File indexing completed on 2024-12-01 10:31:54

 /*
  * Copyright (C) 2003-2007  Justin Karneges <justin@affinix.com>
  * Copyright (C) 2004,2005  Brad Hards <bradh@frogmouth.net>
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either
  * version 2.1 of the License, or (at your option) any later version.
  *
  * This library 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
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
  * License along with this library; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  * 02110-1301  USA
  *
  */
 
 #include "qca_tools.h"
 
 #include "qdebug.h"
 
 #ifdef Q_OS_UNIX
 #include <cstdlib>
 #include <sys/mman.h>
 #endif
 #include "botantools/botantools.h"
 
 namespace QCA {
 
 static bool can_lock()
 {
 #ifdef Q_OS_UNIX
     bool ok = false;
 #ifdef MLOCK_NOT_VOID_PTR
 #define MLOCK_TYPE char *
 #define MLOCK_TYPE_CAST (MLOCK_TYPE)
 #else
 #define MLOCK_TYPE void *
 #define MLOCK_TYPE_CAST
 #endif
 
     MLOCK_TYPE d = MLOCK_TYPE_CAST malloc(256);
     if (mlock(d, 256) == 0) {
         munlock(d, 256);
         ok = true;
     }
     free(d);
     return ok;
 #else
     return true;
 #endif
 }
 
 // Botan shouldn't throw any exceptions in our init/deinit.
 
 static Botan::Allocator *alloc = nullptr;
 
 void botan_throw_abort()
 {
     fprintf(stderr, "QCA: Exception from internal Botan\n");
     abort();
 }
 
 bool botan_init(int prealloc, bool mmap)
 {
     // 64k minimum
     if (prealloc < 64)
         prealloc = 64;
 
     bool secmem = false;
 
     try {
         Botan::Builtin_Modules modules;
         Botan::Library_State  *libstate = new Botan::Library_State(modules.mutex_factory());
         libstate->prealloc_size         = prealloc * 1024;
         Botan::set_global_state(libstate);
         Botan::global_state().load(modules);
 
         if (can_lock()) {
             Botan::global_state().set_default_allocator("locking");
             secmem = true;
         } else if (mmap) {
             Botan::global_state().set_default_allocator("mmap");
             secmem = true;
         }
         alloc = Botan::Allocator::get(true);
     } catch (std::exception &) {
         fprintf(stderr, "QCA: Error initializing internal Botan\n");
         abort();
     }
 
     return secmem;
 }
 
 void botan_deinit()
 {
     try {
         alloc = nullptr;
         Botan::set_global_state(nullptr);
     } catch (std::exception &) {
         botan_throw_abort();
     }
 }
 
 void *botan_secure_alloc(int bytes)
 {
     try {
         return alloc->allocate((Botan::u32bit)bytes);
     } catch (std::exception &) {
         botan_throw_abort();
     }
     return nullptr; // never get here
 }
 
 void botan_secure_free(void *p, int bytes)
 {
     try {
         alloc->deallocate(p, (Botan::u32bit)bytes);
     } catch (std::exception &) {
         botan_throw_abort();
     }
 }
 
 } // end namespace QCA
 
 void *qca_secure_alloc(int bytes)
 {
     // allocate enough room to store a size value in front, return a pointer after it
     char *c                       = (char *)QCA::botan_secure_alloc(bytes + sizeof(int));
     reinterpret_cast<int *>(c)[0] = bytes + sizeof(int);
     return c + sizeof(int);
 }
 
 void qca_secure_free(void *p)
 {
     // backtrack to read the size value
     char *c = (char *)p;
     c -= sizeof(int);
     const int bytes = reinterpret_cast<int *>(c)[0];
     QCA::botan_secure_free(c, bytes);
 }
 
 void *qca_secure_realloc(void *p, int bytes)
 {
     // if null, do a plain alloc (just like how realloc() works)
     if (!p)
         return qca_secure_alloc(bytes);
 
     // backtrack to read the size value
     char *c = (char *)p;
     c -= sizeof(int);
     const int oldsize = reinterpret_cast<int *>(c)[0] - sizeof(int);
 
     // alloc the new chunk
     char *new_p = (char *)qca_secure_alloc(bytes);
     if (!new_p)
         return nullptr;
 
     // move over the memory from the original block
     memmove(new_p, p, qMin(oldsize, bytes));
 
     // free the original
     qca_secure_free(p);
 
     // done
     return new_p;
 }
 
 namespace QCA {
 
 // secure or non-secure buffer, with trailing 0-byte.
 // buffer size of 0 is okay (sbuf/qbuf will be 0).
 struct alloc_info
 {
     bool  sec;
     char *data;
     int   size;
 
     // internal
     Botan::SecureVector<Botan::byte> *sbuf;
     QByteArray                       *qbuf;
 };
 
 // note: these functions don't return error if memory allocation/resizing
 //   fails..  maybe fix this someday?
 
