/**
** Wrapper for PercentDecode() and handles the return values from
** PercentDecode().
**
** This really decodes the chars for UnicodeDecode(). If the char is
** a percent then we process stuff, otherwise we just increment the
** pointer and return.
**
** @param ServerConf the server configuration
** @param start the start of the URI
** @param end the end of the URI
** @param ptr the current pointer into the URI
** @param bare_byte value for a non-ASCII char or a decoded non-ASCII char
**
** @return integer
**
** @retval END_OF_BUFFER End of the buffer has been reached before decode.
** @retval NON_ASCII_CHAR End of buffer during decoding, return decoded char.
** @retval char return the valid decoded/undecoded char
**
** @see PercentDecode()
** @see GetByte()
*/
static int GetChar(HI_SESSION *Session, const u_char *start,
const u_char *end, const u_char **ptr, int *bare_byte,
URI_NORM_STATE *norm_state, uint16_t *encodeType)
{
HTTPINSPECT_CONF *ServerConf = Session->server_conf;
int iNorm;
if(!hi_util_in_bounds(start, end, *ptr))
return END_OF_BUFFER;
iNorm = (int)(**ptr);
if(**ptr == '%' && ServerConf->ascii.on)
{
/*
** We go into percent encoding.
*/
iNorm = PercentDecode(Session, start, end, ptr, norm_state, encodeType);
/*
** If during the course of PercentDecode() we run into the end
** of the buffer, then we return early (WITHOUT INCREMENTING ptr)
** with a NON_ASCII_CHAR.
*/
if(iNorm == END_OF_BUFFER)
return NON_ASCII_CHAR;
*bare_byte = 0;
}
else
{
if(ServerConf->bare_byte.on && (u_char)iNorm > 0x7f)
{
*encodeType |= HTTP_ENCODE_TYPE__BARE_BYTE;
if(hi_eo_generate_event(Session, ServerConf->bare_byte.alert) &&
!norm_state->param)
{
hi_eo_client_event_log(Session, HI_EO_CLIENT_BARE_BYTE,
NULL, NULL);
}
/*
** Set the bare_byte flag
*/
*bare_byte = 0;
}
else
{
/*
** Set the bare_byte flag negative.
*/
*bare_byte = 1;
}
}
/*
** Increment the buffer.
*/
(*ptr)++;
return iNorm;
}
// Decode a parameter value using the encoding defined in RFC 5987
//
// charset "'" [ language ] "'" value-chars
NS_IMETHODIMP
nsMIMEHeaderParamImpl::DecodeRFC5987Param(const nsACString& aParamVal,
nsACString& aLang,
nsAString& aResult)
{
nsCAutoString charset;
nsCAutoString language;
nsCAutoString value;
PRUint32 delimiters = 0;
const char *encoded = PromiseFlatCString(aParamVal).get();
const char *c = encoded;
while (*c) {
char tc = *c++;
if (tc == '\'') {
// single quote
delimiters++;
} else if (tc >= 128) {
// fail early, not ASCII
NS_WARNING("non-US-ASCII character in RFC5987-encoded param");
return NS_ERROR_INVALID_ARG;
} else {
if (delimiters == 0) {
// valid characters are checked later implicitly
charset.Append(tc);
} else if (delimiters == 1) {
// no value checking for now
language.Append(tc);
} else if (delimiters == 2) {
if (IsRFC5987AttrChar(tc)) {
value.Append(tc);
} else if (tc == '%') {
if (!IsHexDigit(c[0]) || !IsHexDigit(c[1])) {
// we expect two more characters
NS_WARNING("broken %-escape in RFC5987-encoded param");
return NS_ERROR_INVALID_ARG;
}
value.Append(tc);
// we consume two more
value.Append(*c++);
value.Append(*c++);
} else {
// character not allowed here
NS_WARNING("invalid character in RFC5987-encoded param");
return NS_ERROR_INVALID_ARG;
}
}
}
}
if (delimiters != 2) {
NS_WARNING("missing delimiters in RFC5987-encoded param");
return NS_ERROR_INVALID_ARG;
}
// abort early for unsupported encodings
if (!charset.LowerCaseEqualsLiteral("utf-8")) {
NS_WARNING("unsupported charset in RFC5987-encoded param");
return NS_ERROR_INVALID_ARG;
}
// percent-decode
if (!PercentDecode(value)) {
return NS_ERROR_OUT_OF_MEMORY;
}
// return the encoding
aLang.Assign(language);
// finally convert octet sequence to UTF-8 and be done
nsresult rv = NS_OK;
nsCOMPtr<nsIUTF8ConverterService> cvtUTF8 =
do_GetService(NS_UTF8CONVERTERSERVICE_CONTRACTID, &rv);
NS_ENSURE_SUCCESS(rv, rv);
nsCAutoString utf8;
rv = cvtUTF8->ConvertStringToUTF8(value, charset.get(), true, false, 1, utf8);
NS_ENSURE_SUCCESS(rv, rv);
CopyUTF8toUTF16(utf8, aResult);
return NS_OK;
}