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client.c
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client.c
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/*
* PgBouncer - Lightweight connection pooler for PostgreSQL.
*
* Copyright (c) 2007-2009 Marko Kreen, Skype Technologies OÜ
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
/*
* Client connection handling
*/
#include "bouncer.h"
#include "pam.h"
#include "scram.h"
#include <usual/pgutil.h>
static const char *hdr2hex(const struct MBuf *data, char *buf, unsigned buflen)
{
const uint8_t *bin = data->data + data->read_pos;
unsigned int dlen;
dlen = mbuf_avail_for_read(data);
return bin2hex(bin, dlen, buf, buflen);
}
/*
* Get authentication database for the current client. The order of preference is:
* client->db->auth_dbname: per client authentication database
* cf_auth_dbname: global authentication database
* client->db: client database
*
* NOTE: if the authentication database is not found or it is disabled, client
* will be disconnected.
*/
PgDatabase *prepare_auth_database(PgSocket *client)
{
PgDatabase *auth_db = NULL;
const char *auth_dbname = client->db->auth_dbname ? client->db->auth_dbname : cf_auth_dbname;
if (!auth_dbname) {
auth_db = client->db;
} else {
auth_db = find_database(auth_dbname);
}
if (!auth_db) {
slog_error(client, "authentication database \"%s\" is not configured.", auth_dbname);
disconnect_client(client, true, "bouncer config error");
return NULL;
}
if (auth_db->db_disabled) {
disconnect_client(
client,
true,
"authentication database \"%s\" is disabled",
auth_dbname);
return NULL;
}
if (auth_db->admin) {
slog_error(client, "cannot use the reserved \"%s\" database as an auth_dbname", auth_db->dbname);
disconnect_client(client, true, "bouncer config error");
return NULL;
}
return auth_db;
}
static bool check_client_passwd(PgSocket *client, const char *passwd)
{
PgUser *user = client->login_user;
int auth_type = client->client_auth_type;
if (user->mock_auth)
return false;
/* disallow empty passwords */
if (!*user->passwd)
return false;
switch (auth_type) {
case AUTH_PLAIN:
switch (get_password_type(user->passwd)) {
case PASSWORD_TYPE_PLAINTEXT:
return strcmp(user->passwd, passwd) == 0;
case PASSWORD_TYPE_MD5: {
char md5[MD5_PASSWD_LEN + 1];
pg_md5_encrypt(passwd, user->name, strlen(user->name), md5);
return strcmp(user->passwd, md5) == 0;
}
case PASSWORD_TYPE_SCRAM_SHA_256:
return scram_verify_plain_password(client, user->name, passwd, user->passwd);
default:
return false;
}
case AUTH_MD5: {
char *stored_passwd;
char md5[MD5_PASSWD_LEN + 1];
if (strlen(passwd) != MD5_PASSWD_LEN)
return false;
/*
* The client sends
* 'md5'+md5(md5(password+username)+salt). The stored
* password is either 'md5'+md5(password+username) or
* plain text. If the latter, we compute the inner
* md5() call first.
