diff options
Diffstat (limited to 'libnet/dns.c')
| -rw-r--r-- | libnet/dns.c | 35 |
1 files changed, 31 insertions, 4 deletions
diff --git a/libnet/dns.c b/libnet/dns.c index b35eb72..fc6b06f 100644 --- a/libnet/dns.c +++ b/libnet/dns.c @@ -1,7 +1,11 @@ // MIT License, Copyright (c) 2020 Marvin Borner +// TODO: Less magic, auto xld splitting +// TODO: DNS cache #include <def.h> #include <mem.h> +#include <net.h> +#include <print.h> #include <random.h> #include <socket.h> #include <str.h> @@ -36,13 +40,29 @@ static void dns_make_packet(struct dns_packet *packet, const char *name, const c packet->data[(u8)strlen(name) + (u8)strlen(tld) + 6] = 0x01; // IN } -void dns_request(const char *name, const char *tld) +static u32 dns_handle_packet(struct dns_packet *packet) +{ + u16 flags = htons(packet->flags); + u8 reply_code = flags & 0xf; + if (reply_code != DNS_NOERROR) { + printf("DNS error: %d\n", reply_code); + return 0; + } + + u8 *start = &packet->data[1] + strlen((char *)&packet->data[1]); + printf("TTL of %s: %ds\n", &packet->data[1], (u32)start[14]); + u8 *ip = &start[17]; + printf("IP: %d.%d.%d.%d\n", ip[0], ip[1], ip[2], ip[3]); + return ip(ip[0], ip[1], ip[2], ip[3]); +} + +u32 dns_request(const char *name, const char *tld) { struct socket *socket = net_open(S_UDP); - if (socket) - socket->src_port = 50053; + /* if (socket) */ + /* socket->src_port = 50053; */ if (!socket || !net_connect(socket, dns_ip_addr, 53)) - return; + return 0; u32 length = sizeof(struct dns_packet) + strlen(name) + strlen(tld) + 7; // TODO: 7 :) struct dns_packet *packet = malloc(length); @@ -50,4 +70,11 @@ void dns_request(const char *name, const char *tld) dns_make_packet(packet, name, tld); net_send(socket, packet, length); free(packet); + + u8 buf[128] = { 0 }; + int l = net_receive(socket, buf, 128); + if (l > 0) + return dns_handle_packet((void *)buf); + else + return 0; } |