diff options
Diffstat (limited to 'package/ead/src/ead-client.c')
| -rw-r--r-- | package/ead/src/ead-client.c | 405 |
1 files changed, 405 insertions, 0 deletions
diff --git a/package/ead/src/ead-client.c b/package/ead/src/ead-client.c new file mode 100644 index 000000000..111dc8ac6 --- /dev/null +++ b/package/ead/src/ead-client.c @@ -0,0 +1,405 @@ +/* + * Client for the Emergency Access Daemon + * Copyright (C) 2008 Felix Fietkau <nbd@openwrt.org> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 + * as published by the Free Software Foundation + * + * 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. + */ + +#include <sys/types.h> +#include <sys/socket.h> +#include <sys/time.h> +#include <netinet/in.h> +#include <stdio.h> +#include <stddef.h> +#include <stdint.h> +#include <stdlib.h> +#include <stdbool.h> +#include <string.h> +#include <fcntl.h> +#include <unistd.h> +#include <t_pwd.h> +#include <t_read.h> +#include <t_sha.h> +#include <t_defines.h> +#include <t_client.h> +#include "ead.h" +#include "ead-crypt.h" + +#include "pw_encrypt_md5.c" + +#define EAD_TIMEOUT 400 +#define EAD_TIMEOUT_LONG 2000 + +static char msgbuf[1500]; +static struct ead_msg *msg = (struct ead_msg *) msgbuf; +static uint16_t nid = 0xffff; +struct sockaddr_in local, remote; +static int s = 0; +static int sockflags; + +static unsigned char *skey = NULL; +static unsigned char bbuf[MAXPARAMLEN]; +static unsigned char saltbuf[MAXSALTLEN]; +static char *username = NULL; +static char password[MAXPARAMLEN] = ""; +static char pw_md5[MD5_OUT_BUFSIZE]; +static char pw_salt[MAXSALTLEN]; + +static struct t_client *tc = NULL; +static struct t_num salt = { .data = saltbuf }; +static struct t_num *A, B; +static struct t_preconf *tcp; +static int auth_type = EAD_AUTH_DEFAULT; +static int timeout = EAD_TIMEOUT; + +static void +set_nonblock(int enable) +{ + if (enable == !!(sockflags & O_NONBLOCK)); + return; + + sockflags ^= O_NONBLOCK; + fcntl(s, F_SETFL, sockflags); +} + +static int +send_packet(int type, bool (*handler)(void), unsigned int max) +{ + struct timeval tv; + fd_set fds; + int nfds; + int len; + int res = 0; + + type = htonl(type); + set_nonblock(0); + sendto(s, msgbuf, sizeof(struct ead_msg) + ntohl(msg->len), 0, (struct sockaddr *) &remote, sizeof(remote)); + set_nonblock(1); + + tv.tv_sec = timeout / 1000; + tv.tv_usec = (timeout % 1000) * 1000; + + FD_ZERO(&fds); + do { + FD_SET(s, &fds); + nfds = select(s + 1, &fds, NULL, NULL, &tv); + + if (nfds <= 0) + break; + + if (!FD_ISSET(s, &fds)) + break; + + len = read(s, msgbuf, sizeof(msgbuf)); + if (len < 0) + break; + + if (len < sizeof(struct ead_msg)) + continue; + + if (len < sizeof(struct ead_msg) + ntohl(msg->len)) + continue; + + if (msg->magic != htonl(EAD_MAGIC)) + continue; + + if ((nid != 0xffff) && (ntohs(msg->nid) != nid)) + continue; + + if (msg->type != type) + continue; + + if (handler()) + res++; + + if ((max > 0) && (res >= max)) + break; + } while (1); + + return res; +} + +static void +prepare_password(void) +{ + switch(auth_type) { + case EAD_AUTH_DEFAULT: + break; + case EAD_AUTH_MD5: + md5_crypt(pw_md5, (unsigned char *) password, (unsigned char *) pw_salt); + strncpy(password, pw_md5, sizeof(password)); + break; + } +} + +static bool +handle_pong(void) +{ + struct ead_msg_pong *pong = EAD_DATA(msg, pong); + int len = msg->len - sizeof(struct ead_msg_pong); + + pong->name[len] = 0; + auth_type = ntohs(pong->auth_type); + if (nid == 0xffff) + printf("%04x: %s\n", ntohs(msg->nid), pong->name); + return true; +} + +static bool +handle_prime(void) +{ + struct ead_msg_salt *sb = EAD_DATA(msg, salt); + + salt.len = sb->len; + memcpy(salt.data, sb->salt, salt.len); + + if (auth_type == EAD_AUTH_MD5) { + memcpy(pw_salt, sb->ext_salt, MAXSALTLEN); + pw_salt[MAXSALTLEN - 1] = 0; + } + + tcp = t_getpreparam(sb->prime); + tc = t_clientopen(username, &tcp->modulus, &tcp->generator, &salt); + if (!tc) { + fprintf(stderr, "Client open failed\n"); + return false; + } + + return true; +} + +static bool +handle_b(void) +{ + struct ead_msg_number *num = EAD_DATA(msg, number); + int len = ntohl(msg->len) - sizeof(struct ead_msg_number); + + B.data = bbuf; + B.len = len; + memcpy(bbuf, num->data, len); + return true; +} + +static bool +handle_none(void) +{ + return true; +} + +static bool +handle_done_auth(void) +{ + struct ead_msg_auth *auth = EAD_DATA(msg, auth); + if (t_clientverify(tc, auth->data) != 0) { + fprintf(stderr, "Client auth verify failed\n"); + return false; + } + return true; +} + +static bool +handle_cmd_data(void) +{ + struct ead_msg_cmd_data *cmd = EAD_ENC_DATA(msg, cmd_data); + int datalen = ead_decrypt_message(msg) - sizeof(struct ead_msg_cmd_data); + + if (datalen < 0) + return false; + + if (datalen > 0) { + write(1, cmd->data, datalen); + } + + return !!cmd->done; +} +static int +send_ping(void) +{ + msg->type = htonl(EAD_TYPE_PING); + msg->len = 0; + return send_packet(EAD_TYPE_PONG, handle_pong, (nid == 0xffff ? 