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#include "includes.h"
#include "buffer.h"
#include "dbutil.h"
#include "session.h"
#include "ssh.h"
#include "runopts.h"
#include "auth.h"
static void send_msg_userauth_pubkey(sign_key *key, int type, int realsign);
/* Called when we receive a SSH_MSG_USERAUTH_FAILURE for a pubkey request.
* We use it to remove the key we tried from the list */
void cli_pubkeyfail() {
struct PubkeyList *keyitem;
TRACE(("enter cli_pubkeyfail"));
/* Find the key we failed with, and remove it */
for (keyitem = cli_opts.pubkeys; keyitem != NULL; keyitem = keyitem->next) {
if (keyitem->next == cli_ses.lastpubkey) {
keyitem->next = cli_ses.lastpubkey->next;
}
}
sign_key_free(cli_ses.lastpubkey->key); /* It won't be used again */
m_free(cli_ses.lastpubkey);
TRACE(("leave cli_pubkeyfail"));
}
void recv_msg_userauth_pk_ok() {
struct PubkeyList *keyitem;
buffer* keybuf;
char* algotype = NULL;
unsigned int algolen;
int keytype;
unsigned int remotelen;
TRACE(("enter recv_msg_userauth_pk_ok"));
algotype = buf_getstring(ses.payload, &algolen);
keytype = signkey_type_from_name(algotype, algolen);
TRACE(("recv_msg_userauth_pk_ok: type %d", keytype));
m_free(algotype);
keybuf = buf_new(MAX_PUBKEY_SIZE);
remotelen = buf_getint(ses.payload);
/* Iterate through our keys, find which one it was that matched, and
* send a real request with that key */
for (keyitem = cli_opts.pubkeys; keyitem != NULL; keyitem = keyitem->next) {
if (keyitem->type != keytype) {
/* Types differed */
TRACE(("types differed"));
continue;
}
/* Now we compare the contents of the key */
keybuf->pos = keybuf->len = 0;
buf_put_pub_key(keybuf, keyitem->key, keytype);
buf_setpos(keybuf, 0);
buf_incrpos(keybuf, 4); /* first int is the length of the remainder (ie
remotelen) which has already been taken from
the remote buffer */
if (keybuf->len-4 != remotelen) {
TRACE(("lengths differed: localh %d remote %d", keybuf->len, remotelen));
/* Lengths differed */
continue;
}
if (memcmp(buf_getptr(keybuf, remotelen),
buf_getptr(ses.payload, remotelen), remotelen) != 0) {
/* Data didn't match this key */
TRACE(("data differed"));
continue;
}
/* Success */
break;
}
if (keyitem != NULL) {
TRACE(("matching key"));
/* XXX TODO: if it's an encrypted key, here we ask for their
* password */
send_msg_userauth_pubkey(keyitem->key, keytype, 1);
} else {
TRACE(("That was whacky. We got told that a key was valid, but it didn't match our list. Sounds like dodgy code on Dropbear's part"));
}
TRACE(("leave recv_msg_userauth_pk_ok"));
}
/* TODO: make it take an agent reference to use as well */
static void send_msg_userauth_pubkey(sign_key *key, int type, int realsign) {
const char *algoname = NULL;
int algolen;
buffer* sigbuf = NULL;
TRACE(("enter send_msg_userauth_pubkey"));
CHECKCLEARTOWRITE();
buf_putbyte(ses.writepayload, SSH_MSG_USERAUTH_REQUEST);
buf_putstring(ses.writepayload, cli_opts.username,
strlen(cli_opts.username));
buf_putstring(ses.writepayload, SSH_SERVICE_CONNECTION,
SSH_SERVICE_CONNECTION_LEN);
buf_putstring(ses.writepayload, AUTH_METHOD_PUBKEY,
AUTH_METHOD_PUBKEY_LEN);
buf_putbyte(ses.writepayload, realsign);
algoname = signkey_name_from_type(type, &algolen);
buf_putstring(ses.writepayload, algoname, algolen);
buf_put_pub_key(ses.writepayload, key, type);
if (realsign) {
TRACE(("realsign"));
/* We put the signature as well - this contains string(session id), then
* the contents of the write payload to this point */
sigbuf = buf_new(4 + SHA1_HASH_SIZE + ses.writepayload->len);
buf_putstring(sigbuf, ses.session_id, SHA1_HASH_SIZE);
buf_putbytes(sigbuf, ses.writepayload->data, ses.writepayload->len);
buf_put_sign(ses.writepayload, key, type, sigbuf->data, sigbuf->len);
buf_free(sigbuf); /* Nothing confidential in the buffer */
}
encrypt_packet();
TRACE(("leave send_msg_userauth_pubkey"));
}
int cli_auth_pubkey() {
TRACE(("enter cli_auth_pubkey"));
if (cli_opts.pubkeys != NULL) {
/* Send a trial request */
send_msg_userauth_pubkey(cli_opts.pubkeys->key,
cli_opts.pubkeys->type, 0);
TRACE(("leave cli_auth_pubkey-success"));
return 1;
} else {
TRACE(("leave cli_auth_pubkey-failure"));
return 0;
}
}
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