+#include <sys/socket.h>
remove unused 'int i' form main whitespacing only
This commit is contained in:
"Vladimir N. Oleynik"
@@ -19,6 +19,7 @@
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#include <string.h>
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#include <signal.h>
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#include <arpa/inet.h>
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#include <sys/socket.h>
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#include <ctype.h>
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#include "libbb.h"
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@@ -45,28 +46,28 @@ static const int MAX_PACK_LEN = 512 + 1;
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static const int REQ_A = 1;
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static const int REQ_PTR = 12;
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struct dns_repl { // resource record, add 0 or 1 to accepted dns_msg in resp
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uint16_t rlen;
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uint8_t *r; // resource
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uint16_t flags;
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struct dns_repl { // resource record, add 0 or 1 to accepted dns_msg in resp
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uint16_t rlen;
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uint8_t *r; // resource
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uint16_t flags;
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};
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struct dns_head { // the message from client and first part of response mag
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uint16_t id;
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uint16_t flags;
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uint16_t nquer; // accepts 0
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uint16_t nansw; // 1 in response
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uint16_t nauth; // 0
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uint16_t nadd; // 0
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struct dns_head { // the message from client and first part of response mag
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uint16_t id;
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uint16_t flags;
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uint16_t nquer; // accepts 0
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uint16_t nansw; // 1 in response
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uint16_t nauth; // 0
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uint16_t nadd; // 0
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};
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struct dns_prop {
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uint16_t type;
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uint16_t class;
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uint16_t type;
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uint16_t class;
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};
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struct dns_entry { // element of known name, ip address and reversed ip address
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struct dns_entry *next;
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char ip[IP_STRING_LEN]; // dotted decimal IP
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char rip[IP_STRING_LEN]; // length decimal reversed IP
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struct dns_entry { // element of known name, ip address and reversed ip address
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struct dns_entry *next;
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char ip[IP_STRING_LEN]; // dotted decimal IP
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char rip[IP_STRING_LEN]; // length decimal reversed IP
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char name[MAX_HOST_LEN];
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};
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@@ -80,10 +81,10 @@ static uint32_t ttl = DEFAULT_TTL;
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static void
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convname(char *a, uint8_t *q)
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{
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int i = (q[0] == '.')?0:1;
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int i = (q[0] == '.') ? 0 : 1;
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for(; i < MAX_HOST_LEN-1 && *q; i++, q++)
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a[i] = tolower(*q);
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a[0] = i - 1;
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a[0] = i - 1;
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a[i] = 0;
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}
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@@ -93,7 +94,7 @@ convname(char *a, uint8_t *q)
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static void
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undot(uint8_t * rip)
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{
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int i=0, s=0;
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int i = 0, s = 0;
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while(rip[i]) i++;
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for(--i; i >= 0; i--) {
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if(rip[i] == '.') {
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@@ -109,14 +110,14 @@ undot(uint8_t * rip)
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static void
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log_message(char *filename, char *message)
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{
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FILE *logfile;
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if (!daemonmode)
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return;
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logfile = fopen(filename, "a");
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if (!logfile)
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return;
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fprintf(logfile, "%s\n", message);
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fclose(logfile);
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FILE *logfile;
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if (!daemonmode)
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return;
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logfile = fopen(filename, "a");
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if (!logfile)
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return;
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fprintf(logfile, "%s\n", message);
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fclose(logfile);
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}
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/*
