626 lines
24 KiB
Diff
626 lines
24 KiB
Diff
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From da0164efc7f32013bc24d97b9afa9f8d67c318bb Mon Sep 17 00:00:00 2001
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From: Werner Koch <wk@gnupg.org>
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Date: Fri, 21 Feb 2025 12:16:17 +0100
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Subject: [PATCH] gpg: Fix a verification DoS due to a malicious subkey in the
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keyring.
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* g10/getkey.c (get_pubkey): Factor code out to ...
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(get_pubkey_bykid): new. Add feature to return the keyblock.
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(get_pubkey_for_sig): Add arg r_keyblock to return the used keyblock.
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Request a signing usage.
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(get_pubkeyblock_for_sig): Remove.
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(finish_lookup): Improve debug output.
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* g10/sig-check.c (check_signature): Add arg r_keyblock and pass it
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down.
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* g10/mainproc.c (do_check_sig): Ditto.
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(check_sig_and_print): Use the keyblock returned by do_check_sig to
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show further information instead of looking it up again with
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get_pubkeyblock_for_sig. Also re-check the signature after the import
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of an included keyblock.
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--
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The problem here is that it is possible to import a key from someone
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who added a signature subkey from another public key and thus inhibits
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that a good signature good be verified.
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Such a malicious key signature subkey must have been created w/o the
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mandatory backsig which bind a signature subkey to its primary key.
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For encryption subkeys this is not an issue because the existence of a
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decryption private key is all you need to decrypt something and then
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it does not matter if the public subkey or its binding signature has
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been put below another primary key; in fact we do the latter for
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ADSKs.
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GnuPG-bug-id: 7527
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Backported-from-master: 48978ccb4e20866472ef18436a32744350a65158
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---
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g10/getkey.c | 108 ++++++++++++++++++++++++++++++------------------
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g10/gpg.h | 3 +-
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g10/keydb.h | 10 ++++-
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g10/mainproc.c | 92 ++++++++++++++++++++++++++---------------
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g10/packet.h | 2 +-
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g10/sig-check.c | 23 +++++++----
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6 files changed, 152 insertions(+), 86 deletions(-)
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diff --git a/g10/getkey.c b/g10/getkey.c
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index 20ae84332..c4d02fbb1 100644
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--- a/g10/getkey.c
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+++ b/g10/getkey.c
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@@ -316,27 +316,50 @@ pk_from_block (PKT_public_key *pk, kbnode_t keyblock, kbnode_t found_key)
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/* Specialized version of get_pubkey which retrieves the key based on
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* information in SIG. In contrast to get_pubkey PK is required. IF
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- * FORCED_PK is not NULL, this public key is used and copied to PK. */
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+ * FORCED_PK is not NULL, this public key is used and copied to PK.
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+ * If R_KEYBLOCK is not NULL the entire keyblock is stored there if
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+ * found and FORCED_PK is not used; if not used or on error NULL is
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+ * stored there. */
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gpg_error_t
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get_pubkey_for_sig (ctrl_t ctrl, PKT_public_key *pk, PKT_signature *sig,
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- PKT_public_key *forced_pk)
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+ PKT_public_key *forced_pk, kbnode_t *r_keyblock)
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{
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+ gpg_error_t err;
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const byte *fpr;
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size_t fprlen;
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+ if (r_keyblock)
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+ *r_keyblock = NULL;
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+
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if (forced_pk)
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{
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copy_public_key (pk, forced_pk);
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return 0;
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}
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+ /* Make sure to request only keys cabable of signing. This makes
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+ * sure that a subkey w/o a valid backsig or with bad usage flags
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+ * will be skipped. */
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+ pk->req_usage = PUBKEY_USAGE_SIG;
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+
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/* First try the ISSUER_FPR info. */
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fpr = issuer_fpr_raw (sig, &fprlen);
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- if (fpr && !get_pubkey_byfprint (ctrl, pk, NULL, fpr, fprlen))
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+ if (fpr && !get_pubkey_byfprint (ctrl, pk, r_keyblock, fpr, fprlen))
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return 0;
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+ if (r_keyblock)
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+ {
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+ release_kbnode (*r_keyblock);
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+ *r_keyblock = NULL;
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+ }
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/* Fallback to use the ISSUER_KEYID. */
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- return get_pubkey (ctrl, pk, sig->keyid);
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+ err = get_pubkey_bykid (ctrl, pk, r_keyblock, sig->keyid);
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+ if (err && r_keyblock)
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+ {
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+ release_kbnode (*r_keyblock);
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+ *r_keyblock = NULL;
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+ }
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+ return err;
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}
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@@ -354,6 +377,10 @@ get_pubkey_for_sig (ctrl_t ctrl, PKT_public_key *pk, PKT_signature *sig,
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* usage will be returned. As such, it is essential that
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* PK->REQ_USAGE be correctly initialized!
