/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* vim:set ts=4 sw=4 sts=4 et cin: */
/* 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/. */
// HttpLog.h should generally be included first
#include "HttpLog.h"
#include "nsHttp.h"
#include "CacheControlParser.h"
#include "PLDHashTable.h"
#include "mozilla/Mutex.h"
#include "mozilla/HashFunctions.h"
#include "nsCRT.h"
#include "nsHttpRequestHead.h"
#include "nsHttpResponseHead.h"
#include "nsHttpHandler.h"
#include "nsICacheEntry.h"
#include "nsIRequest.h"
#include <errno.h>
#include <functional>
namespace mozilla {
namespace net {
// define storage for all atoms
namespace nsHttp {
#define HTTP_ATOM(_name, _value) nsHttpAtom _name = {_value};
#include "nsHttpAtomList.h"
#undef HTTP_ATOM
}
// find out how many atoms we have
#define HTTP_ATOM(_name, _value) Unused_##_name,
enum {
#include "nsHttpAtomList.h"
NUM_HTTP_ATOMS
};
#undef HTTP_ATOM
// we keep a linked list of atoms allocated on the heap for easy clean up when
// the atom table is destroyed. The structure and value string are allocated
// as one contiguous block.
struct HttpHeapAtom {
struct HttpHeapAtom *next;
char value[1];
};
static PLDHashTable *sAtomTable;
static struct HttpHeapAtom *sHeapAtoms = nullptr;
static Mutex *sLock = nullptr;
HttpHeapAtom *NewHeapAtom(const char *value) {
int len = strlen(value);
HttpHeapAtom *a = reinterpret_cast<HttpHeapAtom *>(malloc(sizeof(*a) + len));
if (!a) return nullptr;
memcpy(a->value, value, len + 1);
// add this heap atom to the list of all heap atoms
a->next = sHeapAtoms;
sHeapAtoms = a;
return a;
}
// Hash string ignore case, based on PL_HashString
static PLDHashNumber StringHash(const void *key) {
PLDHashNumber h = 0;
for (const char *s = reinterpret_cast<const char *>(key); *s; ++s)
h = AddToHash(h, nsCRT::ToLower(*s));
return h;
}
static bool StringCompare(const PLDHashEntryHdr *entry, const void *testKey) {
const void *entryKey = reinterpret_cast<const PLDHashEntryStub *>(entry)->key;
return PL_strcasecmp(reinterpret_cast<const char *>(entryKey),
reinterpret_cast<const char *>(testKey)) == 0;
}
static const PLDHashTableOps ops = {StringHash, StringCompare,
PLDHashTable::MoveEntryStub,
PLDHashTable::ClearEntryStub, nullptr};
// We put the atoms in a hash table for speedy lookup.. see ResolveAtom.
namespace nsHttp {
nsresult CreateAtomTable() {
MOZ_ASSERT(!sAtomTable, "atom table already initialized");
if (!sLock) {
sLock = new Mutex("nsHttp.sLock");
}
// The initial length for this table is a value greater than the number of
// known atoms (NUM_HTTP_ATOMS) because we expect to encounter a few random
// headers right off the bat.
sAtomTable =
new PLDHashTable(&ops, sizeof(PLDHashEntryStub), NUM_HTTP_ATOMS + 10);
// fill the table with our known atoms
const char *const atoms[] = {
#define HTTP_ATOM(_name, _value) _name._val,
#include "nsHttpAtomList.h"
#undef HTTP_ATOM
nullptr};
for (int i = 0; atoms[i]; ++i) {
auto stub =
static_cast<PLDHashEntryStub *>(sAtomTable->Add(atoms[i], fallible));
if (!stub) return NS_ERROR_OUT_OF_MEMORY;
MOZ_ASSERT(!stub->key, "duplicate static atom");
stub->key = atoms[i];
}
return NS_OK;
}
void DestroyAtomTable() {
delete sAtomTable;
sAtomTable = nullptr;
while (sHeapAtoms) {
HttpHeapAtom *next = sHeapAtoms->next;
free(sHeapAtoms);
sHeapAtoms = next;
}
delete sLock;
sLock = nullptr;
}
Mutex *GetLock() { return sLock; }
// this function may be called from multiple threads
nsHttpAtom ResolveAtom(const char *str) {
nsHttpAtom atom = {nullptr};
if (!str || !sAtomTable) return atom;
MutexAutoLock lock(*sLock);
auto stub = static_cast<PLDHashEntryStub *>(sAtomTable->Add(str, fallible));
if (!stub) return atom; // out of memory
if (stub->key) {
atom._val = reinterpret_cast<const char *>(stub->key);
return atom;
}
// if the atom could not be found in the atom table, then we'll go
// and allocate a new atom on the heap.