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@@ -132,7 +133,7 @@ static int
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getfileentry(FILE * fp, struct dns_entry *s, int verb)
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{
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unsigned int a,b,c,d;
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char *r, *name;
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char *r, *name;
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restart:
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if(!(r = bb_get_line_from_file(fp)))
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@@ -166,28 +167,28 @@ restart:
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static void
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dnsentryinit(int verb)
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{
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FILE *fp;
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struct dns_entry *m, *prev;
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prev = dnsentry = NULL;
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FILE *fp;
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struct dns_entry *m, *prev;
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prev = dnsentry = NULL;
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if(!(fp = fopen(fileconf, "r")))
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if(!(fp = fopen(fileconf, "r")))
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bb_perror_msg_and_die("open %s",fileconf);
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while (1) {
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if(!(m = (struct dns_entry *)malloc(sizeof(struct dns_entry))))
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while (1) {
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if(!(m = (struct dns_entry *)malloc(sizeof(struct dns_entry))))
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bb_perror_msg_and_die("malloc dns_entry");
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m->next = NULL;
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if (getfileentry(fp, m, verb))
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break;
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m->next = NULL;
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if (getfileentry(fp, m, verb))
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break;
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if (prev == NULL)
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dnsentry = m;
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else
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prev->next = m;
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prev = m;
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}
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fclose(fp);
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if (prev == NULL)
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dnsentry = m;
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else
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prev->next = m;
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prev = m;
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}
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fclose(fp);
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}
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@@ -197,28 +198,28 @@ dnsentryinit(int verb)
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static int
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listen_socket(char *iface_addr, int listen_port)
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{
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struct sockaddr_in a;
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char msg[100];
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int s;
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int yes = 1;
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if ((s = socket(PF_INET, SOCK_DGRAM, 0)) < 0)
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bb_perror_msg_and_die("socket() failed");
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struct sockaddr_in a;
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char msg[100];
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int s;
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int yes = 1;
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if ((s = socket(PF_INET, SOCK_DGRAM, 0)) < 0)
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bb_perror_msg_and_die("socket() failed");
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#ifdef SO_REUSEADDR
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if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (char *)&yes, sizeof(yes)) < 0)
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bb_perror_msg_and_die("setsockopt() failed");
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if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (char *)&yes, sizeof(yes)) < 0)
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bb_perror_msg_and_die("setsockopt() failed");
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#endif
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memset(&a, 0, sizeof(a));
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a.sin_port = htons(listen_port);
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a.sin_family = AF_INET;
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if (!inet_aton(iface_addr, &a.sin_addr))
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bb_perror_msg_and_die("bad iface address");
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if (bind(s, (struct sockaddr *)&a, sizeof(a)) < 0)
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bb_perror_msg_and_die("bind() failed");
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listen(s, 50);
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sprintf(msg, "accepting UDP packets on addr:port %s:%d\n",
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iface_addr, (int)listen_port);
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log_message(LOG_FILE, msg);
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return s;
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memset(&a, 0, sizeof(a));
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a.sin_port = htons(listen_port);
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a.sin_family = AF_INET;
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if (!inet_aton(iface_addr, &a.sin_addr))
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bb_perror_msg_and_die("bad iface address");
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if (bind(s, (struct sockaddr *)&a, sizeof(a)) < 0)
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bb_perror_msg_and_die("bind() failed");
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listen(s, 50);
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sprintf(msg, "accepting UDP packets on addr:port %s:%d\n",
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iface_addr, (int)listen_port);
