/*

    File:       PPCToolboxKeychain.c

    Contains:   'osax' for creating PPC Toolbox keys in the keychain.

    Written by: Quinn "The Eskimo!"

    Copyright:  Copyright © 2000 by Apple Computer, Inc., All Rights Reserved.

    Disclaimer: IMPORTANT:  This Apple software is supplied to you by Apple Computer, Inc.

                ("Apple") in consideration of your agreement to the following terms, and your

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                constitutes acceptance of these terms.  If you do not agree with these terms,

                please do not use, install, modify or redistribute this Apple software.

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                to these terms, Apple grants you a personal, non-exclusive license, under AppleÕs

                copyrights in this original Apple software (the "Apple Software"), to use,

                reproduce, modify and redistribute the Apple Software, with or without

                modifications, in source and/or binary forms; provided that if you redistribute

                the Apple Software in its entirety and without modifications, you must retain

                this notice and the following text and disclaimers in all such redistributions of

                the Apple Software.  Neither the name, trademarks, service marks or logos of

                Apple Computer, Inc. may be used to endorse or promote products derived from the

                Apple Software without specific prior written permission from Apple.  Except as

                expressly stated in this notice, no other rights or licenses, express or implied,

                are granted by Apple herein, including but not limited to any patent rights that

                may be infringed by your derivative works or by other works in which the Apple

                Software may be incorporated.

                The Apple Software is provided by Apple on an "AS IS" basis.  APPLE MAKES NO

                WARRANTIES, EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION THE IMPLIED

                WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS FOR A PARTICULAR

                PURPOSE, REGARDING THE APPLE SOFTWARE OR ITS USE AND OPERATION ALONE OR IN

                COMBINATION WITH YOUR PRODUCTS.

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    Change History (most recent first):

*/

/////////////////////////////////////////////////////////////////

// MIB Setup

#include "MoreSetup.h"

// Mac OS Interfaces

#include <Keychain.h>

#include <CodeFragments.h>

#include <StringCompare.h>

#include <OpenTransportProviders.h>

// Standard C interfaces

#include <ctype.h>

#include <stdlib.h>

// MIB interfaces

#include "MoreAppleEvents.h"

// Apple Event Constants

#include "PPCToolboxKeychain.h"

/////////////////////////////////////////////////////////////////

#pragma mark ----- Global Data -----

static FSSpec gFragmentFSSpec;                          // location of osax file

static AEEventHandlerUPP gBlessKeyHandlerUPP = nil;     // -> BlessKeyHandlerProc

static Boolean gHaveInstalled = false;                  // have we installed our event handler

__declspec(export) UInt32 gAdditionReferenceCount = 0;  // required by AppleScript to prevent unload while busy

/////////////////////////////////////////////////////////////////

#pragma mark ----- Event Handlers -----

static Boolean CheckForChars(const char **cursor, const char *templ)

    // Assuming the *cursor is a pointer to an input string and

    // templ is a pointer to a constant template string,

    // check that *cursor starts with the characters in the template,

    // return true if the template is found or false otherwise.

    // Also updates *cursor as it ÔconsumesÕ characters.

    //

    // For example, if *cursor points to "eppc://foo" and

    // templ points to "eppc://", this will return true

    // and update *cursor to point to the the "f" in "foo".

{

    MoreAssertQ(cursor != nil);

    MoreAssertQ(*cursor != nil);

    MoreAssertQ(templ != nil);

    while (**cursor == *templ && *templ != 0) {

        *cursor += 1;

        templ += 1;

    }

    return *templ == 0;

}

static Boolean CollectChars(const char **cursor, char terminator, UInt8 *buffer, ByteCount bufferSize, ByteCount *actualSize)

    // Copies characters from an input string (pointed to be *cursor ) to an output buffer

    // (described by buffer and bufferSize), terminating when either a) we hit a null terminator

    // in *cursor, or when we hit the terminator character in the input string.  Updates

    // *cursor to point to the terminating character.  Also returns, in *actualSize, the number

    // of bytes that were copied to the buffer.  Converts escape sequences (%xx) into the

    // appropriate character in the output buffer.

    // 

    // Returns true if the copy was successful, or false if it failed.  Reasons for failure

    // include a) running out of space in the output buffer, b) a bogus escape sequence, or

    // c) not copying any characters to the output buffer (null output is not allowed).