*/
if (get_password_type(user->passwd) == PASSWORD_TYPE_PLAINTEXT) {
pg_md5_encrypt(user->passwd, user->name, strlen(user->name), md5);
stored_passwd = md5;
} else {
stored_passwd = user->passwd;
}
pg_md5_encrypt(stored_passwd + 3, (char *)client->tmp_login_salt, 4, md5);
return strcmp(md5, passwd) == 0;
}
}
return false;
}
static bool send_client_authreq(PgSocket *client)
{
int res;
int auth_type = client->client_auth_type;
if (auth_type == AUTH_MD5) {
uint8_t saltlen = 4;
get_random_bytes((void*)client->tmp_login_salt, saltlen);
SEND_generic(res, client, 'R', "ib", AUTH_MD5, client->tmp_login_salt, saltlen);
} else if (auth_type == AUTH_PLAIN || auth_type == AUTH_PAM) {
SEND_generic(res, client, 'R', "i", AUTH_PLAIN);
} else if (auth_type == AUTH_SCRAM_SHA_256) {
SEND_generic(res, client, 'R', "iss", AUTH_SASL, "SCRAM-SHA-256", "");
} else {
return false;
}
if (!res) {
slog_noise(client, "No authentication response received");
disconnect_client(client, false, "failed to send auth req");
} else {
slog_noise(client, "Auth request sent successfully");
}
return res;
}
static void start_auth_query(PgSocket *client, const char *username)
{
int res;
PktBuf *buf;
/* have to fetch user info from db */
PgDatabase *auth_db = prepare_auth_database(client);
if (!auth_db)
return;
client->pool = get_pool(auth_db, client->db->auth_user);
if (!find_server(client)) {
client->wait_for_user_conn = true;
return;
}
slog_noise(client, "doing auth_conn query");
client->wait_for_user_conn = false;
client->wait_for_user = true;
if (!sbuf_pause(&client->sbuf)) {
release_server(client->link);
disconnect_client(client, true, "pause failed");
return;
}
client->link->ready = false;
res = 0;
buf = pktbuf_dynamic(512);
if (buf) {
pktbuf_write_ExtQuery(buf, cf_auth_query, 1, username);
res = pktbuf_send_immediate(buf, client->link);
pktbuf_free(buf);
/*
* Should do instead:
* res = pktbuf_send_queued(buf, client->link);
* but that needs better integration with SBuf.
*/
}
if (!res)
disconnect_server(client->link, false, "unable to send auth_query");
client->expect_rfq_count++;
}
static bool login_via_cert(PgSocket *client)
{
struct tls *tls = client->sbuf.tls;
if (!tls) {
slog_error(client, "TLS connection required");
goto fail;
}
if (!tls_peer_cert_provided(client->sbuf.tls)) {
slog_error(client, "TLS client certificate required");
goto fail;
}
if (client->login_user->mock_auth)
goto fail;
log_debug("TLS cert login: %s", tls_peer_cert_subject(client->sbuf.tls));
if (!tls_peer_cert_contains_name(client->sbuf.tls, client->login_user->name)) {
slog_error(client, "TLS certificate name mismatch");
goto fail;
}
/* login successful */
return finish_client_login(client);
fail:
disconnect_client(client, true, "certificate authentication failed");
return false;
}
static bool login_as_unix_peer(PgSocket *client)
{
if (!pga_is_unix(&client->remote_addr))
goto fail;
if (client->login_user->mock_auth)
goto fail;
if (!check_unix_peer_name(sbuf_socket(&client->sbuf), client->login_user->name))
goto fail;
return finish_client_login(client);
fail:
disconnect_client(client, true, "unix socket login rejected");
return false;
}
static bool finish_set_pool(PgSocket *client, bool takeover)
{
bool ok = false;
int auth;
if (!client->login_user->mock_auth && !client->db->fake) {
PgUser *pool_user;
if (client->db->forced_user)
pool_user = client->db->forced_user;
else
pool_user = client->login_user;
client->pool = get_pool(client->db, pool_user);
if (!client->pool) {
disconnect_client(client, true, "no memory for pool");
return false;
}
}
if (cf_log_connections) {
if (client->sbuf.tls) {
char infobuf[96] = "";