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*
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+ * If R_KEYBLOCK is not NULL, then the first result's keyblock is
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+ * returned in *R_KEYBLOCK. This should be freed using
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+ * release_kbnode().
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+ *
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* Returns 0 on success, GPG_ERR_NO_PUBKEY if there is no public key
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* with the specified key id, or another error code if an error
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* occurs.
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@@ -361,24 +388,30 @@ get_pubkey_for_sig (ctrl_t ctrl, PKT_public_key *pk, PKT_signature *sig,
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* If the data was not read from the cache, then the self-signed data
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* has definitely been merged into the public key using
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* merge_selfsigs. */
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-int
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-get_pubkey (ctrl_t ctrl, PKT_public_key * pk, u32 * keyid)
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+gpg_error_t
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+get_pubkey_bykid (ctrl_t ctrl, PKT_public_key *pk, kbnode_t *r_keyblock,
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+ u32 *keyid)
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{
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int internal = 0;
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- int rc = 0;
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+ gpg_error_t rc = 0;
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+
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+ if (r_keyblock)
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+ *r_keyblock = NULL;
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#if MAX_PK_CACHE_ENTRIES
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- if (pk)
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+ if (pk && !r_keyblock)
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{
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/* Try to get it from the cache. We don't do this when pk is
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- NULL as it does not guarantee that the user IDs are
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- cached. */
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+ * NULL as it does not guarantee that the user IDs are cached.
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+ * The old get_pubkey_function did not check PK->REQ_USAGE when
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+ * reading form the caceh. This is probably a bug. Note that
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+ * the cache is not used when the caller asked to return the
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+ * entire keyblock. This is because the cache does not
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+ * associate the public key wit its primary key. */
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pk_cache_entry_t ce;
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for (ce = pk_cache; ce; ce = ce->next)
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{
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if (ce->keyid[0] == keyid[0] && ce->keyid[1] == keyid[1])
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- /* XXX: We don't check PK->REQ_USAGE here, but if we don't
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- read from the cache, we do check it! */
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{
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copy_public_key (pk, ce->pk);
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return 0;
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@@ -386,6 +419,7 @@ get_pubkey (ctrl_t ctrl, PKT_public_key * pk, u32 * keyid)
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}
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}
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#endif
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+
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/* More init stuff. */
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if (!pk)
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{
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@@ -431,16 +465,18 @@ get_pubkey (ctrl_t ctrl, PKT_public_key * pk, u32 * keyid)
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ctx.req_usage = pk->req_usage;
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rc = lookup (ctrl, &ctx, 0, &kb, &found_key);
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if (!rc)
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+ pk_from_block (pk, kb, found_key);
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+ getkey_end (ctrl, &ctx);
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+ if (!rc && r_keyblock)
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{
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- pk_from_block (pk, kb, found_key);
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+ *r_keyblock = kb;
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+ kb = NULL;
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}
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- getkey_end (ctrl, &ctx);
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release_kbnode (kb);
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}
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- if (!rc)
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- goto leave;
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- rc = GPG_ERR_NO_PUBKEY;
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+ if (rc) /* Return a more useful error code. */
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+ rc = gpg_error (GPG_ERR_NO_PUBKEY);
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leave:
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if (!rc)
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@@ -451,6 +487,14 @@ leave:
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}
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+/* Wrapper for get_pubkey_bykid w/o keyblock return feature. */
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+int
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+get_pubkey (ctrl_t ctrl, PKT_public_key *pk, u32 *keyid)
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+{
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+ return get_pubkey_bykid (ctrl, pk, NULL, keyid);
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+}
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+
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+
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/* Same as get_pubkey but if the key was not found the function tries
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* to import it from LDAP. FIXME: We should not need this but swicth
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* to a fingerprint lookup. */
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@@ -563,28 +607,6 @@ get_pubkey_fast (ctrl_t ctrl, PKT_public_key * pk, u32 * keyid)
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}
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-/* Return the entire keyblock used to create SIG. This is a
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- * specialized version of get_pubkeyblock.
