ShellPkg: refine command line parsing

Correctly divide up parameters for Argc/Argv including quote ("), escape (^), and space ( ) processing.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jaben Carsey <Jaben.carsey@intel.com>
Reviewed-by: Joe Peterson <joe.peterson@intel.com>
Reviewed-by: Tapan Shah <tapandshah@hp.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@16673 6f19259b-4bc3-4df7-8a09-765794883524

3 files changed, 214 insertions, 119 deletions

diff --git a/ShellPkg/Application/Shell/Shell.c b/ShellPkg/Application/Shell/Shell.c
index a570b7b..7eaccb7 100644
--- a/ShellPkg/Application/Shell/Shell.c
+++ b/ShellPkg/Application/Shell/Shell.c
@@ -1870,12 +1870,12 @@ IsValidSplit(
       return (EFI_OUT_OF_RESOURCES);

     }

     TempWalker = (CHAR16*)Temp;

-    GetNextParameter(&TempWalker, &FirstParameter, StrSize(CmdLine));

-

-    if (GetOperationType(FirstParameter) == Unknown_Invalid) {

-      ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_SHELL_NOT_FOUND), ShellInfoObject.HiiHandle, FirstParameter);

-      SetLastError(SHELL_NOT_FOUND);

-      Status = EFI_NOT_FOUND;

+    if (!EFI_ERROR(GetNextParameter(&TempWalker, &FirstParameter, StrSize(CmdLine)))) {

+      if (GetOperationType(FirstParameter) == Unknown_Invalid) {

+        ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_SHELL_NOT_FOUND), ShellInfoObject.HiiHandle, FirstParameter);

+        SetLastError(SHELL_NOT_FOUND);

+        Status = EFI_NOT_FOUND;

+      }

     }

   }

 

@@ -2030,24 +2030,25 @@ DoHelpUpdate(
   Walker = *CmdLine;

   while(Walker != NULL && *Walker != CHAR_NULL) {

     LastWalker = Walker;

-    GetNextParameter(&Walker, &CurrentParameter, StrSize(*CmdLine));

-    if (StrStr(CurrentParameter, L"-?") == CurrentParameter) {

-      LastWalker[0] = L' ';

-      LastWalker[1] = L' ';

-      NewCommandLine = AllocateZeroPool(StrSize(L"help ") + StrSize(*CmdLine));

-      if (NewCommandLine == NULL) {

-        Status = EFI_OUT_OF_RESOURCES;

+    if (!EFI_ERROR(GetNextParameter(&Walker, &CurrentParameter, StrSize(*CmdLine)))) {

+      if (StrStr(CurrentParameter, L"-?") == CurrentParameter) {

+        LastWalker[0] = L' ';

+        LastWalker[1] = L' ';

+        NewCommandLine = AllocateZeroPool(StrSize(L"help ") + StrSize(*CmdLine));

+        if (NewCommandLine == NULL) {

+          Status = EFI_OUT_OF_RESOURCES;

+          break;

+        }

+

+        //

+        // We know the space is sufficient since we just calculated it.

+        //

+        StrnCpy(NewCommandLine, L"help ", 5);

+        StrnCat(NewCommandLine, *CmdLine, StrLen(*CmdLine));

+        SHELL_FREE_NON_NULL(*CmdLine);

+        *CmdLine = NewCommandLine;

         break;

       }

-

-      //

-      // We know the space is sufficient since we just calculated it.

-      //

-      StrnCpy(NewCommandLine, L"help ", 5);

-      StrnCat(NewCommandLine, *CmdLine, StrLen(*CmdLine));

-      SHELL_FREE_NON_NULL(*CmdLine);

-      *CmdLine = NewCommandLine;

-      break;

     }

   }

 

@@ -2499,27 +2500,30 @@ RunCommand(
     return (EFI_OUT_OF_RESOURCES);

   }

   TempWalker = CleanOriginal;

-  GetNextParameter(&TempWalker, &FirstParameter, StrSize(CleanOriginal));

-

-  //

-  // Depending on the first parameter we change the behavior

-  //

-  switch (Type = GetOperationType(FirstParameter)) {

-    case   File_Sys_Change:

-      Status = ChangeMappedDrive (FirstParameter);

-      break;

-    case   Internal_Command:

-    case   Script_File_Name:

-    case   Efi_Application:

-      Status = SetupAndRunCommandOrFile(Type, CleanOriginal, FirstParameter, ShellInfoObject.NewShellParametersProtocol);

-      break;

-    default:

-      //

-      // Whatever was typed, it was invalid.

