--tftp-lowercase option.

CHANGELOG

@@ -93,6 +93,9 @@ version 2.61
 	    Give correct from-cache answers to explict CNAME queries.
 	    Thanks to Rob Zwissler for spotting this.
 	    
+	    Add --dhcp-lowercase option. Thanks to Oliver Rath for the
+	    patch. 
+	    
 
 version 2.60
             Fix compilation problem in Mac OS X Lion. Thanks to Olaf

man/dnsmasq.8

@@ -1385,6 +1385,12 @@ are accessible. It is not recommended to run dnsmasq as root with TFTP
 enabled, and certainly not without specifying --tftp-root. Doing so
 can expose any world-readable file on the server to any host on the net. 
 .TP
+.B --tftp-lowercase
+Convert filenames in TFTP requests to all lowercase. This is useful
+for requests from Windows machines, which have case-insensitive
+filesystems and tend to play fast-and-loose with case in filenames.
+Note that dnsmasq's tftp server always converts "\\" to "/" in filenames.
+.TP
 .B --tftp-max=<connections>
 Set the maximum number of concurrent TFTP connections allowed. This
 defaults to 50. When serving a large number of TFTP connections,

src/dnsmasq.h

@@ -217,7 +217,8 @@ struct event_desc {
 #define OPT_CONNTRACK      35
 #define OPT_FQDN_UPDATE    36
 #define OPT_RA             37
-#define OPT_LAST           38
+#define OPT_TFTP_LC        38
+#define OPT_LAST           39
 
 /* extra flags for my_syslog, we use a couple of facilities since they are known 
    not to occupy the same bits as priorities, no matter how syslog.h is set up. */

src/network.c

@@ -266,10 +266,13 @@ static int iface_allowed(struct irec **irecp, int if_index,
       iface->dad = dad;
       iface->done = 0;
       if ((iface->name = whine_malloc(strlen(ifr.ifr_name)+1)))
-	strcpy(iface->name, ifr.ifr_name);
-      iface->next = *irecp;
-      *irecp = iface;
-      return 1;
+	{
+	  strcpy(iface->name, ifr.ifr_name);
+	  iface->next = *irecp;
+	  *irecp = iface;
+	  return 1;
+	}
+      free(iface);
     }
   
   errno = ENOMEM; 

src/option.c

@@ -117,6 +117,7 @@ struct myoption {
 #define LOPT_RA        306
 #define LOPT_DUID      307
 #define LOPT_HOST_REC  308
+#define LOPT_TFTP_LC   309
 
 #ifdef HAVE_GETOPT_LONG
 static const struct option opts[] =  
@@ -196,6 +197,7 @@ static const struct myoption opts[] =
     { "tftp-unique-root", 0, 0, LOPT_APREF },
     { "tftp-root", 1, 0, LOPT_PREFIX },
     { "tftp-max", 1, 0, LOPT_TFTP_MAX },
+    { "tftp-lowercase", 0, 0, LOPT_TFTP_LC },
     { "ptr-record", 1, 0, LOPT_PTR },
     { "naptr-record", 1, 0, LOPT_NAPTR },
     { "bridge-interface", 1, 0 , LOPT_BRIDGE },
@@ -342,6 +344,7 @@ static struct {
   { LOPT_SECURE, OPT_TFTP_SECURE, NULL, gettext_noop("Allow access only to files owned by the user running dnsmasq."), NULL },
   { LOPT_TFTP_MAX, ARG_ONE, "<integer>", gettext_noop("Maximum number of conncurrent TFTP transfers (defaults to %s)."), "#" },
   { LOPT_NOBLOCK, OPT_TFTP_NOBLOCK, NULL, gettext_noop("Disable the TFTP blocksize extension."), NULL },
+  { LOPT_TFTP_LC, OPT_TFTP_LC, NULL, gettext_noop("Convert TFTP filenames to lowercase"), NULL },
   { LOPT_TFTPPORTS, ARG_ONE, "<start>,<end>", gettext_noop("Ephemeral port range for use by TFTP transfers."), NULL },
   { LOPT_LOG_OPTS, OPT_LOG_OPTS, NULL, gettext_noop("Extra logging for DHCP."), NULL },
   { LOPT_MAX_LOGS, ARG_ONE, "[=<integer>]", gettext_noop("Enable async. logging; optionally set queue length."), NULL },

src/tftp.c

@@ -24,6 +24,7 @@ static ssize_t tftp_err(int err, char *packet, char *mess, char *file);
 static ssize_t tftp_err_oops(char *packet, char *file);
 static ssize_t get_block(char *packet, struct tftp_transfer *transfer);
 static char *next(char **p, char *end);
+static void sanitise(char *buf);
 