HttpHeapAtom *heapAtom = NewHeapAtom(str);
if (!heapAtom) return atom; // out of memory
stub->key = atom._val = heapAtom->value;
return atom;
}
//
// From section 2.2 of RFC 2616, a token is defined as:
//
// token = 1*<any CHAR except CTLs or separators>
// CHAR = <any US-ASCII character (octets 0 - 127)>
// separators = "(" | ")" | "<" | ">" | "@"
// | "," | ";" | ":" | "\" | <">
// | "/" | "[" | "]" | "?" | "="
// | "{" | "}" | SP | HT
// CTL = <any US-ASCII control character
// (octets 0 - 31) and DEL (127)>
// SP = <US-ASCII SP, space (32)>
// HT = <US-ASCII HT, horizontal-tab (9)>
//
static const char kValidTokenMap[128] = {
0, 0, 0, 0, 0, 0, 0, 0, // 0
0, 0, 0, 0, 0, 0, 0, 0, // 8
0, 0, 0, 0, 0, 0, 0, 0, // 16
0, 0, 0, 0, 0, 0, 0, 0, // 24
0, 1, 0, 1, 1, 1, 1, 1, // 32
0, 0, 1, 1, 0, 1, 1, 0, // 40
1, 1, 1, 1, 1, 1, 1, 1, // 48
1, 1, 0, 0, 0, 0, 0, 0, // 56
0, 1, 1, 1, 1, 1, 1, 1, // 64
1, 1, 1, 1, 1, 1, 1, 1, // 72
1, 1, 1, 1, 1, 1, 1, 1, // 80
1, 1, 1, 0, 0, 0, 1, 1, // 88
1, 1, 1, 1, 1, 1, 1, 1, // 96
1, 1, 1, 1, 1, 1, 1, 1, // 104
1, 1, 1, 1, 1, 1, 1, 1, // 112
1, 1, 1, 0, 1, 0, 1, 0 // 120
};
bool IsValidToken(const char *start, const char *end) {
if (start == end) return false;
for (; start != end; ++start) {
const unsigned char idx = *start;
if (idx > 127 || !kValidTokenMap[idx]) return false;
}
return true;
}
const char *GetProtocolVersion(uint32_t pv) {
switch (pv) {
case HTTP_VERSION_2:
case NS_HTTP_VERSION_2_0:
return "h2";
case NS_HTTP_VERSION_1_0:
return "http/1.0";
case NS_HTTP_VERSION_1_1:
return "http/1.1";
default:
NS_WARNING(nsPrintfCString("Unkown protocol version: 0x%X. "
"Please file a bug",
pv)
.get());
return "http/1.1";
}
}
// static
void TrimHTTPWhitespace(const nsACString &aSource, nsACString &aDest) {
nsAutoCString str(aSource);
// HTTP whitespace 0x09: '\t', 0x0A: '\n', 0x0D: '\r', 0x20: ' '
static const char kHTTPWhitespace[] = "\t\n\r ";
str.Trim(kHTTPWhitespace);
aDest.Assign(str);
}
// static
bool IsReasonableHeaderValue(const nsACString &s) {
// Header values MUST NOT contain line-breaks. RFC 2616 technically
// permits CTL characters, including CR and LF, in header values provided
// they are quoted. However, this can lead to problems if servers do not
// interpret quoted strings properly. Disallowing CR and LF here seems
// reasonable and keeps things simple. We also disallow a null byte.