-      //

-      ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_SHELL_NOT_FOUND), ShellInfoObject.HiiHandle, FirstParameter);

-      SetLastError(SHELL_NOT_FOUND);

-      break;

+  if (!EFI_ERROR(GetNextParameter(&TempWalker, &FirstParameter, StrSize(CleanOriginal)))) {

+    //

+    // Depending on the first parameter we change the behavior

+    //

+    switch (Type = GetOperationType(FirstParameter)) {

+      case   File_Sys_Change:

+        Status = ChangeMappedDrive (FirstParameter);

+        break;

+      case   Internal_Command:

+      case   Script_File_Name:

+      case   Efi_Application:

+        Status = SetupAndRunCommandOrFile(Type, CleanOriginal, FirstParameter, ShellInfoObject.NewShellParametersProtocol);

+        break;

+      default:

+        //

+        // Whatever was typed, it was invalid.

+        //

+        ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_SHELL_NOT_FOUND), ShellInfoObject.HiiHandle, FirstParameter);

+        SetLastError(SHELL_NOT_FOUND);

+        break;

+    }

+  } else {

+    ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_SHELL_NOT_FOUND), ShellInfoObject.HiiHandle, FirstParameter);

+    SetLastError(SHELL_NOT_FOUND);

   }

  

   SHELL_FREE_NON_NULL(CleanOriginal);

diff --git a/ShellPkg/Application/Shell/ShellParametersProtocol.c b/ShellPkg/Application/Shell/ShellParametersProtocol.c
index 452c4c1..3f86524 100644
--- a/ShellPkg/Application/Shell/ShellParametersProtocol.c
+++ b/ShellPkg/Application/Shell/ShellParametersProtocol.c
@@ -4,7 +4,7 @@
 

   Copyright (C) 2014, Red Hat, Inc.

   Copyright (c) 2013 Hewlett-Packard Development Company, L.P.

-  Copyright (c) 2009 - 2014, Intel Corporation. All rights reserved.<BR>

+  Copyright (c) 2009 - 2015, Intel Corporation. All rights reserved.<BR>

   This program and the accompanying materials

   are licensed and made available under the terms and conditions of the BSD License

   which accompanies this distribution.  The full text of the license may be found at

@@ -18,7 +18,79 @@
 #include "Shell.h"

 

 /**

-  return the next parameter from a command line string;

+  Return the next location of a non-escaped character from a command line string;

+

+  @param[in] String        the string to parse

+  @param[in] Character     the character to look for

+

+  @retval the location of the character in the string or the end of the string

+**/

+CONST CHAR16*

+EFIAPI

+FindCharacter(

+  IN CONST CHAR16 *String,

+  IN CONST CHAR16 Character

+  )

+{

+  CONST CHAR16 *Walker;

+

+  for (Walker = String ; *Walker != Character && *Walker != CHAR_NULL; Walker++) {

+    if (*Walker == L'^') {

+      Walker++;

+    }

+  }

+  return Walker;

+}

+

+/**

+  Return the next parameter's end from a command line string;

+

+  @param[in] String        the string to parse

+**/

+CONST CHAR16*

+EFIAPI

+FindEndOfParameter(

+  IN CONST CHAR16 *String

+  )

+{

+  CONST CHAR16 *NextSpace;

+  CONST CHAR16 *NextQuote;

+  CONST CHAR16 *First;

+  CONST CHAR16 *CloseQuote;

+

+  NextSpace = FindCharacter (String, L' ' );

+  NextQuote = FindCharacter (String, L'\"');

+  First = MIN (NextQuote, NextSpace);

+

+  //

+  // nothing, all one parameter remaining

+  //

+  if (*First == CHAR_NULL) {

+    return (First);

+  }

+

+  //

+  // If space before a quote (or neither found, i.e. both CHAR_NULL),

+  // then that's the end.

+  //

+  if (First == NextSpace) {

+    return (NextSpace);

+  }

+

+  CloseQuote = FindCharacter (First+1, L'\"');

+

+  //

+  // We did not find a terminator... return the end of the string

+  //

+  if (*CloseQuote == CHAR_NULL) {

+    return (NULL);

+  }

+

+  return (FindEndOfParameter (CloseQuote+1));

+}

+

+/**

+  Return the next parameter from a command line string;

 

   This function moves the next parameter from Walker into TempParameter and moves

   Walker up past that parameter for recursive calling.  When the final parameter

@@ -27,12 +99,17 @@
   Temp Parameter must be large enough to hold the parameter before calling this

   function.

 

+  This will also remove all remaining ^ characters after processing.

+

   @param[in, out] Walker        pointer to string of command line.  Adjusted to

                                 reminaing command line on return

   @param[in, out] TempParameter pointer to string of command line item extracted.

   @param[in]      Length        buffer size of TempParameter.

+

+  @return   EFI_INALID_PARAMETER  A required parameter was NULL or pointed to a NULL or empty string.