 #define OP_RRQ  1
 #define OP_WRQ  2
@@ -344,9 +345,12 @@ void tftp_request(struct listener *listen, time_t now)
 	}
 
       /* cope with backslashes from windows boxen. */
-      while ((p = strchr(filename, '\\')))
-	*p = '/';
-
+      for (p = filename; *p; p++)
+	if (*p == '\\')
+	  *p = '/';
+	else if (option_bool(OPT_TFTP_LC))
+	  *p = tolower(*p);
+		
       strcpy(daemon->namebuff, "/");
       if (prefix)
 	{
@@ -528,13 +532,7 @@ void check_tftp_listeners(fd_set *rset, time_t now)
 		  if (!err)
 		    err = "";
 		  else
-		    {
-		      unsigned char *q, *r;
-		      for (q = r = (unsigned char *)err; *r; r++)
-			if (isprint(*r))
-			  *(q++) = *r;
-		      *q = 0;
-		    }
+		    sanitise(err);
 
 		  my_syslog(MS_TFTP | LOG_ERR, _("error %d %s received from %s"),
 			    (int)ntohs(mess->block), err, 
@@ -562,27 +560,23 @@ void check_tftp_listeners(fd_set *rset, time_t now)
 	      len = tftp_err_oops(daemon->packet, transfer->file->filename);
 	      endcon = 1;
 	    }
-	  else if (++transfer->backoff > 5)
+	  /* don't complain about timeout when we're awaiting the last
+	     ACK, some clients never send it */
+	  else if (++transfer->backoff > 5 && len != 0)
 	    {
-	      /* don't complain about timeout when we're awaiting the last
-		 ACK, some clients never send it */
-	      if (len != 0)
-		{
-		  my_syslog(MS_TFTP | LOG_ERR, _("failed sending %s to %s"), 
-			    transfer->file->filename, daemon->addrbuff);
-		  len = 0;
-		  endcon = 1;
-		}
+	      endcon = 1;
+	      len = 0;
 	    }
-	  
+
 	  if (len != 0)
 	    while(sendto(transfer->sockfd, daemon->packet, len, 0, 
 			 (struct sockaddr *)&transfer->peer, sizeof(transfer->peer)) == -1 && errno == EINTR);
 	  
 	  if (endcon || len == 0)
 	    {
-	      if (!endcon)
-		my_syslog(MS_TFTP | LOG_INFO, _("sent %s to %s"), transfer->file->filename, daemon->addrbuff);
+	      strcpy(daemon->namebuff, transfer->file->filename);
+	      sanitise(daemon->namebuff);
+	      my_syslog(MS_TFTP | LOG_INFO, endcon ? _("failed sending %s to %s") : _("sent %s to %s"), daemon->namebuff, daemon->addrbuff);
 	      /* unlink */
 	      *up = tmp;
 	      /* put on queue to be sent to script and deleted */
@@ -621,6 +615,16 @@ static char *next(char **p, char *end)
   return ret;
 }
 
+static void sanitise(char *buf)
+{
+  unsigned char *q, *r;
+  for (q = r = (unsigned char *)buf; *r; r++)
+    if (isprint(*r))
+      *(q++) = *r;
+  *q = 0;
+
+}
+
 static ssize_t tftp_err(int err, char *packet, char *message, char *file)
 {
   struct errmess {
@@ -629,7 +633,9 @@ static ssize_t tftp_err(int err, char *packet, char *message, char *file)
   } *mess = (struct errmess *)packet;
   ssize_t ret = 4;
   char *errstr = strerror(errno);
- 
+  
+  sanitise(file);
+
   mess->op = htons(OP_ERR);
   mess->err = htons(err);
   ret += (snprintf(mess->message, 500,  message, file, errstr) + 1);
@@ -640,7 +646,9 @@ static ssize_t tftp_err(int err, char *packet, char *message, char *file)
 
 static ssize_t tftp_err_oops(char *packet, char *file)
 {
-  return tftp_err(ERR_NOTDEF, packet, _("cannot read %s: %s"), file);
+  /* May have >1 refs to file, so potentially mangle a copy of the name */
+  strcpy(daemon->namebuff, file);
+  return tftp_err(ERR_NOTDEF, packet, _("cannot read %s: %s"), daemon->namebuff);
 }
 
 /* return -1 for error, zero for done. */