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mirror of git://git.gnupg.org/gnupg.git synced 2024-11-10 21:38:50 +01:00

gpg: New commands --add-recipients and --change-recipients.

* g10/gpg.c (aAddRecipients, aChangeRecipients): New consts.
(opts): Add --add-recipients and --change-recipients.
(main): Handle them.
* g10/gpg.h (struct server_control_s): Add fields modify_recipients,
clear_recipients, and last_read_ctb.
* g10/armor.c (was_armored): New.
* g10/decrypt.c (decrypt_message): Add optional arg 'remusr'.  Handle
re-encryption if desired.
* g10/encrypt.c (write_pubkey_enc): Factor info printing out to ...
(show_encrypted_for_user_info): new.
(reencrypt_to_new_recipients): New.
* g10/packet.h (struct parse_packet_ctx_s): Add fields only_fookey_enc
and last_ctb.
(init_parse_packet): Clear them.
* g10/parse-packet.c (parse): Store CTB in the context.  Early return
on pubkey_enc and symkey_enc packets if requested.
* g10/mainproc.c (proc_encrypted): Allow for PKT being NULL.  Return
early in modify-recipients mode.
(proc_encryption_packets): Add two optional args 'r_dek' and 'r_list'.
Adjust callers.  Call do_proc_packets in modify-recipients mode
depending on the optional args.
(do_proc_packets): Add arg 'keep_dek_and_list'.  Adjust callers.  Save
the last read CTB in CTRL and return after the last fooenc_enc
packets.
--

This basically works but does not yet handle symmetric encrypted
packets (symkey_enc).

GnuPG-bug-id: 1825
(Yes, this is an at least 9 year old feature request)
This commit is contained in:
Werner Koch 2024-09-09 16:41:35 +02:00
parent 2cc340eca0
commit d528d0b065
No known key found for this signature in database
GPG Key ID: E3FDFF218E45B72B
11 changed files with 332 additions and 67 deletions

View File

@ -162,6 +162,14 @@ push_armor_filter (armor_filter_context_t *afx, iobuf_t iobuf)
}
/* This function returns true if the armor filter detected that the
* input was indeed armored. Gives a valid result only after the
* first PGP packet has been read. */
int
was_armored (armor_filter_context_t *afx)
{
return (afx && !afx->inp_bypass);
}

