/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ /* vim: set sw=4 ts=8 et tw=80 : */ /* This Source Code Form is subject to the terms of the Mozilla Public * License, v. 2.0. If a copy of the MPL was not distributed with this * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ #include <string.h> #include "prmem.h" #include "prprf.h" #include "plstr.h" #include "plbase64.h" #include "nsCRT.h" #include "nsMemory.h" #include "nsTArray.h" #include "nsCOMPtr.h" #include "nsEscape.h" #include "nsIUTF8ConverterService.h" #include "nsUConvCID.h" #include "nsIServiceManager.h" #include "nsMIMEHeaderParamImpl.h" #include "nsReadableUtils.h" #include "nsNativeCharsetUtils.h" #include "nsError.h" #include "nsIUnicodeDecoder.h" #include "mozilla/dom/EncodingUtils.h" using mozilla::dom::EncodingUtils; // static functions declared below are moved from mailnews/mime/src/comi18n.cpp static char *DecodeQ(const char *, uint32_t); static bool Is7bitNonAsciiString(const char *, uint32_t); static void CopyRawHeader(const char *, uint32_t, const char *, nsACString &); static nsresult DecodeRFC2047Str(const char *, const char *, bool, nsACString&); static nsresult internalDecodeParameter(const nsACString&, const char*, const char*, bool, bool, nsACString&); // XXX The chance of UTF-7 being used in the message header is really // low, but in theory it's possible. #define IS_7BIT_NON_ASCII_CHARSET(cset) \ (!nsCRT::strncasecmp((cset), "ISO-2022", 8) || \ !nsCRT::strncasecmp((cset), "HZ-GB", 5) || \ !nsCRT::strncasecmp((cset), "UTF-7", 5)) NS_IMPL_ISUPPORTS(nsMIMEHeaderParamImpl, nsIMIMEHeaderParam) NS_IMETHODIMP nsMIMEHeaderParamImpl::GetParameter(const nsACString& aHeaderVal, const char *aParamName, const nsACString& aFallbackCharset, bool aTryLocaleCharset, char **aLang, nsAString& aResult) { return DoGetParameter(aHeaderVal, aParamName, MIME_FIELD_ENCODING, aFallbackCharset, aTryLocaleCharset, aLang, aResult); } NS_IMETHODIMP nsMIMEHeaderParamImpl::GetParameterHTTP(const nsACString& aHeaderVal, const char *aParamName, const nsACString& aFallbackCharset, bool aTryLocaleCharset, char **aLang, nsAString& aResult) { return DoGetParameter(aHeaderVal, aParamName, HTTP_FIELD_ENCODING, aFallbackCharset, aTryLocaleCharset, aLang, aResult); } // XXX : aTryLocaleCharset is not yet effective. nsresult nsMIMEHeaderParamImpl::DoGetParameter(const nsACString& aHeaderVal, const char *aParamName, ParamDecoding aDecoding, const nsACString& aFallbackCharset, bool aTryLocaleCharset, char **aLang, nsAString& aResult) { aResult.Truncate(); nsresult rv; // get parameter (decode RFC 2231/5987 when applicable, as specified by // aDecoding (5987 being a subset of 2231) and return charset.) nsXPIDLCString med; nsXPIDLCString charset; rv = DoParameterInternal(PromiseFlatCString(aHeaderVal).get(), aParamName, aDecoding, getter_Copies(charset), aLang, getter_Copies(med)); if (NS_FAILED(rv)) return rv; // convert to UTF-8 after charset conversion and RFC 2047 decoding // if necessary. nsAutoCString str1; rv = internalDecodeParameter(med, charset.get(), nullptr, false, // was aDecoding == MIME_FIELD_ENCODING // see bug 875615 true, str1); NS_ENSURE_SUCCESS(rv, rv); if (!aFallbackCharset.IsEmpty()) { nsAutoCString charset; EncodingUtils::FindEncodingForLabel(aFallbackCharset, charset); nsAutoCString str2; nsCOMPtr<nsIUTF8ConverterService> cvtUTF8(do_GetService(NS_UTF8CONVERTERSERVICE_CONTRACTID)); if (cvtUTF8 && NS_SUCCEEDED(cvtUTF8->ConvertStringToUTF8(str1, PromiseFlatCString(aFallbackCharset).get(), false, !charset.EqualsLiteral("UTF-8"), 1, str2))) { CopyUTF8toUTF16(str2, aResult); return NS_OK; } } if (IsUTF8(str1)) { CopyUTF8toUTF16(str1, aResult); return NS_OK; } if (aTryLocaleCharset && !NS_IsNativeUTF8()) return NS_CopyNativeToUnicode(str1, aResult); CopyASCIItoUTF16(str1, aResult); return NS_OK; } // remove backslash-encoded sequences from quoted-strings // modifies string in place, potentially shortening it void RemoveQuotedStringEscapes(char *src) { char *dst = src; for (char *c = src; *c; ++c) { if (c[0] == '\\' && c[1]) { // skip backslash if not at end ++c; } *dst++ = *c; } *dst = 0; } // true is character is a hex digit bool IsHexDigit(char aChar) { char c = aChar; return (c >= 'a' && c <= 'f') || (c >= 'A' && c <= 'F') || (c >= '0' && c <= '9'); } // validate that a C String containing %-escapes is syntactically valid bool IsValidPercentEscaped(const char *aValue, int32_t len) { for (int32_t i = 0; i < len; i++) { if (aValue[i] == '%') { if (!IsHexDigit(aValue[i + 1]) || !IsHexDigit(aValue[i + 2])) { return false; } } } return true; } // Support for continuations (RFC 2231, Section 3) // only a sane number supported #define MAX_CONTINUATIONS 999 // part of a continuation class Continuation { public: Continuation(const char *aValue, uint32_t aLength, bool aNeedsPercentDecoding, bool aWasQuotedString) { value = aValue; length = aLength; needsPercentDecoding = aNeedsPercentDecoding; wasQuotedString = aWasQuotedString; } Continuation() { // empty constructor needed for nsTArray value = 0L; length = 0; needsPercentDecoding = false; wasQuotedString = false; } ~Continuation() = default; const char *value; uint32_t length; bool needsPercentDecoding; bool wasQuotedString; }; // combine segments into a single string, returning the allocated string // (or nullptr) while emptying the list char *combineContinuations(nsTArray<Continuation>& aArray) { // Sanity check if (aArray.Length() == 0) return nullptr; // Get an upper bound for the length uint32_t length = 0; for (uint32_t i = 0; i < aArray.Length(); i++) { length += aArray[i].length; } // Allocate char *result = (char *) moz_xmalloc(length + 1); // Concatenate if (result) { *result = '\0'; for (uint32_t i = 0; i < aArray.Length(); i++) { Continuation cont = aArray[i]; if (! cont.value) break; char *c = result + strlen(result); strncat(result, cont.value, cont.length); if (cont.needsPercentDecoding) { nsUnescape(c); } if (cont.wasQuotedString) { RemoveQuotedStringEscapes(c); } } // return null if empty value if (*result == '\0') { free(result); result = nullptr; } } else { // Handle OOM NS_WARNING("Out of memory\n"); } return result; } // add a continuation, return false on error if segment already has been seen bool addContinuation(nsTArray<Continuation>& aArray, uint32_t aIndex, const char *aValue, uint32_t aLength, bool aNeedsPercentDecoding, bool aWasQuotedString) { if (aIndex < aArray.Length() && aArray[aIndex].value) { NS_WARNING("duplicate RC2231 continuation segment #\n"); return false; } if (aIndex > MAX_CONTINUATIONS) { NS_WARNING("RC2231 continuation segment # exceeds limit\n"); return false; } if (aNeedsPercentDecoding && aWasQuotedString) { NS_WARNING("RC2231 continuation segment can't use percent encoding and quoted string form at the same time\n"); return false; } Continuation cont(aValue, aLength, aNeedsPercentDecoding, aWasQuotedString); if (aArray.Length() <= aIndex) { aArray.SetLength(aIndex + 1); } aArray[aIndex] = cont; return true; } // parse a segment number; return -1 on error int32_t parseSegmentNumber(const char *aValue, int32_t aLen) { if (aLen < 1) { NS_WARNING("segment number missing\n"); return -1; } if (aLen > 1 && aValue[0] == '0') { NS_WARNING("leading '0' not allowed in segment number\n"); return -1; } int32_t segmentNumber = 0; for (int32_t i = 0; i < aLen; i++) { if (! (aValue[i] >= '0' && aValue[i] <= '9')) { NS_WARNING("invalid characters in segment number\n"); return -1; } segmentNumber *= 10; segmentNumber += aValue[i] - '0'; if (segmentNumber > MAX_CONTINUATIONS) { NS_WARNING("Segment number exceeds sane size\n"); return -1; } } return segmentNumber; } // validate a given octet sequence for compliance with the specified // encoding bool IsValidOctetSequenceForCharset(nsACString& aCharset, const char *aOctets) { nsCOMPtr<nsIUTF8ConverterService> cvtUTF8(do_GetService (NS_UTF8CONVERTERSERVICE_CONTRACTID)); if (!cvtUTF8) { NS_WARNING("Can't get UTF8ConverterService\n"); return false; } nsAutoCString tmpRaw; tmpRaw.Assign(aOctets); nsAutoCString tmpDecoded; nsresult rv = cvtUTF8->ConvertStringToUTF8(tmpRaw, PromiseFlatCString(aCharset).get(), false, false, 1, tmpDecoded); if (rv != NS_OK) { // we can't decode; charset may be unsupported, or the octet sequence // is broken (illegal or incomplete octet sequence contained) NS_WARNING("RFC2231/5987 parameter value does not decode according to specified charset\n"); return false; } return true; } // moved almost verbatim from mimehdrs.cpp // char * // MimeHeaders_get_parameter (const char *header_value, const char *parm_name, // char **charset, char **language) // // The format of these header lines is // <token> [ ';' <token> '=' <token-or-quoted-string> ]* NS_IMETHODIMP nsMIMEHeaderParamImpl::GetParameterInternal(const char *aHeaderValue, const char *aParamName, char **aCharset, char **aLang, char **aResult) { return DoParameterInternal(aHeaderValue, aParamName, MIME_FIELD_ENCODING, aCharset, aLang, aResult); } nsresult nsMIMEHeaderParamImpl::DoParameterInternal(const char *aHeaderValue, const char *aParamName, ParamDecoding aDecoding, char **aCharset, char **aLang, char **aResult) { if (!aHeaderValue || !*aHeaderValue || !aResult) return NS_ERROR_INVALID_ARG; *aResult = nullptr; if (aCharset) *aCharset = nullptr; if (aLang) *aLang = nullptr; nsAutoCString charset; // change to (aDecoding != HTTP_FIELD_ENCODING) when we want to disable // them for HTTP header fields later on, see bug 776324 bool acceptContinuations = true; const char *str = aHeaderValue; // skip leading white space. for (; *str && nsCRT::IsAsciiSpace(*str); ++str) ; const char *start = str; // aParamName is empty. return the first (possibly) _unnamed_ 'parameter' // For instance, return 'inline' in the following case: // Content-Disposition: inline; filename=..... if (!aParamName || !*aParamName) { for (; *str && *str != ';' && !nsCRT::IsAsciiSpace(*str); ++str) ; if (str == start) return NS_ERROR_FIRST_HEADER_FIELD_COMPONENT_EMPTY; *aResult = (char *) nsMemory::Clone(start, (str - start) + 1); NS_ENSURE_TRUE(*aResult, NS_ERROR_OUT_OF_MEMORY); (*aResult)[str - start] = '\0'; // null-terminate return NS_OK; } /* Skip forward to first ';' */ for (; *str && *str != ';' && *str != ','; ++str) ; if (*str) str++; /* Skip over following whitespace */ for (; *str && nsCRT::IsAsciiSpace(*str); ++str) ; // Some broken http servers just specify parameters // like 'filename' without specifying disposition // method. Rewind to the first non-white-space // character. if (!*str) str = start; // RFC2231 - The legitimate parm format can be: // A. title=ThisIsTitle // B. title*=us-ascii'en-us'This%20is%20wierd. // C. title*0*=us-ascii'en'This%20is%20wierd.%20We // title*1*=have%20to%20support%20this. // title*2="Else..." // D. title*0="Hey, what you think you are doing?" // title*1="There is no charset and lang info." // RFC5987: only A and B // collect results for the different algorithms (plain filename, // RFC5987/2231-encoded filename, + continuations) separately and decide // which to use at the end char *caseAResult = nullptr; char *caseBResult = nullptr; char *caseCDResult = nullptr; // collect continuation segments nsTArray<Continuation> segments; // our copies of the charset parameter, kept separately as they might // differ for the two formats nsDependentCSubstring charsetB, charsetCD; nsDependentCSubstring lang; int32_t paramLen = strlen(aParamName); while (*str) { // find name/value const char *nameStart = str; const char *nameEnd = nullptr; const char *valueStart = str; const char *valueEnd = nullptr; bool isQuotedString = false; NS_ASSERTION(!nsCRT::IsAsciiSpace(*str), "should be after whitespace."); // Skip forward to the end of this token. for (; *str && !nsCRT::IsAsciiSpace(*str) && *str != '=' && *str != ';'; str++) ; nameEnd = str; int32_t nameLen = nameEnd - nameStart; // Skip over whitespace, '=', and whitespace while (nsCRT::IsAsciiSpace(*str)) ++str; if (!