Thread (55 messages) 55 messages, 2 authors, 2016-09-26

[PATCH 04/53] netfilter: nf_ct_sip: correct allowed characters in Call-ID SIP header

flat view
STALE3674d SUPERSEDED

From: Pablo Neira Ayuso <pablo@netfilter.org>
Date: 2016-09-25 23:06:14
Also in: netfilter-devel
Subsystem: netfilter, networking [general], the rest · Maintainers: Pablo Neira Ayuso, Florian Westphal, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds

Revision v1 of 117 in this series.

Revisions (117)
  1. v1
  2. v1
  3. v1
  4. v1
  5. v1
  6. v1
  7. v1
  8. v1
  9. v1
  10. v1
  11. v1
  12. v1
  13. v1
  14. v1
  15. v1
  16. v1
  17. v1
  18. v1
  19. v1
  20. v1
  21. v1
  22. v1
  23. v1
  24. v1
  25. v1
  26. v1
  27. v1
  28. v1
  29. v1
  30. v1
  31. v1
  32. v1
  33. v1
  34. v1
  35. v1
  36. v1
  37. v1
  38. v1
  39. v1
  40. v1
  41. v1 current
  42. v1
  43. v1
  44. v1
  45. v1
  46. v1
  47. v1
  48. v1
  49. v1
  50. v1
  51. v1
  52. v1
  53. v1
  54. v1
  55. v1
  56. v1
  57. v1
  58. v1
  59. v1
  60. v1
  61. v1
  62. v1
  63. v1
  64. v1
  65. v1
  66. v1
  67. v1
  68. v1
  69. v1
  70. v1
  71. v1
  72. v1
  73. v1
  74. v1
  75. v1
  76. v1
  77. v1
  78. v1
  79. v1
  80. v1
  81. v1
  82. v1
  83. v1
  84. v1
  85. v1
  86. v1
  87. v1
  88. v1
  89. v1
  90. v1
  91. v1
  92. v1
  93. v2 [diff vs current]
  94. v1
  95. v1
  96. v1
  97. v1
  98. v1
  99. v1
  100. v1
  101. v1
  102. v2 [diff vs current]
  103. v1
  104. v1
  105. v2 [diff vs current]
  106. v3 [diff vs current]
  107. v1
  108. v1
  109. v2 [diff vs current]
  110. v1
  111. v1
  112. v2 [diff vs current]
  113. v3 [diff vs current]
  114. v1
  115. v1
  116. v1
  117. v1 
From: Marco Angaroni <redacted>

Current parsing methods for SIP header Call-ID do not check correctly all
characters allowed by RFC 3261. In particular "," character is allowed
instead of "'" character. As a result Call-ID headers like the following
are discarded by IPVS SIP persistence engine.

Call-ID: -.!%*_+`'~()<>:\"/[]?{}

Above example is composed using all non-alphanumeric characters listed
in RFC 3261 for Call-ID header syntax.

Proposed fix is in nf_conntrack_sip module; function iswordc() checks this
range: (c >= '(' && c <= '/') which includes these characters: ()*+,-./
They are all allowed except ",". Instead "'" is not included in the list.

Below is an extract of relevant SIP ABNF syntax.

Call-ID  =  ( "Call-ID" / "i" ) HCOLON callid
callid   =  word [ "@" word ]

HCOLON  =  *( SP / HTAB ) ":" SWS
SWS     =  [LWS] ; sep whitespace
LWS     =  [*WSP CRLF] 1*WSP ; linear whitespace
WSP     =  SP / HTAB
word    =  1*(alphanum / "-" / "." / "!" / "%" / "*" /
           "_" / "+" / "`" / "'" / "~" /
           "(" / ")" / "<" / ">" /
           ":" / "\" / DQUOTE /
           "/" / "[" / "]" / "?" /
           "{" / "}" )

Signed-off-by: Marco Angaroni <redacted>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/netfilter/nf_conntrack_sip.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/net/netfilter/nf_conntrack_sip.c b/net/netfilter/nf_conntrack_sip.c
index 251a9a44d189..d8035351aff5 100644
--- a/net/netfilter/nf_conntrack_sip.c
+++ b/net/netfilter/nf_conntrack_sip.c
@@ -83,9 +83,10 @@ static int digits_len(const struct nf_conn *ct, const char *dptr,
 static int iswordc(const char c)
 {
 	if (isalnum(c) || c == '!' || c == '"' || c == '%' ||
-	    (c >= '(' && c <= '/') || c == ':' || c == '<' || c == '>' ||
+	    (c >= '(' && c <= '+') || c == ':' || c == '<' || c == '>' ||
 	    c == '?' || (c >= '[' && c <= ']') || c == '_' || c == '`' ||
-	    c == '{' || c == '}' || c == '~')
+	    c == '{' || c == '}' || c == '~' || (c >= '-' && c <= '/') ||
+	    c == '\'')
 		return 1;
 	return 0;
 }
-- 
2.1.4
Other recent patches touching these files
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help