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- *
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- * FIXME: This is a hack because get_pubkey_for_sig was already called
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- * and it could have used a cache to hold the key. */
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-kbnode_t
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-get_pubkeyblock_for_sig (ctrl_t ctrl, PKT_signature *sig)
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-{
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- const byte *fpr;
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- size_t fprlen;
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- kbnode_t keyblock;
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-
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- /* First try the ISSUER_FPR info. */
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- fpr = issuer_fpr_raw (sig, &fprlen);
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- if (fpr && !get_pubkey_byfprint (ctrl, NULL, &keyblock, fpr, fprlen))
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- return keyblock;
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-
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- /* Fallback to use the ISSUER_KEYID. */
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- return get_pubkeyblock (ctrl, sig->keyid);
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-}
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-
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-
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/* Return the key block for the key with key id KEYID or NULL, if an
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* error occurs. Use release_kbnode() to release the key block.
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*
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@@ -3701,6 +3723,7 @@ finish_lookup (kbnode_t keyblock, unsigned int req_usage, int want_exact,
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kbnode_t latest_key;
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PKT_public_key *pk;
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int req_prim;
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+ int diag_exactfound = 0;
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u32 curtime = make_timestamp ();
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if (r_flags)
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@@ -3731,11 +3754,10 @@ finish_lookup (kbnode_t keyblock, unsigned int req_usage, int want_exact,
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{
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if (want_exact)
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{
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- if (DBG_LOOKUP)
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- log_debug ("finish_lookup: exact search requested and found\n");
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foundk = k;
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pk = k->pkt->pkt.public_key;
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pk->flags.exact = 1;
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+ diag_exactfound = 1;
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break;
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}
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else if ((k->pkt->pkt.public_key->pubkey_usage == PUBKEY_USAGE_RENC))
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@@ -3765,10 +3787,14 @@ finish_lookup (kbnode_t keyblock, unsigned int req_usage, int want_exact,
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log_debug ("finish_lookup: checking key %08lX (%s)(req_usage=%x)\n",
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(ulong) keyid_from_pk (keyblock->pkt->pkt.public_key, NULL),
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foundk ? "one" : "all", req_usage);
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+ if (diag_exactfound && DBG_LOOKUP)
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+ log_debug ("\texact search requested and found\n");
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if (!req_usage)
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{
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latest_key = foundk ? foundk : keyblock;
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+ if (DBG_LOOKUP)
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+ log_debug ("\tno usage requested - accepting key\n");
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goto found;
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}
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diff --git a/g10/gpg.h b/g10/gpg.h
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index c51bbbb46..0cdcb8b12 100644
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--- a/g10/gpg.h
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+++ b/g10/gpg.h
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@@ -69,7 +69,8 @@ struct dirmngr_local_s;
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typedef struct dirmngr_local_s *dirmngr_local_t;
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/* Object used to describe a keyblock node. */
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-typedef struct kbnode_struct *KBNODE; /* Deprecated use kbnode_t. */typedef struct kbnode_struct *kbnode_t;
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+typedef struct kbnode_struct *KBNODE; /* Deprecated use kbnode_t. */
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+typedef struct kbnode_struct *kbnode_t;
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/* The handle for keydb operations. */
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typedef struct keydb_handle_s *KEYDB_HANDLE;
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diff --git a/g10/keydb.h b/g10/keydb.h
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index 658c85a29..7d25b3550 100644
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--- a/g10/keydb.h
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+++ b/g10/keydb.h
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@@ -332,9 +332,15 @@ void getkey_disable_caches(void);
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/* Return the public key used for signature SIG and store it at PK. */
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gpg_error_t get_pubkey_for_sig (ctrl_t ctrl,
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PKT_public_key *pk, PKT_signature *sig,
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- PKT_public_key *forced_pk);
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+ PKT_public_key *forced_pk,
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+ kbnode_t *r_keyblock);
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-/* Return the public key with the key id KEYID and store it at PK. */
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+/* Return the public key with the key id KEYID and store it at PK.
