gpg: Report BEGIN_* status before examining the input.

* common/miscellaneous.c (is_openpgp_compressed_packet)
(is_file_compressed): Moved to ...
* common/iobuf.c: ... in this file.
(is_file_compressed): Change the argument to INP, the iobuf.
* common/util.h (is_file_compressed): Remove.
* common/iobuf.h (is_file_compressed): Add.
* g10/cipher-aead.c (write_header): Don't call write_status_printf
here.
(cipher_filter_aead): Call write_status_printf when called with
IOBUFCTRL_INIT.
* g10/cipher-cfb.c (write_header): Don't call write_status_printf
here.
(cipher_filter_cfb): Call write_status_printf when called with
IOBUFCTRL_INIT.
* g10/encrypt.c (encrypt_simple): Use new is_file_compressed function,
after call of iobuf_push_filter.
(encrypt_crypt): Likewise.
* g10/sign.c (sign_file): Likewise.

--

GnuPG-bug-id: 6481
Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>
This commit is contained in:
NIIBE Yutaka 2023-05-24 10:36:04 +09:00
parent b789ada2b0
commit 2f872fa68c
No known key found for this signature in database
GPG Key ID: 640114AF89DE6054
8 changed files with 174 additions and 189 deletions

View File

@ -3057,3 +3057,123 @@ iobuf_skip_rest (iobuf_t a, unsigned long n, int partial)
}
}
}
/* Check whether (BUF,LEN) is valid header for an OpenPGP compressed
* packet. LEN should be at least 6. */
static int
is_openpgp_compressed_packet (const unsigned char *buf, size_t len)
{
int c, ctb, pkttype;
int lenbytes;
ctb = *buf++; len--;
if (!(ctb & 0x80))
return 0; /* Invalid packet. */
if ((ctb & 0x40)) /* New style (OpenPGP) CTB. */
{
pkttype = (ctb & 0x3f);
if (!len)
return 0; /* Expected first length octet missing. */
c = *buf++; len--;
if (c < 192)
;
else if (c < 224)
{
if (!len)
return 0; /* Expected second length octet missing. */
}
else if (c == 255)
{
if (len < 4)
return 0; /* Expected length octets missing */
}
}
else /* Old style CTB. */
{
pkttype = (ctb>>2)&0xf;
lenbytes = ((ctb&3)==3)? 0 : (1<<(ctb & 3));
if (len < lenbytes)
return 0; /* Not enough length bytes. */
}
return (pkttype == 8);
}
/*
* Check if the file is compressed, by peeking the iobuf. You need to
* pass the iobuf with INP. Returns true if the buffer seems to be
* compressed.
*/
int
is_file_compressed (iobuf_t inp)
{
int i;
char buf[32];
int buflen;
struct magic_compress_s
{
byte len;
byte extchk;
byte magic[5];
} magic[] =
{
{ 3, 0, { 0x42, 0x5a, 0x68, 0x00 } }, /* bzip2 */
{ 3, 0, { 0x1f, 0x8b, 0x08, 0x00 } }, /* gzip */
{ 4, 0, { 0x50, 0x4b, 0x03, 0x04 } }, /* (pk)zip */
{ 5, 0, { '%', 'P', 'D', 'F', '-'} }, /* PDF */
{ 4, 1, { 0xff, 0xd8, 0xff, 0xe0 } }, /* Maybe JFIF */
{ 5, 2, { 0x89, 'P','N','G', 0x0d} } /* Likely PNG */
};
if (!inp)
return 0;
for ( ; inp->chain; inp = inp->chain )
;
buflen = iobuf_ioctl (inp, IOBUF_IOCTL_PEEK, sizeof buf, buf);
if (buflen < 0)
{
buflen = 0;
log_debug ("peeking at input failed\n");
}
if ( buflen < 6 )
{
return 0; /* Too short to check - assume uncompressed. */
}
for ( i = 0; i < DIM (magic); i++ )
{
if (!memcmp( buf, magic[i].magic, magic[i].len))
{
switch (magic[i].extchk)
{
case 0:
return 1; /* Is compressed. */
case 1:
if (buflen > 11 && !memcmp (buf + 6, "JFIF", 5))
return 1; /* JFIF: this likely a compressed JPEG. */
break;
case 2:
if (buflen > 8
&& buf[5] == 0x0a && buf[6] == 0x1a && buf[7] == 0x0a)
return 1; /* This is a PNG. */
break;
default:
break;
}
}
}
if (buflen >= 6 && is_openpgp_compressed_packet (buf, buflen))
{
return 1; /* Already compressed. */
}
return 0; /* Not detected as compressed. */
}

