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indent: Improve readability of some comments in getkey.c 

--

Signed-off-by: Werner Koch <wk@gnupg.org>
This commit is contained in:
Werner Koch 2017-07-20 18:35:46 +02:00
parent 165cdd8121
commit a5dcc01a73
No known key found for this signature in database
GPG Key ID: E3FDFF218E45B72B
1 changed files with 168 additions and 165 deletions
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333
g10/getkey.c
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@ -2491,32 +2491,32 @@ sig_to_revoke_info (PKT_signature * sig, struct revoke_info *rinfo)
/* Given a keyblock, parse the key block and extract various pieces of
information and save them with the primary key packet and the user
id packets. For instance, some information is stored in signature
packets. We find the latest such valid packet (since the user can
change that information) and copy its contents into the
PKT_public_key.
Note that R_REVOKED may be set to 0, 1 or 2.
This function fills in the following fields in the primary key's
keyblock:
main_keyid (computed)
revkey / numrevkeys (derived from self signed key data)
flags.valid (whether we have at least 1 self-sig)
flags.maybe_revoked (whether a designed revoked the key, but
we are missing the key to check the sig)
selfsigversion (highest version of any valid self-sig)
pubkey_usage (derived from most recent self-sig or most
recent user id)
has_expired (various sources)
expiredate (various sources)
See the documentation for fixup_uidnode for how the user id packets
are modified. In addition to that the primary user id's is_primary
field is set to 1 and the other user id's is_primary are set to
0. */
* information and save them with the primary key packet and the user
* id packets. For instance, some information is stored in signature
* packets. We find the latest such valid packet (since the user can
* change that information) and copy its contents into the
* PKT_public_key.
*
* Note that R_REVOKED may be set to 0, 1 or 2.
*
* This function fills in the following fields in the primary key's
* keyblock:
*
* main_keyid (computed)
* revkey / numrevkeys (derived from self signed key data)
* flags.valid (whether we have at least 1 self-sig)
* flags.maybe_revoked (whether a designed revoked the key, but
* we are missing the key to check the sig)
* selfsigversion (highest version of any valid self-sig)
* pubkey_usage (derived from most recent self-sig or most
* recent user id)
* has_expired (various sources)
* expiredate (various sources)
*
* See the documentation for fixup_uidnode for how the user id packets
* are modified. In addition to that the primary user id's is_primary
* field is set to 1 and the other user id's is_primary are set to 0.
*/
static void
merge_selfsigs_main (ctrl_t ctrl, kbnode_t keyblock, int *r_revoked,
struct revoke_info *rinfo)
@ -2537,17 +2537,16 @@ merge_selfsigs_main (ctrl_t ctrl, kbnode_t keyblock, int *r_revoked,
memset (rinfo, 0, sizeof (*rinfo));
/* Section 11.1 of RFC 4880 determines the order of packets within a
message. There are three sections, which must occur in the
following order: the public key, the user ids and user attributes
and the subkeys. Within each section, each primary packet (e.g.,
a user id packet) is followed by one or more signature packets,
which modify that packet. */
* message. There are three sections, which must occur in the
* following order: the public key, the user ids and user attributes
* and the subkeys. Within each section, each primary packet (e.g.,
* a user id packet) is followed by one or more signature packets,
* which modify that packet. */
/* According to Section 11.1 of RFC 4880, the public key must be the
first packet. */
first packet. Note that parse_keyblock_image ensures that the
first packet is the public key. */
if (keyblock->pkt->pkttype != PKT_PUBLIC_KEY)
/* parse_keyblock_image ensures that the first packet is the
public key. */
BUG ();
pk = keyblock->pkt->pkt.public_key;
keytimestamp = pk->timestamp;
@ -2566,16 +2565,16 @@ merge_selfsigs_main (ctrl_t ctrl, kbnode_t keyblock, int *r_revoked,
}
/* First pass:
- Find the latest direct key self-signature. We assume that the
newest one overrides all others.
- Determine whether the key has been revoked.
- Gather all revocation keys (unlike other data, we don't just
take them from the latest self-signed packet).