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+ * Optionally return the entire keyblock. */
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+gpg_error_t get_pubkey_bykid (ctrl_t ctrl, PKT_public_key *pk,
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+ kbnode_t *r_keyblock, u32 *keyid);
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+
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+/* Same as get_pubkey_bykid but w/o r_keyblock. */
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int get_pubkey (ctrl_t ctrl, PKT_public_key *pk, u32 *keyid);
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/* Same as get_pubkey but with auto LDAP fetch. */
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diff --git a/g10/mainproc.c b/g10/mainproc.c
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index 86f5a2db9..308738839 100644
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--- a/g10/mainproc.c
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+++ b/g10/mainproc.c
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@@ -1150,12 +1150,15 @@ proc_compressed (CTX c, PACKET *pkt)
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* used to verify the signature will be stored there, or NULL if not
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* found. If FORCED_PK is not NULL, this public key is used to verify
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* _data signatures_ and no key lookup is done. Returns: 0 = valid
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- * signature or an error code
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+ * signature or an error code. If R_KEYBLOCK is not NULL the keyblock
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+ * carries the used PK is stored there. The caller should always free
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+ * the return value using release_kbnode.
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*/
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static int
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do_check_sig (CTX c, kbnode_t node, const void *extrahash, size_t extrahashlen,
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PKT_public_key *forced_pk, int *is_selfsig,
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- int *is_expkey, int *is_revkey, PKT_public_key **r_pk)
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+ int *is_expkey, int *is_revkey,
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+ PKT_public_key **r_pk, kbnode_t *r_keyblock)
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{
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PKT_signature *sig;
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gcry_md_hd_t md = NULL;
|
||
|
|
@@ -1165,6 +1168,8 @@ do_check_sig (CTX c, kbnode_t node, const void *extrahash, size_t extrahashlen,
|
||
|
|
|
||
|
|
if (r_pk)
|
||
|
|
*r_pk = NULL;
|
||
|
|
+ if (r_keyblock)
|
||
|
|
+ *r_keyblock = NULL;
|
||
|
|
|
||
|
|
log_assert (node->pkt->pkttype == PKT_SIGNATURE);
|
||
|
|
if (is_selfsig)