{

    Boolean result;

    MoreAssertQ(cursor  != nil);

    MoreAssertQ(*cursor != nil);

    MoreAssertQ(buffer  != nil);

    MoreAssertQ(actualSize != nil);

    *actualSize = 0;

    result = true;

    do {

        // If weÕre run out of input characters, leave with result true.

        if ( **cursor == 0 || **cursor == terminator ) {

            break;

        }

        // We know weÕre going for another output character.  If we donÕt have enough

        // space, fail with an error.

        if ( *actualSize == bufferSize ) {

            result = false;

            break;

        }

        // Now look for a '%'; if we find one, interpret the digits that follow as hex.

        // Otherwise just copy the character across.

        if (**cursor == '%') {

            char tmpStr[3];

            *cursor += 1;       // skip '%'

            tmpStr[0] = (*cursor)[0];

            tmpStr[1] = (*cursor)[1];

            tmpStr[2] = 0;

            if ( ! isxdigit(tmpStr[0]) || ! isxdigit(tmpStr[1]) ) {

                result = false;

                break;

            }

            *cursor += 2;       // skip hex digits

            buffer[*actualSize] = (UInt8) strtoul(tmpStr, nil, 16);;

        } else {

            buffer[*actualSize] = (UInt8) **cursor;

            *cursor += 1;

        }

        *actualSize += 1;

    } while (true);

    // If we didnÕt copy across /any/ characters, thatÕs an error.

    if (result && *actualSize == 0) {

        result = false;

    }

    return result;

}

static OSStatus ParseURLIntoGenericData(const char *url, UInt8 *genaBuffer, ByteCount *genaBufferSize)

    // Parses strings of the form eppc://dns.name or eppc:/at/machine:zone

    // into the appropriate 'gena' attribute format (either a packed NBPEntity

    // or a LocationNameRec with locationKindSelector of ppcXTIAddrLocation).

{

    OSStatus err;

    const char *cursor;

    LocationNamePtr loc;

    ByteCount actualSize;

    UInt8 *outputCursor;

    MoreAssertQ(url != nil);

    MoreAssertQ(genaBuffer != nil);

    MoreAssertQ(genaBufferSize != nil);

    err = -1;

    cursor = url;

    if ( ! CheckForChars(&cursor, "eppc:/") ) goto parseError;

    switch (*cursor) {

        case '/':

            // eppc://dns.name

            // For TCP/IP, the 'gena' attribute for a PPC Toolbox key is in the

            // same LocationNameRec format used when sending Apple events over TCP/IP.

            // See DTS Technote 1176 for more details.

            // 

            // <http://developer.apple.com/technotes/tn/tn1176.html#ppctoolbox>

            cursor += 1;

            loc = (LocationNamePtr) genaBuffer;

            loc->locationKindSelector  = ppcXTIAddrLocation;

            loc->u.xtiType.Reserved[0] = 0;

            loc->u.xtiType.Reserved[1] = 0;

            loc->u.xtiType.Reserved[2] = 0;

            loc->u.xtiType.xtiAddr.fAddressType = AF_DNS;

            if ( ! CollectChars(&cursor, 0, loc->u.xtiType.xtiAddr.fAddress, sizeof(loc->u.xtiType.xtiAddr.fAddress), &actualSize) ) goto parseError;

            if ( *cursor != 0) goto parseError;

            loc->u.xtiType.xtiAddrLen = sizeof(PPCXTIAddressType) + actualSize;

            *genaBufferSize = loc->u.xtiType.xtiAddrLen + sizeof(loc->locationKindSelector) 

                                                        + sizeof(loc->u.xtiType.Reserved) 

                                                        + sizeof(loc->u.xtiType.xtiAddrLen);

            break;

        case 'a':

            // eppc:/at/machine:zone

            // For AppleTalk, the 'gena' attribute for a PPC Toolbox key is in the

            // standard NBPEntity format (ie three packed Pascal strings, each of

            // 32 characters or less).

            if ( ! CheckForChars(&cursor, "at/") ) goto parseError;

            outputCursor = genaBuffer;

            if ( ! CollectChars(&cursor, ':', outputCursor + 1, 32, &actualSize) ) goto parseError;

            if ( *cursor != ':') goto parseError;

            cursor += 1;