tls_get_connection_info(client->sbuf.tls, infobuf, sizeof infobuf);
slog_info(client, "login attempt: db=%s user=%s tls=%s",
client->db->name, client->login_user->name, infobuf);
} else {
slog_info(client, "login attempt: db=%s user=%s tls=no",
client->db->name, client->login_user->name);
}
}
if (takeover)
return true;
if (client->pool && client->pool->db->admin) {
if (!admin_post_login(client))
return false;
}
if (client->own_user)
return finish_client_login(client);
auth = cf_auth_type;
if (auth == AUTH_HBA) {
auth = hba_eval(parsed_hba, &client->remote_addr, !!client->sbuf.tls,
client->db->name, client->login_user->name);
}
if (auth == AUTH_MD5)
{
if (get_password_type(client->login_user->passwd) == PASSWORD_TYPE_SCRAM_SHA_256)
auth = AUTH_SCRAM_SHA_256;
}
/* remember method */
client->client_auth_type = auth;
switch (auth) {
case AUTH_ANY:
ok = finish_client_login(client);
break;
case AUTH_TRUST:
if (client->login_user->mock_auth)
disconnect_client(client, true, "\"trust\" authentication failed");
else
ok = finish_client_login(client);
break;
case AUTH_PLAIN:
case AUTH_MD5:
case AUTH_PAM:
case AUTH_SCRAM_SHA_256:
ok = send_client_authreq(client);
break;
case AUTH_CERT:
ok = login_via_cert(client);
break;
case AUTH_PEER:
ok = login_as_unix_peer(client);
break;
default:
disconnect_client(client, true, "login rejected");
ok = false;
}
return ok;
}
bool set_pool(PgSocket *client, const char *dbname, const char *username, const char *password, bool takeover)
{
Assert((password && takeover) || (!password && !takeover));
/* find database */
client->db = find_database(dbname);
if (!client->db) {
client->db = register_auto_database(dbname);
if (client->db)
slog_info(client, "registered new auto-database: db=%s", dbname);
}
if (!client->db) {
client->db = calloc(1, sizeof(*client->db));
client->db->fake = true;
strlcpy(client->db->name, dbname, sizeof(client->db->name));
}
if (client->db->admin) {
if (admin_pre_login(client, username))
return finish_set_pool(client, takeover);
}
/* avoid dealing with invalid data below, and give an
* appropriate error message */
if (strlen(username) >= MAX_USERNAME) {
disconnect_client(client, true, "username too long");
if (cf_log_connections)
slog_info(client, "login failed: db=%s user=%s", dbname, username);
return false;
}
if (password && strlen(password) >= MAX_PASSWORD) {
disconnect_client(client, true, "password too long");
if (cf_log_connections)
slog_info(client, "login failed: db=%s user=%s", dbname, username);
return false;
}
/* find user */
if (cf_auth_type == AUTH_ANY) {
/* ignore requested user */
if (client->db->forced_user == NULL) {
slog_error(client, "auth_type=any requires forced user");
disconnect_client(client, true, "bouncer config error");
return false;
}
client->login_user = client->db->forced_user;
} else if (cf_auth_type == AUTH_PAM) {
if (client->db->auth_user) {
slog_error(client, "PAM can't be used together with database authentication");
disconnect_client(client, true, "bouncer config error");
return false;
}
/* Password will be set after successful authentication when not in takeover mode */
client->login_user = add_pam_user(username, password);
if (!client->login_user) {
slog_error(client, "set_pool(): failed to allocate new PAM user");
disconnect_client(client, true, "bouncer resources exhaustion");
return false;
}
} else {
client->login_user = find_user(username);
if (!client->login_user) {
/*
* If the login user specified by the client
* does not exist, check if an auth_user is
* set and if so send off an auth_query. If
* no auth_user is set for the db, see if the
* global auth_user is set and use that.