*str) { break; } if (*str++ != '=') { // don't accept parameters without "=" goto increment_str; } while (nsCRT::IsAsciiSpace(*str)) ++str; if (*str != '"') { // The value is a token, not a quoted string. valueStart = str; for (valueEnd = str; *valueEnd && !nsCRT::IsAsciiSpace (*valueEnd) && *valueEnd != ';'; valueEnd++) ; str = valueEnd; } else { isQuotedString = true; ++str; valueStart = str; for (valueEnd = str; *valueEnd; ++valueEnd) { if (*valueEnd == '\\' && *(valueEnd + 1)) ++valueEnd; else if (*valueEnd == '"') break; } str = valueEnd; // *valueEnd != null means that *valueEnd is quote character. if (*valueEnd) str++; } // See if this is the simplest case (case A above), // a 'single' line value with no charset and lang. // If so, copy it and return. if (nameLen == paramLen && !nsCRT::strncasecmp(nameStart, aParamName, paramLen)) { if (caseAResult) { // we already have one caseA result, ignore subsequent ones goto increment_str; } // if the parameter spans across multiple lines we have to strip out the // line continuation -- jht 4/29/98 nsAutoCString tempStr(valueStart, valueEnd - valueStart); tempStr.StripChars("\r\n"); char *res = ToNewCString(tempStr); NS_ENSURE_TRUE(res, NS_ERROR_OUT_OF_MEMORY); if (isQuotedString) RemoveQuotedStringEscapes(res); caseAResult = res; // keep going, we may find a RFC 2231/5987 encoded alternative } // case B, C, and D else if (nameLen > paramLen && !nsCRT::strncasecmp(nameStart, aParamName, paramLen) && *(nameStart + paramLen) == '*') { // 1st char past '*' const char *cp = nameStart + paramLen + 1; // if param name ends in "*" we need do to RFC5987 "ext-value" decoding bool needExtDecoding = *(nameEnd - 1) == '*'; bool caseB = nameLen == paramLen + 1; bool caseCStart = (*cp == '0') && needExtDecoding; // parse the segment number int32_t segmentNumber = -1; if (!caseB) { int32_t segLen = (nameEnd - cp) - (needExtDecoding ? 1 : 0); segmentNumber = parseSegmentNumber(cp, segLen); if (segmentNumber == -1) { acceptContinuations = false; goto increment_str; } } // CaseB and start of CaseC: requires charset and optional language // in quotes (quotes required even if lang is blank) if (caseB || (caseCStart && acceptContinuations)) { // look for single quotation mark(') const char *sQuote1 = PL_strchr(valueStart, 0x27); const char *sQuote2 = sQuote1 ? PL_strchr(sQuote1 + 1, 0x27) : nullptr; // Two single quotation marks must be present even in // absence of charset and lang. if (!sQuote1 || !sQuote2) { NS_WARNING("Mandatory two single quotes are missing in header parameter\n"); } const char *charsetStart = nullptr; int32_t charsetLength = 0; const char *langStart = nullptr; int32_t langLength = 0; const char *rawValStart = nullptr; int32_t rawValLength = 0; if (sQuote2 && sQuote1) { // both delimiters present: charSet'lang'rawVal rawValStart = sQuote2 + 1; rawValLength = valueEnd - rawValStart; langStart = sQuote1 + 1; langLength = sQuote2 - langStart; charsetStart = valueStart; charsetLength = sQuote1 - charsetStart; } else if (sQuote1) { // one delimiter; assume charset'rawVal rawValStart = sQuote1 + 1; rawValLength = valueEnd - rawValStart; charsetStart = valueStart; charsetLength = sQuote1 - valueStart; } else { // no delimiter: just rawVal rawValStart = valueStart; rawValLength = valueEnd - valueStart; } if (langLength != 0) { lang.Assign(langStart, langLength); } // keep the charset for later if (caseB) { charsetB.Assign(charsetStart, charsetLength); } else { // if caseCorD charsetCD.Assign(charsetStart, charsetLength); } // non-empty value part if (rawValLength > 0) { if (!caseBResult && caseB) { if (!IsValidPercentEscaped(rawValStart, rawValLength)) { goto increment_str; } // allocate buffer for the raw value char *tmpResult = (char *) nsMemory::Clone(rawValStart, rawValLength + 1); if (!tmpResult) { goto increment_str; } *(tmpResult + rawValLength) = 0; nsUnescape(tmpResult); caseBResult = tmpResult; } else { // caseC bool added = addContinuation(segments, 0, rawValStart, rawValLength, needExtDecoding, isQuotedString); if (!added) { // continuation not added, stop processing them acceptContinuations = false; } } } } // end of if-block : title*0*= or title*= // caseD: a line of multiline param with no need for unescaping : title*[0-9]= // or 2nd or later lines of a caseC param : title*[1-9]*= else if (acceptContinuations && segmentNumber != -1) { uint32_t valueLength = valueEnd - valueStart; bool added = addContinuation(segments, segmentNumber, valueStart, valueLength, needExtDecoding, isQuotedString); if (!added) { // continuation not added, stop processing them acceptContinuations = false; } } // end of if-block : title*[0-9]= or title*[1-9]*= } // str now points after the end of the value. // skip over whitespace, ';', whitespace. increment_str: while (nsCRT::IsAsciiSpace(*str)) ++str; if (*str == ';') { ++str; } else { // stop processing the header field; either we are done or the // separator was missing break; } while (nsCRT::IsAsciiSpace(*str)) ++str; } caseCDResult = combineContinuations(segments); if (caseBResult && !charsetB.IsEmpty()) { // check that the 2231/5987 result decodes properly given the // specified character set if (!IsValidOctetSequenceForCharset(charsetB, caseBResult)) caseBResult = nullptr; } if (caseCDResult && !charsetCD.IsEmpty()) { // check that the 2231/5987 result decodes properly given the // specified character set if (!IsValidOctetSequenceForCharset(charsetCD, caseCDResult)) caseCDResult = nullptr; } if (caseBResult) { // prefer simple 5987 format over 2231 with continuations *aResult = caseBResult; caseBResult = nullptr; charset.Assign(charsetB); } else if (caseCDResult) { // prefer 2231/5987 with or without continuations over plain format *aResult = caseCDResult; caseCDResult = nullptr; charset.Assign(charsetCD); } else if (caseAResult) { *aResult = caseAResult; caseAResult = nullptr; } // free unused stuff free(caseAResult); free(caseBResult); free(caseCDResult); // if we have a result if (*aResult) { // then return charset and lang as well if (aLang && !lang.IsEmpty()) { uint32_t len = lang.Length(); *aLang = (char *) nsMemory::Clone(lang.BeginReading(), len + 1); if (*aLang) { *(*aLang + len) = 0; } } if (aCharset && !charset.IsEmpty()) { uint32_t len = charset.Length(); *aCharset = (char *) nsMemory::Clone(charset.BeginReading(), len + 1); if (*aCharset) { *(*aCharset + len) = 0; } } } return *aResult ? NS_OK : NS_ERROR_INVALID_ARG; } nsresult internalDecodeRFC2047Header(const char* aHeaderVal, const char* aDefaultCharset, bool aOverrideCharset, bool aEatContinuations, nsACString& aResult) { aResult.Truncate(); if (!aHeaderVal) return NS_ERROR_INVALID_ARG; if (!*aHeaderVal) return NS_OK; // If aHeaderVal is RFC 2047 encoded or is not a UTF-8 string but // aDefaultCharset is specified, decodes RFC 2047 encoding and converts // to UTF-8. Otherwise, just strips away CRLF. if (PL_strstr(aHeaderVal, "=?") || (aDefaultCharset && (!IsUTF8(nsDependentCString(aHeaderVal)) || Is7bitNonAsciiString(aHeaderVal, strlen(aHeaderVal))))) { DecodeRFC2047Str(aHeaderVal, aDefaultCharset, aOverrideCharset, aResult); } else if (aEatContinuations && (PL_strchr(aHeaderVal, '\n') || PL_strchr(aHeaderVal, '\r'))) { aResult = aHeaderVal; } else { aEatContinuations = false; aResult = aHeaderVal; } if (aEatContinuations) { nsAutoCString temp(aResult); temp.ReplaceSubstring("\n\t", " "); temp.ReplaceSubstring("\r\t", " "); temp.StripChars("\r\n"); aResult = temp; } return NS_OK; } NS_IMETHODIMP nsMIMEHeaderParamImpl::DecodeRFC2047Header(const char* aHeaderVal, const char* aDefaultCharset, bool aOverrideCharset, bool aEatContinuations, nsACString& aResult) { return internalDecodeRFC2047Header(aHeaderVal, aDefaultCharset, aOverrideCharset, aEatContinuations, aResult); } // true if the character is allowed in a RFC 5987 value // see RFC 5987, Section 3.2.1, "attr-char" bool IsRFC5987AttrChar(char aChar) { char c = aChar; return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || (c >= '0' && c <= '9') || (c == '!' || c == '#' || c == '$' || c == '&' || c == '+' || c == '-' || c == '.' || c == '^' || c == '_' || c == '`' || c == '|' || c == '~'); } // percent-decode a value // returns false on failure bool