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Diffstat (limited to 'common/iobuf.c')
| -rw-r--r-- | common/iobuf.c | 2698 |
1 files changed, 2698 insertions, 0 deletions
diff --git a/common/iobuf.c b/common/iobuf.c new file mode 100644 index 0000000..6370efb --- /dev/null +++ b/common/iobuf.c @@ -0,0 +1,2698 @@ +/* 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 <https://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; + +int iobuf_debug_mode; + + +#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 more efficient) 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; + + +/* Local prototypes. */ +static int underflow (iobuf_t a, int clear_pending_eof); +static int underflow_target (iobuf_t a, int clear_pending_eof, size_t target); +static int translate_file_handle (int fd, int for_write); + +/* Sends any pending data to the filter's FILTER function. Note: this + works on the filter and not on the whole pipeline. That is, + iobuf_flush doesn't necessarily cause data to be written to any + underlying file; it just causes any data buffered at the filter A + to be sent to A's filter function. + + If A is a IOBUF_OUTPUT_TEMP filter, then this also enlarges the + buffer by IOBUF_BUFFER_SIZE. + + May only be called on an IOBUF_OUTPUT or IOBUF_OUTPUT_TEMP filters. */ +static int filter_flush (iobuf_t a); + + + +/* 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; + + (void)mode700; + /* 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; + } + + /* We always use the Unicode version because it supports file names + * longer than MAX_PATH. (requires gpgrt 1.45) */ + if (1) + { + wchar_t *wfname = gpgrt_fname_to_wchar (fname); + if (wfname) + { + hfile = CreateFileW (wfname, da, sm, NULL, cd, + FILE_ATTRIBUTE_NORMAL, NULL); + xfree (wfname); + } + else + hfile = INVALID_HANDLE_VALUE; + } + + 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 a 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); +} + + +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) + { + mem2str (buf, "file_filter(fd)", *ret_len); + } + 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); + } + 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) + { + mem2str (buf, "estream_filter", *ret_len); + } + 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) + { + mem2str (buf, "sock_filter", *ret_len); + } + 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 = iobuf_get_noeof (chain) << 24; + a->size |= iobuf_get_noeof (chain) << 16; + a->size |= iobuf_get_noeof (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) + { + mem2str (buf, "block_filter", *ret_len); + } + 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; +} + +#define MAX_IOBUF_DESC 32 +/* + * Fill the buffer by the description of iobuf A. + * The buffer size should be MAX_IOBUF_DESC (or larger). + * Returns BUF as (const char *). + */ +static const char * +iobuf_desc (iobuf_t a, byte *buf) +{ + size_t len = MAX_IOBUF_DESC; + + if (! a || ! a->filter) + memcpy (buf, "?", 2); + else + a->filter (a->filter_ov, IOBUFCTRL_DESC, NULL, buf, &len); + + return buf; +} + +static void +print_chain (iobuf_t a) +{ + if (!DBG_IOBUF) + return; + for (; a; a = a->chain) + { + byte desc[MAX_IOBUF_DESC]; + + log_debug ("iobuf chain: %d.%d '%s' filter_eof=%d start=%d len=%d\n", + a->no, a->subno, iobuf_desc (a, desc), a->filter_eof, + (int) a->d.start, (int) a->d.len); + } +} + +int +iobuf_print_chain (iobuf_t a) +{ + print_chain (a); + return 0; +} + +iobuf_t +iobuf_alloc (int use, size_t bufsize) +{ + iobuf_t a; + static int number = 0; + + assert (use == IOBUF_INPUT || use == IOBUF_INPUT_TEMP + || use == IOBUF_OUTPUT || use == IOBUF_OUTPUT_TEMP); + if (bufsize == 0) + { + log_bug ("iobuf_alloc() passed a bufsize of 0!