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/* iobuf.c - File Handling for OpenPGP.
* Copyright (C) 1998, 1999, 2000, 2001, 2003, 2004, 2006, 2007, 2008,
* 2009, 2010, 2011 Free Software Foundation, Inc.
* Copyright (C) 2015 g10 Code GmbH
*
* This file is part of GnuPG.
*
* This file is free software; you can redistribute it and/or modify
* it under the terms of either
*
* - the GNU Lesser General Public License as published by the Free
* Software Foundation; either version 3 of the License, or (at
* your option) any later version.
*
* or
*
* - the GNU General Public License as published by the Free
* Software Foundation; either version 2 of the License, or (at
* your option) any later version.
*
* or both in parallel, as here.
*
* This file 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see <http://www.gnu.org/licenses/>.
*/
#include <config.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <ctype.h>
#include <assert.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#ifdef HAVE_W32_SYSTEM
# ifdef HAVE_WINSOCK2_H
# include <winsock2.h>
# endif
# include <windows.h>
#endif
#ifdef __riscos__
# include <kernel.h>
# include <swis.h>
#endif /* __riscos__ */
#include <assuan.h>
#include "util.h"
#include "sysutils.h"
#include "iobuf.h"
/*-- Begin configurable part. --*/
/* The size of the internal buffers.
NOTE: If you change this value you MUST also adjust the regression
test "armored_key_8192" in armor.test! */
#define IOBUF_BUFFER_SIZE 8192
/* To avoid a potential DoS with compression packets we better limit
the number of filters in a chain. */
#define MAX_NESTING_FILTER 64
/*-- End configurable part. --*/
#ifdef HAVE_W32_SYSTEM
# ifdef HAVE_W32CE_SYSTEM
# define FD_FOR_STDIN (es_fileno (es_stdin))
# define FD_FOR_STDOUT (es_fileno (es_stdout))
# else
# define FD_FOR_STDIN (GetStdHandle (STD_INPUT_HANDLE))
# define FD_FOR_STDOUT (GetStdHandle (STD_OUTPUT_HANDLE))
# endif
#else /*!HAVE_W32_SYSTEM*/
# define FD_FOR_STDIN (0)
# define FD_FOR_STDOUT (1)
#endif /*!HAVE_W32_SYSTEM*/
/* The context used by the file filter. */
typedef struct
{
gnupg_fd_t fp; /* Open file pointer or handle. */
int keep_open;
int no_cache;
int eof_seen;
int print_only_name; /* Flags indicating that fname is not a real file. */
char fname[1]; /* Name of the file. */
} file_filter_ctx_t;
/* The context used by the estream filter. */
typedef struct
{
estream_t fp; /* Open estream handle. */
int keep_open;
int no_cache;
int eof_seen;
int print_only_name; /* Flags indicating that fname is not a real file. */
char fname[1]; /* Name of the file. */
} file_es_filter_ctx_t;
/* Object to control the "close cache". */
struct close_cache_s
{
struct close_cache_s *next;
gnupg_fd_t fp;
char fname[1];
};
typedef struct close_cache_s *close_cache_t;
static close_cache_t close_cache;
#ifdef HAVE_W32_SYSTEM
typedef struct
{
int sock;
int keep_open;
int no_cache;
int eof_seen;
int print_only_name; /* Flag indicating that fname is not a real file. */
char fname[1]; /* Name of the file */
} sock_filter_ctx_t;
#endif /*HAVE_W32_SYSTEM*/
/* The first partial length header block must be of size 512
* to make it easier (and efficienter) we use a min. block size of 512
* for all chunks (but the last one) */
#define OP_MIN_PARTIAL_CHUNK 512
#define OP_MIN_PARTIAL_CHUNK_2POW 9
/* The context we use for the block filter (used to handle OpenPGP
length information header). */
typedef struct
{
int use;
size_t size;
size_t count;
int partial; /* 1 = partial header, 2 in last partial packet. */
char *buffer; /* Used for partial header. */
size_t buflen; /* Used size of buffer. */
int first_c; /* First character of a partial header (which is > 0). */
int eof;
}
block_filter_ctx_t;
/* Global flag to tell whether special file names are enabled. See
gpg.c for an explanation of these file names. FIXME: it does not
belong into the iobuf subsystem. */
static int special_names_enabled;
/* Local prototypes. */
static int underflow (iobuf_t a);
static int translate_file_handle (int fd, int for_write);
/* This is a replacement for strcmp. Under W32 it does not
distinguish between backslash and slash. */
static int
fd_cache_strcmp (const char *a, const char *b)
{
#ifdef HAVE_DOSISH_SYSTEM
for (; *a && *b; a++, b++)
{
if (*a != *b && !((*a == '/' && *b == '\\')
|| (*a == '\\' && *b == '/')) )
break;
}
return *(const unsigned char *)a - *(const unsigned char *)b;
#else
return strcmp (a, b);
#endif
}
/*
* Invalidate (i.e. close) a cached iobuf
*/
static int
fd_cache_invalidate (const char *fname)
{
close_cache_t cc;
int rc = 0;
assert (fname);
if (DBG_IOBUF)
log_debug ("fd_cache_invalidate (%s)\n", fname);
for (cc = close_cache; cc; cc = cc->next)
{
if (cc->fp != GNUPG_INVALID_FD && !fd_cache_strcmp (cc->fname, fname))
{
if (DBG_IOBUF)
log_debug (" did (%s)\n", cc->fname);
#ifdef HAVE_W32_SYSTEM
if (!CloseHandle (cc->fp))
rc = -1;
#else
rc = close (cc->fp);
#endif
cc->fp = GNUPG_INVALID_FD;
}
}
return rc;
}
/* Try to sync changes to the disk. This is to avoid data loss during
a system crash in write/close/rename cycle on some file
systems. */
static int
fd_cache_synchronize (const char *fname)
{
int err = 0;
#ifdef HAVE_FSYNC
close_cache_t cc;
if (DBG_IOBUF)
log_debug ("fd_cache_synchronize (%s)\n", fname);
for (cc=close_cache; cc; cc = cc->next )
{
if (cc->fp != GNUPG_INVALID_FD && !fd_cache_strcmp (cc->fname, fname))
{
if (DBG_IOBUF)
log_debug (" did (%s)\n", cc->fname);
err = fsync (cc->fp);
}
}
#else
(void)fname;
#endif /*HAVE_FSYNC*/
return err;
}
static gnupg_fd_t
direct_open (const char *fname, const char *mode, int mode700)
{
#ifdef HAVE_W32_SYSTEM
unsigned long da, cd, sm;
HANDLE hfile;
/* Note, that we do not handle all mode combinations */
/* According to the ReactOS source it seems that open() of the
* standard MSW32 crt does open the file in shared mode which is
* something new for MS applications ;-)
*/
if (strchr (mode, '+'))
{
if (fd_cache_invalidate (fname))
return GNUPG_INVALID_FD;
da = GENERIC_READ | GENERIC_WRITE;
cd = OPEN_EXISTING;
sm = FILE_SHARE_READ | FILE_SHARE_WRITE;
}
else if (strchr (mode, 'w'))
{
if (fd_cache_invalidate (fname))
return GNUPG_INVALID_FD;
da = GENERIC_WRITE;
cd = CREATE_ALWAYS;
sm = FILE_SHARE_WRITE;
}
else
{
da = GENERIC_READ;
cd = OPEN_EXISTING;
sm = FILE_SHARE_READ;
}
#ifdef HAVE_W32CE_SYSTEM
{
wchar_t *wfname = utf8_to_wchar (fname);
if (wfname)
{
hfile = CreateFile (wfname, da, sm, NULL, cd,
FILE_ATTRIBUTE_NORMAL, NULL);
xfree (wfname);
}
else
hfile = INVALID_HANDLE_VALUE;
}
#else
hfile = CreateFile (fname, da, sm, NULL, cd, FILE_ATTRIBUTE_NORMAL, NULL);
#endif
return hfile;
#else /*!HAVE_W32_SYSTEM*/
int oflag;
int cflag = S_IRUSR | S_IWUSR;
if (!mode700)
cflag |= S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH;
/* Note, that we do not handle all mode combinations */
if (strchr (mode, '+'))
{
if (fd_cache_invalidate (fname))
return GNUPG_INVALID_FD;
oflag = O_RDWR;
}
else if (strchr (mode, 'w'))
{
if (fd_cache_invalidate (fname))
return GNUPG_INVALID_FD;
oflag = O_WRONLY | O_CREAT | O_TRUNC;
}
else
{
oflag = O_RDONLY;
}
#ifdef O_BINARY
if (strchr (mode, 'b'))
oflag |= O_BINARY;
#endif
#ifdef __riscos__
{
struct stat buf;
/* Don't allow iobufs on directories */
if (!stat (fname, &buf) && S_ISDIR (buf.st_mode) && !S_ISREG (buf.st_mode))
return __set_errno (EISDIR);
}
#endif
return open (fname, oflag, cflag);
#endif /*!HAVE_W32_SYSTEM*/
}
/*
* Instead of closing an FD we keep it open and cache it for later reuse
* Note that this caching strategy only works if the process does not chdir.
