/*
nslcd-prot.h - helper macros for reading and writing in protocol streams
Copyright (C) 2006 West Consulting
Copyright (C) 2006-2014 Arthur de Jong
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
*/
#ifndef COMMON__NSLCD_PROT_H
#define COMMON__NSLCD_PROT_H 1
#include <arpa/inet.h>
#include <netinet/in.h>
#include "tio.h"
/* If you use these macros you should define the following macros to
handle error conditions (these marcos should clean up and return from the
function):
ERROR_OUT_WRITEERROR(fp)
ERROR_OUT_READERROR(fp)
ERROR_OUT_BUFERROR(fp)
ERROR_OUT_NOSUCCESS(fp) */
/* Debugging marcos that can be used to enable detailed protocol logging,
pass -DDEBUG_PROT to do overall protocol debugging, and -DDEBUG_PROT_DUMP
to dump the actual bytestream. */
#ifdef DEBUG_PROT
/* define a debugging macro to output logging */
#include <string.h>
#include <errno.h>
#define DEBUG_PRINT(fmt, arg) \
fprintf(stderr, "%s:%d:%s: " fmt "\n", __FILE__, __LINE__, \
__PRETTY_FUNCTION__, arg);
#else /* DEBUG_PROT */
/* define an empty debug macro to disable logging */
#define DEBUG_PRINT(fmt, arg)
#endif /* not DEBUG_PROT */
#ifdef DEBUG_PROT_DUMP
/* define a debugging macro to output detailed logging */
#ifdef HAVE_STDINT_H
#include <stdint.h>
#endif /* HAVE_STDINT_H */
static void debug_dump(const void *ptr, size_t size)
{
int i;
for (i = 0; i < size; i++)
fprintf(stderr, " %02x", ((const uint8_t *)ptr)[i]);
fprintf(stderr, "\n");
}
#define DEBUG_DUMP(ptr, size) \
fprintf(stderr, "%s:%d:%s:", __FILE__, __LINE__, __PRETTY_FUNCTION__); \
debug_dump(ptr, size);
#else /* DEBUG_PROT_DUMP */
/* define an empty debug macro to disable logging */
#define DEBUG_DUMP(ptr, size)
#endif /* not DEBUG_PROT_DUMP */
/* WRITE marcos, used for writing data, on write error they will
call the ERROR_OUT_WRITEERROR macro
these macros may require the availability of the following
variables:
int32_t tmpint32; - temporary variable
*/
#define WRITE(fp, ptr, size) \
DEBUG_PRINT("WRITE : var="__STRING(ptr)" size=%d", (int)size); \
DEBUG_DUMP(ptr, size); \
if (tio_write(fp, ptr, (size_t)size)) \
{ \
DEBUG_PRINT("WRITE : var="__STRING(ptr)" error: %s", \
strerror(errno)); \
ERROR_OUT_WRITEERROR(fp); \
}
#define WRITE_INT32(fp, i) \
DEBUG_PRINT("WRITE_INT32 : var="__STRING(i)" int32=%08x", (int)i); \
tmpint32 = htonl((int32_t)(i)); \
WRITE(fp, &tmpint32, sizeof(int32_t))
#define WRITE_STRING(fp, str) \
DEBUG_PRINT("WRITE_STRING: var="__STRING(str)" string=\"%s\"", (str)); \
if ((str) == NULL) \
{ \
WRITE_INT32(fp, 0); \
} \
else \
{ \
WRITE_INT32(fp, strlen(str)); \
tmpint32 = ntohl(tmpint32); \
if (tmpint32 > 0) \
{ \
WRITE(fp, (str), tmpint32); \
} \
}
#define WRITE_STRINGLIST(fp, arr) \
if ((arr) == NULL) \
{ \
DEBUG_PRINT("WRITE_STRLST: var="__STRING(arr)" num=%d", 0); \
WRITE_INT32(fp, 0); \
} \
else \
{ \
/* first determine length of array */ \
for (tmp3int32 = 0; (arr)[tmp3int32] != NULL; tmp3int32++) \
/* noting */ ; \
/* write number of strings */ \
DEBUG_PRINT("WRITE_STRLST: var="__STRING(arr)" num=%d", (int)tmp3int32); \
WRITE_INT32(fp, tmp3int32); \
/* write strings */ \
for (tmp2int32 = 0; tmp2int32 < tmp3int32; tmp2int32++) \
{ \
WRITE_STRING(fp, (arr)[tmp2int32]); \
} \
}
#define WRITE_STRINGLIST_EXCEPT(fp, arr, not) \
/* first determine length of array */ \
tmp3int32 = 0; \
for (tmp2int32 = 0; (arr)[tmp2int32] != NULL; tmp2int32++) \
if (strcmp((arr)[tmp2int32], (not)) != 0) \
tmp3int32++; \
/* write number of strings (mius one because we intend to skip one) */ \
DEBUG_PRINT("WRITE_STRLST: var="__STRING(arr)" num=%d", (int)tmp3int32); \
