diff options
| -rw-r--r-- | networking/nslookup.c | 205 | ||||
| -rw-r--r-- | networking/ping6.c | 2 |
2 files changed, 81 insertions, 126 deletions
diff --git a/networking/nslookup.c b/networking/nslookup.c index 54e71c4..dd49e26 100644 --- a/networking/nslookup.c +++ b/networking/nslookup.c @@ -11,152 +11,116 @@ * Licensed under GPLv2 or later, see file LICENSE in this tarball for details. */ -#include <ctype.h> -#include <errno.h> -#include <stdio.h> -#include <string.h> -#include <stdlib.h> - -#include <stdint.h> -#include <netdb.h> -#include <sys/socket.h> -#include <sys/types.h> -#include <netinet/in.h> #include <resolv.h> -#include <arpa/inet.h> #include "busybox.h" /* - | I'm only implementing non-interactive mode; - | I totally forgot nslookup even had an interactive mode. + * I'm only implementing non-interactive mode; + * I totally forgot nslookup even had an interactive mode. */ -/* only works for IPv4 */ -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); - printf("%d.%d.%d.%d", split[0], split[1], split[2], split[3]); - return 0; -} - -/* takes the NULL-terminated array h_addr_list, and - * prints its contents appropriately +/* Examples of 'standard' nslookup output + * $ nslookup yahoo.com + * Server: 128.193.0.10 + * Address: 128.193.0.10#53 + * + * Non-authoritative answer: + * Name: yahoo.com + * Address: 216.109.112.135 + * Name: yahoo.com + * Address: 66.94.234.13 + * + * $ nslookup 204.152.191.37 + * Server: 128.193.4.20 + * Address: 128.193.4.20#53 + * + * Non-authoritative answer: + * 37.191.152.204.in-addr.arpa canonical name = 37.32-27.191.152.204.in-addr.arpa. + * 37.32-27.191.152.204.in-addr.arpa name = zeus-pub2.kernel.org. + * + * Authoritative answers can be found from: + * 32-27.191.152.204.in-addr.arpa nameserver = ns1.kernel.org. + * 32-27.191.152.204.in-addr.arpa nameserver = ns2.kernel.org. + * 32-27.191.152.204.in-addr.arpa nameserver = ns3.kernel.org. + * ns1.kernel.org internet address = 140.211.167.34 + * ns2.kernel.org internet address = 204.152.191.4 + * ns3.kernel.org internet address = 204.152.191.36 */ -static int addr_list_fprint(char **h_addr_list) -{ - 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(", "); - } - } +static int sockaddr_to_dotted(struct sockaddr *saddr, char *buf, int buflen) +{ + if (buflen <= 0) return -1; + buf[0] = '\0'; + if (saddr->sa_family == AF_INET) { + inet_ntop(AF_INET, &((struct sockaddr_in*)saddr)->sin_addr, buf, buflen); + return 0; } - puts(""); - return 0; + if (saddr->sa_family == AF_INET6) { + inet_ntop(AF_INET6, &((struct sockaddr_in6*)saddr)->sin6_addr, buf, buflen); + return 0; + } + return -1; } -/* print the results as nslookup would */ -static struct hostent *hostent_fprint(struct hostent *host, const char *server_host) +static int print_host(const char *hostname, const char *header) { - if (host) { - printf("%s %s\n", server_host, host->h_name); - addr_list_fprint(host->h_addr_list); + char str[128]; /* IPv6 address will fit, hostnames hopefully too */ + struct addrinfo *result = NULL; + int rc; + struct addrinfo hint; + + memset(&hint, 0 , sizeof(hint)); + /* hint.ai_family = AF_UNSPEC; - zero anyway */ + /* Needed. Or else we will get each address thrice (or more) + * for each possible socket type (tcp,udp,raw...): */ + hint.ai_socktype = SOCK_STREAM; + // hint.ai_flags = AI_CANONNAME; + rc = getaddrinfo(hostname, NULL /*service*/, &hint, &result); + if (!rc) { + struct addrinfo *cur = result; + // printf("%s\n", cur->ai_canonname); ? + while (cur) { + sockaddr_to_dotted(cur->ai_addr, str, sizeof(str)); + printf("%s %s\nAddress: %s", header, hostname, str); + if (getnameinfo(cur->ai_addr, cur->ai_addrlen, str, sizeof(str), NULL, 0, NI_NAMEREQD)) + str[0] = '\0'; + printf(" %s\n", str); + cur = cur->ai_next; + } } else { - printf("*** Unknown host\n"); + bb_error_msg("getaddrinfo('%s') failed: %s", hostname, gai_strerror(rc)); } - return host; -} - -/* changes a c-string matching the perl regex \d+\.\d+\.\d+\.\d+ - * into a uint32_t - */ -static uint32_t str_to_addr(const char *addr) -{ - uint32_t split[4]; - uint32_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 */ + freeaddrinfo(result); + return (rc != 0); } -/* 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), "Server:"); - puts(""); -} /* alter the global _res nameserver structure to use an explicit dns server instead of what is in /etc/resolv.h */ -static inline void set_default_dns(char *server) +static void set_default_dns(char *server) { struct in_addr server_in_addr; - if(inet_aton(server,&server_in_addr)) - { + if (inet_pton(AF_INET, server, &server_in_addr) > 0) { _res.nscount = 1; _res.nsaddr_list[0].sin_addr = server_in_addr; } } -/* naive function to check whether char *s is an ip address */ -static int is_ip_address(const char *s) + +/* lookup the default nameserver and display it */ +static void server_print(void) { - while (*s) { - if ((isdigit(*s)) || (*s == '.')) { - s++; - continue; - } - return 0; - } - return 1; + char str[INET6_ADDRSTRLEN]; + + sockaddr_to_dotted((struct sockaddr*)&_res.nsaddr_list[0], str, sizeof(str)); + print_host(str, "Server:"); + puts(""); } -/* ________________________________________________________________________ */ + int nslookup_main(int argc, char **argv) { - struct hostent *host; - /* * initialize DNS structure _res used in printing the default * name server and in the explicit name server option feature. @@ -172,22 +136,13 @@ int nslookup_main(int argc, char **argv) * standard nslookup */ - if (argc < 2 || *argv[1]=='-' || argc > 3) + if (argc < 2 || *argv[1] == '-' || argc > 3) bb_show_usage(); else if(argc == 3) set_default_dns(argv[2]); server_print(); - if (is_ip_address(argv[1])) { - host = gethostbyaddr_wrapper(argv[1]); - } else { - host = xgethostbyname(argv[1]); - } - hostent_fprint(host, "Name: "); - if (host) { - return EXIT_SUCCESS; - } - return EXIT_FAILURE; + return print_host(argv[1], "Name: "); } /* $Id: nslookup.c,v 1.33 2004/10/13 07:25:01 andersen Exp $ */ diff --git a/networking/ping6.c b/networking/ping6.c index a064f2f..af9c00e 100644 --- a/networking/ping6.c +++ b/networking/ping6.c @@ -329,7 +329,7 @@ static void ping(const char *host) pingaddr.sin6_family = AF_INET6; hostent = xgethostbyname2(host, AF_INET6); if (hostent->h_addrtype != AF_INET6) - bb_error_msg_and_die("unknown address type; only AF_INET6 is currently supported."); + bb_error_msg_and_die("unknown address type; only AF_INET6 is currently supported"); memcpy(&pingaddr.sin6_addr, hostent->h_addr, sizeof(pingaddr.sin6_addr)); |