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/* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
* This file is PRIVATE to SSL.
*
* 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 "nss.h"
#include "prnetdb.h"
#include "ssl.h"
#include "sslimpl.h"
#include "sslproto.h"
/* Helper function to encode an unsigned integer into a buffer. */
static void
ssl_EncodeUintX(PRUint8 *to, PRUint64 value, unsigned int bytes)
{
PRUint64 encoded;
PORT_Assert(bytes > 0 && bytes <= sizeof(encoded));
encoded = PR_htonll(value);
PORT_Memcpy(to, ((unsigned char *)(&encoded)) + (sizeof(encoded) - bytes),
bytes);
}
/* Grow a buffer to hold newLen bytes of data. When used for recv/xmit buffers,
* the caller must hold xmitBufLock or recvBufLock, as appropriate. */
SECStatus
sslBuffer_Grow(sslBuffer *b, unsigned int newLen)
{
PORT_Assert(b);
if (b->fixed) {
PORT_Assert(newLen <= b->space);
if (newLen > b->space) {
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
return SECFailure;
}
return SECSuccess;
}
newLen = PR_MAX(newLen, b->len + 1024);
if (newLen > b->space) {
unsigned char *newBuf;
if (b->buf) {
newBuf = (unsigned char *)PORT_Realloc(b->buf, newLen);
} else {
newBuf = (unsigned char *)PORT_Alloc(newLen);
}
if (!newBuf) {
return SECFailure;
}
b->buf = newBuf;
b->space = newLen;
}
return SECSuccess;
}
SECStatus
sslBuffer_Append(sslBuffer *b, const void *data, unsigned int len)
{
SECStatus rv = sslBuffer_Grow(b, b->len + len);
if (rv != SECSuccess) {
return SECFailure; /* Code already set. */
}
if (len > 0) {
PORT_Assert(data);
PORT_Memcpy(SSL_BUFFER_NEXT(b), data, len);
}
b->len += len;
return SECSuccess;
}
SECStatus
sslBuffer_AppendNumber(sslBuffer *b, PRUint64 v, unsigned int size)
{
SECStatus rv = sslBuffer_Grow(b, b->len + size);
if (rv != SECSuccess) {
return SECFailure;
}
ssl_EncodeUintX(SSL_BUFFER_NEXT(b), v, size);
b->len += size;
return SECSuccess;
}
SECStatus
sslBuffer_AppendVariable(sslBuffer *b, const PRUint8 *data, unsigned int len,
unsigned int size)
{
PORT_Assert(size <= 4 && size > 0);
PORT_Assert(b);
if (len >= (1ULL << (8 * size))) {
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
return SECFailure;
}
if (sslBuffer_Grow(b, b->len + len + size) != SECSuccess) {
return SECFailure;
}
ssl_EncodeUintX(SSL_BUFFER_NEXT(b), len, size);
b->len += size;
if (len != 0) {
PORT_Assert(data);
/* We sometimes pass NULL, 0 and memcpy() doesn't want NULL. */
PORT_Memcpy(SSL_BUFFER_NEXT(b), data, len);
}
b->len += len;
return SECSuccess;
}
SECStatus
sslBuffer_AppendBuffer(sslBuffer *b, const sslBuffer *append)
{
return sslBuffer_Append(b, append->buf, append->len);
}
SECStatus
sslBuffer_AppendBufferVariable(sslBuffer *b, const sslBuffer *append,
unsigned int size)
{
return sslBuffer_AppendVariable(b, append->buf, append->len, size);
}
SECStatus
sslBuffer_Skip(sslBuffer *b, unsigned int size, unsigned int *savedOffset)
{
if (sslBuffer_Grow(b, b->len + size) != SECSuccess) {
return SECFailure;
}
if (savedOffset) {
*savedOffset = b->len;
}
b->len += size;
return SECSuccess;
}
/* A common problem is that a buffer is used to construct a variable length
* structure of unknown length. The length field for that structure is then
* populated afterwards. This function makes this process a little easier.