View File

@ -1,6 +1,7 @@
/* decrypt.c - decrypt and verify data
* Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006,
* 2007, 2009 Free Software Foundation, Inc.
* Copyright (C) 2024 g10 Code GmbH
*
* This file is part of GnuPG.
*
@ -16,6 +17,7 @@
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see <https://www.gnu.org/licenses/>.
* SPDX-License-Identifier: GPL-3.0-or-later
*/
#include <config.h>
@ -35,19 +37,26 @@
#include "../common/status.h"
#include "../common/i18n.h"
/* Assume that the input is an encrypted message and decrypt
* (and if signed, verify the signature on) it.
* This command differs from the default operation, as it never
* writes to the filename which is included in the file and it
* rejects files which don't begin with an encrypted message.
*
* REMUSR is only used in the modify_recipients mode and speicifies
* the additional or new recipients to use.
*/
int
decrypt_message (ctrl_t ctrl, const char *filename)
gpg_error_t
decrypt_message (ctrl_t ctrl, const char *filename, strlist_t remusr)
{
IOBUF fp;
gpg_error_t err;
iobuf_t fp;
armor_filter_context_t *afx = NULL;
progress_filter_context_t *pfx;
int rc;
DEK *dek = NULL;
struct pubkey_enc_list *pkenc_list = NULL;
pfx = new_progress_context ();
@ -61,13 +70,17 @@ decrypt_message (ctrl_t ctrl, const char *filename)
}
if ( !fp )
{
rc = gpg_error_from_syserror ();
err = gpg_error_from_syserror ();
log_error (_("can't open '%s': %s\n"), print_fname_stdin(filename),
gpg_strerror (rc));
gpg_strerror (err));
release_progress_context (pfx);
return rc;
return err;
}
/* Push the progress filter unless we are in add recipient mode.
* The latter may also work but for now we better avoid any possible
* complications. */
if (!ctrl->modify_recipients)
handle_progress (pfx, fp, filename);
if ( !opt.no_armor )
@ -86,19 +99,44 @@ decrypt_message (ctrl_t ctrl, const char *filename)
}
else
opt.flags.dummy_outfile = 0;
rc = proc_encryption_packets (ctrl, NULL, fp );
if (!ctrl->modify_recipients)
err = proc_encryption_packets (ctrl, NULL, fp, NULL, NULL);
else
err = proc_encryption_packets (ctrl, NULL, fp, &dek, &pkenc_list);
if (opt.flags.dummy_outfile)
opt.outfile = NULL;
if (ctrl->modify_recipients && (err || !dek) )
log_error (_("modifiying the recipients is not possible: %s\n"),
err? gpg_strerror (err) : _("decryption failed"));
else if (ctrl->modify_recipients)
{
/* We apply an armor to the output if --armor was used or if the
* input was already armored and --no-armor was not given. */
int armor = opt.armor || (was_armored (afx) && !opt.no_armor);
err = reencrypt_to_new_recipients (ctrl, armor, filename, fp,
remusr, dek, pkenc_list);
}
xfree (dek);
while (pkenc_list)
{
struct pubkey_enc_list *tmp = pkenc_list->next;
release_pubkey_enc_parts (&pkenc_list->d);
xfree (pkenc_list);
pkenc_list = tmp;
}
iobuf_close (fp);
release_armor_context (afx);
release_progress_context (pfx);
return rc;
return err;
}
/* Same as decrypt_message but takes a file descriptor for input and
output. */
output. Only used by the unfinished server mode. */
gpg_error_t
decrypt_message_fd (ctrl_t ctrl, gnupg_fd_t input_fd,
gnupg_fd_t output_fd)
@ -173,7 +211,7 @@ decrypt_message_fd (ctrl_t ctrl, gnupg_fd_t input_fd,
}
}
err = proc_encryption_packets (ctrl, NULL, fp );
err = proc_encryption_packets (ctrl, NULL, fp, NULL, NULL);
iobuf_close (fp);
es_fclose (opt.outfp);

