/*
* pageant.c: cross-platform code to implement Pageant.
*/
#include <stddef.h>
#include <stdlib.h>
#include <assert.h>
#include "putty.h"
#include "mpint.h"
#include "ssh.h"
#include "sshcr.h"
#include "pageant.h"
/*
* We need this to link with the RSA code, because rsa_ssh1_encrypt()
* pads its data with random bytes. Since we only use rsa_ssh1_decrypt()
* and the signing functions, which are deterministic, this should
* never be called.
*
* If it _is_ called, there is a _serious_ problem, because it
* won't generate true random numbers. So we must scream, panic,
* and exit immediately if that should happen.
*/
void random_read(void *buf, size_t size)
{
modalfatalbox("Internal error: attempt to use random numbers in Pageant");
}
static bool pageant_local = false;
/*
* rsakeys stores SSH-1 RSA keys. ssh2keys stores all SSH-2 keys.
*/
static tree234 *rsakeys, *ssh2keys;
/*
* Key comparison function for the 2-3-4 tree of RSA keys.
*/
static int cmpkeys_rsa(void *av, void *bv)
{
RSAKey *a = (RSAKey *) av;
RSAKey *b = (RSAKey *) bv;
return ((int)mp_cmp_hs(a->modulus, b->modulus) -
(int)mp_cmp_hs(b->modulus, a->modulus));
}
/*
* Key comparison function for looking up a blob in the 2-3-4 tree
* of SSH-2 keys.
*/
static int cmpkeys_ssh2_asymm(void *av, void *bv)
{
ptrlen *ablob = (ptrlen *) av;
ssh2_userkey *b = (ssh2_userkey *) bv;
strbuf *bblob;
int i, c;
/*
* Compare purely by public blob.
*/
bblob = strbuf_new();
ssh_key_public_blob(b->key, BinarySink_UPCAST(bblob));
c = 0;
for (i = 0; i < ablob->len && i < bblob->len; i++) {
unsigned char abyte = ((unsigned char *)ablob->ptr)[i];
if (abyte < bblob->u[i]) {
c = -1;
break;
} else if (abyte > bblob->u[i]) {
c = +1;
break;
}
}
if (c == 0 && i < ablob->len)
c = +1; /* a is longer */
if (c == 0 && i < bblob->len)
c = -1; /* a is longer */
strbuf_free(bblob);
return c;
}
/*
* Main key comparison function for the 2-3-4 tree of SSH-2 keys.
*/
static int cmpkeys_ssh2(void *av, void *bv)
{
ssh2_userkey *a = (ssh2_userkey *) av;
strbuf *ablob;
ptrlen apl;
int toret;
ablob = strbuf_new();
ssh_key_public_blob(a->key, BinarySink_UPCAST(ablob));
apl.ptr = ablob->u;
apl.len = ablob->len;
toret = cmpkeys_ssh2_asymm(&apl, bv);
strbuf_free(ablob);
return toret;
}
void pageant_make_keylist1(BinarySink *bs)
{
int i;
RSAKey *key;
put_uint32(bs, count234(rsakeys));
for (i = 0; NULL != (key = index234(rsakeys, i)); i++) {
rsa_ssh1_public_blob(bs, key, RSA_SSH1_EXPONENT_FIRST);
put_stringz(bs, key->comment);
}
}
void pageant_make_keylist2(BinarySink *bs)
{
int i;
ssh2_userkey *key;
put_uint32(bs, count234(ssh2keys));
for (i = 0; NULL != (key = index234(ssh2keys, i)); i++) {
strbuf *blob = strbuf_new();
ssh_key_public_blob(key->key, BinarySink_UPCAST(blob));
put_stringsb(bs, blob);
put_stringz(bs, key->comment);
}
}
static void plog(void *logctx, pageant_logfn_t logfn, const char *fmt, ...)
#ifdef __GNUC__
__attribute__ ((format (printf, 3, 4)))
#endif
;
static void plog(void *logctx, pageant_logfn_t logfn, const char *fmt, ...)
{
/*
* This is the wrapper that takes a variadic argument list and
* turns it into the va_list that the log function really expects.
* It's safe to call this with logfn==NULL, because we
* double-check that below; but if you're going to do lots of work
* before getting here (such as looping, or hashing things) then
* you should probably check logfn manually before doing that.
*/
if (logfn) {
va_list ap;
va_start(ap, fmt);
logfn(logctx, fmt, ap);
va_end(ap);
}
}
void pageant_handle_msg(BinarySink *bs,
const void *msgdata, int msglen,
void *logctx, pageant_logfn_t logfn)
{
BinarySource msg[1];
int type;
BinarySource_BARE_INIT(msg, msgdata, msglen);
type = get_byte(msg);
if (get_err(msg)) {
pageant_failure_msg(bs, "message contained no type code",
logctx, logfn);
return;
}
switch (type) {
case SSH1_AGENTC_REQUEST_RSA_IDENTITIES:
/*
* Reply with SSH1_AGENT_RSA_IDENTITIES_ANSWER.
*/
{
plog(logctx, logfn, "request: SSH1_AGENTC_REQUEST_RSA_IDENTITIES");
put_byte(bs, SSH1_AGENT_RSA_IDENTITIES_ANSWER);
pageant_make_keylist1(bs);
plog(logctx, logfn, "reply: SSH1_AGENT_RSA_IDENTITIES_ANSWER");
if (logfn) { /* skip this loop if not logging */
int i;
RSAKey *rkey;
for (i = 0; NULL != (rkey = pageant_nth_ssh1_key(i)); i++) {
char *fingerprint = rsa_ssh1_fingerprint(rkey);
plog(logctx, logfn, "returned key: %s", fingerprint);
sfree(fingerprint);
}
}
}
break;
case SSH2_AGENTC_REQUEST_IDENTITIES:
/*
* Reply with SSH2_AGENT_IDENTITIES_ANSWER.