 // ai: uninitialized
 // size: >= 0
 // note: memory will be initially zero'd out
 static bool ai_new(alloc_info *ai, int size, bool sec);
 
 // ai: uninitialized
 // from: initialized
 static bool ai_copy(alloc_info *ai, const alloc_info *from);
 
 // ai: initialized
 // new_size: >= 0
 static bool ai_resize(alloc_info *ai, int new_size);
 
 // ai: initialized
 static void ai_delete(alloc_info *ai);
 
 bool ai_new(alloc_info *ai, int size, bool sec)
 {
     if (size < 0)
         return false;
 
     ai->size = size;
     ai->sec  = sec;
 
     if (size == 0) {
         ai->sbuf = nullptr;
         ai->qbuf = nullptr;
         ai->data = nullptr;
         return true;
     }
 
     if (sec) {
         try {
             ai->sbuf = new Botan::SecureVector<Botan::byte>((Botan::u32bit)size + 1);
         } catch (std::exception &) {
             botan_throw_abort();
             return false; // never get here
         }
 
         (*(ai->sbuf))[size] = 0;
         ai->qbuf            = nullptr;
         Botan::byte *bp     = (Botan::byte *)(*(ai->sbuf));
         ai->data            = (char *)bp;
     } else {
         ai->sbuf = nullptr;
         ai->qbuf = new QByteArray(size, 0);
         ai->data = ai->qbuf->data();
     }
 
     return true;
 }
 
 bool ai_copy(alloc_info *ai, const alloc_info *from)
 {
     ai->size = from->size;
     ai->sec  = from->sec;
 
     if (ai->size == 0) {
         ai->sbuf = nullptr;
         ai->qbuf = nullptr;
         ai->data = nullptr;
         return true;
     }
 
     if (ai->sec) {
         try {
             ai->sbuf = new Botan::SecureVector<Botan::byte>(*(from->sbuf));
         } catch (std::exception &) {
             botan_throw_abort();
             return false; // never get here
         }
 
         ai->qbuf        = nullptr;
         Botan::byte *bp = (Botan::byte *)(*(ai->sbuf));
         ai->data        = (char *)bp;
     } else {
         ai->sbuf = nullptr;
         ai->qbuf = new QByteArray(*(from->qbuf));
         ai->data = ai->qbuf->data();
     }
 
     return true;
 }
 
 bool ai_resize(alloc_info *ai, int new_size)
 {
     if (new_size < 0)
         return false;
 
     // new size is empty
     if (new_size == 0) {
         // we currently aren't empty
         if (ai->size > 0) {
             if (ai->sec) {
                 delete ai->sbuf;
                 ai->sbuf = nullptr;
             } else {
                 delete ai->qbuf;
                 ai->qbuf = nullptr;
             }
 
             ai->size = 0;
             ai->data = nullptr;
         }
 
         return true;
     }
 
     if (ai->sec) {
         Botan::SecureVector<Botan::byte> *new_buf;
         try {
             new_buf = new Botan::SecureVector<Botan::byte>((Botan::u32bit)new_size + 1);
         } catch (std::exception &) {
             botan_throw_abort();
             return false; // never get here
         }
 
         Botan::byte *new_p = (Botan::byte *)(*new_buf);
         if (ai->size > 0) {
             const Botan::byte *old_p = (const Botan::byte *)(*(ai->sbuf));
             memcpy(new_p, old_p, qMin(new_size, ai->size));
             delete ai->sbuf;
         }
         ai->sbuf                = new_buf;
         ai->size                = new_size;
         (*(ai->sbuf))[new_size] = 0;
         ai->data                = (char *)new_p;
     } else {
         if (ai->size > 0)
             ai->qbuf->resize(new_size);
         else
             ai->qbuf = new QByteArray(new_size, 0);
 
         ai->size = new_size;
         ai->data = ai->qbuf->data();
     }
 
     return true;
 }
 
 void ai_delete(alloc_info *ai)
 {
     if (ai->size > 0) {
         if (ai->sec)
             delete ai->sbuf;
         else
             delete ai->qbuf;
     }
 }
 