\n"); + bufsize = IOBUF_BUFFER_SIZE; + } + + 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 a_chain; + size_t dummy_len = 0; + int rc = 0; + + for (; a; a = a_chain) + { + byte desc[MAX_IOBUF_DESC]; + int rc2 = 0; + + a_chain = a->chain; + + if (a->use == IOBUF_OUTPUT && (rc = filter_flush (a))) + log_error ("filter_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, desc)); + + if (a->filter && (rc2 = a->filter (a->filter_ov, IOBUFCTRL_FREE, + a->chain, NULL, &dummy_len))) + log_error ("IOBUFCTRL_FREE failed on close: %s\n", gpg_strerror (rc)); + if (! rc && rc2) + /* Whoops! An error occurred. Save it in RC if we haven't + already recorded an error. */ + rc = rc2; + + 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 removing open files. So + * we have to do it here */ + gnupg_remove (remove_name); + xfree (remove_name); + } +#endif + return rc; +} + + +iobuf_t +iobuf_temp (void) +{ + return iobuf_alloc (IOBUF_OUTPUT_TEMP, IOBUF_BUFFER_SIZE); +} + +iobuf_t +iobuf_temp_with_content (const char *buffer, size_t length) +{ + iobuf_t a; + int i; + + a = iobuf_alloc (IOBUF_INPUT_TEMP, length); + assert (length == a->d.size); + /* memcpy (a->d.buf, buffer, length); */ + for (i=0; i < length; i++) + a->d.buf[i] = buffer[i]; + a->d.len = length; + + return a; +} + + +int +iobuf_is_pipe_filename (const char *fname) +{ + if (!fname || (*fname=='-' && !fname[1]) ) + return 1; + return check_special_filename (fname, 0, 1) != -1; +} + + +static iobuf_t +do_open (const char *fname, int special_filenames, + int use, const char *opentype, int mode700) +{ + iobuf_t a; + gnupg_fd_t fp; + file_filter_ctx_t *fcx; + size_t len = 0; + int print_only = 0; + int fd; + byte desc[MAX_IOBUF_DESC]; + + assert (use == IOBUF_INPUT || use == IOBUF_OUTPUT); + + if (special_filenames + /* NULL or '-'. */ + && (!fname || (*fname == '-' && !fname[1]))) + { + if (use == IOBUF_INPUT) + { + fp = FD_FOR_STDIN; + fname = "[stdin]"; + } + else + { + fp = FD_FOR_STDOUT; + fname = "[stdout]"; + } + print_only = 1; + } + else if (!fname) + return NULL; + else if (special_filenames + && (fd = check_special_filename (fname, 0, 1)) != -1) + return iobuf_fdopen (translate_file_handle (fd, use == IOBUF_INPUT ? 0 : 1), + opentype); + else + { + if (use == IOBUF_INPUT) + fp = fd_cache_open (fname, opentype); + else + fp = direct_open (fname, opentype, mode700); + if (fp == GNUPG_INVALID_FD) + return NULL; + } + + a = iobuf_alloc (use, 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' desc=%s fd=%d\n", + a->no, a->subno, fname, iobuf_desc (a, desc), FD2INT (fcx->fp)); + + return a; +} + +iobuf_t +iobuf_open (const char *fname) +{ + return do_open (fname, 1, IOBUF_INPUT, "rb", 0); +} + +iobuf_t +iobuf_create (const char *fname, int mode700) +{ + return do_open (fname, 1, IOBUF_OUTPUT, "wb", mode700); +} + +iobuf_t +iobuf_openrw (const char *fname) +{ + return do_open (fname, 0, IOBUF_OUTPUT, "r+b", 0); +} + + +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; +} + + +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 = 0; + + 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; +} + +int +iobuf_ioctl (iobuf_t a, iobuf_ioctl_t cmd, int intval, void *ptrval) +{ + byte desc[MAX_IOBUF_DESC]; + + 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, desc), + 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, desc), + 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 = filter_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; + } + + /* We want to create a new filter and put it in front of A. A + simple implementation would do: + + b = iobuf_alloc (...); + b->chain = a; + return a; + + This is a bit problematic: A is the head of the pipeline and + there are potentially many pointers to it. Requiring the caller + to update all of these pointers is a burden. + + An alternative implementation would add a level of indirection. + For instance, we could use a pipeline object, which contains a + pointer to the first filter in the pipeline. This is not what we + do either. + + Instead, we allocate a new buffer (B) and copy the first filter's + state into that and use the initial buffer (A) for the new + filter. One limitation of this approach is that it is not + practical to maintain a pointer to a specific filter's state. + + Before: + + A + | + v 0x100 0x200 + +----------+ +----------+ + | filter x |--------->| filter y |---->.... + +----------+ +----------+ + + After: B + | + v 0x300 + +----------+ + A | filter x | + | +----------+ + v 0x100 ^ v 0x200 + +----------+ +----------+ + | filter w | | filter y |---->.... + +----------+ +----------+ + + Note: filter x's address changed from 0x100 to 0x300, but A still + points to the head of the pipeline. + */ + + 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_OUTPUT_TEMP) + /* A TEMP filter buffers any data sent to it; it does not forward + any data down the pipeline. If we add a new filter to the + pipeline, it shouldn't also buffer data. It should send it + downstream to be buffered. Thus, the correct type for a filter + added in front of an IOBUF_OUTPUT_TEMP filter is IOBUF_OUPUT, not + IOBUF_OUTPUT_TEMP. */ + { + a->use = IOBUF_OUTPUT; + + /* When pipeline is written to, the temp buffer's size is + increased accordingly. We don't need to allocate a 10 MB + buffer for a non-terminal filter. Just use the default + size. */ + a->d.size = IOBUF_BUFFER_SIZE; + } + else if (a->use == IOBUF_INPUT_TEMP) + /* Same idea as above. */ + { + a->use = IOBUF_INPUT; + a->d.size = IOBUF_BUFFER_SIZE; + } + + /* The new filter (A) gets a new buffer. + + If the pipeline is an output or temp pipeline, then giving the + buffer to the new filter means that data that was written before + the filter was pushed gets sent to the filter. That's clearly + wrong. + + If the pipeline is an input pipeline, then giving the buffer to + the new filter (A) means that data that has read from (B), but + not yet read from the pipeline won't be processed by the new + filter (A)! That's certainly not what we want. */ + 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) + { + byte desc[MAX_IOBUF_DESC]; + log_debug ("iobuf-%d.%d: push '%s'\n", + a->no, a->subno, iobuf_desc (a, desc)); + 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. + */ +int +iobuf_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; + byte desc[MAX_IOBUF_DESC]; + + if (DBG_IOBUF) + log_debug ("iobuf-%d.%d: pop '%s'\n", + a->no, a->subno, iobuf_desc (a, desc)); + if (a->use == IOBUF_INPUT_TEMP || a->use == IOBUF_OUTPUT_TEMP) + { + /* This should be the last filter in the pipeline. */ + assert (! a->chain); + return 0; + } + 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 ("iobuf_pop_filter(): filter function not found\n"); + + /* flush this stream if it is an output stream */ + if (a->use == IOBUF_OUTPUT && (rc = filter_flush (b))) + { + log_error ("filter_flush failed in iobuf_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 at least one byte into the buffer and return + * the first byte or -1 on EOF. + */ +static int +underflow (iobuf_t a, int clear_pending_eof) +{ + return underflow_target (a, clear_pending_eof, 1); +} + + +/**************** + * read underflow: read TARGET bytes into the buffer and return + * the first byte or -1 on EOF. + */ +static int +underflow_target (iobuf_t a, int clear_pending_eof, size_t target) +{ + size_t len; + int rc; + + if (DBG_IOBUF) + log_debug ("iobuf-%d.