            *outputCursor = actualSize;

            outputCursor += *outputCursor + 1;

            BlockMove("\pPPCToolBox", outputCursor, 11);

            outputCursor += 11;

            if ( ! CollectChars(&cursor, '0', outputCursor + 1, 32, &actualSize) ) goto parseError;

            if ( *cursor != 0) goto parseError;

            *outputCursor = actualSize;

            outputCursor += *outputCursor + 1;

            *genaBufferSize = outputCursor - genaBuffer;

            break;

        default:

            goto parseError;

    }

    err = noErr;

parseError:

    return err;

}

static pascal OSErr BlessKeyHandlerProc(const AppleEvent *theAppleEvent, AppleEvent *reply, UInt32 handlerRefcon)

    // The Apple event handler installed by our osax's fragment initialisation routine.

    // This handler extracts the event parameters ("name" and "addr"), looks up the 

    // generic key by name in the default keychain, then parses the "addr" URL into

    // a 'gena' key attribute and stores that attribute in the key.

{

    OSStatus    err;

    OSStatus    junk;

    AEDesc      nameDesc;

    AEDesc      addrDesc;

    Str255      name;

    char        addr[256];

    KCItemRef   foundItem;

    UInt8       genaBuffer[256];

    ByteCount   genaBufferSize;

    MoreAssertQ(theAppleEvent != nil);

    MoreAssertQ(reply != nil);

    #if MORE_DEBUG

        MoreAssertQ(handlerRefcon == 0);

    #else

        #pragma unused(handlerRefcon)

    #endif

    gAdditionReferenceCount += 1;       // tell AppleScript weÕre busy

    MoreAENullDesc(&nameDesc);

    MoreAENullDesc(&addrDesc);

    foundItem = nil;

    err = noErr;

    if ( !(KeychainManagerAvailable()) ) {

        err = unimpErr;

    }

    err = AEGetParamDesc(theAppleEvent, keyAEName, typeText, &nameDesc);

    if (err == noErr) {

        err = MoreAEGetPStringFromDescriptor(&nameDesc, name);

    }

    if (err == noErr) {

        err = AEGetParamDesc(theAppleEvent, kAEISClientAddress, typeText, &addrDesc);

    }

    if (err == noErr) {

        err = MoreAEGetCStringFromDescriptor(&addrDesc, addr);

    }

    if (err == noErr) {

        err = MoreAEGotRequiredParams(theAppleEvent);

    }

    if (err == noErr) {

        err = KCFindGenericPassword(name, nil, 0, nil, 0, &foundItem);

    }

    if (err == noErr) {

        genaBufferSize = sizeof(genaBuffer);

        err = ParseURLIntoGenericData(addr, genaBuffer, &genaBufferSize);

    }

    if (err == noErr) {

        KCAttribute attr;

        attr.tag    = kGenericKCItemAttr;

        attr.length = genaBufferSize;

        attr.data   = genaBuffer;

        err = KCSetAttribute(foundItem, &attr);

    }

    if (err == noErr) {

        err = KCUpdateItem(foundItem);

    }

    if (reply->dataHandle != nil) {

        // Need to put the an error string into the keyErrorString parameter of

        // reply here.  Only necessary for errors that AppleScript doesnÕt already 

        // know about, such as the unimpErr we generate if Keychain isn't available.

        // This code is left as an exercise for the reader.

    }

    if (foundItem != nil) {

        junk = KCReleaseItem(&foundItem);

        MoreAssertQ(junk == noErr);

    }

    MoreAEDisposeDesc(&nameDesc);

    MoreAEDisposeDesc(&addrDesc);

    gAdditionReferenceCount -= 1;       // tell AppleScript weÕre no longer busy

    return err;

}

/////////////////////////////////////////////////////////////////

#pragma mark ----- Init/Term -----

extern OSErr FragmentInit(const CFragInitBlock *initBlock);

extern void  FragmentTerm(void);

extern OSErr FragmentInit(const CFragInitBlock *initBlock)

    // This routine is the native osax's fragment initialization

    // routine.  ItÕs responsible for installing our event handler.

{

    OSStatus err;

    #if MORE_DEBUG

        DebugStr("\pFragmentInit");

    #endif

    MoreAssertQ(gAdditionReferenceCount == 0);  // Either the data initialization failed, or something else bad has happened.