*/
static void
fd_cache_close (const char *fname, gnupg_fd_t fp)
{
close_cache_t cc;
assert (fp);
if (!fname || !*fname)
{
#ifdef HAVE_W32_SYSTEM
CloseHandle (fp);
#else
close (fp);
#endif
if (DBG_IOBUF)
log_debug ("fd_cache_close (%d) real\n", (int)fp);
return;
}
/* try to reuse a slot */
for (cc = close_cache; cc; cc = cc->next)
{
if (cc->fp == GNUPG_INVALID_FD && !fd_cache_strcmp (cc->fname, fname))
{
cc->fp = fp;
if (DBG_IOBUF)
log_debug ("fd_cache_close (%s) used existing slot\n", fname);
return;
}
}
/* add a new one */
if (DBG_IOBUF)
log_debug ("fd_cache_close (%s) new slot created\n", fname);
cc = xcalloc (1, sizeof *cc + strlen (fname));
strcpy (cc->fname, fname);
cc->fp = fp;
cc->next = close_cache;
close_cache = cc;
}
/*
* Do an direct_open on FNAME but first try to reuse one from the fd_cache
*/
static gnupg_fd_t
fd_cache_open (const char *fname, const char *mode)
{
close_cache_t cc;
assert (fname);
for (cc = close_cache; cc; cc = cc->next)
{
if (cc->fp != GNUPG_INVALID_FD && !fd_cache_strcmp (cc->fname, fname))
{
gnupg_fd_t fp = cc->fp;
cc->fp = GNUPG_INVALID_FD;
if (DBG_IOBUF)
log_debug ("fd_cache_open (%s) using cached fp\n", fname);
#ifdef HAVE_W32_SYSTEM
if (SetFilePointer (fp, 0, NULL, FILE_BEGIN) == 0xffffffff)
{
log_error ("rewind file failed on handle %p: ec=%d\n",
fp, (int) GetLastError ());
fp = GNUPG_INVALID_FD;
}
#else
if (lseek (fp, 0, SEEK_SET) == (off_t) - 1)
{
log_error ("can't rewind fd %d: %s\n", fp, strerror (errno));
fp = GNUPG_INVALID_FD;
}
#endif
return fp;
}
}
if (DBG_IOBUF)
log_debug ("fd_cache_open (%s) not cached\n", fname);
return direct_open (fname, mode, 0);
}
/****************
* Read data from a file into buf which has an allocated length of *LEN.
* return the number of read bytes in *LEN. OPAQUE is the FILE * of
* the stream. A is not used.
* control may be:
* IOBUFCTRL_INIT: called just before the function is linked into the
* list of function. This can be used to prepare internal
* data structures of the function.
* IOBUFCTRL_FREE: called just before the function is removed from the
* list of functions and can be used to release internal
* data structures or close a file etc.
* IOBUFCTRL_UNDERFLOW: called by iobuf_underflow to fill the buffer
* with new stuff. *RET_LEN is the available size of the
* buffer, and should be set to the number of bytes
* which were put into the buffer. The function
* returns 0 to indicate success, -1 on EOF and
* GPG_ERR_xxxxx for other errors.
*
* IOBUFCTRL_FLUSH: called by iobuf_flush() to write out the collected stuff.
* *RET_LAN is the number of bytes in BUF.
*
* IOBUFCTRL_CANCEL: send to all filters on behalf of iobuf_cancel. The
* filter may take appropriate action on this message.
*/
static int
file_filter (void *opaque, int control, iobuf_t chain, byte * buf,
size_t * ret_len)
{
file_filter_ctx_t *a = opaque;
gnupg_fd_t f = a->fp;
size_t size = *ret_len;
size_t nbytes = 0;
int rc = 0;
(void)chain; /* Not used. */
if (control == IOBUFCTRL_UNDERFLOW)
{
assert (size); /* We need a buffer. */
if (a->eof_seen)
{
rc = -1;
*ret_len = 0;
}
else
{
#ifdef HAVE_W32_SYSTEM
unsigned long nread;
nbytes = 0;
if (!ReadFile (f, buf, size, &nread, NULL))
{
int ec = (int) GetLastError ();
if (ec != ERROR_BROKEN_PIPE)
{
rc = gpg_error_from_errno (ec);
log_error ("%s: read error: ec=%d\n", a->fname, ec);
}
}
else if (!nread)
{
a->eof_seen = 1;
rc = -1;
}
else
{
nbytes = nread;
}
#else
int n;
nbytes = 0;
do
{
n = read (f, buf, size);
}
while (n == -1 && errno == EINTR);
if (n == -1)
{ /* error */
if (errno != EPIPE)
{
rc = gpg_error_from_syserror ();
log_error ("%s: read error: %s\n",
a->fname, strerror (errno));
}
}
else if (!n)
{ /* eof */
a->eof_seen = 1;
rc = -1;
}
else
{
nbytes = n;
}
#endif
*ret_len = nbytes;
}
}
else if (control == IOBUFCTRL_FLUSH)
{
if (size)
{
#ifdef HAVE_W32_SYSTEM
byte *p = buf;
unsigned long n;
nbytes = size;
do
{
if (size && !WriteFile (f, p, nbytes, &n, NULL))
{
int ec = (int) GetLastError ();
rc = gpg_error_from_errno (ec);
log_error ("%s: write error: ec=%d\n", a->fname, ec);
break;
}
p += n;
nbytes -= n;
}
while (nbytes);
nbytes = p - buf;
#else
byte *p = buf;
int n;
nbytes = size;
do
{
do
{
n = write (f, p, nbytes);
}
while (n == -1 && errno == EINTR);
if (n > 0)
{
p += n;
nbytes -= n;
}
}
while (n != -1 && nbytes);
if (n == -1)
{
rc = gpg_error_from_syserror ();
log_error ("%s: write error: %s\n", a->fname, strerror (errno));
}
nbytes = p - buf;
#endif
}
*ret_len = nbytes;
}
else if (control == IOBUFCTRL_INIT)
{
a->eof_seen = 0;
a->keep_open = 0;
a->no_cache = 0;
}
else if (control == IOBUFCTRL_DESC)
{
*(char **) buf = "file_filter(fd)";
}
else if (control == IOBUFCTRL_FREE)
{
if (f != FD_FOR_STDIN && f != FD_FOR_STDOUT)
{
if (DBG_IOBUF)
log_debug ("%s: close fd/handle %d\n", a->fname, FD2INT (f));
if (!a->keep_open)
fd_cache_close (a->no_cache ? NULL : a->fname, f);
}
f = GNUPG_INVALID_FD;
xfree (a); /* We can free our context now. */
}
return rc;
}
/* Similar to file_filter but using the estream system. */
static int
file_es_filter (void *opaque, int control, iobuf_t chain, byte * buf,
size_t * ret_len)
{
file_es_filter_ctx_t *a = opaque;
estream_t f = a->fp;
size_t size = *ret_len;
size_t nbytes = 0;
int rc = 0;
(void)chain; /* Not used. */
if (control == IOBUFCTRL_UNDERFLOW)
{
assert (size); /* We need a buffer. */
if (a->eof_seen)
{
rc = -1;
*ret_len = 0;
}
else
{
nbytes = 0;
rc = es_read (f, buf, size, &nbytes);
if (rc == -1)
{ /* error */
rc = gpg_error_from_syserror ();
log_error ("%s: read error: %s\n", a->fname, strerror (errno));
}
else if (!nbytes)
{ /* eof */
a->eof_seen = 1;
rc = -1;
}
*ret_len = nbytes;
}
}
else if (control == IOBUFCTRL_FLUSH)
{
if (size)
{
byte *p = buf;
size_t nwritten;
nbytes = size;
do
{
nwritten = 0;
if (es_write (f, p, nbytes, &nwritten))
{
rc = gpg_error_from_syserror ();
log_error ("%s: write error: %s\n",
a->fname, strerror (errno));
break;
}
p += nwritten;
nbytes -= nwritten;
}
while (nbytes);
nbytes = p - buf;
}
*ret_len = nbytes;
}
else if (control == IOBUFCTRL_INIT)
{
a->eof_seen = 0;
a->no_cache = 0;
}
else if (control == IOBUFCTRL_DESC)
{
*(char **) buf = "estream_filter";
}
else if (control == IOBUFCTRL_FREE)
{