WRITE_INT32(fp, tmp3int32); \
/* write strings */ \
for (tmp2int32 = 0; (arr)[tmp2int32] != NULL; tmp2int32++) \
{ \
if (strcmp((arr)[tmp2int32], (not)) != 0) \
{ \
WRITE_STRING(fp, (arr)[tmp2int32]); \
} \
}
/* READ macros, used for reading data, on read error they will
call the ERROR_OUT_READERROR or ERROR_OUT_BUFERROR macro
these macros may require the availability of the following
variables:
int32_t tmpint32; - temporary variable
*/
#define READ(fp, ptr, size) \
if (tio_read(fp, ptr, (size_t)size)) \
{ \
DEBUG_PRINT("READ : var="__STRING(ptr)" error: %s", \
strerror(errno)); \
ERROR_OUT_READERROR(fp); \
} \
DEBUG_PRINT("READ : var="__STRING(ptr)" size=%d", (int)(size)); \
DEBUG_DUMP(ptr, size);
#define READ_INT32(fp, i) \
READ(fp, &tmpint32, sizeof(int32_t)); \
(i) = (int32_t)ntohl(tmpint32); \
DEBUG_PRINT("READ_INT32 : var="__STRING(i)" int32==%08x", (int)(i));
/* read a string in a fixed-size "normal" buffer */
#define READ_STRING(fp, buffer) \
/* read the size of the string */ \
READ(fp, &tmpint32, sizeof(int32_t)); \
tmpint32 = ntohl(tmpint32); \
DEBUG_PRINT("READ_STRING: var="__STRING(buffer)" strlen=%d", tmpint32); \
/* check if read would fit */ \
if (((size_t)tmpint32) >= sizeof(buffer)) \
{ \
/* will not fit */ \
tmpint32 = (tmpint32 - sizeof(buffer)) + 1; \
DEBUG_PRINT("READ : buffer %d bytes too small", tmpint32); \
ERROR_OUT_BUFERROR(fp); \
} \
/* read string from the stream */ \
if (tmpint32 > 0) \
{ \
READ(fp, buffer, (size_t)tmpint32); \
} \
/* null-terminate string in buffer */ \
buffer[tmpint32] = '\0'; \
DEBUG_PRINT("READ_STRING: var="__STRING(buffer)" string=\"%s\"", buffer);
/* READ BUF macros that read data into a pre-allocated buffer.
these macros may require the availability of the following
variables:
int32_t tmpint32; - temporary variable
char *buffer; - pointer to a buffer for reading strings
size_t buflen; - the size of the buffer
size_t bufptr; - the current position in the buffer
*/
/* current position in the buffer */
#define BUF_CUR \
(buffer + bufptr)
/* check that the buffer has sz bytes left in it */
#define BUF_CHECK(fp, sz) \
if ((bufptr + (size_t)(sz)) > buflen) \
{ \
/* will not fit */ \
tmpint32 = bufptr + (sz) - (buflen); \
DEBUG_PRINT("READ : buffer %d bytes too small", tmpint32); \
ERROR_OUT_BUFERROR(fp); \
}
/* move the buffer pointer */
#define BUF_SKIP(sz) \
bufptr += (size_t)(sz);
/* move BUF_CUR foreward so that it is aligned to the specified
type width */
#define BUF_ALIGN(fp, type) \
/* figure out number of bytes to skip foreward */ \
tmp2int32 = (sizeof(type) - ((BUF_CUR - (char *)NULL) % sizeof(type))) \
% sizeof(type); \
/* check and skip */ \
BUF_CHECK(fp, tmp2int32); \
BUF_SKIP(tmp2int32);
/* allocate a piece of the buffer to store an array in */
#define BUF_ALLOC(fp, ptr, type, num) \
/* align to the specified type width */ \
BUF_ALIGN(fp, type); \
/* check that we have enough room */ \
BUF_CHECK(fp, (size_t)(num) * sizeof(type)); \
/* store the pointer */ \
(ptr) = (type *)BUF_CUR; \
/* reserve the space */ \
BUF_SKIP((size_t)(num) * sizeof(type));
/* read a binary blob into the buffer */
#define READ_BUF(fp, ptr, sz) \
/* check that there is enough room and read */ \
BUF_CHECK(fp, sz); \
READ(fp, BUF_CUR, (size_t)sz); \
/* store pointer and skip */ \
(ptr) = BUF_CUR; \
BUF_SKIP(sz);
/* read string in the buffer (using buffer, buflen and bufptr)
and store the actual location of the string in field */
#define READ_BUF_STRING(fp, field) \
/* read the size of the string */ \
READ(fp, &tmpint32, sizeof(int32_t)); \