- Determine max (sig[...]->version).
*
* - Find the latest direct key self-signature. We assume that the
* newest one overrides all others.
*
* - Determine whether the key has been revoked.
*
* - Gather all revocation keys (unlike other data, we don't just
* take them from the latest self-signed packet).
*
* - Determine max (sig[...]->version).
*/
/* Reset this in case this key was already merged. */
@ -2587,8 +2586,8 @@ merge_selfsigs_main (ctrl_t ctrl, kbnode_t keyblock, int *r_revoked,
sigdate = 0; /* Helper variable to find the latest signature. */
/* According to Section 11.1 of RFC 4880, the public key comes first
and is immediately followed by any signature packets that modify
it. */
* and is immediately followed by any signature packets that modify
* it. */
for (k = keyblock;
k && k->pkt->pkttype != PKT_USER_ID
&& k->pkt->pkttype != PKT_ATTRIBUTE
@ -2599,8 +2598,8 @@ merge_selfsigs_main (ctrl_t ctrl, kbnode_t keyblock, int *r_revoked,
{
PKT_signature *sig = k->pkt->pkt.signature;
if (sig->keyid[0] == kid[0] && sig->keyid[1] == kid[1])
/* Self sig. */
{
{ /* Self sig. */
if (check_key_signature (ctrl, keyblock, k, NULL))
; /* Signature did not verify. */
else if (IS_KEY_REV (sig))
@ -2620,11 +2619,11 @@ merge_selfsigs_main (ctrl_t ctrl, kbnode_t keyblock, int *r_revoked,
else if (IS_KEY_SIG (sig))
{
/* Add the indicated revocations keys from all
signatures not just the latest. We do this
because you need multiple 1F sigs to properly
handle revocation keys (PGP does it this way, and
a revocation key could be sensitive and hence in
a different signature). */
* signatures not just the latest. We do this
* because you need multiple 1F sigs to properly
* handle revocation keys (PGP does it this way, and
* a revocation key could be sensitive and hence in
* a different signature). */
if (sig->revkey)
{
int i;
@ -2640,8 +2639,8 @@ merge_selfsigs_main (ctrl_t ctrl, kbnode_t keyblock, int *r_revoked,
}
if (sig->timestamp >= sigdate)
/* This is the latest signature so far. */
{
{ /* This is the latest signature so far. */
if (sig->flags.expired)
; /* Signature has expired - ignore it. */
else
@ -2688,9 +2687,9 @@ merge_selfsigs_main (ctrl_t ctrl, kbnode_t keyblock, int *r_revoked,
sizeof (struct revocation_key));
}
/* SIGNODE is the 1F signature packet with the latest creation time.
* Extract some information from it. */
if (signode)
/* SIGNODE is the 1F signature packet with the latest creation
time. Extract some information from it. */
{
/* Some information from a direct key signature take precedence
* over the same information given in UID sigs. */
@ -2712,9 +2711,9 @@ merge_selfsigs_main (ctrl_t ctrl, kbnode_t keyblock, int *r_revoked,
}
/* Pass 1.5: Look for key revocation signatures that were not made
by the key (i.e. did a revocation key issue a revocation for
us?). Only bother to do this if there is a revocation key in the
first place and we're not revoked already. */
* by the key (i.e. did a revocation key issue a revocation for
* us?). Only bother to do this if there is a revocation key in the
* first place and we're not revoked already. */
if (!*r_revoked && pk->revkey)
for (k = keyblock; k && k->pkt->pkttype != PKT_USER_ID; k = k->next)
@ -2732,20 +2731,20 @@ merge_selfsigs_main (ctrl_t ctrl, kbnode_t keyblock, int *r_revoked,
*r_revoked = 2;
sig_to_revoke_info (sig, rinfo);
/* Don't continue checking since we can't be any
more revoked than this. */
* more revoked than this. */
break;
}
else if (gpg_err_code (rc) == GPG_ERR_NO_PUBKEY)
pk->flags.maybe_revoked = 1;
/* A failure here means the sig did not verify, was
not issued by a revocation key, or a revocation
key loop was broken. If a revocation key isn't