*/
{
plog(logctx, logfn, "request: SSH2_AGENTC_REQUEST_IDENTITIES");
put_byte(bs, SSH2_AGENT_IDENTITIES_ANSWER);
pageant_make_keylist2(bs);
plog(logctx, logfn, "reply: SSH2_AGENT_IDENTITIES_ANSWER");
if (logfn) { /* skip this loop if not logging */
int i;
ssh2_userkey *skey;
for (i = 0; NULL != (skey = pageant_nth_ssh2_key(i)); i++) {
char *fingerprint = ssh2_fingerprint(skey->key);
plog(logctx, logfn, "returned key: %s %s",
fingerprint, skey->comment);
sfree(fingerprint);
}
}
}
break;
case SSH1_AGENTC_RSA_CHALLENGE:
/*
* Reply with either SSH1_AGENT_RSA_RESPONSE or
* SSH_AGENT_FAILURE, depending on whether we have that key
* or not.
*/
{
RSAKey reqkey, *key;
mp_int *challenge, *response;
ptrlen session_id;
unsigned response_type;
unsigned char response_md5[16];
int i;
plog(logctx, logfn, "request: SSH1_AGENTC_RSA_CHALLENGE");
response = NULL;
memset(&reqkey, 0, sizeof(reqkey));
get_rsa_ssh1_pub(msg, &reqkey, RSA_SSH1_EXPONENT_FIRST);
challenge = get_mp_ssh1(msg);
session_id = get_data(msg, 16);
response_type = get_uint32(msg);
if (get_err(msg)) {
pageant_failure_msg(bs, "unable to decode request",
logctx, logfn);
goto challenge1_cleanup;
}
if (response_type != 1) {
pageant_failure_msg(
bs, "response type other than 1 not supported",
logctx, logfn);
goto challenge1_cleanup;
}
if (logfn) {
char *fingerprint;
reqkey.comment = NULL;
fingerprint = rsa_ssh1_fingerprint(&reqkey);
plog(logctx, logfn, "requested key: %s", fingerprint);
sfree(fingerprint);
}
if ((key = find234(rsakeys, &reqkey, NULL)) == NULL) {
pageant_failure_msg(bs, "key not found", logctx, logfn);
goto challenge1_cleanup;
}
response = rsa_ssh1_decrypt(challenge, key);
{
ssh_hash *h = ssh_hash_new(&ssh_md5);
for (i = 0; i < 32; i++)
put_byte(h, mp_get_byte(response, 31 - i));
put_datapl(h, session_id);
ssh_hash_final(h, response_md5);
}
put_byte(bs, SSH1_AGENT_RSA_RESPONSE);
put_data(bs, response_md5, 16);
plog(logctx, logfn, "reply: SSH1_AGENT_RSA_RESPONSE");
challenge1_cleanup:
if (response)
mp_free(response);
mp_free(challenge);
freersakey(&reqkey);
}
break;
case SSH2_AGENTC_SIGN_REQUEST:
/*
* Reply with either SSH2_AGENT_SIGN_RESPONSE or
* SSH_AGENT_FAILURE, depending on whether we have that key
* or not.
*/
{
ssh2_userkey *key;
ptrlen keyblob, sigdata;
strbuf *signature;
uint32_t flags, supported_flags;
plog(logctx, logfn, "request: SSH2_AGENTC_SIGN_REQUEST");
keyblob = get_string(msg);
sigdata = get_string(msg);
if (get_err(msg)) {
pageant_failure_msg(bs, "unable to decode request",
logctx, logfn);
return;
}
/*
* Later versions of the agent protocol added a flags word
* on the end of the sign request. That hasn't always been
* there, so we don't complain if we don't find it.
*
* get_uint32 will default to returning zero if no data is
* available.
*/
bool have_flags = false;
flags = get_uint32(msg);
if (!get_err(msg))
have_flags = true;
if (logfn) {
char *fingerprint = ssh2_fingerprint_blob(keyblob);
plog(logctx, logfn, "requested key: %s", fingerprint);
sfree(fingerprint);
}
key = find234(ssh2keys, &keyblob, cmpkeys_ssh2_asymm);
if (!key) {
pageant_failure_msg(bs, "key not found", logctx, logfn);
return;
}
if (have_flags)
plog(logctx, logfn, "signature flags = 0x%08"PRIx32, flags);
else
plog(logctx, logfn, "no signature flags");
supported_flags = ssh_key_alg(key->key)->supported_flags;
if (flags & ~supported_flags) {
/*
* We MUST reject any message containing flags we
* don't understand.
*/
char *msg = dupprintf(
"unsupported flag bits 0x%08"PRIx32,
flags & ~supported_flags);
pageant_failure_msg(bs, msg, logctx, logfn);
sfree(msg);
return;
}
char *invalid = ssh_key_invalid(key->key, flags);
if (invalid) {
char *msg = dupprintf("key invalid: %s", invalid);
pageant_failure_msg(bs, msg, logctx, logfn);
sfree(msg);
sfree(invalid);
return;
}
signature = strbuf_new();
ssh_key_sign(key->key, sigdata, flags,
BinarySink_UPCAST(signature));
put_byte(bs, SSH2_AGENT_SIGN_RESPONSE);
put_stringsb(bs, signature);
plog(logctx, logfn, "reply: SSH2_AGENT_SIGN_RESPONSE");
}
break;
case SSH1_AGENTC_ADD_RSA_IDENTITY:
/*
* Add to the list and return SSH_AGENT_SUCCESS, or
* SSH_AGENT_FAILURE if the key was malformed.
