diff options
| -rw-r--r-- | g10/mainproc.c | 130 | ||||
| -rw-r--r-- | g10/packet.h | 14 | ||||
| -rw-r--r-- | g10/sig-check.c | 58 |
3 files changed, 111 insertions, 91 deletions
diff --git a/g10/mainproc.c b/g10/mainproc.c index f861a3ea2..716363f4c 100644 --- a/g10/mainproc.c +++ b/g10/mainproc.c @@ -839,12 +839,13 @@ proc_compressed (CTX c, PACKET *pkt) /* - * check the signature - * Returns: 0 = valid signature or an error code + * Check the signature. If R_PK is not NULL a copy of the public key + * used to verify the signature will be stored tehre, or NULL if not + * found. Returns: 0 = valid signature or an error code */ static int do_check_sig (CTX c, kbnode_t node, int *is_selfsig, - int *is_expkey, int *is_revkey) + int *is_expkey, int *is_revkey, PKT_public_key **r_pk) { PKT_signature *sig; gcry_md_hd_t md = NULL; @@ -852,6 +853,9 @@ do_check_sig (CTX c, kbnode_t node, int *is_selfsig, gcry_md_hd_t md_good = NULL; int algo, rc; + if (r_pk) + *r_pk = NULL; + log_assert (node->pkt->pkttype == PKT_SIGNATURE); if (is_selfsig) *is_selfsig = 0; @@ -926,14 +930,24 @@ do_check_sig (CTX c, kbnode_t node, int *is_selfsig, /* We only get here if we are checking the signature of a binary (0x00) or text document (0x01). */ - rc = check_signature2 (sig, md, NULL, is_expkey, is_revkey, NULL); + rc = check_signature2 (sig, md, NULL, is_expkey, is_revkey, r_pk); if (! rc) md_good = md; else if (gpg_err_code (rc) == GPG_ERR_BAD_SIGNATURE && md2) { - rc = check_signature2 (sig, md2, NULL, is_expkey, is_revkey, NULL); - if (! rc) - md_good = md2; + PKT_public_key *pk2; + + rc = check_signature2 (sig, md2, NULL, is_expkey, is_revkey, + r_pk? &pk2 : NULL); + if (!rc) + { + md_good = md2; + if (r_pk) + { + free_public_key (*r_pk); + *r_pk = pk2; + } + } } if (md_good) @@ -1096,7 +1110,7 @@ list_node (CTX c, kbnode_t node) if (opt.check_sigs) { fflush (stdout); - rc2 = do_check_sig (c, node, &is_selfsig, NULL, NULL); + rc2 = do_check_sig (c, node, &is_selfsig, NULL, NULL, NULL); switch (gpg_err_code (rc2)) { case 0: sigrc = '!'; break; @@ -1603,10 +1617,8 @@ check_sig_and_print (CTX c, kbnode_t node) int rc; int is_expkey = 0; int is_revkey = 0; - char pkstrbuf[PUBKEY_STRING_SIZE]; char *issuer_fpr; - - *pkstrbuf = 0; + PKT_public_key *pk = NULL; /* The public key for the signature or NULL. */ if (opt.skip_verify) { @@ -1754,7 +1766,7 @@ check_sig_and_print (CTX c, kbnode_t node) if (sig->signers_uid) log_info (_(" issuer \"%s\"\n"), sig->signers_uid); - rc = do_check_sig (c, node, NULL, &is_expkey, &is_revkey ); + rc = do_check_sig (c, node, NULL, &is_expkey, &is_revkey, &pk); /* If the key isn't found, check for a preferred keyserver. */ if (gpg_err_code (rc) == GPG_ERR_NO_PUBKEY && sig->flags.pref_ks) @@ -1783,11 +1795,14 @@ check_sig_and_print (CTX c, kbnode_t node) { int res; + free_public_key (pk); + pk = NULL; glo_ctrl.in_auto_key_retrieve++; res = keyserver_import_keyid (c->ctrl, sig->keyid,spec); glo_ctrl.in_auto_key_retrieve--; if (!res) - rc = do_check_sig(c, node, NULL, &is_expkey, &is_revkey ); + rc = do_check_sig (c, node, NULL, + &is_expkey, &is_revkey, &pk); free_keyserver_spec (spec); if (!rc) @@ -1815,12 +1830,14 @@ check_sig_and_print (CTX c, kbnode_t node) spec = parse_keyserver_uri (uri, 1); if (spec) { + free_public_key (pk); + pk = NULL; glo_ctrl.in_auto_key_retrieve++; res = keyserver_import_keyid (c->ctrl, sig->keyid, spec); glo_ctrl.in_auto_key_retrieve--; free_keyserver_spec (spec); if (!res) - rc = do_check_sig (c, node, NULL, &is_expkey, &is_revkey ); + rc = do_check_sig (c, node, NULL, &is_expkey, &is_revkey, &pk); } } } @@ -1844,11 +1861,13 @@ check_sig_and_print (CTX c, kbnode_t node) if (p && n == 21 && p[0] == 4) { /* v4 packet with a SHA-1 fingerprint. */ + free_public_key (pk); + pk = NULL; glo_ctrl.in_auto_key_retrieve++; res = keyserver_import_fprint (c->ctrl, p+1, n-1, opt.keyserver); glo_ctrl.in_auto_key_retrieve--; if (!res) - rc = do_check_sig (c, node, NULL, &is_expkey, &is_revkey ); + rc = do_check_sig (c, node, NULL, &is_expkey, &is_revkey, &pk); } } @@ -1862,13 +1881,15 @@ check_sig_and_print (CTX c, kbnode_t node) { int res; + free_public_key (pk); + pk = NULL; glo_ctrl.in_auto_key_retrieve++; res = keyserver_import_wkd (c->ctrl, sig->signers_uid, NULL, NULL); glo_ctrl.in_auto_key_retrieve--; /* 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, NULL, &is_expkey, &is_revkey ); + rc = do_check_sig (c, node, NULL, &is_expkey, &is_revkey, &pk); } /* If the above methods did't work, our next try is to use a @@ -1879,11 +1900,13 @@ check_sig_and_print (CTX c, kbnode_t node) { int res; + free_public_key (pk); + pk = NULL; glo_ctrl.in_auto_key_retrieve++; res = keyserver_import_keyid (c->ctrl, sig->keyid, opt.keyserver ); glo_ctrl.in_auto_key_retrieve--; if (!res) - rc = do_check_sig (c, node, NULL, &is_expkey, &is_revkey ); + rc = do_check_sig (c, node, NULL, &is_expkey, &is_revkey, &pk); } if (!rc || gpg_err_code (rc) == GPG_ERR_BAD_SIGNATURE) @@ -1892,7 +1915,7 @@ check_sig_and_print (CTX c, kbnode_t node) int count = 0; int statno; char keyid_str[50]; - PKT_public_key *pk = NULL; + PKT_public_key *mainpk = NULL; if (rc) statno = STATUS_BADSIG; @@ -1905,6 +1928,10 @@ 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 + * keyboock 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. */ keyblock = get_pubkeyblock (sig->keyid); snprintf (keyid_str, sizeof keyid_str, "%08lX%08lX [uncertain] ", @@ -1918,7 +1945,7 @@ check_sig_and_print (CTX c, kbnode_t node) if (un->pkt->pkttype==PKT_PUBLIC_KEY) { - pk=un->pkt->pkt.public_key; + mainpk = un->pkt->pkt.public_key; continue; } if (un->pkt->pkttype != PKT_USER_ID) @@ -1935,7 +1962,7 @@ check_sig_and_print (CTX c, kbnode_t node) if (un->pkt->pkt.user_id->attrib_data) continue; - log_assert (pk); + log_assert (mainpk); /* Since this is just informational, don't actually ask the user to update any trust information. (Note: we register @@ -1943,7 +1970,8 @@ check_sig_and_print (CTX c, kbnode_t node) does not print a LF we need to compute the validity before calling that function. */ if ((opt.verify_options & VERIFY_SHOW_UID_VALIDITY)) - valid = get_validity (c->ctrl, pk, un->pkt->pkt.user_id, sig, 0); + valid = get_validity (c->ctrl, mainpk, un->pkt->pkt.user_id, + sig, 0); else valid = 0; /* Not used. */ @@ -1956,13 +1984,11 @@ check_sig_and_print (CTX c, kbnode_t node) else log_printf ("\n"); - /* Get a string description of the algo for informational - output we want to print later. It is convenient to do it - here because we already have the right public key. */ - pubkey_string (pk, pkstrbuf, sizeof pkstrbuf); count++; } + log_assert (mainpk); + /* In case we did not found a valid valid textual userid above we print the first user id packet or a "[?]" instead along with the "Good|Expired|Bad signature" line. */ @@ -2019,13 +2045,13 @@ check_sig_and_print (CTX c, kbnode_t node) /* If this user id has attribute data, print that. */ if (un->pkt->pkt.user_id->attrib_data) { - dump_attribs (un->pkt->pkt.user_id, pk); + dump_attribs (un->pkt->pkt.user_id, mainpk); if (opt.verify_options&VERIFY_SHOW_PHOTOS) show_photos (c->ctrl, un->pkt->pkt.user_id->attribs, un->pkt->pkt.user_id->numattribs, - pk ,un->pkt->pkt.user_id); + mainpk ,un->pkt->pkt.user_id); } p = utf8_to_native (un->pkt->pkt.user_id->name, @@ -2046,7 +2072,7 @@ check_sig_and_print (CTX c, kbnode_t node) actually ask the user to update any trust information. */ valid = (trust_value_to_string - (get_validity (c->ctrl, pk, + (get_validity (c->ctrl, mainpk, un->pkt->pkt.user_id, sig, 0))); log_printf (" [%s]\n",valid); } @@ -2054,7 +2080,6 @@ check_sig_and_print (CTX c, kbnode_t node) log_printf ("\n"); } } - release_kbnode( keyblock ); /* For good signatures print notation data. */ if (!rc) @@ -2081,16 +2106,14 @@ check_sig_and_print (CTX c, kbnode_t node) /* For good signatures print the VALIDSIG status line. */ if (!rc && is_status_enabled ()) { - PKT_public_key *vpk = xmalloc_clear (sizeof *vpk); - - if (!get_pubkey (vpk, sig->keyid)) + if (pk) { byte array[MAX_FINGERPRINT_LEN], *p; char buf[MAX_FINGERPRINT_LEN*4+90], *bufp; size_t i, n; bufp = buf; - fingerprint_from_pk (vpk, array, &n); + fingerprint_from_pk (pk, array, &n); p = array; for(i=0; i < n ; i++, p++, bufp += 2) sprintf (bufp, "%02X", *p ); @@ -2103,29 +2126,13 @@ check_sig_and_print (CTX c, kbnode_t node) sig->version,sig->pubkey_algo,sig->digest_algo, sig->sig_class); bufp = bufp + strlen (bufp); - if (!vpk->flags.primary) - { - u32 akid[2]; - - akid[0] = vpk->main_keyid[0]; - akid[1] = vpk->main_keyid[1]; - free_public_key (vpk); - vpk = xmalloc_clear (sizeof *vpk); - if (get_pubkey (vpk, akid)) - { - /* Impossible error, we simply return a zeroed out fpr */ - n = MAX_FINGERPRINT_LEN < 20? MAX_FINGERPRINT_LEN : 20; - memset (array, 0, n); - } - else - fingerprint_from_pk( vpk, array, &n ); - } + if (!pk->flags.primary) + fingerprint_from_pk (mainpk, array, &n); p = array; for (i=0; i < n ; i++, p++, bufp += 2) sprintf(bufp, "%02X", *p ); write_status_text (STATUS_VALIDSIG, buf); } - free_public_key (vpk); } /* For good signatures compute and print the trust information. @@ -2148,12 +2155,20 @@ check_sig_and_print (CTX c, kbnode_t node) log_info (_("Signature expires %s\n"), asctimestamp(sig->expiredate)); if (opt.verbose) - log_info (_("%s signature, digest algorithm %s%s%s\n"), - sig->sig_class==0x00?_("binary"): - sig->sig_class==0x01?_("textmode"):_("unknown"), - gcry_md_algo_name (sig->digest_algo), - *pkstrbuf?_(", key algorithm "):"", - pkstrbuf); + { + char pkstrbuf[PUBKEY_STRING_SIZE]; + + if (pk) + pubkey_string (pk, pkstrbuf, sizeof pkstrbuf); + else + *pkstrbuf = 0; + + log_info (_("%s signature, digest algorithm %s%s%s\n"), + sig->sig_class==0x00?_("binary"): + sig->sig_class==0x01?_("textmode"):_("unknown"), + gcry_md_algo_name (sig->digest_algo), + *pkstrbuf?_(", key algorithm "):"", pkstrbuf); + } /* Print final warnings. */ if (!rc && !c->signed_data.used) @@ -2194,6 +2209,7 @@ check_sig_and_print (CTX c, kbnode_t node) } } + release_kbnode( keyblock ); if (rc) g10_errors_seen = 1; if (opt.batch && rc) diff --git a/g10/packet.h b/g10/packet.h index 9c9e909d8..60af2a233 100644 --- a/g10/packet.h +++ b/g10/packet.h @@ -802,13 +802,13 @@ int cmp_user_ids( PKT_user_id *a, PKT_user_id *b ); int check_signature (PKT_signature *sig, gcry_md_hd_t digest); /* Check a signature. Looks up the public key from the key db. (If - RET_PK is not NULL, it is returned in *RET_PK.) DIGEST contains a - valid hash context that already includes the signed data. This - function adds the relevant meta-data to the hash before finalizing - it and verifying the signature. */ -int check_signature2 (PKT_signature *sig, gcry_md_hd_t digest, - u32 *r_expiredate, int *r_expired, int *r_revoked, - PKT_public_key *ret_pk); + * R_PK