View File

@ -46,6 +46,30 @@ static int encrypt_simple( const char *filename, int mode, int use_seskey );
static int write_pubkey_enc_from_list (ctrl_t ctrl,
PK_LIST pk_list, DEK *dek, iobuf_t out);
/* Helper for show the "encrypted for USER" during encryption.
* PUBKEY_USAGE is used to figure out whether this is an ADSK key. */
static void
show_encrypted_for_user_info (ctrl_t ctrl, unsigned int pubkey_usage,
PKT_pubkey_enc *enc, DEK *dek)
{
char *ustr = get_user_id_string_native (ctrl, enc->keyid);
if ((pubkey_usage & PUBKEY_USAGE_RENC))
{
char *tmpustr = xstrconcat (ustr, " [ADSK]", NULL);
xfree (ustr);
ustr = tmpustr;
}
log_info (_("%s/%s.%s encrypted for: \"%s\"\n"),
openpgp_pk_algo_name (enc->pubkey_algo),
openpgp_cipher_algo_name (dek->algo),
dek->use_aead? openpgp_aead_algo_name (dek->use_aead)
/**/ : "CFB",
ustr );
xfree (ustr);
}
/****************
* Encrypt FILENAME with only the symmetric cipher. Take input from
* stdin if FILENAME is NULL. If --force-aead is used we use an SKESK.
@ -389,10 +413,11 @@ use_mdc (pk_list_t pk_list,int algo)
}
/* We don't want to use use_seskey yet because older gnupg versions
can't handle it, and there isn't really any point unless we're
making a message that can be decrypted by a public key or
passphrase. */
/* This function handles the --symmetric only (MODE true) and --store
* (MODE false) cases. We don't want to use USE_SESKEY by default
* very old gnupg versions can't handle it, and there isn't really any
* point unless we're making a message that can be decrypted by a
* public key or passphrase. */
static int
encrypt_simple (const char *filename, int mode, int use_seskey)
{
@ -1034,6 +1059,90 @@ encrypt_crypt (ctrl_t ctrl, gnupg_fd_t filefd, const char *filename,
}
/* Re-encrypt files with a set of new recipients. Note that this
* function is called by decrypt_message. INFP is the iobuf from the
* input file which is positioned right after the pubkey_enc and
* symkey_enc packets. */
gpg_error_t
reencrypt_to_new_recipients (ctrl_t ctrl, int armor, const char *filename,
iobuf_t infp, strlist_t recipients,
DEK *dek, struct pubkey_enc_list *pkenc_list)
{
gpg_error_t err;
int save_no_encrypt_to;
pk_list_t newpk_list = NULL;
iobuf_t outfp = NULL;
armor_filter_context_t *outafx = NULL;
PACKET pkt;
struct pubkey_enc_list *el;
unsigned int count;
/* Get the keys for all additional recipients but do not encrypt to
* the encrypt-to keys. */
save_no_encrypt_to = opt.no_encrypt_to;
opt.no_encrypt_to = 1;
err = build_pk_list (ctrl, recipients, &newpk_list);
opt.no_encrypt_to = save_no_encrypt_to;
if (err)
goto leave;
/* Note that we use by default the suffixes .gpg or .asc */
err = open_outfile (GNUPG_INVALID_FD, filename, armor? 1:0, 0, &outfp);
if (err)
goto leave;
if (armor)
{
outafx = new_armor_context ();
push_armor_filter (outafx, outfp);
}
/* Write the new recipients first. */
err = write_pubkey_enc_from_list (ctrl, newpk_list, dek, outfp);
if (err)
goto leave;
/* The write the old recipients in --add-recipients mode. */
for (count=0, el = pkenc_list; el; el = el->next, count++)
if (!ctrl->clear_recipients)
{
if (opt.verbose)
show_encrypted_for_user_info (ctrl, 0, &el->d, dek);
init_packet (&pkt);
pkt.pkttype = PKT_PUBKEY_ENC;
pkt.pkt.pubkey_enc = &el->d;
err = build_packet (outfp, &pkt);
if (err)
log_error ("build_packet(pubkey_enc) failed: %s\n",
gpg_strerror (err));
}
if (ctrl->clear_recipients && opt.verbose)
log_info (_("number of removed recipients: %u\n"), count);
iobuf_put (outfp, ctrl->last_read_ctb);
/* Finally copy the bulk of the message. */
iobuf_copy (outfp, infp);
if ((err = iobuf_error (infp)))
log_error (_("error reading '%s': %s\n"),
iobuf_get_fname_nonnull (infp), gpg_strerror (err));
else if ((err = iobuf_error (outfp)))
log_error (_("error writing '%s': %s\n"),
iobuf_get_fname_nonnull (outfp), gpg_strerror (err));
leave:
if (err)
iobuf_cancel (outfp);
else
iobuf_close (outfp);
release_armor_context (outafx);
release_pk_list (newpk_list);
return err;
}
/*
* Filter to do a complete public key encryption.
*/
@ -1144,22 +1253,7 @@ write_pubkey_enc (ctrl_t ctrl,
else
{
if ( opt.verbose )
{
char *ustr = get_user_id_string_native (ctrl, enc->keyid);
if ((pk->pubkey_usage & PUBKEY_USAGE_RENC))
{
char *tmpustr = xstrconcat (ustr, " [ADSK]", NULL);
xfree (ustr);
ustr = tmpustr;
}
log_info (_("%s/%s.%s encrypted for: \"%s\"\n"),
openpgp_pk_algo_name (enc->pubkey_algo),
openpgp_cipher_algo_name (dek->algo),
dek->use_aead? openpgp_aead_algo_name (dek->use_aead)
/**/ : "CFB",
ustr );
xfree (ustr);
}
show_encrypted_for_user_info (ctrl, pk->pubkey_usage, enc, dek);
/* And write it. */
init_packet (&pkt);
pkt.pkttype = PKT_PUBKEY_ENC;

