1 files changed, 302 insertions, 0 deletions
diff --git a/src/protocol/internal/fqterm_ssh_buffer.cpp b/src/protocol/internal/fqterm_ssh_buffer.cpp
new file mode 100644
index 0000000..d95497a
--- /dev/null
+++ b/src/protocol/internal/fqterm_ssh_buffer.cpp
@@ -0,0 +1,302 @@
+/***************************************************************************
+ *   fqterm, a terminal emulator for both BBS and *nix.                    *
+ *   Copyright (C) 2008 fqterm development group.                          *
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ *   This program is distributed in the hope that it will be useful,       *
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
+ *   GNU General Public License for more details.                          *
+ *                                                                         *
+ *   You should have received a copy of the GNU General Public License     *
+ *   along with this program; if not, write to the                         *
+ *   Free Software Foundation, Inc.,                                       *
+ *   51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.               *
+ ***************************************************************************/
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <vector>
+
+#include "fqterm_trace.h"
+#include "fqterm_ssh_buffer.h"
+#include "fqterm_serialization.h"
+
+namespace FQTerm {
+//==============================================================================
+// FQTermSSHBuffer
+//==============================================================================
+
+FQTermSSHBuffer::FQTermSSHBuffer(int size) {
+  alloc_size_ = size;
+  buffer_size_ = 0;
+  offset_ = 0;
+  buffer_ = new u_char[alloc_size_];
+}
+
+FQTermSSHBuffer::~FQTermSSHBuffer() {
+  delete [] buffer_;
+  offset_ = 0;
+  buffer_size_ = 0;
+  alloc_size_ = 0;
+}
+
+void FQTermSSHBuffer::ensure(int len) {
+  if (len <= (alloc_size_ - (offset_ + buffer_size_))) {
+    return ;
+  } else {
+    alloc_size_ = buffer_size_ + len;
+    rebuffer();
+  }
+}
+
+void FQTermSSHBuffer::rebuffer() {
+  u_char *newBuffer;
+  newBuffer = new u_char[alloc_size_];
+  memset(newBuffer, 0, alloc_size_);
+  memcpy(newBuffer, buffer_ + offset_, buffer_size_);
+  delete [] buffer_;
+  buffer_ = newBuffer;
+  offset_ = 0;
+}
+
+void FQTermSSHBuffer::clear() {
+  memset(buffer_, 0, alloc_size_);
+  offset_ = 0;
+  buffer_size_ = 0;
+}
+
+void FQTermSSHBuffer::consume(int len) {
+  if (len > buffer_size_) {
+    len = buffer_size_;
+  } 
+  
+  offset_ += len;
+  buffer_size_ -= len;
+}
+
+void FQTermSSHBuffer::putRawData(const char *data, int len) {
+  if (len < 0) {
+    FQ_TRACE("sshbuffer", 0) << "Write data error.";
+  }
+
+  ensure(len);
+  memcpy((buffer_ + offset_ + buffer_size_), data, len);
+  buffer_size_ += len;
+}
+
+void FQTermSSHBuffer::getRawData(char *data, int len) {
+  if (len <= buffer_size_ && len >= 0) {
+    memcpy(data, buffer_ + offset_, len);
+    consume(len);
+  } else {
+    FQ_TRACE("sshbuffer", 0) << "Read too many data: " << len << " bytes.";
+  } 
+}
+
+//==============================================================================
+// Store an BIGNUM in the buffer with a 2-byte msb first bit count, followed by
+// (bits+7)/8 bytes of binary data, msb first.
+//==============================================================================
+
+void FQTermSSHBuffer::putSSH1BN(BIGNUM *bignum) {
+  int bits = BN_num_bits(bignum);
+  int bin_size = (bits + 7) / 8;
+  u_char *buf = new u_char[bin_size];
+  int oi;
+  u_char msg[2];
+
+  // Get the value of in binary
+  oi = BN_bn2bin(bignum, buf);
+  if (oi != bin_size) {
+    FQ_TRACE("sshbuffer", 0) << "BN_bn2bin() failed: oi = " << oi
+                             << " != bin_size." << bin_size;
+  } 
+
+  // Store the number of bits in the buffer in two bytes, msb first
+  htonu16(msg, bits);
+  putRawData((char*)msg, 2);
+  // Store the binary data.
+  putRawData((char*)buf, oi);
+
+  memset(buf, 0, bin_size);
+  delete [] buf;
+}
+
+
+
+void FQTermSSHBuffer::putSSH2BN(BIGNUM *bignum) {
+  // FIXME: support negative number and add error handling.
+
+  FQ_VERIFY(!bignum->neg);  // currently we don't support negative big number.