findable, however, the key might be revoked and
we don't know it. */
* not issued by a revocation key, or a revocation
* key loop was broken. If a revocation key isn't
* findable, however, the key might be revoked and
* we don't know it. */
/* TODO: In the future handle subkey and cert
revocations? PGP doesn't, but it's in 2440. */
/* Fixme: In the future handle subkey and cert
* revocations? PGP doesn't, but it's in 2440. */
}
}
}
@ -2753,28 +2752,30 @@ merge_selfsigs_main (ctrl_t ctrl, kbnode_t keyblock, int *r_revoked,
/* Second pass: Look at the self-signature of all user IDs. */
/* According to RFC 4880 section 11.1, user id and attribute packets
are in the second section, after the public key packet and before
the subkey packets. */
* are in the second section, after the public key packet and before
* the subkey packets. */
signode = uidnode = NULL;
sigdate = 0; /* Helper variable to find the latest signature in one UID. */
for (k = keyblock; k && k->pkt->pkttype != PKT_PUBLIC_SUBKEY; k = k->next)
{
if (k->pkt->pkttype == PKT_USER_ID || k->pkt->pkttype == PKT_ATTRIBUTE)
/* New user id packet. */
{
{ /* New user id packet. */
/* Apply the data from the most recent self-signed packet to
* the preceding user id packet. */
if (uidnode && signode)
/* Apply the data from the most recent self-signed packet
to the preceding user id packet. */
{
fixup_uidnode (uidnode, signode, keytimestamp);
pk->flags.valid = 1;
}
/* Clear SIGNODE. The only relevant self-signed data for
UIDNODE follows it. */
* UIDNODE follows it. */
if (k->pkt->pkttype == PKT_USER_ID)
uidnode = k;
else
uidnode = NULL;
signode = NULL;
sigdate = 0;
}
@ -2812,7 +2813,7 @@ merge_selfsigs_main (ctrl_t ctrl, kbnode_t keyblock, int *r_revoked,
}
/* If the key isn't valid yet, and we have
--allow-non-selfsigned-uid set, then force it valid. */
* --allow-non-selfsigned-uid set, then force it valid. */
if (!pk->flags.valid && opt.allow_non_selfsigned_uid)
{
if (opt.verbose)
@ -2822,7 +2823,7 @@ merge_selfsigs_main (ctrl_t ctrl, kbnode_t keyblock, int *r_revoked,
}
/* The key STILL isn't valid, so try and find an ultimately
trusted signature. */
* trusted signature. */
if (!pk->flags.valid)
{
uidnode = NULL;
@ -2842,12 +2843,11 @@ merge_selfsigs_main (ctrl_t ctrl, kbnode_t keyblock, int *r_revoked,
ultimate_pk = xmalloc_clear (sizeof (*ultimate_pk));
/* We don't want to use the full get_pubkey to
avoid infinite recursion in certain cases.
There is no reason to check that an ultimately
trusted key is still valid - if it has been
revoked the user should also remove the
ultimate trust flag. */
/* We don't want to use the full get_pubkey to avoid
* infinite recursion in certain cases. There is no
* reason to check that an ultimately trusted key is
* still valid - if it has been revoked the user
* should also remove the ultimate trust flag. */
if (get_pubkey_fast (ultimate_pk, sig->keyid) == 0
&& check_key_signature2 (ctrl,
keyblock, k, ultimate_pk,
@ -2865,20 +2865,18 @@ merge_selfsigs_main (ctrl_t ctrl, kbnode_t keyblock, int *r_revoked,
}
}
/* Record the highest selfsig version so we know if this is a v3
key through and through, or a v3 key with a v4 selfsig
somewhere. This is useful in a few places to know if the key
must be treated as PGP2-style or OpenPGP-style. Note that a
selfsig revocation with a higher version number will also raise
this value. This is okay since such a revocation must be
issued by the user (i.e. it cannot be issued by someone else to
modify the key behavior.) */
/* Record the highest selfsig version so we know if this is a v3 key
* through and through, or a v3 key with a v4 selfsig somewhere.