const nsACString::char_type *end = s.EndReading();
for (const nsACString::char_type *i = s.BeginReading(); i != end; ++i) {
if (*i == '\r' || *i == '\n' || *i == '\0') {
return false;
}
}
return true;
}
const char *FindToken(const char *input, const char *token, const char *seps) {
if (!input) return nullptr;
int inputLen = strlen(input);
int tokenLen = strlen(token);
if (inputLen < tokenLen) return nullptr;
const char *inputTop = input;
const char *inputEnd = input + inputLen - tokenLen;
for (; input <= inputEnd; ++input) {
if (PL_strncasecmp(input, token, tokenLen) == 0) {
if (input > inputTop && !strchr(seps, *(input - 1))) continue;
if (input < inputEnd && !strchr(seps, *(input + tokenLen))) continue;
return input;
}
}
return nullptr;
}
bool ParseInt64(const char *input, const char **next, int64_t *r) {
MOZ_ASSERT(input);
MOZ_ASSERT(r);
char *end = nullptr;
errno = 0; // Clear errno to make sure its value is set by strtoll
int64_t value = strtoll(input, &end, /* base */ 10);
// Fail if: - the parsed number overflows.
// - the end points to the start of the input string.
// - we parsed a negative value. Consumers don't expect that.
if (errno != 0 || end == input || value < 0) {
LOG(("nsHttp::ParseInt64 value=%" PRId64 " errno=%d", value, errno));
return false;
}
if (next) {
*next = end;
}
*r = value;
return true;
}
bool IsPermanentRedirect(uint32_t httpStatus) {
return httpStatus == 301 || httpStatus == 308;
}
bool ValidationRequired(bool isForcedValid,
nsHttpResponseHead *cachedResponseHead,
uint32_t loadFlags, bool allowStaleCacheContent,
bool isImmutable, bool customConditionalRequest,
nsHttpRequestHead &requestHead, nsICacheEntry *entry,
CacheControlParser &cacheControlRequest,
bool fromPreviousSession) {
// Check isForcedValid to see if it is possible to skip validation.
// Don't skip validation if we have serious reason to believe that this
// content is invalid (it's expired).
// See netwerk/cache2/nsICacheEntry.idl for details
if (isForcedValid && (!cachedResponseHead->ExpiresInPast() ||
!cachedResponseHead->MustValidateIfExpired())) {
LOG(("NOT validating based on isForcedValid being true.\n"));
return false;
}
// If the LOAD_FROM_CACHE flag is set, any cached data can simply be used
if (loadFlags & nsIRequest::LOAD_FROM_CACHE || allowStaleCacheContent) {
LOG(("NOT validating based on LOAD_FROM_CACHE load flag\n"));
return false;
}
// If the VALIDATE_ALWAYS flag is set, any cached data won't be used until
// it's revalidated with the server.
if ((loadFlags & nsIRequest::VALIDATE_ALWAYS) && !isImmutable) {
LOG(("Validating based on VALIDATE_ALWAYS load flag\n"));
return true;
}
// Even if the VALIDATE_NEVER flag is set, there are still some cases in
// which we must validate the cached response with the server.
if (loadFlags & nsIRequest::VALIDATE_NEVER) {
LOG(("VALIDATE_NEVER set\n"));
// if no-store validate cached response (see bug 112564)
if (cachedResponseHead->NoStore()) {
LOG(("Validating based on no-store logic\n"));
return true;
} else {
LOG(("NOT validating based on VALIDATE_NEVER load flag\n"));
return false;
}
}
// check if validation is strictly required...
if (cachedResponseHead->MustValidate()) {
LOG(("Validating based on MustValidate() returning TRUE\n"));
return true;
}
// possibly serve from cache for a custom If-Match/If-Unmodified-Since
// conditional request
if (customConditionalRequest && !requestHead.HasHeader(nsHttp::If_Match) &&
!requestHead.HasHeader(nsHttp::If_Unmodified_Since)) {
LOG(("Validating based on a custom conditional request\n"));
return true;
}
// previously we also checked for a query-url w/out expiration
// and didn't do heuristic on it. but defacto that is allowed now.