 //----------------------------------------------------------------------------
 // MemoryRegion
 //----------------------------------------------------------------------------
 static char blank[] = "";
 
 class MemoryRegion::Private : public QSharedData
 {
 public:
     alloc_info ai;
 
     Private(int size, bool sec)
     {
         ai_new(&ai, size, sec);
     }
 
     Private(const QByteArray &from, bool sec)
     {
         ai_new(&ai, from.size(), sec);
         memcpy(ai.data, from.data(), ai.size);
     }
 
     Private(const Private &from)
         : QSharedData(from)
     {
         ai_copy(&ai, &from.ai);
     }
 
     ~Private()
     {
         ai_delete(&ai);
     }
 
     bool resize(int new_size)
     {
         return ai_resize(&ai, new_size);
     }
 
     void setSecure(bool sec)
     {
         // if same mode, do nothing
         if (ai.sec == sec)
             return;
 
         alloc_info other;
         ai_new(&other, ai.size, sec);
         memcpy(other.data, ai.data, ai.size);
         ai_delete(&ai);
         ai = other;
     }
 };
 
 MemoryRegion::MemoryRegion()
     : _secure(false)
     , d(nullptr)
 {
 }
 
 MemoryRegion::MemoryRegion(const char *str)
     : _secure(false)
     , d(new Private(QByteArray::fromRawData(str, strlen(str)), false))
 {
 }
 
 MemoryRegion::MemoryRegion(const QByteArray &from)
     : _secure(false)
     , d(new Private(from, false))
 {
 }
 
 MemoryRegion::MemoryRegion(const MemoryRegion &from)
     : _secure(from._secure)
     , d(from.d)
 {
 }
 
 MemoryRegion::~MemoryRegion()
 {
 }
 
 MemoryRegion &MemoryRegion::operator=(const MemoryRegion &from)
 {
     _secure = from._secure;
     d       = from.d;
     return *this;
 }
 
 MemoryRegion &MemoryRegion::operator=(const QByteArray &from)
 {
     set(from, false);
     return *this;
 }
 
 bool MemoryRegion::isNull() const
 {
     return (d ? false : true);
 }
 
 bool MemoryRegion::isSecure() const
 {
     return _secure;
 }
 
 QByteArray MemoryRegion::toByteArray() const
 {
     if (!d)
         return QByteArray();
 
     if (d->ai.sec) {
         QByteArray buf(d->ai.size, 0);
         memcpy(buf.data(), d->ai.data, d->ai.size);
         return buf;
     } else {
         if (d->ai.size > 0)
             return *(d->ai.qbuf);
         else
             return QByteArray((int)0, (char)0);
     }
 }
 
 MemoryRegion::MemoryRegion(bool secure)
     : _secure(secure)
     , d(nullptr)
 {
 }
 
 MemoryRegion::MemoryRegion(int size, bool secure)
     : _secure(secure)
     , d(new Private(size, secure))
 {
 }
 
 MemoryRegion::MemoryRegion(const QByteArray &from, bool secure)
     : _secure(secure)
     , d(new Private(from, secure))
 {
 }
 
 char *MemoryRegion::data()
 {
     if (!d)
         return blank;
     return d->ai.data;
 }
 
 const char *MemoryRegion::data() const
 {
     if (!d)
         return blank;
     return d->ai.data;
 }
 
 const char *MemoryRegion::constData() const
 {
     if (!d)
         return blank;
     return d->ai.data;
 }
 
 char &MemoryRegion::at(int index)
 {
     return *(d->ai.data + index);
 }
 
 const char &MemoryRegion::at(int index) const
 {
     return *(d->ai.data + index);
 }
 
 int MemoryRegion::size() const
 {
     if (!d)
         return 0;
     return d->ai.size;
 }
 
 bool MemoryRegion::isEmpty() const
 {
     if (!d)
         return true;
     return (d->ai.size > 0 ? false : true);
 }
 
 bool MemoryRegion::resize(int size)
 {
     if (!d) {
         d = new Private(size, _secure);
         return true;
     }
 
     if (d->ai.size == size)
         return true;
 
     return d->resize(size);
 }
 
 void MemoryRegion::set(const QByteArray &from, bool secure)
 {
     _secure = secure;
 
     if (!from.isEmpty())
         d = new Private(from, secure);
     else
         d = new Private(0, secure);
 }
 
 void MemoryRegion::setSecure(bool secure)
 {
     _secure = secure;
 
     if (!d) {
         d = new Private(0, secure);
         return;
     }
 
     d->setSecure(secure);
 }
 
 //----------------------------------------------------------------------------
 // SecureArray
 //----------------------------------------------------------------------------
 SecureArray::SecureArray()
     : MemoryRegion(true)
 {
 }
 