*
* To use this, before encoding the variable length structure, skip the spot
* where the length would be using sslBuffer_Skip(). After encoding the
* structure, and before encoding anything else, call this function passing the
* value returned from sslBuffer_Skip() as |at| to have the length inserted.
*/
SECStatus
sslBuffer_InsertLength(sslBuffer *b, unsigned int at, unsigned int size)
{
unsigned int len;
PORT_Assert(b->len >= at + size);
PORT_Assert(b->space >= at + size);
len = b->len - (at + size);
PORT_Assert(size <= 4 && size > 0);
if (len >= (1ULL << (8 * size))) {
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
return SECFailure;
}
ssl_EncodeUintX(SSL_BUFFER_BASE(b) + at, len, size);
return SECSuccess;
}
SECStatus
sslBuffer_InsertNumber(sslBuffer *b, unsigned int at,
PRUint64 v, unsigned int size)
{
PORT_Assert(b->len >= at + size);
PORT_Assert(b->space >= at + size);
PORT_Assert(size <= 4 && size > 0);
if (v >= (1ULL << (8 * size))) {
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
return SECFailure;
}
ssl_EncodeUintX(SSL_BUFFER_BASE(b) + at, v, size);
return SECSuccess;
}
void
sslBuffer_Clear(sslBuffer *b)
{
if (!b->fixed) {
if (b->buf) {
PORT_Free(b->buf);
b->buf = NULL;
}
b->space = 0;
}
b->len = 0;
}
SECStatus
sslRead_Read(sslReader *reader, unsigned int count, sslReadBuffer *out)
{
if (!reader || !out) {
PORT_SetError(SEC_ERROR_INVALID_ARGS);
return SECFailure;
}
if (reader->buf.len < reader->offset ||
count > SSL_READER_REMAINING(reader)) {
PORT_SetError(SEC_ERROR_BAD_DATA);
return SECFailure;
}
out->buf = SSL_READER_CURRENT(reader);
out->len = count;
reader->offset += count;
return SECSuccess;
}
SECStatus
sslRead_ReadVariable(sslReader *reader, unsigned int sizeLen, sslReadBuffer *out)
{
PRUint64 variableLen = 0;
SECStatus rv = sslRead_ReadNumber(reader, sizeLen, &variableLen);
if (rv != SECSuccess) {
PORT_SetError(SEC_ERROR_BAD_DATA);
return SECFailure;
}
if (!variableLen) {
// It is ok to have an empty variable.
out->len = variableLen;
return SECSuccess;
}
return sslRead_Read(reader, variableLen, out);
}
SECStatus
sslRead_ReadNumber(sslReader *reader, unsigned int bytes, PRUint64 *num)
{
if (!reader || !num) {
PORT_SetError(SEC_ERROR_INVALID_ARGS);
return SECFailure;
}
if (reader->buf.len < reader->offset ||
bytes > SSL_READER_REMAINING(reader) ||
bytes > 8) {
PORT_SetError(SEC_ERROR_BAD_DATA);
return SECFailure;
}
unsigned int i;
PRUint64 number = 0;
for (i = 0; i < bytes; i++) {
number = (number << 8) + reader->buf.buf[i + reader->offset];
}
reader->offset = reader->offset + bytes;
*num = number;
return SECSuccess;
}
/**************************************************************************
* Append Handshake functions.
* All these functions set appropriate error codes.
* Most rely on ssl3_AppendHandshake to set the error code.
