OvmfPkg: Add C runtime apis referenced by Boringssl

BoringSSL is a fork of OpenSSL that is designed to meet Google's needs.
As documented at https://boringssl.googlesource.com/boringssl,
Boringssl manages Google's patches to openssl and is used in almost all of
Google products that rely on OpenSSL.
A fork of EDK2 forms the basis for the Uefi code in GCP compute and Google
would like to use Boringssl to work with it.
As part of that effort, there are many C runtime apis that get referenced
and are currently not implemented in EDK2.
This change adds those apis to edk2.
In particular, this change adds the following :
- Stubs for file functions added to CrtWrapper.c. These have been
implemented to return -1 rather than 0 since there is no file system
support. This will ensure that any calls into these apis will return
failure.
- Implementation of (strdup : string duplication function)
- Implementations of the following apis in CrtUtils.c, which are
referenced and used by the Boringssl code :
bsearch : binary search
getentropy : return entropy of requested length

Signed-off-by: Leena Soman <[email protected]>

CryptoPkg/Library/BaseCryptLib/BaseCryptLib.inf

@@ -65,6 +65,7 @@
   SysCall/CrtWrapper.c
   SysCall/TimerWrapper.c
   SysCall/BaseMemAllocation.c
+  SysCall/CrtUtils.c
 
 [Sources.Ia32]
   Rand/CryptRandTsc.c
@@ -99,6 +100,7 @@
   PrintLib
   UefiBootServicesTableLib
   SynchronizationLib
+  SafeIntLib
 
 [Protocols]
   gEfiMpServiceProtocolGuid

CryptoPkg/Library/BaseCryptLib/PeiCryptLib.inf

@@ -71,6 +71,7 @@
   SysCall/CrtWrapper.c
   SysCall/ConstantTimeClock.c
   SysCall/BaseMemAllocation.c
+  SysCall/CrtUtils.c
 
 [Packages]
   MdePkg/MdePkg.dec
@@ -87,6 +88,7 @@
   PeiServicesTablePointerLib
   PeiServicesLib
   SynchronizationLib
+  SafeIntLib
 
 [Ppis]
   gEfiPeiMpServicesPpiGuid

CryptoPkg/Library/BaseCryptLib/SecCryptLib.inf

@@ -60,6 +60,7 @@
   SysCall/CrtWrapper.c
   SysCall/ConstantTimeClock.c
   SysCall/BaseMemAllocation.c
+  SysCall/CrtUtils.c
 
 [Packages]
   MdePkg/MdePkg.dec
@@ -73,6 +74,7 @@
   OpensslLib
   IntrinsicLib
   PrintLib
+  SafeIntLib
 
 #
 # Remove these [BuildOptions] after this library is cleaned up

CryptoPkg/Library/BaseCryptLib/SmmCryptLib.inf

@@ -68,6 +68,7 @@
   SysCall/CrtWrapper.c
   SysCall/ConstantTimeClock.c
   SysCall/BaseMemAllocation.c
+  SysCall/CrtUtils.c
 
 [Sources.Ia32]
   Rand/CryptRandTsc.c
@@ -94,6 +95,7 @@
   PrintLib
   MmServicesTableLib
   SynchronizationLib
+  SafeIntLib
 
