MdeModulePkg/Library/DxeHttpLib: Handle the blank value in HTTP header.
This patch is to resolve the lock-up issue if the value of HTTP header
is blank. The issue is recorded @
https://bugzilla.tianocore.org/show_bug.cgi?id=1102.
Cc: Stephen Benjamin <stephen@redhat.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ye Ting <ting.ye@intel.com>
Cc: Fu Siyuan <siyuan.fu@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Wu Jiaxin <jiaxin.wu@intel.com>
Tested-by: Stephen Benjamin <stephen@redhat.com>
Reviewed-by: Fu Siyuan <siyuan.fu@intel.com>
diff --git a/MdeModulePkg/Library/DxeHttpLib/DxeHttpLib.c b/MdeModulePkg/Library/DxeHttpLib/DxeHttpLib.c
index 5fbb50d..2fc3da8 100644
--- a/MdeModulePkg/Library/DxeHttpLib/DxeHttpLib.c
+++ b/MdeModulePkg/Library/DxeHttpLib/DxeHttpLib.c
@@ -1597,6 +1597,18 @@
//
// Each header field consists of a name followed by a colon (":") and the field value.
+ // The field value MAY be preceded by any amount of LWS, though a single SP is preferred.
+ //
+ // message-header = field-name ":" [ field-value ]
+ // field-name = token
+ // field-value = *( field-content | LWS )
+ //
+ // Note: "*(element)" allows any number element, including zero; "1*(element)" requires at least one element.
+ // [element] means element is optional.
+ // LWS = [CRLF] 1*(SP|HT), it can be ' ' or '\t' or '\r\n ' or '\r\n\t'.
+ // CRLF = '\r\n'.
+ // SP = ' '.
+ // HT = '\t' (Tab).
//
FieldNameStr = String;
FieldValueStr = AsciiStrGetNextToken (FieldNameStr, ':');
@@ -1605,16 +1617,12 @@
}
//
- // Replace ':' with 0
+ // Replace ':' with 0, then FieldName has been retrived from String.
//
*(FieldValueStr - 1) = 0;
//
- // The field value MAY be preceded by any amount of LWS, though a single SP is preferred.
- // Note: LWS = [CRLF] 1*(SP|HT), it can be '\r\n ' or '\r\n\t' or ' ' or '\t'.
- // CRLF = '\r\n'.
- // SP = ' '.
- // HT = '\t' (Tab).
+ // Handle FieldValueStr, skip all the preceded LWS.
//
while (TRUE) {
if (*FieldValueStr == ' ' || *FieldValueStr == '\t') {
@@ -1622,6 +1630,9 @@
// Boundary condition check.
//
if ((UINTN) EndofHeader - (UINTN) FieldValueStr < 1) {
+ //
+ // Wrong String format!
+ //
return NULL;
}
@@ -1631,25 +1642,45 @@
// Boundary condition check.
//
if ((UINTN) EndofHeader - (UINTN) FieldValueStr < 3) {
- return NULL;
+ //
+ // No more preceded LWS, so break here.
+ //
+ break;
}
- if (*(FieldValueStr + 1) == '\n' && (*(FieldValueStr + 2) == ' ' || *(FieldValueStr + 2) == '\t')) {
- FieldValueStr = FieldValueStr + 3;
+ if (*(FieldValueStr + 1) == '\n' ) {
+ if (*(FieldValueStr + 2) == ' ' || *(FieldValueStr + 2) == '\t') {
+ FieldValueStr = FieldValueStr + 3;
+ } else {
+ //
+ // No more preceded LWS, so break here.
+ //
+ break;
+ }
+ } else {
+ //
+ // Wrong String format!
+ //
+ return NULL;
}
} else {
+ //
+ // No more preceded LWS, so break here.
+ //
break;
}
}
- //
- // Header fields can be extended over multiple lines by preceding each extra
- // line with at least one SP or HT.
- //
StrPtr = FieldValueStr;
do {
+ //
+ // Handle the LWS within the field value.
+ //
StrPtr = AsciiStrGetNextToken (StrPtr, '\r');
if (StrPtr == NULL || *StrPtr != '\n') {
+ //
+ // Wrong String format!
+ //
return NULL;
}
