MaxScale/modules/protocol/mysql_common.c

436 lines
11 KiB
C

/*
* This file is distributed as part of the SkySQL Gateway. It is free
* software: you can redistribute it and/or modify it under the terms of the
* GNU General Public License as published by the Free Software Foundation,
* version 2.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
* FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
* details.
*
* You should have received a copy of the GNU General Public License along with
* this program; if not, write to the Free Software Foundation, Inc., 51
* Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Copyright SkySQL Ab 2013
*/
/*
* MySQL Protocol common routines for client to gateway and gateway to backend
*
* Revision History
* Date Who Description
* 17/06/2013 Massimiliano Pinto Common MySQL protocol routines
* 02/06/2013 Massimiliano Pinto MySQL connect asynchronous phases
*/
#include "mysql_client_server_protocol.h"
extern int gw_read_backend_event(DCB* dcb);
extern int gw_write_backend_event(DCB *dcb);
extern int gw_MySQLWrite_backend(DCB *dcb, GWBUF *queue);
extern int gw_error_backend_event(DCB *dcb);
///////////////////////////////
// Initialize mysql protocol struct
///////////////////////////////////////
MySQLProtocol *gw_mysql_init(MySQLProtocol *data) {
MySQLProtocol *input = NULL;
if (input == NULL) {
// structure allocation
input = calloc(1, sizeof(MySQLProtocol));
if (input == NULL)
return NULL;
}
#ifdef MYSQL_CONN_DEBUG
fprintf(stderr, "gw_mysql_init() called\n");
#endif
return input;
}
//////////////////////////////////////
// close a connection if opened
// free data scructure for MySQLProtocol
//////////////////////////////////////
void gw_mysql_close(MySQLProtocol **ptr) {
MySQLProtocol *conn = *ptr;
if (*ptr == NULL)
return;
#ifdef MYSQL_CONN_DEBUG
fprintf(stderr, "Closing MySQL connection %i, [%s]\n", conn->fd, conn->scramble);
#endif
if (conn->fd > 0) {
//COM_QUIT will not be sent here, but from the caller of this routine!
#ifdef MYSQL_CONN_DEBUG
fprintf(stderr, "mysqlgw_mysql_close() called for %i\n", conn->fd);
#endif
close(conn->fd);
} else {
#ifdef MYSQL_CONN_DEBUG
fprintf(stderr, "mysqlgw_mysql_close() called, no socket %i\n", conn->fd);
#endif
}
free(*ptr);
*ptr = NULL;
#ifdef MYSQL_CONN_DEBUG
fprintf(stderr, "mysqlgw_mysql_close() free(conn) done\n");
#endif
}
/**
* Read the backend server MySQL handshake
*
* @param conn MySQL protocol structure
* @return 0 on success, 1 on failure
*/
int gw_read_backend_handshake(MySQLProtocol *conn) {
GWBUF *head = NULL;
DCB *dcb = conn->descriptor;
int n = -1;
uint8_t *payload = NULL;
unsigned int packet_len = 0;
if ((n = dcb_read(dcb, &head)) != -1) {
dcb->state = DCB_STATE_PROCESSING;
if (head) {
payload = GWBUF_DATA(head);
packet_len = gw_mysql_get_byte3(payload);
// skip the 4 bytes header
payload += 4;
//Now decode mysql handshake
gw_decode_mysql_server_handshake(conn, payload);
conn->state = MYSQL_AUTH_SENT;
// consume all the data here
head = gwbuf_consume(head, gwbuf_length(head));
dcb->state = DCB_STATE_POLLING;
return 0;
}
}
return 1;
}
/**
* Decode mysql server handshake
*/
int gw_decode_mysql_server_handshake(MySQLProtocol *conn, uint8_t *payload) {
int server_protocol;
uint8_t *server_version_end = NULL;
uint16_t mysql_server_capabilities_one;
uint16_t mysql_server_capabilities_two;