//
// Check if the cache entry has expired...
bool doValidation = true;
uint32_t now = NowInSeconds();
uint32_t age = 0;
nsresult rv = cachedResponseHead->ComputeCurrentAge(now, now, &age);
if (NS_FAILED(rv)) {
return true;
}
uint32_t freshness = 0;
rv = cachedResponseHead->ComputeFreshnessLifetime(&freshness);
if (NS_FAILED(rv)) {
return true;
}
uint32_t expiration = 0;
rv = entry->GetExpirationTime(&expiration);
if (NS_FAILED(rv)) {
return true;
}
uint32_t maxAgeRequest, maxStaleRequest, minFreshRequest;
LOG((" NowInSeconds()=%u, expiration time=%u, freshness lifetime=%u, age=%u",
now, expiration, freshness, age));
if (cacheControlRequest.NoCache()) {
LOG((" validating, no-cache request"));
doValidation = true;
} else if (cacheControlRequest.MaxStale(&maxStaleRequest)) {
uint32_t staleTime = age > freshness ? age - freshness : 0;
doValidation = staleTime > maxStaleRequest;
LOG((" validating=%d, max-stale=%u requested", doValidation,
maxStaleRequest));
} else if (cacheControlRequest.MaxAge(&maxAgeRequest)) {
doValidation = age > maxAgeRequest;
LOG((" validating=%d, max-age=%u requested", doValidation, maxAgeRequest));
} else if (cacheControlRequest.MinFresh(&minFreshRequest)) {
uint32_t freshTime = freshness > age ? freshness - age : 0;
doValidation = freshTime < minFreshRequest;
LOG((" validating=%d, min-fresh=%u requested", doValidation,
minFreshRequest));
} else if (now <= expiration) {
doValidation = false;
LOG((" not validating, expire time not in the past"));
} else if (cachedResponseHead->MustValidateIfExpired()) {
doValidation = true;
} else if (loadFlags & nsIRequest::VALIDATE_ONCE_PER_SESSION) {
// If the cached response does not include expiration infor-
// mation, then we must validate the response, despite whether
// or not this is the first access this session. This behavior
// is consistent with existing browsers and is generally expected
// by web authors.
if (freshness == 0)
doValidation = true;
else
doValidation = fromPreviousSession;
} else {
doValidation = true;
}
LOG(("%salidating based on expiration time\n", doValidation ? "V" : "Not v"));
return doValidation;
}
nsresult GetHttpResponseHeadFromCacheEntry(
nsICacheEntry *entry, nsHttpResponseHead *cachedResponseHead) {
nsCString buf;
// A "original-response-headers" metadata element holds network original
// headers, i.e. the headers in the form as they arrieved from the network. We
// need to get the network original headers first, because we need to keep
// them in order.
nsresult rv = entry->GetMetaDataElement("original-response-headers",
getter_Copies(buf));
if (NS_SUCCEEDED(rv)) {
rv = cachedResponseHead->ParseCachedOriginalHeaders((char *)buf.get());
if (NS_FAILED(rv)) {
LOG((" failed to parse original-response-headers\n"));
}
}
buf.Adopt(0);
// A "response-head" metadata element holds response head, e.g. response
// status line and headers in the form Firefox uses them internally (no
// dupicate headers, etc.).
rv = entry->GetMetaDataElement("response-head", getter_Copies(buf));
NS_ENSURE_SUCCESS(rv, rv);
// Parse string stored in a "response-head" metadata element.
// These response headers will be merged with the orignal headers (i.e. the
// headers stored in a "original-response-headers" metadata element).