%d: underflow: buffer size: %d; still buffered: %d => space for %d bytes\n", + a->no, a->subno, + (int) a->d.size, (int) (a->d.len - a->d.start), + (int) (a->d.size - (a->d.len - a->d.start))); + + if (a->use == IOBUF_INPUT_TEMP) + /* By definition, there isn't more data to read into the + buffer. */ + return -1; + + assert (a->use == IOBUF_INPUT); + + /* If there is still some buffered data, then move it to the start + of the buffer and try to fill the end of the buffer. (This is + useful if we are called from iobuf_peek().) */ + assert (a->d.start <= a->d.len); + a->d.len -= a->d.start; + memmove (a->d.buf, &a->d.buf[a->d.start], a->d.len); + a->d.start = 0; + + if (a->d.len < target && a->filter_eof) + /* The last time we tried to read from this filter, we got an EOF. + We couldn't return the EOF, because there was buffered data. + Since there is no longer any buffered data, return the + error. */ + { + if (DBG_IOBUF) + log_debug ("iobuf-%d.%d: underflow: eof (pending eof)\n", + a->no, a->subno); + if (! clear_pending_eof) + return -1; + + if (a->chain) + /* A filter follows this one. Free this filter. */ + { + iobuf_t b = a->chain; + if (DBG_IOBUF) + log_debug ("iobuf-%d.%d: filter popped (pending EOF returned)\n", + a->no, a->subno); + 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 */ + return -1; /* return one(!) EOF */ + } + + if (a->d.len == 0 && a->error) + /* The last time we tried to read from this filter, we got an + error. We couldn't return the error, because there was + buffered data. Since there is no longer any buffered data, + return the error. */ + { + if (DBG_IOBUF) + log_debug ("iobuf-%d.%d: pending error (%s) returned\n", + a->no, a->subno, gpg_strerror (a->error)); + return -1; + } + + if (a->filter && ! a->filter_eof && ! a->error) + /* We have a filter function and the last time we tried to read we + didn't get an EOF or an error. Try to fill the buffer. */ + { + /* Be careful to account for any buffered data. */ + len = a->d.size - a->d.len; + if (DBG_IOBUF) + log_debug ("iobuf-%d.%d: underflow: A->FILTER (%lu bytes)\n", + a->no, a->subno, (ulong) len); + if (len == 0) + /* There is no space for more data. Don't bother calling + A->FILTER. */ + rc = 0; + else + rc = a->filter (a->filter_ov, IOBUFCTRL_UNDERFLOW, a->chain, + &a->d.buf[a->d.len], &len); + a->d.len += len; + + if (DBG_IOBUF) + log_debug ("iobuf-%d.%d: A->FILTER() returned rc=%d (%s), read %lu bytes\n", + a->no, a->subno, + rc, rc == 0 ? "ok" : rc == -1 ? "EOF" : gpg_strerror (rc), + (ulong) len); +/* if( a->no == 1 ) */ +/* log_hexdump (" data:", a->d.buf, len); */ + + if (rc == -1) + /* EOF. */ + { + size_t dummy_len = 0; + + /* 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)); + + /* Free everything except for the internal buffer. */ + if (a->filter_ov && a->filter_ov_owner) + xfree (a->filter_ov); + a->filter_ov = NULL; + a->filter = NULL; + a->filter_eof = 1; + + if (clear_pending_eof && a->d.len == 0 && a->chain) + /* We don't need to keep this filter around at all: + + - we got an EOF + - we have no buffered data + - a filter follows this one. + + Unlink this filter. */ + { + iobuf_t b = a->chain; + if (DBG_IOBUF) + log_debug ("iobuf-%d.