|
||
|
|
@@ -1241,16 +1246,19 @@ do_check_sig (CTX c, kbnode_t node, const void *extrahash, size_t extrahashlen,
|
||
|
|
/* We only get here if we are checking the signature of a binary
|
||
|
|
(0x00) or text document (0x01). */
|
||
|
|
rc = check_signature (c->ctrl, sig, md, extrahash, extrahashlen,
|
||
|
|
- forced_pk, NULL, is_expkey, is_revkey, r_pk);
|
||
|
|
+ forced_pk, NULL, is_expkey, is_revkey,
|
||
|
|
+ r_pk, r_keyblock);
|
||
|
|
if (! rc)
|
||
|
|
md_good = md;
|
||
|
|
else if (gpg_err_code (rc) == GPG_ERR_BAD_SIGNATURE && md2)
|
||
|
|
{
|
||
|
|
PKT_public_key *pk2;
|
||
|
|
|
||
|
|
+ if (r_keyblock)
|
||
|
|
+ release_kbnode (*r_keyblock);
|
||
|
|
rc = check_signature (c->ctrl, sig, md2, extrahash, extrahashlen,
|
||
|
|
forced_pk, NULL, is_expkey, is_revkey,
|
||
|
|
- r_pk? &pk2 : NULL);
|
||
|
|
+ r_pk? &pk2 : NULL, r_keyblock);
|
||
|
|
if (!rc)
|
||
|
|
{
|
||
|
|
md_good = md2;
|
||
|
|
@@ -1413,7 +1421,7 @@ list_node (CTX c, kbnode_t node)
|
||
|
|
{
|
||
|
|
fflush (stdout);
|
||
|
|
rc2 = do_check_sig (c, node, NULL, 0, NULL,
|
||
|
|
- &is_selfsig, NULL, NULL, NULL);
|
||
|
|
+ &is_selfsig, NULL, NULL, NULL, NULL);
|
||
|
|
switch (gpg_err_code (rc2))
|
||
|
|
{
|
||
|
|
case 0: sigrc = '!'; break;
|
||
|
|
@@ -1872,7 +1880,7 @@ check_sig_and_print (CTX c, kbnode_t node)
|
||
|
|
PKT_public_key *pk = NULL; /* The public key for the signature or NULL. */
|
||
|
|
const void *extrahash = NULL;
|
||
|
|
size_t extrahashlen = 0;
|
||
|
|
- kbnode_t included_keyblock = NULL;
|
||
|
|
+ kbnode_t keyblock = NULL;
|
||
|
|
|
||
|
|
if (opt.skip_verify)
|
||
|
|
{
|
||
|
|
@@ -1993,7 +2001,8 @@ check_sig_and_print (CTX c, kbnode_t node)
|
||
|
|
{
|
||
|
|
ambiguous:
|
||
|
|
log_error(_("can't handle this ambiguous signature data\n"));
|
||
|
|
- return 0;
|
||
|
|
+ rc = 0;
|
||
|
|
+ goto leave;
|
||
|
|
}
|
||
|
|
} /* End checking signature packet composition. */
|
||
|
|
|
||
|
|
@@ -2029,7 +2038,7 @@ check_sig_and_print (CTX c, kbnode_t node)
|
||
|
|
log_info (_(" issuer \"%s\"\n"), sig->signers_uid);
|
||
|
|
|
||
|
|
rc = do_check_sig (c, node, extrahash, extrahashlen, NULL,
|
||
|
|
- NULL, &is_expkey, &is_revkey, &pk);
|
||
|
|
+ NULL, &is_expkey, &is_revkey, &pk, &keyblock);
|
||
|
|
|
||
|
|
/* If the key is not found but the signature includes a key block we
|
||
|
|
* use that key block for verification and on success import it. */
|
||
|
|
@@ -2037,6 +2046,7 @@ check_sig_and_print (CTX c, kbnode_t node)
|
||
|
|
&& sig->flags.key_block
|
||
|
|
&& opt.flags.auto_key_import)
|
||
|
|
{
|
||
|
|
+ kbnode_t included_keyblock = NULL;
|
||
|
|
PKT_public_key *included_pk;
|
||
|
|
const byte *kblock;
|
||
|
|
size_t kblock_len;
|
||
|
|
@@ -2048,10 +2058,12 @@ check_sig_and_print (CTX c, kbnode_t node)
|
||
|
|
kblock+1, kblock_len-1,
|
||
|
|
sig->keyid, &included_keyblock))
|
||
|
|
{
|
||
|
|
+ /* Note: This is the only place where we use the forced_pk
|
||
|
|
+ * arg (ie. included_pk) with do_check_sig. */
|
||
|
|
rc = do_check_sig (c, node, extrahash, extrahashlen, included_pk,
|
||
|
|