rv = cachedResponseHead->ParseCachedHead(buf.get());
NS_ENSURE_SUCCESS(rv, rv);
buf.Adopt(0);
return NS_OK;
}
nsresult CheckPartial(nsICacheEntry *aEntry, int64_t *aSize,
int64_t *aContentLength,
nsHttpResponseHead *responseHead) {
nsresult rv;
rv = aEntry->GetDataSize(aSize);
if (NS_ERROR_IN_PROGRESS == rv) {
*aSize = -1;
rv = NS_OK;
}
NS_ENSURE_SUCCESS(rv, rv);
if (!responseHead) {
return NS_ERROR_UNEXPECTED;
}
*aContentLength = responseHead->ContentLength();
return NS_OK;
}
void DetermineFramingAndImmutability(nsICacheEntry *entry,
nsHttpResponseHead *responseHead,
bool isHttps, bool *weaklyFramed,
bool *isImmutable) {
nsCString framedBuf;
nsresult rv =
entry->GetMetaDataElement("strongly-framed", getter_Copies(framedBuf));
// describe this in terms of explicitly weakly framed so as to be backwards
// compatible with old cache contents which dont have strongly-framed makers
*weaklyFramed = NS_SUCCEEDED(rv) && framedBuf.EqualsLiteral("0");
*isImmutable = !*weaklyFramed && isHttps && responseHead->Immutable();
}
bool IsBeforeLastActiveTabLoadOptimization(TimeStamp const &when) {
return gHttpHandler &&
gHttpHandler->IsBeforeLastActiveTabLoadOptimization(when);
}
void NotifyActiveTabLoadOptimization() {
if (gHttpHandler) {
gHttpHandler->NotifyActiveTabLoadOptimization();
}
}
TimeStamp const GetLastActiveTabLoadOptimizationHit() {
return gHttpHandler ? gHttpHandler->GetLastActiveTabLoadOptimizationHit()
: TimeStamp();
}
void SetLastActiveTabLoadOptimizationHit(TimeStamp const &when) {
if (gHttpHandler) {
gHttpHandler->SetLastActiveTabLoadOptimizationHit(when);
}
}
} // namespace nsHttp
template <typename T>
void localEnsureBuffer(UniquePtr<T[]> &buf, uint32_t newSize, uint32_t preserve,
uint32_t &objSize) {
if (objSize >= newSize) return;
// Leave a little slop on the new allocation - add 2KB to
// what we need and then round the result up to a 4KB (page)
// boundary.
objSize = (newSize + 2048 + 4095) & ~4095;
static_assert(sizeof(T) == 1, "sizeof(T) must be 1");
auto tmp = MakeUnique<T[]>(objSize);
if (preserve) {
memcpy(tmp.get(), buf.get(), preserve);
}
buf = Move(tmp);
}
void EnsureBuffer(UniquePtr<char[]> &buf, uint32_t newSize, uint32_t preserve,
uint32_t &objSize) {
localEnsureBuffer<char>(buf, newSize, preserve, objSize);
}
void EnsureBuffer(UniquePtr<uint8_t[]> &buf, uint32_t newSize,
uint32_t preserve, uint32_t &objSize) {
localEnsureBuffer<uint8_t>(buf, newSize, preserve, objSize);
}
static bool IsTokenSymbol(signed char chr) {
if (chr < 33 || chr == 127 || chr == '(' || chr == ')' || chr == '<' ||
chr == '>' || chr == '@' || chr == ',' || chr == ';' || chr == ':' ||
chr == '"' || chr == '/' || chr == '[' || chr == ']' || chr == '?' ||
chr == '=' || chr == '{' || chr == '}' || chr == '\\') {
return false;
}
return true;
}
ParsedHeaderPair::ParsedHeaderPair(const char *name, int32_t nameLen,
const char *val, int32_t valLen,
bool isQuotedValue)
: mName(nsDependentCSubstring(nullptr, 0u)),
mValue(nsDependentCSubstring(nullptr, 0u)),
mIsQuotedValue(isQuotedValue) {
if (nameLen > 0) {
mName.Rebind(name, name + nameLen);
}
if (valLen > 0) {
if (mIsQuotedValue) {
RemoveQuotedStringEscapes(val, valLen);
mValue.Rebind(mUnquotedValue.BeginWriting(), mUnquotedValue.Length());
} else {
mValue.Rebind(val, val + valLen);
}
}
}
void ParsedHeaderPair::RemoveQuotedStringEscapes(const char *val,
int32_t valLen) {
mUnquotedValue.Truncate();
const char *c = val;
for (int32_t i = 0; i < valLen; ++i) {
if (c[i] == '\\' && c[i + 1]) {
++i;
}
mUnquotedValue.Append(c[i]);
}
}
static void Tokenize(
const char *input, uint32_t inputLen, const char token,