*/
{
RSAKey *key;
plog(logctx, logfn, "request: SSH1_AGENTC_ADD_RSA_IDENTITY");
key = snew(RSAKey);
memset(key, 0, sizeof(RSAKey));
get_rsa_ssh1_pub(msg, key, RSA_SSH1_MODULUS_FIRST);
get_rsa_ssh1_priv(msg, key);
/* SSH-1 names p and q the other way round, i.e. we have
* the inverse of p mod q and not of q mod p. We swap the
* names, because our internal RSA wants iqmp. */
key->iqmp = get_mp_ssh1(msg);
key->q = get_mp_ssh1(msg);
key->p = get_mp_ssh1(msg);
key->comment = mkstr(get_string(msg));
if (get_err(msg)) {
pageant_failure_msg(bs, "unable to decode request",
logctx, logfn);
goto add1_cleanup;
}
if (!rsa_verify(key)) {
pageant_failure_msg(bs, "key is invalid", logctx, logfn);
goto add1_cleanup;
}
if (logfn) {
char *fingerprint = rsa_ssh1_fingerprint(key);
plog(logctx, logfn, "submitted key: %s", fingerprint);
sfree(fingerprint);
}
if (add234(rsakeys, key) == key) {
keylist_update();
put_byte(bs, SSH_AGENT_SUCCESS);
plog(logctx, logfn, "reply: SSH_AGENT_SUCCESS");
key = NULL; /* don't free it in cleanup */
} else {
pageant_failure_msg(bs, "key already present",
logctx, logfn);
}
add1_cleanup:
if (key) {
freersakey(key);
sfree(key);
}
}
break;
case SSH2_AGENTC_ADD_IDENTITY:
/*
* Add to the list and return SSH_AGENT_SUCCESS, or
* SSH_AGENT_FAILURE if the key was malformed.
*/
{
ssh2_userkey *key = NULL;
ptrlen algpl;
const ssh_keyalg *alg;
plog(logctx, logfn, "request: SSH2_AGENTC_ADD_IDENTITY");
algpl = get_string(msg);
key = snew(ssh2_userkey);
key->key = NULL;
key->comment = NULL;
alg = find_pubkey_alg_len(algpl);
if (!alg) {
pageant_failure_msg(bs, "algorithm unknown", logctx, logfn);
goto add2_cleanup;
}
key->key = ssh_key_new_priv_openssh(alg, msg);
if (!key->key) {
pageant_failure_msg(bs, "key setup failed", logctx, logfn);
goto add2_cleanup;
}
key->comment = mkstr(get_string(msg));
if (get_err(msg)) {
pageant_failure_msg(bs, "unable to decode request",
logctx, logfn);
goto add2_cleanup;
}
if (logfn) {
char *fingerprint = ssh2_fingerprint(key->key);
plog(logctx, logfn, "submitted key: %s %s",
fingerprint, key->comment);
sfree(fingerprint);
}
if (add234(ssh2keys, key) == key) {
keylist_update();
put_byte(bs, SSH_AGENT_SUCCESS);
plog(logctx, logfn, "reply: SSH_AGENT_SUCCESS");
key = NULL; /* don't clean it up */
} else {
pageant_failure_msg(bs, "key already present",
logctx, logfn);
}
add2_cleanup:
if (key) {
if (key->key)
ssh_key_free(key->key);
if (key->comment)
sfree(key->comment);
sfree(key);
}
}
break;
case SSH1_AGENTC_REMOVE_RSA_IDENTITY:
/*
* Remove from the list and return SSH_AGENT_SUCCESS, or
* perhaps SSH_AGENT_FAILURE if it wasn't in the list to
* start with.
*/
{
RSAKey reqkey, *key;
plog(logctx, logfn, "request: SSH1_AGENTC_REMOVE_RSA_IDENTITY");
memset(&reqkey, 0, sizeof(reqkey));
get_rsa_ssh1_pub(msg, &reqkey, RSA_SSH1_EXPONENT_FIRST);
if (get_err(msg)) {
pageant_failure_msg(bs, "unable to decode request",
logctx, logfn);
freersakey(&reqkey);
return;
}
if (logfn) {
char *fingerprint;
reqkey.comment = NULL;
fingerprint = rsa_ssh1_fingerprint(&reqkey);
plog(logctx, logfn, "unwanted key: %s", fingerprint);
sfree(fingerprint);
}
key = find234(rsakeys, &reqkey, NULL);
freersakey(&reqkey);
if (key) {
plog(logctx, logfn, "found with comment: %s", key->comment);
del234(rsakeys, key);
keylist_update();
freersakey(key);
sfree(key);
put_byte(bs, SSH_AGENT_SUCCESS);
plog(logctx, logfn, "reply: SSH_AGENT_SUCCESS");
} else {
pageant_failure_msg(bs, "key not found", logctx, logfn);
}
}
break;
case SSH2_AGENTC_REMOVE_IDENTITY:
/*
* Remove from the list and return SSH_AGENT_SUCCESS, or
* perhaps SSH_AGENT_FAILURE if it wasn't in the list to
* start with.
