From 31593dd6106cfef78fc88cbe9c831a51f00a4aa6 Mon Sep 17 00:00:00 2001
From: Andrew Tridgell <tridge@samba.org>
Date: Wed, 13 May 1998 09:38:54 +0000
Subject: [PATCH 1/1] improved max connections code. Now use fcntl instead of
 flock.

also started on authentication code (I'm doing a challenge response
system initially)
---
 authenticate.c | 21 +++++++++++++
 clientserver.c | 19 +++++++++++-
 connection.c   | 81 ++------------------------------------------------
 loadparm.c     | 14 +++++++--
 util.c         | 16 ++++++----
 5 files changed, 62 insertions(+), 89 deletions(-)
 create mode 100644 authenticate.c

diff --git a/authenticate.c b/authenticate.c
new file mode 100644
index 00000000..28f777e1
--- /dev/null
+++ b/authenticate.c
@@ -0,0 +1,21 @@
+/* 
+   Copyright (C) Andrew Tridgell 1998
+   
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+   
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+   
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+/* support rsync authentication */
+#include "rsync.h"
+
diff --git a/clientserver.c b/clientserver.c
index 39e5b90d..173ca0c5 100644
--- a/clientserver.c
+++ b/clientserver.c
@@ -67,6 +67,14 @@ int start_socket_client(char *host, char *path, int argc, char *argv[])
 		if (!read_line(fd, line, sizeof(line)-1)) {
 			return -1;
 		}
+
+#if 0
+		if (strncmp(line,"@RSYNCD: AUTHREQD ",18) == 0) {
+			auth_client(fd, line+18);
+			continue;
+		}
+#endif
+
 		if (strcmp(line,"@RSYNCD: OK") == 0) break;
 		rprintf(FINFO,"%s\n", line);
 	}
@@ -101,6 +109,7 @@ static int rsync_module(int fd, int i)
 	char *p;
 	char *addr = client_addr(fd);
 	char *host = client_name(fd);
+	char *auth;
 
 	if (!allow_access(addr, host, lp_hosts_allow(i), lp_hosts_deny(i))) {
 		rprintf(FERROR,"rsync denied on module %s from %s (%s)\n",
@@ -108,6 +117,14 @@ static int rsync_module(int fd, int i)
 		return -1;
 	}
 
+#if 0
+	if (!auth_server(fd, "@RSYNCD: AUTHREQD ")) {
+		rprintf(FERROR,"auth failed on module %s from %s (%s)\n",
+			lp_name(i), client_name(fd), client_addr(fd));
+		return -1;		
+	}
+#endif
+
 	if (!claim_connection(lp_lock_file(), lp_max_connections())) {
 		rprintf(FERROR,"ERROR: max connections reached\n");
 		return -1;
@@ -115,7 +132,7 @@ static int rsync_module(int fd, int i)
 
 	rprintf(FINFO,"rsync on module %s from %s (%s)\n",
 		lp_name(i), host, addr);
-
+	
 	module_id = i;
 
 	if (lp_read_only(i))
diff --git a/connection.c b/connection.c
index fc7c6667..1025c8fc 100644
--- a/connection.c
+++ b/connection.c
@@ -19,59 +19,6 @@
 /* support the max connections option */
 #include "rsync.h"
 
-int yield_connection(char *fname, int max_connections)
-{
-	int fd, i;
-	pid_t mypid=getpid(), pid=0;
-
-	if (max_connections <= 0)
-		return 1;
-
-	fd = open(fname,O_RDWR);
-	if (fd == -1) {
-		rprintf(FERROR,"Couldn't open lock file %s (%s)\n",fname,strerror(errno));
-		return 0;
-	}
-
-	if (!lock_file(fd)) {
-		rprintf(FERROR,"failed to lock %s\n", fname);
-		close(fd);
-		return 0;
-	}
-
-	/* find the right spot */
-	for (i=0;i<max_connections;i++) {
-		if (read(fd, &pid, sizeof(pid)) != sizeof(pid)) {
-			unlock_file(fd);
-			close(fd);
-			return 0;
-		}
-		if (pid == mypid) break;
-	}
-
-	if (i == max_connections) {
-		rprintf(FERROR,"Entry not found in lock file %s\n",fname);
-		unlock_file(fd);
-		close(fd);
-		return 0;
-	}
-
-	pid = 0;
-  
-	/* remove our mark */
-	if (lseek(fd,i*sizeof(pid),SEEK_SET) != i*sizeof(pid) ||
-	    write(fd, &pid,sizeof(pid)) != sizeof(pid)) {
-		rprintf(FERROR,"Couldn't update lock file %s (%s)\n",fname,strerror(errno));
-		unlock_file(fd);
-		close(fd);
-		return 0;
-	}
-
-	unlock_file(fd);
-	close(fd);
-	return 1;
-}
-
 