View File

@ -175,6 +175,7 @@ void free_md_filter_context( md_filter_context_t *mfx );
armor_filter_context_t *new_armor_context (void);
void release_armor_context (armor_filter_context_t *afx);
int push_armor_filter (armor_filter_context_t *afx, iobuf_t iobuf);
int was_armored (armor_filter_context_t *afx);
int use_armor_filter( iobuf_t a );
/*-- compress.c --*/

View File

@ -115,6 +115,8 @@ enum cmd_and_opt_values
oKnownNotation,
aEncrFiles,
aEncrSym,
aAddRecipients,
aChangeRecipients,
aDecryptFiles,
aClearsign,
aStore,
@ -481,6 +483,8 @@ static gpgrt_opt_t opts[] = {
ARGPARSE_c (aDecryptFiles, "decrypt-files", "@"),
ARGPARSE_c (aVerify, "verify" , N_("verify a signature")),
ARGPARSE_c (aVerifyFiles, "verify-files" , "@" ),
ARGPARSE_c (aAddRecipients, "add-recipients", "@" ),
ARGPARSE_c (aChangeRecipients, "change-recipients", "@" ),
ARGPARSE_c (aListKeys, "list-keys", N_("list keys")),
ARGPARSE_c (aListKeys, "list-public-keys", "@" ),
ARGPARSE_c (aListSigs, "list-signatures", N_("list keys and signatures")),
@ -2739,6 +2743,8 @@ main (int argc, char **argv)
case aExportOwnerTrust:
case aImportOwnerTrust:
case aRebuildKeydbCaches:
case aAddRecipients:
case aChangeRecipients:
set_cmd (&cmd, pargs.r_opt);
break;
@ -4168,6 +4174,12 @@ main (int argc, char **argv)
case aStore:
cmdname="--store";
break;
case aAddRecipients:
cmdname="--add-recipients";
break;
case aChangeRecipients:
cmdname="--change-recipients";
break;
default:
cmdname=NULL;
break;
@ -4262,7 +4274,9 @@ main (int argc, char **argv)
|| cmd == aEncrSym
|| cmd == aSym
|| cmd == aSignSym
|| cmd == aSignEncrSym,
|| cmd == aSignEncrSym
|| cmd == aAddRecipients
|| cmd == aChangeRecipients,
opt.def_cipher_algo,
GCRY_CIPHER_MODE_NONE))
log_error (_("cipher algorithm '%s' may not be used in %s mode\n"),
@ -4509,6 +4523,26 @@ main (int argc, char **argv)
}
break;
case aChangeRecipients: /* Change recipients of the encrypted file. */
ctrl->clear_recipients = 1;
/* fallthru */
case aAddRecipients: /* Add recipients to the encrypted file. */
ctrl->modify_recipients = 1;
if (argc > 1)
{
if (cmd == aAddRecipients)
wrong_args("--add-recipients [filename]");
else
wrong_args("--change-recipients [filename]");
}
if ((rc = decrypt_message (ctrl, fname, remusr)))
{
write_status_failure ("modify-recipients", rc);
log_error ("%s: modify recipients failed: %s\n",
print_fname_stdin (fname), gpg_strerror (rc));
}
break;
case aEncrSym:
/* This works with PGP 8 in the sense that it acts just like a
symmetric message. It doesn't work at all with 2 or 6. It
@ -4650,7 +4684,7 @@ main (int argc, char **argv)
{
if( argc > 1 )
wrong_args("--decrypt [filename]");
if( (rc = decrypt_message (ctrl, fname) ))
if( (rc = decrypt_message (ctrl, fname, NULL) ))
{
write_status_failure ("decrypt", rc);
log_error("decrypt_message failed: %s\n", gpg_strerror (rc) );

View File

@ -122,6 +122,15 @@ struct server_control_s
unsigned char *secret_keygrips;
size_t secret_keygrips_len;
int no_more_secret_keygrips;
/* This first flag is set to true if we are running a
* --add-recipients or --change-recipients command. The second if
* it is --change-recipients. */
unsigned int modify_recipients:1;
unsigned int clear_recipients:1;
/* Temporary used to pass the last read byte up the call chain. */
int last_read_ctb;
};