if (f != es_stdin && f != es_stdout)
{
if (DBG_IOBUF)
log_debug ("%s: es_fclose %p\n", a->fname, f);
if (!a->keep_open)
es_fclose (f);
}
f = NULL;
xfree (a); /* We can free our context now. */
}
return rc;
}
#ifdef HAVE_W32_SYSTEM
/* Because network sockets are special objects under Lose32 we have to
use a dedicated filter for them. */
static int
sock_filter (void *opaque, int control, iobuf_t chain, byte * buf,
size_t * ret_len)
{
sock_filter_ctx_t *a = opaque;
size_t size = *ret_len;
size_t nbytes = 0;
int rc = 0;
(void)chain;
if (control == IOBUFCTRL_UNDERFLOW)
{
assert (size); /* need a buffer */
if (a->eof_seen)
{
rc = -1;
*ret_len = 0;
}
else
{
int nread;
nread = recv (a->sock, buf, size, 0);
if (nread == SOCKET_ERROR)
{
int ec = (int) WSAGetLastError ();
rc = gpg_error_from_errno (ec);
log_error ("socket read error: ec=%d\n", ec);
}
else if (!nread)
{
a->eof_seen = 1;
rc = -1;
}
else
{
nbytes = nread;
}
*ret_len = nbytes;
}
}
else if (control == IOBUFCTRL_FLUSH)
{
if (size)
{
byte *p = buf;
int n;
nbytes = size;
do
{
n = send (a->sock, p, nbytes, 0);
if (n == SOCKET_ERROR)
{
int ec = (int) WSAGetLastError ();
rc = gpg_error_from_errno (ec);
log_error ("socket write error: ec=%d\n", ec);
break;
}
p += n;
nbytes -= n;
}
while (nbytes);
nbytes = p - buf;
}
*ret_len = nbytes;
}
else if (control == IOBUFCTRL_INIT)
{
a->eof_seen = 0;
a->keep_open = 0;
a->no_cache = 0;
}
else if (control == IOBUFCTRL_DESC)
{
*(char **) buf = "sock_filter";
}
else if (control == IOBUFCTRL_FREE)
{
if (!a->keep_open)
closesocket (a->sock);
xfree (a); /* we can free our context now */
}
return rc;
}
#endif /*HAVE_W32_SYSTEM*/
/****************
* This is used to implement the block write mode.
* Block reading is done on a byte by byte basis in readbyte(),
* without a filter
*/
static int
block_filter (void *opaque, int control, iobuf_t chain, byte * buffer,
size_t * ret_len)
{
block_filter_ctx_t *a = opaque;
char *buf = (char *)buffer;
size_t size = *ret_len;
int c, needed, rc = 0;
char *p;
if (control == IOBUFCTRL_UNDERFLOW)
{
size_t n = 0;
p = buf;
assert (size); /* need a buffer */
if (a->eof) /* don't read any further */
rc = -1;
while (!rc && size)
{
if (!a->size)
{ /* get the length bytes */
if (a->partial == 2)
{
a->eof = 1;
if (!n)
rc = -1;
break;
}
else if (a->partial)
{
/* These OpenPGP introduced huffman like encoded length
* bytes are really a mess :-( */
if (a->first_c)
{
c = a->first_c;
a->first_c = 0;
}
else if ((c = iobuf_get (chain)) == -1)
{
log_error ("block_filter: 1st length byte missing\n");
rc = GPG_ERR_BAD_DATA;
break;
}
if (c < 192)
{
a->size = c;
a->partial = 2;
if (!a->size)
{
a->eof = 1;
if (!n)
rc = -1;
break;
}
}
else if (c < 224)
{
a->size = (c - 192) * 256;
if ((c = iobuf_get (chain)) == -1)
{
log_error
("block_filter: 2nd length byte missing\n");
rc = GPG_ERR_BAD_DATA;
break;
}
a->size += c + 192;
a->partial = 2;
if (!a->size)
{
a->eof = 1;
if (!n)
rc = -1;
break;
}
}
else if (c == 255)
{
a->size = (size_t)iobuf_get (chain) << 24;
a->size |= iobuf_get (chain) << 16;
a->size |= iobuf_get (chain) << 8;
if ((c = iobuf_get (chain)) == -1)
{
log_error ("block_filter: invalid 4 byte length\n");
rc = GPG_ERR_BAD_DATA;
break;
}
a->size |= c;
a->partial = 2;
if (!a->size)
{
a->eof = 1;
if (!n)
rc = -1;
break;
}
}
else
{ /* Next partial body length. */
a->size = 1 << (c & 0x1f);
}
/* log_debug("partial: ctx=%p c=%02x size=%u\n", a, c, a->size); */
}
else
BUG ();
}
while (!rc && size && a->size)
{
needed = size < a->size ? size : a->size;
c = iobuf_read (chain, p, needed);
if (c < needed)
{
if (c == -1)
c = 0;
log_error
("block_filter %p: read error (size=%lu,a->size=%lu)\n",
a, (ulong) size + c, (ulong) a->size + c);
rc = GPG_ERR_BAD_DATA;
}
else
{
size -= c;
a->size -= c;
p += c;
n += c;
}
}
}
*ret_len = n;
}
else if (control == IOBUFCTRL_FLUSH)
{
if (a->partial)
{ /* the complicated openpgp scheme */
size_t blen, n, nbytes = size + a->buflen;
assert (a->buflen <= OP_MIN_PARTIAL_CHUNK);
if (nbytes < OP_MIN_PARTIAL_CHUNK)
{
/* not enough to write a partial block out; so we store it */
if (!a->buffer)
a->buffer = xmalloc (OP_MIN_PARTIAL_CHUNK);
memcpy (a->buffer + a->buflen, buf, size);
a->buflen += size;
}
else
{ /* okay, we can write out something */
/* do this in a loop to use the most efficient block lengths */
p = buf;
do
{
/* find the best matching block length - this is limited
* by the size of the internal buffering */
for (blen = OP_MIN_PARTIAL_CHUNK * 2,
c = OP_MIN_PARTIAL_CHUNK_2POW + 1; blen <= nbytes;
blen *= 2, c++)
;
blen /= 2;
c--;
/* write the partial length header */
assert (c <= 0x1f); /*;-) */
c |= 0xe0;
iobuf_put (chain, c);
if ((n = a->buflen))
{ /* write stuff from the buffer */
assert (n == OP_MIN_PARTIAL_CHUNK);
if (iobuf_write (chain, a->buffer, n))
rc = gpg_error_from_syserror ();
a->buflen = 0;
nbytes -= n;
}
if ((n = nbytes) > blen)
n = blen;
if (n && iobuf_write (chain, p, n))
rc = gpg_error_from_syserror ();
p += n;
nbytes -= n;
}
while (!rc && nbytes >= OP_MIN_PARTIAL_CHUNK);
/* store the rest in the buffer */
if (!rc && nbytes)
{
assert (!a->buflen);
assert (nbytes < OP_MIN_PARTIAL_CHUNK);
if (!a->buffer)
a->buffer = xmalloc (OP_MIN_PARTIAL_CHUNK);
memcpy (a->buffer, p, nbytes);
a->buflen = nbytes;
}
}
}
else
BUG ();
}
else if (control == IOBUFCTRL_INIT)
{
if (DBG_IOBUF)
log_debug ("init block_filter %p\n", a);
if (a->partial)
a->count = 0;
else if (a->use == IOBUF_INPUT)
a->count = a->size = 0;
else
a->count = a->size; /* force first length bytes */
a->eof = 0;
a->buffer = NULL;
a->buflen = 0;
}
else if (control == IOBUFCTRL_DESC)
{
*(char **) buf = "block_filter";
}
else if (control == IOBUFCTRL_FREE)
{
if (a->use == IOBUF_OUTPUT)
{ /* write the end markers */
if (a->partial)
{
u32 len;
/* write out the remaining bytes without a partial header
* the length of this header may be 0 - but if it is
* the first block we are not allowed to use a partial header
* and frankly we can't do so, because this length must be
* a power of 2. This is _really_ complicated because we
* have to check the possible length of a packet prior
* to it's creation: a chain of filters becomes complicated
* and we need a lot of code to handle compressed packets etc.