*/
if (!client->db->auth_user && cf_auth_user) {
client->db->auth_user = find_user(cf_auth_user);
if (!client->db->auth_user)
client->db->auth_user = add_user(cf_auth_user, "");
}
if (client->db->auth_user) {
if (client->db->fake)
slog_debug(client, "not running auth_query because database is fake");
else {
if (takeover) {
client->login_user = add_db_user(client->db, username, password);
return finish_set_pool(client, takeover);
}
start_auth_query(client, username);
return false;
}
}
slog_info(client, "no such user: %s", username);
client->login_user = calloc(1, sizeof(*client->login_user));
client->login_user->mock_auth = true;
safe_strcpy(client->login_user->name, username, sizeof(client->login_user->name));
}
}
return finish_set_pool(client, takeover);
}
bool handle_auth_query_response(PgSocket *client, PktHdr *pkt) {
uint16_t columns;
uint32_t length;
const char *username, *password;
PgUser user;
PgSocket *server = client->link;
switch(pkt->type) {
case 'T': /* RowDescription */
if (!mbuf_get_uint16be(&pkt->data, &columns)) {
disconnect_server(server, false, "bad packet");
return false;
}
if (columns != 2u) {
disconnect_server(server, false, "expected 2 columns from auth_query, not %hu", columns);
return false;
}
break;
case 'D': /* DataRow */
memset(&user, 0, sizeof(user));
if (!mbuf_get_uint16be(&pkt->data, &columns)) {
disconnect_server(server, false, "bad packet");
return false;
}
if (columns != 2u) {
disconnect_server(server, false, "expected 2 columns from auth_query, not %hu", columns);
return false;
}
if (!mbuf_get_uint32be(&pkt->data, &length)) {
disconnect_server(server, false, "bad packet");
return false;
}
if (length == (uint32_t)-1) {
disconnect_server(server, false, "auth_query response contained null user name");
return false;
}
if (!mbuf_get_chars(&pkt->data, length, &username)) {
disconnect_server(server, false, "bad packet");
return false;
}
if (sizeof(user.name) - 1 < length)
length = sizeof(user.name) - 1;
memcpy(user.name, username, length);
if (!mbuf_get_uint32be(&pkt->data, &length)) {
disconnect_server(server, false, "bad packet");
return false;
}
if (length == (uint32_t)-1) {
/*
* NULL - set an md5 password with an impossible value,
* so that nothing will ever match
*/
password = "md5";
length = 3;
} else {
if (!mbuf_get_chars(&pkt->data, length, &password)) {
disconnect_server(server, false, "bad packet");
return false;
}
}
if (sizeof(user.passwd) - 1 < length)
length = sizeof(user.passwd) - 1;
memcpy(user.passwd, password, length);
client->login_user = add_db_user(client->db, user.name, user.passwd);
if (!client->login_user) {
disconnect_server(server, false, "unable to allocate new user for auth");
return false;
}
break;
case 'N': /* NoticeResponse */
break;
case 'C': /* CommandComplete */
break;
case '1': /* ParseComplete */
break;
case '2': /* BindComplete */
break;
case 'S': /* ParameterStatus */
break;
case 'Z': /* ReadyForQuery */
sbuf_prepare_skip(&client->link->sbuf, pkt->len);
if (!client->login_user) {
if (cf_log_connections)
slog_info(client, "login failed: db=%s", client->db->name);
/*
* TODO: Currently no mock authentication when
* using auth_query/auth_user; we just abort
* with a revealing message to the client.
* The main problem is that at this point we
* don't know the original user name anymore
* to do that. As a workaround, the
* auth_query could be written in a way that
* it returns a fake user and password if the
* requested user doesn't exist.
*/
disconnect_client(client, true, "no such user");
} else {
slog_noise(client, "auth query complete");
client->link->resetting = true;
sbuf_continue(&client->sbuf);
}
/*
* either sbuf_continue or disconnect_client could disconnect the server
* way down in their bowels of other callbacks. so check that, and
* return appropriately (similar to reuse_on_release)
*/
if (server->state == SV_FREE || server->state == SV_JUSTFREE)
return false;
return true;
case 'E': /* ErrorResponse */
disconnect_server(server, false, "error response from auth_query");