*/
{
ssh2_userkey *key;
ptrlen blob;
plog(logctx, logfn, "request: SSH2_AGENTC_REMOVE_IDENTITY");
blob = get_string(msg);
if (get_err(msg)) {
pageant_failure_msg(bs, "unable to decode request",
logctx, logfn);
return;
}
if (logfn) {
char *fingerprint = ssh2_fingerprint_blob(blob);
plog(logctx, logfn, "unwanted key: %s", fingerprint);
sfree(fingerprint);
}
key = find234(ssh2keys, &blob, cmpkeys_ssh2_asymm);
if (!key) {
pageant_failure_msg(bs, "key not found", logctx, logfn);
return;
}
plog(logctx, logfn, "found with comment: %s", key->comment);
del234(ssh2keys, key);
keylist_update();
ssh_key_free(key->key);
sfree(key->comment);
sfree(key);
put_byte(bs, SSH_AGENT_SUCCESS);
plog(logctx, logfn, "reply: SSH_AGENT_SUCCESS");
}
break;
case SSH1_AGENTC_REMOVE_ALL_RSA_IDENTITIES:
/*
* Remove all SSH-1 keys. Always returns success.
*/
{
RSAKey *rkey;
plog(logctx, logfn, "request:"
" SSH1_AGENTC_REMOVE_ALL_RSA_IDENTITIES");
while ((rkey = index234(rsakeys, 0)) != NULL) {
del234(rsakeys, rkey);
freersakey(rkey);
sfree(rkey);
}
keylist_update();
put_byte(bs, SSH_AGENT_SUCCESS);
plog(logctx, logfn, "reply: SSH_AGENT_SUCCESS");
}
break;
case SSH2_AGENTC_REMOVE_ALL_IDENTITIES:
/*
* Remove all SSH-2 keys. Always returns success.
*/
{
ssh2_userkey *skey;
plog(logctx, logfn, "request: SSH2_AGENTC_REMOVE_ALL_IDENTITIES");
while ((skey = index234(ssh2keys, 0)) != NULL) {
del234(ssh2keys, skey);
ssh_key_free(skey->key);
sfree(skey->comment);
sfree(skey);
}
keylist_update();
put_byte(bs, SSH_AGENT_SUCCESS);
plog(logctx, logfn, "reply: SSH_AGENT_SUCCESS");
}
break;
default:
plog(logctx, logfn, "request: unknown message type %d", type);
pageant_failure_msg(bs, "unrecognised message", logctx, logfn);
break;
}
}
void pageant_failure_msg(BinarySink *bs,
const char *log_reason,
void *logctx, pageant_logfn_t logfn)
{
put_byte(bs, SSH_AGENT_FAILURE);
plog(logctx, logfn, "reply: SSH_AGENT_FAILURE (%s)", log_reason);
}
void pageant_init(void)
{
pageant_local = true;
rsakeys = newtree234(cmpkeys_rsa);
ssh2keys = newtree234(cmpkeys_ssh2);
}
RSAKey *pageant_nth_ssh1_key(int i)
{
return index234(rsakeys, i);
}
ssh2_userkey *pageant_nth_ssh2_key(int i)
{
return index234(ssh2keys, i);
}
int pageant_count_ssh1_keys(void)
{
return count234(rsakeys);
}
int pageant_count_ssh2_keys(void)
{
return count234(ssh2keys);
}
bool pageant_add_ssh1_key(RSAKey *rkey)
{
return add234(rsakeys, rkey) == rkey;
}
bool pageant_add_ssh2_key(ssh2_userkey *skey)
{
return add234(ssh2keys, skey) == skey;
}
bool pageant_delete_ssh1_key(RSAKey *rkey)
{
RSAKey *deleted = del234(rsakeys, rkey);
if (!deleted)
return false;
assert(deleted == rkey);
return true;
}
bool pageant_delete_ssh2_key(ssh2_userkey *skey)
{
ssh2_userkey *deleted = del234(ssh2keys, skey);
if (!deleted)
return false;
assert(deleted == skey);
return true;
}
/* ----------------------------------------------------------------------
* The agent plug.
*/
/*
* An extra coroutine macro, specific to this code which is consuming
* 'const char *data'.
*/
#define crGetChar(c) do \
{ \
while (len == 0) { \
*crLine =__LINE__; return; case __LINE__:; \
} \
len--; \
(c) = (unsigned char)*data++; \
} while (0)
struct pageant_conn_state {
Socket *connsock;
void *logctx;
pageant_logfn_t logfn;
unsigned char lenbuf[4], pktbuf[AGENT_MAX_MSGLEN];
unsigned len, got;
bool real_packet;
int crLine; /* for coroutine in pageant_conn_receive */
Plug plug;
};
static void pageant_conn_closing(Plug *plug, const char *error_msg,
int error_code, bool calling_back)
{
struct pageant_conn_state *pc = container_of(
plug, struct pageant_conn_state, plug);
if (error_msg)
plog(pc->logctx, pc->logfn, "%p: error: %s", pc, error_msg);
else
plog(pc->logctx, pc->logfn, "%p: connection closed", pc);
sk_close(pc->connsock);
sfree(pc);
}
static void pageant_conn_sent(Plug *plug, size_t bufsize)
{
/* struct pageant_conn_state *pc = container_of(
plug, struct pageant_conn_state, plug); */
/*
* We do nothing here, because we expect that there won't be a
* need to throttle and unthrottle the connection to an agent -
* clients will typically not send many requests, and will wait
* until they receive each reply before sending a new request.