const std::function<void(const char *, uint32_t)> &consumer) {
auto trimWhitespace = [](const char *in, uint32_t inLen, const char **out,
uint32_t *outLen) {
*out = in;
*outLen = inLen;
if (inLen == 0) {
return;
}
// Trim leading space
while (nsCRT::IsAsciiSpace(**out)) {
(*out)++;
--(*outLen);
}
// Trim tailing space
for (const char *i = *out + *outLen - 1; i >= *out; --i) {
if (!nsCRT::IsAsciiSpace(*i)) {
break;
}
--(*outLen);
}
};
const char *first = input;
bool inQuote = false;
const char *result = nullptr;
uint32_t resultLen = 0;
for (uint32_t index = 0; index < inputLen; ++index) {
if (inQuote && input[index] == '\\' && input[index + 1]) {
index++;
continue;
}
if (input[index] == '"') {
inQuote = !inQuote;
continue;
}
if (inQuote) {
continue;
}
if (input[index] == token) {
trimWhitespace(first, (input + index) - first, &result, &resultLen);
consumer(result, resultLen);
first = input + index + 1;
}
}
trimWhitespace(first, (input + inputLen) - first, &result, &resultLen);
consumer(result, resultLen);
}
ParsedHeaderValueList::ParsedHeaderValueList(const char *t, uint32_t len,
bool allowInvalidValue) {
if (!len) {
return;
}
ParsedHeaderValueList *self = this;
auto consumer = [=](const char *output, uint32_t outputLength) {
self->ParseNameAndValue(output, allowInvalidValue);
};
Tokenize(t, len, ';', consumer);
}
void ParsedHeaderValueList::ParseNameAndValue(const char *input,
bool allowInvalidValue) {
const char *nameStart = input;
const char *nameEnd = nullptr;
const char *valueStart = input;
const char *valueEnd = nullptr;
bool isQuotedString = false;
bool invalidValue = false;
for (; *input && *input != ';' && *input != ',' &&
!nsCRT::IsAsciiSpace(*input) && *input != '=';
input++)
;
nameEnd = input;
if (!(nameEnd - nameStart)) {
return;
}
// Check whether param name is a valid token.
for (const char *c = nameStart; c < nameEnd; c++) {
if (!IsTokenSymbol(*c)) {
nameEnd = c;
break;
}
}
if (!(nameEnd - nameStart)) {
return;
}
while (nsCRT::IsAsciiSpace(*input)) {
++input;
}
if (!*input || *input++ != '=') {
mValues.AppendElement(
ParsedHeaderPair(nameStart, nameEnd - nameStart, nullptr, 0, false));
return;
}
while (nsCRT::IsAsciiSpace(*input)) {
++input;
}
if (*input != '"') {
// The value is a token, not a quoted string.
valueStart = input;
for (valueEnd = input; *valueEnd && !nsCRT::IsAsciiSpace(*valueEnd) &&
*valueEnd != ';' && *valueEnd != ',';
valueEnd++)
;
input = valueEnd;
if (!allowInvalidValue) {
for (const char *c = valueStart; c < valueEnd; c++) {
if (!IsTokenSymbol(*c)) {
valueEnd = c;
break;
}
}
}
} else {
bool foundQuotedEnd = false;
isQuotedString = true;
++input;
valueStart = input;
for (valueEnd = input; *valueEnd; ++valueEnd) {
if (*valueEnd == '\\' && *(valueEnd + 1)) {
++valueEnd;
} else if (*valueEnd == '"') {
foundQuotedEnd = true;
break;
}
}
if (!foundQuotedEnd) {
invalidValue = true;
}
input = valueEnd;
// *valueEnd != null means that *valueEnd is quote character.
if (*valueEnd) {
input++;
}
}
if (invalidValue) {
valueEnd = valueStart;
}
mValues.AppendElement(ParsedHeaderPair(nameStart, nameEnd - nameStart,
valueStart, valueEnd - valueStart,
isQuotedString));
}
ParsedHeaderValueListList::ParsedHeaderValueListList(
const nsCString &fullHeader, bool allowInvalidValue)
: mFull(fullHeader) {
auto &values = mValues;
auto consumer = [&values, allowInvalidValue](const char *output,
uint32_t outputLength) {
values.AppendElement(
ParsedHeaderValueList(output, outputLength, allowInvalidValue));
};
Tokenize(mFull.BeginReading(), mFull.Length(), ',', consumer);
}
} // namespace net
} // namespace mozilla