return false;
default:
disconnect_server(server, false, "unexpected response from auth_query");
return false;
}
sbuf_prepare_skip(&server->sbuf, pkt->len);
return true;
}
static inline const char *skip_ws(const char *position)
{
while (*position && isspace(*position))
position++;
return position;
}
_MUSTCHECK
static bool get_escaped_string(struct MBuf *buf, const char **position_ptr)
{
const char *position = *position_ptr;
const char *unwritten_start = position;
while (*position)
{
if (*position == '\\') {
if (!mbuf_write(buf, unwritten_start, position-unwritten_start))
return false;
position++;
unwritten_start = position;
if (!*position)
break;
} else if (isspace(*position)) {
break;
}
position++;
}
if (!mbuf_write(buf, unwritten_start, position-unwritten_start))
return false;
if (!mbuf_write_byte(buf, '\0'))
return false;
*position_ptr = position;
return true;
}
static bool set_startup_options(PgSocket *client, const char *options)
{
char arg_buf[400];
struct MBuf arg;
const char *position = options;
mbuf_init_fixed_writer(&arg, arg_buf, sizeof(arg_buf));
slog_error(client, "received options: %s", options);
while (*position) {
const char *key_string, *value_string;
char *equals;
mbuf_rewind_writer(&arg);
position = skip_ws(position);
if (strncmp("-c", position, 2) != 0)
goto fail;
position += 2;
position = skip_ws(position);
if (!get_escaped_string(&arg, &position)) {
disconnect_client(client, true, "unsupported options startup parameter: parameter too long");
return false;
}
equals = strchr((char *) arg.data, '=');
if (!equals)
goto fail;
*equals = '\0';
key_string = (const char *) arg.data;
value_string = (const char *) equals + 1;
if (varcache_set(&client->vars, key_string, value_string)) {
slog_debug(client, "got var from options: %s=%s", key_string, value_string);
} else if (strlist_contains(cf_ignore_startup_params, key_string)) {
slog_debug(client, "ignoring startup parameter from options: %s=%s", key_string, value_string);
} else {
slog_warning(client, "unsupported startup parameter in options: %s=%s", key_string, value_string);
disconnect_client(client, true, "unsupported startup parameter: %s", key_string);
}
}
return true;
fail:
disconnect_client(client, true, "unsupported options startup parameter: only '-c config=val' is allowed");
return false;
}
static void set_appname(PgSocket *client, const char *app_name)
{
char buf[400], abuf[300];
const char *details;
if (cf_application_name_add_host) {
/* give app a name */
if (!app_name)
app_name = "app";
/* add details */
details = pga_details(&client->remote_addr, abuf, sizeof(abuf));
snprintf(buf, sizeof(buf), "%s - %s", app_name, details);
app_name = buf;
}
if (app_name) {
slog_debug(client, "using application_name: %s", app_name);
varcache_set(&client->vars, "application_name", app_name);
}
}
static bool decide_startup_pool(PgSocket *client, PktHdr *pkt)
{
const char *username = NULL, *dbname = NULL;
const char *key, *val;
bool ok;
bool appname_found = false;
while (1) {
ok = mbuf_get_string(&pkt->data, &key);
if (!ok || *key == 0)
break;
ok = mbuf_get_string(&pkt->data, &val);
if (!ok)
break;
if (strcmp(key, "database") == 0) {
slog_debug(client, "got var: %s=%s", key, val);
dbname = val;
} else if (strcmp(key, "user") == 0) {
slog_debug(client, "got var: %s=%s", key, val);
username = val;
} else if (strcmp(key, "options") == 0) {
if (!set_startup_options(client, val))
return false;
} else if (strcmp(key, "application_name") == 0) {
set_appname(client, val);
appname_found = true;
} else if (varcache_set(&client->vars, key, val)) {
slog_debug(client, "got var: %s=%s", key, val);
} else if (strlist_contains(cf_ignore_startup_params, key)) {
slog_debug(client, "ignoring startup parameter: %s=%s", key, val);
} else {
slog_warning(client, "unsupported startup parameter: %s=%s", key, val);
disconnect_client(client, true, "unsupported startup parameter: %s", key);
return false;
}
}
if (!username || !username[0]) {
