From c538bd0b6d2dcf9072bd633ffbf271c3362befaa Mon Sep 17 00:00:00 2001 From: Bjorn Andersson Date: Sat, 10 Feb 2007 22:17:11 +0000 Subject: [PATCH] the seed wasnt saved in the server between it was sent to the client and the client logged in, extracted function for sending version_responses --- src/iodined.c | 68 ++++++++++++++++++++++++++++++++++----------------- 1 file changed, 46 insertions(+), 22 deletions(-) diff --git a/src/iodined.c b/src/iodined.c index 517db52..e1ef88b 100644 --- a/src/iodined.c +++ b/src/iodined.c @@ -67,68 +67,91 @@ sigint(int sig) static int tunnel_tun(int tun_fd, int dns_fd) { + unsigned long outlen; char out[64*1024]; char in[64*1024]; - long outlen; int read; if ((read = read_tun(tun_fd, in, sizeof(in))) <= 0) return 0; outlen = sizeof(out); - compress2(out, &outlen, in, read, 9); + compress2((uint8_t*)out, &outlen, (uint8_t*)in, read, 9); memcpy(outpacket.data, out, outlen); outpacket.len = outlen; return outlen; } +typedef enum { + VERSION_ACK, + VERSION_NACK +} version_ack_t; + +static void +send_version_response(int fd, version_ack_t ack, uint32_t payload) +{ + char out[8]; + + switch (ack) { + case VERSION_ACK: + strncpy(out, "VACK", sizeof(out)); + break; + case VERSION_NACK: + strncpy(out, "VNAK", sizeof(out)); + break; + } + + out[4] = ((payload >> 24) & 0xff); + out[5] = ((payload >> 16) & 0xff); + out[6] = ((payload >> 8) & 0xff); + out[7] = ((payload) & 0xff); + + write_dns(fd, &q, out, 8); +} + static int tunnel_dns(int tun_fd, int dns_fd) { struct in_addr clientip; + unsigned long outlen; struct in_addr myip; char logindata[16]; char out[64*1024]; char in[64*1024]; + static int seed; char *tmp[2]; - long outlen; + int version; int read; int code; - int version; - int seed; - int nseed; if ((read = read_dns(dns_fd, &q, in, sizeof(in))) <= 0) return 0; if(in[0] == 'V' || in[0] == 'v') { /* Version greeting, compare and send ack/nak */ - if (read >= 5) { + if (read > 4) { /* Received V + 32bits version */ - memcpy(&version, in + 1, 4); - version = ntohl(version); + + version = (((in[1] & 0xff) << 24) | + ((in[2] & 0xff) << 16) | + ((in[3] & 0xff) << 8) | + ((in[4] & 0xff))); + if (version == VERSION) { seed = rand(); - nseed = htonl(seed); - strncpy(out, "VACK", sizeof(out)); - memcpy(out+4, &nseed, 4); - write_dns(dns_fd, &q, out, 8); + + send_version_response(dns_fd, VERSION_ACK, seed); } else { - version = htonl(VERSION); - strncpy(out, "VNAK", sizeof(out)); - memcpy(out+4, &version, 4); - write_dns(dns_fd, &q, out, 8); + send_version_response(dns_fd, VERSION_NACK, VERSION); } } else { - version = htonl(VERSION); - strncpy(out, "VNAK", sizeof(out)); - memcpy(out+4, &version, 4); - write_dns(dns_fd, &q, out, 8); + send_version_response(dns_fd, VERSION_NACK, VERSION); } } else if(in[0] == 'L' || in[0] == 'l') { /* Login phase, handle auth */ login_calculate(logindata, 16, password, seed); + if (read >= 17 && (memcmp(logindata, in+1, 16) == 0)) { /* Login ok, send ip/mtu info */ myip.s_addr = my_ip; @@ -173,7 +196,8 @@ tunnel_dns(int tun_fd, int dns_fd) if (code & 1) { outlen = sizeof(out); - uncompress(out, &outlen, packetbuf.data, packetbuf.len); + uncompress((uint8_t*)out, &outlen, + (uint8_t*)packetbuf.data, packetbuf.len); write_tun(tun_fd, out, outlen);