    // We latch the FSSpec of the 'osax' file in case we need to access

    // our resource fork.  We currently donÕt use this info, but a future

    // extensions might use it (to get better error numbers, for example).

    MoreAssertQ(initBlock->fragLocator.where == kDataForkCFragLocator);

    gFragmentFSSpec = *(initBlock->fragLocator.u.onDisk.fileSpec);

    // Install the handler.

    err = noErr;

    gBlessKeyHandlerUPP = NewAEEventHandlerUPP(BlessKeyHandlerProc);

    if (gBlessKeyHandlerUPP == nil) {

        err = memFullErr;

    }

    if (err == noErr) {

        err = AEInstallEventHandler(kBlessKeyClassID, kBlessKeyEventID, gBlessKeyHandlerUPP, 0, true);

        gHaveInstalled = (err == noErr);

    }

    // Clean up.

    if (err != noErr) {

        FragmentTerm();

    }

    return err;

}

extern void  FragmentTerm(void)

    // This routine is the native osax's fragment termination

    // routine.  ItÕs responsible for tearing down any initialization

    // done by FragmentInit.

{

    OSStatus junk;

    #if MORE_DEBUG

        DebugStr("\pFragmentTerm");

    #endif

    MoreAssertQ(gAdditionReferenceCount == 0);  // Why are we being unloaded if weÕre busy?

    if (gHaveInstalled) {

        MoreAssertQ(gBlessKeyHandlerUPP != nil);

        junk = AERemoveEventHandler(kBlessKeyClassID, kBlessKeyEventID, gBlessKeyHandlerUPP, true);

        MoreAssertQ(junk == noErr);

        gHaveInstalled = false;

    }

    if (gBlessKeyHandlerUPP != nil) {

        DisposeAEEventHandlerUPP(gBlessKeyHandlerUPP);

        gBlessKeyHandlerUPP = nil;

    }

}

#ifdef PPCTOOLBOX_KEYCHAIN_TESTBED

// The code inside this conditional is only used by the Testbed

// target to create a testbed application that letÕs us debug

// the core of the 'osax' without having to mess around debugging

// code resources.

#include <stdio.h>

static void TestParseURL(const char *url)

{

    OSStatus err;

    UInt8 genaBuf[256];

    ByteCount genaBufSize;

    ByteCount thisByteIndex;

    genaBufSize = sizeof(genaBuf);

    err = ParseURLIntoGenericData(url, genaBuf, &genaBufSize);

    if (err == noErr) {

        printf("ParseURLIntoGenericData(%s) = \n", url);

        for (thisByteIndex = 0; thisByteIndex < genaBufSize; thisByteIndex++) {

            printf("%02x ", genaBuf[thisByteIndex]);

        }

        printf("\n");

    } else {

        printf("¥¥¥ ParseURLIntoGenericData(%s), err = %ld\n", url, err);

    }

}

extern void main(void)

{

    printf("PPCToolboxKeychain Testbed!\n");

    // Ã means test should succeed

    // x means test should fail

    TestParseURL("eppc://guy-smiley.apple.com");            // Ã

    TestParseURL("eppc:/at/Guy Smiley:*");                  // Ã

    TestParseURL("foo");                                    // x

    TestParseURL("eppc:");                                  // x

    TestParseURL("eppc:/");                                 // x

    TestParseURL("eppc://");                                // x

    TestParseURL("eppc:/bob/");                             // x

    TestParseURL("eppc:/ab/");                              // x

    TestParseURL("eppc:/at/");                              // x

    TestParseURL("eppc:/at/machine");                       // x

    TestParseURL("eppc:/at/machine:");                      // x

    TestParseURL("eppc:/at/:");                             // x

    TestParseURL("eppc:/at/:zone");                         // x

    TestParseURL("eppc:/at/machine:zone");                  // Ã

    TestParseURL("eppc:/at/machine%3Awith%3Acolons:zone");  // Ã

    TestParseURL("eppc:/at/01234567890123456789012345678901:zone");         // Ã

    TestParseURL("eppc:/at/012345678901234567890123456789012:zone");        // x

    TestParseURL("eppc://%");                               // x

    TestParseURL("eppc://%x");                              // x

    TestParseURL("eppc://%xy");                             // x

    printf("Done.  Press command-Q to Quit.\n");

}

#endif