PercentDecode(nsACString& aValue) { char *c = (char *) moz_xmalloc(aValue.Length() + 1); if (!c) { return false; } strcpy(c, PromiseFlatCString(aValue).get()); nsUnescape(c); aValue.Assign(c); free(c); return true; } // 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) { nsAutoCString charset; nsAutoCString language; nsAutoCString value; uint32_t delimiters = 0; const nsCString& encoded = PromiseFlatCString(aParamVal); const char *c = encoded.get(); while (*c) { char tc = *c++; if (tc == '\'') { // single quote delimiters++; } else if (((unsigned char)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); nsAutoCString utf8; rv = cvtUTF8->ConvertStringToUTF8(value, charset.get(), true, false, 1, utf8); NS_ENSURE_SUCCESS(rv, rv); CopyUTF8toUTF16(utf8, aResult); return NS_OK; } nsresult internalDecodeParameter(const nsACString& aParamValue, const char* aCharset, const char* aDefaultCharset, bool aOverrideCharset, bool aDecode2047, nsACString& aResult) { aResult.Truncate(); // If aCharset is given, aParamValue was obtained from RFC2231/5987 // encoding and we're pretty sure that it's in aCharset. if (aCharset && *aCharset) { nsCOMPtr<nsIUTF8ConverterService> cvtUTF8(do_GetService(NS_UTF8CONVERTERSERVICE_CONTRACTID)); if (cvtUTF8) return cvtUTF8->ConvertStringToUTF8(aParamValue, aCharset, true, true, 1, aResult); } const nsAFlatCString& param = PromiseFlatCString(aParamValue); nsAutoCString unQuoted; nsACString::const_iterator s, e; param.BeginReading(s); param.EndReading(e); // strip '\' when used to quote CR, LF, '"' and '\' for ( ; s != e; ++s) { if ((*s == '\\')) { if (++s == e) { --s; // '\' is at the end. move back and append '\'. } else if (*s != nsCRT::CR && *s != nsCRT::LF && *s != '"' && *s != '\\') { --s; // '\' is not foll. by CR,LF,'"','\'. move back and append '\' } // else : skip '\' and append the quoted character. } unQuoted.Append(*s); } aResult = unQuoted; nsresult rv = NS_OK; if (aDecode2047) { nsAutoCString decoded; // Try RFC 2047 encoding, instead. rv = internalDecodeRFC2047Header(unQuoted.get(), aDefaultCharset, aOverrideCharset, true, decoded); if (NS_SUCCEEDED(rv) && !decoded.IsEmpty()) aResult = decoded; } return rv; } NS_IMETHODIMP nsMIMEHeaderParamImpl::DecodeParameter(const nsACString& aParamValue, const char* aCharset, const char* aDefaultCharset, bool aOverrideCharset, nsACString& aResult) { return internalDecodeParameter(aParamValue, aCharset, aDefaultCharset, aOverrideCharset, true, aResult); } #define ISHEXCHAR(c) \ ((0x30 <= uint8_t(c) && uint8_t(c) <= 0x39) || \ (0x41 <= uint8_t(c) && uint8_t(c) <= 0x46) || \ (0x61 <= uint8_t(c) && uint8_t(c) <= 0x66)) // Decode Q encoding (RFC 2047). // static char *DecodeQ(const char *in, uint32_t length) { char *out, *dest = 0; out = dest = (char *)PR_Calloc(length + 1, sizeof(char)); if (dest == nullptr) return nullptr; while (length > 0) { unsigned c = 0; switch (*in) { case '=': // check if |in| in the form of '=hh' where h is [0-9a-fA-F]. if (length < 3 || !ISHEXCHAR(in[1]) || !ISHEXCHAR(in[2])) goto badsyntax; PR_sscanf(in + 1, "%2X", &c); *out++ = (char) c; in += 3; length -= 3; break; case '_': *out++ = ' '; in++; length--; break; default: if (*in & 0x80) goto badsyntax; *out++ = *in++; length--; } } *out++ = '\0'; for (out = dest; *out ; ++out) { if (*out == '\t') *out = ' '; } return dest; badsyntax: PR_Free(dest); return nullptr; } // check if input is HZ (a 7bit encoding for simplified Chinese : RFC 1842)) // or has ESC which may be an indication that it's in one of many ISO // 2022 7bit encodings (e.g. ISO-2022-JP(-2)/CN : see RFC 1468, 1922, 1554). // static bool Is7bitNonAsciiString(const char *input, uint32_t len) { int32_t c; enum { hz_initial, // No HZ seen yet hz_escaped, // Inside an HZ ~{ escape sequence hz_seen, // Have seen at least one complete HZ sequence hz_notpresent // Have seen something that is not legal HZ } hz_state; hz_state = hz_initial; while (len) { c = uint8_t(*input++); len--; if (c & 0x80) return false; if (c == 0x1B) return true; if (c == '~') { switch (hz_state) { case hz_initial: case hz_seen: if (*input == '{') { hz_state = hz_escaped; } else if (*input == '~') { // ~~ is the HZ encoding of ~. Skip over second ~ as well hz_state = hz_seen; input++; len--; } else { hz_state = hz_notpresent; } break; case hz_escaped: if (*input == '}') hz_state = hz_seen; break; default: break; } } } return hz_state == hz_seen; } #define REPLACEMENT_CHAR "\357\277\275" // EF BF BD (UTF-8 encoding of U+FFFD) // copy 'raw' sequences of octets in aInput to aOutput. // If aDefaultCharset is specified, the input is assumed to be in the // charset and converted to UTF-8. Otherwise, a blind copy is made. // If aDefaultCharset is specified, but the conversion to UTF-8 // is not successful, each octet is replaced by Unicode replacement // chars. *aOutput is advanced by the number of output octets. // static void CopyRawHeader(const char *aInput, uint32_t aLen, const char *aDefaultCharset, nsACString &aOutput) { int32_t c; // If aDefaultCharset is not specified, make a blind copy. if (!aDefaultCharset || !*aDefaultCharset) { aOutput.Append(aInput, aLen); return; } // Copy as long as it's US-ASCII. An ESC may indicate ISO 2022 // A ~ may indicate it is HZ while (aLen && (c = uint8_t(*aInput++)) != 0x1B && c != '~' && !(c & 0x80)) { aOutput.Append(char(c)); aLen--; } if (!aLen) { return; } aInput--; // skip ASCIIness/UTF8ness test if aInput is supected to be a 7bit non-ascii // string and aDefaultCharset is a 7bit non-ascii charset. bool skipCheck = (c == 0x1B || c == '~') && IS_7BIT_NON_ASCII_CHARSET(aDefaultCharset); // If not UTF-8, treat as default charset nsCOMPtr<nsIUTF8ConverterService> cvtUTF8(do_GetService(NS_UTF8CONVERTERSERVICE_CONTRACTID)); nsAutoCString utf8Text; if (cvtUTF8 && NS_SUCCEEDED( cvtUTF8->ConvertStringToUTF8(Substring(aInput, aInput + aLen), aDefaultCharset, skipCheck, true, 1, utf8Text))) { aOutput.Append(utf8Text); } else { // replace each octet with Unicode replacement char in UTF-8. for (uint32_t i = 0; i < aLen; i++) { c = uint8_t(*aInput++); if (c & 0x80) aOutput.Append(REPLACEMENT_CHAR); else aOutput.Append(char(c)); } } } nsresult DecodeQOrBase64Str(const char *aEncoded, size_t aLen, char aQOrBase64, const char *aCharset, nsACString &aResult) { char *decodedText; NS_ASSERTION(aQOrBase64 == 'Q' || aQOrBase64 == 'B', "Should be 'Q' or 'B'"); if(aQOrBase64 == 'Q') decodedText = DecodeQ(aEncoded, aLen); else if (aQOrBase64 == 'B') { decodedText = PL_Base64Decode(aEncoded, aLen, nullptr); } else { return NS_ERROR_INVALID_ARG; } if (!decodedText) { return NS_ERROR_INVALID_ARG; } nsresult rv; nsCOMPtr<nsIUTF8ConverterService> cvtUTF8(do_GetService(NS_UTF8CONVERTERSERVICE_CONTRACTID, &rv)); nsAutoCString utf8Text; if (NS_SUCCEEDED(rv)) { // skip ASCIIness/UTF8ness test if aCharset is 7bit non-ascii charset. rv = cvtUTF8->ConvertStringToUTF8(nsDependentCString(decodedText), aCharset, IS_7BIT_NON_ASCII_CHARSET(aCharset), true, 1, utf8Text); } PR_Free(decodedText); if (NS_FAILED(rv)) { return rv; } aResult.Append(utf8Text); return NS_OK; } static const char especials[] = R"(()<>@,;:\"/[]?.=)"; // |decode_mime_part2_str| taken from comi18n.c // Decode RFC2047-encoded words in the input and convert the result to UTF-8. // If aOverrideCharset is true, charset in RFC2047-encoded words is // ignored and aDefaultCharset is assumed, instead. aDefaultCharset // is also used to convert raw octets (without RFC 2047 encoding) to UTF-8. //static nsresult DecodeRFC2047Str(const char *aHeader, const char *aDefaultCharset, bool aOverrideCharset, nsACString &aResult) { const char *p, *q = nullptr, *r; const char *begin; // tracking pointer for where we are in the input buffer int32_t isLastEncodedWord = 0; const char *charsetStart, *charsetEnd; nsAutoCString prevCharset, curCharset; nsAutoCString encodedText; char prevEncoding = '\0', curEncoding; nsresult rv; begin = aHeader; // To avoid buffer realloc, if possible, set capacity in advance. No // matter what, more than 3x expansion can never happen for all charsets // supported by