* :-(((((((
*/
/* construct header */
len = a->buflen;
/*log_debug("partial: remaining length=%u\n", len ); */
if (len < 192)
rc = iobuf_put (chain, len);
else if (len < 8384)
{
if (!(rc = iobuf_put (chain, ((len - 192) / 256) + 192)))
rc = iobuf_put (chain, ((len - 192) % 256));
}
else
{ /* use a 4 byte header */
if (!(rc = iobuf_put (chain, 0xff)))
if (!(rc = iobuf_put (chain, (len >> 24) & 0xff)))
if (!(rc = iobuf_put (chain, (len >> 16) & 0xff)))
if (!(rc = iobuf_put (chain, (len >> 8) & 0xff)))
rc = iobuf_put (chain, len & 0xff);
}
if (!rc && len)
rc = iobuf_write (chain, a->buffer, len);
if (rc)
{
log_error ("block_filter: write error: %s\n",
strerror (errno));
rc = gpg_error_from_syserror ();
}
xfree (a->buffer);
a->buffer = NULL;
a->buflen = 0;
}
else
BUG ();
}
else if (a->size)
{
log_error ("block_filter: pending bytes!\n");
}
if (DBG_IOBUF)
log_debug ("free block_filter %p\n", a);
xfree (a); /* we can free our context now */
}
return rc;
}
static const char *
iobuf_desc (iobuf_t a)
{
size_t dummy_len = 0;
const char *desc = "?";
if (! a || ! a->filter)
return desc;
a->filter (a->filter_ov, IOBUFCTRL_DESC, NULL,
(byte *) & desc, &dummy_len);
return desc;
}
static void
print_chain (iobuf_t a)
{
if (!DBG_IOBUF)
return;
for (; a; a = a->chain)
{
log_debug ("iobuf chain: %d.%d '%s' filter_eof=%d start=%d len=%d\n",
a->no, a->subno, iobuf_desc (a), a->filter_eof,
(int) a->d.start, (int) a->d.len);
}
}
int
iobuf_print_chain (iobuf_t a)
{
print_chain (a);
return 0;
}
/* Allocate a new io buffer, with no function assigned.
USE is the desired usage: IOBUF_INPUT for input, IOBUF_OUTPUT for
output, or IOBUF_TEMP for a temp buffer.
BUFSIZE is a suggested buffer size.
*/
iobuf_t
iobuf_alloc (int use, size_t bufsize)
{
iobuf_t a;
static int number = 0;
assert (use == IOBUF_INPUT || use == IOBUF_OUTPUT || use == IOBUF_TEMP);
a = xcalloc (1, sizeof *a);
a->use = use;
a->d.buf = xmalloc (bufsize);
a->d.size = bufsize;
a->no = ++number;
a->subno = 0;
a->real_fname = NULL;
return a;
}
int
iobuf_close (iobuf_t a)
{
iobuf_t a2;
size_t dummy_len = 0;
int rc = 0;
for (; a && !rc; a = a2)
{
a2 = a->chain;
if (a->use == IOBUF_OUTPUT && (rc = iobuf_flush (a)))
log_error ("iobuf_flush failed on close: %s\n", gpg_strerror (rc));
if (DBG_IOBUF)
log_debug ("iobuf-%d.%d: close '%s'\n",
a->no, a->subno, iobuf_desc (a));
if (a->filter && (rc = a->filter (a->filter_ov, IOBUFCTRL_FREE,
a->chain, NULL, &dummy_len)))
log_error ("IOBUFCTRL_FREE failed on close: %s\n", gpg_strerror (rc));
xfree (a->real_fname);
if (a->d.buf)
{
memset (a->d.buf, 0, a->d.size); /* erase the buffer */
xfree (a->d.buf);
}
xfree (a);
}
return rc;
}
int
iobuf_cancel (iobuf_t a)
{
const char *s;
iobuf_t a2;
int rc;
#if defined(HAVE_W32_SYSTEM) || defined(__riscos__)
char *remove_name = NULL;
#endif
if (a && a->use == IOBUF_OUTPUT)
{
s = iobuf_get_real_fname (a);
if (s && *s)
{
#if defined(HAVE_W32_SYSTEM) || defined(__riscos__)
remove_name = xstrdup (s);
#else
remove (s);
#endif
}
}
/* send a cancel message to all filters */
for (a2 = a; a2; a2 = a2->chain)
{
size_t dummy;
if (a2->filter)
a2->filter (a2->filter_ov, IOBUFCTRL_CANCEL, a2->chain, NULL, &dummy);
}
rc = iobuf_close (a);
#if defined(HAVE_W32_SYSTEM) || defined(__riscos__)
if (remove_name)
{
/* Argg, MSDOS does not allow to remove open files. So
* we have to do it here */
#ifdef HAVE_W32CE_SYSTEM
wchar_t *wtmp = utf8_to_wchar (remove_name);
if (wtmp)
DeleteFile (wtmp);
xfree (wtmp);
#else
remove (remove_name);
#endif
xfree (remove_name);
}
#endif
return rc;
}
/****************
* create a temporary iobuf, which can be used to collect stuff
* in an iobuf and later be written by iobuf_write_temp() to another
* iobuf.