*/
}
static void pageant_conn_log(void *logctx, const char *fmt, va_list ap)
{
/* Wrapper on pc->logfn that prefixes the connection identifier */
struct pageant_conn_state *pc = (struct pageant_conn_state *)logctx;
char *formatted = dupvprintf(fmt, ap);
plog(pc->logctx, pc->logfn, "%p: %s", pc, formatted);
sfree(formatted);
}
static void pageant_conn_receive(
Plug *plug, int urgent, const char *data, size_t len)
{
struct pageant_conn_state *pc = container_of(
plug, struct pageant_conn_state, plug);
char c;
crBegin(pc->crLine);
while (len > 0) {
pc->got = 0;
while (pc->got < 4) {
crGetChar(c);
pc->lenbuf[pc->got++] = c;
}
pc->len = GET_32BIT_MSB_FIRST(pc->lenbuf);
pc->got = 0;
pc->real_packet = (pc->len < AGENT_MAX_MSGLEN-4);
while (pc->got < pc->len) {
crGetChar(c);
if (pc->real_packet)
pc->pktbuf[pc->got] = c;
pc->got++;
}
{
strbuf *reply = strbuf_new();
put_uint32(reply, 0); /* length field to fill in later */
if (pc->real_packet) {
pageant_handle_msg(BinarySink_UPCAST(reply), pc->pktbuf, pc->len, pc,
pc->logfn ? pageant_conn_log : NULL);
} else {
plog(pc->logctx, pc->logfn, "%p: overlong message (%u)",
pc, pc->len);
pageant_failure_msg(BinarySink_UPCAST(reply), "message too long", pc,
pc->logfn ? pageant_conn_log : NULL);
}
PUT_32BIT_MSB_FIRST(reply->s, reply->len - 4);
sk_write(pc->connsock, reply->s, reply->len);
strbuf_free(reply);
}
}
crFinishV;
}
struct pageant_listen_state {
Socket *listensock;
void *logctx;
pageant_logfn_t logfn;
Plug plug;
};
static void pageant_listen_closing(Plug *plug, const char *error_msg,
int error_code, bool calling_back)
{
struct pageant_listen_state *pl = container_of(
plug, struct pageant_listen_state, plug);
if (error_msg)
plog(pl->logctx, pl->logfn, "listening socket: error: %s", error_msg);
sk_close(pl->listensock);
pl->listensock = NULL;
}
static const PlugVtable pageant_connection_plugvt = {
NULL, /* no log function, because that's for outgoing connections */
pageant_conn_closing,
pageant_conn_receive,
pageant_conn_sent,
NULL /* no accepting function, because we've already done it */
};
static int pageant_listen_accepting(Plug *plug,
accept_fn_t constructor, accept_ctx_t ctx)
{
struct pageant_listen_state *pl = container_of(
plug, struct pageant_listen_state, plug);
struct pageant_conn_state *pc;
const char *err;
SocketPeerInfo *peerinfo;
pc = snew(struct pageant_conn_state);
pc->plug.vt = &pageant_connection_plugvt;
pc->logfn = pl->logfn;
pc->logctx = pl->logctx;
pc->crLine = 0;
pc->connsock = constructor(ctx, &pc->plug);
if ((err = sk_socket_error(pc->connsock)) != NULL) {
sk_close(pc->connsock);
sfree(pc);
return 1;
}
sk_set_frozen(pc->connsock, 0);
peerinfo = sk_peer_info(pc->connsock);
if (peerinfo && peerinfo->log_text) {
plog(pl->logctx, pl->logfn, "%p: new connection from %s",
pc, peerinfo->log_text);
} else {
plog(pl->logctx, pl->logfn, "%p: new connection", pc);
}
sk_free_peer_info(peerinfo);
return 0;
}
static const PlugVtable pageant_listener_plugvt = {
NULL, /* no log function, because that's for outgoing connections */
pageant_listen_closing,
NULL, /* no receive function on a listening socket */
NULL, /* no sent function on a listening socket */
pageant_listen_accepting
};
struct pageant_listen_state *pageant_listener_new(Plug **plug)
{
struct pageant_listen_state *pl = snew(struct pageant_listen_state);
pl->plug.vt = &pageant_listener_plugvt;
pl->logctx = NULL;
pl->logfn = NULL;
pl->listensock = NULL;
*plug = &pl->plug;
return pl;
}
void pageant_listener_got_socket(struct pageant_listen_state *pl, Socket *sock)
{
pl->listensock = sock;
}
void pageant_listener_set_logfn(struct pageant_listen_state *pl,
void *logctx, pageant_logfn_t logfn)
{
pl->logctx = logctx;
pl->logfn = logfn;
}
void pageant_listener_free(struct pageant_listen_state *pl)
{
if (pl->listensock)
sk_close(pl->listensock);
sfree(pl);
}
/* ----------------------------------------------------------------------
* Code to perform agent operations either as a client, or within the
* same process as the running agent.
*/
static tree234 *passphrases = NULL;
/*
* After processing a list of filenames, we want to forget the
* passphrases.