 #
 # Remove these [BuildOptions] after this library is cleaned up

CryptoPkg/Library/BaseCryptLib/SysCall/CrtUtils.c

@@ -0,0 +1,92 @@
+/** @file
+  C Run-Time Libraries (CRT) Utility apis for BoringSSL-based
+  Cryptographic Library.
+
+Copyright (c) 2009 - 2017, Intel Corporation. All rights reserved.<BR>
+SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include <CrtLibSupport.h>
+#include <Uefi/UefiBaseType.h>
+#include <Library/RngLib.h>
+#include <Library/SafeIntLib.h>
+
+/* Performs a binary search */
+void *
+bsearch (
+  const void *key,
+  const void *base,
+  size_t nmemb,
+  size_t size,
+  int         ( *compar )(const void *, const void *)
+  )
+{
+  void           *Mid;
+  int            Sign;
+  RETURN_STATUS  Status = RETURN_INVALID_PARAMETER;
+  size_t         Result;
+
+  if (!key || !base || !nmemb || !size) {
+    return NULL;
+  }
+
+  Status = SafeUintnMult ((UINTN)size, (UINTN)(nmemb/2), (UINTN *)&Result);
+
+  if ((Status == RETURN_BUFFER_TOO_SMALL) ||
+      (Status == RETURN_INVALID_PARAMETER))
+  {
+    return NULL;
+  }
+
+  while (nmemb > 0) {
+    Mid  = (char *)base + size * (nmemb/2);
+    Sign = compar (key, Mid);
+    if (Sign < 0) {
+      nmemb /= 2;
+    } else if (Sign > 0) {
+      base   = (char *)Mid + size;
+      nmemb -= nmemb/2 + 1;
+    } else {
+      return Mid;
+    }
+  }
+
+  return NULL;
+}
+
+/* Returns entropy of requested length in provided buffer */
+int
+getentropy (
+  void    *buffer,
+  size_t  length
+  )
+{
+  UINT8   *EntropyBuffer = (UINT8 *)buffer;
+  UINTN   Index;
+  UINT64  RandNum;
+  UINTN   CopyLength;
+
+  if (length > GETENTROPY_MAX) {
+    errno = EIO;
+    return -1;
+  }
+
+  if (EntropyBuffer == NULL) {
+    errno = EFAULT;
+    return -1;
+  }
+
+  for (Index = 0; Index < length; Index += sizeof (UINT64)) {
+    if (!GetRandomNumber64 (&RandNum)) {
+      errno = ENOSYS;
+      return -1;
+    }
+
+    CopyLength =
+      (length - Index >= sizeof (UINT64)) ? sizeof (UINT64) : (length - Index);
+    CopyMem (EntropyBuffer + Index, &RandNum, CopyLength);
+  }
+
+  return 0;
+}

CryptoPkg/Library/BaseCryptLib/SysCall/CrtWrapper.c

@@ -8,6 +8,9 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
 **/
 
 #include <CrtLibSupport.h>
+#include <Uefi/UefiBaseType.h>
+#include <Library/RngLib.h>
+#include <Library/SafeIntLib.h>
 
 int  errno = 0;
 
@@ -580,15 +583,99 @@ fopen (
 
 size_t
 fread (
-  void    *b,
-  size_t  c,
-  size_t  i,
-  FILE    *f
+  void    *ptr,
+  size_t  size,
+  size_t  nmemb,
+  FILE    *stream
   )
 {
   return 0;
 }
 
+int
+fputs (
+  const char  *s,
+  FILE        *stream
+  )
+{
+  return -1;
+}
+
+int
+fflush (
+  FILE  *stream
+  )
+{
+  return -1;
+}
+
+int
+ferror (
+  FILE  *stream
+  )
+{
+  return -1;
+}
+
+int
+fseek (
+  FILE  *stream,
+  long  offset,
+  int   whence
+  )
+{
+  return -1;
+}
+
+int
+feof (
+  FILE  *stream
+  )
+{
+  return -1;
+}
+
+int
+ftell (
+  FILE  *stream
+  )
+{
+  return -1;
+}
+
+char *
+fgets (
+  char  *s,
+  int   size,
+  FILE  *stream
+  )
+{
+  return NULL;
+}
+
+char *
+strdup (
+  char  *s
+  )
+{
+  UINTN  Length;
+  VOID   *Buffer;
+
+  if (!s) {
+    return NULL;
+  }
+
+  Length = strlen (s);
+
+  Buffer = malloc (Length);
+  if (Buffer == NULL) {
+    return NULL;
+  }
+
+  strncpy (Buffer, s, Length);
+  return Buffer;
+}
+
 uid_t
 getuid (
   void