unsigned long tid =0;
uint8_t scramble_data_1[8] = "";
uint8_t scramble_data_2[12] = "";
uint8_t capab_ptr[4];
int scramble_len;
uint8_t scramble[GW_MYSQL_SCRAMBLE_SIZE];
// Get server protocol
server_protocol= payload[0];
payload++;
// Get server version (string)
server_version_end = (uint8_t *) gw_strend((char*) payload);
payload = server_version_end + 1;
// get ThreadID
tid = gw_mysql_get_byte4(payload);
memcpy(&conn->tid, &tid, 4);
payload +=4;
// scramble_part 1
memcpy(scramble_data_1, payload, 8);
payload += 8;
// 1 filler
payload++;
mysql_server_capabilities_one = gw_mysql_get_byte2(payload);
//Get capabilities_part 1 (2 bytes) + 1 language + 2 server_status
payload +=5;
mysql_server_capabilities_two = gw_mysql_get_byte2(payload);
memcpy(&capab_ptr, &mysql_server_capabilities_one, 2);
// get capabilities part 2 (2 bytes)
memcpy(&(capab_ptr[2]), &mysql_server_capabilities_two, 2);
// 2 bytes shift
payload+=2;
// get scramble len
scramble_len = payload[0] -1;
// skip 10 zero bytes
payload += 11;
// copy the second part of the scramble
memcpy(scramble_data_2, payload, scramble_len - 8);
memcpy(scramble, scramble_data_1, 8);
memcpy(scramble + 8, scramble_data_2, scramble_len - 8);
// full 20 bytes scramble is ready
memcpy(conn->scramble, scramble, GW_MYSQL_SCRAMBLE_SIZE);
return 0;
}
/**
* Receive the MySQL authentication packet from backend, packet # is 2
*
* @param conn The MySQL protocol structure
* @return 0 for user authenticated or 1 for authentication failed
*/
int gw_receive_backend_auth(MySQLProtocol *conn) {
int rv = 1;
int n = -1;
GWBUF *head = NULL;
DCB *dcb = conn->descriptor;
uint8_t *ptr = NULL;
unsigned int packet_len = 0;
if ((n = dcb_read(dcb, &head)) != -1) {
dcb->state = DCB_STATE_PROCESSING;
if (head) {
ptr = GWBUF_DATA(head);
packet_len = gw_mysql_get_byte3(ptr);
// check if the auth is SUCCESFUL
if (ptr[4] == '\x00') {
// Auth is OK
rv = 0;
} else {
rv = 1;
}
// consume all the data here
head = gwbuf_consume(head, gwbuf_length(head));
}
}
dcb->state = DCB_STATE_POLLING;
return rv;
}
/**
* Write MySQL authentication packet to backend server
*
* @param conn MySQL protocol structure
* @param dbname The selected database
* @param user The selected user
* @param passwd The SHA1(real_password): Note real_password is unknown
* @return 0 on success, 1 on failure
*/
int gw_send_authentication_to_backend(char *dbname, char *user, uint8_t *passwd, MySQLProtocol *conn) {
int compress = 0;
int rv;
uint8_t *payload = NULL;
uint8_t *payload_start = NULL;
long bytes;
uint8_t client_scramble[GW_MYSQL_SCRAMBLE_SIZE];
uint8_t client_capabilities[4];
uint32_t server_capabilities;
uint32_t final_capabilities;
char dbpass[129]="";
GWBUF *buffer;
DCB *dcb;
char *curr_db = NULL;
uint8_t *curr_passwd = NULL;
if (strlen(dbname))
curr_db = dbname;
if (strlen((char *)passwd))
curr_passwd = passwd;
dcb = conn->descriptor;
#ifdef DEBUG_MYSQL_CONN
fprintf(stderr, ">> Sending credentials %s, %s, db %s\n", user, passwd, dbname);
#endif
// Zero the vars
memset(&server_capabilities, '\0', sizeof(server_capabilities));
memset(&final_capabilities, '\0', sizeof(final_capabilities));
final_capabilities = gw_mysql_get_byte4((uint8_t *)&server_capabilities);
final_capabilities |= GW_MYSQL_CAPABILITIES_PROTOCOL_41;
final_capabilities |= GW_MYSQL_CAPABILITIES_CLIENT;