*/
void pageant_forget_passphrases(void)
{
if (!passphrases) /* in case we never set it up at all */
return;
while (count234(passphrases) > 0) {
char *pp = index234(passphrases, 0);
smemclr(pp, strlen(pp));
delpos234(passphrases, 0);
free(pp);
}
}
void *pageant_get_keylist1(int *length)
{
void *ret;
if (!pageant_local) {
strbuf *request;
unsigned char *response;
void *vresponse;
int resplen;
request = strbuf_new_for_agent_query();
put_byte(request, SSH1_AGENTC_REQUEST_RSA_IDENTITIES);
agent_query_synchronous(request, &vresponse, &resplen);
strbuf_free(request);
response = vresponse;
if (resplen < 5 || response[4] != SSH1_AGENT_RSA_IDENTITIES_ANSWER) {
sfree(response);
return NULL;
}
ret = snewn(resplen-5, unsigned char);
memcpy(ret, response+5, resplen-5);
sfree(response);
if (length)
*length = resplen-5;
} else {
strbuf *buf = strbuf_new();
pageant_make_keylist1(BinarySink_UPCAST(buf));
*length = buf->len;
ret = strbuf_to_str(buf);
}
return ret;
}
void *pageant_get_keylist2(int *length)
{
void *ret;
if (!pageant_local) {
strbuf *request;
unsigned char *response;
void *vresponse;
int resplen;
request = strbuf_new_for_agent_query();
put_byte(request, SSH2_AGENTC_REQUEST_IDENTITIES);
agent_query_synchronous(request, &vresponse, &resplen);
strbuf_free(request);
response = vresponse;
if (resplen < 5 || response[4] != SSH2_AGENT_IDENTITIES_ANSWER) {
sfree(response);
return NULL;
}
ret = snewn(resplen-5, unsigned char);
memcpy(ret, response+5, resplen-5);
sfree(response);
if (length)
*length = resplen-5;
} else {
strbuf *buf = strbuf_new();
pageant_make_keylist2(BinarySink_UPCAST(buf));
*length = buf->len;
ret = strbuf_to_str(buf);
}
return ret;
}
int pageant_add_keyfile(Filename *filename, const char *passphrase,
char **retstr)
{
RSAKey *rkey = NULL;
ssh2_userkey *skey = NULL;
bool needs_pass;
int ret;
int attempts;
char *comment;
const char *this_passphrase;
const char *error = NULL;
int type;
if (!passphrases) {
passphrases = newtree234(NULL);
}
*retstr = NULL;
type = key_type(filename);
if (type != SSH_KEYTYPE_SSH1 && type != SSH_KEYTYPE_SSH2) {
*retstr = dupprintf("Couldn't load this key (%s)",
key_type_to_str(type));
return PAGEANT_ACTION_FAILURE;
}
/*
* See if the key is already loaded (in the primary Pageant,
* which may or may not be us).
*/
{
strbuf *blob = strbuf_new();
unsigned char *keylist, *p;
int i, nkeys, keylistlen;
if (type == SSH_KEYTYPE_SSH1) {
if (!rsa_ssh1_loadpub(filename, BinarySink_UPCAST(blob), NULL, &error)) {
*retstr = dupprintf("Couldn't load private key (%s)", error);
strbuf_free(blob);
return PAGEANT_ACTION_FAILURE;
}
keylist = pageant_get_keylist1(&keylistlen);
} else {
/* For our purposes we want the blob prefixed with its
* length, so add a placeholder here to fill in
* afterwards */
put_uint32(blob, 0);
if (!ssh2_userkey_loadpub(filename, NULL, BinarySink_UPCAST(blob),
NULL, &error)) {
*retstr = dupprintf("Couldn't load private key (%s)", error);
strbuf_free(blob);
return PAGEANT_ACTION_FAILURE;
}
PUT_32BIT_MSB_FIRST(blob->s, blob->len - 4);
keylist = pageant_get_keylist2(&keylistlen);
}
if (keylist) {
if (keylistlen < 4) {
*retstr = dupstr("Received broken key list from agent");
sfree(keylist);
strbuf_free(blob);
return PAGEANT_ACTION_FAILURE;
}
nkeys = toint(GET_32BIT_MSB_FIRST(keylist));
if (nkeys < 0) {
*retstr = dupstr("Received broken key list from agent");
sfree(keylist);
strbuf_free(blob);
return PAGEANT_ACTION_FAILURE;
}
p = keylist + 4;
keylistlen -= 4;
for (i = 0; i < nkeys; i++) {
if (!memcmp(blob->s, p, blob->len)) {
/* Key is already present; we can now leave. */
sfree(keylist);
strbuf_free(blob);
return PAGEANT_ACTION_OK;
}
/* Now skip over public blob */
if (type == SSH_KEYTYPE_SSH1) {
int n = rsa_ssh1_public_blob_len(
make_ptrlen(p, keylistlen));
if (n < 0) {
*retstr = dupstr("Received broken key list from agent");
sfree(keylist);
strbuf_free(blob);
return PAGEANT_ACTION_FAILURE;
}
p += n;
keylistlen -= n;
} else {
int n;
if (keylistlen < 4) {
*retstr = dupstr("Received broken key list from agent");
sfree(keylist);
strbuf_free(blob);
return PAGEANT_ACTION_FAILURE;
}
n = GET_32BIT_MSB_FIRST(p);
p += 4;
keylistlen -= 4;
if (n < 0 || n > keylistlen) {
*retstr = dupstr("Received broken key list from agent");
sfree(keylist);
strbuf_free(blob);
return PAGEANT_ACTION_FAILURE;
}
p += n;
keylistlen -= n;
}
/* Now skip over comment field */
{
int n;
if (keylistlen < 4) {
*retstr = dupstr("Received broken key list from agent");
sfree(keylist);
strbuf_free(blob);
return PAGEANT_ACTION_FAILURE;
}
n = GET_32BIT_MSB_FIRST(p);
p += 4;
keylistlen -= 4;
if (n < 0 || n > keylistlen) {
*retstr = dupstr("Received broken key list from agent");
sfree(keylist);
strbuf_free(blob);
return PAGEANT_ACTION_FAILURE;
}
p += n;
keylistlen -= n;
}
}
sfree(keylist);
}
strbuf_free(blob);
}
error = NULL;
if (type == SSH_KEYTYPE_SSH1)
needs_pass = rsa_ssh1_encrypted(filename, &comment);
else
needs_pass = ssh2_userkey_encrypted(filename, &comment);
attempts = 0;
if (type == SSH_KEYTYPE_SSH1)
rkey = snew(RSAKey);
/*
* Loop round repeatedly trying to load the key, until we either
* succeed, fail for some serious reason, or run out of
* passphrases to try.