%d: pop in underflow (nothing buffered, got EOF)\n", + a->no, a->subno); + xfree (a->d.buf); + xfree (a->real_fname); + memcpy (a, b, sizeof *a); + xfree (b); + + print_chain (a); + + return -1; + } + else if (a->d.len == 0) + /* We can't unlink this filter (it is the only one in the + pipeline), but we can immediately return EOF. */ + return -1; + } + else if (rc) + /* Record the error. */ + { + a->error = rc; + + if (a->d.len == 0) + /* There is no buffered data. Immediately return EOF. */ + return -1; + } + } + + assert (a->d.start <= a->d.len); + if (a->d.start < a->d.len) + return a->d.buf[a->d.start++]; + + /* EOF. */ + return -1; +} + + +static int +filter_flush (iobuf_t a) +{ + size_t len; + int rc; + + if (a->use == IOBUF_OUTPUT_TEMP) + { /* increase the temp buffer */ + 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); + + a->d.buf = xrealloc (a->d.buf, newsize); + 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 ("filter_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 ("filter_flush did not write all!\n"); + rc = GPG_ERR_INTERNAL; + } + else if (rc) + a->error = rc; + a->d.len = 0; + + return rc; +} + + +int +iobuf_readbyte (iobuf_t a) +{ + int c; + + if (a->use == IOBUF_OUTPUT || a->use == IOBUF_OUTPUT_TEMP) + { + log_bug ("iobuf_readbyte called on a non-INPUT pipeline!\n"); + return -1; + } + + assert (a->d.start <= a->d.len); + + 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)) == -1) + return -1; /* EOF */ + + assert (a->d.start <= a->d.len); + + /* Note: if underflow doesn't return EOF, then it returns the first + byte that was read and advances a->d.start appropriately. */ + + 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->use == IOBUF_OUTPUT || a->use == IOBUF_OUTPUT_TEMP) + { + log_bug ("iobuf_read called on a non-INPUT pipeline!\n"); + return -1; + } + + if (a->nlimit) + { + /* Handle special cases. */ + for (n = 0; n < buflen; n++) + { + if ((c = iobuf_readbyte (a)) == -1) + { + if (!n) + return -1; /* eof */ + break; + } + + if (buf) + { + *buf = c; + buf++; + } + } + return n; + } + + n = 0; + do + { + if (n < buflen && a->d.start < a->d.len) + /* Drain the buffer. */ + { + 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) + /* Draining the internal buffer didn't fill BUFFER. Call + underflow to read more data into the filter's internal + buffer. */ + { + if ((c = underflow (a, 1)) == -1) + /* EOF. If we managed to read something, don't return EOF + now. */ + { + a->nbytes += n; + return n ? n : -1 /*EOF*/; + } + if (buf) + *buf++ = c; + n++; + } + } + while (n < buflen); + a->nbytes += n; + return n; +} + + + +int +iobuf_peek (iobuf_t a, byte * buf, unsigned buflen) +{ + int n = 0; + + assert (buflen > 0); + assert (a->use == IOBUF_INPUT || a->use == IOBUF_INPUT_TEMP); + + if (buflen > a->d.size) + /* We can't peek more than we can buffer. */ + buflen = a->d.size; + + /* Try to fill the internal buffer with enough data to satisfy the + request. */ + while (buflen > a->d.len - a->d.start) + { + if (underflow_target (a, 0, buflen) == -1) + /* EOF. We can't read any more. */ + break; + + /* Underflow consumes the first character (it's the return + value). unget() it by resetting the "file position". */ + assert (a->d.start == 1); + a->d.start = 0; + } + + n = a->d.len - a->d.start; + if (n > buflen) + n = buflen; + + if (n == 0) + /* EOF. */ + return -1; + + memcpy (buf, &a->d.buf[a->d.start], n); + + return n; +} + + + + +int +iobuf_writebyte (iobuf_t a, unsigned int c) +{ + int rc; + + if (a->use == IOBUF_INPUT || a->use == IOBUF_INPUT_TEMP) + { + log_bug ("iobuf_writebyte called on an input pipeline!\n"); + return -1; + } + + if (a->d.len == a->d.size) + if ((rc=filter_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; + + if (a->use == IOBUF_INPUT || a->use == IOBUF_INPUT_TEMP) + { + log_bug ("iobuf_write called on an input pipeline!