0 : 1)); +} + +static int +send_username(void) +{ + msg->type = htonl(EAD_TYPE_SET_USERNAME); + msg->len = htonl(sizeof(struct ead_msg_user)); + strcpy(EAD_DATA(msg, user)->username, username); + return send_packet(EAD_TYPE_ACK_USERNAME, handle_none, 1); +} + +static int +get_prime(void) +{ + msg->type = htonl(EAD_TYPE_GET_PRIME); + msg->len = 0; + return send_packet(EAD_TYPE_PRIME, handle_prime, 1); +} + +static int +send_a(void) +{ + struct ead_msg_number *num = EAD_DATA(msg, number); + A = t_clientgenexp(tc); + msg->type = htonl(EAD_TYPE_SEND_A); + msg->len = htonl(sizeof(struct ead_msg_number) + A->len); + memcpy(num->data, A->data, A->len); + return send_packet(EAD_TYPE_SEND_B, handle_b, 1); +} + +static int +send_auth(void) +{ + struct ead_msg_auth *auth = EAD_DATA(msg, auth); + + prepare_password(); + t_clientpasswd(tc, password); + skey = t_clientgetkey(tc, &B); + if (!skey) + return 0; + + ead_set_key(skey); + msg->type = htonl(EAD_TYPE_SEND_AUTH); + msg->len = htonl(sizeof(struct ead_msg_auth)); + memcpy(auth->data, t_clientresponse(tc), sizeof(auth->data)); + return send_packet(EAD_TYPE_DONE_AUTH, handle_done_auth, 1); +} + +static int +send_command(const char *command) +{ + struct ead_msg_cmd *cmd = EAD_ENC_DATA(msg, cmd); + + msg->type = htonl(EAD_TYPE_SEND_CMD); + cmd->type = htons(EAD_CMD_NORMAL); + cmd->timeout = htons(10); + strncpy((char *)cmd->data, command, 1024); + ead_encrypt_message(msg, sizeof(struct ead_msg_cmd) + strlen(command) + 1); + return send_packet(EAD_TYPE_RESULT_CMD, handle_cmd_data, 1); +} + + +static int +usage(const char *prog) +{ + fprintf(stderr, "Usage: %s <node> <username>[:<password>]\n" + "\n" + "\n<node>: Node ID (4 digits hex)\n" + "\n<username>: Username to authenticate with\n" + "\n" + "\nPassing no arguments shows a list of active nodes on the network\n" + "\n", prog); + return -1; +} + + +int main(int argc, char **argv) +{ + int val = 1; + char *st = NULL; + const char *command = NULL; + + msg->magic = htonl(EAD_MAGIC); + msg->tid = 0; + + memset(&local, 0, sizeof(local)); + memset(&remote, 0, sizeof(remote)); + + remote.sin_family = AF_INET; + remote.sin_addr.s_addr = 0xffffffff; + remote.sin_port = htons(EAD_PORT); + + local.sin_family = AF_INET; + local.sin_addr.s_addr = INADDR_ANY; + local.sin_port = 0; + + switch(argc) { + case 4: + command = argv[3]; + /* fall through */ + case 3: + username = argv[2]; + st = strchr(username, ':'); + if (st) { + *st = 0; + st++; + strncpy(password, st, sizeof(password)); + password[sizeof(password) - 1] = 0; + /* hide command line password */ + memset(st, 0, strlen(st)); + } + /* fall through */ + case 2: + nid = strtoul(argv[1], &st, 16); + if (st && st[0] != 0) + return usage(argv[0]); + /* fall through */ + case 1: + break; + default: + return usage(argv[0]); + } + + msg->nid = htons(nid); + s = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP); + if (s < 0) { + perror("socket"); + return -1; + } + + setsockopt(s, SOL_SOCKET, SO_BROADCAST, &val, sizeof(val)); + + if (bind(s, (struct sockaddr *)&local, sizeof(local)) < 0) { + perror("bind"); + return -1; + } + sockflags = fcntl(s, F_GETFL); + + if (!send_ping()) { + fprintf(stderr, "No devices found\n"); + return 1; + } + + if (nid == 0xffff) + return 0; + + if (!username || !password[0]) + return 0; + + if (!send_username()) { + fprintf(stderr, "Device did not accept user name\n"); + return 1; + } + if (!get_prime()) { + fprintf(stderr, "Failed to get user password info\n"); + return 1; + } + + timeout = EAD_TIMEOUT_LONG; + if (!send_a()) { + fprintf(stderr, "Failed to send local authentication data\n"); + return 1; + } + if (!send_auth()) { + fprintf(stderr, "Authentication failed\n"); + return 1; + } + if (!command) { + fprintf(stderr, "Authentication succesful\n"); + return 0; + } + if (!send_command(command)) { + fprintf(stderr, "Command failed\n"); + return 1; + } + + return 0; +} |