diff options
Diffstat (limited to 'networking')
| -rw-r--r-- | networking/nslookup.c | 79 |
1 files changed, 40 insertions, 39 deletions
diff --git a/networking/nslookup.c b/networking/nslookup.c index 8791b5efe..1c75bb570 100644 --- a/networking/nslookup.c +++ b/networking/nslookup.c @@ -31,6 +31,8 @@ #include <sys/socket.h> #include <sys/types.h> #include <netinet/in.h> +#include <resolv.h> +#include <arpa/inet.h> #include "busybox.h" /* @@ -39,19 +41,8 @@ | | [ TODO ] | + find out how to use non-default name servers - | + find out how the real nslookup gets the default name server */ -/* I have to see how the real nslookup does this. - * I could dig through /etc/resolv.conf, but is there a - * better (programatic) way? - */ -static inline void server_print(void) -{ - printf("Server: %s\n", "default"); - printf("Address: %s\n\n", "default"); -} - /* only works for IPv4 */ static int addr_fprint(char *addr) { @@ -68,24 +59,6 @@ static int addr_fprint(char *addr) return 0; } -/* changes a c-string matching the perl regex \d+\.\d+\.\d+\.\d+ - * into a u_int32_t - */ -static u_int32_t str_to_addr(const char *addr) -{ - u_int32_t split[4]; - u_int32_t ip; - - sscanf(addr, "%d.%d.%d.%d", - &split[0], &split[1], &split[2], &split[3]); - - /* assuming sscanf worked */ - ip = (split[0] << 24) | - (split[1] << 16) | (split[2] << 8) | (split[3]); - - return htonl(ip); -} - /* takes the NULL-terminated array h_addr_list, and * prints its contents appropriately */ @@ -116,15 +89,6 @@ static int addr_list_fprint(char **h_addr_list) return 0; } -/* gethostbyaddr wrapper */ -static struct hostent *gethostbyaddr_wrapper(const char *address) -{ - struct in_addr addr; - - addr.s_addr = str_to_addr(address); - return gethostbyaddr((char *) &addr, 4, AF_INET); /* IPv4 only for now */ -} - /* print the results as nslookup would */ static struct hostent *hostent_fprint(struct hostent *host) { @@ -137,6 +101,42 @@ static struct hostent *hostent_fprint(struct hostent *host) return host; } +/* changes a c-string matching the perl regex \d+\.\d+\.\d+\.\d+ + * into a u_int32_t + */ +static u_int32_t str_to_addr(const char *addr) +{ + u_int32_t split[4]; + u_int32_t ip; + + sscanf(addr, "%d.%d.%d.%d", + &split[0], &split[1], &split[2], &split[3]); + + /* assuming sscanf worked */ + ip = (split[0] << 24) | + (split[1] << 16) | (split[2] << 8) | (split[3]); + + return htonl(ip); +} + +/* gethostbyaddr wrapper */ +static struct hostent *gethostbyaddr_wrapper(const char *address) +{ + struct in_addr addr; + + addr.s_addr = str_to_addr(address); + return gethostbyaddr((char *) &addr, 4, AF_INET); /* IPv4 only for now */ +} + +/* lookup the default nameserver and display it */ +static inline void server_print(void) +{ + struct sockaddr_in def = _res.nsaddr_list[0]; + char *ip = inet_ntoa(def.sin_addr); + + hostent_fprint(gethostbyaddr_wrapper(ip)); + printf("\n"); +} /* naive function to check whether char *s is an ip address */ static int is_ip_address(const char *s) @@ -160,6 +160,7 @@ int nslookup_main(int argc, char **argv) show_usage(); } + res_init(); server_print(); if (is_ip_address(argv[1])) { host = gethostbyaddr_wrapper(argv[1]); @@ -170,4 +171,4 @@ int nslookup_main(int argc, char **argv) return EXIT_SUCCESS; } -/* $Id: nslookup.c,v 1.22 2001/02/20 06:14:08 andersen Exp $ */ +/* $Id: nslookup.c,v 1.23 2001/06/12 22:21:24 andersen Exp $ */ |