- NULL, &is_expkey, &is_revkey, &pk);
|
||
|
|
+ NULL, &is_expkey, &is_revkey, &pk, NULL);
|
||
|
|
if (opt.verbose)
|
||
|
|
- log_debug ("checked signature using included key block: %s\n",
|
||
|
|
+ log_info ("checked signature using included key block: %s\n",
|
||
|
|
gpg_strerror (rc));
|
||
|
|
if (!rc)
|
||
|
|
{
|
||
|
|
@@ -2061,6 +2073,18 @@ check_sig_and_print (CTX c, kbnode_t node)
|
||
|
|
|
||
|
|
}
|
||
|
|
free_public_key (included_pk);
|
||
|
|
+ release_kbnode (included_keyblock);
|
||
|
|
+
|
||
|
|
+ /* To make sure that nothing strange happened we check the
|
||
|
|
+ * signature again now using our own key store. This also
|
||
|
|
+ * returns the keyblock which we use later on. */
|
||
|
|
+ if (!rc)
|
||
|
|
+ {
|
||
|
|
+ release_kbnode (keyblock);
|
||
|
|
+ keyblock = NULL;
|
||
|
|
+ rc = do_check_sig (c, node, extrahash, extrahashlen, NULL,
|
||
|
|
+ NULL, &is_expkey, &is_revkey, &pk, &keyblock);
|
||
|
|
+ }
|
||
|
|
}
|
||
|
|
|
||
|
|
/* If the key isn't found, check for a preferred keyserver. Note
|
||
|
|
@@ -2107,8 +2131,13 @@ check_sig_and_print (CTX c, kbnode_t node)
|
||
|
|
KEYSERVER_IMPORT_FLAG_QUICK);
|
||
|
|
glo_ctrl.in_auto_key_retrieve--;
|
||
|
|
if (!res)
|
||
|
|
- rc = do_check_sig (c, node, extrahash, extrahashlen, NULL,
|
||
|
|
- NULL, &is_expkey, &is_revkey, &pk);
|
||
|
|
+ {
|
||
|
|
+ release_kbnode (keyblock);
|
||
|
|
+ keyblock = NULL;
|
||
|
|
+ rc = do_check_sig (c, node, extrahash, extrahashlen, NULL,
|
||
|
|
+ NULL, &is_expkey, &is_revkey, &pk,
|
||
|
|
+ &keyblock);
|
||
|
|
+ }
|
||
|
|
else if (DBG_LOOKUP)
|
||
|
|
log_debug ("lookup via %s failed: %s\n", "Pref-KS",
|
||
|
|
gpg_strerror (res));
|
||
|
|
@@ -2149,8 +2178,12 @@ check_sig_and_print (CTX c, kbnode_t node)
|
||
|
|
/* Fixme: If the fingerprint is embedded in the signature,
|
||
|
|
* compare it to the fingerprint of the returned key. */
|
||
|
|
if (!res)
|
||
|
|
- rc = do_check_sig (c, node, extrahash, extrahashlen, NULL,
|
||
|
|
- NULL, &is_expkey, &is_revkey, &pk);
|
||
|
|
+ {
|
||
|
|
+ release_kbnode (keyblock);
|
||
|
|
+ keyblock = NULL;
|
||
|
|
+ rc = do_check_sig (c, node, extrahash, extrahashlen, NULL,
|
||
|
|
+ NULL, &is_expkey, &is_revkey, &pk, &keyblock);
|
||
|
|
+ }
|
||
|
|
else if (DBG_LOOKUP)
|
||
|
|
log_debug ("lookup via %s failed: %s\n", "WKD", gpg_strerror (res));
|
||
|
|
}
|
||
|
|
@@ -2180,8 +2213,13 @@ check_sig_and_print (CTX c, kbnode_t node)
|
||
|
|
KEYSERVER_IMPORT_FLAG_QUICK);
|
||
|
|
glo_ctrl.in_auto_key_retrieve--;
|
||
|
|
if (!res)
|
||
|
|
- rc = do_check_sig (c, node, extrahash, extrahashlen, NULL,
|
||
|
|
- NULL, &is_expkey, &is_revkey, &pk);
|
||
|
|
+ {
|
||
|
|
+ release_kbnode (keyblock);
|
||
|
|
+ keyblock = NULL;
|
||
|
|
+ rc = do_check_sig (c, node, extrahash, extrahashlen, NULL,
|
||
|
|
+ NULL, &is_expkey, &is_revkey, &pk,
|
||
|
|
+ &keyblock);
|
||
|
|
+ }
|
||
|
|
else if (DBG_LOOKUP)
|
||
|
|
log_debug ("lookup via %s failed: %s\n", "KS", gpg_strerror (res));
|
||
|
|
}
|
||
|
|
@@ -2192,7 +2230,7 @@ check_sig_and_print (CTX c, kbnode_t node)