if (compress) {
final_capabilities |= GW_MYSQL_CAPABILITIES_COMPRESS;
#ifdef DEBUG_MYSQL_CONN
fprintf(stderr, ">>>> Backend Connection with compression\n");
#endif
}
if (curr_passwd != NULL) {
uint8_t hash1[GW_MYSQL_SCRAMBLE_SIZE]="";
uint8_t hash2[GW_MYSQL_SCRAMBLE_SIZE]="";
uint8_t new_sha[GW_MYSQL_SCRAMBLE_SIZE]="";
// hash1 is the function input, SHA1(real_password)
memcpy(hash1, passwd, GW_MYSQL_SCRAMBLE_SIZE);
// hash2 is the SHA1(input data), where input_data = SHA1(real_password)
gw_sha1_str(hash1, GW_MYSQL_SCRAMBLE_SIZE, hash2);
// dbpass is the HEX form of SHA1(SHA1(real_password))
gw_bin2hex(dbpass, hash2, GW_MYSQL_SCRAMBLE_SIZE);
// new_sha is the SHA1(CONCAT(scramble, hash2)
gw_sha1_2_str(conn->scramble, GW_MYSQL_SCRAMBLE_SIZE, hash2, GW_MYSQL_SCRAMBLE_SIZE, new_sha);
// compute the xor in client_scramble
gw_str_xor(client_scramble, new_sha, hash1, GW_MYSQL_SCRAMBLE_SIZE);
}
if (curr_db == NULL) {
// without db
final_capabilities &= ~GW_MYSQL_CAPABILITIES_CONNECT_WITH_DB;
} else {
final_capabilities |= GW_MYSQL_CAPABILITIES_CONNECT_WITH_DB;
}
final_capabilities |= GW_MYSQL_CAPABILITIES_PLUGIN_AUTH;
gw_mysql_set_byte4(client_capabilities, final_capabilities);
// Protocol MySQL HandshakeResponse for CLIENT_PROTOCOL_41
// 4 bytes capabilities + 4 bytes max packet size + 1 byte charset + 23 '\0' bytes
// 4 + 4 + 1 + 23 = 32
bytes = 32;
bytes += strlen(user);
// the NULL
bytes++;
// next will be + 1 (scramble_len) + 20 (fixed_scramble) + 1 (user NULL term) + 1 (db NULL term)
if (curr_passwd != NULL) {
bytes++;
bytes += GW_MYSQL_SCRAMBLE_SIZE;
} else {
bytes++;
}
if (curr_db != NULL) {
bytes += strlen(curr_db);
bytes++;
}
bytes +=strlen("mysql_native_password");
bytes++;
// the packet header
bytes += 4;
// allocating the GWBUF
buffer = gwbuf_alloc(bytes);
payload = GWBUF_DATA(buffer);
// clearing data
memset(payload, '\0', bytes);
// save the start pointer
payload_start = payload;
// set packet # = 1
payload[3] = '\x01';
payload += 4;
// set client capabilities
memcpy(payload, client_capabilities, 4);
// set now the max-packet size
payload += 4;
gw_mysql_set_byte4(payload, 16777216);
// set the charset
payload += 4;
*payload = '\x08';
payload++;
// 23 bytes of 0
payload += 23;
// 4 + 4 + 4 + 1 + 23 = 36, this includes the 4 bytes packet header
memcpy(payload, user, strlen(user));
payload += strlen(user);
payload++;
if (curr_passwd != NULL) {
// set the auth-length
*payload = GW_MYSQL_SCRAMBLE_SIZE;
payload++;
//copy the 20 bytes scramble data after packet_buffer+36+user+NULL+1 (byte of auth-length)
memcpy(payload, client_scramble, GW_MYSQL_SCRAMBLE_SIZE);
payload += GW_MYSQL_SCRAMBLE_SIZE;
} else {
// skip the auth-length and write a NULL
payload++;
}
// if the db is not NULL append it
if (curr_db != NULL) {
memcpy(payload, curr_db, strlen(curr_db));
payload += strlen(curr_db);
payload++;
}
memcpy(payload, "mysql_native_password", strlen("mysql_native_password"));
payload += strlen("mysql_native_password");
payload++;
// put here the paylod size: bytes to write - 4 bytes packet header
gw_mysql_set_byte3(payload_start, (bytes-4));
// write to backend dcb
// ToDO: handle the EAGAIN | EWOULDBLOCK
rv = write(dcb->fd, GWBUF_DATA(buffer), bytes);
gwbuf_consume(buffer, bytes);
conn->state = MYSQL_AUTH_RECV;
if (rv < 0)
return rv;
else
return 0;
}
/////