Mozilla. SCSU/BCSU with the sliding window set to a // non-BMP block may be exceptions, but Mozilla does not support them. // Neither any known mail/news program use them. Even if there's, we're // safe because we don't use a raw *char any more. aResult.SetCapacity(3 * strlen(aHeader)); while ((p = PL_strstr(begin, "=?")) != 0) { if (isLastEncodedWord) { // See if it's all whitespace. for (q = begin; q < p; ++q) { if (!PL_strchr(" \t\r\n", *q)) break; } } if (!isLastEncodedWord || q < p) { if (!encodedText.IsEmpty()) { rv = DecodeQOrBase64Str(encodedText.get(), encodedText.Length(), prevEncoding, prevCharset.get(), aResult); if (NS_FAILED(rv)) { aResult.Append(encodedText); } encodedText.Truncate(); prevCharset.Truncate(); prevEncoding = '\0'; } // copy the part before the encoded-word CopyRawHeader(begin, p - begin, aDefaultCharset, aResult); begin = p; } p += 2; // Get charset info charsetStart = p; charsetEnd = 0; for (q = p; *q != '?'; q++) { if (*q <= ' ' || PL_strchr(especials, *q)) { goto badsyntax; } // RFC 2231 section 5 if (!charsetEnd && *q == '*') { charsetEnd = q; } } if (!charsetEnd) { charsetEnd = q; } q++; curEncoding = nsCRT::ToUpper(*q); if (curEncoding != 'Q' && curEncoding != 'B') goto badsyntax; if (q[1] != '?') goto badsyntax; // loop-wise, keep going until we hit "?=". the inner check handles the // nul terminator should the string terminate before we hit the right // marker. (And the r[1] will never reach beyond the end of the string // because *r != '?' is true if r is the nul character.) for (r = q + 2; *r != '?' || r[1] != '='; r++) { if (*r < ' ') goto badsyntax; } if (r == q + 2) { // it's empty, skip begin = r + 2; isLastEncodedWord = 1; continue; } curCharset.Assign(charsetStart, charsetEnd - charsetStart); // Override charset if requested. Never override labeled UTF-8. // Use default charset instead of UNKNOWN-8BIT if ((aOverrideCharset && 0 != nsCRT::strcasecmp(curCharset.get(), "UTF-8")) || (aDefaultCharset && 0 == nsCRT::strcasecmp(curCharset.get(), "UNKNOWN-8BIT")) ) { curCharset = aDefaultCharset; } const char *R; R = r; if (curEncoding == 'B') { // bug 227290. ignore an extraneous '=' at the end. // (# of characters in B-encoded part has to be a multiple of 4) int32_t n = r - (q + 2); R -= (n % 4 == 1 && !PL_strncmp(r - 3, "===", 3)) ? 1 : 0; } // Bug 493544. Don't decode the encoded text until it ends if (R[-1] != '=' && (prevCharset.IsEmpty() || (curCharset == prevCharset && curEncoding == prevEncoding)) ) { encodedText.Append(q + 2, R - (q + 2)); prevCharset = curCharset; prevEncoding = curEncoding; begin = r + 2; isLastEncodedWord = 1; continue; } bool bDecoded; // If the current line has been decoded. bDecoded = false; if (!encodedText.IsEmpty()) { if (curCharset == prevCharset && curEncoding == prevEncoding) { encodedText.Append(q + 2, R - (q + 2)); bDecoded = true; } rv = DecodeQOrBase64Str(encodedText.get(), encodedText.Length(), prevEncoding, prevCharset.get(), aResult); if (NS_FAILED(rv)) { aResult.Append(encodedText); } encodedText.Truncate(); prevCharset.Truncate(); prevEncoding = '\0'; } if (!bDecoded) { rv = DecodeQOrBase64Str(q + 2, R - (q + 2), curEncoding, curCharset.get(), aResult); if (NS_FAILED(rv)) { aResult.Append(encodedText); } } begin = r + 2; isLastEncodedWord = 1; continue; badsyntax: if (!encodedText.IsEmpty()) { rv = DecodeQOrBase64Str(encodedText.get(), encodedText.Length(), prevEncoding, prevCharset.get(), aResult); if (NS_FAILED(rv)) { aResult.Append(encodedText); } encodedText.Truncate(); prevCharset.Truncate(); } // copy the part before the encoded-word aResult.Append(begin, p - begin); begin = p; isLastEncodedWord = 0; } if (!encodedText.IsEmpty()) { rv = DecodeQOrBase64Str(encodedText.get(), encodedText.Length(), prevEncoding, prevCharset.get(), aResult); if (NS_FAILED(rv)) { aResult.Append(encodedText); } } // put the tail back CopyRawHeader(begin, strlen(begin), aDefaultCharset, aResult); nsAutoCString tempStr(aResult); tempStr.ReplaceChar('\t', ' '); aResult = tempStr; return NS_OK; }