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log_message(LOG_FILE, msg);
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return s;
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}
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/*
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@@ -229,16 +230,16 @@ static int
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table_lookup(uint16_t type, uint8_t * as, uint8_t * qs)
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{
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int i;
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struct dns_entry *d=dnsentry;
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struct dns_entry *d=dnsentry;
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do {
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do {
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#ifdef DEBUG
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char *p,*q;
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char *p,*q;
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q = (char *)&(qs[1]);
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p = &(d->name[1]);
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fprintf(stderr, "\ntest: %d <%s> <%s> %d", strlen(p), p, q, strlen(q));
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fprintf(stderr, "\ntest: %d <%s> <%s> %d", strlen(p), p, q, strlen(q));
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#endif
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if (type == REQ_A) { /* search by host name */
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if (type == REQ_A) { /* search by host name */
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for(i = 1; i <= (int)(d->name[0]); i++)
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if(tolower(qs[i]) != d->name[i])
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continue;
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@@ -251,114 +252,114 @@ table_lookup(uint16_t type, uint8_t * as, uint8_t * qs)
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#endif
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return 0;
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}
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else if (type == REQ_PTR) { /* search by IP-address */
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else if (type == REQ_PTR) { /* search by IP-address */
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if (!strncmp((char*)&d->rip[1], (char*)&qs[1], strlen(d->rip)-1)) {
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strcpy((char *)as, d->name);
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return 0;
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}
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}
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} while ((d = d->next) != NULL);
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return -1;
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strcpy((char *)as, d->name);
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return 0;
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}
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}
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} while ((d = d->next) != NULL);
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return -1;
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}
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/*
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* Decode message and generate answer
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*/
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#define eret(s) do { fprintf (stderr, "%s\n", s); return -1; } while (0)
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#define eret(s) do { fprintf (stderr, "%s\n", s); return -1; } while (0)
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static int
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process_packet(uint8_t * buf)
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{
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struct dns_head *head;
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struct dns_prop *qprop;
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struct dns_repl outr;
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void *next, *from, *answb;
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struct dns_head *head;
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struct dns_prop *qprop;
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struct dns_repl outr;
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void *next, *from, *answb;
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uint8_t answstr[MAX_NAME_LEN + 1];
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int lookup_result, type, len, packet_len;
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uint16_t flags;
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uint8_t answstr[MAX_NAME_LEN + 1];
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int lookup_result, type, len, packet_len;
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uint16_t flags;
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answstr[0] = '\0';
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answstr[0] = '\0';
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head = (struct dns_head *)buf;
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if (head->nquer == 0)
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eret("no queries");
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head = (struct dns_head *)buf;
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if (head->nquer == 0)
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eret("no queries");
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if ((head->flags & 0x8000))
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eret("ignoring response packet");
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if ((head->flags & 0x8000))
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eret("ignoring response packet");
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from = (void *)&head[1]; // start of query string
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next = answb = from + strlen((char *)&head[1]) + 1 + sizeof(struct dns_prop); // where to append answer block
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from = (void *)&head[1]; // start of query string
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next = answb = from + strlen((char *)&head[1]) + 1 + sizeof(struct dns_prop); // where to append answer block
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outr.rlen = 0; // may change later
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outr.r = NULL;
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outr.flags = 0;
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outr.rlen = 0; // may change later
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outr.r = NULL;
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outr.flags = 0;
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qprop = (struct dns_prop *)(answb - 4);
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type = ntohs(qprop->type);