\n"); + return -1; + } + + 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 = filter_flush (a); + if (rc) + return rc; + } + } + while (buflen); + return 0; +} + + +int +iobuf_writestr (iobuf_t a, const char *buf) +{ + if (a->use == IOBUF_INPUT || a->use == IOBUF_INPUT_TEMP) + { + log_bug ("iobuf_writestr called on an input pipeline!\n"); + return -1; + } + + return iobuf_write (a, buf, strlen (buf)); +} + + + +int +iobuf_write_temp (iobuf_t dest, iobuf_t source) +{ + assert (source->use == IOBUF_OUTPUT || source->use == IOBUF_OUTPUT_TEMP); + assert (dest->use == IOBUF_OUTPUT || dest->use == IOBUF_OUTPUT_TEMP); + + iobuf_flush_temp (source); + return iobuf_write (dest, source->d.buf, source->d.len); +} + +size_t +iobuf_temp_to_buffer (iobuf_t a, byte * buffer, size_t buflen) +{ + byte desc[MAX_IOBUF_DESC]; + size_t n; + + while (1) + { + int rc = filter_flush (a); + if (rc) + log_bug ("Flushing iobuf %d.%d (%s) from iobuf_temp_to_buffer failed. Ignoring.\n", + a->no, a->subno, iobuf_desc (a, desc)); + if (! a->chain) + break; + a = a->chain; + } + + n = a->d.len; + if (n > buflen) + n = buflen; + memcpy (buffer, a->d.buf, n); + return n; +} + +/* Copies the data from the input iobuf SOURCE to the output iobuf + DEST until either an error is encountered or EOF is reached. + Returns the number of bytes copies or (size_t)(-1) on error. */ +size_t +iobuf_copy (iobuf_t dest, iobuf_t source) +{ + char *temp; + /* Use a 32 KB buffer. */ + const size_t temp_size = 32 * 1024; + + size_t nread; + size_t nwrote = 0; + size_t max_read = 0; + int err; + + log_assert (source->use == IOBUF_INPUT || source->use == IOBUF_INPUT_TEMP); + log_assert (dest->use == IOBUF_OUTPUT || source->use == IOBUF_OUTPUT_TEMP); + + if (iobuf_error (dest)) + return (size_t)(-1); + + temp = xmalloc (temp_size); + while (1) + { + nread = iobuf_read (source, temp, temp_size); + if (nread == -1) + /* EOF. */ + break; + + if (nread > max_read) + max_read = nread; + + err = iobuf_write (dest, temp, nread); + if (err) + break; + nwrote += nread; + } + + /* Burn the buffer. */ + if (max_read) + wipememory (temp, max_read); + xfree (temp); + + return nwrote; +} + + +void +iobuf_flush_temp (iobuf_t temp) +{ + if (temp->use == IOBUF_INPUT || temp->use == IOBUF_INPUT_TEMP) + log_bug ("iobuf_flush_temp called on an input pipeline!\n"); + while (temp->chain) + iobuf_pop_filter (temp, temp->filter, NULL); +} + + +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; +} + + + +off_t +iobuf_get_filelength (iobuf_t a, int *overflow) +{ + if (overflow) + *overflow = 0; + + /* Hmmm: file_filter may have already been removed */ + for ( ; a->chain; a = a->chain ) + ; + + if (a->filter != file_filter) + return 0; + + { + 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 (-1)); +#else /*!HAVE_W32_SYSTEM*/ + { + struct stat st; + + if ( !fstat (FD2INT (fp), &st) ) + return st.st_size; + log_error("fstat() failed: %s\n", strerror(errno) ); + } +#endif /*!HAVE_W32_SYSTEM*/ + } + + return 0; +} + + +int +iobuf_get_fd (iobuf_t a) +{ + for (; a->chain; a = a->chain) + ; + + if (a->filter != file_filter) + return -1; + + { + file_filter_ctx_t *b = a->filter_ov; + gnupg_fd_t fp = b->fp; + + return FD2INT (fp); + } +} + + +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 + +int +iobuf_seek (iobuf_t a, off_t newpos) +{ + file_filter_ctx_t *b = NULL; + + if (a->use == IOBUF_OUTPUT || a->use == IOBUF_INPUT) + { + /* Find the last filter in the pipeline. */ + for (; a->chain; a = a->chain) + ; + + if (a->filter != file_filter) + return -1; + + b = a->filter_ov; + +#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 it is not a temp stream. */ + a->d.len = 0; + } + a->d.start = 0; + a->nbytes = 0; + a->nlimit = 0; + a->nofast = 0; + a->ntotal = newpos; + a->error = 0; + + /* It is impossible for A->CHAIN to be non-NULL. If