**************************************************************************/
#define MAX_SEND_BUF_LENGTH 32000 /* watch for 16-bit integer overflow */
#define MIN_SEND_BUF_LENGTH 4000
static SECStatus
ssl3_AppendHandshakeInternal(sslSocket *ss, const void *void_src, unsigned int bytes, PRBool suppressHash)
{
unsigned char *src = (unsigned char *)void_src;
int room = ss->sec.ci.sendBuf.space - ss->sec.ci.sendBuf.len;
SECStatus rv;
PORT_Assert(ss->opt.noLocks || ssl_HaveSSL3HandshakeLock(ss)); /* protects sendBuf. */
if (!bytes)
return SECSuccess;
if (ss->sec.ci.sendBuf.space < MAX_SEND_BUF_LENGTH && room < bytes) {
rv = sslBuffer_Grow(&ss->sec.ci.sendBuf, PR_MAX(MIN_SEND_BUF_LENGTH,
PR_MIN(MAX_SEND_BUF_LENGTH, ss->sec.ci.sendBuf.len + bytes)));
if (rv != SECSuccess)
return SECFailure; /* sslBuffer_Grow sets a memory error code. */
room = ss->sec.ci.sendBuf.space - ss->sec.ci.sendBuf.len;
}
PRINT_BUF(60, (ss, "Append to Handshake", (unsigned char *)void_src, bytes));
// TODO: Move firstHsDone and version check into callers as a suppression.
if (!suppressHash && (!ss->firstHsDone || ss->version < SSL_LIBRARY_VERSION_TLS_1_3)) {
rv = ssl3_UpdateHandshakeHashes(ss, src, bytes);
if (rv != SECSuccess)
return SECFailure; /* error code set by ssl3_UpdateHandshakeHashes */
}
while (bytes > room) {
if (room > 0)
PORT_Memcpy(ss->sec.ci.sendBuf.buf + ss->sec.ci.sendBuf.len, src,
room);
ss->sec.ci.sendBuf.len += room;
rv = ssl3_FlushHandshake(ss, ssl_SEND_FLAG_FORCE_INTO_BUFFER);
if (rv != SECSuccess) {
return SECFailure; /* error code set by ssl3_FlushHandshake */
}
bytes -= room;
src += room;
room = ss->sec.ci.sendBuf.space;
PORT_Assert(ss->sec.ci.sendBuf.len == 0);
}
PORT_Memcpy(ss->sec.ci.sendBuf.buf + ss->sec.ci.sendBuf.len, src, bytes);
ss->sec.ci.sendBuf.len += bytes;
return SECSuccess;
}
SECStatus
ssl3_AppendHandshakeSuppressHash(sslSocket *ss, const void *void_src, unsigned int bytes)
{
return ssl3_AppendHandshakeInternal(ss, void_src, bytes, PR_TRUE);
}
SECStatus
ssl3_AppendHandshake(sslSocket *ss, const void *void_src, unsigned int bytes)
{
return ssl3_AppendHandshakeInternal(ss, void_src, bytes, PR_FALSE);
}
SECStatus
ssl3_AppendHandshakeNumber(sslSocket *ss, PRUint64 num, unsigned int lenSize)
{
PRUint8 b[sizeof(num)];
SSL_TRC(60, ("%d: number:", SSL_GETPID()));
ssl_EncodeUintX(b, num, lenSize);
return ssl3_AppendHandshake(ss, b, lenSize);
}
SECStatus
ssl3_AppendHandshakeVariable(sslSocket *ss, const PRUint8 *src,
unsigned int bytes, unsigned int lenSize)
{
SECStatus rv;
PORT_Assert((bytes < (1 << 8) && lenSize == 1) ||
(bytes < (1L << 16) && lenSize == 2) ||
(bytes < (1L << 24) && lenSize == 3));
SSL_TRC(60, ("%d: append variable:", SSL_GETPID()));
rv = ssl3_AppendHandshakeNumber(ss, bytes, lenSize);
if (rv != SECSuccess) {
return SECFailure; /* error code set by AppendHandshake. */
}
SSL_TRC(60, ("data:"));
return ssl3_AppendHandshake(ss, src, bytes);
}
SECStatus
ssl3_AppendBufferToHandshake(sslSocket *ss, sslBuffer *buf)
{
return ssl3_AppendHandshake(ss, buf->buf, buf->len);
}
SECStatus
ssl3_AppendBufferToHandshakeVariable(sslSocket *ss, sslBuffer *buf,
unsigned int lenSize)
{
return ssl3_AppendHandshakeVariable(ss, buf->buf, buf->len, lenSize);
}