 SecureArray::SecureArray(int size, char ch)
     : MemoryRegion(size, true)
 {
     // ai_new fills with zeros for us
     if (ch != 0)
         fill(ch, size);
 }
 
 SecureArray::SecureArray(const char *str)
     : MemoryRegion(QByteArray::fromRawData(str, strlen(str)), true)
 {
 }
 
 SecureArray::SecureArray(const QByteArray &a)
     : MemoryRegion(a, true)
 {
 }
 
 SecureArray::SecureArray(const MemoryRegion &a)
     : MemoryRegion(a)
 {
     setSecure(true);
 }
 
 SecureArray::SecureArray(const SecureArray &from)
     : MemoryRegion(from)
 {
 }
 
 SecureArray::~SecureArray()
 {
 }
 
 SecureArray &SecureArray::operator=(const SecureArray &from)
 {
     MemoryRegion::operator=(from);
     return *this;
 }
 
 SecureArray &SecureArray::operator=(const QByteArray &from)
 {
     MemoryRegion::set(from, true);
     return *this;
 }
 
 void SecureArray::clear()
 {
     MemoryRegion::resize(0);
 }
 
 bool SecureArray::resize(int size)
 {
     return MemoryRegion::resize(size);
 }
 
 char &SecureArray::operator[](int index)
 {
     return at(index);
 }
 
 const char &SecureArray::operator[](int index) const
 {
     return at(index);
 }
 
 char &SecureArray::at(int index)
 {
     return MemoryRegion::at(index);
 }
 
 const char &SecureArray::at(int index) const
 {
     return MemoryRegion::at(index);
 }
 
 char *SecureArray::data()
 {
     return MemoryRegion::data();
 }
 
 const char *SecureArray::data() const
 {
     return MemoryRegion::data();
 }
 
 const char *SecureArray::constData() const
 {
     return MemoryRegion::constData();
 }
 
 int SecureArray::size() const
 {
     return MemoryRegion::size();
 }
 
 bool SecureArray::isEmpty() const
 {
     return MemoryRegion::isEmpty();
 }
 
 QByteArray SecureArray::toByteArray() const
 {
     return MemoryRegion::toByteArray();
 }
 
 SecureArray &SecureArray::append(const SecureArray &a)
 {
     const int oldsize = size();
     resize(oldsize + a.size());
     memcpy(data() + oldsize, a.data(), a.size());
     return *this;
 }
 
 bool SecureArray::operator==(const MemoryRegion &other) const
 {
     if (this == &other)
         return true;
     if (size() == other.size() && memcmp(data(), other.data(), size()) == 0)
         return true;
     return false;
 }
 
 SecureArray &SecureArray::operator+=(const SecureArray &a)
 {
     return append(a);
 }
 
 void SecureArray::fill(char fillChar, int fillToPosition)
 {
     const int len = (fillToPosition == -1) ? size() : qMin(fillToPosition, size());
     if (len > 0)
         memset(data(), (int)fillChar, len);
 }
 
 void SecureArray::set(const SecureArray &from)
 {
     *this = from;
 }
 
 void SecureArray::set(const QByteArray &from)
 {
     *this = from;
 }
 
 const SecureArray operator+(const SecureArray &a, const SecureArray &b)
 {
     SecureArray c = a;
     return c.append(b);
 }
 
 //----------------------------------------------------------------------------
 // BigInteger
 //----------------------------------------------------------------------------
 static void negate_binary(char *a, int size)
 {
     // negate = two's compliment + 1
     bool done = false;
     for (int n = size - 1; n >= 0; --n) {
         a[n] = ~a[n];
         if (!done) {
             if ((unsigned char)a[n] < 0xff) {
                 ++a[n];
                 done = true;
             } else
                 a[n] = 0;
         }
     }
 }
 
 class BigInteger::Private : public QSharedData
 {
 public:
     Botan::BigInt n;
 };
 
 BigInteger::BigInteger()
 {
     d = new Private;
 }
 
 BigInteger::BigInteger(int i)
 {
     d = new Private;
     if (i < 0) {
         d->n = Botan::BigInt(i * (-1));
         d->n.set_sign(Botan::BigInt::Negative);
     } else {
         d->n = Botan::BigInt(i);
         d->n.set_sign(Botan::BigInt::Positive);
     }
 }
 
