X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;ds=sidebyside;f=nslookup.c;h=8791b5efee4aa66d998d52bc874b44863e65a3fc;hb=8bb7df49c24de71f28b47eb2e3b86fb5b2e9d42a;hp=0a2a57437b164775d3d8f863d2880417843538ae;hpb=b332e779e6709908b203054c687cd1dec660f50e;p=oweals%2Fbusybox.git diff --git a/nslookup.c b/nslookup.c index 0a2a57437..8791b5efe 100644 --- a/nslookup.c +++ b/nslookup.c @@ -1,8 +1,8 @@ +/* vi: set sw=4 ts=4: */ /* * Mini nslookup implementation for busybox * - * - * Copyright (C) 2000 by Lineo, inc. + * Copyright (C) 1999,2000,2001 by Lineo, inc. * Written by John Beppu * * This program is free software; you can redistribute it and/or modify @@ -21,148 +21,153 @@ * */ -#include "internal.h" #include #include #include #include +#include #include #include #include #include +#include "busybox.h" +/* + | I'm only implementing non-interactive mode; + | I totally forgot nslookup even had an interactive mode. + | + | [ TODO ] + | + find out how to use non-default name servers + | + find out how the real nslookup gets the default name server + */ -static const char nslookup_usage[] = -"only implementing non-interactive mode\n" -"I totally forgot nslookup even had an interactive mode\n" -; - - -/* */ -static void -server_fprint(FILE *dst) +/* 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) { - fprintf(dst, "Server: %s\n", "something"); - fprintf(dst, "Address: %s\n\n", "something"); + printf("Server: %s\n", "default"); + printf("Address: %s\n\n", "default"); } /* only works for IPv4 */ -static int -addr_fprint(char *addr, FILE *dst) +static int addr_fprint(char *addr) { - uint8_t split[4]; - uint32_t ip; - uint32_t *x = (uint32_t *) addr; - - ip = ntohl(*x); - split[0] = (ip & 0xff000000) >> 24; - split[1] = (ip & 0x00ff0000) >> 16; - split[2] = (ip & 0x0000ff00) >> 8; - split[3] = (ip & 0x000000ff); - fprintf ( - dst, "%d.%d.%d.%d", - split[0], split[1], split[2], split[3] - ); - return 0; + u_int8_t split[4]; + u_int32_t ip; + u_int32_t *x = (u_int32_t *) addr; + + ip = ntohl(*x); + split[0] = (ip & 0xff000000) >> 24; + split[1] = (ip & 0x00ff0000) >> 16; + split[2] = (ip & 0x0000ff00) >> 8; + split[3] = (ip & 0x000000ff); + printf("%d.%d.%d.%d", split[0], split[1], split[2], split[3]); + return 0; } -/* */ -static uint32_t -str_to_addr(const char *addr) +/* 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) { - uint32_t split[4]; - uint32_t ip; + u_int32_t split[4]; + u_int32_t ip; - sscanf(addr, "%d.%d.%d.%d", - &split[0], &split[1], &split[2], &split[3]); + 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]); + /* assuming sscanf worked */ + ip = (split[0] << 24) | + (split[1] << 16) | (split[2] << 8) | (split[3]); - return htonl(ip); + return htonl(ip); } -/* */ -static int -addr_list_fprint(char **h_addr_list, FILE *dst) +/* takes the NULL-terminated array h_addr_list, and + * prints its contents appropriately + */ +static int addr_list_fprint(char **h_addr_list) { - int i; - char *addr_string = (h_addr_list[1]) - ? "Addresses" - : "Address"; - - fprintf(dst, "%s: ", addr_string); - for (i = 0; h_addr_list[i]; i++) { - addr_fprint(h_addr_list[i], dst); - if (h_addr_list[i+1]) { - fprintf(dst, ", "); + int i, j; + char *addr_string = (h_addr_list[1]) + ? "Addresses: " : "Address: "; + + printf("%s ", addr_string); + for (i = 0, j = 0; h_addr_list[i]; i++, j++) { + addr_fprint(h_addr_list[i]); + + /* real nslookup does this */ + if (j == 4) { + if (h_addr_list[i + 1]) { + printf("\n "); + } + j = 0; + } else { + if (h_addr_list[i + 1]) { + printf(", "); + } + } + } - } - fprintf(dst,"\n"); - return 0; + printf("\n"); + return 0; } -/* */ -static struct hostent * -lookup_by_name(const char *hostname) +/* gethostbyaddr wrapper */ +static struct hostent *gethostbyaddr_wrapper(const char *address) { - struct hostent *host; - - host = gethostbyname(hostname); - if (host) { - fprintf(stdout, "Name: %s\n", host->h_name); - addr_list_fprint(host->h_addr_list, stdout); - } else { - herror("crap"); - } - return host; + struct in_addr addr; + + addr.s_addr = str_to_addr(address); + return gethostbyaddr((char *) &addr, 4, AF_INET); /* IPv4 only for now */ } -/* */ -static struct hostent * -lookup_by_addr(const char *addr) +/* print the results as nslookup would */ +static struct hostent *hostent_fprint(struct hostent *host) { - struct hostent *host; - - host = gethostbyaddr(addr, 4, AF_INET); /* IPv4 only for now */ - if (host) { - fprintf(stdout, "Name: %s\n", host->h_name); - addr_list_fprint(host->h_addr_list, stdout); - } else { - herror("crap"); - } - return host; + if (host) { + printf("Name: %s\n", host->h_name); + addr_list_fprint(host->h_addr_list); + } else { + printf("*** Unknown host\n"); + } + return host; } -/* */ -static int -is_ip_address(const char *s) + +/* naive function to check whether char *s is an ip address */ +static int is_ip_address(const char *s) { - while (*s) { - if ((isdigit(*s)) || (*s == '.')) { s++; continue; } - return 0; - } - return 1; + while (*s) { + if ((isdigit(*s)) || (*s == '.')) { + s++; + continue; + } + return 0; + } + return 1; } /* ________________________________________________________________________ */ -int -nslookup_main(int argc, char **argv) +int nslookup_main(int argc, char **argv) { - struct in_addr addr; - - server_fprint(stdout); - if (is_ip_address(argv[1])) { - addr.s_addr = str_to_addr(argv[1]); - lookup_by_addr((char *) &addr); - } else { - lookup_by_name(argv[1]); - } - return 0; + struct hostent *host; + + if (argc < 2 || *argv[1]=='-') { + show_usage(); + } + + server_print(); + if (is_ip_address(argv[1])) { + host = gethostbyaddr_wrapper(argv[1]); + } else { + host = gethostbyname(argv[1]); + } + hostent_fprint(host); + return EXIT_SUCCESS; } -/* $Id: nslookup.c,v 1.1 2000/01/29 12:59:01 beppu Exp $ */ +/* $Id: nslookup.c,v 1.22 2001/02/20 06:14:08 andersen Exp $ */