 /****************************************************************************
 simple routine to do connection counting
@@ -79,7 +26,6 @@ simple routine to do connection counting
 int claim_connection(char *fname,int max_connections)
 {
 	int fd, i;
-	pid_t pid;
 
 	if (max_connections <= 0)
 		return 1;
@@ -90,34 +36,11 @@ int claim_connection(char *fname,int max_connections)
 		return 0;
 	}
 
-	if (!lock_file(fd)) {
-		rprintf(FERROR,"failed to lock %s\n", fname);
-		close(fd);
-		return 0;
-	}
-
 	/* find a free spot */
 	for (i=0;i<max_connections;i++) {
-		if (read(fd,&pid,sizeof(pid)) != sizeof(pid)) break;
-		if (pid == 0 || !process_exists(pid)) break;
+		if (lock_range(fd, i*4, 4)) return 1;
 	}		
 
-	if (i == max_connections) {
-		unlock_file(fd);
-		close(fd);
-		return 0;
-	}
-
-	pid = getpid();
-
-	if (lseek(fd,i*sizeof(pid),SEEK_SET) != i*sizeof(pid) ||
-	    write(fd, &pid,sizeof(pid)) != sizeof(pid)) {
-		unlock_file(fd);
-		close(fd);
-		return 0;
-	}
-
-	unlock_file(fd);
 	close(fd);
-	return 1;
+	return 0;
 }
diff --git a/loadparm.c b/loadparm.c
index da2e2270..ceb06a5f 100644
--- a/loadparm.c
+++ b/loadparm.c
@@ -57,13 +57,13 @@ typedef char pstring[1024];
 /* the following are used by loadparm for option lists */
 typedef enum
 {
-  P_BOOL,P_BOOLREV,P_CHAR,P_INTEGER,P_OCTAL,
-  P_STRING,P_GSTRING,P_ENUM,P_SEP
+	P_BOOL,P_BOOLREV,P_CHAR,P_INTEGER,P_OCTAL,
+	P_STRING,P_GSTRING,P_ENUM,P_SEP
 } parm_type;
 
 typedef enum
 {
-  P_LOCAL,P_GLOBAL,P_SEPARATOR,P_NONE
+	P_LOCAL,P_GLOBAL,P_SEPARATOR,P_NONE
 } parm_class;
 
 struct enum_list {
@@ -121,6 +121,8 @@ typedef struct
 	char *gid;
 	char *hosts_allow;
 	char *hosts_deny;
+	char *auth_users;
+	char *secrets_file;
 } service;
 
 
@@ -136,6 +138,8 @@ static service sDefault =
 	"nobody",/* gid */
 	NULL,    /* hosts allow */
 	NULL,    /* hosts deny */
+	NULL,    /* auth users */
+	NULL,    /* secrets file */
 };
 
 
@@ -165,6 +169,8 @@ static struct parm_struct parm_table[] =
   {"gid",              P_STRING,  P_LOCAL,  &sDefault.gid,         NULL,   0},
   {"hosts allow",      P_STRING,  P_LOCAL,  &sDefault.hosts_allow, NULL,   0},
   {"hosts deny",       P_STRING,  P_LOCAL,  &sDefault.hosts_deny,  NULL,   0},
+  {"auth users",       P_STRING,  P_LOCAL,  &sDefault.auth_users,  NULL,   0},
+  {"secrets file",     P_STRING,  P_LOCAL,  &sDefault.secrets_file,NULL,   0},
   {NULL,               P_BOOL,    P_NONE,   NULL,                  NULL,   0}
 };
 
@@ -225,6 +231,8 @@ FN_LOCAL_STRING(lp_uid, uid)
 FN_LOCAL_STRING(lp_gid, gid)
 FN_LOCAL_STRING(lp_hosts_allow, hosts_allow)
 FN_LOCAL_STRING(lp_hosts_deny, hosts_deny)
+FN_LOCAL_STRING(lp_auth_users, auth_users)
+FN_LOCAL_STRING(lp_secrets_file, secrets_file)
 
 /* local prototypes */
 static int    strwicmp( char *psz1, char *psz2 );
diff --git a/util.c b/util.c
index bcbd8c1b..7d15a8a6 100644
--- a/util.c
+++ b/util.c
@@ -491,12 +491,16 @@ int process_exists(int pid)
 	return(kill(pid,0) == 0 || errno != ESRCH);
 }
 
-int lock_file(int fd)
+/* lock a byte range in a open file */
+int lock_range(int fd, int offset, int len)
 {
-	return flock(fd, LOCK_EX) == 0;
-}
+	struct flock lock;
 
-int unlock_file(int fd)
-{
-	return flock(fd, LOCK_UN) == 0;
+	lock.l_type = F_WRLCK;
+	lock.l_whence = SEEK_SET;
+	lock.l_start = offset;
+	lock.l_len = len;
+	lock.l_pid = 0;
+	
+	return fcntl(fd,F_SETLK,&lock) == 0;
 }
-- 
2.34.1