*/
while (1) {
if (needs_pass) {
/*
* If we've been given a passphrase on input, try using
* it. Otherwise, try one from our tree234 of previously
* useful passphrases.
*/
if (passphrase) {
this_passphrase = (attempts == 0 ? passphrase : NULL);
} else {
this_passphrase = (const char *)index234(passphrases, attempts);
}
if (!this_passphrase) {
/*
* Run out of passphrases to try.
*/
*retstr = comment;
sfree(rkey);
return PAGEANT_ACTION_NEED_PP;
}
} else
this_passphrase = "";
if (type == SSH_KEYTYPE_SSH1)
ret = rsa_ssh1_loadkey(filename, rkey, this_passphrase, &error);
else {
skey = ssh2_load_userkey(filename, this_passphrase, &error);
if (skey == SSH2_WRONG_PASSPHRASE)
ret = -1;
else if (!skey)
ret = 0;
else
ret = 1;
}
if (ret == 0) {
/*
* Failed to load the key file, for some reason other than
* a bad passphrase.
*/
*retstr = dupstr(error);
sfree(rkey);
return PAGEANT_ACTION_FAILURE;
} else if (ret == 1) {
/*
* Successfully loaded the key file.
*/
break;
} else {
/*
* Passphrase wasn't right; go round again.
*/
attempts++;
}
}
/*
* If we get here, we've successfully loaded the key into
* rkey/skey, but not yet added it to the agent.
*/
/*
* If the key was successfully decrypted, save the passphrase for
* use with other keys we try to load.
*/
{
char *pp_copy = dupstr(this_passphrase);
if (addpos234(passphrases, pp_copy, 0) != pp_copy) {
/* No need; it was already there. */
smemclr(pp_copy, strlen(pp_copy));
sfree(pp_copy);
}
}
if (comment)
sfree(comment);
if (type == SSH_KEYTYPE_SSH1) {
if (!pageant_local) {
strbuf *request;
unsigned char *response;
void *vresponse;
int resplen;
request = strbuf_new_for_agent_query();
put_byte(request, SSH1_AGENTC_ADD_RSA_IDENTITY);
put_uint32(request, mp_get_nbits(rkey->modulus));
put_mp_ssh1(request, rkey->modulus);
put_mp_ssh1(request, rkey->exponent);
put_mp_ssh1(request, rkey->private_exponent);
put_mp_ssh1(request, rkey->iqmp);
put_mp_ssh1(request, rkey->q);
put_mp_ssh1(request, rkey->p);
put_stringz(request, rkey->comment);
agent_query_synchronous(request, &vresponse, &resplen);
strbuf_free(request);
response = vresponse;
if (resplen < 5 || response[4] != SSH_AGENT_SUCCESS) {
*retstr = dupstr("The already running Pageant "
"refused to add the key.");
freersakey(rkey);
sfree(rkey);
sfree(response);
return PAGEANT_ACTION_FAILURE;
}
freersakey(rkey);
sfree(rkey);
sfree(response);
} else {
if (!pageant_add_ssh1_key(rkey)) {
freersakey(rkey);
sfree(rkey); /* already present, don't waste RAM */
}
}
} else {
if (!pageant_local) {
strbuf *request;
unsigned char *response;
void *vresponse;
int resplen;
request = strbuf_new_for_agent_query();
put_byte(request, SSH2_AGENTC_ADD_IDENTITY);
put_stringz(request, ssh_key_ssh_id(skey->key));
ssh_key_openssh_blob(skey->key, BinarySink_UPCAST(request));
put_stringz(request, skey->comment);
agent_query_synchronous(request, &vresponse, &resplen);
strbuf_free(request);
response = vresponse;
if (resplen < 5 || response[4] != SSH_AGENT_SUCCESS) {
*retstr = dupstr("The already running Pageant "
"refused to add the key.");
sfree(response);
return PAGEANT_ACTION_FAILURE;
}
sfree(response);
} else {
if (!pageant_add_ssh2_key(skey)) {
ssh_key_free(skey->key);
sfree(skey); /* already present, don't waste RAM */
}
}
}
return PAGEANT_ACTION_OK;
}
int pageant_enum_keys(pageant_key_enum_fn_t callback, void *callback_ctx,
char **retstr)
{
unsigned char *keylist;
int i, nkeys, keylistlen;
ptrlen comment;
struct pageant_pubkey cbkey;
BinarySource src[1];
keylist = pageant_get_keylist1(&keylistlen);
if (!keylist) {
*retstr = dupstr("Did not receive an SSH-1 key list from agent");
return PAGEANT_ACTION_FAILURE;
}
BinarySource_BARE_INIT(src, keylist, keylistlen);
nkeys = toint(get_uint32(src));
for (i = 0; i < nkeys; i++) {
RSAKey rkey;
char *fingerprint;
/* public blob and fingerprint */
