diff options
Diffstat (limited to 'main2.c')
| -rw-r--r-- | main2.c | 145 |
1 files changed, 139 insertions, 6 deletions
@@ -211,6 +211,7 @@ struct next_req_domain { u_int8_t *dest; uint16_t port; u_int8_t *_printable_dest; + u_int8_t _domain_length; }; struct socks5_session { @@ -231,6 +232,12 @@ struct fd_bridge { }; +struct dns_resolve_result { + int atyp; + u_int8_t addrbuf[16]; /* ipv4 and ipv6 is allowed */ + +}; + volatile int g_need_exit = 0; static void review_config(struct runtime_opts *r_opts) @@ -248,6 +255,7 @@ static void parse_domain_socks5_req(char* buf, struct next_req_domain *next_req_ next_req_domain->atyp = buf[3]; domain_length = buf[4]; + next_req_domain->_domain_length = domain_length; next_req_domain->dest = (u_int8_t*)malloc(domain_length); next_req_domain->_printable_dest = (u_int8_t*)malloc(domain_length + 1); @@ -679,7 +687,7 @@ static void socks5_handshake(int fd, char* buf, struct socks5_session *socks5_se // } -static int socks5_send_connstate(int fd, u_int8_t state, u_int8_t atyp, u_int8_t *addr, uint16_t port) +static int socks5_send_connstate(int fd, u_int8_t state, u_int8_t atyp, u_int8_t *addr, uint16_t port, int domainlength) { int ret = 0; size_t addr_off, total_send_len; @@ -701,6 +709,14 @@ static int socks5_send_connstate(int fd, u_int8_t state, u_int8_t atyp, u_int8_t memcpy(buf + 4, addr, 4); memcpy(buf + 4 + 16, &port, 2); total_send_len = 4 + 16 + 2; + } else if (atyp == 3) { + memcpy(buf + 5, &domainlength, 1); // pass domainlength + + // for(int i = 0; i < domainlength; i++) { + memcpy(buf + 6 , addr, domainlength); + // } + memcpy(buf + 6 + domainlength + 1, &port, 2); + total_send_len = 6 + domainlength + 2; } @@ -810,6 +826,7 @@ static int create_server2server_conn(int *fdptr, int atyp, char* straddr, u_int1 socklen_t len = sizeof(struct sockaddr_in); ret = connect(tcpfd, (struct sockaddr*)&serv_addr, len); + if (ret == -1) { ret = errno; @@ -862,6 +879,96 @@ static int create_server2server_conn(int *fdptr, int atyp, char* straddr, u_int1 return 0; } +/* + * return 0 on succeed + +*/ + +static int _resolve_dns_and_tryconnect_loop(struct addrinfo *res, int *target_fd, + int port, struct dns_resolve_result *dns_result) +{ + char buf[NI_MAXHOST]; + void *ptr; + int ret = 0; + + while(res) { + memset(buf, 0, NI_MAXHOST); + + /* atyp 4 */ + if (res->ai_family == AF_INET) { + ptr = &((struct sockaddr_in*)res->ai_addr)->sin_addr; + + inet_ntop(AF_INET, ptr, buf, NI_MAXHOST); + + ret = create_server2server_conn(target_fd, 1, buf, port); + if (ret == 0) { + log_debug("ip resolved: %s", buf); + + dns_result->atyp = 1; + memcpy(dns_result->addrbuf, ptr, 4); + + return ret; + } + + } else if (res->ai_family == AF_INET6) { + ptr = &((struct sockaddr_in6*)res->ai_addr)->sin6_addr; + + inet_ntop(AF_INET6, ptr, buf, NI_MAXHOST); + log_debug("ip resolved: %s", buf); + + + ret = create_server2server_conn(target_fd, 4, buf, port); + + /* connection succesfull */ + if (ret == 0) { + log_debug("ip resolved: %s", buf); + + dns_result->atyp = 4; + memcpy(dns_result->addrbuf, ptr, 4); + return ret; + } + + + } + + res = res->ai_next; + + } + + return -1; +} + +/* + * return + * -1 resolve failed + */ + +static int resolve_dns(u_int8_t* domainname, int *target_fd, int port, struct dns_resolve_result *dns_result) +{ + struct addrinfo req_field; + void *ptr; + int ret = 0; + memset(&req_field, 0, sizeof(struct addrinfo)); + + struct addrinfo *res, *i; + /* try ipv4 first */ + + req_field.ai_family = AF_UNSPEC; + req_field.ai_socktype = SOCK_DGRAM; + + ret = getaddrinfo((char*)domainname, NULL, &req_field, &res); + if (ret != 0) { + perror("getaddrinfo"); + return -1; + } + + return _resolve_dns_and_tryconnect_loop(res, target_fd, port, dns_result); + + +} + + + // static int read_fd(int fd, u_int8_t *buf, size_t sizeofbuf, size_t sizeof_read) // { // int ret = 0; @@ -1267,8 +1374,8 @@ static int start_unpack_packet_no_epl(int fd, void* reserved, struct socks5_sess free(straddr); if (ret == 0) { - socks5_send_connstate(fd, 0, next_req->atyp, next_req->dest, - next_req->port); + socks5_send_connstate(fd, 0, 1, next_req->dest, + next_req->port, 0); start_exchange_data2(fd, cur_conn_clientfd); // if (exc_ret == 1) { @@ -1278,7 +1385,8 @@ static int start_unpack_packet_no_epl(int fd, void* reserved, struct socks5_sess // } } else { socks5_send_connstate(fd, 3, next_req->atyp, next_req->dest, - next_req->port); + next_req->port, 0); + return 0; } } else if (buf[3] == 4) { struct next_req_ipv6 *next_req = (struct next_req_ipv6*)buf; @@ -1300,7 +1408,7 @@ static int start_unpack_packet_no_epl(int fd, void* reserved, struct socks5_sess if (ret == 0) { socks5_send_connstate(fd, 0, next_req->atyp, next_req->dest, - next_req->port); + next_req->port, 0); start_exchange_data2(fd, cur_conn_clientfd); // if (exc_ret == 1) { @@ -1310,15 +1418,40 @@ static int start_unpack_packet_no_epl(int fd, void* reserved, struct socks5_sess // } } else { socks5_send_connstate(fd, 3, next_req->atyp, next_req->dest, - next_req->port); + next_req->port, 0); + return 0; } } else if (buf[3] == 3) { struct next_req_domain next_req; + struct dns_resolve_result dns_result; + parse_domain_socks5_req(buf, &next_req); + int cur_conn_clientfd = 0; + log_debug("SOCKS_REQ ver: %c; CMD: %s; type: %s; domain: %s:%d", buf[0], cmd2str(next_req.cmd), ip2str(next_req.atyp), next_req._printable_dest, ntohs(next_req.port)); + + + ret = resolve_dns(next_req._printable_dest, &cur_conn_clientfd, next_req.port, &dns_result); + + if (ret == 0) { + + socks5_send_connstate(fd, 0, dns_result.atyp, dns_result.addrbuf, + next_req.port, next_req._domain_length); + + start_exchange_data2(fd, cur_conn_clientfd); + // if (exc_ret == 1) { + // close(cur_conn_clientfd); + // close(fd); + return 0; + // } + } else { + socks5_send_connstate(fd, 3, next_req.atyp, next_req.dest, + next_req.port, next_req._domain_length); + return 0; + } } } }while (ret != 0); |