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qprop = (struct dns_prop *)(answb - 4);
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type = ntohs(qprop->type);
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// only let REQ_A and REQ_PTR pass
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if (!(type == REQ_A || type == REQ_PTR)) {
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goto empty_packet; /* we can't handle the query type */
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}
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// only let REQ_A and REQ_PTR pass
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if (!(type == REQ_A || type == REQ_PTR)) {
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goto empty_packet; /* we can't handle the query type */
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}
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if (ntohs(qprop->class) != 1 /* class INET */ ) {
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outr.flags = 4; /* not supported */
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goto empty_packet;
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}
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/* we only support standard queries */
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if (ntohs(qprop->class) != 1 /* class INET */ ) {
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outr.flags = 4; /* not supported */
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goto empty_packet;
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}
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/* we only support standard queries */
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if ((ntohs(head->flags) & 0x7800) != 0)
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goto empty_packet;
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if ((ntohs(head->flags) & 0x7800) != 0)
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goto empty_packet;
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// We have a standard query
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// We have a standard query
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log_message(LOG_FILE, (char *)head);
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lookup_result = table_lookup(type, answstr, (uint8_t*)(&head[1]));
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if (lookup_result != 0) {
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outr.flags = 3 | 0x0400; //name do not exist and auth
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goto empty_packet;
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}
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if (type == REQ_A) { // return an address
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struct in_addr a;
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if (!inet_aton((char*)answstr, &a)) {//dotted dec to long conv
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outr.flags = 1; /* Frmt err */
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goto empty_packet;
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}
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memcpy(answstr, &a.s_addr, 4); // save before a disappears
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outr.rlen = 4; // uint32_t IP
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}
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else
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outr.rlen = strlen((char *)answstr) + 1; // a host name
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outr.r = answstr; // 32 bit ip or a host name
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outr.flags |= 0x0400; /* authority-bit */
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// we have an answer
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head->nansw = htons(1);
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log_message(LOG_FILE, (char *)head);
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lookup_result = table_lookup(type, answstr, (uint8_t*)(&head[1]));
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if (lookup_result != 0) {
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outr.flags = 3 | 0x0400; //name do not exist and auth
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goto empty_packet;
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}
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if (type == REQ_A) { // return an address
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struct in_addr a;
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if (!inet_aton((char*)answstr, &a)) {//dotted dec to long conv
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outr.flags = 1; /* Frmt err */
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goto empty_packet;
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}
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memcpy(answstr, &a.s_addr, 4); // save before a disappears
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outr.rlen = 4; // uint32_t IP
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}
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else
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outr.rlen = strlen((char *)answstr) + 1; // a host name
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outr.r = answstr; // 32 bit ip or a host name
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outr.flags |= 0x0400; /* authority-bit */
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// we have an answer
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head->nansw = htons(1);
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// copy query block to answer block
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len = answb - from;
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memcpy(answb, from, len);
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next += len;
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// copy query block to answer block
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len = answb - from;
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memcpy(answb, from, len);
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next += len;
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// and append answer rr
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*(uint32_t *) next = htonl(ttl);
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next += 4;
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*(uint16_t *) next = htons(outr.rlen);
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next += 2;
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memcpy(next, (void *)answstr, outr.rlen);
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next += outr.rlen;
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// and append answer rr
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*(uint32_t *) next = htonl(ttl);
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next += 4;
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*(uint16_t *) next = htons(outr.rlen);
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next += 2;