* This is useful in a few places to know if the key must be treated
* as PGP2-style or OpenPGP-style. Note that a selfsig revocation
* with a higher version number will also raise this value. This is
* okay since such a revocation must be issued by the user (i.e. it
* cannot be issued by someone else to modify the key behavior.) */
pk->selfsigversion = sigversion;
/* Now that we had a look at all user IDs we can now get some information
* from those user IDs.
*/
/* Now that we had a look at all user IDs we can now get some
* information from those user IDs. */
if (!key_usage)
{
@ -2890,6 +2888,7 @@ merge_selfsigs_main (ctrl_t ctrl, kbnode_t keyblock, int *r_revoked,
if (k->pkt->pkttype == PKT_USER_ID)
{
PKT_user_id *uid = k->pkt->pkt.user_id;
if (uid->help_key_usage && uid->created > uiddate)
{
key_usage = uid->help_key_usage;
@ -2898,6 +2897,7 @@ merge_selfsigs_main (ctrl_t ctrl, kbnode_t keyblock, int *r_revoked,
}
}
}
if (!key_usage)
{
/* No key flags at all: get it from the algo. */
@ -2936,7 +2936,7 @@ merge_selfsigs_main (ctrl_t ctrl, kbnode_t keyblock, int *r_revoked,
}
/* Currently only v3 keys have a maximum expiration date, but I'll
bet v5 keys get this feature again. */
* bet v5 keys get this feature again. */
if (key_expire == 0
|| (pk->max_expiredate && key_expire > pk->max_expiredate))
key_expire = pk->max_expiredate;
@ -2944,8 +2944,8 @@ merge_selfsigs_main (ctrl_t ctrl, kbnode_t keyblock, int *r_revoked,
pk->has_expired = key_expire >= curtime ? 0 : key_expire;
pk->expiredate = key_expire;
/* Fixme: we should see how to get rid of the expiretime fields but
* this needs changes at other places too. */
/* Fixme: we should see how to get rid of the expiretime fields but
* this needs changes at other places too. */
/* And now find the real primary user ID and delete all others. */
uiddate = uiddate2 = 0;
@ -2964,12 +2964,11 @@ merge_selfsigs_main (ctrl_t ctrl, kbnode_t keyblock, int *r_revoked,
}
else if (uid->created == uiddate && uidnode)
{
/* The dates are equal, so we need to do a
different (and arbitrary) comparison. This
should rarely, if ever, happen. It's good to
try and guarantee that two different GnuPG
users with two different keyrings at least pick
the same primary. */
/* The dates are equal, so we need to do a different
* (and arbitrary) comparison. This should rarely,
* if ever, happen. It's good to try and guarantee
* that two different GnuPG users with two different
* keyrings at least pick the same primary. */
if (cmp_user_ids (uid, uidnode->pkt->pkt.user_id) > 0)
uidnode = k;
}
@ -3006,14 +3005,14 @@ merge_selfsigs_main (ctrl_t ctrl, kbnode_t keyblock, int *r_revoked,
else if (uidnode2)
{
/* None is flagged primary - use the latest user ID we have,
and disambiguate with the arbitrary packet comparison. */
* and disambiguate with the arbitrary packet comparison. */
uidnode2->pkt->pkt.user_id->flags.primary = 1;
}
else
{
/* None of our uids were self-signed, so pick the one that
sorts first to be the primary. This is the best we can do
here since there are no self sigs to date the uids. */
* sorts first to be the primary. This is the best we can do
* here since there are no self sigs to date the uids. */
uidnode = NULL;
@ -3039,16 +3038,19 @@ merge_selfsigs_main (ctrl_t ctrl, kbnode_t keyblock, int *r_revoked,
uidnode->pkt->pkt.user_id->flags.primary = 1;
}
else
k->pkt->pkt.user_id->flags.primary = 0; /* just to be
safe */
{
/* just to be safe: */
k->pkt->pkt.user_id->flags.primary = 0;
}
}
}
}
}
}
/* Convert a buffer to a signature. Useful for 0x19 embedded sigs.
