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#include <stdlib.h>
#include <stdio.h>
#include <netdb.h>
#include <netinet/in.h>
#include <sys/socket.h>
#include <unistd.h>
#include <string.h>
#include <ctype.h>
#include "__dns.h"
#include "stdio_impl.h"
static int is_valid(const char *host)
{
const unsigned char *s;
if (strlen(host)-1 > 254 || mbstowcs(0, host, 0) > 255) return 0;
for (s=(void *)host; *s>=0x80 || *s=='.' || *s=='-' || isalnum(*s); s++);
return !*s;
}
#if 0
static int have_af(int family)
{
struct sockaddr_in6 sin6 = { .sin6_family = family };
socklen_t sl = family == AF_INET
? sizeof(struct sockaddr_in)
: sizeof(struct sockaddr_in6);
int sock = socket(family, SOCK_STREAM, 0);
int have = !bind(sock, (void *)&sin6, sl);
close(sock);
return have;
}
#endif
#include <stdlib.h>
#include <netdb.h>
union sa {
struct sockaddr_in sin;
struct sockaddr_in6 sin6;
};
struct aibuf {
struct addrinfo ai;
union sa sa;
};
/* Extra slots needed for storing canonical name */
#define EXTRA ((256+sizeof(struct aibuf)-1)/sizeof(struct aibuf))
int getaddrinfo(const char *restrict host, const char *restrict serv, const struct addrinfo *restrict hint, struct addrinfo **restrict res)
{
int flags = hint ? hint->ai_flags : 0;
int family = hint ? hint->ai_family : AF_UNSPEC;
int type = hint ? hint->ai_socktype : 0;
int proto = hint ? hint->ai_protocol : 0;
unsigned long port = 0;
struct aibuf *buf;
union sa sa = {{0}};
unsigned char reply[1024];
int i, j;
char line[512];
FILE *f, _f;
unsigned char _buf[1024];
char *z;
int result;
int cnt;
if (host && strlen(host)>255) return EAI_NONAME;
if (serv && strlen(serv)>32) return EAI_SERVICE;
if (type && !proto)
proto = type==SOCK_DGRAM ? IPPROTO_UDP : IPPROTO_TCP;
if (!type && proto)
type = proto==IPPROTO_UDP ? SOCK_DGRAM : SOCK_STREAM;
if (serv) {
if (!*serv) return EAI_SERVICE;
port = strtoul(serv, &z, 10);
if (*z) {
size_t servlen = strlen(serv);
char *end = line;
if (flags & AI_NUMERICSERV) return EAI_SERVICE;
f = __fopen_rb_ca("/etc/services", &_f, _buf, sizeof _buf);
if (!f) return EAI_SERVICE;
while (fgets(line, sizeof line, f)) {
if (strncmp(line, serv, servlen) || !isspace(line[servlen]))
continue;
port = strtoul(line+servlen, &end, 10);
if (strncmp(end, proto==IPPROTO_UDP ? "/udp" : "/tcp", 4))
continue;
break;
}
__fclose_ca(f);
if (feof(f)) return EAI_SERVICE;
}
if (port > 65535) return EAI_SERVICE;
port = htons(port);
}
if (!host) {
if (family == AF_UNSPEC) {
cnt = 2; family = AF_INET;
} else {
cnt = 1;
}
buf = calloc(sizeof *buf, cnt);
if (!buf) return EAI_MEMORY;
for (i=0; i<cnt; i++) {
if (i) family = AF_INET6;
buf[i].ai.ai_protocol = proto;
buf[i].ai.ai_socktype = type;
buf[i].ai.ai_addr = (void *)&buf[i].sa;
buf[i].ai.ai_addrlen = family==AF_INET6
? sizeof sa.sin6 : sizeof sa.sin;
buf[i].ai.ai_family = family;
buf[i].sa.sin.sin_family = family;
buf[i].sa.sin.sin_port = port;
if (i+1<cnt) buf[i].ai.ai_next = &buf[i+1].ai;
if (!(flags & AI_PASSIVE)) {
if (family == AF_INET) {
0[(uint8_t*)&buf[i].sa.sin.sin_addr.s_addr]=127;
3[(uint8_t*)&buf[i].sa.sin.sin_addr.s_addr]=1;
} else buf[i].sa.sin6.sin6_addr.s6_addr[15] = 1;
}
}
*res = &buf->ai;
return 0;
}
if (!*host) return EAI_NONAME;
/* Try as a numeric address */
if (__ipparse(&sa, family, host) >= 0) {
buf = calloc(sizeof *buf, 1+EXTRA);
