int __dns_doqueries(unsigned char *dest, const char *name, int *rr, int rrcnt)
{
time_t t0 = time(0);
int fd;
FILE *f, _f;
unsigned char _buf[256];
char line[64], *s, *z;
union {
struct sockaddr_in sin;
struct sockaddr_in6 sin6;
} sa = {0}, ns[3] = {{0}};
socklen_t sl = sizeof sa.sin;
int nns = 0;
int family = AF_INET;
unsigned char q[280] = "", *r = dest;
int ql;
int rlen;
int got = 0, failed = 0;
int errcode = EAI_AGAIN;
int i, j;
struct timespec ts;
struct pollfd pfd;
int id;
int cs;
pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
/* Construct query template - RR and ID will be filled later */
if (strlen(name)-1 >= 254U) return EAI_NONAME;
q[2] = q[5] = 1;
strcpy((char *)q+13, name);
for (i=13; q[i]; i=j+1) {
for (j=i; q[j] && q[j] != '.'; j++);
if (j-i-1u > 62u) return EAI_NONAME;
q[i-1] = j-i;
}
q[i+3] = 1;
ql = i+4;
/* Make a reasonably unpredictable id */
clock_gettime(CLOCK_REALTIME, &ts);
id = ts.tv_nsec + ts.tv_nsec/65536UL & 0xffff;
/* Get nameservers from resolv.conf, fallback to localhost */
f = __fopen_rb_ca("/etc/resolv.conf", &_f, _buf, sizeof _buf);
if (f) for (nns=0; nns<3 && fgets(line, sizeof line, f); ) {
if (strncmp(line, "nameserver", 10) || !isspace(line[10]))
continue;
for (s=line+11; isspace(*s); s++);
for (z=s; *z && !isspace(*z); z++);
*z=0;
if (__ipparse(ns+nns, AF_UNSPEC, s) < 0) continue;
ns[nns].sin.sin_port = htons(53);
if (ns[nns++].sin.sin_family == AF_INET6) {
family = AF_INET6;
sl = sizeof sa.sin6;
}
}
if (f) __fclose_ca(f);
if (!nns) {
ns[0].sin.sin_family = family = AF_INET;
ns[0].sin.sin_port = htons(53);
ns[0].sin.sin_addr.s_addr = htonl(0x7f000001);
nns=1;
sl = sizeof sa.sin;
}
/* Get local address and open/bind a socket */
sa.sin.sin_family = family;
fd = socket(family, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
/* Handle case where system lacks IPv6 support */
if (fd < 0 && errno == EAFNOSUPPORT) {
if (family != AF_INET6) return EAI_SYSTEM;
fd = socket(AF_INET, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
family = AF_INET;
}
if (fd < 0) return EAI_SYSTEM;
/* Convert any IPv4 addresses in a mixed environment to v4-mapped */
if (family == AF_INET6) {
setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, &(int){0}, sizeof 0);
int getaddrinfo(const char *host, const char *serv, const struct addrinfo *hint, struct addrinfo **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 && port > 65535) return EAI_SERVICE;
if (!port) {
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;
}
port = htons(port);
}
if (!host) {
if (family == AF_UNSPEC) family = AF_INET;
buf = calloc(sizeof *buf, 1+EXTRA);
if (!buf) return EAI_MEMORY;
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.sin.sin_family = family;
buf->sa.sin.sin_port = port;
if (!(flags & AI_PASSIVE)) {
if (family == AF_INET) {
0[(uint8_t*)&buf->sa.sin.sin_addr.s_addr]=127;
3[(uint8_t*)&buf->sa.sin.sin_addr.s_addr]=1;
} else buf[0].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;
}