disconnect_client(client, true, "no username supplied");
return false;
}
/* if missing dbname, default to username */
if (!dbname || !dbname[0])
dbname = username;
/* create application_name if requested */
if (!appname_found)
set_appname(client, NULL);
/* check if limit allows, don't limit admin db
nb: new incoming conn will be attached to PgSocket, thus
get_active_client_count() counts it */
if (get_active_client_count() > cf_max_client_conn) {
if (strcmp(dbname, "pgbouncer") != 0) {
disconnect_client(client, true, "no more connections allowed (max_client_conn)");
return false;
}
}
/* find pool */
return set_pool(client, dbname, username, NULL, false);
}
static bool scram_client_first(PgSocket *client, uint32_t datalen, const uint8_t *data)
{
char *ibuf;
char *input;
int res;
PgUser *user = client->login_user;
ibuf = malloc(datalen + 1);
if (ibuf == NULL)
return false;
memcpy(ibuf, data, datalen);
ibuf[datalen] = '\0';
input = ibuf;
slog_debug(client, "SCRAM client-first-message = \"%s\"", input);
if (!read_client_first_message(client, input,
&client->scram_state.cbind_flag,
&client->scram_state.client_first_message_bare,
&client->scram_state.client_nonce))
goto failed;
if (!user->mock_auth) {
slog_debug(client, "stored secret = \"%s\"", user->passwd);
switch (get_password_type(user->passwd)) {
case PASSWORD_TYPE_MD5:
slog_error(client, "SCRAM authentication failed: user has MD5 secret");
goto failed;
case PASSWORD_TYPE_PLAINTEXT:
case PASSWORD_TYPE_SCRAM_SHA_256:
break;
}
}
if (!build_server_first_message(&client->scram_state, user->name, user->mock_auth ? NULL : user->passwd))
goto failed;
slog_debug(client, "SCRAM server-first-message = \"%s\"", client->scram_state.server_first_message);
SEND_generic(res, client, 'R', "ib",
AUTH_SASL_CONT,
client->scram_state.server_first_message,
strlen(client->scram_state.server_first_message));
free(ibuf);
return res;
failed:
free(ibuf);
return false;
}
static bool scram_client_final(PgSocket *client, uint32_t datalen, const uint8_t *data)
{
char *ibuf;
char *input;
const char *client_final_nonce = NULL;
char *proof = NULL;
char *server_final_message;
int res;
ibuf = malloc(datalen + 1);
if (ibuf == NULL)
return false;
memcpy(ibuf, data, datalen);
ibuf[datalen] = '\0';
input = ibuf;
slog_debug(client, "SCRAM client-final-message = \"%s\"", input);
if (!read_client_final_message(client, data, input,
&client_final_nonce,
&proof))
goto failed;
slog_debug(client, "SCRAM client-final-message-without-proof = \"%s\"",
client->scram_state.client_final_message_without_proof);
if (!verify_final_nonce(&client->scram_state, client_final_nonce)) {
slog_error(client, "invalid SCRAM response (nonce does not match)");
goto failed;
}
if (!verify_client_proof(&client->scram_state, proof)
|| !client->login_user) {
slog_error(client, "password authentication failed");
goto failed;
}
server_final_message = build_server_final_message(&client->scram_state);
if (!server_final_message)
goto failed;
slog_debug(client, "SCRAM server-final-message = \"%s\"", server_final_message);
SEND_generic(res, client, 'R', "ib",
AUTH_SASL_FIN,
server_final_message,
strlen(server_final_message));
free(server_final_message);
free(proof);
free(ibuf);
return res;
failed:
free(proof);
free(ibuf);
return false;
}
/* decide on packets of client in login phase */
static bool handle_client_startup(PgSocket *client, PktHdr *pkt)
{
const char *passwd;
const uint8_t *key;
bool ok;
bool is_unix = pga_is_unix(&client->remote_addr);
SBuf *sbuf = &client->sbuf;
/* don't tolerate partial packets */
if (incomplete_pkt(pkt)) {
disconnect_client(client, true, "client sent partial pkt in startup phase");
return false;
}
if (client->wait_for_welcome || client->wait_for_auth) {
if (finish_client_login(client)) {
/* the packet was already parsed */
sbuf_prepare_skip(sbuf, pkt->len);
return true;
} else {
return false;
}
}
switch (pkt->type) {
case PKT_SSLREQ:
slog_noise(client, "C: req SSL");
if (client->sbuf.tls) {
disconnect_client(client, false, "SSL req inside SSL");