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memcpy(next, (void *)answstr, outr.rlen);
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next += outr.rlen;
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empty_packet:
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flags = ntohs(head->flags);
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// clear rcode and RA, set responsebit and our new flags
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flags |= (outr.flags & 0xff80) | 0x8000;
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head->flags = htons(flags);
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head->nauth = head->nadd = htons(0);
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head->nquer = htons(1);
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flags = ntohs(head->flags);
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// clear rcode and RA, set responsebit and our new flags
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flags |= (outr.flags & 0xff80) | 0x8000;
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head->flags = htons(flags);
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head->nauth = head->nadd = htons(0);
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head->nquer = htons(1);
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|
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packet_len = next - (void *)buf;
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return packet_len;
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packet_len = next - (void *)buf;
|
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return packet_len;
|
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}
|
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|
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/*
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@@ -367,9 +368,9 @@ process_packet(uint8_t * buf)
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static void
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interrupt(int x)
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{
|
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unlink(LOCK_FILE);
|
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write(2, "interrupt exiting\n", 18);
|
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exit(2);
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unlink(LOCK_FILE);
|
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write(2, "interrupt exiting\n", 18);
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exit(2);
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}
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|
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#define is_daemon() (flags&16)
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@@ -378,14 +379,14 @@ interrupt(int x)
|
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|
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int dnsd_main(int argc, char **argv)
|
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{
|
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int i, udps;
|
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uint16_t port = 53;
|
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uint8_t buf[MAX_PACK_LEN];
|
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int udps;
|
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uint16_t port = 53;
|
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uint8_t buf[MAX_PACK_LEN];
|
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unsigned long flags = 0;
|
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char *listen_interface = "0.0.0.0";
|
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char *listen_interface = "0.0.0.0";
|
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char *sttl=NULL, *sport=NULL;
|
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|
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if(argc > 1)
|
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if(argc > 1)
|
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flags = bb_getopt_ulflags(argc, argv, "i:c:t:p:dv", &listen_interface, &fileconf, &sttl, &sport);
|
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if(sttl)
|
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if(!(ttl = atol(sttl)))
|
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@@ -410,59 +411,59 @@ int dnsd_main(int argc, char **argv)
|
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}
|
||||
#endif /* uClinuvx */
|
||||
|
||||
dnsentryinit(is_verbose());
|
||||
dnsentryinit(is_verbose());
|
||||
|
||||
signal(SIGINT, interrupt);
|
||||
signal(SIGPIPE, SIG_IGN);
|
||||
signal(SIGHUP, SIG_IGN);
|
||||
signal(SIGINT, interrupt);
|
||||
signal(SIGPIPE, SIG_IGN);
|
||||
signal(SIGHUP, SIG_IGN);
|
||||
#ifdef SIGTSTP
|
||||
signal(SIGTSTP, SIG_IGN);
|
||||
signal(SIGTSTP, SIG_IGN);
|
||||
#endif
|
||||
#ifdef SIGURG
|
||||
signal(SIGURG, SIG_IGN);
|
||||
signal(SIGURG, SIG_IGN);
|
||||
#endif
|
||||
|
||||
udps = listen_socket(listen_interface, port);
|
||||
if (udps < 0)
|
||||
exit(1);
|
||||
udps = listen_socket(listen_interface, port);
|
||||
if (udps < 0)
|
||||
exit(1);
|
||||
|
||||
while (1) {
|
||||
fd_set fdset;
|
||||
int r;
|
||||
while (1) {
|
||||
fd_set fdset;
|
||||
int r;
|
||||
|
||||
FD_ZERO(&fdset);
|
||||
FD_SET(udps, &fdset);
|
||||
// Block until a message arrives
|
||||
if((r = select(udps + 1, &fdset, NULL, NULL, NULL)) < 0)
|
||||
FD_ZERO(&fdset);
|
||||
FD_SET(udps, &fdset);
|
||||
// Block until a message arrives
|
||||
if((r = select(udps + 1, &fdset, NULL, NULL, NULL)) < 0)
|
||||
bb_perror_msg_and_die("select error");
|
||||
else
|
||||
if(r == 0)
|
||||
bb_perror_msg_and_die("select spurious return");
|
||||
bb_perror_msg_and_die("select spurious return");
|
||||
|
||||
/* Can this test ever be false? */
|
||||
if (FD_ISSET(udps, &fdset)) {
|
||||
struct sockaddr_in from;
|
||||
int fromlen = sizeof(from);
|
||||
r = recvfrom(udps, buf, sizeof(buf), 0,
|
||||
(struct sockaddr *)&from,
|
||||
(void *)&fromlen);
|
||||
/* Can this test ever be false? */
|
||||
if (FD_ISSET(udps, &fdset)) {
|
||||
struct sockaddr_in from;
|
||||
int fromlen = sizeof(from);
|
||||
r = recvfrom(udps, buf, sizeof(buf), 0,
|
||||
(struct sockaddr *)&from,
|
||||
(void *)&fromlen);
|
||||
if(is_verbose())
|
||||
fprintf(stderr, "\n--- Got UDP ");
|
||||
log_message(LOG_FILE, "\n--- Got UDP ");
|
||||
fprintf(stderr, "\n--- Got UDP ");
|
||||
log_message(LOG_FILE, "\n--- Got UDP ");
|
||||
|
||||
if (r < 12 || r > 512) {
|
||||
bb_error_msg("invalid packet size");
|
||||
continue;
|
||||
}
|
||||
if (r > 0) {
|
||||
r = process_packet(buf);
|
||||
if (r > 0)
|
||||
sendto(udps, buf,
|
||||
r, 0, (struct sockaddr *)&from,
|
||||
fromlen);
|
||||
}
|
||||
} // end if
|
||||
} // end while
|
||||
if (r < 12 || r > 512) {
|
||||
bb_error_msg("invalid packet size");
|
||||
continue;
|
||||
}
|
||||
if (r > 0) {
|
||||
r = process_packet(buf);
|
||||
if (r > 0)
|
||||
sendto(udps, buf,
|
||||
r, 0, (struct sockaddr *)&from,
|
||||
fromlen);
|
||||
}
|
||||
} // end if
|
||||
} // end while
|
||||
return 0;
|
||||
}
|
||||
|
||||
|
||||
Reference in New Issue
Block a user