allow trimming expressions with ${foo#bar} syntax in nslcd

1 files changed, 62 insertions, 0 deletions

diff --git a/common/expr.c b/common/expr.c
index 97fcff8..a71a5e9 100644
--- a/common/expr.c
+++ b/common/expr.c
@@ -3,6 +3,7 @@
    This file is part of the nss-pam-ldapd library.
 
    Copyright (C) 2009, 2010, 2011, 2012 Arthur de Jong
+   Copyright (c) 2012 Thorsten Glaser <t.glaser@tarent.de>
 
    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
@@ -142,6 +143,67 @@ MUST_USE static const char *parse_dollar_expression(
         buffer[0] = '\0';
       }
     }
+    else if (str[*ptr]=='#')
+    {
+      char c;
+      const char *cp, *vp;
+      int ismatch;
+      size_t vallen;
+
+      (*ptr)+=1;
+      cp=str+*ptr;
+      vp=varvalue;
+      ismatch=1;
+      while ((c=*cp++) && c!='}')
+      {
+        if (ismatch && !*vp)
+        {
+          /* varvalue shorter than trim string */
+          ismatch=0;
+        }
+        if (c=='?')
+        {
+          /* match any one character */
+          ++vp;
+          continue;
+        }
+        if (c=='\\')
+        {
+          if (!(c=*cp++))
+          {
+            /* end of input: syntax error */
+            return NULL;
+          }
+          /* escape the next character c */
+        }
+        if (ismatch && *vp!=c)
+        {
+          /* they differ */
+          ismatch=0;
+        }
+        ++vp;
+      }
+      if (!c)
+      {
+        /* end of input: syntax error */
+        return NULL;
+      }
+      /*
+       * at this point, cp points to after the closing }
+       * if ismatch, vp points to the beginning of the
+       * data after trimming, otherwise vp is invalid
+       */
+      --cp;
+      (*ptr)=cp-str;
+      if (!ismatch)
+      {
+        vp=varvalue;
+      }
+      /* now copy the (trimmed or not) value to the buffer */
+      if ((vallen=strlen(vp)+1)>buflen)
+        return NULL;
+      memcpy(buffer,vp,vallen);
+    }
     else
       return NULL;
     (*ptr)++; /* skip closing } */