return false;
}
if (client_accept_sslmode != SSLMODE_DISABLED && !is_unix) {
slog_noise(client, "P: SSL ack");
if (!sbuf_answer(&client->sbuf, "S", 1)) {
disconnect_client(client, false, "failed to ack SSL");
return false;
}
if (!sbuf_tls_accept(&client->sbuf)) {
disconnect_client(client, false, "failed to accept SSL");
return false;
}
break;
}
/* reject SSL attempt */
slog_noise(client, "P: nak");
if (!sbuf_answer(&client->sbuf, "N", 1)) {
disconnect_client(client, false, "failed to nak SSL");
return false;
}
break;
case PKT_GSSENCREQ:
/* reject GSS encryption attempt */
slog_noise(client, "C: req GSS enc");
if (!sbuf_answer(&client->sbuf, "N", 1)) {
disconnect_client(client, false, "failed to nak GSS enc");
return false;
}
break;
case PKT_STARTUP_V2:
disconnect_client(client, true, "old V2 protocol not supported");
return false;
case PKT_STARTUP:
/* require SSL except on unix socket */
if (client_accept_sslmode >= SSLMODE_REQUIRE && !client->sbuf.tls && !is_unix) {
disconnect_client(client, true, "SSL required");
return false;
}
if (client->pool && !client->wait_for_user_conn && !client->wait_for_user) {
disconnect_client(client, true, "client re-sent startup pkt");
return false;
}
if (client->wait_for_user) {
client->wait_for_user = false;
if (!finish_set_pool(client, false))
return false;
} else if (!decide_startup_pool(client, pkt)) {
return false;
}
break;
case 'p': /* PasswordMessage, SASLInitialResponse, or SASLResponse */
/* too early */
if (!client->login_user) {
disconnect_client(client, true, "client password pkt before startup packet");
return false;
}
if (client->client_auth_type == AUTH_SCRAM_SHA_256) {
const char *mech;
uint32_t length;
const uint8_t *data;
if (!client->scram_state.server_nonce) {
/* process as SASLInitialResponse */
if (!mbuf_get_string(&pkt->data, &mech))
return false;
slog_debug(client, "C: selected SASL mechanism: %s", mech);
if (strcmp(mech, "SCRAM-SHA-256") != 0) {
disconnect_client(client, true, "client selected an invalid SASL authentication mechanism");
return false;
}
if (!mbuf_get_uint32be(&pkt->data, &length))
return false;
if (!mbuf_get_bytes(&pkt->data, length, &data))
return false;
if (!scram_client_first(client, length, data)) {
disconnect_client(client, true, "SASL authentication failed");
return false;
}
} else {
/* process as SASLResponse */
length = mbuf_avail_for_read(&pkt->data);
if (!mbuf_get_bytes(&pkt->data, length, &data))
return false;
if (scram_client_final(client, length, data)) {
/* save SCRAM keys for user */
if (!client->scram_state.adhoc && !client->db->fake) {
memcpy(client->pool->user->scram_ClientKey,
client->scram_state.ClientKey,
sizeof(client->scram_state.ClientKey));
memcpy(client->pool->user->scram_ServerKey,
client->scram_state.ServerKey,
sizeof(client->scram_state.ServerKey));
client->pool->user->has_scram_keys = true;
}
free_scram_state(&client->scram_state);
if (!finish_client_login(client))
return false;
}
else {
disconnect_client(client, true, "SASL authentication failed");
return false;
}
}
} else {
/* process as PasswordMessage */
ok = mbuf_get_string(&pkt->data, &passwd);
if (ok) {
/*
* Don't allow an empty password; see
* PostgreSQL recv_password_packet().
*/
if (!*passwd) {
disconnect_client(client, true, "empty password returned by client");
return false;
}
if (client->client_auth_type == AUTH_PAM) {
if (!sbuf_pause(&client->sbuf)) {
disconnect_client(client, true, "pause failed");
return false;
}
pam_auth_begin(client, passwd);
return false;
}
if (check_client_passwd(client, passwd)) {
if (!finish_client_login(client))
return false;
} else {
disconnect_client(client, true, "password authentication failed");
return false;
}
}
}
break;
case PKT_CANCEL:
if (mbuf_avail_for_read(&pkt->data) == BACKENDKEY_LEN
&& mbuf_get_bytes(&pkt->data, BACKENDKEY_LEN, &key))
{
memcpy(client->cancel_key, key, BACKENDKEY_LEN);
accept_cancel_request(client);
} else {
disconnect_client(client, false, "bad cancel request");
}