memset(&rkey, 0, sizeof(rkey));
get_rsa_ssh1_pub(src, &rkey, RSA_SSH1_EXPONENT_FIRST);
comment = get_string(src);
if (get_err(src)) {
*retstr = dupstr("Received broken SSH-1 key list from agent");
freersakey(&rkey);
sfree(keylist);
return PAGEANT_ACTION_FAILURE;
}
fingerprint = rsa_ssh1_fingerprint(&rkey);
cbkey.blob = strbuf_new();
rsa_ssh1_public_blob(BinarySink_UPCAST(cbkey.blob), &rkey,
RSA_SSH1_EXPONENT_FIRST);
cbkey.comment = mkstr(comment);
cbkey.ssh_version = 1;
callback(callback_ctx, fingerprint, cbkey.comment, &cbkey);
strbuf_free(cbkey.blob);
freersakey(&rkey);
sfree(cbkey.comment);
sfree(fingerprint);
}
sfree(keylist);
if (get_err(src) || get_avail(src) != 0) {
*retstr = dupstr("Received broken SSH-1 key list from agent");
return PAGEANT_ACTION_FAILURE;
}
keylist = pageant_get_keylist2(&keylistlen);
if (!keylist) {
*retstr = dupstr("Did not receive an SSH-2 key list from agent");
return PAGEANT_ACTION_FAILURE;
}
BinarySource_BARE_INIT(src, keylist, keylistlen);
nkeys = toint(get_uint32(src));
for (i = 0; i < nkeys; i++) {
ptrlen pubblob;
char *fingerprint;
pubblob = get_string(src);
comment = get_string(src);
if (get_err(src)) {
*retstr = dupstr("Received broken SSH-2 key list from agent");
sfree(keylist);
return PAGEANT_ACTION_FAILURE;
}
fingerprint = ssh2_fingerprint_blob(pubblob);
cbkey.blob = strbuf_new();
put_datapl(cbkey.blob, pubblob);
cbkey.ssh_version = 2;
cbkey.comment = mkstr(comment);
callback(callback_ctx, fingerprint, cbkey.comment, &cbkey);
sfree(fingerprint);
sfree(cbkey.comment);
}
sfree(keylist);
if (get_err(src) || get_avail(src) != 0) {
*retstr = dupstr("Received broken SSH-2 key list from agent");
return PAGEANT_ACTION_FAILURE;
}
return PAGEANT_ACTION_OK;
}
int pageant_delete_key(struct pageant_pubkey *key, char **retstr)
{
strbuf *request;
unsigned char *response;
int resplen, ret;
void *vresponse;
request = strbuf_new_for_agent_query();
if (key->ssh_version == 1) {
put_byte(request, SSH1_AGENTC_REMOVE_RSA_IDENTITY);
put_data(request, key->blob->s, key->blob->len);
} else {
put_byte(request, SSH2_AGENTC_REMOVE_IDENTITY);
put_string(request, key->blob->s, key->blob->len);
}
agent_query_synchronous(request, &vresponse, &resplen);
strbuf_free(request);
response = vresponse;
if (resplen < 5 || response[4] != SSH_AGENT_SUCCESS) {
*retstr = dupstr("Agent failed to delete key");
ret = PAGEANT_ACTION_FAILURE;
} else {
*retstr = NULL;
ret = PAGEANT_ACTION_OK;
}
sfree(response);
return ret;
}
int pageant_delete_all_keys(char **retstr)
{
strbuf *request;
unsigned char *response;
int resplen;
bool success;
void *vresponse;
request = strbuf_new_for_agent_query();
put_byte(request, SSH2_AGENTC_REMOVE_ALL_IDENTITIES);
agent_query_synchronous(request, &vresponse, &resplen);
strbuf_free(request);
response = vresponse;
success = (resplen >= 4 && response[4] == SSH_AGENT_SUCCESS);
sfree(response);
if (!success) {
*retstr = dupstr("Agent failed to delete SSH-2 keys");
return PAGEANT_ACTION_FAILURE;
}
request = strbuf_new_for_agent_query();
put_byte(request, SSH1_AGENTC_REMOVE_ALL_RSA_IDENTITIES);
agent_query_synchronous(request, &vresponse, &resplen);
strbuf_free(request);
response = vresponse;
success = (resplen >= 4 && response[4] == SSH_AGENT_SUCCESS);
sfree(response);
if (!success) {
*retstr = dupstr("Agent failed to delete SSH-1 keys");
return PAGEANT_ACTION_FAILURE;
}
*retstr = NULL;
return PAGEANT_ACTION_OK;
}
struct pageant_pubkey *pageant_pubkey_copy(struct pageant_pubkey *key)
{
struct pageant_pubkey *ret = snew(struct pageant_pubkey);
ret->blob = strbuf_new();
put_data(ret->blob, key->blob->s, key->blob->len);
ret->comment = key->comment ? dupstr(key->comment) : NULL;
ret->ssh_version = key->ssh_version;
return ret;
}
void pageant_pubkey_free(struct pageant_pubkey *key)
{
sfree(key->comment);
strbuf_free(key->blob);
sfree(key);
}