if (!buf) return EAI_MEMORY;
family = sa.sin.sin_family;
buf->ai.ai_protocol = proto;
buf->ai.ai_socktype = type;
buf->ai.ai_addr = (void *)&buf->sa;
buf->ai.ai_addrlen = family==AF_INET6 ? sizeof sa.sin6 : sizeof sa.sin;
buf->ai.ai_family = family;
buf->ai.ai_canonname = (char *)host;
buf->sa = sa;
buf->sa.sin.sin_port = port;
*res = &buf->ai;
return 0;
}
if (flags & AI_NUMERICHOST) return EAI_NONAME;
f = __fopen_rb_ca("/etc/hosts", &_f, _buf, sizeof _buf);
if (f) while (fgets(line, sizeof line, f)) {
char *p;
size_t l = strlen(host);
if ((p=strchr(line, '#'))) *p++='\n', *p=0;
for(p=line+1; (p=strstr(p, host)) &&
(!isspace(p[-1]) || !isspace(p[l])); p++);
if (!p) continue;
__fclose_ca(f);
/* Isolate IP address to parse */
for (p=line; *p && !isspace(*p); p++);
*p++ = 0;
if (__ipparse(&sa, family, line) < 0) return EAI_NONAME;
/* Allocate and fill result buffer */
buf = calloc(sizeof *buf, 1+EXTRA);
if (!buf) return EAI_MEMORY;
family = sa.sin.sin_family;
buf->ai.ai_protocol = proto;
buf->ai.ai_socktype = type;
buf->ai.ai_addr = (void *)&buf->sa;
buf->ai.ai_addrlen = family==AF_INET6 ? sizeof sa.sin6 : sizeof sa.sin;
buf->ai.ai_family = family;
buf->sa = sa;
buf->sa.sin.sin_port = port;
/* Extract first name as canonical name */
for (; *p && isspace(*p); p++);
buf->ai.ai_canonname = (void *)(buf+1);
snprintf(buf->ai.ai_canonname, 256, "%s", p);
for (p=buf->ai.ai_canonname; *p && !isspace(*p); p++);
*p = 0;
if (!is_valid(buf->ai.ai_canonname))
buf->ai.ai_canonname = 0;
*res = &buf->ai;
return 0;
}
if (f) __fclose_ca(f);
#if 0
f = __fopen_rb_ca("/etc/resolv.conf", &_f, _buf, sizeof _buf);
if (f) while (fgets(line, sizeof line, f)) {
if (!isspace(line[10]) || (strncmp(line, "search", 6)
&& strncmp(line, "domain", 6))) continue;
}
if (f) __fclose_ca(f);
#endif
/* Perform one or more DNS queries for host */
memset(reply, 0, sizeof reply);
result = __dns_query(reply, host, family, 0);
if (result < 0) return result;
cnt = __dns_count_addrs(reply, result);
if (cnt <= 0) return EAI_NONAME;
buf = calloc(sizeof *buf, cnt+EXTRA);
if (!buf) return EAI_MEMORY;
i = 0;
if (family != AF_INET6) {
j = __dns_get_rr(&buf[i].sa.sin.sin_addr, sizeof *buf, 4, cnt-i, reply, RR_A, 0);
while (j--) buf[i++].sa.sin.sin_family = AF_INET;
}
if (family != AF_INET) {
j = __dns_get_rr(&buf[i].sa.sin6.sin6_addr, sizeof *buf, 16, cnt-i, reply, RR_AAAA, 0);
while (j--) buf[i++].sa.sin.sin_family = AF_INET6;
}
if (result>1) {
j = __dns_get_rr(&buf[i].sa.sin.sin_addr, sizeof *buf, 4, cnt-i, reply+512, RR_A, 0);
while (j--) buf[i++].sa.sin.sin_family = AF_INET;
j = __dns_get_rr(&buf[i].sa.sin6.sin6_addr, sizeof *buf, 16, cnt-i, reply+512, RR_AAAA, 0);
while (j--) buf[i++].sa.sin.sin_family = AF_INET6;
}
if (__dns_get_rr((void *)&buf[cnt], 0, 256, 1, reply, RR_CNAME, 1) <= 0)
strcpy((void *)&buf[cnt], host);
for (i=0; i<cnt; i++) {
buf[i].ai.ai_protocol = proto;
buf[i].ai.ai_socktype = type;
buf[i].ai.ai_addr = (void *)&buf[i].sa;
buf[i].ai.ai_addrlen = buf[i].sa.sin.sin_family==AF_INET6
? sizeof sa.sin6 : sizeof sa.sin;
buf[i].ai.ai_family = buf[i].sa.sin.sin_family;
buf[i].sa.sin.sin_port = port;
buf[i].ai.ai_next = &buf[i+1].ai;
buf[i].ai.ai_canonname = (void *)&buf[cnt];
}
buf[cnt-1].ai.ai_next = 0;
*res = &buf->ai;
return 0;
}
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