*/
iobuf_t
iobuf_temp ()
{
iobuf_t a;
a = iobuf_alloc (IOBUF_TEMP, IOBUF_BUFFER_SIZE);
return a;
}
iobuf_t
iobuf_temp_with_content (const char *buffer, size_t length)
{
iobuf_t a;
int i;
a = iobuf_alloc (IOBUF_INPUT, length);
/* memcpy (a->d.buf, buffer, length); */
for (i=0; i < length; i++)
a->d.buf[i] = buffer[i];
a->d.len = length;
return a;
}
void
iobuf_enable_special_filenames (int yes)
{
special_names_enabled = yes;
}
/* See whether the filename has the form "-&nnnn", where n is a
non-zero number. Returns this number or -1 if it is not the
case. */
static int
check_special_filename (const char *fname)
{
if (special_names_enabled && fname && *fname == '-' && fname[1] == '&')
{
int i;
fname += 2;
for (i = 0; digitp (fname+i); i++)
;
if (!fname[i])
return atoi (fname);
}
return -1;
}
/* This fucntion returns true if FNAME indicates a PIPE (stdout or
stderr) or a special file name if those are enabled. */
int
iobuf_is_pipe_filename (const char *fname)
{
if (!fname || (*fname=='-' && !fname[1]) )
return 1;
return check_special_filename (fname) != -1;
}
/* Either open the file specified by the file descriptor FD or - if FD
is -1, the file with name FNAME. As of now MODE is assumed to be
"rb" if FNAME is used. In contrast to iobuf_fdopen the file
descriptor FD will not be closed during an iobuf_close. */
iobuf_t
iobuf_open_fd_or_name (gnupg_fd_t fd, const char *fname, const char *mode)
{
iobuf_t a;
if (fd == GNUPG_INVALID_FD)
a = iobuf_open (fname);
else
a = iobuf_fdopen_nc (FD2INT(fd), mode);
return a;
}
/****************
* Create a head iobuf for reading from a file
* returns: NULL if an error occures and sets errno
*/
iobuf_t
iobuf_open (const char *fname)
{
iobuf_t a;
gnupg_fd_t fp;
file_filter_ctx_t *fcx;
size_t len = 0;
int print_only = 0;
int fd;
if (!fname || (*fname == '-' && !fname[1]))
{
fp = FD_FOR_STDIN;
fname = "[stdin]";
print_only = 1;
}
else if ((fd = check_special_filename (fname)) != -1)
return iobuf_fdopen (translate_file_handle (fd, 0), "rb");
else if ((fp = fd_cache_open (fname, "rb")) == GNUPG_INVALID_FD)
return NULL;
a = iobuf_alloc (IOBUF_INPUT, IOBUF_BUFFER_SIZE);
fcx = xmalloc (sizeof *fcx + strlen (fname));
fcx->fp = fp;
fcx->print_only_name = print_only;
strcpy (fcx->fname, fname);
if (!print_only)
a->real_fname = xstrdup (fname);
a->filter = file_filter;
a->filter_ov = fcx;
file_filter (fcx, IOBUFCTRL_INIT, NULL, NULL, &len);
if (DBG_IOBUF)
log_debug ("iobuf-%d.%d: open '%s' fd=%d\n",
a->no, a->subno, fname, FD2INT (fcx->fp));
return a;
}
static iobuf_t
do_iobuf_fdopen (int fd, const char *mode, int keep_open)
{
iobuf_t a;
gnupg_fd_t fp;
file_filter_ctx_t *fcx;
size_t len;
fp = INT2FD (fd);
a = iobuf_alloc (strchr (mode, 'w') ? IOBUF_OUTPUT : IOBUF_INPUT,
IOBUF_BUFFER_SIZE);
fcx = xmalloc (sizeof *fcx + 20);
fcx->fp = fp;
fcx->print_only_name = 1;
fcx->keep_open = keep_open;
sprintf (fcx->fname, "[fd %d]", fd);
a->filter = file_filter;
a->filter_ov = fcx;
file_filter (fcx, IOBUFCTRL_INIT, NULL, NULL, &len);
if (DBG_IOBUF)
log_debug ("iobuf-%d.%d: fdopen%s '%s'\n",
a->no, a->subno, keep_open? "_nc":"", fcx->fname);
iobuf_ioctl (a, IOBUF_IOCTL_NO_CACHE, 1, NULL);
return a;
}
/* Create a head iobuf for reading or writing from/to a file Returns:
* NULL and sets ERRNO if an error occured. */
iobuf_t
iobuf_fdopen (int fd, const char *mode)
{
return do_iobuf_fdopen (fd, mode, 0);
}
iobuf_t
iobuf_fdopen_nc (int fd, const char *mode)
{
return do_iobuf_fdopen (fd, mode, 1);
}
iobuf_t
iobuf_esopen (estream_t estream, const char *mode, int keep_open)
{
iobuf_t a;
file_es_filter_ctx_t *fcx;
size_t len;
a = iobuf_alloc (strchr (mode, 'w') ? IOBUF_OUTPUT : IOBUF_INPUT,
IOBUF_BUFFER_SIZE);
fcx = xtrymalloc (sizeof *fcx + 30);
fcx->fp = estream;
fcx->print_only_name = 1;
fcx->keep_open = keep_open;
sprintf (fcx->fname, "[fd %p]", estream);
a->filter = file_es_filter;
a->filter_ov = fcx;
file_es_filter (fcx, IOBUFCTRL_INIT, NULL, NULL, &len);
if (DBG_IOBUF)
log_debug ("iobuf-%d.%d: esopen%s '%s'\n",
a->no, a->subno, keep_open? "_nc":"", fcx->fname);
return a;
}
iobuf_t
iobuf_sockopen (int fd, const char *mode)
{
iobuf_t a;
#ifdef HAVE_W32_SYSTEM
sock_filter_ctx_t *scx;
size_t len;
a = iobuf_alloc (strchr (mode, 'w') ? IOBUF_OUTPUT : IOBUF_INPUT,
IOBUF_BUFFER_SIZE);
scx = xmalloc (sizeof *scx + 25);
scx->sock = fd;
scx->print_only_name = 1;
sprintf (scx->fname, "[sock %d]", fd);
a->filter = sock_filter;
a->filter_ov = scx;
sock_filter (scx, IOBUFCTRL_INIT, NULL, NULL, &len);
if (DBG_IOBUF)
log_debug ("iobuf-%d.%d: sockopen '%s'\n", a->no, a->subno, scx->fname);
iobuf_ioctl (a, IOBUF_IOCTL_NO_CACHE, 1, NULL);
#else
a = iobuf_fdopen (fd, mode);
#endif
return a;
}
/****************
* Create an iobuf for writing to a file; the file will be created.
* With MODE700 set the file is created with that mode (Unix only).
*/
iobuf_t
iobuf_create (const char *fname, int mode700)
{
iobuf_t a;
gnupg_fd_t fp;
file_filter_ctx_t *fcx;
size_t len;
int print_only = 0;
int fd;
if (!fname || (*fname == '-' && !fname[1]))
{
fp = FD_FOR_STDOUT;
fname = "[stdout]";
print_only = 1;
}
else if ((fd = check_special_filename (fname)) != -1)
return iobuf_fdopen (translate_file_handle (fd, 1), "wb");
else if ((fp = direct_open (fname, "wb", mode700)) == GNUPG_INVALID_FD)
return NULL;
a = iobuf_alloc (IOBUF_OUTPUT, IOBUF_BUFFER_SIZE);
fcx = xmalloc (sizeof *fcx + strlen (fname));
fcx->fp = fp;
fcx->print_only_name = print_only;
strcpy (fcx->fname, fname);
if (!print_only)
a->real_fname = xstrdup (fname);
a->filter = file_filter;
a->filter_ov = fcx;
file_filter (fcx, IOBUFCTRL_INIT, NULL, NULL, &len);
if (DBG_IOBUF)
log_debug ("iobuf-%d.%d: create '%s'\n",
a->no, a->subno, iobuf_desc (a));
return a;
}
iobuf_t
iobuf_openrw (const char *fname)
{
iobuf_t a;
gnupg_fd_t fp;
file_filter_ctx_t *fcx;
size_t len;
if (!fname)
return NULL;
else if ((fp = direct_open (fname, "r+b", 0)) == GNUPG_INVALID_FD)
return NULL;
a = iobuf_alloc (IOBUF_OUTPUT, IOBUF_BUFFER_SIZE);
fcx = xmalloc (sizeof *fcx + strlen (fname));
fcx->fp = fp;
strcpy (fcx->fname, fname);
a->real_fname = xstrdup (fname);
a->filter = file_filter;
a->filter_ov = fcx;
file_filter (fcx, IOBUFCTRL_INIT, NULL, NULL, &len);
if (DBG_IOBUF)
log_debug ("iobuf-%d.%d: openrw '%s'\n",
a->no, a->subno, iobuf_desc (a));
return a;
}
int
iobuf_ioctl (iobuf_t a, iobuf_ioctl_t cmd, int intval, void *ptrval)
{
if (cmd == IOBUF_IOCTL_KEEP_OPEN)
{
/* Keep system filepointer/descriptor open. This was used in
the past by http.c; this ioctl is not directly used
anymore. */
if (DBG_IOBUF)
log_debug ("iobuf-%d.%d: ioctl '%s' keep_open=%d\n",
a ? a->no : -1, a ? a->subno : -1, iobuf_desc (a),
intval);
for (; a; a = a->chain)
if (!a->chain && a->filter == file_filter)
{
file_filter_ctx_t *b = a->filter_ov;
b->keep_open = intval;
return 0;
}
#ifdef HAVE_W32_SYSTEM
else if (!a->chain && a->filter == sock_filter)
{
sock_filter_ctx_t *b = a->filter_ov;
b->keep_open = intval;
return 0;
}
#endif
}
else if (cmd == IOBUF_IOCTL_INVALIDATE_CACHE)
{
if (DBG_IOBUF)
log_debug ("iobuf-*.*: ioctl '%s' invalidate\n",
ptrval ? (char *) ptrval : "?");
if (!a && !intval && ptrval)
{
if (fd_cache_invalidate (ptrval))
return -1;
return 0;
}
}
else if (cmd == IOBUF_IOCTL_NO_CACHE)
{
if (DBG_IOBUF)
log_debug ("iobuf-%d.%d: ioctl '%s' no_cache=%d\n",
a ? a->no : -1, a ? a->subno : -1, iobuf_desc (a),
intval);
for (; a; a = a->chain)
if (!a->chain && a->filter == file_filter)
{
file_filter_ctx_t *b = a->filter_ov;
b->no_cache = intval;
return 0;
}
#ifdef HAVE_W32_SYSTEM
else if (!a->chain && a->filter == sock_filter)
{
sock_filter_ctx_t *b = a->filter_ov;
b->no_cache = intval;
return 0;
}
#endif
}
else if (cmd == IOBUF_IOCTL_FSYNC)
{
/* Do a fsync on the open fd and return any errors to the caller
of iobuf_ioctl. Note that we work on a file name here. */
if (DBG_IOBUF)
log_debug ("iobuf-*.*: ioctl '%s' fsync\n",
ptrval? (const char*)ptrval:"<null>");
if (!a && !intval && ptrval)
{
return fd_cache_synchronize (ptrval);
}
}
return -1;
}
/****************
* Register an i/o filter.