View File

@ -248,6 +248,11 @@ int encrypt_crypt (ctrl_t ctrl, gnupg_fd_t filefd, const char *filename,
gnupg_fd_t outputfd);
void encrypt_crypt_files (ctrl_t ctrl,
int nfiles, char **files, strlist_t remusr);
gpg_error_t reencrypt_to_new_recipients (ctrl_t ctrl, int armor,
const char *filename, iobuf_t infp,
strlist_t recipients,
DEK *dek,
struct pubkey_enc_list *pkenc_list);
int encrypt_filter (void *opaque, int control,
iobuf_t a, byte *buf, size_t *ret_len);
@ -501,7 +506,8 @@ void check_assert_signer_list (const char *mainpkhex, const char *pkhex);
void check_assert_pubkey_algo (const char *algostr, const char *pkhex);
/*-- decrypt.c --*/
int decrypt_message (ctrl_t ctrl, const char *filename );
gpg_error_t decrypt_message (ctrl_t ctrl, const char *filename,
strlist_t remusr);
gpg_error_t decrypt_message_fd (ctrl_t ctrl, gnupg_fd_t input_fd,
gnupg_fd_t output_fd);
void decrypt_messages (ctrl_t ctrl, int nfiles, char *files[]);

View File

@ -116,7 +116,7 @@ static int literals_seen;
/*** Local prototypes. ***/
static int do_proc_packets (CTX c, iobuf_t a);
static int do_proc_packets (CTX c, iobuf_t a, int keep_dek_and_list);
static void list_node (CTX c, kbnode_t node);
static void proc_tree (CTX c, kbnode_t node);
@ -580,10 +580,15 @@ proc_encrypted (CTX c, PACKET *pkt)
int early_plaintext = literals_seen;
unsigned int compliance_de_vs = 0;
if (pkt)
{
if (pkt->pkttype == PKT_ENCRYPTED_AEAD)
c->seen_pkt_encrypted_aead = 1;
if (pkt->pkttype == PKT_ENCRYPTED_MDC)
c->seen_pkt_encrypted_mdc = 1;
}
else /* No PKT indicates the the add-recipients mode. */
log_assert (c->ctrl->modify_recipients);
if (early_plaintext)
{
@ -650,6 +655,22 @@ proc_encrypted (CTX c, PACKET *pkt)
if (c->dek && opt.verbose > 1)
log_info (_("public key encrypted data: good DEK\n"));
if (c->ctrl->modify_recipients)
{
if (c->anchor)
{
log_error ("command not possible with nested data\n");
write_status_errcode ("decryption.mod_recp", GPG_ERR_BAD_DATA);
xfree (c->dek);
c->dek = NULL;
return;
}
literals_seen++;
/* Simply return here. Our caller will then test for DEK and
* the PK_list to decide whether decryption worked. */
return;
}
if (!opt.show_only_session_key)
write_status (STATUS_BEGIN_DECRYPTION);
@ -1112,7 +1133,7 @@ static int
proc_encrypt_cb (iobuf_t a, void *info )
{
CTX c = info;
return proc_encryption_packets (c->ctrl, info, a );
return proc_encryption_packets (c->ctrl, info, a, NULL, NULL);
}
@ -1502,7 +1523,7 @@ proc_packets (ctrl_t ctrl, void *anchor, iobuf_t a )
c->ctrl = ctrl;
c->anchor = anchor;
rc = do_proc_packets (c, a);
rc = do_proc_packets (c, a, 0);
xfree (c);
return rc;
@ -1525,7 +1546,7 @@ proc_signature_packets (ctrl_t ctrl, void *anchor, iobuf_t a,
c->signed_data.used = !!signedfiles;
c->sigfilename = sigfilename;
rc = do_proc_packets (c, a);
rc = do_proc_packets (c, a, 0);
/* If we have not encountered any signature we print an error
messages, send a NODATA status back and return an error code.
@ -1568,7 +1589,7 @@ proc_signature_packets_by_fd (ctrl_t ctrl, void *anchor, iobuf_t a,