View File

@ -629,6 +629,9 @@ void iobuf_set_partial_body_length_mode (iobuf_t a, size_t len);
from the following filter (which may or may not return EOF). */
void iobuf_skip_rest (iobuf_t a, unsigned long n, int partial);
/* Check if the file is compressed, by peeking the iobuf. */
int is_file_compressed (iobuf_t inp);
#define iobuf_where(a) "[don't know]"
/* Each time a filter is allocated (via iobuf_alloc()), a

View File

@ -415,112 +415,6 @@ decode_c_string (const char *src)
}
/* Check whether (BUF,LEN) is valid header for an OpenPGP compressed
* packet. LEN should be at least 6. */
static int
is_openpgp_compressed_packet (const unsigned char *buf, size_t len)
{
int c, ctb, pkttype;
int lenbytes;
ctb = *buf++; len--;
if (!(ctb & 0x80))
return 0; /* Invalid packet. */
if ((ctb & 0x40)) /* New style (OpenPGP) CTB. */
{
pkttype = (ctb & 0x3f);
if (!len)
return 0; /* Expected first length octet missing. */
c = *buf++; len--;
if (c < 192)
;
else if (c < 224)
{
if (!len)
return 0; /* Expected second length octet missing. */
}
else if (c == 255)
{
if (len < 4)
return 0; /* Expected length octets missing */
}
}
else /* Old style CTB. */
{
pkttype = (ctb>>2)&0xf;
lenbytes = ((ctb&3)==3)? 0 : (1<<(ctb & 3));
if (len < lenbytes)
return 0; /* Not enough length bytes. */
}
return (pkttype == 8);
}
/*
* Check if the file is compressed. You need to pass the first bytes
* of the file as (BUF,BUFLEN). Returns true if the buffer seems to
* be compressed.
*/
int
is_file_compressed (const byte *buf, unsigned int buflen)
{
int i;
struct magic_compress_s
{
byte len;
byte extchk;
byte magic[5];
} magic[] =
{
{ 3, 0, { 0x42, 0x5a, 0x68, 0x00 } }, /* bzip2 */
{ 3, 0, { 0x1f, 0x8b, 0x08, 0x00 } }, /* gzip */
{ 4, 0, { 0x50, 0x4b, 0x03, 0x04 } }, /* (pk)zip */
{ 5, 0, { '%', 'P', 'D', 'F', '-'} }, /* PDF */
{ 4, 1, { 0xff, 0xd8, 0xff, 0xe0 } }, /* Maybe JFIF */
{ 5, 2, { 0x89, 'P','N','G', 0x0d} } /* Likely PNG */
};
if ( buflen < 6 )
{
return 0; /* Too short to check - assume uncompressed. */
}
for ( i = 0; i < DIM (magic); i++ )
{
if (!memcmp( buf, magic[i].magic, magic[i].len))
{
switch (magic[i].extchk)
{
case 0:
return 1; /* Is compressed. */
case 1:
if (buflen > 11 && !memcmp (buf + 6, "JFIF", 5))
return 1; /* JFIF: this likely a compressed JPEG. */
break;
case 2:
if (buflen > 8
&& buf[5] == 0x0a && buf[6] == 0x1a && buf[7] == 0x0a)
return 1; /* This is a PNG. */
break;
default:
break;
}
}
}
if (buflen >= 6 && is_openpgp_compressed_packet (buf, buflen))
{
return 1; /* Already compressed. */
}
return 0; /* Not detected as compressed. */
}
/* Try match against each substring of multistr, delimited by | */
int
match_multistr (const char *multistr,const char *match)

View File

@ -360,8 +360,6 @@ char *try_make_printable_string (const void *p, size_t n, int delim);
char *make_printable_string (const void *p, size_t n, int delim);
char *decode_c_string (const char *src);
int is_file_compressed (const byte *buf, unsigned int buflen);
int match_multistr (const char *multistr,const char *match);
int gnupg_compare_version (const char *a, const char *b);

View File

@ -174,8 +174,6 @@ write_header (cipher_filter_context_t *cfx, iobuf_t a)
log_debug ("aead packet: len=%lu extralen=%d\n",
(unsigned long)ed.len, ed.extralen);
write_status_printf (STATUS_BEGIN_ENCRYPTION, "0 %d %d",
cfx->dek->algo, ed.aead_algo);
print_cipher_algo_note (cfx->dek->algo);
if (build_packet( a, &pkt))
@ -488,6 +486,11 @@ cipher_filter_aead (void *opaque, int control,
{
mem2str (buf, "cipher_filter_aead", *ret_len);
}
else if (control == IOBUFCTRL_INIT)
{
write_status_printf (STATUS_BEGIN_ENCRYPTION, "0 %d %d",
cfx->dek->algo, cfx->dek->use_aead);
}
return rc;
}