+  @return   EFI_NOT_FOUND         A closing " could not be found on the specified string

 **/

-VOID

+EFI_STATUS

 EFIAPI

 GetNextParameter(

   IN OUT CHAR16   **Walker,

@@ -41,12 +118,15 @@ GetNextParameter(
   )

 {

   CHAR16 *NextDelim;

-  CHAR16 *TempLoc;

 

-  ASSERT(Walker           != NULL);

-  ASSERT(*Walker          != NULL);

-  ASSERT(TempParameter    != NULL);

-  ASSERT(*TempParameter   != NULL);

+  if (Walker           == NULL

+    ||*Walker          == NULL

+    ||TempParameter    == NULL

+    ||*TempParameter   == NULL

+    ){

+    return (EFI_INVALID_PARAMETER);

+  }

+

 

   //

   // make sure we dont have any leading spaces

@@ -59,81 +139,80 @@ GetNextParameter(
   // make sure we still have some params now...

   //

   if (StrLen(*Walker) == 0) {

-    ASSERT((*Walker)[0] == CHAR_NULL);

-    *Walker = NULL;

-    return;

+DEBUG_CODE_BEGIN();

+    *Walker        = NULL;

+DEBUG_CODE_END();

+    return (EFI_INVALID_PARAMETER);

+  }

+

+  NextDelim = (CHAR16*)FindEndOfParameter(*Walker);

+

+  if (NextDelim == NULL){

+DEBUG_CODE_BEGIN();

+    *Walker        = NULL;

+DEBUG_CODE_END();

+    return (EFI_NOT_FOUND);

   }

 

+  StrnCpy(*TempParameter, (*Walker), NextDelim - *Walker);

+

   //

-  // we have a quoted parameter

-  // could be the last parameter, but SHOULD have a trailing quote

+  // Add a CHAR_NULL if we didnt get one via the copy

   //

-  if ((*Walker)[0] == L'\"') {

-    NextDelim = NULL;

-    for (TempLoc = *Walker + 1 ; TempLoc != NULL && *TempLoc != CHAR_NULL ; TempLoc++) {

-      if (*TempLoc == L'^' && *(TempLoc+1) == L'\"') {

-        TempLoc++;

-      } else if (*TempLoc == L'\"') {

-        NextDelim = TempLoc;

-        break;

-      }

-    }

+  if (*NextDelim != CHAR_NULL) {

+    (*TempParameter)[NextDelim - *Walker] = CHAR_NULL;

+  }

 

-    if (NextDelim - ((*Walker)+1) == 0) {

-      //

-      // found ""

-      //

-      *(*TempParameter) = CHAR_NULL;

-      *Walker = NextDelim + 1;

-    } else if (NextDelim != NULL) {

+  *Walker = NextDelim;

 

-      //

-      // Copy ensuring that both quotes are left in place.

-      //

-      StrnCpy(*TempParameter, (*Walker), NextDelim - *Walker + 1);

-      *Walker = NextDelim + 1;

-    } else {

-      //

-      // last one... someone forgot the training quote!

-      //

-      StrnCpy(*TempParameter, *Walker, Length/sizeof(CHAR16) - 1);

-      *Walker = NULL;

-    }

-    for (TempLoc = *TempParameter ; TempLoc != NULL && *TempLoc != CHAR_NULL ; TempLoc++) {

-      if (*TempLoc == L'^' && *(TempLoc+1) == L'\"') {

-        CopyMem(TempLoc, TempLoc+1, StrSize(TempLoc) - sizeof(TempLoc[0]));

-      }

-    }

-  } else {

+  //

+  // Now remove any quotes surrounding entire parameters

+  //

+  if ((*TempParameter)[0] == L'\"' && (*TempParameter)[StrLen (*TempParameter)-1] == L'\"') {

+    (*TempParameter)[StrLen (*TempParameter)-1] = CHAR_NULL;

+    CopyMem ((*TempParameter), (*TempParameter)+1, StrSize ((*TempParameter)+1));

+  }

+

+  //

+  // Remove any non-escaped quotes in the string

+  //

+  for (NextDelim = StrStr(*TempParameter, L"\""); NextDelim != NULL && *NextDelim != CHAR_NULL; NextDelim = StrStr(NextDelim, L"\"")) {

+    //

+    // Make sure I found a quote character properly.

     //

-    // we have a regular parameter (no quote) OR

-    // we have the final parameter (no trailing space)

+    ASSERT(*NextDelim == L'\"');

+

     //

-    NextDelim = StrStr((*Walker), L" ");

-    if (NextDelim != NULL) {

-      StrnCpy(*TempParameter, *Walker, NextDelim - (*Walker));

-      (*TempParameter)[NextDelim - (*Walker)] = CHAR_NULL;

-      *Walker = NextDelim+1;

+    // Only remove quotes that do not have a preceeding ^

+    //

+    if ((NextDelim > (*TempParameter) && (*(NextDelim - 1) != L'^')) || (NextDelim == (*TempParameter))) {

+      CopyMem (NextDelim, NextDelim + 1, StrSize (NextDelim + 1));

     } else {

-      //

-      // last one.