c->signed_data.data_names = NULL;
c->signed_data.used = (signed_data_fd != GNUPG_INVALID_FD);
rc = do_proc_packets (c, a);
rc = do_proc_packets (c, a, 0);
/* If we have not encountered any signature we print an error
messages, send a NODATA status back and return an error code.
@ -1592,8 +1613,13 @@ proc_signature_packets_by_fd (ctrl_t ctrl, void *anchor, iobuf_t a,
}
int
proc_encryption_packets (ctrl_t ctrl, void *anchor, iobuf_t a )
/* Handle encryption packets. If called recursively the caller's CTX
* should be given for ANCHOR. If R_DEK and R_LIST are not NULL the
* DEK (or NULL) is returned there and the list at R_LIST; the caller
* needs to release them; even if the function returns an error. */
gpg_error_t
proc_encryption_packets (ctrl_t ctrl, void *anchor, iobuf_t a,
DEK **r_dek, struct pubkey_enc_list **r_list)
{
CTX c = xmalloc_clear (sizeof *c);
int rc;
@ -1601,7 +1627,16 @@ proc_encryption_packets (ctrl_t ctrl, void *anchor, iobuf_t a )
c->ctrl = ctrl;
c->anchor = anchor;
c->encrypt_only = 1;
rc = do_proc_packets (c, a);
if (r_dek && r_list)
{
rc = do_proc_packets (c, a, 1);
*r_dek = c->dek;
c->dek = NULL;
*r_list = c->pkenc_list;
c->pkenc_list = NULL;
}
else
rc = do_proc_packets (c, a, 0);
xfree (c);
return rc;
}
@ -1626,8 +1661,11 @@ check_nesting (CTX c)
}
/* Main processing loop. If KEEP_DEK_AND_LIST is set the DEK and
* PKENC_LIST of the context C are not released at the end of the
* function. The caller is then required to do this. */
static int
do_proc_packets (CTX c, iobuf_t a)
do_proc_packets (CTX c, iobuf_t a, int keep_dek_and_list)
{
PACKET *pkt;
struct parse_packet_ctx_s parsectx;
@ -1648,6 +1686,18 @@ do_proc_packets (CTX c, iobuf_t a)
any_data = 1;
if (rc)
{
if (c->ctrl->modify_recipients && gpg_err_code (rc) == GPG_ERR_TRUE)
{
/* Save the last read CTB (which was the last byte
* actually read from the input) and get out of the
* loop. */
c->ctrl->last_read_ctb = parsectx.last_ctb;
/* We need to call the first part of the encrypted data
* handler to get the DEK. */
proc_encrypted (c, NULL);
rc = -1;
break;
}
free_packet (pkt, &parsectx);
/* Stop processing when an invalid packet has been encountered
* but don't do so when we are doing a --list-packets. */
@ -1706,8 +1756,19 @@ do_proc_packets (CTX c, iobuf_t a)
goto leave;
case PKT_SIGNATURE: newpkt = add_signature (c, pkt); break;
case PKT_SYMKEY_ENC: proc_symkey_enc (c, pkt); break;
case PKT_PUBKEY_ENC: proc_pubkey_enc (c, pkt); break;
case PKT_SYMKEY_ENC:
case PKT_PUBKEY_ENC:
/* In --add-recipients mode set the stop flag as soon as
* we see the first of these packets. */
if (c->ctrl->modify_recipients)
parsectx.only_fookey_enc = 1;
if (pkt->pkttype == PKT_SYMKEY_ENC)
proc_symkey_enc (c, pkt);
else
proc_pubkey_enc (c, pkt);
break;
case PKT_ENCRYPTED:
case PKT_ENCRYPTED_MDC:
case PKT_ENCRYPTED_AEAD: proc_encrypted (c, pkt); break;
@ -1783,8 +1844,8 @@ do_proc_packets (CTX c, iobuf_t a)
leave:
if (!keep_dek_and_list)
release_list (c);
xfree(c->dek);
free_packet (pkt, &parsectx);
deinit_parse_packet (&parsectx);
xfree (pkt);