|
||
|
|
{
|
||
|
|
/* We have checked the signature and the result is either a good
|
||
|
|
* signature or a bad signature. Further examination follows. */
|
||
|
|
- kbnode_t un, keyblock;
|
||
|
|
+ kbnode_t un;
|
||
|
|
int count = 0;
|
||
|
|
int keyblock_has_pk = 0; /* For failsafe check. */
|
||
|
|
int statno;
|
||
|
|
@@ -2210,18 +2248,6 @@ check_sig_and_print (CTX c, kbnode_t node)
|
||
|
|
else
|
||
|
|
statno = STATUS_GOODSIG;
|
||
|
|
|
||
|
|
- /* FIXME: We should have the public key in PK and thus the
|
||
|
|
- * keyblock has already been fetched. Thus we could use the
|
||
|
|
- * fingerprint or PK itself to lookup the entire keyblock. That
|
||
|
|
- * would best be done with a cache. */
|
||
|
|
- if (included_keyblock)
|
||
|
|
- {
|
||
|
|
- keyblock = included_keyblock;
|
||
|
|
- included_keyblock = NULL;
|
||
|
|
- }
|
||
|
|
- else
|
||
|
|
- keyblock = get_pubkeyblock_for_sig (c->ctrl, sig);
|
||
|
|
-
|
||
|
|
snprintf (keyid_str, sizeof keyid_str, "%08lX%08lX [uncertain] ",
|
||
|
|
(ulong)sig->keyid[0], (ulong)sig->keyid[1]);
|
||
|
|
|
||
|
|
@@ -2287,10 +2313,10 @@ check_sig_and_print (CTX c, kbnode_t node)
|
||
|
|
* contained in the keyring.*/
|
||
|
|
}
|
||
|
|
|
||
|
|
- log_assert (mainpk);
|
||
|
|
- if (!keyblock_has_pk)
|
||
|
|
+ if (!mainpk || !keyblock_has_pk)
|
||
|
|
{
|
||
|
|
- log_error ("signature key lost from keyblock\n");
|
||
|
|
+ log_error ("signature key lost from keyblock (%p,%p,%d)\n",
|
||
|
|
+ keyblock, mainpk, keyblock_has_pk);
|
||
|
|
rc = gpg_error (GPG_ERR_INTERNAL);
|
||
|
|
}
|
||
|
|
|
||
|
|
@@ -2562,8 +2588,8 @@ check_sig_and_print (CTX c, kbnode_t node)
|
||
|
|
log_error (_("Can't check signature: %s\n"), gpg_strerror (rc));
|
||
|
|
}
|
||
|
|
|
||
|
|
+ leave:
|
||
|
|
free_public_key (pk);
|
||
|
|
- release_kbnode (included_keyblock);
|
||
|
|
xfree (issuer_fpr);
|
||
|
|
return rc;
|
||
|
|
}
|
||
|
|
diff --git a/g10/packet.h b/g10/packet.h
|
||
|
|
index b61c65417..d6cbef4bc 100644
|
||
|
|
--- a/g10/packet.h
|
||
|
|
+++ b/g10/packet.h
|
||
|
|
@@ -917,7 +917,7 @@ gpg_error_t check_signature (ctrl_t ctrl,
|
||
|
|
const void *extrahash, size_t extrahashlen,
|
||
|
|
PKT_public_key *forced_pk,
|
||
|
|
u32 *r_expiredate, int *r_expired, int *r_revoked,
|
||
|
|
- PKT_public_key **r_pk);
|
||
|
|
+ PKT_public_key **r_pk, kbnode_t *r_keyblock);
|
||
|
|
|
||
|
|
|
||
|
|
/*-- pubkey-enc.c --*/
|
||
|
|
diff --git a/g10/sig-check.c b/g10/sig-check.c
|
||
|
|
index 54db2089a..456c29320 100644
|
||
|
|
--- a/g10/sig-check.c
|
||
|
|
+++ b/g10/sig-check.c
|
||
|
|
@@ -131,6 +131,11 @@ check_key_verify_compliance (PKT_public_key *pk)
|
||
|
|
* If R_PK is not NULL, the public key is stored at that address if it
|
||
|
|
* was found; other wise NULL is stored.
|
||
|
|
*
|
||
|
|
+ * If R_KEYBLOCK is not NULL, the entire keyblock used to verify the
|
||
|
|
+ * signature is stored at that address. If no key was found or on
|
||
|
|
+ * some other errors NULL is stored there. The callers needs to
|
||
|
|
+ * release the keyblock using release_kbnode (kb).