+
+  if (BN_is_zero(bignum)) {
+    this->putInt(0);
+  } else {
+    u_int bytes = BN_num_bytes(bignum) + 1;
+
+    FQ_VERIFY(bytes >= 2); // currently we don't support big numbers so small
+
+    std::vector<u_char> buf(bytes);
+    buf[0] = 0;
+
+    int bin_len = BN_bn2bin(bignum, &buf[0] + 1);
+
+    FQ_VERIFY(bin_len == (int)bytes - 1);
+      
+    u_int no_high_bit = (buf[1] & 0x80) ? 0 : 1;
+
+    this->putInt(bytes - no_high_bit);
+    this->putRawData((const char *)&buf[0] + no_high_bit, bytes - no_high_bit);
+  }
+}
+
+//==============================================================================
+// Retrieves a BIGNUM from the buffer.
+//==============================================================================
+
+void FQTermSSHBuffer::getSSH1BN(BIGNUM *bignum) {
+  int bits, bytes;
+  u_char buf[2];
+  u_char *bin;
+
+  // Get the number for bits.
+  getRawData((char*)buf, 2);
+  bits = ntohu16(buf);
+  // Compute the number of binary bytes that follow.
+  bytes = (bits + 7) / 8;
+  if (bytes > 8 *1024) {
+    FQ_TRACE("sshbuffer", 0) << "Can't handle BN of size " << bytes;
+    return ;
+  }
+  if (len() < bytes) {
+    FQ_TRACE("sshbuffer", 0) << "The input buffer is too small.";
+    return ;
+  }
+  bin = data();
+  BN_bin2bn(bin, bytes, bignum);
+  consume(bytes);
+}
+
+void FQTermSSHBuffer::getSSH2BN(BIGNUM *bignum) {
+  // FIXME: support negative numbers and error handling
+  int len;
+  unsigned char *hex_data = (unsigned char *)getString(&len);
+
+  FQ_VERIFY(!(len > 0 && (hex_data[0] & 0x80)));  // don't support negative numbers.
+
+  FQ_VERIFY(len < 10240);  // don't support so large numbers.
+
+  BIGNUM *res = BN_bin2bn(hex_data, len, bignum);
+
+  FQ_VERIFY(res != NULL);
+
+  delete hex_data;
+}
+
+u_short FQTermSSHBuffer::getWord() {
+  u_char buf[2];
+  u_short data;
+
+  getRawData((char*)buf, 2);
+  data = ntohu16(buf);
+  return data;
+}
+
+void FQTermSSHBuffer::putWord(u_short data) {
+  u_char buf[2];
+
+  htonu16(buf, data);
+  putRawData((char*)buf, 2);
+}
+
+u_int FQTermSSHBuffer::getInt() {
+  u_char buf[4];
+  u_int data;
+  getRawData((char*)buf, 4);
+  data = ntohu32(buf);
+  return data;
+}
+
+void FQTermSSHBuffer::putInt(u_int data) {
+  u_char buf[4];
+
+  htonu32(buf, data);
+  putRawData((char*)buf, 4);
+}
+
+//==============================================================================
+// Return a character from the buffer (0-255).
+//==============================================================================
+
+u_char FQTermSSHBuffer::getByte() {
+  u_char ch;
+
+  getRawData((char*) &ch, 1);
+  return ch;
+}
+
+//==============================================================================
+// Stores a character in the buffer.
+//==============================================================================
+
+void FQTermSSHBuffer::putByte(int data) {
+  u_char ch = data;
+
+  putRawData((char*) &ch, 1);
+}
+
+//==============================================================================
+// Stores an arbitrary binary string in the buffer.
+//==============================================================================
+
+void FQTermSSHBuffer::putString(const char *str, int len) {
+  if (str == NULL) {
+    FQ_TRACE("sshbuffer", 0) << "Can't put a null pointer string.";
+    return ;
+  }
+
+  if (len < 0) {
+    len = strlen(str);
+  }
+
+  putInt(len);
+  putRawData(str, len);
+}
+
+//==============================================================================
+// Return an arbitrary binary string from the buffer. The string cannot be 
+// longer than 256k. The returned value points to memory allocated with new;
+// It is the responsibility of the calling function to free the data. 
+//==============================================================================
+
+void *FQTermSSHBuffer::getString(int *length) {
+  u_char *data;
+  u_int len;
+
+  // Get the length.
+  len = getInt();
+  if ((long)len > buffer_size_) {
+    FQ_TRACE("sshbuffer", 0)
+        << "String length " << len
+        << " is greater than buffer size " << buffer_size_;
+    return 0;
+  }
+  // Allocate space for the string. Add one byte for a null character.
+  data = new u_char[len + 1];
+  // Get the string.
+  getRawData((char*)data, len);
+  // Append a null character to make processing easier.
+  data[len] = 0;
+  if (length != NULL) {
+    *length = len;
+  } 
+  // return the length of the string.
+  return data;
+}
+
+}  // namespace FQTerm