*/
int
iobuf_push_filter (iobuf_t a,
int (*f) (void *opaque, int control,
iobuf_t chain, byte * buf, size_t * len),
void *ov)
{
return iobuf_push_filter2 (a, f, ov, 0);
}
int
iobuf_push_filter2 (iobuf_t a,
int (*f) (void *opaque, int control,
iobuf_t chain, byte * buf, size_t * len),
void *ov, int rel_ov)
{
iobuf_t b;
size_t dummy_len = 0;
int rc = 0;
if (a->use == IOBUF_OUTPUT && (rc = iobuf_flush (a)))
return rc;
if (a->subno >= MAX_NESTING_FILTER)
{
log_error ("i/o filter too deeply nested - corrupted data?\n");
return GPG_ERR_BAD_DATA;
}
/* make a copy of the current stream, so that
* A is the new stream and B the original one.
* The contents of the buffers are transferred to the
* new stream.
*/
b = xmalloc (sizeof *b);
memcpy (b, a, sizeof *b);
/* fixme: it is stupid to keep a copy of the name at every level
* but we need the name somewhere because the name known by file_filter
* may have been released when we need the name of the file */
b->real_fname = a->real_fname ? xstrdup (a->real_fname) : NULL;
/* remove the filter stuff from the new stream */
a->filter = NULL;
a->filter_ov = NULL;
a->filter_ov_owner = 0;
a->filter_eof = 0;
if (a->use == IOBUF_TEMP)
/* make a write stream from a temp stream */
a->use = IOBUF_OUTPUT;
if (a->use == IOBUF_OUTPUT)
{ /* allocate a fresh buffer for the
original stream */
b->d.buf = xmalloc (a->d.size);
b->d.len = 0;
b->d.start = 0;
}
else
{ /* allocate a fresh buffer for the new
stream */
a->d.buf = xmalloc (a->d.size);
a->d.len = 0;
a->d.start = 0;
}
/* disable nlimit for the new stream */
a->ntotal = b->ntotal + b->nbytes;
a->nlimit = a->nbytes = 0;
a->nofast = 0;
/* make a link from the new stream to the original stream */
a->chain = b;
/* setup the function on the new stream */
a->filter = f;
a->filter_ov = ov;
a->filter_ov_owner = rel_ov;
a->subno = b->subno + 1;
if (DBG_IOBUF)
{
log_debug ("iobuf-%d.%d: push '%s'\n",
a->no, a->subno, iobuf_desc (a));
print_chain (a);
}
/* now we can initialize the new function if we have one */
if (a->filter && (rc = a->filter (a->filter_ov, IOBUFCTRL_INIT, a->chain,
NULL, &dummy_len)))
log_error ("IOBUFCTRL_INIT failed: %s\n", gpg_strerror (rc));
return rc;
}
/****************
* Remove an i/o filter.
*/
static int
pop_filter (iobuf_t a, int (*f) (void *opaque, int control,
iobuf_t chain, byte * buf, size_t * len),
void *ov)
{
iobuf_t b;
size_t dummy_len = 0;
int rc = 0;
if (DBG_IOBUF)
log_debug ("iobuf-%d.%d: pop '%s'\n",
a->no, a->subno, iobuf_desc (a));
if (!a->filter)
{ /* this is simple */
b = a->chain;
assert (b);
xfree (a->d.buf);
xfree (a->real_fname);
memcpy (a, b, sizeof *a);
xfree (b);
return 0;
}
for (b = a; b; b = b->chain)
if (b->filter == f && (!ov || b->filter_ov == ov))
break;
if (!b)
log_bug ("pop_filter(): filter function not found\n");
/* flush this stream if it is an output stream */
if (a->use == IOBUF_OUTPUT && (rc = iobuf_flush (b)))
{
log_error ("iobuf_flush failed in pop_filter: %s\n", gpg_strerror (rc));
return rc;
}
/* and tell the filter to free it self */
if (b->filter && (rc = b->filter (b->filter_ov, IOBUFCTRL_FREE, b->chain,
NULL, &dummy_len)))
{
log_error ("IOBUFCTRL_FREE failed: %s\n", gpg_strerror (rc));
return rc;
}
if (b->filter_ov && b->filter_ov_owner)
{
xfree (b->filter_ov);
b->filter_ov = NULL;
}
/* and see how to remove it */
if (a == b && !b->chain)
log_bug ("can't remove the last filter from the chain\n");
else if (a == b)
{ /* remove the first iobuf from the chain */
/* everything from b is copied to a. This is save because
* a flush has been done on the to be removed entry
*/
b = a->chain;
xfree (a->d.buf);
xfree (a->real_fname);
memcpy (a, b, sizeof *a);
xfree (b);
if (DBG_IOBUF)
log_debug ("iobuf-%d.%d: popped filter\n", a->no, a->subno);
}
else if (!b->chain)
{ /* remove the last iobuf from the chain */
log_bug ("Ohh jeee, trying to remove a head filter\n");
}
else
{ /* remove an intermediate iobuf from the chain */
log_bug ("Ohh jeee, trying to remove an intermediate filter\n");
}
return rc;
}
/****************
* read underflow: read more bytes into the buffer and return
* the first byte or -1 on EOF.