Caller must free the signature when they are done. */
* Caller must free the signature when they are done. */
static PKT_signature *
buf_to_sig (const byte * buf, size_t len)
{
@ -3068,25 +3070,26 @@ buf_to_sig (const byte * buf, size_t len)
return sig;
}
/* Use the self-signed data to fill in various fields in subkeys.
KEYBLOCK is the whole keyblock. SUBNODE is the subkey to fill in.
Sets the following fields on the subkey:
main_keyid
flags.valid if the subkey has a valid self-sig binding
flags.revoked
flags.backsig
pubkey_usage
has_expired
expired_date
On this subkey's most revent valid self-signed packet, the
following field is set:
flags.chosen_selfsig
*/
*
* KEYBLOCK is the whole keyblock. SUBNODE is the subkey to fill in.
*
* Sets the following fields on the subkey:
*
* main_keyid
* flags.valid if the subkey has a valid self-sig binding
* flags.revoked
* flags.backsig
* pubkey_usage
* has_expired
* expired_date
*
* On this subkey's most revent valid self-signed packet, the
* following field is set:
*
* flags.chosen_selfsig
*/
static void
merge_selfsigs_subkey (ctrl_t ctrl, kbnode_t keyblock, kbnode_t subnode)
{
@ -3132,13 +3135,13 @@ merge_selfsigs_subkey (ctrl_t ctrl, kbnode_t keyblock, kbnode_t subnode)
else if (IS_SUBKEY_REV (sig))
{
/* Note that this means that the date on a
revocation sig does not matter - even if the
binding sig is dated after the revocation sig,
the subkey is still marked as revoked. This
seems ok, as it is just as easy to make new
subkeys rather than re-sign old ones as the
problem is in the distribution. Plus, PGP (7)
does this the same way. */
* revocation sig does not matter - even if the
* binding sig is dated after the revocation sig,
* the subkey is still marked as revoked. This
* seems ok, as it is just as easy to make new
* subkeys rather than re-sign old ones as the
* problem is in the distribution. Plus, PGP (7)
* does this the same way. */
subpk->flags.revoked = 1;
sig_to_revoke_info (sig, &subpk->revoked);
/* Although we could stop now, we continue to
@ -3188,6 +3191,7 @@ merge_selfsigs_subkey (ctrl_t ctrl, kbnode_t keyblock, kbnode_t subnode)
key_expire = keytimestamp + buf32_to_u32 (p);
else
key_expire = 0;
subpk->has_expired = key_expire >= curtime ? 0 : key_expire;
subpk->expiredate = key_expire;
@ -3207,7 +3211,7 @@ merge_selfsigs_subkey (ctrl_t ctrl, kbnode_t keyblock, kbnode_t subnode)
sigdate = 0;
/* We do this while() since there may be other embedded
signatures in the future. We only want 0x19 here. */
* signatures in the future. We only want 0x19 here. */
while ((p = enum_sig_subpkt (sig->hashed,
SIGSUBPKT_SIGNATURE, &n, &seq, NULL)))
@ -3233,7 +3237,7 @@ merge_selfsigs_subkey (ctrl_t ctrl, kbnode_t keyblock, kbnode_t subnode)
seq = 0;
/* It is safe to have this in the unhashed area since the 0x19
is located on the selfsig for convenience, not security. */
* is located on the selfsig for convenience, not security. */
while ((p = enum_sig_subpkt (sig->unhashed, SIGSUBPKT_SIGNATURE,
&n, &seq, NULL)))
@ -3259,7 +3263,7 @@ merge_selfsigs_subkey (ctrl_t ctrl, kbnode_t keyblock, kbnode_t subnode)
if (backsig)
{
/* At this point, backsig contains the most recent 0x19 sig.
Let's see if it is good. */
* Let's see if it is good. */
/* 2==valid, 1==invalid, 0==didn't check */
if (check_backsig (mainpk, subpk, backsig) == 0)
@ -3274,10 +3278,10 @@ merge_selfsigs_subkey (ctrl_t ctrl, kbnode_t keyblock, kbnode_t subnode)
/* Merge information from the self-signatures with the public key,
subkeys and user ids to make using them more easy.