View File

@ -165,7 +165,7 @@ ask_outfile_name( const char *name, size_t namelen )
/*
* Make an output filename for the inputfile INAME.
* Returns an IOBUF and an errorcode
* Returns an IOBUF at A and an errorcode
* Mode 0 = use ".gpg"
* 1 = use ".asc"
* 2 = use ".sig"

View File

@ -644,7 +644,10 @@ int proc_signature_packets (ctrl_t ctrl, void *ctx, iobuf_t a,
strlist_t signedfiles, const char *sigfile );
int proc_signature_packets_by_fd (ctrl_t ctrl, void *anchor, IOBUF a,
gnupg_fd_t signed_data_fd);
int proc_encryption_packets (ctrl_t ctrl, void *ctx, iobuf_t a);
gpg_error_t proc_encryption_packets (ctrl_t ctrl, void *ctx, iobuf_t a,
DEK **r_dek,
struct pubkey_enc_list **r_list);
int list_packets( iobuf_t a );
const byte *issuer_fpr_raw (PKT_signature *sig, size_t *r_len);
@ -673,7 +676,9 @@ struct parse_packet_ctx_s
struct packet_struct last_pkt; /* The last parsed packet. */
int free_last_pkt; /* Indicates that LAST_PKT must be freed. */
int skip_meta; /* Skip ring trust packets. */
int only_fookey_enc; /* Stop if the packet is not {sym,pub}key_enc. */
unsigned int n_parsed_packets; /* Number of parsed packets. */
int last_ctb; /* The last CTB read. */
};
typedef struct parse_packet_ctx_s *parse_packet_ctx_t;
@ -683,7 +688,9 @@ typedef struct parse_packet_ctx_s *parse_packet_ctx_t;
(a)->last_pkt.pkt.generic= NULL;\
(a)->free_last_pkt = 0; \
(a)->skip_meta = 0; \
(a)->only_fookey_enc = 0; \
(a)->n_parsed_packets = 0; \
(a)->last_ctb = 1; \
} while (0)
#define deinit_parse_packet(a) do { \

View File

@ -763,6 +763,7 @@ parse (parse_packet_ctx_t ctx, PACKET *pkt, int onlykeypkts, off_t * retpos,
rc = -1;
goto leave;
}
ctx->last_ctb = ctb;
hdrlen = 0;
hdr[hdrlen++] = ctb;
@ -774,18 +775,28 @@ parse (parse_packet_ctx_t ctx, PACKET *pkt, int onlykeypkts, off_t * retpos,
}
/* Immediately following the header is the length. There are two
formats: the old format and the new format. If bit 6 (where the
least significant bit is bit 0) is set in the tag, then we are
dealing with a new format packet. Otherwise, it is an old format
packet. */
* formats: the old format and the new format. If bit 6 (where the
* least significant bit is bit 0) is set in the tag, then we are
* dealing with a new format packet. Otherwise, it is an old format
* packet. In the new format the packet's type is encoded in the 6
* least significant bits of the tag; in the old format it is
* encoded in bits 2-5. */
pktlen = 0;
new_ctb = !!(ctb & 0x40);
if (new_ctb)
{
/* Get the packet's type. This is encoded in the 6 least
significant bits of the tag. */
pkttype = ctb & 0x3f;
else
pkttype = (ctb >> 2) & 0xf;
if (ctx->only_fookey_enc
&& !(pkttype == PKT_SYMKEY_ENC || pkttype == PKT_PUBKEY_ENC))
{
rc = gpg_error (GPG_ERR_TRUE);
goto leave;
}
if (new_ctb)
{
/* Extract the packet's length. New format packets have 4 ways
to encode the packet length. The value of the first byte
determines the encoding and partially determines the length.
@ -855,12 +866,8 @@ parse (parse_packet_ctx_t ctx, PACKET *pkt, int onlykeypkts, off_t * retpos,
}
}
else
/* This is an old format packet. */
else /* This is an old format packet. */
{
/* Extract the packet's type. This is encoded in bits 2-5. */
pkttype = (ctb >> 2) & 0xf;
/* The type of length encoding is encoded in bits 0-1 of the
tag. */
lenbytes = ((ctb & 3) == 3) ? 0 : (1 << (ctb & 3));