View File

@ -72,9 +72,6 @@ write_header (cipher_filter_context_t *cfx, iobuf_t a)
log_info (_("Hint: Do not use option %s\n"), "--rfc2440");
}
write_status_printf (STATUS_BEGIN_ENCRYPTION, "%d %d",
ed.mdc_method, cfx->dek->algo);
init_packet (&pkt);
pkt.pkttype = cfx->dek->use_mdc? PKT_ENCRYPTED_MDC : PKT_ENCRYPTED;
pkt.pkt.encrypted = &ed;
@ -182,6 +179,12 @@ cipher_filter_cfb (void *opaque, int control,
{
mem2str (buf, "cipher_filter_cfb", *ret_len);
}
else if (control == IOBUFCTRL_INIT)
{
write_status_printf (STATUS_BEGIN_ENCRYPTION, "%d %d",
cfx->dek->use_mdc ? DIGEST_ALGO_SHA1 : 0,
cfx->dek->algo);
}
return rc;
}

View File

@ -410,8 +410,6 @@ encrypt_simple (const char *filename, int mode, int use_seskey)
text_filter_context_t tfx;
progress_filter_context_t *pfx;
int do_compress = !!default_compress_algo();
char peekbuf[32];
int peekbuflen;
if (!gnupg_rng_is_compliant (opt.compliance))
{
@ -448,14 +446,6 @@ encrypt_simple (const char *filename, int mode, int use_seskey)
return rc;
}
peekbuflen = iobuf_ioctl (inp, IOBUF_IOCTL_PEEK, sizeof peekbuf, peekbuf);
if (peekbuflen < 0)
{
peekbuflen = 0;
if (DBG_FILTER)
log_debug ("peeking at input failed\n");
}
handle_progress (pfx, inp, filename);
if (opt.textmode)
@ -517,17 +507,6 @@ encrypt_simple (const char *filename, int mode, int use_seskey)
/**/ : "CFB");
}
if (do_compress
&& cfx.dek
&& (cfx.dek->use_mdc || cfx.dek->use_aead)
&& !opt.explicit_compress_option
&& is_file_compressed (peekbuf, peekbuflen))
{
if (opt.verbose)
log_info(_("'%s' already compressed\n"), filename? filename: "[stdin]");
do_compress = 0;
}
if ( rc || (rc = open_outfile (-1, filename, opt.armor? 1:0, 0, &out )))
{
iobuf_cancel (inp);
@ -598,6 +577,24 @@ encrypt_simple (const char *filename, int mode, int use_seskey)
else
filesize = opt.set_filesize ? opt.set_filesize : 0; /* stdin */
/* Register the cipher filter. */
if (mode)
iobuf_push_filter (out,
cfx.dek->use_aead? cipher_filter_aead
/**/ : cipher_filter_cfb,
&cfx );
if (do_compress
&& cfx.dek
&& (cfx.dek->use_mdc || cfx.dek->use_aead)
&& !opt.explicit_compress_option
&& is_file_compressed (inp))
{
if (opt.verbose)
log_info(_("'%s' already compressed\n"), filename? filename: "[stdin]");
do_compress = 0;
}
if (!opt.no_literal)
{
/* Note that PT has been initialized above in !no_literal mode. */
@ -617,13 +614,6 @@ encrypt_simple (const char *filename, int mode, int use_seskey)
pkt.pkt.generic = NULL;
}
/* Register the cipher filter. */
if (mode)
iobuf_push_filter (out,
cfx.dek->use_aead? cipher_filter_aead
/**/ : cipher_filter_cfb,
&cfx );
/* Register the compress filter. */
if ( do_compress )
{
@ -783,7 +773,7 @@ encrypt_crypt (ctrl_t ctrl, int filefd, const char *filename,
PKT_plaintext *pt = NULL;
DEK *symkey_dek = NULL;
STRING2KEY *symkey_s2k = NULL;
int rc = 0, rc2 = 0;
int rc = 0;
u32 filesize;
cipher_filter_context_t cfx;
armor_filter_context_t *afx = NULL;
@ -792,8 +782,6 @@ encrypt_crypt (ctrl_t ctrl, int filefd, const char *filename,
progress_filter_context_t *pfx;
PK_LIST pk_list;
int do_compress;
char peekbuf[32];
int peekbuflen;
if (filefd != -1 && filename)
return gpg_error (GPG_ERR_INV_ARG); /* Both given. */