is not NULL, it is stored at RET_PK.) DIGEST contains a + * valid hash context that already includes the signed data. This + * function adds the relevant meta-data to the hash before finalizing + * it and verifying the signature. */ +gpg_error_t check_signature2 (PKT_signature *sig, gcry_md_hd_t digest, + u32 *r_expiredate, int *r_expired, int *r_revoked, + PKT_public_key **r_pk); /*-- pubkey-enc.c --*/ diff --git a/g10/sig-check.c b/g10/sig-check.c index 334add785..4d39e0925 100644 --- a/g10/sig-check.c +++ b/g10/sig-check.c @@ -84,23 +84,29 @@ check_signature (PKT_signature *sig, gcry_md_hd_t digest) * revoked (0 otherwise). Note: PK being revoked does not cause this * function to fail. * - * If PK is not NULL, the public key is saved in *PK on success. + * If R_PK is not NULL, the public key is stored at that address if it + * was found; other wise NULL is stored. * * Returns 0 on success. An error code otherwise. */ -int +gpg_error_t check_signature2 (PKT_signature *sig, gcry_md_hd_t digest, u32 *r_expiredate, - int *r_expired, int *r_revoked, PKT_public_key *pk ) + int *r_expired, int *r_revoked, PKT_public_key **r_pk) { int rc=0; - int pk_internal; + PKT_public_key *pk; - if (pk) - pk_internal = 0; - else - { - pk_internal = 1; - pk = xmalloc_clear( sizeof *pk ); - } + if (r_expiredate) + *r_expiredate = 0; + if (r_expired) + *r_expired = 0; + if (r_revoked) + *r_revoked = 0; + if (r_pk) + *r_pk = NULL; + + pk = xtrycalloc (1, sizeof *pk); + if (!pk) + return gpg_error_from_syserror (); if ( (rc=openpgp_md_test_algo(sig->digest_algo)) ) ; /* We don't have this digest. */ @@ -114,14 +120,14 @@ check_signature2 (PKT_signature *sig, gcry_md_hd_t digest, u32 *r_expiredate, header is missing or does not match the actual sig. */ log_info(_("WARNING: signature digest conflict in message\n")); - rc = GPG_ERR_GENERAL; + rc = gpg_error (GPG_ERR_GENERAL); } else if( get_pubkey( pk, sig->keyid ) ) - rc = GPG_ERR_NO_PUBKEY; + rc = gpg_error (GPG_ERR_NO_PUBKEY); else if(!pk->flags.valid) { /* You cannot have a good sig from an invalid key. */ - rc = GPG_ERR_BAD_PUBKEY; + rc = gpg_error (GPG_ERR_BAD_PUBKEY); } else { @@ -136,7 +142,7 @@ check_signature2 (PKT_signature *sig, gcry_md_hd_t digest, u32 *r_expiredate, them as their own. The attacker couldn't actually use the subkey, but they could try and claim ownership of any signatures issued by it. */ - if(rc==0 && !pk->flags.primary && pk->flags.backsig < 2) + if (!rc && !pk->flags.primary && pk->flags.backsig < 2) { if (!pk->flags.backsig) { @@ -148,27 +154,17 @@ check_signature2 (PKT_signature *sig, gcry_md_hd_t digest, u32 *r_expiredate, error. TODO: change the default to require this after more keys have backsigs. */ if(opt.flags.require_cross_cert) - rc = GPG_ERR_GENERAL; + rc = gpg_error (GPG_ERR_GENERAL); } else if(pk->flags.backsig == 1) { log_info(_("WARNING: signing subkey %s has an invalid" " cross-certification\n"),keystr_from_pk(pk)); - rc = GPG_ERR_GENERAL; + rc = gpg_error (GPG_ERR_GENERAL); } } } - if (pk_internal || rc) - { - release_public_key_parts (pk); - if (pk_internal) - xfree (pk); - else - /* Be very sure that the caller doesn't try to use *PK. */ - memset (pk, 0, sizeof (*pk)); - } - if( !rc && sig->sig_class < 2 && is_status_enabled() ) { /* This signature id works best with DLP algorithms because * they use a random parameter for every signature. Instead of @@ -235,6 +231,14 @@ check_signature2 (PKT_signature *sig, gcry_md_hd_t digest, u32 *r_expiredate, xfree (buffer); } + if (r_pk) + *r_pk = pk; + else + { + release_public_key_parts (pk); + xfree (pk); + } + return rc; } |