*/
static int
underflow (iobuf_t a)
{
size_t len;
int rc;
assert (a->d.start == a->d.len);
if (a->use == IOBUF_TEMP)
return -1; /* EOF because a temp buffer can't do an underflow */
if (a->filter_eof)
{
if (a->chain)
{
iobuf_t b = a->chain;
if (DBG_IOBUF)
log_debug ("iobuf-%d.%d: pop '%s' in underflow\n",
a->no, a->subno, iobuf_desc (a));
xfree (a->d.buf);
xfree (a->real_fname);
memcpy (a, b, sizeof *a);
xfree (b);
print_chain (a);
}
else
a->filter_eof = 0; /* for the top level filter */
if (DBG_IOBUF)
log_debug ("iobuf-%d.%d: underflow: eof (due to filter eof)\n",
a->no, a->subno);
return -1; /* return one(!) EOF */
}
if (a->error)
{
if (DBG_IOBUF)
log_debug ("iobuf-%d.%d: error\n", a->no, a->subno);
return -1;
}
if (a->filter)
{
len = a->d.size;
if (DBG_IOBUF)
log_debug ("iobuf-%d.%d: underflow: req=%lu\n",
a->no, a->subno, (ulong) len);
rc = a->filter (a->filter_ov, IOBUFCTRL_UNDERFLOW, a->chain,
a->d.buf, &len);
if (DBG_IOBUF)
{
log_debug ("iobuf-%d.%d: underflow: got=%lu rc=%d\n",
a->no, a->subno, (ulong) len, rc);
/* if( a->no == 1 ) */
/* log_hexdump (" data:", a->d.buf, len); */
}
if (a->use == IOBUF_INPUT && rc == -1)
{ /* EOF: we can remove the filter */
size_t dummy_len = 0;
/* and tell the filter to free itself */
if ((rc = a->filter (a->filter_ov, IOBUFCTRL_FREE, a->chain,
NULL, &dummy_len)))
log_error ("IOBUFCTRL_FREE failed: %s\n", gpg_strerror (rc));
if (a->filter_ov && a->filter_ov_owner)
{
xfree (a->filter_ov);
a->filter_ov = NULL;
}
a->filter = NULL;
a->filter_ov = NULL;
a->filter_eof = 1;
if (!len && a->chain)
{
iobuf_t b = a->chain;
if (DBG_IOBUF)
log_debug ("iobuf-%d.%d: pop in underflow (!len)\n",
a->no, a->subno);
xfree (a->d.buf);
xfree (a->real_fname);
memcpy (a, b, sizeof *a);
xfree (b);
print_chain (a);
}
}
else if (rc)
a->error = rc;
if (!len)
{
if (DBG_IOBUF)
log_debug ("iobuf-%d.%d: underflow: eof\n", a->no, a->subno);
return -1;
}
a->d.len = len;
a->d.start = 0;
return a->d.buf[a->d.start++];
}
else
{
if (DBG_IOBUF)
log_debug ("iobuf-%d.%d: underflow: eof (no filter)\n",
a->no, a->subno);
return -1; /* no filter; return EOF */
}
}
int
iobuf_flush (iobuf_t a)
{
size_t len;
int rc;
if (a->use == IOBUF_TEMP)
{ /* increase the temp buffer */
unsigned char *newbuf;
size_t newsize = a->d.size + IOBUF_BUFFER_SIZE;
if (DBG_IOBUF)
log_debug ("increasing temp iobuf from %lu to %lu\n",
(ulong) a->d.size, (ulong) newsize);
newbuf = xmalloc (newsize);
memcpy (newbuf, a->d.buf, a->d.len);
xfree (a->d.buf);
a->d.buf = newbuf;
a->d.size = newsize;
return 0;
}
else if (a->use != IOBUF_OUTPUT)
log_bug ("flush on non-output iobuf\n");
else if (!a->filter)
log_bug ("iobuf_flush: no filter\n");
len = a->d.len;
rc = a->filter (a->filter_ov, IOBUFCTRL_FLUSH, a->chain, a->d.buf, &len);
if (!rc && len != a->d.len)
{
log_info ("iobuf_flush did not write all!\n");
rc = GPG_ERR_INTERNAL;
}
else if (rc)
a->error = rc;
a->d.len = 0;
return rc;
}
/****************
* Read a byte from the iobuf; returns -1 on EOF
*/
int
iobuf_readbyte (iobuf_t a)
{
int c;
if (a->nlimit && a->nbytes >= a->nlimit)
return -1; /* forced EOF */
if (a->d.start < a->d.len)
{
c = a->d.buf[a->d.start++];
}
else if ((c = underflow (a)) == -1)
return -1; /* EOF */
a->nbytes++;
return c;
}
int
iobuf_read (iobuf_t a, void *buffer, unsigned int buflen)
{
unsigned char *buf = (unsigned char *)buffer;
int c, n;
if (a->nlimit)
{
/* Handle special cases. */
for (n = 0; n < buflen; n++)
{
if ((c = iobuf_readbyte (a)) == -1)
{
if (!n)
return -1; /* eof */
break;
}
else if (buf)
*buf = c;
if (buf)
buf++;
}
return n;
}
n = 0;
do
{
if (n < buflen && a->d.start < a->d.len)
{
unsigned size = a->d.len - a->d.start;
if (size > buflen - n)
size = buflen - n;
if (buf)
memcpy (buf, a->d.buf + a->d.start, size);
n += size;
a->d.start += size;
if (buf)
buf += size;
}
if (n < buflen)
{
if ((c = underflow (a)) == -1)
{
a->nbytes += n;
return n ? n : -1 /*EOF*/;
}
if (buf)
*buf++ = c;
n++;
}
}
while (n < buflen);
a->nbytes += n;
return n;
}
/****************
* Have a look at the iobuf.
* NOTE: This only works in special cases.
*/
int
iobuf_peek (iobuf_t a, byte * buf, unsigned buflen)
{
int n = 0;
if (a->filter_eof)
return -1;
if (!(a->d.start < a->d.len))
{
if (underflow (a) == -1)
return -1;
/* And unget this character. */
assert (a->d.start == 1);
a->d.start = 0;
}
for (n = 0; n < buflen && (a->d.start + n) < a->d.len; n++, buf++)
*buf = a->d.buf[n];
return n;
}
int
iobuf_writebyte (iobuf_t a, unsigned int c)
{
int rc;
if (a->d.len == a->d.size)
if ((rc=iobuf_flush (a)))
return rc;
assert (a->d.len < a->d.size);
a->d.buf[a->d.len++] = c;
return 0;
}
int
iobuf_write (iobuf_t a, const void *buffer, unsigned int buflen)
{
const unsigned char *buf = (const unsigned char *)buffer;
int rc;
do
{
if (buflen && a->d.len < a->d.size)
{
unsigned size = a->d.size - a->d.len;
if (size > buflen)
size = buflen;
memcpy (a->d.buf + a->d.len, buf, size);
buflen -= size;
buf += size;
a->d.len += size;
}
if (buflen)
{
rc = iobuf_flush (a);
if (rc)
return rc;
}
}
while (buflen);
return 0;
}
int
iobuf_writestr (iobuf_t a, const char *buf)
{
int rc;
for (; *buf; buf++)
if ((rc=iobuf_writebyte (a, *buf)))
return rc;
return 0;
}
/****************
* copy the contents of TEMP to A.
*/
int
iobuf_write_temp (iobuf_t a, iobuf_t temp)
{
while (temp->chain)
pop_filter (temp, temp->filter, NULL);
return iobuf_write (a, temp->d.buf, temp->d.len);
}
/****************
* copy the contents of the temp io stream to BUFFER.
*/
size_t
iobuf_temp_to_buffer (iobuf_t a, byte * buffer, size_t buflen)
{
size_t n = a->d.len;
if (n > buflen)
n = buflen;
memcpy (buffer, a->d.buf, n);
return n;
}
/****************
* Call this function to terminate processing of the temp stream
* without closing it. This removes all filters from the stream
* makes sure that iobuf_get_temp_{buffer,length}() returns correct
* values.
*/
void
iobuf_flush_temp (iobuf_t temp)
{
while (temp->chain)
pop_filter (temp, temp->filter, NULL);
}
/****************
* Set a limit on how many bytes may be read from the input stream A.
* Setting the limit to 0 disables this feature.
*/
void
iobuf_set_limit (iobuf_t a, off_t nlimit)
{
if (nlimit)
a->nofast = 1;
else
a->nofast = 0;
a->nlimit = nlimit;
a->ntotal += a->nbytes;
a->nbytes = 0;
}
/* Return the length of an open file A. IF OVERFLOW is not NULL it
will be set to true if the file is larger than what off_t can cope
with. The function return 0 on error or on overflow condition. */
off_t
iobuf_get_filelength (iobuf_t a, int *overflow)
{
struct stat st;
if (overflow)
*overflow = 0;
/* Hmmm: file_filter may have already been removed */
for ( ; a; a = a->chain )
if ( !a->chain && a->filter == file_filter )
{
file_filter_ctx_t *b = a->filter_ov;
gnupg_fd_t fp = b->fp;
#if defined(HAVE_W32_SYSTEM)
ulong size;
static int (* __stdcall get_file_size_ex) (void *handle,
LARGE_INTEGER *r_size);
static int get_file_size_ex_initialized;
if (!get_file_size_ex_initialized)
{
void *handle;
handle = dlopen ("kernel32.dll", RTLD_LAZY);
if (handle)
{
get_file_size_ex = dlsym (handle, "GetFileSizeEx");
if (!get_file_size_ex)
dlclose (handle);
}
get_file_size_ex_initialized = 1;
}
if (get_file_size_ex)
{
/* This is a newer system with GetFileSizeEx; we use this
then because it seem that GetFileSize won't return a
proper error in case a file is larger than 4GB. */
LARGE_INTEGER exsize;
if (get_file_size_ex (fp, &exsize))
{
if (!exsize.u.HighPart)
return exsize.u.LowPart;
if (overflow)
*overflow = 1;
return 0;
}
}
else
{
if ((size=GetFileSize (fp, NULL)) != 0xffffffff)
return size;
}
log_error ("GetFileSize for handle %p failed: %s\n",
fp, w32_strerror (0));
#else
if ( !fstat (FD2INT (fp), &st) )
return st.st_size;
log_error("fstat() failed: %s\n", strerror(errno) );
#endif
break/*the for loop*/;
}
return 0;
}
/* Return the file descriptor of the underlying file or -1 if it is
not available. */
int
iobuf_get_fd (iobuf_t a)
{
for ( ; a; a = a->chain )
if (!a->chain && a->filter == file_filter)
{
file_filter_ctx_t *b = a->filter_ov;
gnupg_fd_t fp = b->fp;
return FD2INT (fp);
}
return -1;
}
/****************
* Tell the file position, where the next read will take place
*/
off_t
iobuf_tell (iobuf_t a)
{
return a->ntotal + a->nbytes;
}
#if !defined(HAVE_FSEEKO) && !defined(fseeko)
#ifdef HAVE_LIMITS_H
# include <limits.h>
#endif
#ifndef LONG_MAX
# define LONG_MAX ((long) ((unsigned long) -1 >> 1))
#endif
#ifndef LONG_MIN
# define LONG_MIN (-1 - LONG_MAX)
#endif
/****************
* A substitute for fseeko, for hosts that don't have it.