See documentation for merge_selfsigs_main, merge_selfsigs_subkey
and fixup_uidnode for exactly which fields are updated. */
* subkeys and user ids to make using them more easy.
*
* See documentation for merge_selfsigs_main, merge_selfsigs_subkey
* and fixup_uidnode for exactly which fields are updated. */
static void
merge_selfsigs (ctrl_t ctrl, kbnode_t keyblock)
{
@ -3295,8 +3299,8 @@ merge_selfsigs (ctrl_t ctrl, kbnode_t keyblock)
log_error ("expected public key but found secret key "
"- must stop\n");
/* We better exit here because a public key is expected at
other places too. FIXME: Figure this out earlier and
don't get to here at all */
* other places too. FIXME: Figure this out earlier and
* don't get to here at all */
g10_exit (1);
}
BUG ();
@ -3691,22 +3695,22 @@ print_status_key_considered (kbnode_t keyblock, unsigned int flags)
/* A high-level function to lookup keys.
This function builds on top of the low-level keydb API. It first
searches the database using the description stored in CTX->ITEMS,
then it filters the results using CTX and, finally, if WANT_SECRET
is set, it ignores any keys for which no secret key is available.
Unlike the low-level search functions, this function also merges
all of the self-signed data into the keys, subkeys and user id
packets (see the merge_selfsigs for details).
On success the key's keyblock is stored at *RET_KEYBLOCK, and the
specific subkey is stored at *RET_FOUND_KEY. Note that we do not
return a reference in *RET_FOUND_KEY, i.e. the result must not be
freed using 'release_kbnode', and it is only valid until
*RET_KEYBLOCK is deallocated. Therefore, if RET_FOUND_KEY is not
NULL, then RET_KEYBLOCK must not be NULL. */
*
* This function builds on top of the low-level keydb API. It first
* searches the database using the description stored in CTX->ITEMS,
* then it filters the results using CTX and, finally, if WANT_SECRET
* is set, it ignores any keys for which no secret key is available.
*
* Unlike the low-level search functions, this function also merges
* all of the self-signed data into the keys, subkeys and user id
* packets (see the merge_selfsigs for details).
*
* On success the key's keyblock is stored at *RET_KEYBLOCK, and the
* specific subkey is stored at *RET_FOUND_KEY. Note that we do not
* return a reference in *RET_FOUND_KEY, i.e. the result must not be
* freed using 'release_kbnode', and it is only valid until
* *RET_KEYBLOCK is deallocated. Therefore, if RET_FOUND_KEY is not
* NULL, then RET_KEYBLOCK must not be NULL. */
static int
lookup (ctrl_t ctrl, getkey_ctx_t ctx, int want_secret,
kbnode_t *ret_keyblock, kbnode_t *ret_found_key)
@ -3728,9 +3732,8 @@ lookup (ctrl_t ctrl, getkey_ctx_t ctx, int want_secret,
break;
/* If we are iterating over the entire database, then we need to
change from KEYDB_SEARCH_MODE_FIRST, which does an implicit
reset, to KEYDB_SEARCH_MODE_NEXT, which gets the next
record. */
* change from KEYDB_SEARCH_MODE_FIRST, which does an implicit
* reset, to KEYDB_SEARCH_MODE_NEXT, which gets the next record. */
if (ctx->nitems && ctx->items->mode == KEYDB_SEARCH_MODE_FIRST)
ctx->items->mode = KEYDB_SEARCH_MODE_NEXT;
@ -3771,10 +3774,10 @@ lookup (ctrl_t ctrl, getkey_ctx_t ctx, int want_secret,
release_kbnode (keyblock);
keyblock = NULL;
/* The keyblock cache ignores the current "file position".
Thus, if we request the next result and the cache matches
(and it will since it is what we just looked for), we'll get
the same entry back! We can avoid this infinite loop by
disabling the cache. */
* Thus, if we request the next result and the cache matches
* (and it will since it is what we just looked for), we'll get
* the same entry back! We can avoid this infinite loop by
* disabling the cache. */
keydb_disable_caching (ctx->kr_handle);
}