FAIL;
+
+	strcat(complete, ":");
+	
+	if(strlen(data) + strlen(complete) > BUFSIZE) goto FAIL;
+	
+	strcat(complete, data);
+
+	while(fgets(buffer, BUFSIZE, db))
+	{
+		char* p = strchr(buffer, '\n');
+		if(p) *p = '\0';
+		
+		if(!strcmp(buffer, complete))
+		{
+			fclose(db);
+			return 1;
+		}
+	}
+
+  FAIL:
+
+	bzero(complete, BUFSIZE);
+
+	fclose(db);
+	return 0;
+}
+
+void check_user(char* data)
+{
+	auth.user = find_user(data);
+}
+
+void check_pass(char* data)
+{
+	auth.pass = auth.user = find_pass(data);
+}
diff -U 3 --new-file sn-0.3.5/auth.h sn-0.3.6/auth.h
--- sn-0.3.5/auth.h	Wed Dec 31 16:00:00 1969
+++ sn-0.3.6/auth.h	Sun Dec  8 23:14:06 2002
@@ -0,0 +1,12 @@
+/* Interface for authorization. */
+
+struct authinfo {
+	int user;
+	int pass;
+};
+
+extern struct authinfo auth;
+extern int auth_required;
+
+void check_user(char* data);
+void check_pass(char* data);
diff -U 3 --new-file sn-0.3.5/commands.c sn-0.3.6/commands.c
--- sn-0.3.5/commands.c	Tue May 28 14:31:44 2002
+++ sn-0.3.6/commands.c	Sun Dec  8 23:26:35 2002
@@ -27,6 +27,7 @@
 #include "body.h"
 #include "snntpd.h"
 #include "key.h"
+#include "auth.h"
 #include <b.h>
 #include <tokensep.h>
 #include <wildmat.h>
@@ -37,18 +38,76 @@
 
 #define putdot() args_write(1, ".\r\n")
 
-void do_ihave (void) { args_write(1, "435 I'm happy for you\r\n"); }
+void do_ihave (void) { args_write(1, "435 I'm happy for you.  Try post.\r\n"); }
 void do_sendme (void) { args_write(1, "500 No thanks\r\n"); }
-void do_slave (void) { args_write(1, "202 Whatever\r\n"); }
+void do_slave (void) { args_write(1, "202 Not since the civil war, yank.\r\n"); }
 void do_help (void) { args_write(1, "100 Help yourself\r\n.\r\n"); }
 
 void do_mode (void)
 {
-   if (posting_ok)
-      args_write(1, "200 Hi, you can post (sn version " VERSION ")\r\n");
-   else
-      args_write(1, "201 Hi, you can't post (sn version " VERSION ")\r\n");
+	if (posting_ok)
+		args_write(1, "200 Hi, you can post (sn version " VERSION ")\r\n");
+	else
+		args_write(1, "201 Hi, you can't post (sn version " VERSION ")\r\n");
 }
+
+/* Authorization mode.  */
+
+extern void do_quit(void);
+
+void do_authinfo(void)
+{
+	char flag;
+	char* data;
+
+	if(!auth_required)
+	{
+		args_write(1, "102 No authorization required.\r\n");
+		return;
+	}
+
+	if(strcasecmp(args[1],"user") && strcasecmp(args[1], "pass")) {
+		args_write(1, "501 Usage authinfo user <user> then authinfo pass <pass>\r\n");
+		return;
+	}
+
+	flag = args[1][0];
+	data = args[2];
+
+	switch(flag)
+	{
+		case 'u':
+		case 'U':
+			check_user(data);
+			args_write(1, "381 PASS required for %s\r\n", data);
+			break;
+		case 'p':
+		case 'P':
+			if(!auth.user)
+			{
+				args_write(1, "482 USER required\r\n");
+				break;
+			} else {
+				check_pass(data);
+				if(!auth.pass)
+				{
+					args_write(1, "502 Authentication failed\r\n");
+					do_quit();
+				}
+			}
+			break;
+		default:
+			args_write(1, "502 %s doesn't start with '%c'?\r\n", args[1], flag);
+			break;
+	};
+
+	if(auth.user && auth.pass)
+	{
+		posting_ok = 1;
+		args_write(1, "281 I know you!  You can post\r\n");
+	}
+}
+	
 