|
||
|
|
+ *
|
||
|
|
* Returns 0 on success. An error code otherwise. */
|
||
|
|
gpg_error_t
|
||
|
|
check_signature (ctrl_t ctrl,
|
||
|
|
@@ -138,7 +143,7 @@ check_signature (ctrl_t ctrl,
|
||
|
|
const void *extrahash, size_t extrahashlen,
|
||
|
|
PKT_public_key *forced_pk,
|
||
|
|
u32 *r_expiredate, int *r_expired, int *r_revoked,
|
||
|
|
- PKT_public_key **r_pk)
|
||
|
|
+ PKT_public_key **r_pk, kbnode_t *r_keyblock)
|
||
|
|
{
|
||
|
|
int rc=0;
|
||
|
|
PKT_public_key *pk;
|
||
|
|
@@ -151,6 +156,8 @@ check_signature (ctrl_t ctrl,
|
||
|
|
*r_revoked = 0;
|
||
|
|
if (r_pk)
|
||
|
|
*r_pk = NULL;
|
||
|
|
+ if (r_keyblock)
|
||
|
|
+ *r_keyblock = NULL;
|
||
|
|
|
||
|
|
pk = xtrycalloc (1, sizeof *pk);
|
||
|
|
if (!pk)
|
||
|
|
@@ -181,7 +188,7 @@ check_signature (ctrl_t ctrl,
|
||
|
|
log_info(_("WARNING: signature digest conflict in message\n"));
|
||
|
|
rc = gpg_error (GPG_ERR_GENERAL);
|
||
|
|
}
|
||
|
|
- else if (get_pubkey_for_sig (ctrl, pk, sig, forced_pk))
|
||
|
|
+ else if (get_pubkey_for_sig (ctrl, pk, sig, forced_pk, r_keyblock))
|
||
|
|
rc = gpg_error (GPG_ERR_NO_PUBKEY);
|
||
|
|
else if ((rc = check_key_verify_compliance (pk)))
|
||
|
|
;/* Compliance failure. */
|
||
|
|
@@ -780,9 +787,9 @@ check_revocation_keys (ctrl_t ctrl, PKT_public_key *pk, PKT_signature *sig)
|
||
|
|
keyid_from_fingerprint (ctrl, pk->revkey[i].fpr, pk->revkey[i].fprlen,
|
||
|
|
keyid);
|
||
|
|
|
||
|
|
- if(keyid[0]==sig->keyid[0] && keyid[1]==sig->keyid[1])
|
||
|
|
- /* The signature was generated by a designated revoker.
|
||
|
|
- Verify the signature. */
|
||
|
|
+ /* If the signature was generated by a designated revoker
|
||
|
|
+ * verify the signature. */
|
||
|
|
+ if (keyid[0] == sig->keyid[0] && keyid[1] == sig->keyid[1])
|
||
|
|
{
|
||
|
|
gcry_md_hd_t md;
|
||
|
|
|
||
|
|
@@ -790,9 +797,9 @@ check_revocation_keys (ctrl_t ctrl, PKT_public_key *pk, PKT_signature *sig)
|
||
|
|
BUG ();
|
||
|
|
hash_public_key(md,pk);
|
||
|
|
/* Note: check_signature only checks that the signature
|
||
|
|
- is good. It does not fail if the key is revoked. */
|
||
|
|
+ * is good. It does not fail if the key is revoked. */
|
||
|
|
rc = check_signature (ctrl, sig, md, NULL, 0, NULL,
|
||
|
|
- NULL, NULL, NULL, NULL);
|
||
|
|
+ NULL, NULL, NULL, NULL, NULL);
|
||
|
|
cache_sig_result(sig,rc);
|
||
|
|
gcry_md_close (md);
|
||
|
|
break;
|
||
|
|
@@ -997,7 +1004,7 @@ check_signature_over_key_or_uid (ctrl_t ctrl, PKT_public_key *signer,
|
||
|
|
if (IS_CERT (sig))
|
||
|
|
signer->req_usage = PUBKEY_USAGE_CERT;
|
||
|
|
|
||
|
|
- rc = get_pubkey_for_sig (ctrl, signer, sig, NULL);
|
||
|
|
+ rc = get_pubkey_for_sig (ctrl, signer, sig, NULL, NULL);
|
||
|
|
if (rc)
|
||
|
|
{
|
||
|
|
xfree (signer);
|
||
|
|
--
|
||
|
|
2.33.0
|
||
|
|
|