tmpint32 = ntohl(tmpint32); \
DEBUG_PRINT("READ_BUF_STRING: var="__STRING(field)" strlen=%d", tmpint32); \
/* check if read would fit */ \
BUF_CHECK(fp, tmpint32 + 1); \
/* read string from the stream */ \
if (tmpint32 > 0) \
{ \
READ(fp, BUF_CUR, (size_t)tmpint32); \
} \
/* null-terminate string in buffer */ \
BUF_CUR[tmpint32] = '\0'; \
DEBUG_PRINT("READ_BUF_STRING: var="__STRING(field)" string=\"%s\"", BUF_CUR); \
/* prepare result */ \
(field) = BUF_CUR; \
BUF_SKIP(tmpint32 + 1);
/* read an array from a stram and store it as a null-terminated
array list (size for the array is allocated) */
#define READ_BUF_STRINGLIST(fp, arr) \
/* read the number of entries */ \
READ(fp, &tmp3int32, sizeof(int32_t)); \
tmp3int32 = ntohl(tmp3int32); \
DEBUG_PRINT("READ_STRLST: var="__STRING(arr)" num=%d", (int)tmp3int32); \
/* allocate room for *char[num + 1] */ \
BUF_ALLOC(fp, arr, char *, tmp3int32 + 1); \
/* read all entries */ \
for (tmp2int32 = 0; tmp2int32 < tmp3int32; tmp2int32++) \
{ \
READ_BUF_STRING(fp, (arr)[tmp2int32]); \
} \
/* set last entry to NULL */ \
(arr)[tmp2int32] = NULL;
/* SKIP macros for skipping over certain parts of the protocol stream. */
/* skip a number of bytes foreward */
#define SKIP(fp, sz) \
DEBUG_PRINT("READ : skip %d bytes", (int)(sz)); \
/* read (skip) the specified number of bytes */ \
if (tio_skip(fp, sz)) \
{ \
DEBUG_PRINT("READ : skip error: %s", strerror(errno)); \
ERROR_OUT_READERROR(fp); \
}
/* read a string from the stream but don't do anything with the result */
#define SKIP_STRING(fp) \
/* read the size of the string */ \
READ(fp, &tmpint32, sizeof(int32_t)); \
tmpint32 = ntohl(tmpint32); \
DEBUG_PRINT("READ_STRING: skip %d bytes", (int)tmpint32); \
/* read (skip) the specified number of bytes */ \
SKIP(fp, tmpint32);
/* skip a list of strings */
#define SKIP_STRINGLIST(fp) \
/* read the number of entries */ \
READ(fp, &tmp3int32, sizeof(int32_t)); \
tmp3int32 = ntohl(tmp3int32); \
DEBUG_PRINT("READ_STRLST: skip %d strings", (int)tmp3int32); \
/* read all entries */ \
for (tmp2int32 = 0; tmp2int32 < tmp3int32; tmp2int32++) \
{ \
SKIP_STRING(fp); \
}
/* These are functions and macors for performing common operations in
the nslcd request/response protocol. */
/* returns a socket to the server or NULL on error (see errno),
socket should be closed with tio_close() */
TFILE *nslcd_client_open(void)
MUST_USE;
/* generic request code */
#define NSLCD_REQUEST(fp, action, writefn) \
/* open a client socket */ \
if ((fp = nslcd_client_open()) == NULL) \
{ \
ERROR_OUT_OPENERROR; \
} \
/* write a request header with a request code */ \
WRITE_INT32(fp, (int32_t)NSLCD_VERSION) \
WRITE_INT32(fp, (int32_t)action) \
/* write the request parameters (if any) */ \
writefn; \
/* flush the stream */ \
if (tio_flush(fp) < 0) \
{ \
DEBUG_PRINT("WRITE_FLUSH : error: %s", strerror(errno)); \
ERROR_OUT_WRITEERROR(fp); \
} \
/* read and check response version number */ \
READ(fp, &tmpint32, sizeof(int32_t)); \
tmpint32 = ntohl(tmpint32); \
if (tmpint32 != (int32_t)NSLCD_VERSION) \
{ \
ERROR_OUT_READERROR(fp); \
} \
/* read and check response request number */ \
READ(fp, &tmpint32, sizeof(int32_t)); \
tmpint32 = ntohl(tmpint32); \
if (tmpint32 != (int32_t)(action)) \
{ \
ERROR_OUT_READERROR(fp); \
}
/* Read the response code (the result code of the query) from
the stream. */
#define READ_RESPONSE_CODE(fp) \
READ(fp, &tmpint32, sizeof(int32_t)); \
tmpint32 = ntohl(tmpint32); \
if (tmpint32 != (int32_t)NSLCD_RESULT_BEGIN) \
{ \
ERROR_OUT_NOSUCCESS(fp); \
}
#endif /* not COMMON__NSLCD_PROT_H */