 BigInteger::BigInteger(const char *c)
 {
     d = new Private;
     fromString(QString::fromLatin1(c));
 }
 
 BigInteger::BigInteger(const QString &s)
 {
     d = new Private;
     fromString(s);
 }
 
 BigInteger::BigInteger(const SecureArray &a)
 {
     d = new Private;
     fromArray(a);
 }
 
 BigInteger::BigInteger(const BigInteger &from)
 {
     *this = from;
 }
 
 BigInteger::~BigInteger()
 {
 }
 
 BigInteger &BigInteger::operator=(const BigInteger &from)
 {
     d = from.d;
     return *this;
 }
 
 BigInteger &BigInteger::operator+=(const BigInteger &i)
 {
     d->n += i.d->n;
     return *this;
 }
 
 BigInteger &BigInteger::operator-=(const BigInteger &i)
 {
     d->n -= i.d->n;
     return *this;
 }
 
 BigInteger &BigInteger::operator*=(const BigInteger &i)
 {
     d->n *= i.d->n;
     return *this;
 }
 
 BigInteger &BigInteger::operator/=(const BigInteger &i)
 {
     try {
         d->n /= i.d->n;
     } catch (std::exception &) {
         fprintf(stderr, "QCA: Botan integer division error\n");
         abort();
     }
     return *this;
 }
 
 BigInteger &BigInteger::operator%=(const BigInteger &i)
 {
     try {
         d->n %= i.d->n;
     } catch (std::exception &) {
         fprintf(stderr, "QCA: Botan integer division error\n");
         abort();
     }
     return *this;
 }
 
 BigInteger &BigInteger::operator=(const QString &s)
 {
     fromString(s);
     return *this;
 }
 
 int BigInteger::compare(const BigInteger &n) const
 {
     return ((d->n).cmp(n.d->n, true));
 }
 
 QTextStream &operator<<(QTextStream &stream, const BigInteger &b)
 {
     stream << b.toString();
     return stream;
 }
 
 SecureArray BigInteger::toArray() const
 {
     int size = d->n.encoded_size(Botan::BigInt::Binary);
 
     // return at least 8 bits
     if (size == 0) {
         SecureArray a(1);
         a[0] = 0;
         return a;
     }
 
     int         offset = 0;
     SecureArray a;
 
     // make room for a sign bit if needed
     if (d->n.get_bit((size * 8) - 1)) {
         ++size;
         a.resize(size);
         a[0] = 0;
         ++offset;
     } else
         a.resize(size);
 
     Botan::BigInt::encode((Botan::byte *)a.data() + offset, d->n, Botan::BigInt::Binary);
 
     if (d->n.is_negative())
         negate_binary(a.data(), a.size());
 
     return a;
 }
 
 void BigInteger::fromArray(const SecureArray &_a)
 {
     if (_a.isEmpty()) {
         d->n = Botan::BigInt(0);
         return;
     }
     SecureArray a = _a;
 
     Botan::BigInt::Sign sign = Botan::BigInt::Positive;
     if (a[0] & 0x80)
         sign = Botan::BigInt::Negative;
 
     if (sign == Botan::BigInt::Negative)
         negate_binary(a.data(), a.size());
 
     d->n = Botan::BigInt::decode((const Botan::byte *)a.data(), a.size(), Botan::BigInt::Binary);
     d->n.set_sign(sign);
 }
 
 QString BigInteger::toString() const
 {
     QByteArray cs;
     try {
         cs.resize(d->n.encoded_size(Botan::BigInt::Decimal));
         Botan::BigInt::encode((Botan::byte *)cs.data(), d->n, Botan::BigInt::Decimal);
     } catch (std::exception &) {
         return QString();
     }
 
     QString str;
     if (d->n.is_negative())
         str += QLatin1Char('-');
     str += QString::fromLatin1(cs);
     str.remove(QChar::Null);
     return str;
 }
 
 bool BigInteger::fromString(const QString &s)
 {
     if (s.isEmpty())
         return false;
     const QByteArray cs = s.toLatin1();
 
     bool neg = false;
     if (s[0] == QLatin1Char('-'))
         neg = true;
 
     try {
         d->n = Botan::BigInt::decode(
             (const Botan::byte *)cs.data() + (neg ? 1 : 0), cs.length() - (neg ? 1 : 0), Botan::BigInt::Decimal);
     } catch (std::exception &) {
         return false;
     }
 
     if (neg)
         d->n.set_sign(Botan::BigInt::Negative);
     else
         d->n.set_sign(Botan::BigInt::Positive);
     return true;
 }
 
 }