A is an INPUT + or OUTPUT buffer, then we find the last filter, which is defined + as A->CHAIN being NULL. If A is a TEMP filter, then A must be + the only filter in the pipe: when iobuf_push_filter adds a filter + to the front of a pipeline, it sets the new filter to be an + OUTPUT filter if the pipeline is an OUTPUT or TEMP pipeline and + to be an INPUT filter if the pipeline is an INPUT pipeline. + Thus, only the last filter in a TEMP pipeline can be a */ + + /* remove filters, but the last */ + if (a->chain) + log_debug ("iobuf_pop_filter called in iobuf_seek - please report\n"); + while (a->chain) + iobuf_pop_filter (a, a->filter, NULL); + + return 0; +} + + +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; +} + +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; +} + +const char * +iobuf_get_fname_nonnull (iobuf_t a) +{ + const char *fname; + + fname = iobuf_get_fname (a); + return fname? fname : "[?]"; +} + + +/**************** + * Enable or disable partial body length mode (RFC 4880 4.2.2.4). + * + * If LEN is 0, this disables partial block mode by popping the + * partial body length filter, which must be the most recently + * added filter. + * + * If LEN is non-zero, it pushes a partial body length filter. If + * this is a read filter, LEN must be the length byte from the first + * chunk and A should be position just after this first partial body + * length header. + */ +void +iobuf_set_partial_body_length_mode (iobuf_t a, size_t len) +{ + if (!len) + /* Disable partial body length mode. */ + { + if (a->use == IOBUF_INPUT) + log_debug ("iobuf_pop_filter called in set_partial_block_mode" + " - please report\n"); + + log_assert (a->filter == block_filter); + iobuf_pop_filter (a, block_filter, NULL); + } + else + /* Enabled partial body length mode. */ + { + block_filter_ctx_t *ctx = xcalloc (1, sizeof *ctx); + ctx->use = a->use; + ctx->partial = 1; + ctx->size = 0; + ctx->first_c = len; + iobuf_push_filter (a, block_filter, ctx); + } +} + + + +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; + + /* The code assumes that we have space for at least a newline and a + NUL character in the buffer. This requires at least 2 bytes. We + don't complicate the code by handling the stupid corner case, but + simply assert that it can't happen. */ + assert (!buffer || length >= 2 || maxlen >= 2); + + if (!buffer || length <= 1) + /* must allocate a new buffer */ + { + length = 256 <= maxlen ? 256 : maxlen; + buffer = xrealloc (buffer, length); + *addr_of_buffer = (unsigned char *)buffer; + *length_of_buffer = length; + } + + p = buffer; + while ((c = iobuf_get (a)) != -1) + { + *p++ = c; + nbytes++; + if (c == '\n') + break; + + if (nbytes == length - 1) + /* We don't have enough space to add a \n and a \0. Increase + the buffer size. */ + { + if (length == maxlen) + /* We reached the buffer's size limit! */ + { + /* Skip the rest of the line. */ + while (c != '\n' && (c = iobuf_get (a)) != -1) + ; + + /* p is pointing at the last byte in the buffer. We + always terminate the line with "\n\0" so overwrite + the previous byte with a \n. */ + assert (p > buffer); + p[-1] = '\n'; + + /* Indicate truncation. */ + *max_length = 0; + break; + } + + length += length < 1024 ? 256 : 1024; + if (length > maxlen) + length = maxlen; + + buffer = xrealloc (buffer, length); + *addr_of_buffer = (unsigned char *)buffer; + *length_of_buffer = length; + p = buffer + nbytes; + } + } + /* Add the terminating NUL. */ + *p = 0; + + /* Return the number of characters written to the buffer including + the newline, but not including the terminating NUL. */ + 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; + } + } + } +} |