 /* Several ways to specify an article.  The group may be the current
    one, or it may be a different one */
Common subdirectories: sn-0.3.5/lib and sn-0.3.6/lib
diff -U 3 --new-file sn-0.3.5/parameters.c sn-0.3.6/parameters.c
--- sn-0.3.5/parameters.c	Thu May 23 17:37:11 2002
+++ sn-0.3.6/parameters.c	Sun Dec  8 23:14:06 2002
@@ -27,7 +27,7 @@
       snroot = SNROOT;
 
    if (-1 == stat(snroot, &st))
-      fail(2, "Can't find \"%s\":%m");
+      fail(2, "Can't find \"%s\":%m", snroot);
    if (!S_ISDIR(st.st_mode))
       fail(2, "%s is not a directory");
    snuid = st.st_uid;
diff -U 3 --new-file sn-0.3.5/post.c sn-0.3.6/post.c
--- sn-0.3.5/post.c	Sat Oct  6 09:39:48 2001
+++ sn-0.3.6/post.c	Sun Dec  8 23:14:06 2002
@@ -98,7 +98,10 @@
 
    if (!posting_ok)
    {
-      args_write(1, "440 Posting not allowed\r\n");
+      if(!auth_required)
+		  args_write(1, "440 Posting not allowed\r\n");
+	  else
+		  args_write(1, "480 Authorization required\r\n");
       return;
    }
 
diff -U 3 --new-file sn-0.3.5/snntpd.8.in sn-0.3.6/snntpd.8.in
--- sn-0.3.5/snntpd.8.in	Mon Jul 26 02:55:49 1999
+++ sn-0.3.6/snntpd.8.in	Mon Dec  9 20:45:40 2002
@@ -48,7 +48,7 @@
 .SH POSTING AND POSTING PERMISSIONS
 Posts are usually handled externally by the
 .RB !!BINDIR!!/ POST
-script, 
+script,
 which is responsible for fine-grain posting control; handling of
 control messages; and the ultimate distribution of the posted
 article.
@@ -73,6 +73,19 @@
 .RB $ POSTING_OK
 is not currently used, but is reserved.
 
+
+.TP
+.B AUTHINFO
+If
+.RB !!SNROOT!!/ .auth
+exists, authinfo support is enabled.
+
+.RB !!SNROOT!!/ user.access
+should have a list of newline delineated user:pass pairs for
+which user is authorized by which password.  These do not
+correspond to login users.  user.access must be owned by
+news.news and not world read or writeable.
+
 .SH FILES
 .TP
 .RB !!SNROOT!!/ .fifo
@@ -94,6 +107,12 @@
 
 .TP
 .RB !!SNROOT!!/ .nopost
+See
+.B POSTING PERMISSIONS
+above.
+
+.TP
+.RB !!SNROOT!!/ .auth
 See
 .B POSTING PERMISSIONS
 above.
diff -U 3 --new-file sn-0.3.5/snntpd.c sn-0.3.6/snntpd.c
--- sn-0.3.5/snntpd.c	Mon May 27 13:17:35 2002
+++ sn-0.3.6/snntpd.c	Sun Dec  8 23:14:06 2002
@@ -55,6 +55,7 @@
 extern int currentserial;
 
 extern void do_article (void);
+extern void do_authinfo(void);
 extern void do_body (void);
 extern void do_group (void);
 extern void do_head (void);
@@ -91,6 +92,7 @@
 
 static struct cmd cmds[] = {
    DEF(article, 1, 0, 0, 0)
+   DEF(authinfo, 3, 0, 0, 0)
    DEF(body, 1, 0, 0, 0)
    DEF(group, 2, 0, 0, 1)
    DEF(head, 1, 0, 0, 0)
@@ -199,6 +201,15 @@
       posting_ok = 1;
    else
       posting_ok = 0;
+
+   if (0 == stat(".auth", &st))
+   {
+	   auth_required = 1;
+	   posting_ok = 0;
+   }
+   else
+	   auth_required = 0;
+   
    openfifo();
    checkservice = 0;
 }
diff -U 3 --new-file sn-0.3.5/snntpd.h sn-0.3.6/snntpd.h
--- sn-0.3.5/snntpd.h	Sat Oct  6 10:27:33 2001
+++ sn-0.3.6/snntpd.h	Sun Dec  8 23:14:06 2002
@@ -9,6 +9,7 @@
 #define SNNTPD_H
 
 extern int posting_ok;
+extern int auth_required;
 extern char *client_ip;
 extern char *me;
 extern struct readln input;
diff -U 3 --new-file sn-0.3.5/user.allow.EXAMPLE sn-0.3.6/user.allow.EXAMPLE
--- sn-0.3.5/user.allow.EXAMPLE	Wed Dec 31 16:00:00 1969
+++ sn-0.3.6/user.allow.EXAMPLE	Sun Dec  8 23:45:52 2002
@@ -0,0 +1,6 @@
+ima_user:mypassword
+Foobar:eatshorts
+Hmm:dmm
+Dorothy:toto
+legolas:gandalf
+ozy:millie
\ No newline at end of file