From: Jeremy Harris <jgh146exb@wizmail.org>
Date: Thu, 15 Oct 2015 20:40:17 +0000 (+0100)
Subject: DKIM: ignore space & tab embedded in base64 during decode.  Bug 1700
X-Git-Tag: exim-4_87_RC1~72
X-Git-Url: https://git.exim.org/exim.git/commitdiff_plain/0f557e9065b0bcfce38ee1fea5fc947bf0c5431c?ds=sidebyside

DKIM: ignore space & tab embedded in base64 during decode.  Bug 1700
---

diff --git a/doc/doc-txt/ChangeLog b/doc/doc-txt/ChangeLog
index 14f0dc737..4fb36643e 100644
--- a/doc/doc-txt/ChangeLog
+++ b/doc/doc-txt/ChangeLog
@@ -54,6 +54,10 @@ JH/07 Bug 1678: Always record an interface option value, if set,  as part of a
       different interface settings and the retry behaviour needs to be kept
       distinct.
 
+JH/08 Bug 1586: exiqgrep now refuses to run if there are unexpected arguments.
+
+JH/09 Bug 1700: ignore space & tab embedded in base64 during decode.
+
 
 Exim version 4.86
 -----------------
diff --git a/src/src/pdkim/base64.c b/src/src/pdkim/base64.c
index a82fc2d75..1395be42c 100644
--- a/src/src/pdkim/base64.c
+++ b/src/src/pdkim/base64.c
@@ -128,20 +128,22 @@ int base64_decode( unsigned char *dst, int *dlen,
 
     for( i = j = n = 0; i < slen; i++ )
     {
+	unsigned char c = src[i];
+
         if( ( slen - i ) >= 2 &&
-            src[i] == '\r' && src[i + 1] == '\n' )
+            c == '\r' && src[i + 1] == '\n' )
             continue;
 
-        if( src[i] == '\n' )
+        if( c == '\n' || c == ' ' || c == '\t' )
             continue;
 
-        if( src[i] == '=' && ++j > 2 )
+        if( c == '=' && ++j > 2 )
             return( POLARSSL_ERR_BASE64_INVALID_CHARACTER );
 
-        if( src[i] > 127 || base64_dec_map[src[i]] == 127 )
+        if( c > 127 || base64_dec_map[src[i]] == 127 )
             return( POLARSSL_ERR_BASE64_INVALID_CHARACTER );
 
-        if( base64_dec_map[src[i]] < 64 && j != 0 )
+        if( base64_dec_map[c] < 64 && j != 0 )
             return( POLARSSL_ERR_BASE64_INVALID_CHARACTER );
 
         n++;
@@ -160,11 +162,13 @@ int base64_decode( unsigned char *dst, int *dlen,
 
    for( j = 3, n = x = 0, p = dst; i > 0; i--, src++ )
    {
-        if( *src == '\r' || *src == '\n' )
+	unsigned char c = *src;
+
+        if( c == '\r' || c == '\n' || c == ' ' || c == '\t' )
             continue;
 
-        j -= ( base64_dec_map[*src] == 64 );
-        x  = (x << 6) | ( base64_dec_map[*src] & 0x3F );
+        j -= ( base64_dec_map[c] == 64 );
+        x  = (x << 6) | ( base64_dec_map[c] & 0x3F );
 
         if( ++n == 4 )
         {