Abort disabling old PEM keys on I/O errors.

[tinc] / src / conf.c

diff --git a/src/conf.c b/src/conf.c
index f5f6c3a..c5467d2 100644 (file)
--- a/src/conf.c
+++ b/src/conf.c
@@ -459,24 +459,33 @@ bool disable_old_keys(FILE *f) {
        rewind(f);
        pos = ftell(f);
 
+       if(pos < 0)
+               return false;
+
        while(fgets(buf, sizeof buf, f)) {
                if(!strncmp(buf, "-----BEGIN RSA", 14)) {       
                        buf[11] = 'O';
                        buf[12] = 'L';
                        buf[13] = 'D';
-                       fseek(f, pos, SEEK_SET);
-                       fputs(buf, f);
+                       if(fseek(f, pos, SEEK_SET))
+                               break;
+                       if(fputs(buf, f) <= 0)
+                               break;
                        disabled = true;
                }
                else if(!strncmp(buf, "-----END RSA", 12)) {    
                        buf[ 9] = 'O';
                        buf[10] = 'L';
                        buf[11] = 'D';
-                       fseek(f, pos, SEEK_SET);
-                       fputs(buf, f);
+                       if(fseek(f, pos, SEEK_SET))
+                               break;
+                       if(fputs(buf, f) <= 0)
+                               break;
                        disabled = true;
                }
                pos = ftell(f);
+               if(pos < 0)
+                       break;
        }
 
        return disabled;