[asterisk-bugs] [Asterisk 0015271]: [patch] BASE64_DECODE() adds garbage end end of decoded string

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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https://issues.asterisk.org/view.php?id=15271 
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Reported By:                chappell
Assigned To:                mnicholson
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Project:                    Asterisk
Issue ID:                   15271
Category:                   Functions/func_base64
Reproducibility:            always
Severity:                   minor
Priority:                   normal
Status:                     assigned
Asterisk Version:           1.4.24 
JIRA:                       SWP-265 
Regression:                 No 
Reviewboard Link:            
SVN Branch (only for SVN checkouts, not tarball releases): N/A 
SVN Revision (number only!):  
Request Review:              
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Date Submitted:             2009-06-04 10:16 CDT
Last Modified:              2009-11-06 10:32 CST
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Summary:                    [patch] BASE64_DECODE() adds garbage end end of
decoded string
Description: 
This problem has two causes:

1) BASE64_DECODE() fails to null terminate its return value. This becomes
evident if first a long string is decoded and then a short one.  The short
one will have have the last part of the long string appended to it.

2) What is more, ast_base64decode() does not recognize the equals signs
which pad the end of a string the length of which is not a multiple of
three bytes. Rather than stopping, it decodes the padding as data,
producing bogus output.  
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Relationships       ID      Summary
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related to          0011018 patch for 10979 breaks IAX RSA auth
related to          0010979 [path] main/util.c missed *dst='\0'; in...
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 (0113306) svnbot (reporter) - 2009-11-06 10:32
 https://issues.asterisk.org/view.php?id=15271#c113306 
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Repository: asterisk
Revision: 228378

U   branches/1.4/funcs/func_base64.c
U   branches/1.4/main/utils.c

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r228378 | mnicholson | 2009-11-06 10:32:35 -0600 (Fri, 06 Nov 2009) | 8
lines

Properly handle '=' while decoding base64 messages and null terminate
strings returned from BASE64_DECODE.

(closes issue https://issues.asterisk.org/view.php?id=15271)
Reported by: chappell
Patches:
      base64_fix.patch uploaded by chappell (license 8)
Tested by: kobaz

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http://svn.digium.com/view/asterisk?view=rev&revision=228378 

Issue History 
Date Modified    Username       Field                    Change               
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2009-11-06 10:32 svnbot         Note Added: 0113306                          
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