* keyserver-internal.h, keyserver.c (keyserver_import_pka): Use the

same API as the other auto-key-locate fetchers.

* getkey.c (get_pubkey_byname): Use the fingerprint of the key that we
actually fetched.  This helps prevent problems where the key that we
fetched doesn't have the same name that we used to fetch it.  In the
case of CERT and PKA, this is an actual security requirement as the
URL might point to a key put in by an attacker.  By forcing the use of
the fingerprint, we won't use the attacker's key here.
This commit is contained in:
David Shaw 2006-03-14 03:16:21 +00:00
parent b478ce7a79
commit 9f524c4a04
4 changed files with 61 additions and 31 deletions

View File

@ -1,5 +1,16 @@
2006-03-13 David Shaw <dshaw@jabberwocky.com>
* keyserver-internal.h, keyserver.c (keyserver_import_pka): Use
the same API as the other auto-key-locate fetchers.
* getkey.c (get_pubkey_byname): Use the fingerprint of the key
that we actually fetched. This helps prevent problems where the
key that we fetched doesn't have the same name that we used to
fetch it. In the case of CERT and PKA, this is an actual security
requirement as the URL might point to a key put in by an attacker.
By forcing the use of the fingerprint, we won't use the attacker's
key here.
* keyserver-internal.h, keyserver.c (keyserver_spawn,
keyserver_work, keyserver_import_cert, keyserver_import_name,
keyserver_import_ldap): Pass fingerprint info through.

View File

@ -922,11 +922,14 @@ get_pubkey_byname (PKT_public_key *pk,
for(akl=opt.auto_key_locate;akl;akl=akl->next)
{
unsigned char *fpr;
size_t fpr_len;
switch(akl->type)
{
case AKL_CERT:
glo_ctrl.in_auto_key_retrieve++;
res=keyserver_import_cert(name,NULL,NULL);
res=keyserver_import_cert(name,&fpr,&fpr_len);
glo_ctrl.in_auto_key_retrieve--;
if(res==0)
@ -935,35 +938,17 @@ get_pubkey_byname (PKT_public_key *pk,
break;
case AKL_PKA:
{
unsigned char fpr[MAX_FINGERPRINT_LEN];
glo_ctrl.in_auto_key_retrieve++;
res=keyserver_import_pka(name,&fpr,&fpr_len);
glo_ctrl.in_auto_key_retrieve++;
res=keyserver_import_pka(name,fpr);
glo_ctrl.in_auto_key_retrieve--;
if(res==0)
{
int i;
char fpr_string[MAX_FINGERPRINT_LEN*2+1];
log_info(_("Automatically retrieved `%s' via %s\n"),
name,"PKA");
free_strlist(namelist);
namelist=NULL;
for(i=0;i<MAX_FINGERPRINT_LEN;i++)
sprintf(fpr_string+2*i,"%02X",fpr[i]);
add_to_strlist( &namelist, fpr_string );
}
}
if(res==0)
log_info(_("Automatically retrieved `%s' via %s\n"),
name,"PKA");
break;
case AKL_LDAP:
glo_ctrl.in_auto_key_retrieve++;
res=keyserver_import_ldap(name,NULL,NULL);
res=keyserver_import_ldap(name,&fpr,&fpr_len);
glo_ctrl.in_auto_key_retrieve--;
if(res==0)
@ -979,7 +964,7 @@ get_pubkey_byname (PKT_public_key *pk,
if(opt.keyserver)
{
glo_ctrl.in_auto_key_retrieve++;
res=keyserver_import_name(name,NULL,NULL,opt.keyserver);
res=keyserver_import_name(name,&fpr,&fpr_len,opt.keyserver);
glo_ctrl.in_auto_key_retrieve--;
if(res==0)
@ -994,7 +979,7 @@ get_pubkey_byname (PKT_public_key *pk,
keyserver=keyserver_match(akl->spec);
glo_ctrl.in_auto_key_retrieve++;
res=keyserver_import_name(name,NULL,NULL,keyserver);
res=keyserver_import_name(name,&fpr,&fpr_len,keyserver);
glo_ctrl.in_auto_key_retrieve--;
if(res==0)
@ -1004,6 +989,34 @@ get_pubkey_byname (PKT_public_key *pk,
break;
}
/* Use the fingerprint of the key that we actually fetched.
This helps prevent problems where the key that we fetched
doesn't have the same name that we used to fetch it. In
the case of CERT and PKA, this is an actual security
requirement as the URL might point to a key put in by an
attacker. By forcing the use of the fingerprint, we
won't use the attacker's key here. */
if(res==0 && fpr)
{
int i;
char fpr_string[MAX_FINGERPRINT_LEN*2+1];
assert(fpr_len<=MAX_FINGERPRINT_LEN);
free_strlist(namelist);
namelist=NULL;
for(i=0;i<fpr_len;i++)
sprintf(fpr_string+2*i,"%02X",fpr[i]);
if(opt.verbose)
log_info("auto-key-locate found fingerprint %s\n",fpr_string);
add_to_strlist( &namelist, fpr_string );
xfree(fpr);
}
rc = key_byname( NULL, namelist, pk, NULL, 0,
include_unusable, ret_keyblock, ret_kdbhd);
if(rc!=G10ERR_NO_PUBKEY)

View File

@ -45,7 +45,7 @@ int keyserver_search(STRLIST tokens);
int keyserver_fetch(STRLIST urilist);
int keyserver_import_cert(const char *name,
unsigned char **fpr,size_t *fpr_len);
int keyserver_import_pka(const char *name,unsigned char *fpr);
int keyserver_import_pka(const char *name,unsigned char **fpr,size_t *fpr_len);
int keyserver_import_name(const char *name,unsigned char **fpr,size_t *fpr_len,
struct keyserver_spec *keyserver);
int keyserver_import_ldap(const char *name,

View File

@ -2036,24 +2036,30 @@ keyserver_import_cert(const char *name,unsigned char **fpr,size_t *fpr_len)
/* Import key pointed to by a PKA record. Return the requested
fingerprint in fpr. */
int
keyserver_import_pka(const char *name,unsigned char *fpr)
keyserver_import_pka(const char *name,unsigned char **fpr,size_t *fpr_len)
{
char *uri;
int rc=-1;
uri = get_pka_info (name, fpr);
*fpr=xmalloc(20);
*fpr_len=20;
uri = get_pka_info (name, *fpr);
if (uri)
{
struct keyserver_spec *spec;
spec = parse_keyserver_uri (uri, 1, NULL, 0);
if (spec)
{
rc=keyserver_import_fprint (fpr, 20, spec);
rc=keyserver_import_fprint (*fpr, 20, spec);
free_keyserver_spec (spec);
}
xfree (uri);
}
if(rc!=0)
xfree(*fpr);
return rc;
}