*/
static int
fseeko (FILE * stream, off_t newpos, int whence)
{
while (newpos != (long) newpos)
{
long pos = newpos < 0 ? LONG_MIN : LONG_MAX;
if (fseek (stream, pos, whence) != 0)
return -1;
newpos -= pos;
whence = SEEK_CUR;
}
return fseek (stream, (long) newpos, whence);
}
#endif
/****************
* This is a very limited implementation. It simply discards all internal
* buffering and removes all filters but the first one.
*/
int
iobuf_seek (iobuf_t a, off_t newpos)
{
file_filter_ctx_t *b = NULL;
if (a->use != IOBUF_TEMP)
{
for (; a; a = a->chain)
{
if (!a->chain && a->filter == file_filter)
{
b = a->filter_ov;
break;
}
}
if (!a)
return -1;
#ifdef HAVE_W32_SYSTEM
if (SetFilePointer (b->fp, newpos, NULL, FILE_BEGIN) == 0xffffffff)
{
log_error ("SetFilePointer failed on handle %p: ec=%d\n",
b->fp, (int) GetLastError ());
return -1;
}
#else
if (lseek (b->fp, newpos, SEEK_SET) == (off_t) - 1)
{
log_error ("can't lseek: %s\n", strerror (errno));
return -1;
}
#endif
}
/* Discard the buffer unless it is a temp stream. */
if (a->use != IOBUF_TEMP)
a->d.len = 0;
a->d.start = 0;
a->nbytes = 0;
a->nlimit = 0;
a->nofast = 0;
a->ntotal = newpos;
a->error = 0;
/* remove filters, but the last */
if (a->chain)
log_debug ("pop_filter called in iobuf_seek - please report\n");
while (a->chain)
pop_filter (a, a->filter, NULL);
return 0;
}
/****************
* Retrieve the real filename. This is the filename actually used on
* disk and not a made up one. Returns NULL if no real filename is
* available.
*/
const char *
iobuf_get_real_fname (iobuf_t a)
{
if (a->real_fname)
return a->real_fname;
/* the old solution */
for (; a; a = a->chain)
if (!a->chain && a->filter == file_filter)
{
file_filter_ctx_t *b = a->filter_ov;
return b->print_only_name ? NULL : b->fname;
}
return NULL;
}
/****************
* Retrieve the filename. This name should only be used in diagnostics.
*/
const char *
iobuf_get_fname (iobuf_t a)
{
for (; a; a = a->chain)
if (!a->chain && a->filter == file_filter)
{
file_filter_ctx_t *b = a->filter_ov;
return b->fname;
}
return NULL;
}
/* Same as iobuf_get_fname but never returns NULL. */
const char *
iobuf_get_fname_nonnull (iobuf_t a)
{
const char *fname;
fname = iobuf_get_fname (a);
return fname? fname : "[?]";
}
/****************
* enable partial block mode as described in the OpenPGP draft.
* LEN is the first length byte on read, but ignored on writes.
*/
void
iobuf_set_partial_block_mode (iobuf_t a, size_t len)
{
block_filter_ctx_t *ctx = xcalloc (1, sizeof *ctx);
assert (a->use == IOBUF_INPUT || a->use == IOBUF_OUTPUT);
ctx->use = a->use;
if (!len)
{
if (a->use == IOBUF_INPUT)
log_debug ("pop_filter called in set_partial_block_mode"
" - please report\n");
pop_filter (a, block_filter, NULL);
}
else
{
ctx->partial = 1;
ctx->size = 0;
ctx->first_c = len;
iobuf_push_filter (a, block_filter, ctx);
}
}
/****************
* Same as fgets() but if the buffer is too short a larger one will
* be allocated up to some limit *max_length.
* A line is considered a byte stream ending in a LF.
* Returns the length of the line. EOF is indicated by a line of
* length zero. The last LF may be missing due to an EOF.
* is max_length is zero on return, the line has been truncated.
*
* Note: The buffer is allocated with enough space to append a CR,LF,EOL
*/
unsigned int
iobuf_read_line (iobuf_t a, byte ** addr_of_buffer,
unsigned *length_of_buffer, unsigned *max_length)
{
int c;
char *buffer = (char *)*addr_of_buffer;
unsigned length = *length_of_buffer;
unsigned nbytes = 0;
unsigned maxlen = *max_length;
char *p;
if (!buffer)
{ /* must allocate a new buffer */
length = 256;
buffer = xmalloc (length);
*addr_of_buffer = (unsigned char *)buffer;
*length_of_buffer = length;
}
length -= 3; /* reserve 3 bytes (cr,lf,eol) */
p = buffer;
while ((c = iobuf_get (a)) != -1)
{
if (nbytes == length)
{ /* increase the buffer */
if (length > maxlen)
{ /* this is out limit */
/* skip the rest of the line */
while (c != '\n' && (c = iobuf_get (a)) != -1)
;
*p++ = '\n'; /* always append a LF (we have reserved space) */
nbytes++;
*max_length = 0; /* indicate truncation */
break;
}
length += 3; /* correct for the reserved byte */
length += length < 1024 ? 256 : 1024;
buffer = xrealloc (buffer, length);
*addr_of_buffer = (unsigned char *)buffer;
*length_of_buffer = length;
length -= 3; /* and reserve again */
p = buffer + nbytes;
}
*p++ = c;
nbytes++;
if (c == '\n')
break;
}
*p = 0; /* make sure the line is a string */
return nbytes;
}
static int
translate_file_handle (int fd, int for_write)
{
#if defined(HAVE_W32CE_SYSTEM)
/* This is called only with one of the special filenames. Under
W32CE the FD here is not a file descriptor but a rendezvous id,
thus we need to finish the pipe first. */
fd = _assuan_w32ce_finish_pipe (fd, for_write);
#elif defined(HAVE_W32_SYSTEM)
{
int x;
(void)for_write;
if (fd == 0)
x = (int) GetStdHandle (STD_INPUT_HANDLE);
else if (fd == 1)
x = (int) GetStdHandle (STD_OUTPUT_HANDLE);
else if (fd == 2)
x = (int) GetStdHandle (STD_ERROR_HANDLE);
else
x = fd;
if (x == -1)
log_debug ("GetStdHandle(%d) failed: ec=%d\n",
fd, (int) GetLastError ());
fd = x;
}
#else
(void)for_write;
#endif
return fd;
}
void
iobuf_skip_rest (iobuf_t a, unsigned long n, int partial)
{
if ( partial )
{
for (;;)
{
if (a->nofast || a->d.start >= a->d.len)
{
if (iobuf_readbyte (a) == -1)
{
break;
}
}
else
{
unsigned long count = a->d.len - a->d.start;
a->nbytes += count;
a->d.start = a->d.len;
}
}
}
else
{
unsigned long remaining = n;
while (remaining > 0)
{
if (a->nofast || a->d.start >= a->d.len)
{
if (iobuf_readbyte (a) == -1)
{
break;
}
--remaining;
}
else
{
unsigned long count = a->d.len - a->d.start;
if (count > remaining)
{
count = remaining;
}
a->nbytes += count;
a->d.start += count;
remaining -= count;
}
}
}
}

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Expires
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Storage Format
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Storage Handle
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