@ -866,14 +854,6 @@ encrypt_crypt (ctrl_t ctrl, int filefd, const char *filename,
if (opt.verbose)
log_info (_("reading from '%s'\n"), iobuf_get_fname_nonnull (inp));
peekbuflen = iobuf_ioctl (inp, IOBUF_IOCTL_PEEK, sizeof peekbuf, peekbuf);
if (peekbuflen < 0)
{
peekbuflen = 0;
if (DBG_FILTER)
log_debug ("peeking at input failed\n");
}
handle_progress (pfx, inp, filename);
if (opt.textmode)
@ -900,25 +880,6 @@ encrypt_crypt (ctrl_t ctrl, int filefd, const char *filename,
if (!cfx.dek->use_aead)
cfx.dek->use_mdc = !!use_mdc (pk_list, cfx.dek->algo);
/* Only do the is-file-already-compressed check if we are using a
* MDC or AEAD. This forces compressed files to be re-compressed if
* we do not have a MDC to give some protection against chosen
* ciphertext attacks. */
if (do_compress
&& (cfx.dek->use_mdc || cfx.dek->use_aead)
&& !opt.explicit_compress_option
&& is_file_compressed (peekbuf, peekbuflen))
{
if (opt.verbose)
log_info(_("'%s' already compressed\n"), filename? filename: "[stdin]");
do_compress = 0;
}
if (rc2)
{
rc = rc2;
goto leave;
}
make_session_key (cfx.dek);
if (DBG_CRYPTO)
log_printhex (cfx.dek->key, cfx.dek->keylen, "DEK is: ");
@ -960,6 +921,26 @@ encrypt_crypt (ctrl_t ctrl, int filefd, const char *filename,
else
filesize = opt.set_filesize ? opt.set_filesize : 0; /* stdin */
/* Register the cipher filter. */
iobuf_push_filter (out,
cfx.dek->use_aead? cipher_filter_aead
/**/ : cipher_filter_cfb,
&cfx);
/* Only do the is-file-already-compressed check if we are using a
* MDC or AEAD. This forces compressed files to be re-compressed if
* we do not have a MDC to give some protection against chosen
* ciphertext attacks. */
if (do_compress
&& (cfx.dek->use_mdc || cfx.dek->use_aead)
&& !opt.explicit_compress_option
&& is_file_compressed (inp))
{
if (opt.verbose)
log_info(_("'%s' already compressed\n"), filename? filename: "[stdin]");
do_compress = 0;
}
if (!opt.no_literal)
{
pt->timestamp = make_timestamp();
@ -974,12 +955,6 @@ encrypt_crypt (ctrl_t ctrl, int filefd, const char *filename,
else
cfx.datalen = filesize && !do_compress ? filesize : 0;
/* Register the cipher filter. */
iobuf_push_filter (out,
cfx.dek->use_aead? cipher_filter_aead
/**/ : cipher_filter_cfb,
&cfx);
/* Register the compress filter. */
if (do_compress)
{

View File

@ -1035,9 +1035,6 @@ sign_file (ctrl_t ctrl, strlist_t filenames, int detached, strlist_t locusr,
int multifile = 0;
u32 duration=0;
pt_extra_hash_data_t extrahash = NULL;
char peekbuf[32];
int peekbuflen = 0;
pfx = new_progress_context ();
afx = new_armor_context ();
@ -1096,14 +1093,6 @@ sign_file (ctrl_t ctrl, strlist_t filenames, int detached, strlist_t locusr,
goto leave;
}
peekbuflen = iobuf_ioctl (inp, IOBUF_IOCTL_PEEK, sizeof peekbuf, peekbuf);
if (peekbuflen < 0)
{
peekbuflen = 0;
if (DBG_FILTER)
log_debug ("peeking at input failed\n");
}
handle_progress (pfx, inp, fname);
}
@ -1261,7 +1250,7 @@ sign_file (ctrl_t ctrl, strlist_t filenames, int detached, strlist_t locusr,
int compr_algo = opt.compress_algo;
if (!opt.explicit_compress_option
&& is_file_compressed (peekbuf, peekbuflen))
&& is_file_compressed (inp))
{
if (opt.verbose)
log_info(_("'%s' already compressed\n"), fname? fname: "[stdin]");