-      //

-      StrnCpy(*TempParameter, *Walker, Length/sizeof(CHAR16) - 1);

-      *Walker = NULL;

-    }

-    for (NextDelim = *TempParameter ; NextDelim != NULL && *NextDelim != CHAR_NULL ; NextDelim++) {

-      if (*NextDelim == L'^' && *(NextDelim+1) == L'^') {

-        CopyMem(NextDelim, NextDelim+1, StrSize(NextDelim) - sizeof(NextDelim[0]));

-      }

-    }

-    while ((*TempParameter)[StrLen(*TempParameter)-1] == L' ') {

-      (*TempParameter)[StrLen(*TempParameter)-1] = CHAR_NULL;

+      NextDelim++;

     }

-    while ((*TempParameter)[0] == L' ') {

-      CopyMem(*TempParameter, (*TempParameter)+1, StrSize(*TempParameter) - sizeof((*TempParameter)[0]));

+  }

+

+  //

+  // Remove any escape charactersin the parameter before returning it

+  // all escape character processing is complete at this time

+  //

+  for (NextDelim = StrStr(*TempParameter, L"^"); NextDelim != NULL && *NextDelim != CHAR_NULL; NextDelim = StrStr(NextDelim, L"^")) {

+    //

+    // Make sure I found an escape character properly.

+    //

+    ASSERT(*NextDelim == L'^');

+

+    CopyMem (NextDelim, NextDelim + 1, StrSize (NextDelim + 1));

+

+    //

+    // If we had 2 escapes in a row, leave one behind

+    //

+    if (*NextDelim == L'^') {

+      NextDelim++;

     }

   }

-  return;

+

+  return EFI_SUCCESS;

 }

 

 /**

@@ -143,6 +222,9 @@ GetNextParameter(
   parameters for inclusion in EFI_SHELL_PARAMETERS_PROTOCOL.  this supports space

   delimited and quote surrounded parameter definition.

 

+  All special character processing (alias, environment variable, redirection, 

+  etc... must be complete before calling this API.

+

   @param[in] CommandLine         String of command line to parse

   @param[in, out] Argv           pointer to array of strings; one for each parameter

   @param[in, out] Argc           pointer to number of strings in Argv array

@@ -182,9 +264,12 @@ ParseCommandLineToArgs(
   for ( Count = 0

       , Walker = (CHAR16*)CommandLine

       ; Walker != NULL && *Walker != CHAR_NULL

-      ; GetNextParameter(&Walker, &TempParameter, Size)

-      , Count++

-     );

+      ; Count++

+      ) {

+    if (EFI_ERROR(GetNextParameter(&Walker, &TempParameter, Size))) {

+      break;

+    }

+  }

 

   //

   // lets allocate the pointer array

@@ -199,7 +284,11 @@ ParseCommandLineToArgs(
   Walker = (CHAR16*)CommandLine;

   while(Walker != NULL && *Walker != CHAR_NULL) {

     SetMem16(TempParameter, Size, CHAR_NULL);

-    GetNextParameter(&Walker, &TempParameter, Size);

+    if (EFI_ERROR(GetNextParameter(&Walker, &TempParameter, Size))) {

+      SHELL_FREE_NON_NULL(TempParameter);

+      return (EFI_INVALID_PARAMETER);

+    }

+

     NewParam = AllocateCopyPool(StrSize(TempParameter), TempParameter);

     if (NewParam == NULL){

       SHELL_FREE_NON_NULL(TempParameter);

diff --git a/ShellPkg/Application/Shell/ShellParametersProtocol.h b/ShellPkg/Application/Shell/ShellParametersProtocol.h
index 15b76b7..2fd8f8c 100644
--- a/ShellPkg/Application/Shell/ShellParametersProtocol.h
+++ b/ShellPkg/Application/Shell/ShellParametersProtocol.h
@@ -192,8 +192,10 @@ ParseCommandLineToArgs(
   @param[in, out] TempParameter pointer to string of command line item extracted.

   @param[in]      Length        Length of (*TempParameter) in bytes

 

+  @return   EFI_INALID_PARAMETER  A required parameter was NULL or pointed to a NULL or empty string.

+  @return   EFI_NOT_FOUND         A closing " could not be found on the specified string

 **/

-VOID

+EFI_STATUS

 EFIAPI

 GetNextParameter(

   IN OUT CHAR16   **Walker,